-
Introduction: The green chemistry route (microwave) was used to produce nanocomposite materials based on activated carbon (AC) and manganese (Mn) oxide nanostructures. XRD analysis revealed that amorphous and crystalline oxide structures were synthesized. Scanning electron microscopy studies revealed rodlike a-MnO2 for the pristine sample, while cubic Mn3O4 and irregularly shaped MnO2 structures anchored on the AC substrate, with the nanostructures being uniformly distributed on the AC. The electrochemical tests of the composites as electrodes showed that the amorphous AC-MnO2 had a speci?c capacitance of 180 F g1, nearly four times higher than that of the crystalline AC-Mn3O4 composite electrode (55 F g1). The coulombic ef?ciency for the AC-MnO2 cell was 98% after 5000 cycles, indicating only a small loss of capacitance. The green route technique and good electrochemical properties indicate that the amorphous AC-MnO2 nanocomposite could be a good material for high-capacity, low-cost, and environmentally friendly electrodes for electrochemical capacitors.
Introduction: This study investigates how innovation affects business performance in small and medium-
sized enterprises (SMEs) in an up-and-coming market, like Nigeria. Data was collected from
200 respondents of six SMEs companies based in Nigeria. Innovation was measured using
the OECD Oslo scale (2005). The study demonstrated that there is a high correlation among
factors used to measure innovation. And secondly, innovation was found to influence
business performance.
Introduction: The study identified existing corporate entrepreneurship (CE) activities in the
telecommunication industry in Nigeria, examined it influence on the growth of the industry
and ascertained the effect of employee retention strategies on CE activities. It also assessed
the challenges confronting corporate entrepreneurship activities and employee retention
strategies in the industry.
Introduction: The concerns of human resource management in the organization, is to optimize
organizational performance through planned employees satisfaction. Thus achieving
organisation's objectives depends largely on employees' attitude and behaviours. In this
study, relations between selected human resource management practices and
organizational objectives were investigated among 201 employees of the Nigeria brewery.
Various statistical analytical procedures were applied to validate the samples and address
the study's objectives. Results show that HRM practices is significantly associated with
achieving organizational objectives. It also shows that, improving the quality of work induces
certain behaviours in the employee who is a source of competitive advantage for the
organization.
Introduction: Organisational culture has become increasingly prominent in all sectors of industry. It is
proposed that if improvements in performance and quality of work are to be achieved, basic
and procedural changes must be accompanied by changes in culture. Therefore, there
arose a need for a better understanding about the nature of organisational culture and how it
can be explored for organisation's advantage. The study adopted a survey design whereby
questionnaire was administered to 200 respondents from the banking sector. The study
used items drawn from the Denison organisational culture survey to measure culture and
effectiveness. The findings from the study showed that the response rate is 90% and that
mission has the strongest contribution to culture.
Introduction: In order to increase employee morale in organizations, it is necessary to create appropriate
foundation in the organizational environment. In such organizations, where effective factors
in the building of employees morale, are implemented completely and correctly, efficiency
has been observed to be at its peak. The research provides reward techniques for business
organization to understanding what motivate employee through remuneration practices of
the organization. The research followed an in depth questionnaire administered to
employees of a telecommunication organization. The result suggested that a careful
consideration of job security, prospect of career progression apart from monetary rewards is
essential for organizational development and change in employee initiative and boost in
employee morale.
Introduction: The current outlook of business has endorsed to the fact that human resource is the most
attractive and valuable asset of an organization. Moreso, this realization could further be
strengthened by the use of Human resource information system (HRIS). It is a
transformational tool for HR managers that serve as a connection between operations and
implementation. The study investigated the relationship between human resource
information system and human resource management (HRM) practices. Data was collected
from employees in the management levels of Food and Beverage firms in Nigeria. The result
shows HRIS influences HRM practices with improvement in communication, decision-
making, workflow processes and it is viewed as a synergic factor that gives support to
employee in the achievement of competitive advantage.
Introduction: The effect of storage conditions on the microbiological qualities of oils extracted from selected oilseeds was investigated. Oils were stored at room temperature, display condition and refrigeration temperature. The highest bacterial count was observed in Groundnut oil and soybean oil and the least in cashewnut oil with the oil stored under display condition having the highest count. On the contrary, cashewnut oil had the highest fungal count and soybean oil the least. The microbial profile of the associated organisms consists of Bacillus subtilis B. licheniformis, Proteus vulgaris, P. mirabilis, Aspergillus niger and Rhizopus spp. The slightly elevated microbial count of oils stored under display conditions in the present work seems to be suggesting that the use of antioxidants with antimicrobial property may be helpful in slowing down microbial growth and deteroration in the oils exposed to similar conditions in most Nigerian markets.
Introduction: Soybean (Glycine max [L.] Merrill) is an important oriental crop whose agronomic characteristics were apparently well known in China before 2200 BC. It is a legume that grows in tropical, sub tropical and temperate climates.
Introduction: The effect of cassava starch and corn starch on the consumers` acceptability and shelf- stability of soy-yoghurt was investigated. Three batches of soy-yoghurt were prepared using corn starch, cassava starch and gelatin as stabilizers, while the fourth batch served as control. All the batches were organoleptically evaluated and stored at 6 ± 2°C for 16 days and were subjected to physical examination and chemical analyses such as pH, titratable acidity (TTA) and microbial counts. All the stabilizers prevent whey separation. A putrid/offensive odour developed in all yoghurt samples from the 8th day of storage; while gas production was observed in all stabilized soy-yoghurt samples. For both pH and TTA, there was significant difference (P<0.05) between all the treatments and the length of storage. Microbial counts increased within first four day of storage and this was followed by a decrease. Gelatin stabilized soy-yoghurt was rated best, followed by cassava starch stabilized soy-yoghurt. Result from the present study suggests cassava starch as a probable alternative stabilizer in soy-yoghurt production.
Introduction: Adelodun. Lawrence. Kolapo
13.18Augustine University Ilara-Epe, Lagos. Nigeria
Morenike Olayinka Sanni
10.05Ajayi Crowther University
Abstract
Gari and tapioca are storage-cupboard convenience foods obtained from the tubers of cassava (Manihot esculenta Crantz). They are important staples in Nigeria and many African countries where malnutrition is a major problem. Tapioca is a quick-cooking food made from partly gelatinized starch and gari is a fermented, roasted, granular food made from cassava pulp. Gari and tapioca are nutritionally inferior and need to be fortified. This paper reports the macro- and micronutrient profiles of soybean-fortified gari and tapioca. Gari and tapioca were fortified with soybean flour or soybean residue at 25% of dry weight. Standard methods were used for the determination of proximate parameters such as crude protein, fat, ash, carbohydrate and moisture content. All the samples were analyzed for phosphorus, calcium, magnesium, potassium, sodium, manganese, iron, copper and zinc. Unfortified tapioca had significantly lower (p < .05) proximate values (protein: 0.31%; fat: 0.17%; ash: 0.34%) than unfortified gari (protein: 1.50%; fat: 1.56%; ash: 1.35%). The fortification of both gari and tapioca significantly (p < .05) increased the contents of crude protein, phosphorus, fat, and ash as well as all the monitored macro- and micronutrients. These values (%) increased from 1.50-9.31, 0.06-0.11, 1.56-4.31 and 1.35-1.64 for gari-soybean fortified gari; and 0.31-12.56, 0.03-0.12, 0.17-5.45 and 0.34-1.41 for tapioca to soybean fortified tapioca respectively. Soybean flour increased the nutrient content of the fortified gari and tapioca compared to soybean residue. Data from this study suggest that both soybean flour-fortified tapioca and soybean flour-fortified gari are effective means of meeting the daily requirements of minerals, protein, and energy. Both soybean flour-fortified tapioca and soybean flour-fortified gari could be used to fight macronutrient and micronutrient deficiencies, not only in Nigeria and other African countries where these two cassava products are staples, but also in other cassava-consuming developing nations.
Introduction: An increased use of fermented soybean (Glycine max L. Merill) as soyiru similar to iru (daddawa) from Locust beans - Parkia filicoidea will enhance nutrition. Soybeans are susceptible to fatty acid oxidation and peroxidative changes. Seed of soybean variety TGX 1440-2E were fermented using a standard 3-day procedure and the ensuing soyiru was stored for 14 days under ambient and refrigeration temperatures of 30±1 0C and 6±1 0C respectively. Proximate evaluation, pH, titratable acidity (TA), peroxide value (POV), Free fatty acids (FFA) and Ascorbic acid Antioxidant capacity (AEAC) were determined in triplicate. The proximate composition of soyiru was 6.07% crude fat, 15.97% crude protein (Nx6.25), 9.96% carbohydrate with 41.46 mg kg-1 reducing sugar, a dry matter of 35.6% corresponding to a moisture content of 64.4 %; 1.96 % crude ash and 1.64 % crude fibre. At ambient storage pH increased with reduction in TA, indicating alkaline fermentation while with refrigeration, pH decreased with increasing TA, underscoring acid fermentation. Carbohydrate content, reducing sugar content and FFA decreased with storage while moisture content and POV increased. AEAC increased from 140 to 290 mg100g-1 respectively with processing but decreased to 25 and 155mg 100g-1 respectively with ten days refrigeration and ambient storage. For both storage conditions, FFA content decreased while POV increased. A `house-fly test confirmed signs of approaching spoilage on the fourth day and sixth day of ambient and refrigerated storage, respectively. From these results, it seems that peroxidation is a key biochemical factor in spoilage of soyiru and that the product is perishable and should be used fresh.
Introduction: Many soy products have limited consumer acceptability in the Western hemisphere due to undesirable off-flavour. The possibility of enhancing the sensory attributes of soy yoghurt through the use of composite soymilk was investigated. The effect of using starter cultures from different sources on the chemical characteristics and consumer acceptability was also studied. Soy milk containing 0, 10 and 20% coconut milk were used in the production of soy yoghurt using commercially available yoghurt starter and starters isolated from naturally fermenting soy milk and cow milk. Chemical and sensory characteristics of soy yoghurts obtained were evaluated. The pH of the yoghurt premixes at the beginning of fermentation ranged between 6.25 and 6.45; after fermentation the values were between 4.81 and 5.51 with commercially available starter bringing about greatest pH reduction. Chemical compositions of obtained soy yoghurts were as follows: titratable acidity as %lactic acid (0.25-0.43%), crude protein (2.66-3.62%), fat content (0.13-0.89%), total solid content (7.91-9.06%). Variation in premix formulation had no significant (P>0.05) effect on the chemical composition of different soy yoghurts obtained. Addition of coconut milk to soy milk improved the sensory characteristics of soy yoghurts with the premix containing 10% coconut milk fermented with starter obtained from cow milk producing yoghurts with the best taste, aroma, and acceptability. Results from the present study have demonstrated a further way of enhancing soy yoghurt acceptability by the western 'palate'.
Introduction: This study was carried out to investigate the effect of ginger extract on peroxidation, free fatty acid and microbial load in stored soybean dawadawa
Introduction: Both the qualitative and quantitative aspects of phytochemicals and inorganics of the ethanolic extracts of three Nigerian chewing sticks, namely, Pseudocedrela kotschyi, Anogeissus leiocarpus and Terminalia glaucescens were investigated. Alkaloid, Glycoside, Steroid, Phenol, Tannin and Saponin were present in the three samples investigated. Anthraquinone was present in all the three samples except T. glaucescens. Fluoride was present in all the samples except P. kotschyi, while A. leiocarpus is the only sample that contained calcium. Fluoride ions ranged between 0.08 and 0.09%. Alkaloid varied between 0.42 and 1.46%, steroid between 0.10 and 0.19% and phenol between 1.55 and 1.80%. The amount of Tannin was between 0.01 and 1.70% while saponin ranged between 0.02 and 0.18% and glycoside between 0.14 and .15%. The amount of anthraquinone in P. kotschyi, and A. leiocarpus was 0.17%. The extracts of the three chewing sticks had no activity against Candida albicans. Extracts of A. leiocarpus and T. glaucescens showed appreciable bioactivities against Staphylococcus aureus and Streptococcus pyogenes. Results from the present study give some insights on the phytochemicals that could be responsible for the exhibited antimicrobial activities of the test chewing sticks; an information that would be pivotal to the development of herbal tooth paste.
Introduction: The effect of cassava starch and corn starch on the consumers' acceptability and shelf- stability of soy-yoghurt was investigated. Three batches of soy-yoghurt were prepared using corn starch, cassava starch and gelatin as stabilizers, while the fourth batch served as control. All the batches were organoleptically evaluated and stored at 6 ± 2°C for 16 days and were subjected to physical examination and chemical analyses such as pH, titratable acidity (TTA) and microbial counts. All the stabilizers prevent whey separation. A putrid/offensive odour developed in all yoghurt samples from the 8th day of storage; while gas production was observed in all stabilized soy-yoghurt samples. For both pH and TTA, there was significant difference (P<0.05) between all the treatments and the length of storage. Microbial counts increased within first four day of storage and this was followed by a decrease. Gelatin stabilized soy-yoghurt was rated best, followed by cassava starch stabilized soy-yoghurt. Result from the present study suggests cassava starch as a probable alternative stabilizer in soy-yoghurt production.
Introduction: Some functional properties were used to assess and compare biochemical deterioration in stored locust bean daddawa and soybean daddawa which are two popular fermented Nigerian condiments. The condiments were stored for 14 days at ambient temperature after the normal 72 h of fermentation and at 2 days interval assessed for pH, titratable acidity, free fatty acids (FFA), peroxide values (POV) as well as fat and water absorption capacities. The pH of both samples increased in the alkaline range, so also the titratable acidity. Peroxide values and FFA of the two condiments also increased significantly with storage, with those of soybean daddawa being significantly (p<0.05) higher. Water and fat absorption capacities of the fermented products decreased with storage. Differences recorded in values of fat absorption capacities was also significant (p<0.05). The implications of the recorded values of fatty acids, peroxidation and other functional properties monitored are discussed in relation to the perceived faster deterioration and poor acceptance soybean daddawa.
Introduction: Defatted ground nut, soybean and palm kernel cakes were stored for three months at ambient, refrigeration and display conditions. Samples were assayed for nutritive, aflatoxins and microbiological properties. Proximate parameters significantly (p<0.05) reduced with storage. Mineral composition reductions of 3.0-35.00%, 1.2-18.75% and 6.2-64.25% were observed for ambient, refrigeration and display condition storage respectively. There was a significant (p<0.05) increase in both bacterial and fungal counts with increased storage duration. Aflatoxin B1 contents of 21.65-49.26, 14.57-27.24 and 29.14-61.32 ?g/kg were detected in cakes stored at room, refrigeration and display condition respectively while the Aflatoxin B2 contents were 9.8514.13, 3.24-10.02 and 12.96-17.04 ?g/kg respectively. Proper storage/handling of feed ingredients should form a core component of Good Manufacturing Practice (GMP) of feed production in tropical countries. The regulatory agencies in these countries should enforce a revised GMP in order to guarantee a more healthy and productive populace.
Introduction: Solanecio biafrae (Olive and Hierne) C. Jeffrey (1986) (Family: Asteraceae), has synonyms Senecio biafrae Olive and Hierne (1877) and Crassocephalum biafrae (Olive and Hierne) S. Moore (1912). It is a perennial standent, underutilized African indigenous medicinal vegetable. It was first reported and published in Flora of Tropical Africa. Its common names varied from Gnanvule in Cote d'Ivoire to Worowo/bologi in Nigeria. It has alternate, simple, succulent, petiolated, and exauriculate leaves. Its propagation is vegetative by rooting of cuttings. However, there is no report on its propagation by seed. It is ubiquitous in cocoa plots in Nigeria, especially southwest; due to deliberate protection for economic revenue, but this has little-uncoordinated cultivation indication. These deliberately protected few are exposed to contamination by a chemical used for protecting cocoa plants. It is highly nutritive and rich in protein. It is also medicinally important as a galactagogue and for treatment of diabetes, high blood pressure, and infertility. It has biological activity against Staphylococcus aureus and Escherichia coli. It also has traditional and cultural claims for initiation and rituals. Personal interviews and search of the available literature on S. biafrae in electronic peer-reviewed English journals using scientific databases such as Google Scholar, Science Direct, PubMed, Scopus, and Web of Science was employed.
Introduction: The in vitro and in vivo assessment of antimicrobial activities of some commonly patronised toothpastes and mouth washes in Nigeria against some oral pathogens was carried out. The pathogens used include Streptococcus mutans, Enterococcus faecalis and Candida albicans. On the basis of a survey amongst two hundred people, seven toothpastes and three mouthwashes were selected for assessment. Different concentrations (50%, 25%, 12.5%, 6.25% and 3.175%) of the selected toothpastes and mouthwashes were prepared with sterile saline (0.9%); these and undiluted samples were used immediately for the in vitro testing using standard procedures. The in vivo study involved ten groups of people (a group per sample), with each group consisting of five volunteers. Mouth rinses were collected from the volunteers before and immediately after using the dental care product, as well as at 30, 60, 90 and 120 minutes after initial mouthwash. Viable counts were carried out on the mouth rinses and results expressed as log cfu/ml. For the three organisms used, the in vitro growth inhibition was dependent on both the sample used and the concentrations tested.
Introduction: G R Oladimeji
Adelodun. Lawrence. Kolapo
13.18Augustine University Ilara-Epe, Lagos. Nigeria
Abstract
Studies were carried out to evaluate the proximate changes and microbiology of stored defatted residues of some oilseeds in Nigeria. Oilseeds studied include Melon (Colocynthis citrullus), Soybean (Glycine max), Cashew (Anacardium occidentale), Groundnut (Arachis hypogeae) and Coconut (Cocos nucifera). On a general note, the proximate parameters such as % protein, % ash, % ether extract, % carbohydrate and % moisture decreased in all the stored defatted residue, with melon residue recording the highest decrease(protein: 48.1 -42.1%; Ether extract: 19.2 -18.0%; Carbohydrate: 10.2 -9.6%) while coconut residue had the lowest decrease(protein: 19.9 -19.2%; Ether extract: 16.2 -15.8%; Carbohydrate: 28.6 -26.7%). There was a significant difference (P < 0.05) in both the total bacterial count (TBC) and total fungal count (TFC) within the period of storage. On melon residue TBC increased from 10.51 log10 to 12.11 log10 cfu/g and TFC from 8.45 log10 to 10.17 log10 cfu/g. However on coconut residue TBC increased from 10.41 log10 to 11.48 log10 cfu/g while TFC increased from 8.41 log10 to 9.30 log10 cfu/g. Prominent organisms isolated include A. niger, Rhizopus spp, Bacillus. subtilis, B. licheniformis and Proteus mirabilis .The effect of proliferation of the isolated organisms on the storage qualities of these defatted residues may have been responsible for the reduction in the nutritive value of the stored residues. Results from these studies have revealed that the storage qualities of the defatted residue are time dependent.
Introduction: Abstract Objectives: This study focused on improving and diversifying the food and nutrition situation of low income families in the developing world by initiating the production of soy-corn milk and evaluating its quality and potential for acceptance. Methodology and Results: Soy-corn milk was produced from 75% soybean and 25% maize. Milk samples were analyzed for protein, moisture, ash, fiber and fat contents, microbiological assays and sensory attributes. The protein, fat, ash and total solid contents of soy-corn milk were 4, 4.14 1.23 and 12.2%, respectively while those of soymilk were 3.15, 3.42, 1.17 and 11.23%, respectively. Fortification of soymilk with corn did not produce any significant changes in the microbial count and profiles of soy-corn milk. However, adding maize to soybean for the production of soy-corn milk significantly (P<0.05) improved its taste, aroma, consistency and overall acceptability when compared with soymilk. Application of findings: Addition of maize to soybean for the production of soy-corn milk added value to the product through increased nutrient content and sensorial attributes. Being cheaper and readily available, increased adoption of soy-corn milk would increase milk availability to low-income families in the developing world.
Introduction: Abs t ra c t The possibility of enhancing the sensory attributes of soy yoghurt through the use of composite soymilk was investigated. The effect of using starter cultures from different sources on the chemical characteristics and consumer ac-ceptability was also studied. Soy milk containing 0, 10 and 20% coconut milk were used in the production of soy yoghurt using commercially available yoghurt starter and starters isolated from naturally fermenting soy milk and cow milk. Chemical and sensory characteristics of soy yoghurts obtained were evaluated. The pH of the yoghurt premixes at the be-ginning of fermentation ranged between 6.25 and 6.45; after fermentation the values were between 4.81 and 5.51 with commercially available starter bringing about greatest pH reduction. Chemical compositions of obtained soy yoghurts were as follo ws : t itratab le ac idit y as %lac tic ac id (0.25-0.43%), crude protein (2.66-3.62%), fat content (0.13-0.89%), total solid co nte nt (7.91-9. 06% ). Variation in premix formulation had no significant (P>0.05) effect on the chemical composition of different soy yoghurts obtained. Addition of coconut milk to soy milk improved the sensory characteristics of soy yoghurts with the premix containing 10% coconut milk fermented with starter obtained from cow milk producing yoghurts with the best taste, aroma, and acceptability. Results from the present study have demonstrated a further way of enhancing soy yo-ghurt acceptability by the western ‘palate’.
Introduction: ABSTRACT
Studies on phytochemical composition and antimicrobial activity of aqueous and ethanol extracts of roots and stems of Dichrostachys
cinerea against clinical isolates of Candida albicans, Streptococcus mutans and Staphylococcus saprophyticus were carried out. The main
phytochemicals present in the stem and roots included alkaloids, saponins and tannins, with roots containing the greater share. Steroids
and cyanoglycoside were present in the stem. Both ethanol and aqueous extracts of the tested chewing stick inhibited the growth of all
three tested microorganisms. There was no significant difference (P>0.05) between the inhibitory effect of the aqueous and ethanolic
extracts of the roots of D. cinerea on C. albicans. However, the ethanolic extract of the stem exhibited a significantly higher (P<0.05)
bioactivity than that exhibited by the ethanolic extract of the root. The pattern of inhibition of S. mutans and S. saprophyticus by the
extracts were similar. Solvent used in extraction did not produce any significant effect (P>0.05), but the stem extracts exhibited a
significant inhibition (P<0.05) compared to the root extract. Our results clearly show that D. cinerea is a potential candidate plant that
could be used in the development of a dentifrice.
Introduction: Abstract
Background. Gari and tapioca are storage-cupboard
convenience foods obtained from the tubers of cassava
(Manihot esculenta Crantz). They are important staples
in Nigeria and many African countries where malnutrition
is a major problem. Tapioca is a quick-cooking
food made from partly gelatinized starch and gari is a
fermented, roasted, granular food made from cassava
pulp.
Objective. Gari and tapioca are nutritionally inferior
and need to be fortified. This paper reports the macroand
micronutrient profiles of soybean-fortified gari and
tapioca.
Methods. Gari and tapioca were fortified with soybean
flour or soybean residue at 25% of dry weight. Standard
methods were used for the determination of proximate
parameters such as crude protein, fat, ash, carbohydrate
and moisture content. All the samples were analyzed for
phosphorus, calcium, magnesium, potassium, sodium,
manganese, iron, copper and zinc.
Results. Unfortified tapioca had significantly lower
(p < .05) proximate values (protein: 0.31%; fat: 0.17%;
ash: 0.34%) than unfortified gari (protein: 1.50%; fat:
1.56%; ash: 1.35%). The fortification of both gari and
tapioca significantly (p < .05) increased the contents
of crude protein, phosphorus, fat, and ash as well as all
the monitored macro- and micronutrients. These values
(%) increased from 1.50–9.31, 0.06–0.11, 1.56–4.31 and
1.35–1.64 for gari-soybean fortified gari; and 0.31–12.56,
0.03–0.12, 0.17–5.45 and 0.34–1.41 for tapioca to
soybean fortified tapioca respectively. Soybean flour
increased the nutrient content of the fortified gari and
tapioca compared to soybean residue. Data from this
study suggest that both soybean flour-fortified tapioca
and soybean flour-fortified gari are effective means of
meeting the daily requirements of minerals, protein, and
energy.
Conclusions. Both soybean flour-fortified tapioca
and soybean flour-fortified gari could be used to fight
macronutrient and micronutrient deficiencies, not only
in Nigeria and other African countries where these two
cassava products are staples, but also in other cassava consuming
developing nations.
Introduction: ABSTRACT
An assessment of phytochemical composition and antimicrobial activity of aqueous and ethanol extract of
root and stem of Terminalia glaucescens against clinical isolates of Candida albicans, Streptococcus mutans and
Staphylococcus saprophyticus was carried out. Alkaloids, saponnins and tannins are the major phytochemicals
present, with the root containing a significantly (P<0.05) higher amount of these phytochemicals. Results obtained
showed that both ethanol and aqueous extracts of the tested chewing sticks had inhibitory effect on the growth of
clinical isolates. ANOVA test of data on the antimicrobial activity of aqueous and ethanol extracts on C. albicans
revealed that the solvent used in extraction procedure had significant effect (P<0.05) on the level of inhibition
observed. In addition, the root extracts exhibited a significantly higher inhibition on C. albicans compared to
the effect produced by the stem extract. The inhibitory effect of the extracts on Streptococcus mutans and
S. saprophyticus showed no significant difference (P>0.05) between extract concentration. The effect exhibited by
ethanol extract was significantly higher than that produced by aqueous extract. However, the length of incubation
produced no significant effect (P>0.05) on the degree of inhibition of S. mutans by the root and stem extracts.
Results from the present study have shown that T. glaucescens has great potential in dentifrice production.
Introduction: ABSTRACT
Studies on phytochemical composition and antimicrobial activity of aqueous and ethanol extracts of roots and stems of Dichrostachys
cinerea against clinical isolates of Candida albicans, Streptococcus mutans and Staphylococcus saprophyticus were carried out. The main
phytochemicals present in the stem and roots included alkaloids, saponins and tannins, with roots containing the greater share. Steroids
and cyanoglycoside were present in the stem. Both ethanol and aqueous extracts of the tested chewing stick inhibited the growth of all
three tested microorganisms. There was no significant difference (P>0.05) between the inhibitory effect of the aqueous and ethanolic
extracts of the roots of D. cinerea on C. albicans. However, the ethanolic extract of the stem exhibited a significantly higher (P<0.05)
bioactivity than that exhibited by the ethanolic extract of the root. The pattern of inhibition of S. mutans and S. saprophyticus by the
extracts were similar. Solvent used in extraction did not produce any significant effect (P>0.05), but the stem extracts exhibited a
significant inhibition (P<0.05) compared to the root extract. Our results clearly show that D. cinerea is a potential candidate plant that
could be used in the development of a dentifrice.
Introduction: bstract
Objectives: Yorghurt quality, as affected by combining cow milk with soy milk and using starters from different sources, was investigated. Methodology and Results: Premixes containing soy milk, cow milk and soymilk-cow milk (50:50) were used to produce yoghurt using commercially available starter cultures or cultures isolated from naturally fermenting soy milk and cow milk. Chemical and sensory characteristics of the yoghurts were evaluated. pH values of the yoghurt samples were between 4.10 and 4.94, titratable acidity varied between 0.15 -0.33%, crude protein content was 3.50 -12.40%, fat content between 0.13 -2.67% and the total solid content was between 8.24 -23.4%. Combining cow milk with soymilk significantly (P<0.05) increased the total solids, protein, ash, fat and carbohydrate contents of the yoghurt. Yoghurt from cow milk premixes was most preferred, while that from plain soymilk was least accepted. However, addition of cow milk to soymilk significantly (P<0.05) improved the sensory attributes of yoghurt produced from soymilk. Starter cultures isolated from cow milk gave better yoghurt irrespective of the starting premix. Conclusion and application of findings: The results demonstrate that soy yoghurt adoption could be enhanced by premix modification and that production of soy yoghurt with acceptable quality needs a careful selection of starter culture. If soy yoghurt could become more acceptable it could help to fight malnutrition and hunger in developing countries. Citation: Olubamiwa OO. and Kolapo AL, 2008. Production of yoghurts from cow and soy composite milk using starter cultures from different sources. Journal of Applied Biosciences 6: 158 – 163. Introduction The different types of food groups that are traditionally included in meals are milk, meat, vegetables, fruits, bread and cereals. Unfortunately, milk and its products hardly feature among the major food items consumed in developing countries (Ene-Obong, 2001), especially in the diets of low income families which consist mainly of starchy staples. Animal sources of proteins which could be used to compliment the starchy foods are expensive and out of reach for low income families (Obatolu et al., 2007). This poor state of access to nutritious food in developing countries is being addressed through efforts such as the Millennium Development Goals.
Introduction: In this study, porous activated carbons (AC) were synthesized by an environmentally friendly technique involving chemical activation and carbonization, with an in-depth experimental study carried out to understand the electrochemical behaviour in different aqueous electrolytes (KOH, LiCl, and Na2SO4). The electrochemical performance of the AC electrode was evaluated by different techniques such as cyclic voltammetry, galvanostatic charge/discharge and impedance spectroscopy. The results obtained demonstrate that the AC materials in different electrolytes exhibit unique double layer properties. In particular, the AC electrode tested in 6 M KOH showed the best electrochemical performance in terms of specific capacitance and efficiency. A specific capacitance of 129 F g?1 was obtained at 0.5 A g?1 with a corresponding solution resistance of 0.66 ? in an operating voltage window of 0.8 V, with an efficiency of ?100% at different current densities.
Introduction: Meloidogyne incognita are serious pests of Abelmoschus esculentus cultivation in Nigeria. Generally control has relied on the use of synthetic nematicides, however excessive use of pesticides in controlling them has led to the development of resistance by the organism. Environmental persistence of metabolites has resulted in pollution of surface and underground water. There is need to develop safer pesticides from natural plant metabolites. Extracts of Anacardium occidentale bark were obtained by cold extraction using ethanol. Phytochemical screening was conducted and the unique chemical constituents were identified using Thin Layer and Column Chromatography methods. The results of the phytochemical analysis revealed phyto-constituents like phenols
Introduction: An ethnobotanical survey was carried out in Ijebu – North Local Government Area of Ogun State to document the plant species used in the treatment of benign prostatic hyperplasia within the area. According to modern ethnobotanical practices, structurally designed questionnaires were administered to those with knowledge about these medicinal plants, and their responses were properly documented. A total of thirtyone (31) plant species from twenty-nine (29) genera and twenty-six (26) families were reported as useful in the treatment of the ailment. While Annonaceae, Caesalpiniaceae, Euphorbiaceae, Moraceae, and Poaceae are all represented by two species, others are represented by only one. The recipes, methods of preparation and administration were also properly documented in this work. Ananas comosus and Garcinia kola were both useful in the preparation of at least two recipes, which is indicative of their importance in herbal and traditional medicine. This study suggests that further phytochemical and pharmacognostic studies should be conducted to ascertain the potencies of these medicinal plants.
Introduction: This study focused on the Child Rights Act and how relevant stakeholders, institutions and agencies have been able to guarantee the attainment of these rights through budgetary provisions. Therefore, the main objective of this study is to determine the effects of public healthcare expenditure on the attainment of these rights. To this end, the study employed the Grossman human capital development model and fitted a time series data obtained from World Development Indicators and CBN statistical bulletin using OLS and TSLS. In the process, we observed that public healthcare expenditure has been on the increase, while the under-five mortality rate has been falling but not in the same proportion. Secondly, we observed that public healthcare expenditure is statistically significant with under-five mortality rate but with an infinitesimal magnitude of 0.017% (OLS) and 0.035% (TSLS). Public education expenditure is positively but has no statistically significant relationship with primary school enrolment. It was discovered that the incidence of mortality is higher than the child school enrolment. The findings also show that location and accessibility to both health and education facilities are important in explaining under-five mortality and primary school enrolment respectively. We therefore suggest that more proportion of the public healthcare expenditure should be allotted to the welfare of the under-five, thereby fulfilling the Child Rights Act.
Introduction: Social network theory is an appropriate theory for understanding the relationships among the different parties in the supply chain. This article adopts the conceptual-theory framework to introduce arm's-length and close ties concepts into the field of supply chain risk management. The theoretical paradigm of social network theory is used to develop a framework and propositions for future empirical studies. Specifically, this conceptual article uses the idea of the social network theory to propose the need for firms to incorporate both the close and arm's-length ties in their supply chains. This approach of combining the two forms of ties as a composite tie within a supply chain could serve as an important supply chain risk management tool in relation to supply chain disruption and its mitigation, because of the synergistic benefits.
Introduction: This paper reviews the supply chain management literature to summarize best-practice guidelines for mitigating supply problems. Very few studies in the extant literature focused on matching a strategy for both the supply and demand perspective. Case studies of supply chain management have traditionally focused on single companies, and especially on successful organizations rather than on the demand-supply-chain relationships (which involve at least two companies). Therefore, this study considers the experiences of the author, and researchers several well-known profitable fortune 1000 supply chain companies, to determine which supply chain mitigation strategies work best in complex situations. International Journal of Risk and Contingency Management, 1(3), 45-58, July-September 2012 45
Introduction: This paper examines the Messe and Rogoff claim of the superiority of random-walk model in the determination of exchange rate in the light of more recent models and empirical results. Random walk model is the traditional model of exchange rate determination while the recent models include the purchasing power parity (PPP), the monetary model and portfolio model. Empirical evidence against the dominance of random-walk in forecasting the behaviours of exchange rate seems to be large or rather inconclusive, since the main thrust of some of the findings is that Messe and Roggoff used out-of-sample test with shorter time horizon which does not have a good econometric justification. Although it cannot be absolutely concluded that economic models are useless in the determination of exchange rate, the relevance of a model in the determination of exchange rate depends on the combination of different factors which vary with time and place.
Introduction: This study investigates the linkage between fiscal policy and poverty reduction in Nigeria using a descriptive analysis. It explores the effectiveness of fiscal policy tool, especially government expenditure, in addressing the level of poverty and economic growth in the country. The study found that government capital and recurrent expenditures have not significantly reduced the levels of poverty in Nigeria because of a weak linkage, which has not allowed fiscal policy to reflect its true opportunity cost. This gap created loopholes in the implementation of the various measures of fiscal policy in the country. The study therefore concludes that the level of government capital expenditures in Nigeria have weak impact on the level of poverty in the country over the period of time covered. The study therefore recommends the formulation of stable macroeconomic policies that are consistent with the peculiarity of poverty situation in the country. This would promote productivity from which both the poor and non-poor would benefit.
Introduction: Using a multiple regression analysis in the autoregressive distributed lag framework with ECM we include three major components of fiscal policy variables (Government capital expenditure, Government recurrent expenditure and Government Budget Deficit) as regressors and the rate of poverty in Nigeria as the dependent variable, this study explored the potency of fiscal policy in Nigeria in addressing the seemingly endemic poverty scourge from 1980-2011. Findings indicate that the level of government capital expenditures in Nigeria does not reduce the level of poverty in the country over the period of time covered by the study. Although the ECM result, which shows the speed of adjustment of the model from the short run to the long run equilibrium, is on the average, yet the economy did not show any sign of much potency in using the selected fiscal policy variables to tackle the menace of poverty in Nigeria. The study recommends that government should intensify action in implementing effective fiscal policies to ameliorate the level of poverty conditions in Nigeria.
Introduction: This study examines the exchange rate trends and export performance in Nigeria between 1970-2015 using a descriptive approach. Particularly, the study emphasizes the impacts of exchange rate volatility on export demand in the country. The choice of this period is underscored by the fact that the starting date predates the era of the structural adjustment program (SAP) which is often described as the good days where agricultural and non-oil exports tremendously increased. Again, this date coincides with period when the external trade and exchange rate were indeed liberalized. Findings from descriptive analysis show that despite the policy pronouncements in the period covered, exchange rate volatility greatly affected export performance in Nigeria, in particular, the volume of export demand. The study recommends a deliberate exchange rate policy action that will have good implication for export growth in Nigeria
Introduction: Most of the existing papers in Nigeria that address links between monetary policy management and banking sector
performance used various econometrics and inferential statistical measures, with little or no concern for readers that are not
quantitatively biased. Therefore, this paper characterized the trajectory paths of the dynamics of the performances of key
monetary policy tools and banking sector performance indicators spanning 1985-2011. We found that despite the various
financial sector reforms in Nigeria at the wake of global financial crisis, which has led to increase in the trends of some of
these indicators, the widespread in the interest rate margin (high lending rates given by banks to investors and low deposit
rates given to the depositors) has decelerate the pace of financial development and lower pace of economic growth as a result
of lack of incentives to depositors, hence, their preference for other informal savings arrangements. Strengthening the
monetary authority in Nigeria will therefore help in addressing these anomalies.
Introduction: This study examines the impacts of interest rates on private consumption behaviour in Nigeria
between the period of 1981 and 2013 using autoregressive distributed lag (ARDL) cointegrations
framework. The data were sourced from the World Bank development indicators and the
interest rate was augmented with other macroeconomic variables like per capita income, money
supply, and banking sector credit to the private sector as regressors in determining the
behaviour of private consumption in Nigeria. The results confirm the existence of a relationship
between private consumption and its determinants, except real interest rate and the dummy for
the impact of interest rate deregulation. The study, therefore, recommends an increase in
government capital expenditures that will create an enabling env
Introduction: Four new species of Baphia are described from the part of Africa around the Gulf of Guinea.
Introduction: As part of a multidisciplinary approach to a revision of the genus Baphia a comparative study of the leaf epidermis of 78 taxa of this genus and related genera using the light and scanning electron microscopes was undertaken. Variation observed in cell shape, anticlinal cell wall pattern, cell size, cell wall thickness, trichomes, papillae, stomata complex and wax are discussed and their taxonomic implications if any are noted. Of necessity, several figures are presented to explain the variations in those characters mentioned above.
Introduction: The petiole anatomy of 79 specimens representing 64 species of Baphia has been examined. Anatomical characters of the petiole provide supporting evidence to be used in the infra-generic classification of the genus. They correspond to systematic groupings identified on other criteria, such as comparative morphology, palynology and phytogeography.
Introduction: The pollen grains of 104 specimens representing 60 species of Baphia have been examined using light, scanning and transmission electron microscopy. Ten pollen types are recognized, and some correlate broadly with groups of species identified by other characters. The systematic implications of the pollen morphological data are discussed. Two main trends in exine stratification are recognized. One involves extreme thinning of the endexine, the other, thickening of the endexine associated with a thinner ectexine and loss of the foot layer. We suggest that the extremes of both trends confer different responses to forces generated in harmomegathic movements.
Introduction: The genus Baphia Lodd, of the tribe Sophoreae of Leguminosae subfamily Papilionoideae is revised throughout its range in Africa and Madagascar. The 45 species recognised are keyed out, described and mapped, with appropriate bibliography, notes on ecology and distribution, and a list of collection numbers. The generic and infrageneric classification is discussed, together with an analysis of the ecology and phytogeography.
Introduction: Some selected staple foods: tubers, cereals, and legumes, grown, sold and consumed in Ijebu-North
Local Government area, Nigeria were evaluated for their iodine content using standard methods.
Among the tubers, Ipomea batata (sweet potatoe, red species) was observed to have the highest iodine
content (311.33±8.52 µgI) while the least iodine value of 88.97±1.31 µgI was recorded in Discovea
avenmensis (cocoyam). Among the cereals, maize was observed to have the highest iodine content
(100.96±3.50 µgI). When the iodine content of the legumes was compared, the highest was observed in
Glycine soja (soybean; 179.56±4.66 µgI) while the least was in Cucus melo (mellon; 29.84±1.21 µgI).
Result from our findings indicated that most of the staple foods contain high level of iodine
Introduction: Abstract: The relationship among five species of Acalypha Linn. (Euphorbiaceae) is described using phytochemical and quantitative morphological parameters based on herbarium and field collections. Preliminary phytochemical study revealed the presence of alkaloids, tannins, saponins and cardenolides in the five species. These secondary metabolites might be responsible for the frequent use of these species of Acalypha in Traditional medicine. The results of the multivariate analyses (Principal Component Analysis (PCA) and Cluster analysis) show that two of the nine quantitative parameters account for the differences among the taxa. A. hispida was found to be more closely related to A. fimbriata. A. hispida and A. wilkesiana share some resemblances. The affinity between A. ornata and A. fimbriata was stronger with 21.082 coefficient of agglomeration than the affinity between A. ornata and A. hispida with 1224.099 coefficient of agglomeration.
Introduction: The conservation of the genetic variability of the indigenous angiosperm community is a sine qua non.
A survey of indigenous angiosperm biodiversity of the Olabisi Onabanjo University permanent site was
undertaken. Plants collected were dried, poisoned and mounted on herbarium sheets, proper
identification and confirmation in recognized herbaria were carried out. A total number of one hundred
and thirty-eight (138) plant species belonging to fifty-five (55) families were collected. Of these, one
hundred and twenty-seven are dicotyledons and eleven are monocotyledons. Leguminosae is the
largest family with thirteen plants followed by Rubiaceae with eleven and Euphorbiaceae with nine
plants. Trees were found to have significantly contributed to the ecosystem with a total number of fiftyfour
species, while forty-three of shrubs were recorded, climbers ten, herbs twenty-eight, grasses and
sedges three. From this study it is obvious that the University permanent site is not only rich in plant
biodiversity but also very rich in socio-economic values. Consequently it is highly advisable that a
representative sample of this vegetation is protected for posterity so that all the indigenous
Introduction: The in-vitro antimicrobial evaluation of ethanol extracts of four species of Cola Schott & Endl. was done using human isolated strains of Staphylococcus aureus, Staphylococcus albus, Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger as test organisms. The assays were carried out by agar well diffusion, erythromycin and ketoconazole served as the control drugs. The leaf ethanol extracts of the plants were found to be more effective against the tested fungi than the bacteria at high concentrations. None of the extracts was active against Staphylococcus aureus. Plant extract of C. acuminata (P. Beauv.) Schott & Endl. and C. nitida (Vent) Schott & Endl. showed activity on S. albus at concentrations ranging from 10–150 mgml? having comparable diameters of zone of inhibition of 7.3±0.03–16.0±0.0 for C. acuminata and 10.0±0.0–19.0±0.0 for C. nitida. Also, these two species of Cola demonstrated activities on C. albicans and A. niger at concentrations ranging from 90–150mgml?1 with relatively close diameters of zone of inhibition. Only C. acuminata inhibited the growth of K. pneumoniae at the MIC of 90mgml?1 whereas, C. albicans was inhibited by C. acuminata, C. millenii K. Schum and C. gigantea A.Chev. at the MIC of 120mgml?1. Phytochemical screening of the four species of Cola showed the presence of alkaloids, saponins, tannins and cardenolides in all the plants which apart from showing the probable closeness of the species could also be responsible for the observed activities. The antimicrobial property shown by the plant extracts is an evidence of the ethnomedicinal uses of the plants. The similarity observed in the phytochemical constituents and antimicrobial activities demonstrated by C nitida (Vent.) Schott & Endl., C. millenii and C.gigantea A. Chev. and C. acuminata suggest a probable closeness among these species. The results obtained in this study provide preliminary evidence of the chemotaxonomic significance
Introduction: Thirteen quantitative characters of the leaves, fruits, seeds and flowers were used in the study of eight
Senna Mill. species. The characters include leaflet length, leaflet width, leaflet length/width, Number of
leaflets, lamina length, petiole length, pedicel length, petal length, fruit length, fruit width, fruit
length/width, seed length and seed width. These characters were measured with the aid of a line ruler
and subjected to principal component analysis (PCA) and cluster analysis. The results revealed that
three out of the thirteen characters employed contributed significantly in differentiating each of the
species from the other at 95% level of significance. The species have great similarities hence their
grouping under the same genus. Results also showed that Senna hirsuta (Linn.) H. S. Irwin and
Barneby and Senna sophera (L.) Roxb. are more closely related, Senna occidentalis (Linn.) Link, Senna
siamea (Lam.) H. S. Irwin and Barneby and Senna spectabilis (DC.) Irwin and Barneby all share some
resemblance while S. occidentalis is distantly related to S. sophera.
Introduction: A survey of the weed flora of the campus sites of the Olabisi Onabanjo University was undertaken. Several visits
were made to the disturbed and undisturbed vegetation of the sites for collection of weeds after which the weeds
were prepared in accordance with conventional herbarium practice. A total of seventy-three (73) weed
species belonging to twenty-seven (27) families were identified and found to be present within the area of study.
The family Poaceae seems to have the highest number of weed species (twelve) available within the area followed
by Asteraceae with ten (10) species. Amaranthaceae, Cyperaceae and Euphorbiaceae are also in abundance.
These weeds have been discovered to be useful, against the mindset of the uninformed that they are useless
or ‘vagabond’ plants. Medicinal uses as well as percentage occurrence of each family are presented. From this study
it is obvious that the University sites are not only rich in plant biodiversity but that the plants are also very rich
in socio-economic values. It is therefore advisable that these plants should be protected from going into extinction
so that all would not be lost due to developmental activities.
Introduction: Effect of processing on iodine content of some selected plants food was investigated. Results show
significant reduction (p < 0.05) in the iodine content of the processed food compared with the raw
forms. The iodine value of 658.60 ± 17.2 µg/100g observed in raw edible portion of Discorea rotundata
was significantly higher compared with the value of 448.60 ± 2.46, 248.60 ± 2.46 and 300.05 ± 5.66
µg/100g dry matter observed in the boiled yam, pounded yam and yam flour, respectively. The result
also indicates that the iodine value of 592.50 ± 8.22 µg/100g dry matter observed in the raw form of
cassava was higher when compared with that of garri (366.03 ± 3.82 µg/100g) and cassava flour (216.90
± 1.03 µg/100g dry matter). Similarly, raw Zea mays contain higher iodine (112.24 ± 0.42 µg/100g)
compared with boiled maize (79.44 ± 0.64 µg/100g dry matter) and fresh ogi (45.07 ± 1.24 µg/100g dry
matter). The result also indicates that raw Vigina uguicnlata and Arachis hypogea contain higher iodine
content (112.22 ± 0.22 and 119.62 ± 0.22 µg/100g dry matter, respectively) when compared with their
boiled forms (97.33 ± 1.53 and 83.12 ± 1.35 µg/100g, respectively). Results obtained in this study thus
indicate that processing significantly reduces iodine content of food products, hence consideration
must be given to different processing methods when accessing Iodine intake from different processed
foods
Introduction: Ethnobotanical survey of the plants used in the treatment of Haemorrhoids was carried out in
South-Western, Nigeria. The herbalists, herb sellers and traditionalists were interviewed by the
administration of questionnaires. From the survey, a total of 143 plant species belonging to 58
families were found to be useful for the treatment. The most prominent among these plant
families is the Leguminosae family with 22 species, an indication of the utmost importance of this
family in the cure of haemorrhoids. Other plant families include Euphorbiaceae (8),
Apocynaceae (6), Meliaceae, Compositae and Poaceae with 5 species each. In all, the
commonest species in the recipes are Senna alata Linn., Gongronena latifolium Benth, Axonopus
compressus Engl. & Diels, Anogeiessus leiocarpus (D.C) Guil. L & Per, Pteleiopsis suberosa
Engl. & Diels, Tetrapleura tetraptera (Schun & Thonn) Taub, Khaya spp and Allium spp. All the
plants identified in this work have been used severally by the herbalists and adjudged to be
efficacious.
Introduction: In the past few decades, there has been renewed interest on increase in intake of fruits and vegetables,
owing to their numerous beneficial effects. The present study provides preliminary data on the ability of
different fruits and vegetables grown and consumed in Ijebu North Local Government Area of Ogun
State, Nigeria to concentrate iodine in their tissues, given the same environmental conditions. Chemical
evaluation of iodine content of some selected fruits and vegetables, grown and consumed in the area
was carried out. Out of the six fruits assessed, Musa paradisca has the highest level of iodine (258.83 ±
11.43 µg / 100 g edible portion), while the least value was observed in Citrus paradis (2.43 ± 0.01 µg / 100
g edible portion). No significant variation (P ? 0.05) was observed in the iodine content of Citrus
aurumthifolia (27.38 ± 2.16 µg / 100 g edible portions) and Musa sapientum (19.79 ± 6.23 µg / 100 g edible
portions). The iodine contents of Carica papaya and Citrus paradis were not significantly different (P ?
0.05) from each other. Out of the twenty (20) vegetables assessed, the highest iodine value was
observed in Amaranthus hubridus (58.36 ± 1.88 µg / 100 g edible portion) and the least value was found
in Talinum triangulare (0.49 + 0.01 µg / 100 g edible portions). Our result indicates that few of the fruits
and vegetables grown and consumed in the Local Government Area have the ability to concentrate
enough iodine that can sufficiently meet the required daily allowance, thus, we advise that such fruits
may need to be consumed along with some other dietary sources in order to meet the daily requirement
for iodine. Furthermore, our result suggests that the ability of fruits and vegetables to concentrate
iodine in their tissues varies from one to another.
Introduction: The relationship among seven species of Indigofera (Leguminosae-Papilionoideae) is described using eight quantitative parameters based on both herbarium and fresh specimens
Introduction: The use of Traditional medicine in developed as well as developing countries as basis for the treatment of
many ailments has been in existence for thousands of years and there is no doubt that their importance
has been widely acknowledged. The present study points out the fact that, medicinal plants have
continued to play vital roles in the Nigerian healthcare sector, although traditional medical practitioners
have not been fully recognized. Findings from this study also showed that the government is yet to
adequately contribute positively to the conservation and sustainable use of these flora species. In general,
this paper examines previously published articles on medicinal plants in Nigeria, presents the uses of
some of these plants as earlier reported, discusses the challenges facing their availability and argues for
rational conservation methods to be employed on time.
Introduction: Anacardium occidentale is a local medicinal plant used in ethno medicine for the treatment of diarrhea, constipation,pain and inflammation. The aqueous and ethanolic extracts of this plant parts were assessed for antiinflammatory and antibacterial activities using experimental animal model and agar disc diffusion methods respectively. Results show that the ethanolic extract of the plant were more efficacious than the aqueous extract in inhibiting the carrageenan induced paw oedema in rats in a non dose-dependent manner( P>0.05).No significant difference was found between the ethanolic extract of the leaves and bark (P>0.05). Also, the antibacterial activity was apparently higher in ethanolic extract than in aqueous extract for both leaves and barkwith the bark extract displaying a significantly (P<0.05) higher activity compared to the leaves extract. The results of this study therefore justify the use of this plant in the treatment of inflammation and bacterial infections.
Introduction: Background: Healthcare waste management is a major challenge, especially in primary health care facility.
This is because waste generated from this facility carries high potential for infections and injuries, yet not
many studies have been carried out on healthcare waste generated in the area studied. Inadequate management
of the waste may have serious consequences on public health. Therefore, this study was aimed at assessing
healthcare waste management practices in primary healthcare facility, with a view to proffering practical
solutions to the associated problems.
Introduction: The foliar epidermal and phytochemical characteristics of Clitoria ternatea and Centrosema pubescens are
studied in this work. Results have revealed minor differences between the examined species. A microscopic
study has shown that both species are hypoamphistomatic, have irregular cells and simple trichomes on their
abaxial and adaxial surfaces. C. pubescens has more stomata, trichomes and epidermal cells than C. ternatea,
but its stomata and epidermal cells are smaller in size. The stomata index ranges between 5.1–21.0%. On
the other hand, a phytochemical analysis has shown little difference in the amount of bioactive compounds
present in both species, except for in the flavonoid content which was significantly different between the two.
Although phytosteroidal content in the two species is also not very significant, its presence may be linked to
the species medicinal value as an aphrodisiac
Introduction: The phytochemicals in the stem and root of Cissus populnea were examined. Specimens were collected
from New Bussa, Niger State, Nigeria and identified at the Forest Herbarium Ibadan (FHI). The stem and
root were air-dried, ground into fine powder and subjected to series of phytochemical screenings. Results
revealed that both plant parts contain alkaloids, flavonoids, saponins, and tannins in large quantity. However,
the alkaloid content in the stem was the highest, with 49.8%. It was followed by flavonoids (15.4%), saponins
(12.8%) and tannins (11.6%). Similarly, there was also significant amount of flavonoids (39.5%), alkaloids
(26.7%), tannins (11.3%), and saponins (10.5%) in the root. While cardiac glycosides recorded the least
amount in the stem, phytosteroids had the least amount in the root. The occurrence and quantity of other
phytochemicals, as recorded in this study, also suggest that C. populnea may serve as a potential source of
useful drugs in the near future.
Introduction: Ethnobotanical survey of the plants used in the treatment of Diabetes mellitus was conducted in
some areas of South-Western Nigeria. The survey revealed the use of about 132 different plants
species belonging to 56 families in the treatment of Diabetes mellitus. Taxonomic practice of
specimen preparation for herbarium storage was performed for each of the plants and some
were deposited at the Elikaf herbarium of Olabisi Onabanjo University, Ago Iwoye. The
identified plants have been confirmed to posses anti-diabetic properties. Prominent among them
are Senna alata Linn, Curculigo pilosa (Schumach & Thonn.) Engl, Cucurmeropsis mannii
Naudin, Anthocleista spp, Vernonia amygdalina Del and Allium spp. These species were found to
be very important and useful in the treatment of diabetes based on their frequency of occurrence
in the recipes obtained, although only few of the recipes are listed in this work. Most of these
plants are available in the area of study. A need for further scientific research based on the
findings of this work is needed and recommended so that adequate records of indigenous
methods of treating Diabetes mellitus can be kept for posterity, especially in the study area.
Introduction: Phytochemical analysis was conducted on the leaves of Cissus populnea Guill. & Perr., a plant
belonging to the family- Vitaceae/Ampelidaceae. The leaves were collected from New Bussa,
Niger State, Northern Nigeria, air-dried and ground into fine powder. The powdered leaves were
screened and results were properly recorded as observed. Results showed that the saponin
content was the highest with about 47.3%. This is followed by anthraquinones – 33.2% and
flavonoid – 6.48%. Although, results also showed that the cyanogenic glycoside content (3.65%)
is indicative of its poisonous property as the human body may not withstand this large amount at
a time, the small quantity of alkaloid – 2.49% (0.15±0.07mg/g) also suggests that it may be
harmless in some ways. This study, however, supports the fact that leaves of C. populnea contain
important compounds which may be useful in medicine, it also suggests that further research
should be conducted into the plant as a whole, since some of the phytochemicals may be very
dangerous to the human body whether consumed as vegetable or used as medicine.
Introduction: A morphometric study was performed on six Berlinia species of the Nigerian flora. Individual specimens deposited at Forest Herbarium Ibadan and University of Ibadan Herbarium formed the units of study. Twenty morphological characters were assessed and analyzed following conventional taxonomic practice. Results showed a close resemblance between B. craibiana and B. grandiflora, which share affinity with B. bracteosa and B. confusa, while B. coriacea appears to be distantly related. Species distribution studies revealed that B. grandiflora exists in savanna and forest regions while other members of the genus are found only in forest zones. While suggesting practical measures for conserving endangered Nigerian flora, we also recommend that further taxonomic studies be carried out on the genus Berlinia and its related allies to ascertain their placement within the Caesalpiniodeae.
Introduction: This paper empirically examined the potency and value relevance of earnings persistence (EPERS) and its effect on firm performance and the implications of the analysts’ accurate forecast ability from the emerging market of Nigeria.
Introduction: The African continent had witnessed tremendous financial interventions through the assistance of donor agencies towards poverty eradication.
Introduction: This study focuses on the effect of pricing policy on the students’ choice of private universities in Nigeria, focusing on
how the pricing policy influences students’ choice of private universities in Lagos and Ogun States education sector.
The research adopts survey research design using a random sampling Technique. A descriptive statistical tool was
also used in analyzing the data collected with the aid of Statistical Package for social Sciences (SPSS), while Analysis of
Variance (ANOVA) was used in testing the hypotheses. For reliability, the Cronbach alpha was used to test the
reliability of the instrument. The study revealed that there was a significant effect of bundling pricing (BP) on the
students’ choice of private universities. Also, that there was significant effect of penetration pricing (PP) on the
students’ choice of private universities. Furthermore, that there was a significant effect of price skimming (PS) on the
students’ choice of private universities while a significant effect of psychology pricing (PSP) existed on the students’
choice of private universities. The study revealed a significant effect of economy pricing (EP) on the students’ choice
of private universities in Nigeria. The study concluded that pricing policy had a positive and significant effect on the
students’ choice of private universities. The paper recommended that private universities managements should
intensify their effort towards including attractive packages to reduce price, and adopt favorable pricing strategies in
other to influence students’ choice on such private universities.
Introduction: The study examined the effect of earnings quality on book value of quoted companies in Nigeria from 2000 to 2016. A sample of 51 firms was purposively selected for the study out of the population of 173 firms that were listed on the Nigerian Stock Exchange for the period. The study adopted Ex-post facto research design. Data extracted from the published audited financial statements of the firms. Pooled OLS technique was employed in data analysis. The study measured earnings quality with four separate earnings attributes: Accruals quality (AQ), earnings persistence (EPERS), earnings predictability (EPRED), and earnings smoothness (ESMOTH). The study revealed that earnings quality significantly affected book value of the listed firms in Nigeria. Specifically, accruals quality (AQ), earnings persistence (EPERS) and earnings smoothness (ESMOTH) each had a positive effect on book value while earnings predictability (EPRED) had negative effect on book value. By implication, since investors and analysts value high earnings quality, the study suggested that, constancy of earnings and discretionary nature of accruals should be considered, managers should equally ensure information disclosure to enhance quality of earnings and credibility of reported book value.
Introduction: This paper examined the trend and impact of earnings quality on the financial performance of firms from the perspective of accounting information usefulness, aimed at resolving a missing link between current and expected firm performance, due to existing gap between managers and investors on information asymmetry and opportunistic earnings tendencies, in improving managerial and investment decisions and forecast abilities of the analysts towards increasing the level of earning quality and firm performance. The study proposed accounting-based earnings quality measures of accruals quality (AQ), earnings persistence (EPERS), earnings predictability (EPRED) and earnings smoothness (ESMOTH) as proxies to measure earnings quality and Tobin's Q to measure firm financial performance. A sampled of 51 firms listed on the Nigerian Stock Exchange over the period of 2000-2016 were purposively selected. Panel data were extracted from the audited published financial statements. Descriptive and inferential statistics were used for the specified models. The findings revealed that earnings quality proxies jointly had a positive significant effect on the financial performance of the firms. Individual coefficient estimate of each of the variables revealed that AQ, EPRED and ESMOTH each had negative effect on Tobin's Q, while EPERS had a positive significant effect on Tobin's Q. The study recommended that analysts, investors, policy makers and other stakeholders should pay attention to the earnings consistency of time-series behavioral pattern of earnings as measured by predictability and persistence as a guide in managerial and investment decisions andforecasting offuture earnings.
Introduction: This paper examined tax incentive as a catalyst of tax compliance for tax revenue and economic development. It examined the various tax incentives available to tax payers, the level of compliance and its effects on tax revenue and the economic development of Nigeria. An ex-post facto research design was adopted for the study. Data was extracted from Federal Inland Revenues Services (FIRS), Central Bank of Nigeria statistical bulletin. Gross Domestic Product (GDP) was adopted as an indicator of economic development based on the tax revenue as a reflection of tax compliance. The result showed a considerable compliance level based on the tax incentives made available to taxpayers. The study revealed that Tax Revenue (TAXREV) had a positive significant influence on economic development proxy GDP in Nigeria. The paper recommended that government should utilize the tax revenues very effectively, hence there is strong association between tax compliance, tax justice, tax revenue utilization and good corporate governance.
Introduction: This paper examined Tax Base Erosion and Profit Shifting through Transfer Pricing (TBEPTP) evidenced from Nigeria, from the perspective of tax avoidance and from profit shifting manipulative tendencies of multinational companies operations. In this study, we adopted a content analysis research approach where some academic papers, scholarly journals, online research database, and other related materials were reviewed. The study revealed that multinational companies although make a huge tax revenue contribution to Nigeria Gross Domestic Product (GDP), yet in their pursuit of profit maximization goal, engage in tax avoidance strategies inform of profit shifting, through tax havens in manipulating tax motivated transfer pricing, aimed at huge reduction in their tax liabilities. Multinationals globally, engage in exploiting the loop holes in tax policies and laws in their operating jurisdictions, including Nigeria. We recommend that while adequate staffing and quality training is necessary, the Federal Inland Revenue Services (FIRS) in line with Organization for Economic Cooperation and Development (OECD) policy guidelines, take steps to ensure that Base Erosion Profit Shifting Actions (BEPSA) that they consider appropriate be integrated into Nigeria existing tax laws and also should device an acceptable and practicable means of verifying multinational transfer pricing policies and compliance documentation and their head office charges and appropriately deal with capital allowance on assets not wholly attributable to the Nigerian operation towards increasing the nation’s tax revenue base
Introduction: The proliferation of antibiotic-resistant bacteria (ARB) and the prevalence of antibiotic resistance genes (ARGs) in wastewaters are well-established factors that contribute to the reduced potency of antibiotics used in healthcare worldwide. The human health risk associated with the proliferation of ARB and ARGs need to be understood in order to design mitigation measures to combat their dissemination. Using the PCR analysis of genomic DNA, the prevalence of 41 ARGs active against the commonly used six classes of antibiotics was evaluated in 60 bacterial isolates obtained from pharmaceutical wastewaters in Nigeria. The ARGs most frequently detected from the bacterial isolates in each of the antibiotic classes under study include catA1 (58.3%); sulI (31.7%); tet(E) (30%); aac(3)-IV (28.3%); ermC (20%); blaTEM, blaCTX-M, blaNDM-1 at 18.3% each; which encode for resistance to chloramphenicol, sulfonamides, tetracycline, aminoglycoside, macrolide-lincosamide-streptogramin and ?-lactams and penicillins, respectively. Acinetobacter spp., accession number MH396735 expressed the highest number of ARGs of all the bacterial isolates, having at least one gene that encodes for resistance to all the classes of antibiotics in the study. This study highlights wide distribution of ARB and ARGs to the antibiotics tested in the wastewater, making pharmaceutical wastewater reservoirs of ARGs which could potentially be transferred from commensal microorganisms to human pathogens.
Keywords: antibiotic resistance genes (ARGs); antibiotic-resistant bacteria (ARB); pharmaceutical wastewater; tetracycline; aminoglycoside
Introduction: Africa is the second most populous continent and has perennial health challenges. Of the estimated 181 million school aged children in sub-Saharan Africa (SSA), nearly half suffer from ascariasis, trichuriasis, or a combination of these infections. Coupled with these is the problem of tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) infection, which is a leading cause of death in the region. Compared to the effect of the human immunodeficiency virus on the development of TB, the effect of chronic helminth infections is a neglected area of research, yet helminth infections are as ubiquitous as they are varied and may potentially have profound effects upon host immunity, particularly as it relates to TB infection, diagnosis, and vaccination. Protection against active TB is known to require a clearly delineated T-helper type 1 (Th1) response, while helminths induce a strong opposing Th2 and immune-regulatory host response. This Review highlights the potential challenges of helminth–TB co-infection in Africa and the need for further research.
Introduction: Zoonotic transmission of mycobacteria between humans and other animal species is an important aspect of the epidemiology of tuberculosis (TB) in regions of the world where the burden of the disease in humans and other animals is high. This is particularly important in areas in which sociocultural factors increase the possibility for interspecies transmission of different mycobacteria. Carrying out a review of the published literature involving laboratory-confirmed TB cases (by culture) and/or biochemical and molecular identification, we described the presence of Mycobacterium bovis and M. tuberculosis infections in humans and animals from 1975 to 2014. Overall, 1693 isolates of M. tuberculosis complex and other mycobacteria were identified and reported, of which 1131 represented M. tuberculosis, 286 represented M. bovis, 71 represented M. africanum, and 205 represented other mycobacteria. Importantly, 1.3% (15/1131) of the M. tuberculosis isolates reported were identified in cattle, while 8.0% (23/286) of the M. bovis isolates reported were isolated from humans. We suggest that representative sampling of TB cases in both hosts, studied by molecular identification tools, will help significantly in deciphering ongoing transmission between animals and humans in both directions and will enhance TB control in Nigeria.
Introduction: The Mycobacterium tuberculosis complex (MTBC) comprises the species that causes tuberculosis (TB) which affects 10 million people every year. A robust classification of species, lineages, and sub-lineages is important to explore associations with drug resistance, epidemiological patterns or clinical outcomes. We present a rapid and easy-to-follow methodology to classify clinical TB samples into the main MTBC clades. Approaches are based on the identification of lineage and sub-lineage diagnostic SNP using a real-time PCR high resolution melting assay and classic Sanger sequencing from low-concentrated, low quality DNA. Thus, suitable for implementation in middle and low-income countries. Once we validated our molecular procedures, we characterized a total of 491 biological samples from human and cattle hosts, representing countries with different TB burden. Overall, we managed to genotype ~95% of all samples despite coming from unpurified and low-concentrated DNA. Our approach also allowed us to detect zoonotic cases in eight human samples from Nigeria. To conclude, the molecular techniques we have developed, are accurate, discriminative and reproducible. Furthermore, it costs less than other classic typing methods, resulting in an affordable alternative method in TB laboratories.
Introduction: Tuberculosis (TB) remains a public health problem in sub-Saharan Africa coupled with dearth of information about the disease among livestock workers at risk of infection. We determined the prevalence of pulmonary TB infection and risk factors associated with its occurrence among livestock workers in south-western Nigeria.
Introduction: Accurate and timely diagnosis of tuberculosis (TB) is key to effective treatment and management. This study was designed to compare the diagnostic performance of GeneXpert and Ziehl-Neelson (ZN) microscopy test using culture as the reference.
Introduction: Prevalence, molecular epidemiology and risk factors of tuberculosis infection among cattle and livestock workers in Nigeria
Introduction: The molecular biological techniques of polymerase chain reaction (PCR) are accurate and rapid diagnostic methods in the epidemiology of Mycobacterium species in humans and animals, especially in developing countries.In this study, positive cultures from suspected tuberculous lesions of slaughtered cattle from two abattoirs in north-central Nigeria were subjected to a two-step multiplex PCR technique, based on genus typing and genomic regions of difference (RD).Out of 50 suspected tuberculous lesions cultured, 40 isolates were obtained. Based on genus typing, 32 of the isolates were identified as Mycobacterium tuberculosis complex (MTC), one as non-tuberculous Mycobacterium (NTM) and the remaining seven were unclassified. Using genomic RD multiplex PCR, all the 32 isolates initially identified as MTC were further characterized as M. bovis.Our findings show that 80% of positive cultures from suspected tuberculous lesions were identified as M. bovis; hence, re-confirming M. bovis as the main cause of bovine tuberculosis in Nigeria. These results give further credence to the use of PCR-based molecular techniques as excellent complementary epidemiological tools in the tracking of bovine tuberculosis, a zoonotic disease of major public health importance in Nigeria.
Introduction: Carbofuran based pesticides have gained wide usage in Nigeria recently. Consequently, animals and human populations are exposed to them in the environment. Information on in vivo toxicity of carbofuran in experimental models is scanty. The present study therefore examined the hepatotoxicity and clastogenic effects of carbofuran in rats. Male Wistar rats were exposed to carbofuran (p.o) at 0–5 mg/kg bw for 5 weeks. Carbofuran induced significant (p < 0.05) increase in the serum activity of gamma-glutamyltransferase when compared with the negative control, but not activity of serum alanine and aspartate aminotransferases. It also significantly (p < 0.05) induced micronucleated polychromatic erythrocytes formation in the bone marrow as compared with the control. The level of induction is dose dependent in both cases. In addition, there was significant (p < 0.05) higher number of hepatic cells in the cell/mm2 assay for the group treated with carbofuran. Histopathological analysis of liver samples from the treated groups revealed lesions ranging from general congestion (portal, central venous and sinusoidal), mild periportal cellular infiltration, diffused sinusoidal congestion and hepatic necrosis to severe congestion. Findings from this study suggest that carbofuran has clastogenic and hepatotoxic effects in rats. It therefore may constitute an environmental health risks in individuals so exposed.
Introduction: Moringa oleifera is an important multipurpose tropical tree not yet fully investigated for its medicinal and therapeutic
properties which informed the objective for this research work. The M. oleifera n-hexane leaves extract yielded a
solid substance that was re-crystallized several times to obtain a relatively pure compound which was subsequently
derivatized. The FTIR data of the solid substance indicated that the substance is an aliphatic alcohol. Consequently, it
was derivatized to an ester, an aldehyde and a carboxylic acid.
Introduction: The cracked bark of Anacardium occidentale were dried under ambient conditions, chopped into bits and the
ethanolic extract of the cracked bark was obtained by cold extraction. Phytochemical screening was conducted to
identify the types of secondary metabolites present using standard procedures. The profiles of the chemical constituents
present were established using Thin Layer and Column Chromatography methods. Thus, pure chemical constituents
were isolated from the cracked bark of Anacardium occidentale. The isolated compounds were characterized using
FT-IR and their structures determined using data obtained from GC-MS spectrum.
Introduction: Meloidogyne incognita are serious pests of Abelmoschus esculentus cultivation in Nigeria. Generally control has relied on the use of synthetic nematicides, however excessive use of pesticides in controlling them has led to the development of resistance by the organism. Environmental persistence of metabolites has resulted in pollution of surface and underground water. There is need to develop safer pesticides from natural plant metabolites. Extracts of Anacardium occidentale bark were obtained by cold extraction using ethanol. Phytochemical screening was conducted and the unique chemical constituents were identified using Thin Layer and Column Chromatography methods. The results of the phytochemical analysis revealed phyto-constituents like phenols,
Introduction: A scalable production of high surface area nanoporous carbon material (?2994 m2 g?1) with good distribution of micro-, meso- and macro-pores was hydrothermally synthesized using both cheap polymers and graphene foam as carbon sources. The as synthesised material shows a unique interconnected porous graphitic structure. The electrochemical double-layer capacitor fabricated from this nanoporous carbon material exhibited a superior supercapacitive performance of 188 F g?1 at current density 0.5 A g?1. This corresponded to areal capacitance of 6.3 ?F cm?2 coupled with a high energy of 0.56 ?Wh cm?2 (16.71 Wh kg?1) and a power density of 13.39 ?W cm?2 (401 W kg?1) due to extended potential window of 1.6 V in KOH aqueous electrolyte. Moreover, no capacitance loss after 10,000 cycles was observed, owing to the unique structure and large surface area of the active material. The outstanding performance of this material as supercapacitor electrode shows that it has great potential for high performance energy-related applications.
Introduction: A microwave irradiation method has been used to prepare mixed nickel cobalt sulfide (NixCoyS4) nanosheets with different stoichiometric composition as electrodes for electrochemical capacitors. This study has been undertaken to determine the effect of synthesis time and concentration of nickel on the morphology and pseudocapacitance behavior of the NixCoyS4. It was observed that the time had an effect on the morphology of NixCoyS4, producing sheet-like (leaf-like) morphology which curls in flower-like shapes with increase in growth (synthesis) time. The effect of morphology on the electrochemical behavior was studied by cyclic voltammetry (CV), chronopotentiometry (CP) and electrochemical impedance spectroscopy (EIS) techniques in aqueous solutions. The sample with a concentration ratio of 2:1 of nickel and cobalt (NixCoyS4-3) shows higher faradaic performance when compared to other samples grown under similar conditions but with different ratios. The maximum specific capacitance values obtained for was 1110 F g?1 at a scan rate of 5 mV s?1 for this sample. The Coulombic efficiency of the sample was ?80% after 2000 galvanostatic charge-discharge cycles at a current density of 5 A g?1.
Introduction: Half-cell reactions and alkaline direct ethylene glycol and glycerol fuel cells (DEGFC and DGFC) have been studied on Pd-based ternary core–shell (FeCo@Fe@Pd) nanocatalyst using multi-walled carbon nanotubes bearing carboxylic (MWCNT-COOH) and sulfonic acid (MWCNT-SO3H) as supporting platforms. The core–shell–shell nature of this nanocatalyst, obtained via the “microwave-induced top-down nanostructuring and decoration”, was clearly proven from atomic resolution transmission electron microscopy (ARTEM). The functional groups of the MWCNTs show a huge impact on the physico-chemical properties of the FeCo@Fe@Pd nanocatalyst towards the electrocatalytic oxidation of EG and GLY in alkaline media. The FeCo@Fe@Pd on –COOH-treated MWCNTs showed the small particle size of ca. 7.4 nm, uniform loading of the catalyst on the support, large electrochemically-active surface area and enhanced electrocatalytic activity compared to the FeCo@Fe@Pd on –SO3H-bearing MWCNTs. As a preliminary test, FeCo@Fe@Pd/MWCNT-COOH was used for passive, air-breathing anion-exchange membrane based fuel cells (AEM-DEGFC and AEM-DGFC). The analysis of the exhaust products, established using NMR spectroscopy, revealed a high selectivity towards the complete oxidation of both EG and GLY under benign experimental conditions.
Introduction: Electrocatalytic oxidation of alcohols in alkaline solutions is critical for the development of direct alkaline alcohol fuel cells (DAAFCs). This work investigated alcohol oxidation reaction (AOR) at a novel palladium-based core-shell nano catalyst (FeCo@Fe@Pd/C) obtained by the microwave-induced top-down nanostructuring and decoration (MITNAD) synthetic strategy. The electrocatalytic properties of the FeCo@Fe@Pd/C towards the oxidation of ethanol (EtOH), ethylene glycol (EG) and glycerol (Gly) were explored, and compared with those of the Pd/C alone. FeCo@Fe@Pd/C exhibited a remarkable performance in all three alcohols but its best electrocatalytic activity was found in the oxidation of EG where the electrocatalytic rate constant (Kcat) was about 2 times faster than seen in Gly and ? 4 times faster than in EtOH. The excellent performance towards EG was further corroborated by the low resistance to charge transport. Detailed comparison with literature reports shows that the FeCo@Fe@Pd/C is a potentially viable nanocatalyst for use in DAAFC.
Introduction: We have fabricated a symmetric electrochemical capacitor with high energy and power densities based on a composite of graphene foam (GF) with ?80 wt% of manganese oxide (MnO2) deposited by hydrothermal synthesis. Raman spectroscopy and X-ray diffraction measurements showed the presence of nanocrystalline MnO2 on the GF, while scanning and transmission electron microscopies showed needle-like manganese oxide coated and anchored onto the surface of graphene. Electrochemical measurements of the composite electrode gave a specific capacitance of 240 Fg?1 at a current density of 0.1 Ag?1 for symmetric supercapacitors using a two-electrode configuration. A maximum energy density of 8.3 Whkg?1 was obtained, with power density of 20 kWkg?1 and no capacitance loss after 1000 cycles. GF is an excellent support for pseudo-capacitive oxide materials such as MnO2, and the composite electrode provided a high energy density due to a combination of double-layer and redox capacitance mechanisms.
Introduction: A facile method has been utilized to synthesize a hydrophobic form of nano-scaled iron (II) tetrasulfophthalocyanine (nanoFeTSPc), integrated with functionalized multi-walled carbon nanotubes (fMWCNT-nanoFeTSPc). The nanocomposite was characterized by UV–visible spectra, EDX, FESEM, and TEM. The electrocatalytic properties of the film on a glassy carbon electrode were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, chronoamperometry and square wave voltammetry. The fMWCNT-nanoFeTSPc modified electrode demonstrated higher catalytic performance in terms of electron transport and current response compared to the other electrodes studied towards dopamine (DA) detection giving a sensitivity of 0.314 ?A ?M?1 and a limit of detection of 9.86 × 10?8 mol L?1. A selective detection was realized in elimination of ascorbic acid response on the film of fMWCNT-nanoFeTSPc. The detection limit in the presence of a high concentration of ascorbic acid was 3.5 × 10?7 mol L?1.
Introduction: Palladium based nano-alloys are well known for their unique electrocatalytic properties. In this work, a palladium-decorated FeCo@Fe/C core–shell nanocatalyst has been prepared by a new method called microwave-induced top-down nanostructuring and decoration (MITNAD). This simple, yet efficient technique, resulted in the generation of sub-10 nm sized FeCo@Fe@Pd nanocatalysts (mainly 3–5 nm) from a micron-sized (0.21–1.5 ?m) FeCo@Fe/C. The electrocatalytic activities of the core–shell nanocatalysts were explored for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) in alkaline medium. A negative shift of 300 mV in the onset potential for MOR was observed, with a current thrice that of the Pd/C catalysts. A very low resistance to electron transfer (Rct) was observed while the ratio of forward-to-backward oxidation current (If/Ib) was doubled. The overpotential of ORR was significantly reduced with a positive shift of about 250 mV and twice the reduction current density was observed in comparison with Pd/C nanocatalysts with the same mass loading. The kinetic parameters (in terms of the Tafel slope (b) = ?59.7 mV dec?1 (Temkin isotherm) and high exchange current density (jo) = 1.26 × 10?2 mA cm?2) provide insights into the favorable electrocatalytic performance of the catalysts in ORR in alkaline media. Importantly, the core–shell nanocatalyst exhibited excellent resistance to possible methanol cross-over during ORR, which shows excellent promise for application in direct alkaline alcohol fuel cells (DAAFCs).
Introduction: We report a novel microwave-induced fast and efficient synthesis of sub-10 nm sized palladium-decorated FeCo@Fe core–shell nanoparticles (ca. 3–7 nm) from a large-sized FeCo@Fe (0.21–1.5 ?m) precursor, suggesting ‘top-down’ nanosizing. The high electrochemical surface area, tolerance to methanol during oxygen reduction reaction, and the excellent stability of FeCo@Fe@Pd in alkaline electrolytes indicate that this nanomaterial may find future applications in Pd-based catalysis and/or alkaline fuel cells.
Introduction: We report a novel microwave-induced fast and efficient synthesis of sub-10 nm sized palladium-decorated FeCo@Fe core–shell nanoparticles (ca. 3–7 nm) from a large-sized FeCo@Fe (0.21–1.5 ?m) precursor, suggesting ‘top-down’ nanosizing. The high electrochemical surface area, tolerance to methanol during oxygen reduction reaction, and the excellent stability of FeCo@Fe@Pd in alkaline electrolytes indicate that this nanomaterial may find future applications in Pd-based catalysis and/or alkaline fuel cells.
Introduction: Ethnopharmacological relevance
Inflammation processes are implicated in many degenerative diseases. Piper guineense, a West African spice belonging to the Piperaceae family has been reported to contain anti-inflammatory agents.
Introduction: This study aimed to evaluate the effects of ethyl acetate extract of Curcuma longa Linn on the plasma antioxidant status and haematological parameters in alcohol-induced toxicity in female wistar rats. Thirty female wistar rats were divided randomly into six
groups (n = 5). Group I (control) was given normal saline, Group II was administered with 20% ethanol only, Group III was given 100
mg/kg b.w of the extract + 5.22 ml per kg b.w of 20% ethanol, Group IV was given 200 mg/kg b.w of the extract + 5.22 ml per kg b.w
of 20% ethanol, Group V was given 400 mg/kg b.w of the extract + 5.22 ml per kg b.w. of 20% ethanol and Group VI was administered
with 350 mg/kg b.w of Curcuma longa extract orally for 14 days. Plasma antioxidants activities and haematological parameters were
evaluated using standard methods. Ethanol significantly (p < 0.05) decreased the levels of some of the blood parameters (RBC, HB,
WBC, HCT, PLT and PCT) when compared to the control. The pretreatment with Curcuma longa L. significantly (p < 0.05) increased
the levels of RBC, HB, WBC, HCT, LYMP, PLT and PCT) when compared to the group given only ethanol. Oral administration of Curcuma
longa L. significantly decreased the levels of GSH, GPx, MDA, SOD and CAT activities in the plasma as compared to the group administered ethanol only. In conclusion, these observations show that pretreatment with ethyl acetate extract of Curcuma longa Linn exerts
its protective effect on haematological parameters and decreases lipid peroxidation as well as improving plasma antioxidant status.
Introduction: Cnidoscolus aconitifolius (CA) is an edible perennial shrub with promising medicinal properties. We therefore investigated the ameliorative potentials of CA (400 mg/kg) by comparing with ascorbate (400 mg/kg) in dimethylnitrosamine (DMN)-induced clastogenicity and hepatotoxicity. Hepatotoxicity was assessed by determining the levels of reduced glutathione (GSH) and malondialdehyde (MDA), as well as activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase (GGT), catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), and glutathione peroxidase (GPx), while clastogenicity was assessed by scoring the number of bone marrow micronucleated polychromatic erythrocytes (mPCEs). Gas Chromatography Mass Spectrophotometry (GCMS) analysis of the CA extract revealed the presence of phenols, essential fatty acid, carotene, and silicon-rich compounds, and also possesses strong in vitro free radical scavenging potentials comparable to ascorbate. DMN-induced hepatic damage as marked by elevated levels of MDA and GSH, as well as activities of ALT, AST, GGT, and GST were significantly reduced by CA and ascorbate treatments, while the significant reductions in CAT, SOD, and GPx activities as a result of DMN administration were restored following treatments with CA and ascorbate. Also, significant increase in DMN-induced micronuclei formation was significantly reduced following CA and ascorbate treatments. Hepatocyte histopathology revealed severe diffuse centrilobular necrosis and bizarre mitotic figures, which were corrected by CA and ascorbate treatments. Overall, ascorbate demonstrates better effect in vitro, while in in vivo study, CA extracts demonstrates a comparable and better ameliorative effects than ascorbate in the parameters investigated. Therapeutic use of the plant may therefore be a promising focus.
Introduction: Eteng OE, Moses CA, Enobong J, Akamo AJ, Akinloye DI, Ugbaja RN, Akinloye OA. 2020. Protective effects of Curcuma longa rhizomes ethyl acetate extract against alcohol induced oxidative stress and nephrotoxicity in female Wistar rats. Biofarmasi J Nat Prod Biochem 21: 5-12. This study aimed to evaluate the protective effect of Curcuma longa Linn. (syn. Curcuma domestica Val.) rhizomes ethyl acetate extract (CLREAE) facing alcohol-induced oxidative stress and nephrotoxicity. Thirty female (30) Wistar rats were categorized randomly into six groups. Groups 1, 2, 3, 4, 5 and 6 were treated with normal saline; 20% ethanol; 100 mg of CLREAE + 20% ethanol; 200 mg of CLREAE + 20%; 350 mg of CLREAE + 20% ethanol and 350 mg of CLREAE respectively for 14 days. A significant (p<0.05) decrease in the SOD, CAT and GPx activities and GSH concentration of rat treated with only 20% ethanol were found when compared to the normal control group, whereas a significant (P<0.05) increase in the groups pretreated with different doses of the CLREAE were also found when compared to groups with only 20% ethanol treatment. Thus, comparing to the normal control group, treatment with the CLREAE fetched a significant (p<0.05) decrease in the renal biomarkers (creatinine and urea). Whilst, comparing to the groups with 20% methanol treatment, a significant (p<0.05) increase happened in the groups pretreated with different doses of the CLREAE. There was a significant (p<0.05) decrease on Kidney MDA level in rats pretreated with different doses of CLREAE compared with the normal control. It was shown in the results of the histology that there was a physiologic recovery in the kidney tissues as groups were treated with different doses of the CLREAE. Evidenced by reduced necrosis of tubular and glomerular epithelial, the signs of protection against toxicity were found on the rats. The study suggested that through in vivo free radical scavenging ability, the CLREAE has protective effects against alcohol-induced oxidative stress and nephrotoxicity in female Wistar rats.
Introduction: Chlorination is a common method used in domestic water treatment. However, there are concerns
about its safety. This study investigated the probable toxicological effects associated with prolonged oral
administration of sodium hypochlorite (NaOCl), a domestic water disinfectant. Thirty-two male albino rats (180-220g)
were evenly segregated into four groups of eight rats each. Group 1 (control) were orally administered 100 µl
physiological saline, Group 2-4 were orally administered 50 µl, 100 µl and 150 µl/kg body weight of 1.0% NaOCl
respectively bi-daily for 12 weeks. This was followed by the assay for indices of oxidative stress, as well as hepatic
and renal dysfunctions. The results showed significant (p<0.05) dose dependent elevations in activities of catalase,
superoxide dismutase, xanthine oxidase and lactate dehydrogenase, and level of lipid peroxidation. Plasma activities
of aspartate and alanine transaminases as well as urea and creatinine concentrations were significantly increased
(p<0.05) suggesting liver and kidney compromise. The present study suggests that the use of NaOCl in treating water
domestically may present with subtle deleterious biochemical effects.
Introduction: Trichloromethane (TCM) serves as an ingredient in pesticide formulations and fire extinguishers. It is a reported hepato- and renal-toxin. We therefore investigated the chemo-preventive effect of diallyl disulfide (DADS) on TCM-induced hepatotoxicity. Twenty five rats, divided into five groups of five animals each were used. TCM at the dose of 200?mg/kg was orally administered, and concomitantly treated with DADS (50?mg/kg), 5 days per week for 3 weeks. Compared with control, there was a significant increase in hepatic expressions of nuclear factor kappa B (NFkB), TUNEL positive cells (apoptosis), and concentrations of malondialdehyde (MDA), hydrogen peroxide (H2O2), and nitric oxide (NO). Also, a significant decrease in expressions of p53, and activities of catalase (CAT) and glutathione peroxidase (GPx), as well as level of reduced glutathione (GSH) was recorded following TCM administration. Following treatment, DADS intervention significantly reduced the hepatic NFkB expressions, apoptotic positive cells as well as levels of MDA, H2O2, and NO, and also significantly increased the level of GSH, activities of CAT and GPx compared with TCM group, while its effect on expressions of p53 was insignificant. Hepato-protection by DADS against TCM-induced hepatotoxicity may therefore be via suppressions of NFkB activation, apoptosis, and oxidative stress in rats.
Introduction: Exposure to pesticides, especially cypermethrin (Cyp) which is one of the most widely used synthetic pyrethroids, has been associated with decline in semen quality and increased risk of male infertility. This study was targeted at investigating the possible ameliorative role of the methanolic extract of Jatropha gossypifolia (JG) leaves and alpha-lipoic acid against testicular/spermatozoal aberrations induced by cypermethrin exposure in rats. Eight groups of seven male wistar rats each were treated orally for 28 days: control, 20 mg/kg body weight (b.wt) of Cyp, Cyp+JG(50 mg/kg b.wt), Cyp+JG(100 mg/kg b.wt), Cyp+?-LA(50 mg/kg b.wt), JG(50 mg/kg b.wt), JG(100 mg/kg b.wt) and ?-LA(50 mg/kg b.wt). Results from this study showed that cypermethrin exposure significantly decreased the livability of spermatozoans (15.09%) and increased the percentage of spermatozoans with morphological aberrations (153.40%). The plasma fructose concentration was also significantly reduced (80.89%) by the administration of cypermethrin. The testicular antioxidant status was also significantly altered after cypermethrin exposure. In addition, there was a significant increase in the lipid profile (triglycerides, 96.46%; cholesterol, 64.99%; and phospholipids, 132.94%) of the testes after cypermethrin administration when compared to control. Co-administration with the doses of the methanolic leaf extract of the Jatropha gossypifolia significantly reversed these alterations. With further studies, Jatropha gossypifolia plant could be a possible remedy for the treatment of reproductive dysfunctions.
Introduction: Most rivers in Nigeria are polluted without conscious efforts to abate ensuant consequences. Thus, Clarias gariepinus, an aquatic commercial food from Ogun River, Nigeria, was studied to investigate the impact of pollution on antioxidants and proximate composition. During the rainy season, 50 C. gariepinus (average weight 426.53 ± 24.40g and length 37.73 ± 0.95cm) were site sampled, 10 from each of Ago-Odo, Ago-Ika, Oke-Sokori, and Quarry along Ogun River course. Ajegunle-Adao cultured pond, served as control. The parameters assayed for included: some heavy metals and physico-chemical properties of sampled water, antioxidants and proximate composition of the fish samples. Physicochemical parameters of river studied showed that temperature of all sites ranged from 26 to 29°C, pH: 6.9 to 7.8, dissolved oxygen: 9.5 to 21.6, biochemical oxygen demand: 3.60 to 14.10, and chemical oxygen demand: 60 to 650. Lead (Pb) concentration ranged from 4.0 to 17.0 ?g/L and cadmium (Cd): 0.0 to 6.0 ?g/L. Blood Pb, Cd, activities of: superoxide dismutase, catalase, glutathione-S-transferase, plasma xanthine oxidase, and lipid peroxidation level of fish samples from Ago-Ika were most significantly (p < 0.05) high, with significant (p < 0.05) lowest reduced glutathione concentration amongst the samples from polluted sites when compared to control fish. Proximate analysis showed that the fish samples from Ogun River had significantly (p < 0.05) lower protein, fat contents, and higher nitrogen-free extract while Ago-Ika, Oke-Sokori and Quarry sites had significantly (p < 0.05) lower moisture, ash and fibre contents when compared with control. It can be concluded that the impact of pollution induced oxidative stress and significantly diminished the nutritional value of C. gariepinus from Ogun River.
Introduction: This study evaluates the hepatoprotective effects of hydroethanolic extract of (defatted) Buchholzia coriacea seed (HEBCS) against lipopolysaccharide (LPS) induced inflammatory liver injury in the rat.
Introduction: This investigation estimated the anti-oxidative potential of Aloe Barbadensis gel extracts in rats against alcohol-induced oxidative stress.
Introduction: Cypermethrin (Cyp), a synthetic pyrethroid developed for agricultural and public health applications, has become harmful to the environment and mammalian life owing to indiscriminate use.
Introduction: In this investigation eggshell (ES), a waste material was prepared as substitute in the place of the commonly used carbon black (CB). Three different samples of Natural rubber (NR) were prepared through chemical modification via deproteinization, depolymerization and epoxidation. Deproteinized Natural Rubber (DeNR) was produced by reaction with urea and sodium dodecylsulphate (SDS); Depolymerized Natural Rubber (DNR) was produced by depolymerization of natural rubber latex using nitrobenzene and Epoxidized Natural Rubber (ENR) was produced by reaction with performic acid. The NR, DeNR, DNR and ENR composites filled with carbon black and eggshell at three ratios of 100/0, 50/50 and 0/100 were prepared and labeled as mixes A to C. The physico-mechanical properties, swelling, and solubility parameters of solvents into the different vucanizates were studied. The values for the tensile strength, modulus @ 500, elongation, hardness and abrasion increased with the addition of the eggshell into the modified NR composites with values higher than the standard (NR with CB). However, the compression set of the NRCB vulcanizates was better than the vulcanizates of modified NR with the 100% eggshell. The vulcanizates with ES also showed less swelling rate in all the solvents used. Keywords: Deproteinize natural rubber, Depolymerized Natural rubber, Epoxidized natural rubber, Eggshell waste, Properties, swelling.
Introduction: Unhealthy dietary patterns are associated with metabolic changes and increased risk of non-communicable diseases (NCDs), but these associations have not been investigated in representative populations of university undergraduates in low-to-middle income countries (LMICs).
Introduction: The present study was designed to investigate aluminium phosphide (ALP)-induced testicular toxicity, including its effects on sperm parameters and histological alterations in Wistar rats, and the possible protective role of hesperidin (HSD). Oral administration of ALP at 1.15 mg/kg body weight (1/10 LD50) for 30 days resulted in a significant increase in testicular malondialdehyde, lipid hydroperoxides, and oxidized protein levels. These indicators of oxidative stress were accompanied by decreased activity of the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, followed by a drastic reduction in the non-enzymatic antioxidant indices of glutathione and total antioxidant capacity when compared to control. Furthermore, ALP treatment produced a marked reduction in sperm count, motility and viability while increasing abnormal sperm morphology and adverse histopathological changes in testis. Co-administration with HSD significantly ameliorated ALP-induced testicular damage by suppressing oxidative stress indices and enhancing antioxidant status while also improving the sperm parameters and histological alterations in ALP-treated rats. The results of the present study indicated that testicular toxic effects of ALP are due to oxidative imbalance and that HSD could be a potential therapeutic agent against ALP-induced testicular damage.
Introduction: Jatropha gossypifolia has been associated with diverse medicinal characteristics. This study was aimed at
investigating the hemato-protective ability of the methanolic extract of Jatropha gossypifolia leaf (JG) and alphalipoic acid (ALA) on cypermethrin-induced hematotoxicity; and to investigate the possible hematotoxic effect of
the plant extract on the rats. The animals were grouped into eight groups of seven rats each and were administered
as follows: Group I (control), corn oil; Group II, cypermethrin (CYP) (20mg/kg); Group III, CYP + (JG50mg/kg);
Group IV, CYP + JG100mg/kg; Group V, CYP + ALA50mg/kg; Group VI, JG50mg/kg; Group VII, JG100mg/kg;
and Group VIII, ALA50mg/kg. Data from this study showed that cypermethrin significantly (P<0.05) increased
the amount of the red blood cells (RBC), white blood cells (WBC), lymphocytes (LYMP) and significantly (P<0.05)
decreased the concentrations of the mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin
concentration (MCHC) and mean corpuscular volume (MCV) when compared to control. It also caused a nonsignificant (P>0.05) increase in hematocrit (HCT), haemoglobin (HG), granulocytes (GRAN) and platelets when
compared to the control. Co-administration with the different doses of the methanolic extract of Jatropha
gossypifolia and ALA were able to reverse these alterations. Thus, we concluded that the methanolic extract of
Jatropha gossypifolia at the doses considered are safe and will elicit hemato-protective effect on cypermethrininduced hematotoxicity.
Introduction: Dyslipidemia is a common metabolic disorder especially in diabetes mellitus (DM). In this study, the ability of Sapium ellipticum (SE) leaf extract to restore lipid homeostasis in streptozotocin-induced diabetes was examined. DM was induced in experimental rats (Wistar strains) using single intraperitoneal dose (55?mg/kg body weight ) of streptozotocin (STZ). Treatment of diabetic rats with SE was oral (p.o), at doses of 400 and 800?mg?kg?1 BW, twice daily at 8?h interval for 21 days. Lipid parameters were analyzed in the serum of rats using test kits. SE caused a significant () reduction in STZ-induced hypercholesterolemia in a dose dependent pattern (13.7 and 17.89%). These effects were comparable to that provided by metformin (15.45%), a standard antidiabetic drug. Similar pattern was noted with serum triglycerides (TG) (10.63 and 19.06%) and LDL (31.47 and 25.97%). Adipose tissue TG level was improved to near normal. Besides, the cardiovascular risk predictors in terms of atherogenic index of plasma (AIP) and LDL/HDL ratio were lowered by 57.85 and 44.12%, respectively. However, the extract failed to significantly reverse the STZ-induced decline in serum HDL. Overall, with AIP value of 0.28 and LDL/HDL ratio of 0.91, SE demonstrated the potential to maintain lipid homeostasis in the diabetics.
Introduction: Due to their potential and medicinal
values, herbal medicine has employed the use of
plants for therapeutic purposes based on the
chemical compounds found in them. The major
components are organic compounds, with biological
activity, but none of them act efficiently and
effectively alone with crude fractions possessing a
better efficacy and exhibiting synergetic effects.
Jatropha gossypifolia has been traditionally used for
its anti-inflammatory, analgesic, hepatoprotective,
antimicrobial, antioxidant, strong wound healing
and hypoglycemic properties. This work was carried
out to determine the phytochemical and nutritional
status of Jatropha gossypifolia leaves powder. This
present work employed the use of High Performance
Liquid Chromatography (HPLC) to further
quantitatively elucidates the various sub-fractions of
the phytochemicals earlier reported by other
researchers. Results showed the presence of vitamins
B1 (6.29mg), B2 (10.96mg), B3 (3.65mg), B5
(4.99mg), B9 (4.03x10-1mg), C (172.38mg), A
(4.71x10-2mg), E (56.23mg) and K (26.50mg) in
100g of the plant material. Cobalt, Manganese, Zinc,
Lead, Calcium, Magnesium, Potassium, Sodium,
Phosphorus, Selenium, flavonoids, tannins, phenolic
acids, sterols, carotenoids, alkaloids, saponins, and
glycosides are also present in different
concentrations. Proximate analysis showed that the
plant material contained nutrients such as crude fat
(6.36%), crude protein (14.80%), carbohydrate
(34.18%), Ash (9.38%), crude fiber (10.31%),
moisture content (24.97%) and had caloric value of
(253.16 kcal). These substances may be responsible
for the health related properties of the plant and the
traditional use in the south-western part of Nigeria.
Introduction: To examine the effects of Sapium ellipticum (SE) leaf extract on the hepatic activities of glucokinase and glucose-6-phosphatase in streptozotocin-induced diabetic Wistar rats.
Introduction: Lead toxicity resulting from occupational or environmental exposure has long been treated with chelating agents and/or antioxidants. The ameliorative effects of these chelators on the genotoxicity of lead and possible damage on the DNA are yet to be fully investigated. In this study, the efficacy of conventional chelators (namely; 2, 3-mesodimecarptosuccinic acid (DMSA), D-Penicillamine and Calcium disodium ethylene di amine tetra acetate (CaNa2EDTA) with vitamin C were compared in the tissues of experimental rats exposed to lead. Twenty four hours after the last treatment, animals were sacrificed under anaesthesia, the brain and the liver of the animals were then harvested, mopped dry and stored on ice. Quantitative DNA fragmentation was determined spectrophotometrically using the diphenylamine reaction. Result showed a 4-fold increase in the percentage damage observed in the brain of animals administered lead for 12 weeks, with a 2-fold increase observed in the liver over the control group. Treatment with Vitamin c and CaNa2EDTA for 5 days and 10 days significantly reduced the fragmentation percentage in the liver. While CaNa2EDTA seem to have no significant ameliorative effect in the brain tissue. Treatment with D-Penicillamine also showed significant ameliorative effect in both tissues. Ten days treatment with succimer however proved more effective than the 5 days treatment. The results of this experiment did suggest a gradual reversal in oxidative DNA damage following withdrawal from exposure and the most effective treatment observed with vitamin c in both tissues.
Introduction: Nitric oxide is a biological messenger molecule that plays important roles in controlling neurotransmitter release, neurodevelopment, memory function, and regulation of gene expression. In this study, the time course effects of varying dose of Cannabis extract on nitric oxide in the brain and plasma was investigated. Twenty four hours after the last treatment, animals were sacrificed under anaesthesia, the brain of the animals were harvested, mopped dry and stored on ice. Nitric oxide activity was assayed according to Griess reaction assay. In the plasma, the results shows that at 4 weeks, there was a significant increase (p < 0.05) in the concentration of nitric oxide in all doses with compared with control. 25 mg/kg dose has a higher concentration compared with 12.5 mg/kg and 50 mg/kg body weight dose. However, at 8 weeks, there was a decrease in concentration of nitric oxide in all the doses compared to 4 weeks, but when compared with the control group, only 12 mg/kg dose significantly decreased. In the brain however, 12.5 mg/kg dose shows no significant difference in NO concentration through the duration of exposure compared to the control group. However, 25 mg/Kg and 50 mg/Kg body weight dose of Cannabis significantly decrease NO concentration in the brain of rat. The results suggest that at high doses, NO is reduced in the brain and at low dose its increased. The decrease in NO concentration may affect the regulatory function of NO in the brain as nitric oxide affect serotonergic transmission which could explain the imopaired cognitive function in chronic Cannabis users.
Introduction: Diabetes mellitus continues to exist as one of the world’s commonest chronic diseases, and the incidence of diabetes is presumed to grow steadily. With the associated adverse side effects of some of the current drugs, the management of diabetes mellitus continues to pose serious challenge in the medical field. There is a need for more robust approach to the treatment and management of diabetes and plants with their anti-diabetic potentials are expected to play key roles in the discovery of new and more potent pharmaceuticals that can successfully treat diabetes. Costus afer, a reported anti-diabetic plant was investigated in the present study for its anti-diabetic properties against certain therapeutic target of diabetes. Phytochemical constituents of C. afer were obtained through GC-MS analysis. These phytochemicals were docked into the binding pocket of the therapeutic targets (glycogen phosphorylase, pancreatic alpha-amylase, dipeptidyl peptidase IV (DPPIV), aldose reductase). The docking scores from Autodock vina were validated and the correlation coefficient (R2) graph of the docking scores of ChemBL’s 125 compounds, docked into the human aldose reductase binding pocket against their corresponding pIC50 values gives R2=0.86, while the correlation coefficient graph of the docking scores of 50 compounds from ChemBL, docked into Dipeptidyl peptidase IV binding pocket against their corresponding pIC50 values gives R2=0.92. In the present study, the phytochemical Citronellyl isobutyrate with a binding affinity of -9.1 kcal/mol has the best inhibitory effect on the aldose reductase receptor/enzyme. The drug likeness of Citronellyl isobutyrate being the lead compound was determined through the calculation of its molecular properties. Citronellyl isobutyrate is a promising therapeutic agent in the treatment of type II diabetes and its associated complications.
Introduction: There is a global increase in the prevalence of metabolic syndrome (MetS) with relative paucity of data on the burden of this syndrome in developing countries like Nigeria. This study evaluated the prevalence of MetS among apparently healthy subjects in Nigeria.
Introduction: Edible camphor (EC) is one of the ingredients in the preparation of local
infusion for the management and treatment of pile, back pain, and erectile dysfunction,
which are practices commonly in the south-western part of Nigeria. Conversely, 2 and 4
g/kg EC significantly increased the serum level of FT3 but was significantly reduced by 6
g/kg EC, and finally, EC administrations did not have any significant effect on serum PSA
Introduction: The growing burden of hypertension and type 2 diabetes mellitus (T2DM) in Nigeria and
related cardiovascular complications is becoming a public health concern. Cardiovascular risk
factors were evaluated in control subjects (n=150) and patients (n=470) [hypertensive nondiabetics (n=179), normotensive diabetics (n=132), hypertensive diabetics (n=159)]
attending at the Medical Out-Patient Clinic of the State Hospital, Abeokuta, Nigeria.
Cholesterol, triacylglycerols and phospholipids were determined spectrophotometrically in
plasma, erythrocytes and lipoproteins. The presence of either or both diseases resulted in
significant (p<0.05) perturbations in blood lipids of the male and female patients.
Dyslipidemia was characterised by increased concentrations of cholesterol and triacylglycerols
in plasma, erythrocytes, low density lipoprotein (LDL) and very low-density lipoprotein
(VLDL). The increase was more pronounced in hypertensive diabetics. High density
lipoprotein (HDL) cholesterol values of the male and female patients were between 35% to
43% and 37% to 43% respectively lower than their control counterparts, while that of HDL
triacylglycerols was between 8% to 10% and 6% to 23% respectively lower than their control
counterparts. Plasma and erythrocyte phospholipid content increased significantly (p<0.05) in
all the patients when compared with their control counterparts except in the erythrocytes of the
normotensive diabetic male, where significant decrease was observed. Our findings suggest
that enhanced hypercholesterolemia, hypertriacylglycerolemia and hyperphospholipidemia in
plasma and erythrocytes may be responsible for increased cardiovascular complications in the
comorbidity since the combined dyslipidemia are more pronounced in comorbidity of
hypertension and T2DM than when either of the two conditions occurs in isolation.
Introduction: Increase in plasma free fatty acids (FFAs) concentrations may cause cellular damage via the induction of oxidative stress. The aim of this present study was to investigate FFAs and oxidative stress in hypertension co-morbidly occurring with Type 2 Diabetes Mellitus (T2DM). Age and sex matched control subjects (n=150) and patients (n=470) [hypertensive nondiabetics (HND, n=179), normotensive diabetics (ND, n=132), hypertensive diabetics (HD, n=159)] presenting at the Medical Out-Patient Clinic of the State Hospital, Abeokuta, Nigeria were recruited. Fasting plasma glucose, creatinine, urea, FFAs, thiobarbituric acid reactive substances (TBARS) were determined spectrophotometrically. The presence of either or both diseases resulted in significant increase (p<0.05) in the plasma FFAs and oxidative stress marker-TBARS in different compartments (plasma, erythrocytes andlipoproteins) for both male and female patients when compared with their control counterparts. The increase in FFAs was more marked in comorbidity female when compared with other female patients. There was significant (p<0.05) difference in gender FFAs concentrations. In both controls and patients, FFAs in plasma are significantly (p<0.05) higher in male when compared with their female counterparts. This research revealed biochemical variations in hypertension co-morbidly occurring with T2DMcharacterised by gender-related elevation in FFAs and enhanced oxidative stress. Plasma FFAs might be a good biomarker predicting the occurrence and development of hypertension and/or T2DM.
Introduction: 5-Fluorouracil (5-FU) is a pyrimidine analogue that is used as an anti-cancer drug but its therapeutic potential is limited by its hepatotoxicity. This study therefore, aimed at investigating the protective effect of crocin, a natural supplement, against 5-FU-induced liver injury. Male rats were administered with 5-FU (30 mg/kg b.wt i.p.) for 5 days. Two groups of animals were either orally treated 3 days prior to or 3 days after 5-FU administration with crocin (40 mg/kg bwt). Another group was concurrently treated with crocin along with 5-FU administration. Biochemical variables indicative of liver injury, oxidative stress and liver histopathological alterations were thereafter determined. 5-FU administration markedly increased oxidative stress and markers of hepatic injury. Pre-, concurrent and post-treatment with crocin significantly reduced MDA, AOPP and LOOH levels and increased total antioxidant capacity compared to the 5-FU alone group, with improvement in the activities of the antioxidant enzymes, SOD, CAT and PONase. Liver injury was markedly reversed when AST, ALT and ALP activities estimated in the three treatment groups were compared to 5-FU group, but the restoration was incomplete, compared to the control. These biochemical variables were supported by histopathological examinations. The results indicate that crocin supplementation can ameliorate 5-FU-induced oxidative stress and liver injury in rat.
Introduction: Highlights
•
DMN administration significantly decreased serum total cholesterol, testosterone (TST), luteinizing hormone (LH), free triiodothyronine (fT3), and kallikrein III (KLK-3) levels.
•
Pre-treatment with ascorbate significantly increases LH and KLK-3 levels.
•
Ascorbate post-treatment and pre-treatment significantly increased fT3 and decreased TSH levels respectively.
Introduction: This study investigated the inhibitory effects of Sapium ellipticum (SE) (Hochst) Pax leaf extract on some carbohydrate metabolizing enzymes, pancreatic ?-amylase and intestinal ?-glucosidase activities in vitro. The inhibitory potential of SE extract was measured against Quercetin. SE extract in a dose dependent pattern significantly inhibited the activity of pancreatic ?-amylase by 67.2% at 10 mg/mL. This effect was comparable to that of quercetin which offered 82.6% ?-amylase inhibition. In terms of intestinal ?-glucosidase activity, the inhibitory effect of the extract was significantly lower than that of quercetin at all investigated concentrations. At 10 mg mL?1 (maximum tested concentration), SE extract exhibited 35.8% inhibitory activity on ?-intestinal glucosidase compared to the 74.3% exhibited by Quercetin at the same concentration. Phytochemical analysis results showed that SE contained 74 ± 3.12 milligram Gallic acid equivalents of total phenols and 67.2 ± 2.04 milligram Quercetin equivalents of flavonoids per gram of extract. Fourier Transformed Infra red spectroscopy (FT-IR) of SE extract revealed the presence of active functional groups reminiscence of polyphenols. Alpha amylase and ?-glucosidase activities (in vivo) greatly contribute to postprandial hyperglycemia which is a great risk factor for type 2 diabetes mellitus. The inhibitory potential of SE extract on these enzymes as observed in this study suggests a positive and probable role of the extract in the management and treatment of diabetes mellitus, particularly, type 2.
Introduction: Arsenic poisoning is a major environmental event affecting millions worldwide and its treatment with chelating agents has
met with limited success. While arsenic toxicity affects multiple systems in the human body, its mode of action has not
been fully elucidated. The present study therefore, investigated the possible protective effects of catechin against
hepatorenal damage and dyslipidemia induced by arsenic exposure. Rats were exposed to arsenic (100 ppm) through their
drinking water and were treated with catechin (40 mg/kg and 80 mg/kg, body weight) for 30 days. Arsenic exposure
resulted in liver dysfunction obvious with increased activities of the hepatic enzymes alanine aminotransferase (ALT),
alkaline phosphatase (ALP) and aspartate aminotransferase (AST). This was accompanied with significant elevation of
kidney function markers urea and creatinine (p < 0.05). Furthermore, arsenic caused the distortion of lipid metabolism
resulting in hypercholesterolemia, hypertriglyceridemia and increased plasma phospholipid in the animals. Co-treatment
with catechin effectively protected against arsenic-mediated hepatotoxicity, prevented renal damage and restored lipid
homeostasis in the rats. The present data indicate the ability of catechin to potentially prevent arsenic-induced nephrohepatotoxicity and dyslipidemia in rats
Introduction: Arsenic and di-(2-ethylhexyl) phthalate (DEHP) are environmentally ubiquitous and epidemiologically important toxic agents that millions of people are currently exposed to, worldwide. Although the adverse impact due to exposure to either arsenic or DEHP are documented, the toxicological effects of co-exposure to these agents are largely unknown. In this study, exposure to these chemicals was investigated for their effects on ATPase activities in the brain, liver and kidney of rats. Male Wistar rats were exposed daily to 100 mg L-1 arsenic via drinking water and to 100 mg DEHP kg-1 body weight in corn oil either individually or concurrently for 30 days. Toxicity was assessed by evaluating changes in body and organ weights, as well as, Na+/K+-, Ca2+-, Mg2+- and total ATPase activities in the brain, liver and kidney. Exposure to either arsenic or DEHP resulted in drastic reduction in activities of the enzymes in the compartments investigated, except in the brain where Na+/K+- and Mg2+- ATPases had their activities significantly increased. Also, DEHP displayed no effect on the total ATPase and Ca2+ ATPase in the kidney and brain, respectively. Interestingly, co-exposure to these toxicants significantly stimulated the activities of all these enzymes in the brain. In this compartment, combined treatment resulted in an additive interaction between the toxicants and a potentiation effect of arsenic on DEHP with regards to the Na+/K+- ATPase activity and Ca2+- ATPase activity, respectively. Our findings demonstrate tissue specific response to combined arsenic and DEHP exposure in rats with the effect on the brain significantly different from other compartments.
Introduction: This paper presents concepts of Bernoulli distribution, and how it can be used as an approximation of Binomial, Poisson and Gaussian distributions with different approach from earlier existing literatures. Due to discrete nature of the random variable X, a more appropriate method of Principle of Mathematical Induction (PMI) is used as an alternative approach to limiting behavior of binomial random variable. The study proved de'Moivres Laplace theorem (convergence of binomial distribution to Gaussian distribution) to all values of p such that p p ? 0 and p ? 1 using a direct approach which opposes the popular and most widely used indirect method of moment generating function.
Introduction: The purpose of this work is to introduce a new iteration called the modified Picard-S-AK hybrid iterative scheme for approximating fixed point for Banach contractive maps. We show that our scheme converges to a unique fixed point p at a rate faster than the recent AK iterative scheme for Banach contractive maps. Furthermore, using Java programming language, we give some numerical examples to justify our claim. Stability and data dependence of the proposed scheme are also explored.
Introduction: Turbo codes play an important role in making communications systems more efficient and reliable. This paper provides a description of two turbo codes algorithms. Soft-output Viterbi algorithm and logarithmic-maximum a posteriori turbo decoding algorithms are the two candidates for decoding turbo codes. Soft-input soft-output (SISO) turbo decoder based on soft-output Viterbi algorithm (SOVA) and the logarithmic versions of the MAP algorithm, namely, Log-MAP decoding algorithm. The bit error rate (BER) performances of these algorithms are compared. Simulation results are provided for bit error rate performance using constraint lengths of K=3, over AWGN channel, show improvements of 0.4 dB for log-MAP over SOVA at BER 10 -4
Introduction: In this paper we describe a simulation study of the impact of vehicular traffic on the performance of cellular wireless network at microwave carrier frequencies above 3 GHz and up to 15 GHz, where the first and subsequent tiers co-channel interfering cells are active. The uplink information capacity of the cellular wireless network is used for the performance analysis. The simulation results show that vehicular traffic causes a decrease in the information apacity of a cellular wireless network. Results also show that for both light and heavy vehicular traffic environment, the nclusion of subsequent tier co-channel interferences caused a decrease of between 3 - 12% in the information capacity of the cellular wireless network as compared to the case, when only the first tier co-channel interferences are active.
Introduction: This paper presents an adaptive multiuser receivers scheme for MIMO OFDM over Turbo-Equalization for Single-Carrier Transmission. It involves the joint adaptive minimum mean square error multiuser detection and decoding algorithm with prior information of the channel and interference cancelation in the spatial domain. A partially filtered gradient LMS (Adaptive) algorithm is also applied to improve the convergence speed and tracking ability of the adaptive detectors with slight increase in complexity. The proposed technique is analyzed in a slow and fast Rayleigh fading channels in MIMO OFDM systems. The adaptive multiuser detection for MIMO OFDM (AMUD MIMO OFDM) perform as well as the iterative equalization for single-carrier.
Introduction: In this paper, mathematical analysis, supported by simulations is used to study the impact of base station antenna height on the performance of land mobile cellular network. The performance is evaluated in terms of the uplink information capacity of the cellular wireless network, when both the first six co-channel interfering cells (first tier) and those beyond it are considered to be dominant. It is shown that at microwave frequencies beyond 2 GHZ as the antenna height increases the area spectrum efficiency of the land mobile cellular network decreases.
Introduction: A number of reduced-complexity methods for turbo equalization have recently been introduced in which MAP equalization is replaced with sub optimal, low complexity approaches. In this paper, we investigate the inefficiency of the conventional decision feedback algorithm when higher-level modulation is used in Inter Symbol Interference channels. We estimates the data using the apriori information from the SISO channel decoder and also the a priori detected data from previous iteration to minimize error propagation. The proposed algorithm for 8-phase shift keying, 16-phase shift keying and 64 quadrature amplitude modulation was verified by assuming a statistical model for the a priori information combined with equalizer output to improve the interference cancellation. The simulation results show that the proposed low complexity DFE algorithm improves considerable compared to the conventional DFE when higher-level modulation are used. It was shown that at higher level modulation, the modified DEF has 1.6dB gain over the conventional DEF after seven iterations.
Introduction: A number of reduced-complexity methods for turbo equalization have recently been introduced in which MAP equalization is replaced with sub optimal, low complexity approaches. In this paper, we investigate the inefficiency of the conventional decision feedback algorithm when higher-level modulation is used in Inter Symbol Interference channels. We estimates the data using the apriori information from the SISO channel decoder and also the a priori detected data from previous iteration to minimize error propagation. The proposed algorithm for 8-phase shift keying, 16-phase shift keying and 64 quadrature amplitude modulation was verified by assuming a statistical model for the a priori information combined with equalizer output to improve the interference cancellation. The simulation results show that the proposed low complexity DFE algorithm improves considerable compared to the conventional DFE when higher-level modulation are used. It was shown that at higher level modulation, the modified DEF has 1.6dB gain over the conventional DEF after seven iterations.
Introduction: Reducing Impulse noise is a very active research area in communication systems. This paper presents a digital smear-desmear technique (SDT) applied to data transmission over band limited channels. A generalized set of filter design criteria based on minimizing the average bit error probability is introduced. The design criteria were applied to a practical digital filter implementing SDT techniques. The SDT is simulated and combined with coded communication systems for high data transmission rate. Simulation results show that the SDT yields a significant improvement in bit error rates for coded systems subject to impulse noise, relative to the systems with no SDT. The technique also completely removes the error floor caused by the impulse noise.
Introduction: The MMSE-DFE is a well established Intersymbol Interference (ISI) mitigating structure on linear, noisy, and dispersive channels. Time invariant communication channels exhibits ISI for severe frequency-selective channels. In this paper we investigate the iterative decoding with imperfect MMSE decision feedback equalizer using different modulation scheme. We assume that soft outputs from channel decoder are independent identically distributed Gaussian random variables with known mean and variance. The Imperfect MMSE DFE using different modulation outperforms other turbo equalization algorithms of similar computational complexity in terms of bit-error rate. The achieved improvement is up to 3dB for severe frequency-selective channels.
Introduction: The paper describes a digital smear-desmear technique (SDT) based on polyphase sequences with good autocorrelation properties. These sequences are applied to the design of digital smear/desmear filters and combined with Trellis-coded modulation (TCM) codes. The scheme has been investigated for 16-QAM and 64-QAM modulation. The impulse noise is modeled as a sequence of Poisson arriving delta functions with gaussian amplitudes. The impulse noise parameters are computed from experimental data. Results shows that the SDT filter design method yields a significant improvement in bit error rates as when subject to impulse noise, relative to systems with no SDT.
Introduction: Inter symbol interference (ISI) constitutes a major impediment to reliable communications in multipath channels. We proposed a low complexity soft feedback Interference canceller (SFEIC) that combines the equalizer outputs and a priori information to form more reliable estimates and perform successive interference cancellation. The receiver performs soft output decisions, achieved by a soft-input soft-output (SISO) detector and a SISO channel decoders, through an iterative process. Simulation results are presented showing that the proposed SFEIC BER perform well compared with MAP equalizer and outperform the conventional MMSE decision feedback equalizer. The results are presented for rate ½ turbo codes with Quadrature-phase shift keying (QPSK) modulation, transmitted over inter symbol interference (ISI) channel having severe frequency distortion. The performance is about 0.8dB gain over MMSE DFE equalizer at bit-error rate of 10 -5 .
Introduction: In this paper a prefiltering method is considered where an all pass filter is employed at the receiver before equalization to create a minimum phase overall impulse response. In the presence of ISI, the all pass filter concentrates the maximum symbol energy in the correct sampling instances and subsequently cancel the non causal precursor ISI by replacing the samples and channel by their minimum phase equivalent. The system performance attainable with the proposed equalization is determined for transmission with channel coding. The use of all pass filtering is beneficial to the performance of a communication receiver that operates in a dispersive multipath propagation environment and thereby improves capacity. Simulation results are given, which demonstrate that the proposed approach outperform the conventional decision feedback equalizer.
Introduction: There has been a demand for high data rate for wireless communication system devices, mainly mobile multimedia applications. This paper investigates the suitability of Turbo Equalization as a means of achieving low bit error rate in the future high data communication systems. Turbo equalization is an approach to coded data transmission over channels with Inter-symbol interference (ISI) which can yield additional improvement in bit error rate. The paper demonstrates that at higher modulation scheme using iterative equalization method, high date rate can be achieved. The performance evaluation shows that turbo equalization is beneficial for higher modulation and thereby increase data rate with a reasonable complexity.
Introduction: We propose a system for wireless video multicast/broadcast to mobile handheld devices. We exploit the latest achievements in video coding (scalable 3D wavelet-based video coder) and in channel coding low-complexity rate compatible punctured PUM-based turbo codes). In the case of severe channel conditions, additional Reed-Solomon coding is applied across the packets. The scalable bitstream is split into multiple frames which are encoded separately. Fast rate optimal algorithms are used to determine suboptimal source channel symbol allocation. Experimental results given for different video sequences and channel conditions indicate good performance achieved at low complexity.
Introduction: Abstract— The paper describes a digital smear-desmear
technique (SDT) based on polyphase multilevel sequences
of unlimited length with good autocorrelation properties.
A design procedure for digital implementation of SDT is
defined and sequences with power efficiency higher than
50% are generated. These sequences are applied to the
design of digital smear/desmear filters and combined with
uncoded and coded ITU-T V.150.1 communication systems.
The impulse noise is modeled as a sequence of Poisson
arriving delta functions with gaussian amplitudes. The
impulse noise parameters are computed from experimental
data. Simulation results shows that the SDT filter design
method yields a significant improvement in bit error rates
for both systems subject to impulse noise, relative to systems
with no SDT. The technique also completely removes the
error floor caused by impulse noise.
Introduction: Turbo coding, a forward error correcting coding (FEC) technique, has made near Shannon Limit performance possible when Iterative decoding algorithms are used. Intersymbol interference (ISI) is a major problem in communication systems when information is transmitted through a wireless channel. Conventional approaches implement an equalizer to remove the ISI, but significant performance gain can be achieved through joint equalization and decoding. In this thesis, the suitability of turbo equalization as a means of achieving low bit error rate for high data communication systems over channels with intersymbol interference was investigated. A modified decision feedback equalizer algorithm (DFE) that provides significant improvement when compared with the conventional DFE is proposed. It estimates the data using the a priori information from the SISO channel decoder and also a priori detected data from previous iteration to minimize error propagation. Investigation was also carried out with Iterative decoding with imperfect minimum mean square error (MMSE) decision feedback equalizer, assuming soft outputs from the channel decoder that are independent identically distributed Gaussian random variables. The prefiltering method is considered in this thesis, where an all-pass filter is employed at the receiver before equalization to create a minimum phase overall impulse response. The band limited channel suffers performance degradation due to impulsive noise generated by electrical appliances. This thesis analysed a set of filter design criteria based on minimizing the bit error probability of impulse noise using digital smear filter.
Introduction: Mathematical analysis, supported by computer simulations is used to find a theoretical limit to cell size reduction in cellular wireless network in a shadowed fading environment. Information capacity measure based on the uplink of cellular wireless network is used for the analysis. Results show that at higher microwave carrier frequencies and smaller cell radius some of the second tier co-channel interfering cells (co-channel cells after the first six co-channel cells) becomes active. This causes a decrease in the information capacity of the cellular wireless network. The results also show that the decrease in the information capacity becomes bigger as the carrier frequency increases and cell size radius decreases.
Introduction: Adaptive multiuser receivers scheme for MIMO OFDM over Iterative-Equalization for Single-Carrier Transmission, which we refer to as Iterative AMUD MIMO OFDM. It involves the joint iteration of the adaptive minimum mean square error multiuser detection and decoding algorithm with prior information of the channel and interference cancelation in the spatial domain. A partially filtered gradient LMS (Adaptive) algorithm isalso applied to improve the convergence speed and tracking ability of the adaptive detectors with slight increase in complexity. The proposed technique is analyzed in slow and fast Rayleigh fading channels in MIMO OFDM systems. The Adaptive Multiuser Detection for MIMO OFDM system (AMUD MIMO OFDM) performs as well as the iterative equalization for single-carrier for higher modulation scheme. The LMS algorithm and maximum a posterior (MAP) algorithm are utilized in the receiver …
Introduction: Adaptive multiuser receivers scheme for MIMO OFDM over Iterative-Equalization for Single-Carrier Transmission, which we refer to as Iterative AMUD MIMO OFDM. It involves the joint iteration of the adaptive minimum mean square error multiuser detection and decoding algorithm with prior information of the channel and interference cancelation in the spatial domain. A partially filtered gradient LMS (Adaptive) algorithm isalso applied to improve the convergence speed and tracking ability of the adaptive detectors with slight increase in complexity. The proposed technique is analyzed in slow and fast Rayleigh fading channels in MIMO OFDM systems. The Adaptive Multiuser Detection for MIMO OFDM system (AMUD MIMO OFDM) performs as well as the iterative equalization for single-carrier for higher modulation scheme. The LMS algorithm and maximum a posterior (MAP) algorithm are utilized in the receiver …
Introduction: This paper presents an adaptive vector precoding schemes for the downlink multiuser multiple input multiple-output orthogonal frequency division multiplexing systems (MIMO OFDM) with multiple data streams per user. The zf precoder requires pseudo inversion of the channel matrix, where this operation is only optimum when the transmitter power is unconstrained. This paper presents efficient methods to reduce the computational load of the algorithm by interpolating the precoding and decoding matrices corresponding to different OFDM subcarriers. In the feedback scenario, the precoder matrix has to be designed for all subcarriers and can get positively large. The precoded MIMO OFDM systems will adapt to change in channel characteristics due to the automatic updating. This approach yields an improvement to the bit error rate probability by approximately an order of magnitude as compared to the ZF approach, utilizing other channel decomposition techniques. In comparison to Moore-Penrose pseudo inverse an increase in the capacity of the MIMO OFDM, with less computational complexity is achieved.
Introduction: The robust delivery of video over emerging wireless networks poses many challenges due to the heterogeneity of access networks, the variations in streaming devices, and the expected variations in network conditions caused by interference and coexistence. The proposed approach exploits the joint optimization of a wavelet-based scalable video/image coding framework and a forward error correction method based on PUM turbo codes. The scheme minimizes the reconstructed image/video distortion at the decoder subject to a constraint on the overall transmission bitrate budget. The minimization is achieved by exploiting the rate optimization technique and the statistics of the transmission channel.
Introduction: The need to accurately predict and make right decisions regarding crude oil price motivates the proposition of an alternative algorithmic method based on real-valued negative selection with variable-sized detectors (V-Detectors), by incorporating with fuzzy-rough set feature selection (FRFS) for predicting the most appropriate choices. The objective of this study is enhancing the performance of V-Detectors using FRFS for prices of crude oil. Applying FRFS serves to prune the number of features by retaining the most informative and critical features. The V-Detectors then trains and tests the features. Different radius values are applied for V-Detectors. Experimental outcome in comparison with established algorithms such as support vector machine, naïve bayes, multi-layer perceptron, J48, non-nested generalized exemplars, IBk, fuzzy-roughNN, and vaguely quantified nearest neighbor demonstrates that FRFS-V-Detectors is proficient and valuable for insightful knowledge on crude oil price. Thus, it can assist in establishing oil price market policies on the international scale.
Introduction: Mining agricultural data with artificial immune system (AIS) algorithms, particularly the clonal selection algorithm (CLONALG) and artificial immune recognition system (AIRS), form the bedrock of this paper. The fuzzy-rough feature selection (FRFS) and vaguely quantified rough set (VQRS) feature selection are coupled with CLONALG and AIRS for improved detection and computational efficiencies. Comparative simulations with sequential minimal optimization and multi-layer perceptron reveal that the CLONALG and AIRS produced significant results. Their respective FRFS and VQRS upgrades namely, FRFS-CLONALG, FRFS-AIRS, VQRS-CLONALG, and VQRS-AIRS, are able to generate the highest detection rates and lowest false alarm rates. Thus, gathering useful information with the AIS models can help to enhance productivity related to agriculture.
Introduction: The Real-Valued Negative Selection algorithms which are the focal point of this work generate their detector set based on the points of self data. Self data is regarded as the normal behavioural pattern of the monitored system. An anomaly in data alters the confidentiality and integrity of its content thereby causing a defect for making useful and accurate decisions. Therefore, to correctly detect such an anomaly, this study applies the real-valued negative selection with; fixed-sized detectors (RNSA) and variable-sized detectors (V-Detector) for classification and detection of anomalies. Classifier algorithms of Support Vector Machine (SVM) and K-Nearest Neighbour (KNN) are used for benchmarking the performances of the real-valued negative selection algorithms. Experimental results illustrate that RNSA and V-Detector algorithms are suitable for the detection of anomalies, with the SVM and KNN producing significant efficiency rates. It was also gathered that V-Detector yielded superior performances with relation to the other algorithms.
Introduction: This paper implements the real-valued negative selection with variable-sized detectors (V-Detectors) for projecting the right decision with respect to crude oil price. The Brent crude oil data is retrieved from US department of energy. Using varying radius values of the V-Detector, comparison in terms of detection rate and false alarm rate, with support vector machine, naïve bayes, multi-layer perceptron, J48, non-nested generalized exemplars, IBk, fuzzy-roughNN, and vaguely quantified nearest neighbor demonstrated that V-Detector is efficient and computationally effective. The experimental outcome can initiate international crude oil market policy making as the V-Detector is able to reach highest detection and lowest false alarm rates.
Introduction: Mining agricultural data with artificial immune system (AIS) algorithms, particularly the clonal selection algorithm (CLONALG) and artificial immune recognition system (AIRS) form the bedrock of this paper. A fuzzy-rough feature selection (FRFS) method is coupled with CLONALG and AIRS for improved detection and computational efficiency. Comparative simulations with sequential minimal optimization and multi-layer perceptron reveal that the CLONALG and AIRS produced significant results. Their respective FRFS upgrades namely; FRFS - CLONALG and FRFS - AIRS are able to generate highest detection rates and lowest false alarm rates. Thus, gathering useful information with the AIS models can help to enhance productivity related to agriculture.
Introduction: The ability of Negative Selection Algorithm (NSA) to solve a number of anomaly detection problems has proved to be effective. This paper thus presents an experimental study of negative selection algorithm with some classification algorithms. The purpose is to ascertain their efficiency rates in accurately detecting abnormalities in a system when tested with well-known datasets. Negative selection algorithm with some selected immune and classifier algorithms are used for experimentation and analysis. Three different datasets have been acquired for this task and a comparison performance executed. The empirical results illustrates that the artificial immune system of negative selection algorithm can achieve highest detection and lowest false alarm. Thus, it signifies the suitability and potentiality of NSA for discovering unusual changes in normal behavioral flow.
Introduction: The effect of climate change presents a huge impact on the development of a country. Furthermore, it is one of the causes in determining planning activities for the advancement of a country. Also, this change will have an adverse effect on the environment such as flooding, drought, acid rain and extreme temperature changes. To be able to avert these dangerous and hazardous developments, early predictions regarding changes in temperature and ozone is of utmost importance. Thus, neural network algorithm namely the Multilayer Perceptron (MLP) which applies Back Propagation algorithm (BP) as their supervised learning method, was adopted for use based on its success in predicting various meteorological jobs. Nevertheless, the convergence velocity still faces problem of multi layering of the network architecture. As consequence, this paper proposed a Functional Link Neural Network (FLNN) model which only has a single layer of tunable weight trained with the Modified Cuckoo Search algorithm (MCS) and it is called FLNN-MCS. The FLNN-MCS is used to predict the daily temperatures and ozone. Comprehensive simulation results have been compared with standard MLP and FLNN trained with the BP. Based on the extensive output, FLNN-MCS was proven to be effective compared to other network models by reducing prediction error and fast convergence rate.
Introduction: The effect of climate change presents a huge impact on the development of a country. Furthermore, it is one of the causes in determining planning activities for the advancement of a country. Also, this change will have an adverse effect on the environment such as flooding, drought, acid rain and extreme temperature changes. To be able to avert these dangerous and hazardous developments, early predictions regarding changes in temperature and ozone is of utmost importance. Thus, neural network algorithm namely the Multilayer Perceptron (MLP) which applies Back Propagation algorithm (BP) as their supervised learning method, was adopted for use based on its success in predicting various meteorological jobs. Nevertheless, the convergence velocity still faces problem of multi layering of the network architecture. As consequence, this paper proposed a Functional Link Neural Network (FLNN) model which only has a single layer of tunable weight trained with the Modified Cuckoo Search algorithm (MCS) and it is called FLNN-MCS. The FLNN-MCS is used to predict the daily temperatures and ozone. Comprehensive simulation results have been compared with standard MLP and FLNN trained with the BP. Based on the extensive output, FLNN-MCS was proven to be effective compared to other network models by reducing prediction error and fast convergence rate.
Introduction: Within the Artificial Immune System community, the most widely implemented algorithm is the Negative Selection Algorithm. Its performance rest solely on the interaction between the detector generation algorithm and matching technique adopted for use. Relying on the type of data representation, either for strings or real-valued, the proper detection algorithm must be assigned. Thus, the detectors are allowed to efficaciously cover the non-self space with small number of detectors. In this paper, the di_erent categories of detection generation algorithm and matching rule have been presented. Briey, the biologial and arti_- cial immune system, as well as the theory of negative selection algorithm were introduced. The exhaustive detector generation algorithm used in the original Negative Selection Algorithm laid the foundation at proferring other algorithmic methods based on set of rules in generating valid detectors for revealing anomalies.
Introduction: Within the Artificial Immune System community, the most widely implemented algorithm is the Negative Selection Algorithm. Its performance rest solely on the interaction between the detector generation algorithm and matching technique adopted for use. Relying on the type of data representation, either for strings or real-valued, the proper detection algorithm must be assigned. Thus, the detectors are allowed to efficaciously cover the non-self space with small number of detectors. In this paper, the di_erent categories of detection generation algorithm and matching rule have been presented. Briey, the biologial and arti_- cial immune system, as well as the theory of negative selection algorithm were introduced. The exhaustive detector generation algorithm used in the original Negative Selection Algorithm laid the foundation at proferring other algorithmic methods based on set of rules in generating valid detectors for revealing anomalies.
Introduction: Grid computing, a new and broad area of research, aims at sharing available information and resources through the use of computers over the network. To use the new applications of grid, it is necessary to adapt the modern software components and assembled information resources in a flexible format. Web services incorporate the necessary capabilities in achieving this goal called grid services. Due to the exponentially increasing amount of data, documents, resources and services available on the web, finding an acceptable agreement between the user and the abilities of web or grid service as well as forming an appropriate composition of service components for performing requested operation are critical issues. Measuring the similarity of services is an important and valuable solution that is used in some practical reasoning such as replacement of a service with another and combination of services and applications. Also, because the measuring the service similarity needs an appropriate semantic model, therefore, in this paper a semantic model based on OWL ontology language for services is presented and thus, similarity measure is provided. We find a semantic model for services and then provide a method for measuring the similarity between two services. A mathematical model for solving given problems is also proposed. The results evaluated by F1 measure obviously show the improvement of accuracy against previous method.
Introduction: The roles played by Enterprise Resource Planning
(ERP) systems in any organizations in achieving operational
excellence and competitive advantage cannot be
underestimated. However, the cost of implementing traditional
ERP has been observed to be a bane for most Small and
Medium Enterprises (SMEs) which are globally known as the
major drivers of most agile economies. Cloud computing is a
paradigm technology concept that affords the SMEs
opportunities of affordable services in which ERP can be
Cloud-hosted and rented on pay-per-use basis, which does not
require a great deal of initial capital to ensure business
continuity in a highly competitive market. There are a lot of
providers offering ERP as Software-as-a-Service (SaaS), the
SMEs therefore is being faced with the challenge of selecting a
provider with Quality of Service (QoS) suitable enough to meet
the customized requirements of the organizations. A model is
presented in this paper which seeks to address this selection
challenge. Apart from the suitability efforts, the model also
further attempts to select the cheapest among a few selected
providers already found suitable for the SMEs.
Introduction: Interdisciplinary Journal of Contemporary Research in Business, 3(7), 93-101.
Introduction: Directory services facilitate access to information organized under a variety of frameworks and applications. The Lightweight Directory Access Protocol is a promising technology that provides access to directory information using a data structure similar to that of the X.500 protocol. IBM Tivoli, Novell, Sun, Oracle, Microsoft, and many other vendor features LDAP-based implementations. The technology’s increasing popularity is due both to its flexibility and its compatibility with existing applications. A directory service is a searchable database repository that lets authorized users and services find information related to people, computers, network devices, and applications. Given the increasing need for information — particularly over the Internet — directory popularity has grown over the last decade and is now a common choice for distributed applications. Lightweight Directory Access Protocol (LDAP) accommodates the need of high level of security, single sign-on, and centralized user management. This protocol offers security services and integrated directory with capability of storage management user information in a directory. Therefore at the same time the user can determine application, service, server to be accessed, and user privileges. It is necessary to realize files sharing between different operating systems in local area network. Samba software package, as the bridge across Windows and Linux, can help us resolve the problem. In this paper, we try to explore previous literature on this topic and also consider current authors work then come out with our views on the subject matter of discussion based on our understanding.
Introduction: The Information Technology world is developing so fast and it is been reported that Open Source tools will eventually take over proprietary tools in no to distant future. The Open Source Community is integrating its products with that of the proprietary ones and the integration of Windows machines into Linux network is evident of such practices. The purpose of this project is to implement Samba with OpenLDAP in a simulated environment. This implementation is conducted within a virtual environment by simulating the setup of Linux and Windows Operating systems by reducing physical setup of machines. Samba will act as an interface between Linux and Windows, files will be accessible to both server and client. OpenLDAP stores the user accounts and configuration files. A performance test carried out on Samba determining effect on CPU power and Memory usage shows a decrease in the CPU power and an increase in Memory usage.
Introduction: Enterprise Resource Planning (ERP) systems provided as a service in the cloud is offering immense assistance for the Small and Medium sized Enterprises (SMEs) with respect to cost effectiveness and affordability, to be able to compete favorably and fairly with their Large Enterprises (LE) counterparts who have the financial wherewithal to adopt the rather expensive traditional or on-premise ERP Systems. However, to be able to achieve such numerous benefits such as economies of scale, improved flexibility, reduced capital cost, improved accessibility, and so on, many service subscribers (tenants) often share the same remote physical infrastructure put in place by the cloud service providers (CSPs). This multi-tenancy concept however introduces a high level of security and privacy risks unique to cloud services, such as attacks from other consumers, who may be competitors or simply hackers, sharing the same infrastructure. Hence, it becomes a challenge for the SMEs to select a suitable CSP whose security and privacy mechanisms most meet the security requirements of the organizations. We critically appraise some selected frameworks for the selection of cloud computing and, more specifically cloud ERP providers in order to be able to identify dimensions and measure of selection. We compare the frameworks based on their components, criteria for selection in the approaches and the suitability for the SMEs. We discovered that there is a link between frameworks of evaluation, ranking and selection of cloud providers. In our review, we found out that current selection methods are complementary one to another in the sense that they select …
Introduction: Enterprise Resource Planning (ERP) systems automate and integrate business management activities thereby aiding the organization achieve operational excellence and competitive advantage. However, traditional ERP has been observed to be too costly for most Small and Medium Enterprises (SMEs) which are known to be the economic agents of rural development globally. Emergence of Cloud computing offers the SMEs opportunities of accessing cloud-hosted infrastructure to evade huge initial capital. As there are myriads of providers offering ERP as Software-as-a-Service (SaaS), there arises the challenge as per choosing a provider with Quality of Service (QoS) that would be suitable to meet the organizations’ customized requirements. The paper presents a model which not only seeks to address this challenge, the model goes a step further to select the most affordable among a selected few providers that …
Introduction: Enterprise Applications (EAs) aid the organizations achieve operational excellence and competitive advantage. Over time, most Small and Medium Enterprises (SMEs), which are known to be the major drivers of most thriving global economies, use the costly on-premise versions of these applications thereby making business difficult to competitively thrive in the same market environment with their large enterprise counterparts. The advent of cloud computing presents the SMEs an affordable offer and great opportunities as such EAs can be cloud-hosted and rented on a pay-per-use basis which does not require huge initial capital. However, as there are numerous Cloud Service Providers (CSPs) offering EAs as Software-as-a-Service (SaaS), there is a challenge of choosing a suitable provider with Quality of Service (QoS) that meet the organizations’ customized requirements. The proposed model takes care of that …
Introduction: Enterprise Resource Planning (ERP) systems automate and integrate business management activities thereby aiding the organization achieve operational excellence and competitive advantage. However, traditional ERP has been observed to be too costly for most Small and Medium Enterprises (SMEs) which are known to be the economic agents of rural development globally. Emergence of Cloud computing offers the SMEs opportunities of accessing cloud-hosted infrastructure to evade huge initial capital. As there are myriads of providers offering ERP as Software-as-a-Service (SaaS), there arises the challenge as per choosing a provider with Quality of Service (QoS) that would be suitable to meet the organizations’ customized requirements. The paper presents a model which not only seeks to address this challenge, the model goes a step further to select the most affordable among a selected few providers that are suitable for the SMEs to keep them agile and competitive.
Introduction: Enterprise Resource Planning (ERP) systems automate and integrate business management activities thereby aiding the organization achieve operational excellence and competitive advantage. However, traditional ERP has been observed to be too costly for most Small and Medium Enterprises (SMEs) which are known to be the economic agents of rural development globally. Emergence of Cloud computing offers the SMEs opportunities of accessing cloud-hosted infrastructure to evade huge initial capital. As there are myriads of providers offering ERP as Software-as-a-Service (SaaS), there arises the challenge as per choosing a provider with Quality of Service (QoS) that would be suitable to meet the organizations’ customized requirements. The paper presents a model which not only seeks to address this challenge, the model goes a step further to select the most affordable among a selected few providers that are suitable for the SMEs to keep them agile and competitive.
Introduction: Enterprise Resource Planning (ERP) systems automate and integrate business management activities thereby aiding the organization achieve operational excellence and competitive advantage. However, traditional ERP has been observed to be too costly for most Small and Medium Enterprises (SMEs) which are known to be the economic agents of rural development globally. Emergence of Cloud computing offers the SMEs opportunities of accessing cloud-hosted infrastructure to evade huge initial capital. As there are myriads of providers offering ERP as Software-as-a-Service (SaaS), there arises the challenge as per choosing a provider with Quality of Service (QoS) that would be suitable to meet the organizations’ customized requirements. The paper presents a model which not only seeks to address this challenge, the model goes a step further to select the most affordable among a selected few providers that are suitable for the SMEs to keep them agile and competitive.
Introduction: In this paper, we extend variational iteration method (VIM) to find approximate solutions of linear and nonlinear thirteenth order differential equations in boundary value problems. The method is based on boundary valued problems. Two numerical examples are presented for the numerical illustration of the method and their results are compared with those considered by [1,2]. The results reveal that VIM is very effective and highly promising in comparison with other numerical methods.
Introduction: This paper presents a robust signature verification and forgery detection system using fuzzy modeling
technique. The features of various handwritten signatures are sampled with proper analysis and
encapsulated to devise an effective verification system. Grid method was used to extract features angles for
detention of forgeries and verification of genuine signatures. Exponential membership function was used to
fuzzified the derived functions, and modified into structural parameters suitable to adapt to any possible
variations that may result from handwriting styles and also to reflect any other factors due to scripting of a
signature. The proposed system is tested on a large database of signatures obtained from 40 subjects.
Introduction: Countering Cyber Trasspass – A proposed Framework. Advances in Multidisciplinary & Scientific Research 3 (3): 41-50
Introduction: In this information age knowledge acquired is always spread through the web. Currently on the exponential growth of the
available information on the social media interface (for example every minute on the internet over 50 million information are
upload and over 50 hours of videos are uploaded on YouTube alone) and therefore it is physiologically impossible to follow the
information flow in real time hence make it more difficult for some country to thrive in area of research with a foreign
languages. These foreign languages therefore brings numerous perils, including death which may befall a language and render
its growth or relevance somewhat useless, lending to the ‘birth’ of a population with little regard for their own languages and
therefore slow down the technology advancement of the nation. This research work extracts factors responsible for Yoruba
Language in a state being annihilated. Questionnaires were administered and returned to generated dataset from the responses
and Gain Ratio and Relief f techniques from Weka 3.7.9 while a threshold was set for each technique and the common was
responsible for Yoruba Language annihilation. The result showed that lack of commitment to indigenous language use, Colonia
legacy and in-effective language planning by the government are the factors that are mostly responsible for Yoruba language
annihilation. These factors were also responsible for slow development of technology of a nation.
Introduction: Using survey design, this study investigated bank customers’ confidence with electronic
payment channels services in Abuja Municipal Area Council (AMAC), a Nigerian
municipality. Structured questionnaires were used to collect data and were analysed
using descriptive statistical method. The study shows that, ease of use of electronic
payment system platforms is a major factor with online banking activities. Excellent
customer service is the primary reason for maintaining bank relationship. Based on the
findings of the study, recommendations were made on how to further strengthen bank
customers’ confidence towards electronic payment systems.
Introduction: Internet Traffic Engineering is defined as that aspect of Internet network engineering
dealing with the issue of performance evaluation and optimization of operational IP
networks. Traffic Engineering encompasses the application of technology and scientific
principles to the measurement, characterization, modeling, and control of Internet traffic.
Enhancing the performance of an operational network, at both traffic and resource levels,
are major objectives of Internet engineering. Traffic oriented performance include packet
transfer delay, packet delay variation, packet loss, and throughput. Packet transfer delay
is a concept in packet switching technology. The sum of store-and-forward delay that a
packet experiences in each router gives the transfer or queuing delay of that packet
across the network. Packet transfer delay is influenced by the level of network
congestion and the number of routers along the way of transmission. Packet loss occurs
when one or more packets of data travelling across a computer network fail to reach their
destination. Packet loss is distinguished as one of the three main error types encountered
in digital communications; the other two being bit error and spurious packets caused due
to noise. The fraction of lost packets increases as the traffic intensity increases. Therefore,
performance at a node is often measured not only in terms of delay, but also in terms of
the probability of packet loss.
Introduction: A Text Classifier Model for Categorizing Feed Contents Consumed by a Web Aggregator
Introduction: The concept of data mining, which has become a promising field because of its applications in various fields, is used in this work for strategic equipment maintenance in telecommunication network. Efficient maintenance of equipment in large telecommunication networks is difficult and complex. Thus, there is need for intelligent systems to guide engineers in proper maintenance of equipment in telecommunication network installations. The idea is to apply modified Apriori frequent pattern algorithm to mine frequent faulty events and identity association rules among items in telecommunication network alarm database. We implemented the novel approach on faulty events database of a GSM company in Nigeria. The result shows a promising tool that is much needed for intelligent decision-making in equipment maintenance in telecommunication installations.
Introduction: An analysis of Ayo is presented in this paper. The game is briefly described and it is shown that myopic decision guarantees solution to the game. The “odu” concept is discussed and it is shown that this strategy does not alter the solution methodology applied to solve the game without it. It is shown that the payoff matrix does not always have a saddle-point. Nevertheless, solution exists.
Introduction: Decision making plays an important role in the life of every living creature. Virtually on daily basis, people must make one or more decision. A faulty decision can lead to defeat in any competition. This paper presents the process of making decisions on the basis of knowledge of game playing as a major key in defining human characteristics. We simulated Ayo game playing on a digital computer and empirically evaluated the behavior of the prototype simulation. Empirical judgment was carried out on how experts play Ayo game as a means of evaluating the performance of the heuristics used to evolve the Ayo player in the simulation. A paper-based questionnaire was designed and administered to the Ayo game players which were used for the assessments of players’ perceptions of the prototype simulation, which gives room for statistical interpretation. This projects a novel means of solving the problem of decision making in move selections in computer game-playing of Ayo game.
Introduction: Ayo Game, Some Practical Difficulties and Efficiency Considerations
Introduction: Researchers have used many techniques in designing intrusion detection systems (IDS) and yet we still do not have an effective IDS. The interest in this work is to combine techniques of data mining and expert systems in designing an effective anomaly?based IDS. Combining methods may give better coverage, and make the detection more effective. The idea is to mine system audit data for consistent and useful patterns of user behaviour, and then keep these normal behaviours in profiles. An expert system is used as the detection system that recognizes anomalies and raises an alarm. The evaluation of the intrusion detection system design was carried out to justify the importance of the work.
Introduction: The goal of our work is to discuss the fundamental issues of privacy and anomaly?based intrusion detection systems (IDS) and to design an efficient anomaly?based intrusion IDS architecture where users' privacy is maintained.
Introduction: This paper describes an approach to visualizing concurrency control (CC) algorithms for real-time database systems (RTDBs). This approach is based on the principle of software visualization, which has been applied in related fields. The Model-View-controller (MVC) architecture is used to alleviate the black box syndrome associated with the study of algorithm behaviour for RTDBs Concurrency Controls. We propose a Visualization "exploratory" tool that assists the RTDBS designer in understanding the actual behaviour of the concurrency control algorithms of choice and also in evaluating the performance quality of the algorithm. We demonstrate the feasibility of our approach using an optimistic concurrency control model as our case study. The developed tool substantiates the earlier simulation-based performance studies by exposing spikes at some points when visualized dynamically that are not observed using usual static graphs. Eventually this tool helps solve the problem of contradictory assumptions of CC in RTDBs.
Introduction: Decision making plays an important role in the life of every living creature. Virtually on daily basis, people must make one or more decision. A faulty decision can lead to defeat in any competition. This paper presents the process of making decisions on the basis of knowledge of game playing as a major key in defining human characteristics. We simulated Ayo game playing on a digital computer and empirically evaluated the behavior of the prototype simulation. Empirical judgment was carried out on how experts play Ayo game as a means of evaluating the performance of the heuristics used to evolve the Ayo player in the simulation. A paper-based questionnaire was designed and administered to the Ayo game players which were used for the assessments of players’ perceptions of the prototype simulation, which gives room for statistical interpretation. This projects a novel means of solving the problem of decision making in move selections in computer game-playing of Ayo game.
Introduction: The major goal in defining and examining game scenarios is to find good strategies as solutions to the game. A plausible solution is a recommendation to the players on how to play the game, which is represented as strategies guided by the various choices available to the players. These choices invariably compel the players (decision makers) to execute an action following some conscious tactics. In this paper, we proposed a refinement-based heuristic as a machine learning technique for human-like decision making in playing Ayo game. The result showed that our machine learning technique is more adaptable and more responsive in making decision than human intelligence. The technique has the advantage that a search is astutely conducted in a shallow horizon game tree. Our simulation was tested against Awale shareware and an appealing result was obtained.
Introduction: In playing Ayo game, both opening and endgames are often stylized. The opening is very interesting with both players showing skills by the speed of their movements. However, there exists an endgame strategy in Ayo game called Completely Determined Game (CDG) such that its usefulness for ending a game should be apparent. In this paper, we present the CDG as a class of endgame strategy and describe its configuration and detailed analysis of its winning positions that generates integer sequence, and some self-replicating patterns
Introduction: The success or otherwise of Software Engineering (SE) activities depends on the interactions
among software engineers. Consequently, effective interactions depend largely on personality
traits, which is a consistent and long-lasting tendency in behaviour. In psychology, five major
trait factors (The Big Five Factors) have been generally used to assess personality of people. But,
these might not be adequate in SE because of the required technical and cognitive skills. In this
work, we first present Cognitive Ability as an additional factor that must be measured in order to
adequately assess personality in SE. A research survey was conducted in order to capture personality requirements in SE. Based on the result of the survey conducted, we develop a model for
assessing personality traits in SE. We then design an assessment technique that is based on responses to some well-structured and deductive on-line questions. The implementation of the
model using Visual Basic resulted in a much-needed tool that can guide intending software engineers in choosing area of specialization in SE based on their personality traits.
Introduction: From queuing system approach, a compute intensive application of a single processor computer system can be defined as any application of a single processor computer system where the arrival rate of processes into the processor queue is greater than the departure rate of the processes from the processor. on the other hand, a non-compute intensive application can be defined as any application where the arrival rate is less than the departure rate. A single processor computer system can be used for compute intensive and non-compute intensive applications. In a compute intensive application, the processor is busy most of the time because there is always job to be executed. This paper, therefore, aims at using a novel and efficient queuing approach to model some of the performance metrics of compute intensive applications of a single processor computer system.
Introduction: The XML standard adopted for the interoperability among Web services had played prominent role in enhancing systems/application integration and also facilitates linking up clientpsilas demands through loosely couple platform. However, the use of this technology has a major disadvantage of lacking in semantic representations of the contents in the Web and makes the service discovery scheme of the UDDI inefficient. Adding semantic features to Web services has a long role to play in facilitating automatic publishing, discovery, composition, and usage of these numerous services available on the Web which are dynamically published and discovered. In this paper, we applied the use of semantic registry-based system meant for personalizing car Web services' discovery. We maintained an OWL-based ontology for the car service together with a catalogue that keeps track of the published services for easy discovery. The semantic registry-based approach enhances the service discovery and guarantees quality of service by ensuring satisfaction of userpsilas requests which Web service personalization is meant to achieve.
Introduction: Intrusion detection systems become very important computer security mechanisms as computer break-ins are getting more common everyday. Intrusion detection system (IDS) monitors computers and networks for any set of actions that attempt to compromise the integrity, confidentiality or availability of computer resources. The goal of this paper is to discuss the fundamentals of IDS and to create awareness on why IDS should be embraced. A users study was carried out to understand the perceptions of individuals: organisations and companies on the use of IDS. Summary of problems of en/rent IDS designs and the challenges ahead are presented. We also look tit what should be the new approaches or future directions m IDS design so as to eliminate these shortcomings.
Introduction: This study investigated the inhibitory effects of Sapium ellipticum (SE) (Hochst) Pax leaf extract on some carbohydrate metabolizing enzymes, pancreatic ?-amylase and intestinal ?-glucosidase activities in vitro. The inhibitory potential of SE extract was measured against Quercetin. SE extract in a dose dependent pattern significantly inhibited the activity of pancreatic ?-amylase by 67.2% at 10 mg/mL. This effect was comparable to that of quercetin which offered 82.6% ?-amylase inhibition. In terms of intestinal ?-glucosidase activity, the inhibitory effect of the extract was significantly lower than that of quercetin at all investigated concentrations. At 10 mg mL?1 (maximum tested concentration), SE extract exhibited 35.8% inhibitory activity on ?-intestinal glucosidase compared to the 74.3% exhibited by Quercetin at the same concentration. Phytochemical analysis results showed that SE contained 74 ± 3.12 milligram Gallic acid equivalents of total phenols and 67.2 ± 2.04 milligram Quercetin equivalents of flavonoids per gram of extract. Fourier Transformed Infra red spectroscopy (FT-IR) of SE extract revealed the presence of active functional groups reminiscence of polyphenols. Alpha amylase and ?-glucosidase activities (in vivo) greatly contribute to postprandial hyperglycemia which is a great risk factor for type 2 diabetes mellitus. The inhibitory potential of SE extract on these enzymes as observed in this study suggests a positive and probable role of the extract in the management and treatment of diabetes mellitus, particularly, type 2.
Introduction: Arsenic poisoning is a major environmental event affecting millions worldwide and its treatment with chelating agents has
met with limited success. While arsenic toxicity affects multiple systems in the human body, its mode of action has not
been fully elucidated. The present study therefore, investigated the possible protective effects of catechin against
hepatorenal damage and dyslipidemia induced by arsenic exposure. Rats were exposed to arsenic (100 ppm) through their
drinking water and were treated with catechin (40 mg/kg and 80 mg/kg, body weight) for 30 days. Arsenic exposure
resulted in liver dysfunction obvious with increased activities of the hepatic enzymes alanine aminotransferase (ALT),
alkaline phosphatase (ALP) and aspartate aminotransferase (AST). This was accompanied with significant elevation of
kidney function markers urea and creatinine (p < 0.05). Furthermore, arsenic caused the distortion of lipid metabolism
resulting in hypercholesterolemia, hypertriglyceridemia and increased plasma phospholipid in the animals. Co-treatment
with catechin effectively protected against arsenic-mediated hepatotoxicity, prevented renal damage and restored lipid
homeostasis in the rats. The present data indicate the ability of catechin to potentially prevent arsenic-induced nephrohepatotoxicity and dyslipidemia in rats.
Introduction: Arsenic and di-(2-ethylhexyl) phthalate (DEHP) are environmentally ubiquitous and epidemiologically important toxic agents that millions of people are currently exposed to, worldwide. Although the adverse impact due to exposure to either arsenic or DEHP are documented, the toxicological effects of co-exposure to these agents are largely unknown. In this study, exposure to these chemicals was investigated for their effects on ATPase activities in the brain, liver and kidney of rats. Male Wistar rats were exposed daily to 100 mg L-1 arsenic via drinking water and to 100 mg DEHP kg-1 body weight in corn oil either individually or concurrently for 30 days. Toxicity was assessed by evaluating changes in body and organ weights, as well as, Na+/K+-, Ca2+-, Mg2+- and total ATPase activities in the brain, liver and kidney. Exposure to either arsenic or DEHP resulted in drastic reduction in activities of the enzymes in the compartments investigated, except in the brain where Na+/K+- and Mg2+- ATPases had their activities significantly increased. Also, DEHP displayed no effect on the total ATPase and Ca2+ ATPase in the kidney and brain, respectively. Interestingly, co-exposure to these toxicants significantly stimulated the activities of all these enzymes in the brain. In this compartment, combined treatment resulted in an additive interaction between the toxicants and a potentiation effect of arsenic on DEHP with regards to the Na+/K+- ATPase activity and Ca2+- ATPase activity, respectively. Our findings demonstrate tissue specific response to combined arsenic and DEHP exposure in rats with the effect on the brain significantly different from other compartments.
Introduction: Diabetes is characterized by hyperglycaemia with alterations of lipid parameters. The effects of Aloe vera (A.V) gel extract on lipid profiles of streptozotocin-induced diabetic rats were investigated. Seventy-two male albino rats were randomly divided into six groups of 12 rats each; control, diabetic control, 4 ml/kg and 8 ml/kg body weight (b.w.) A.V, 10 mg/kg b.w. glibenclimide and non-diabetic 8 ml/kg b.w. A.V groups. They were treated for 14 and 28 days. The plasma and HDL lipid profiles (triacylglycerols, cholesterol and phospholipids) of the diabetic rats were significantly (p<0.05) increased, while those of the VLDL+LDL, RBC, RBC membrane and organs were observed to be significantly (p<0.05) reduced, when compared to the control after 14 and 28 days of treatment. A.V gel extract significantly (p<0.05) ameliorated the disruptions observed in the lipid profiles of the diabetic and thus provide a scientific rationale for the use of Aloe vera as a therapeutic agent.
Introduction: To investigate whether amoxillin and pefloxacin perturb lipid metabolism.
Introduction: Strophanthus hispidus is a multipurpose medicinal plant which has been reported to have diverse medicinal uses in the treatment of sexual diseases, malaria, dysentery, stroke, heart failure, gonorrhea, arthritis, diabetes, snake bites, constipation, inflammatory, rheumatism and ulcers. This study investigated the hypoglycemic and antioxidant effects of Strophanthus hispidus aqueous root extract, using the activities of superoxide dismutase, total peroxidases, gamma glutamyl transferase, glutathione - S- transferase , glutathione peroxidase, glutathione reductase, as well as the concentrations of glucose, glutathione, vitamin C, nitric oxide, total thiols and malondialdehyde as indices. Forty rats were divided into five (A, B, C, D and E) Groups. Group A served as control, Group B were streptozotocin – induced diabetes mellitus untreated rats, Group C were streptozotocin – induced diabetes mellitus rats treated with 600µg/ kg body weight of glibenclamide, Group D and E were streptozotocin – induced diabetes mellitus rats treated with 500mg/kg and 1000mg/kg body weight of the extract respectively for fourteen consecutive days. The concentrations of blood glucose, nitric oxide and malondialdehyde were significantly (p< 0.05) decreased in all the Groups that received the different doses of extract as compared with the negative control Group (Group B). In conclusion, Strophanthus hispidus aqueous root extract exhibited hypoglycemic and antioxidant functions.
Introduction: To investigate the effects of aluminum chloride (AlCl3) in the deviation of tissue lipid profiles and ways to reduce its effect using antioxidant vitamins C and E, thirty-six male albino rats (120-150g) were divided into six groups with six rats each. Group (1) received normal saline and served as control, Group (2) was administered with AlCl3 (20mg/kg body weight b.wt)), Group (3) was administered with vitamin C (200mg/kg b.wt), Group (4) was administered with vitamin E (200mg/kg b.wt), Groups (5) and (6) were administered aluminium (20mg/kg b.wt) along with vitamins C and E (200mg/kg b.wt) respectively. At the end of the experiment, blood samples and organs (liver, testis, heart, kidney and brain) were harvested and used for lipid profile determination. The results showed that oral administration of aluminum significantly (p<0.05) increased cholesterol level in plasma and VLDL+LDL and significantly decreased in erythrocyte, HDL and testis. Cholesterogenesis was induced in the brain, liver, kidney and heart. Plasma and VLDL+LDL triglyceride were significantly (p<0.05) increased while erythrocyte and brain triglyceride were significantly decreased. Plasma, VLDL+LDL and brain phospholipid levels were significantly (p<0.05) decreased and that of erythrocyte significantly increased. There was no significant difference (p>0.05) in rats supplemented with vitamin C and vitamin E compared with control. The vitamins significantly attenuated the affected lipid levels in the tissues affected. It was concluded that administration of vitamin C and vitamin E supplements may be used as therapies against the effects of Aluminium exposure on lipids.
Introduction: The anthropometric measurements of some apparent healthy Babcock University students (53 male and 47 female) were investigated in this study with a view to estimating the various anthropometric parameters, blood pressure components and hepatocellular injury indices (Aspartate aminotransferase - AST, Alanine aminotransferase - ALT, and Alkaline phosphatase - ALP) in different blood groups. Blood pressure, fasting plasma glucose (FPG), AST, ALT, ALP, weight, height, unblical circumference (UC), waist circumference (WC), hip circumference (HC), were determined using standard procedures; body mass index (BMI), body fat percentage (BF%), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and other body composition [body surface area (BSA), fat free body mass (FFBM), fat mass, total body water (TBW), intracellular fluid (ICF), extracellular fluid (ECF)] were calculated to assess overweight and obesity. While no significant difference (p > 0.05) was observed in the age, diastolic blood pressure (DBP), heart rate, FPG, weight, BMI, BSA, UC, WC, HC and WHR values of male when compared with the female counterpart; a significant (p < 0.05) decrease was observed in BF%, fat mass and WHtR, however a significant (p < 0.05) increase was found in systolic blood pressure (SBP), pulse pressure (PP), mean arterial pressure, height, FFBM, TBW, ICF and ECF of male when compared with the female subjects. No significant difference (p > 0.05) was observed in the activities of AST, ALT and ALP of male when compared with the female counterpart. Also there was no significant difference in AST, ALT when stratified according to various ABO blood groups of both male and female subjects. A significant positive relationship was observed between the ALP and FFBM (r = 0.369, p < 0.01); and BSA (r = 0.284, p < 0.01) male. Also AST significantly correlated positively with WC (r = 0.448, p < 0.01), HC (0.292, p < 0.05), UC (r = 0.402, p < 0.05), WHR (r = 0.410, p < 0.01) and WHtR (r = 0.429, p < 0.01) in the female subjects. ALP was directly correlated significantly with fat mass (r = 0.289, p < 0.05) in the female subjects. Thus these findings in young adults suggest potential clinical utility of including WC, HC, UC, WHR, WHtR as biomarkers in liver dysfunction and cardiovascular diseases assessment formulations.
Introduction: Lead has been implicated in the induction of reactive species production, leading to organ dysfunctions. The ameliorative roles of ascorbate and chelators in acute lead poisoning were comparatively studied in thirty-five male Wistar rats (150-200g), segregated into 5 groups (n=7/Group): group 1(administered normal saline),ª¤? groups 2-5 were orally exposed to 75mg/kg body weight lead acetate (PbAc) daily for 14 days. Pre-therapy blood samples were collected to ascertain blood lead level (BLL) and catalase activity 24hours after the last PbAc exposure. Groups 3, 4, and 5 were then treated with 30mg/kg body weight D-penicillamine; 30mg/kg body weight succimer; and 500mg/kg body weight ascorbate respectively for 10 days, followed by the assay for indices of oxidative stress, hepatic and renal dysfunctions.ª¤? Results obtained showed significantly elevated BLL in the four groups exposed to PbAc. which were significantly reversed about 2 folds in groups 3-5 after therapeutic interventions. Pre-therapy blood catalase activity of the PbAc treated groups was significantly (p<0.05) reduced by 39% when compared with the control group, however ascorbate significantly (p<0.05) increased catalase activity by 2 folds above the control; decreased plasma activities of alanine transaminase and aspartate transaminase, blood urea nitrogen and creatinine among the groups administered therapeutics. These findings indicate that ascorbate is more effective
Introduction: Studies were carried out to compare the effects of different edible oils (olive, turkey, palm, groundnut and soya) on lipidomics of blood and organs of rats. Thirty-six male albino rats divided into six groups (n = 6) were fed compounded diets without oil (control) and with different oils (10%) each ad libitum for twenty-eight days. Lipid profiles of tissues (blood, brain, heart and liver) and Hydroxymethylglutaryl CoA (HMG CoA) reductase activity in brain and liver were determined. All edible oil-containing diets (especially groundnut and soya oils) significantly reduced (p<0.05) weight gain and daily growth rate. Condition factor was significantly decreased (p<0.05) only in groundnut and increased in turkey oil fed groups compared with other diets. Different lipidomic patterns were elicited by the different oils compared with control. Significant decreases (p<0.05) were observed in level of cholesterol in plasma (olive and turkey oils) and heart (all oil diets) while increases were observed in HDL (olive, groundnut and soya oils), VLDL-LDL (olive, turkey and palm oils), RBC (all oil diets except olive oil group), brain (groundnut and soya oils) and liver (olive and turkey oils). HMG-CoA reductase activity significantly increased in liver of olive, soya and palm oil fed groups and brain (all oil diets) but decreased in liver of groundnut oil group. Triacylglycerol level significantly increased (p<0.05) in plasma and RBC of palm oil group, HDL (turkey oil) and VLDL-LDL (olive, turkey and palm oils) while it decreased in plasma (groundnut and soya oils), brain (all oil diets) and heart (palm and groundnut oils). Phospholipid levels increased significantly (p<0.05) in RBC (all oil diets except the olive), plasma and VLDL-LDL (all oil diets), brain (soya bean oil) and heart (turkey oil). The results indicated that olive, groundnut and soya bean oils are more beneficial to health compared with palm and turkey oils which may predispose to cardiovascular disease.
Introduction: Obesity, resulting from energy imbalance caused by an increased ratio of caloric intake to energy expenditure is a
global health problem. This study investigated the effects of Sorghum bicolor leaf extracts (SBE) on blood lipid
levels in high fat diet-induced obese rats. Sorghum bicolor leaf was extracted with 70% ethanol using Soxhlet
extractor. Male Wistar rats (n=36) divided into six groups: (A) normal control, (B) obese control (High Fat Diet –
HFD), (C) HFD+150 mg/kg body weight SBE (first treatment), (D) HFD+300 mg/kg body weight SBE
(second treatment), (E) HFD+600 mg/kg body weight SBE (third treatment) and (F) HFD+ 1200 mg/kg body
weight SBE (fourth treatment) were used. The SBE was administered orally to the animals daily for 28 days. Body
weight was taken weekly and Lee index was calculated alongside. Plasma, erythrocytes and lipoproteins' lipid
profiles were determined using spectrophotometric methods. Results from the study revealed that generally,
SBE significantly reduced (p<0.05) the levels of cholesterol, phospholipids, triacylglycerol by varying levels, in
the various blood compartments of the obese animals. It was observed that SBE caused a significant (p<0.05)
decrease in plasma cholesterol level of the fourth treatment group. Also, SBE significantly (p<0.05) reduced the
elevated atherogenic and coronary risk indices by 50%. This study suggests that SBE might be useful in the
management of obesity and its co-morbid conditions.
Introduction: Malaria, a disease of antiquity, has proved to be
a formidable deterrent to the cultural and socialeconomic progress of man in tropical and subtropical zones of the world. Recently, one of the
major problems in malaria control is drug
resistance. Therefore, this study was designed to
elucidate the potentials of Croton zambesicus
leaf extract in the treatment of malaria as well as
its biochemical and histopathological effects as
an antiplasmodial agent.
Introduction: Epidemiological studies have found a progressive increase in
the prevalence of hypertension and type 2 diabetes mellitus
(T2DM) with increasing body fat accummulation and
complex interactions among hormonal, homodynamic and
nutritional factor [1-3]. Obesity, T2DM and hypertension
are common and important problems in primary care
[4-6]. In the recent decade many prospective and crosssectional studies have been done in order to evaluate the
anthropometric measurement methods to assess patients
with elevated blood pressure and fasting plasma glucose,
which are dominant cardiovascular risk factor [5-7]. Different
anthropometric measurements like body mass index (BMI),
waist circumference (WC), waist-to-hip ratio (WHR), waistto-height ratio (WHtR), subscapular thickness or triceps
skin fold (TSF) measurement as a part of index of trunk
or peripheral skin folds are investigated for this purpose [7-
9]. Body mass index (BMI) is widely used for classification
of overweight and obesity, but it does not account for the
wide variation of the fat distributions. In addition, not all
overweight or obese patients have these metabolic diseases,
and vice versa. Therefore, there is currently overwhelming
evidence of central (abdominal or visceral) obesity as a
greater risk factor for cardiovascular diseases (CVD) than
general obesity [2, 3].
While these simple clinical concepts may be well-accepted
among many clinicians and researchers, and assumed to
be readily accessible in the medical literature, primary care
physicians are confronted by a remarkable heterogeneity
among their patients [10, 11]. A simple question rises; which
anthropometric measurements may be useful and effective
to screen for the central obesity type of body fat of patients
with elevated blood pressure and fasting plasma glucose in
primary care practice? It has been recommended that every
population should determine their best anthropometric
measurement tool(s) in order to screen general and visceral
adiposity [1, 5]. We are not aware of any previous reports in
Nigeria in which data regarding the important relationship
Akamo, et al.: Anthropometry, type 2 diabetes, hypertension, obes
J Invest Biochem ? 2015 ? Vol 4 ? Issue 2 51
between general obesity and central obesity, and their
correlation with known CVD risk factors are investigated.
Thus, this study aimed to compare anthropometric
measurements of general obesity body mass index (BMI),
body fat percentage (BF %)] and central obesity [umblical
circumference (UC), waist circumference (WC), hip
circumference (HC), waist-to-hip ratio (WHR) and waist-toheight ratio (WHtR)] and assess the respective associations
with type 2 diabetes, hypertension and their comorbidity,
and also to determine if the association between the
anthropometric indices and cardiovascular risk factors varies
with gender.
Introduction: Diabetes mellitus is a complex metabolic disorder associated with chronic hyperglycaemia and hyperglucosuria
arising from insulin deficiency. It is accompanied by dyslipidemia, a major risk factor contributing to
cardiovascular diseases. Therefore, the effects of omega-3 fatty acid (O3FA) supplement on plasma, erythrocyte and
lipoproteins lipid profiles as well as aryl esterase activities in plasma and the lipoproteins of alloxan-induced (150
mg/kg body weight (b.wt), intraperitoneally) diabetic male rats were investigated. O3FA (0.4 g/kg b.wt/day) was
administered as pre- and post- treatment for 2 weeks. The blood parameters were measured spectrophotometrically.
The lipid levels were significantly increased (p<0.05) in the various compartments of the diabetic rats. The increase
was from 30% - 107% for cholesterol, 20% - 52% for phospholipid and 38% - 111% for triacylglycerol. Lipid
peroxidation was also increased from 67% in extracellular fluid to 164% in the high density lipoprotein (HDL)
compartment. O3FA administration significantly reduced (p<0.05) the levels of cholesterol, phospholipid and
triacylglycerol by varying extents in the various compartments while increasing cholesterol and phospholipid levels
in HDL. Lipid peroxidation was significantly reduced (p<0.05) by O3FA suggesting that it has protective effect
against oxidative damage. Aryl esterase activities in the lipoproteins were also activated by supplementation with
O3FA (except in HDL pre-treatment). This study indicates that O3FA supplement attenuates dyslipidemia
associated with diabetes mellitus and should be included in diets for prevention and treatment of diabetes mellitus.
Introduction: ABO blood groups, Rhesus factors and haemoglobin genotypes are all inherited blood characters.
This this study was aimed at investigating the relative incidence of hypertension comorbidly occurring with type 2
diabetes mellitus (T2DM) in ABO/Rhesus blood groups and haemoglobin genotypes in some residents of Abeokuta,
South-Western Nigeria. Age and sex matched control subjects (n=150) and patients (n=470) [hypertensive nondiabetics (HND, n=179), normotensive diabetics (ND, n=132), hypertensive diabetics (HD, n=159)] presenting at the
Medical Out-Patient Clinic of the State Hospital, Abeokuta, Nigeria were recruited. Standard electrophoretic and
haemagglutination techniques were employed in testing the blood samples. Fasting plasma glucose, haemoglobin,
plasma creatinine and plasma urea were determined spectrophotometrically. Blood pressure and its component were
also determined. Prevalence of hypertension and/or T2DM was observed in subjects with blood O followed by A.
The phenotype frequencies of ABO blood group in both hypertensive and diabetic patients and controls (both sexes)
are in the order O>A>B>AB. The RhD+ and RhD- distribution were similar in patients and their control counterparts
(p > 0.05). The spectrum of haemoglobin electrophoresis among the controls and patients can be shown with a
general formula HbAA>HbAS>HbAC>HbSS>HbSC>HbCC except in control female and HD female. The results
obtained suggest that there is a strong positive relationship between blood group O and hypertension and/or T2DM.
Large studies in other ethnic groups are needed to confirm these results.
Introduction: To investigate the comparative effects of ascorbate and chelating agents on some markers of lipid metabolism in lead exposed rats, 35 male Wistar rats were used. They were grouped randomly into five (n=7); 28 of which were administered 75 mg/kg body weight lead acetate (PbAc) orally for 14 days after which their blood samples were assayed for lead. Three of the groups were further administered 30 mg/kg body weight D-penicillamine (D-pen), 30 mg/kg body weight succimer (DMSA) and 500 mg/kg body weight ascorbate (Asc) daily orally, respectively. The control group was however administered normal saline. The blood lipid profiles were determined spectrophotometrically. Lead exposure resulted in significant dyslipidemia (p < 0.05), characterized by 50% hypercholesterolemia and hypertriglyceridemia and 132% hyperphospholipidemia (plasma) while in the red blood cells, hypocholesterolemia and hypophospholipidemia were observed. During the therapeutic doses, the groups administered chelating agents and Asc showed a significant amelioration in the plasma and red blood cell levels of total cholesterol, triacylglycerols and phospholipids in the order, DMSA > Asc > D-pen. Decrease in blood lead levels after therapy indicated that the chelating agents have an advantage over Asc. The study indicates that administration of the antioxidant, Asc may not be more efficacious than the chelating agents but could be a cheaper and more convenient therapy for lead toxicity.
Introduction: Diabetes Mellitus is one of the heterogeneous metabolic disorders associated with dyslipidemia, a major risk factor
contributing to cardiovascular disease. This metabolic abnormality affects virtually all organs. Over the years,
antidiabetic drugs which majorly aim at the hyperglycemic aspect of the disease have been used. Therefore, to
address this dyslipidemia, omega-3 fatty acid (O3FA) supplement was employed. Its effects on lipid metabolism in
the organs (heart, liver, kidney, pancreas, spleen and brain) of alloxan-induced (150mg/kg body weight,
intraperitoneally) diabetic male rats were investigated. O3FA (0.4g/kg b.wt/day) was administered as pre- and posttreatment for 2 weeks. The lipid levels were significantly increased (p<0.05) in diabetic rats. O3FA administration
significantly reduced (p<0.05) the levels of cholesterol, phospholipids, triacylglycerol by varying extents, in the
examined organs without affecting hyperglycemia in the diabetic rats. The ratio of HMG CoA/mevalonate decreased
in the liver of the diabetic rats by 28% indicating increased activity of HMG-CoA reductase. This diabetes-induced
dyslipidemia was accompanied by a 28% increase in the activity of hepatic HMG-CoA reductase. Administration of
O3FA to the diabetic rats however resulted in 10% and 17% decrease in the activity of this enzyme in the pre- and
post-treated groups respectively. Also, lipid peroxidation was significantly reduced (p<0.05) by O3FA suggesting
that it has protective effect against oxidative damage. This study reveals that O3FAsupplement has beneficial effects
in attenuating dyslipidemia observed in diabetes mellitus and could be beneficial as an adjunct in the management
of diabetes mellitus
Introduction: Plasma lipid profile, atherogenic and coronary risk indices in some residents of Abeokuta in south-western Nigeria.
Introduction: In order to investigate the toxic effects of lead during occupational exposure to this metal, the activity of aminolevulinic acid dehydratase (ALAD) and the concentrations of erythrocyte protoporphyrin (EPP) were determined in blood of various artisans in Abeokuta, Nigeria and these were related to blood lead levels. ALAD activity in the artisans was inhibited to varying extents. ALAD activity was inhibited to the tune of 77% in petrol station attendants while the lowest inhibition of 36% was obtained in the welders. EPP was also significantly increased in the artisans (p < 0.001). The highest EPP level of 241.57 ± 89.27 ?g/100 ml of red blood cell was observed in upholsterers. A significant (p < 0.001) negative correlation was observed between ALAD activity and blood lead levels on one hand (r = ?0.631) and between ALAD activity and EPP on the other hand (r = ?0.461). Administration of a daily dose of 500 mg ascorbic acid for 2 weeks reversed the lead-induced inhibition of ALAD. Increased EPP levels observed in the artisans also responded positively to the ascorbic acid supplementation. A significant reduction (p < 0.001) in blood lead was also observed in the artisans at the end of the 2-week ascorbic acid therapy. Our findings indicate that ascorbic acid may offer more advantages over the conventional agents for the treatment of lead poisoning, especially in cases where the subjects cannot be removed from the source of lead exposure.
Introduction: In order to investigate the effects of lead exposure on risk of cardiovascular disease during occupational exposure to this metal, plasma cholesterol and its fractions as high-density liporotein (HDL), low-density liporotein (LDL) and triglyceride were determined in various artisans in Abeokuta, Nigeria who have been shown to be occupationally exposed to lead and these were related to blood lead levels. Increased risk of cardiovascular disease was observed in the artisans. Total cholesterol in the artisans was between 1.5 and 2.0 times higher in the artisans than that present in controls while LDL cholesterol was between 1.6 and 2.4 times higher in the artisans when compared with control subjects [p < 0.001]. HDL cholesterol and triglyceride levels were not affected [p > 0.05]. A significant positive correlation was observed between blood lead and total cholesterol on one hand [r = 0.372; p = 3.0 × 10-5] and blood lead and LDL cholesterol on the other hand [r = 0.283; p = 0.001]. LDL/HDL cholesterol ratio was also higher in the artisans when compared with control. Blood pressure (systolic and diastolic) and other anthropometric parameters were not significantly different between the artisans and the control subjects [p > 0.05]. Results suggest that lead exposure increases cholesterol synthesis and transport to peripheral tissues whereas reverse cholesterol transport to the liver is not affected.
Introduction: Effects of 2-week vitamin C supplementation in occupationally lead exposed artisans from a mechanic village in Abeokuta, Nigeria.
Introduction: The effects of soybean (Glycine max. Merr.) condiment on food intake and some physiological parameters.
Introduction: The development of new biofortified cassava cultivars, with higher micronutrient contents, offers great potential to enhance food and nutrition security prospects. Among the various constraints affecting cassava production are plant parasitic nematodes (PPN), especially root-knot nematodes. In this study, six popular biofortified cultivars were field-evaluated for their response to PPN in Nigeria. A field naturally infested with a diversity of PPN but dominated by root-knot nematodes was used. Application of the nematicide carbofuran significantly reduced PPN densities, and at harvest, no root galling damage was observed, compared with untreated plots, which had heavy galling damage. Plant height, stem girth, plant weight, marketable storage root number and weight were significantly lower for most cultivars in untreated plots. Percentage yield losses in the range of 21.3–63.7% were recorded from two separate trials conducted for 12 months each. Lower total carotenoid and dry matter contents were associated with higher PPN densities in some biofortified cultivars, resulting in a loss of as much as 63% of total carotenoid and 52% of dry matter contents. The number and weight of rotted storage roots were significantly greater in untreated plots across cultivars, reducing in-field and post-harvest storability. This study demonstrates that natural field populations of PPN can substantially affect yield, quality and nutritional value of released biofortified cassava cultivars
Introduction: Despite being the single largest cassava-producing country, yields in Nigeria remain consistently poor and among the lowest. Regionally, yields are also particularly low across Africa. Pests and pathogens, including plant-parasitic nematodes, play an important role in this current yield deficit. African countries are not only faced with the problem of food security but also that of nutritional deficiency, due to limited micronutrients in the diet. In this study, six biofortified cultivars were evaluated for their response to inoculation with approximately 30?000 root-knot nematode (Meloidogyne incognita) eggs in 30 l pots in Nigeria. All cassava cultivars proved highly susceptible to M. incognita infection after 6 months, with nematode reproduction factor ranging from 7.0 to 44.8. Galling was common on feeder roots and gall index scores were recorded between 4 to 5 (on a scale of 1-5 where 5 ? 100 galls). Meloidogyne incognita infection significantly reduced plant height, stem girth, fresh plant mass, fresh storage root number and storage root weight. Percentage yield loss of between 41.8-88.4% was recorded in M. incognita-infected plants compared with non-infected controls. Although M. incognita reduced storage root weight, it did not necessarily affect the nutritional quality (total carotenoid) or dry weight percentage of the biofortified cassava cultivars. Total carotenoid and dry weight contents of the control cultivar were similar to some of the biofortified cultivars. The high susceptibility of the biofortified cassava cultivars to M. incognita infection indicates that substantial yield losses are likely being experienced by farmers, as this nematode pest is prevalent across sub-Saharan Africa and the tropics.
Introduction: In this study, seven cassava varieties were evaluated for their response to infection by Meloidogyne
incognita in a pot experiment using 30-liter plastic pots. The cassava varieties - TMS 98/0505, TMS
01/1368, TMS 98/0510, TMS 30572, TME EB419, TMS 95/0289, and TMS 98/0581 were inoculated with
either 30,000 or 0 eggs of M. incognita in a 7 x 2 factorial experiment and grown for 6 months in sterilized
soil in a randomized complete block design with three replicates. Data were collected on plant height, stem
girth, number and weight of root tubers, number of galls on feeder roots and tubers, number of juveniles
per gram feeder roots, and foliage weight. Root systems were scored for galling on 1-5 rating scale.
Assessment of plant tolerance to the root-knot nematode was based on gall index (GI) and tuber yield.
Assessment of plant resistance to the root-knot nematode was based on nematode reproduction factor (RF).
Galls were found on feeder roots and storage roots of infected cassava plants. Gall indices varied from 3
to 5 for infected roots. TME EB419 was tolerant to M. incognita with average tuber yield of 425 and 352
g/plant for inoculated and nematode-free cassava plants respectively, GI of 3.0 and an R of 2.6. Six of the
cassava varieties were susceptible and intolerant to M. incognita with RF between 1.2 and 6.0, GI ranging
between 4 and 5, and significant yield loss (P<0.05). Nematode infection (P<0.05) reduced plant height
and fresh tuber weight in the cassava varieties except for the tolerant TME EB419 variety.
Introduction: Cassava (Manihot esculenta Crantz) has seldom received attention by nematologists because of the erroneous belief that it was too hardy to be significantly damaged by nematodes. In this study, cassava varieties (TMS 98/0505, TMS 01/1368, TMS 98/0510, TMS 30572, TME EB419, TMS 95/0289, and TMS 98/0581) from the International Institute of Tropical Agriculture were evaluated for their field response to infection by Meloidogyne incognita and 10 other plant-parasitic nematodes (PPN) at the Federal University of Agriculture, Abeokuta. Cassava growth and yield were compared in naturally infested PPN plots treated with and without carbofuran (3 kg a.i./ha). Aphelenchoides, Tylenchus, Longidorus, Pratylenchus, Hoplolaimus, Rotylenchus, Helicotylenchus, Trichodorus, Xiphinema, Meloidogyne, and Scutellonema were identified in the soil. Infected plants were scored for galling (as a result of Meloidogyne infection only) on 1-5 rating scale. Carbofuran-treated plots had significantly (P? 0.01) lower final densities of Meloidogyne and other PPN, and no galls were observed on feeder roots. The majority of crop growth and yield improved in plots treated with carbofuran. Significantly fewer storage roots rotted, and yield of all the cassava varieties was significantly higher (4.05-6.10 kg/plot) in carbofuran-treated plots compared to untreated plots (2.33-4.95 kg/plot). The average tuber yield of the carbofuran-treated and untreated plots was 51.3 and 34.1 T/ha, respectively, and the difference was significant across varieties (TMS 01/1368 and TMS 30572). This work suggests that cassava production can be improved by controlling nematodes in the field.
Introduction: Annals Food Science and Technology 15(1): 121- 134.
Introduction: Phytate is an anti-nutritional agent in cereal foods, making nutritional and health problems in human. The gene responsible for the degradation of phytate has been identified in many bacterial species but not in lactic acid bacteria. The objective of this study was to isolate and characterize phy gene in lactic acid bacteria isolated from Ogi and Kunun-zaki.
Introduction: In Nigeria, pharmaceutical wastewaters are routinely disseminated in river waters; this could be associated with public health risk to humans and animals. In this study, we characterized antibiotic resistant bacteria (ARB) and their antibiotic resistance profile as well as screening for sul1 and sul2 genes in pharmaceutical wastewater effluents. Bacterial composition of the wastewater sources was isolated on non-selective media and characterized by the polymerase chain reaction (PCR) amplification of the 16S rRNA genes, with subsequent grouping using restriction fragment length polymorphism (RFLP) and sequencing. The antibiotics sensitivity profiles were investigated using the standard disk diffusion plate method and the minimum inhibitory concentrations (MICs) of selected antibiotics on the bacterial isolates. A total of 254 bacterial strains were isolated, and majority of the isolates were identified as Acinetobacter sp., Klebsiella pneumonia, Proteus mirabilis, Enterobacter sp. and Bacillus sp. A total of 218 (85.8%) of the bacterial isolates were multidrug resistant. High MICs values were observed for all antibiotics used in the study. The result showed that 31.7%, 21.7% and 43.3% of the bacterial isolates harbored sul1, sul2, and Intl1 genes, respectively. Pharmaceuticals wastewaters are potential reservoirs of ARBs which may harbor resistance genes with possible risk to public health.
Introduction: Forge materials were combined to make silage and an in vitro digestion of the
silage was carried out to evaluate their effects on bacterial population. Ensiled Guinea
grass (Panicum maximum) together with Albizia saman pods samples were collected at
42 day post fermentation. A total of 40 isolates of lactic acid bacteria were identified
from the fermented core of the silage. The Lactic Acid Bacteria (LAB) isolates were
subjected to various pH and temperatures. Production of lactic acid by the LAB was
also determined. . From the in vitro fermentation, 25 bacteria were isolated from the
digest. The isolates of the LAB belong to the genera Lactobacillus. They were identified
as Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus buchneri, Lactobacillus
coryniformis and five were Lactobacillus species that were not identified to their
species level. The rumen bacteria isolates other than LAB included the genera
Citrobacter, Alcaligenes, Pseudomonas, Enterobacter, Proteus, Escherichia coli,
Serratia and eight were unidentified. During the in vitro digestion of the ensiled sample,
the rumen bacteria population increased between the hours of 18 and 36. Most of the
isolates had their optimum growth between pH 4.5 and 6.0 and temperature between
250
C and 400
C. The isolates Lactobacillus plantarum SL25 and the unidentified SL16
had the highest lactic acid production at 31.53g/l. Lactobacillus plantarum SL34 had
the lowest production of lactic acid at 11.72g/l. To control the ensiling process, improve
quality and to inhibit unwanted microorganisms, LAB can be used as an additive and
the ensiling conditions could be manipulated.
Introduction: This study reports the prevalence of typhoid fever caused by Salmonella typhi between genders. It further establishes the Salmonella titres that are not diagnostically significant but normal in the study population and the titre that could be used as presumptively diagnostic of typhoid fever. Blood samples were collected from 200 subjects; 82 males and 118 females; and examined for the presence and levels of Salmonella antibodies by Widal agglutination technique. Standard S. typhi and Salmonella paratyphi "O" and "H" suspension (ANTEC) were used as antigens. Of the 200 sera tested, agglutinins to S. typhi were most prevalent in male subjects accounting for 39% of the "O" antigens and 41.5% of "H" antigens at the various dilutions while in the 118 female subjects, 10.7% accounts for the "O" and 29.5% for the "H" antigens. There was a male preponderance (M/F 2:1). Since the positive sera with titres of ? ? ? ? 80 occurred in more than 5% of the samples, this study therefore suggests that such titres be regarded as normal among the communities studied while there should be a high index of suspicion of clinical infections in titres above 80 when a second serum is impractical. This will improve accurate diagnosis. Improving accurate diagnosis is the surest way to reverse the deteriorating health status of Nigerians. INTRODUCTION Salmonella typhi is a bacterium that causes typhoid fever (enteric fever). Typhoid fever is an acute, life-threatening febrile illness caused by the bacterium Salmonella enterica serotype Typhi (CDC, 2008). Typhoid fever is a global infection with a fatality rate of 10%. The disease is a cause for concern and a major public health problem in developing countries (Asia, Africa), especially in Nigeria due to poor sanitary conditions and lack of or inadequate potable water (Anita et al., 2002; Doughari, 2005). The World Health Organization (WHO) estimated an annual infectious rate of 21.6 million and approximate death rate of 600 000 with the highest percentage in Africa and Asia. (WHO, 2008). Typhoid (enteric) fever caused by S. typhi is an endemic disease in the tropic and sub-tropic and has become a major public health problem in developing countries of the world with an estimated annual incidence of 540 per 100,000. It is often encountered in tropical countries including Nigeria where they constitute serious sources of morbidities and mortalities. It is caused by S. typhi. Gram negative bacteria which are motile, though non-flagellate variants occur. Capsules are not formed. They are intestinal pathogens which comprises a species S. typhi which causes an enteric fever known as typhoid fever (Philip, 2000). S. typhi has somatic antigens and glycolipid microcapsule the VI or virulence antigen. Phage typing can distinguish different strains of the organism. Enteric fever caused by S. typhi is often
Introduction: This study examines and reports the prevalence of plasmodium species between gender of freshmen (first year
students) of Nnamdi Azikwe University, Akwa, South-Eastern, Nigeria. Blood film examination for malaria parasites in
200 (100.0%) freshmen; 82 (41.0%) males and 118 (59.0%) females was carried out over a 6-month period. Microscopic
examinations of both thick and thin blood films techniques were employed for this study. A high malaria parasite
prevalence rate of 80% was noted in these subjects. Of the 200 samples examined, 160 (80.0%) were Plasmodiumpositive. There was a female preponderance (F/M 2:1). A higher Plasmodium prevalence was recorded amongst
females 102 (86.4%) than in the males 58 (70.7%) and there was no significant increase in malaria infection rate in any
particular sex (P=0.05). Plasmodium falciparum was the most prevalent of all the other species. This study also shows
that a good percentage of people were infested by malaria with P. falciparum [134 (83.8%)] being the most prevalent
species, followed by P. malariae [14 (8.9%)], P. vivax [8 (5.0%)] and P. ovale [4 (2.5%)]. P. ovale was only found among
the female subjects and none was found among the male subjects. The findings of this study are of a practical impact,
with female subjects having the highest proportion of parasitic contamination. The higher prevalence of malaria
Plasmodium found in this study could be attributed to the stagnant drainage systems in the University, which created
favorable environmental conditions for the breeding of mosquitoes that act as vectors of malaria parasites and so this
enhances the proliferation of the Plasmodium. It could also be attributed to the effect of climatic features on vector
breeding and transmission. Wet season usually promote mosquito breeding. Also, the prevalence of P. falciparum could
be attributed to its ability to resist attack of most drugs that are commonly in use in the study area. However, there
should be a high index for the needs to take appropriate measures aimed at preventing malaria by intensifying efforts in
mosquitoes eradication program through operation roll back malaria in Africa, especially in Nigeria.
Introduction: This study examines and reports the prevalence of plasmodium species between gender of freshmen (first year
students) of Nnamdi Azikwe University, Akwa, South-Eastern, Nigeria. Blood film examination for malaria parasites in
200 (100.0%) freshmen; 82 (41.0%) males and 118 (59.0%) females was carried out over a 6-month period. Microscopic
examinations of both thick and thin blood films techniques were employed for this study. A high malaria parasite
prevalence rate of 80% was noted in these subjects. Of the 200 samples examined, 160 (80.0%) were Plasmodiumpositive. There was a female preponderance (F/M 2:1). A higher Plasmodium prevalence was recorded amongst
females 102 (86.4%) than in the males 58 (70.7%) and there was no significant increase in malaria infection rate in any
particular sex (P=0.05). Plasmodium falciparum was the most prevalent of all the other species. This study also shows
that a good percentage of people were infested by malaria with P. falciparum [134 (83.8%)] being the most prevalent
species, followed by P. malariae [14 (8.9%)], P. vivax [8 (5.0%)] and P. ovale [4 (2.5%)]. P. ovale was only found among
the female subjects and none was found among the male subjects. The findings of this study are of a practical impact,
with female subjects having the highest proportion of parasitic contamination. The higher prevalence of malaria
Plasmodium found in this study could be attributed to the stagnant drainage systems in the University, which created
favorable environmental conditions for the breeding of mosquitoes that act as vectors of malaria parasites and so this
enhances the proliferation of the Plasmodium. It could also be attributed to the effect of climatic features on vector
breeding and transmission. Wet season usually promote mosquito breeding. Also, the prevalence of P. falciparum could
be attributed to its ability to resist attack of most drugs that are commonly in use in the study area. However, there
should be a high index for the needs to take appropriate measures aimed at preventing malaria by intensifying efforts in
mosquitoes eradication program through operation roll back malaria in Africa, especially in Nigeria.
Introduction: The realisations of joke performances are subtly and richly encrusted in linguistic and discourse strategies. In a multilingual setting, stand-up comedians need to negotiate the linguistic code(s) to convey their jokes. This study analyses how Nigerian stand-up comedians negotiate codes and voice within the performance space. Although studies have identified the use of code alternation in stand-up performances, the pragmatic and performance functions of code selection in Nigerian stand-up comedy have not been examined. This study, therefore, attempts to fill this vacuum by analysing code switching, selection and voice alternation in purposively selected routines of four Nigerian stand-up comedians. Inputs from functional approaches to code switching and code selection, the concept of voice, and the notions of context and contextualisation are key to this study. Nigerian stand-up comedians adopt two contexts: context-of-the-joke and context-in-the-joke, which are synchronous with the primary and secondary narrative levels in the performances. Selecting and alternating codes within a routine is a strategy which indicates who speaks in the narration of jokes.
Introduction: The realisations of joke performances are subtly and richly encrusted in linguistic and discourse strategies. In a multilingual setting, stand-up comedians need to negotiate the linguistic code(s) to convey their jokes. This study analyses how Nigerian stand-up comedians negotiate codes and voice within the performance space. Although studies have identified the use of code alternation in stand-up performances, the pragmatic and performance functions of code selection in Nigerian stand-up comedy have not been examined. This study, therefore, attempts to fill this vacuum by analysing code switching, selection and voice alternation in purposively selected routines of four Nigerian stand-up comedians. Inputs from functional approaches to code switching and code selection, the concept of voice, and the notions of context and contextualisation are key to this study. Nigerian stand-up comedians adopt two contexts: context-of-the-joke and context-in-the-joke, which are synchronous with the primary and secondary narrative levels in the performances. Selecting and alternating codes within a routine is a strategy which indicates who speaks in the narration of jokes.
Introduction: As the subject of fatherhood continues to receive scholarly attention in the twenty-first century, evidenced by the mounting weight of academic discourse on the subject; it also becomes more appealing to contemplate how literature contributes to the discourse of the father through the genre of the novel. Terry Eagleton succinctly observes that all literary texts contain one or more sub-texts, and that there is a sense in which they may be spoken of as the “unconscious” of the work itself (155). By examining the emasculated father (due to racism) and his complement, the commodified father (as a result of slavery) in the selected narratives, Morrison’s imaginative vision of the enfeebled father is brought to the fore. Although Beloved and The Bluest Eye have been examined mostly as Sethe’s and Pecola’s stories respectively, they are read here as sub-texts of fatherhood. Therefore, by exploring the key father characters in these texts and employing Carl Jung’s psychoanalytical concept of Individuation and R.W Connell’s Marginalised masculinity as analytical tools, the paper delves into some of the challenges that confront father characters and how they respond to these challenges which, ultimately, engender their statuses as emasculated and commodified fathers. This paper thus, examines the resultant ruptures in the psyches of the father characters which may have triggered the crisis that precludes their uncomplicated transition from boys and men to husbands and fathers. The paper concludes that the characters’ failure to achieve individuation is significantly implicated in their status as enfeebled fathers in the two narratives.
Introduction: While George Lamming portrays paternal identity, alienation and exile as
thematic preoccupations of In the Castle of my Skin and Season of Adventure,
father absence remains a major concern in his artistic depictions of fatherhood in
these narratives. The phenomenon of father absence creates a void which the
mother must additionally fill, and the presence of this void provokes as well as
fosters androgyny. Androgyny is the state of having traits of both genders and
refers to the opposites within. Thus, the two texts bring the notion of the synthesis
of the masculine and feminine principles in the human psyche fully to the fore.
The key mother characters in both novels exhibit the image of Carl Jungs
Father Archetype which is categorised as stern, powerful and controlling.
Reading these mother characters as female fathers forces the attention from
them as women and mothers, hence, radically unsettling the conventional notion
of who a father is. Using Jungs psychoanalytic concept of anima/animus as
framing and analytical tools, this paper challenges the stereotypical portrait of
the hegemonic male parent and furnishes an option for a re-envisioning of
masculinity and fatherhood in the context of parental authority, role performance
and conduct. It construes, arguably, that the abilities of the mother characters to
bear and rear children, cross gender role boundaries and compensate for their
offspring's absent fathers, are irrefutable. In this way, both novels do not just
recommend themselves as masculinist texts, but they also show how the mother
characters qualify as fathers, albeit, female fathers.
Introduction: The undercurrents of the inferior female and the marginalised mother which are considerably discernible in Oil Man of Obange and Purple Hibiscus alert the reader to the complex and, often, objectionable practices which continue to sustain patriarchal ideologies and encourage their related female-suffocating philosophies to thrive within a typical family unit. The expression, "female-suffocation" as deployed in this paper refers to the stifling of female productivity, talents and creative energies which, predictably, result when females attempt strict conformity to patriarchal ideals of normative femininity. Drawing on the conceptual framework of the theory of feminism as espoused by Akachi Ezeigbo, this chapter argues that while the two main mother characters in the selected texts are maginalised by the general patriarchal system of their individual environments, however, they fail to utilise the necessary emancipation tools of sensitiveness, wisdom, self-improvement and resilience. Therefore, by wholly accepting the socio-familial constructions of femaleness which devalue them, they unwittingly or otherwise, encourage their husbands' unrestrained hegemonic stance. In this manner, the characters yield to self-tyranny and ultimately become both the victimisers and the victimised. Consequently, they do not only promote and prolong the legacy of gender inequality but also remain complicit in their own devaluations, indignities and afflictions.
Introduction: The Pilgrim Unbound.” Wreaths for a Wayfarer: An Anthology of Poems in Honour of Pius Adesanmi, Eds. Nduka Otiono and Uchechukwu Umezurike.
Introduction: This article explores the comedic construction of national identity in Nigerian stand-up comedy. By national identity, I mean collective perspectives on the sociopolitical and cultural realities of postcolonial Nigeria. While critical discourse analysis provided the framework for interpretation, data was derived from purposively sampled recorded videos of Nigerian stand-up comedians. Such collective perspectives are constructed when a comedian indexes cultural/political events and situations in a monologue. The investigation reveals four identity mapping strategies: performing (non)theatrical identities, using the comedy voice to indicate multiple identities, constructing a trickster identity and constructing a resilient spirit identity. These strategies entail foregrounding assumptions about the Nigerian state and using language in a strategic way to indicate sociopolitical and cultural realities.
Introduction: This essay examines the manner in which Nigerian stand-up comedians evoke gendered concepts in their routines. Specifically, it analyses how gender is manifested and enacted in linguistic expressions, which literally do not have gender undertones. Three strategies for instantiating such gendered conceptualization are identified, privatization of meaning through lexical contextual adjustment, creating ad hoc conceptual coherence in the monologues and foregrounding pragmatic presuppositions on ge
Introduction: The bond between language and ideology has caught the attention of discourse analysts.
Investigating this bond, discourse analysts have further demonstrated that everyday interactions
are embedded in and with different ideologies. Likewise, the performance of humour is motivated by the interlocutors’ ideological inclinations. On the strength of these propositions, this
study attempts a critical analysis of the ideologies in selected Nigerian stand-up comedy routines (NSC), with particular reference to Fairclough and Wodak’s notions of ideology in discourse. Routines were purposively selected from editions of “Night of a Thousand Laughs”
(NTL), the earliest stand-up event and a stand-up comedy road show in Nigeria, so as to focus
on the performances of practicing and professional stand-up comedians in the country. Two
categories of ideologies were found in NSC routines: the first relates to the art of comedy performance while the second relates to the country’s sociocultural context. In the first category,
the comedians project stand-up comedy as a “dignified” profession, while in the second, they
draw from sociocultural beliefs in order to project their ideologies about gender, ethnicity and
the political class.
Introduction: Studies on stand-up comedy and jokes have noted that context plays a major role in the generation and interpretation of jokes and humorous routines. However, these studies do not formalize the concept and what constitute it in joke exchanges. Focusing on Nigerian stand-up comedy, this study is aimed at conceptualizing and describing the contexts that could be found in joking exchanges. The study proposes two types: context-of-the-joke and context-in-the-joke. The context-of-the-joke is grounded in shared beliefs that exist between the participants-of-the-joke. The context-in-the-joke is characterized by features such as joke utterance, participants-in-the-joke (most especially the target) and activity-in-the-joke among others. These features make up the contextualization cues that the participants-of-the-joke (both the joke teller and recipient) use in joke generation and interpretation.
Introduction: Abstract In interactions, the culture of the participants influences their contributions and interpretations. Stand-up comedians articulate contemporary culture by making mutually manifest cultural beliefs and representations within the performance space, and teach the audience how to use them. This paper investigated how Nigerian stand-up comedians employ cultural assumptions and representations in their performances. Using relevance theory for analysis and seven routines from seven Nigerian stand-up comedians as the data, this study explored how Nigerian stand-up comedians bring shared cultural knowledge into their performances. Nigerian stand-up comedians joke with culture by manipulating shared cultural representations, distorting collective knowledge, manipulating stereotypes and projecting personal beliefs. By joking with cultural beliefs and representations within the performance space, Nigerian stand-up comedians mediate and negotiate what “contemporary culture” should be.
Introduction: In Nigeria, in relation to the aforesaid functions, everyday citizens and professional humourists use humour to express their expectations from and disappointments in the socio-political leadership of the country. Common Nigerian jokes indicate the country’s travails with ethnicity and failed political leadership. They also enunciate populist perspectives on nationhood, identity and the challenges of everyday living. In spite of the centrality of humour to daily life in Nigeria, scholarly interests in its sociocultural, political, rhetorical, interactional and interpersonal dimensions have been very minimal. According to Obadare (2016), it is as if once something is categorised as humour, it is expunged from any serious interrogations. There are diverse and numerous dimensions of humour in Nigeria, given the country’s extensive and still expanding popular culture landscape. A handful of these dimensions are examined in the papers that make up this special issue of EJHR.
Introduction: Studies on humour have acknowledged that responses to jokes are important aspects of a
joking exchange; however, investigation of joke recipients’ responses has received little
attention from humour scholars. Moreover, the linguistic investigations of jokes have been
limited to native speakers’ contexts, leaving ESL contexts out. Therefore, this study examines
readers’ responses to a genre of jokes in Nigerian online spheres, Akpos jokes, with a view to
characterising their forms and functions. Akpos jokes are humorous narratives created
around an imaginary character called Akpos. Jokes are randomly collected from a blog and
readers’ responses were derived from a Facebook page in which Akpos jokes are published.
Using computer paralanguage and language mixing in writing the jokes and the responses,
the jokes and the reactions to them mirror the online and the Nigerian ESL contexts in which
they are situated. Readers use their responses to indicate affiliation, disaffiliation with the
joke, or to introduce something that has nothing to do with the subject of the joke or humour.
Readers also use their responses to argue for and/or against the humorousness the jokes.
Introduction: The main objective of this article was to identify and analyse humorous strategies found in Nigerian stand-up comedy. Particularly, the illustrations were taken from the routines of a popular Nigerian stand-up comedian, I Go Dye. First of all, a case was made for humorous meanings. How humorous meanings were achieved in stand-up comedy performance was then explained. Analysis showed that I Go Dye, as a Nigerian stand-up comedian, adopted exaggeration, naming and labelling, self-praising, self-denigrating and retorts as strategies for expressing humorous meanings.
Introduction: The aim of this paper is to characterise stand-up performance as an activity type and
explore ways through which the participants in a stand-up comedy performance,
especially the stand-up comedians, manipulate the parameters of an activity type so as
to achieve their interactional goals. Data comprised extracts from routines of randomly
selected six Nigerian stand-up comedians in a recorded video. Analysed routines
indicated that the participants’ goal and institutional identities influenced how they
manipulated the parameters like allowable contribution and interpersonal maxims; for
instance, the audience made use heckling to negotiate allowable contribution so as to
indicate that their interactional goal was unfulfilled while stand-up comedians made use
self-denigrating motif so as to elicit laughter and reduce the interactional distance
between themselves and the audience.
Introduction: The goal of this study is to analyse the use of mimicry in Nigerian stand-up comedy. Mimicry is conceived as a strategy in the routines of Nigerian stand-up comedians, who adopt two kinds of mimicry acts: verbal and nonverbal. For comedians to use mimicry, they have to draw from collective beliefs they share with their audience. On their part, the audience find a mimicry act humorous because it relates to their background assumptions. Data for analysis comprised four routines of four Nigerian stand-up comedians purposively selected because of the comics’ extensive use of mimicry. Mimicry activates background assumptions, distorts the collective representation of the target and could be used for articulating voice in stand-up performances.
Introduction: The concept of name and naming is not just a tool for constructing identity; it is an important signification system in African cosmology. It is imbued with the people's perception of life and being. This explains why certain individuals who are discontented with their names either change them or adopt nicknames to reflect their sense of dignity, reinvented individuality and humanity. This paper explored nicknaming as a signification tool for identity reinvention from a socio-semiotic dimension. Data for the study was sampled purposively from students' halls of residence at the University of Ibadan and analysed using insights from socio-semiotic theory of sign. The use of irony in names was observed to be a common tool for reinvention, especially with those instances where the nicknames were given as derogatory labels to redesign the identities of the concerned personalities. It was observed also that others use nicknames to project a sense of reinvented self, especially in instances where the nicknames were the creations of the individuals concerned.
Introduction: The primary focus of this paper is to apply Discourse Type theory to stand-up comedy. To
achieve this, the study postulates two contexts in stand-up joking stories: context of the joke
and context in the joke. The context of the joke, which is inflexible, embodies the collective
beliefs of stand-up comedians and their audience, while the context in the joke, which is
dynamic, is manifested by joking stories and it is made up of the joke utterance, participants in
the joke and activity/situation in the joke. In any routine, the context of the joke interacts with
the context in the joke and vice versa. For analytical purpose, the study derives data from the
routines of male and female Nigerian stand-up comedians. The analysis reveals that stand-up
comedians perform discourse types, which are specific communicative acts in the context of
the joke, such as greeting/salutation, reporting and informing, which bifurcates into self-praising and self denigrating.
Introduction: Rivalry and enmity are phenomena that seem to have permeated the Nigerian music industry, especially the hip hop genre. In this regard, Nigerian hip hop artistes employ language to demonstrate their superiority over one another. A strategy employed by Nigerian hip hop artistes to assert their differences and superiority is the pragmatic use of pronouns. Here, pronouns are said to do more than achieve coherence.The paper investigates how Nigerian hiphop artistes use pronouns to achieve pragmatic meanings. Nigerian hip hop artistes employ pronouns to project their individuality and personality; identify and solidarise with their fans, and map boundary and polarity with their rivals. The paper submits that, while using pronouns, the Nigerian hip hop artistes express a sense of rivalry and enmity, individuality and personality; identity and solidarity.
Introduction: The bacteriological examination of chronic osteomyelitis cases in Ile-Ife, revealed Proteus mirabilis as the predominant isolate encountered (23.1%). Staphylococci constituted 30.7% of the total bacterial isolates with Staphylococcus aureus accounting for only 10.2%. Other Gram-positive cocci cultured include, Staphylococcus spp (20.5%), coagulase negative staphylococci (CONS) (12.8%) and Streptococcus spp (1.2%). Gram-negative rods constituted 55.1% of the total isolates with Pseudomonas aeruginosa being 8.5%, Escherichia coli 5.1%, Citrobacter freundii and Salmonella spp 2.5% each. Antibiotic sensitivity test revealed all isolates to be multi-resistant to traditional antimicrobials, which is of epidemiologcal importance in treating cases of chronic osteomyelitis in this environment. The study suggests institution of aggressive therapeutic interventions to avert possible sequalae.
Introduction: The production of polygalacturonase during the deterioration of tomato fruits by Rhizopus arrhizus Fisher. was investigated. The enzyme was partially purified by a combination of ammonium sulphate precipitation, gel filtration and ion-exchange chromatography. Optimum activity of the polygalacturonase was at 35 °C , pH 4.5 and the substrate concentration at half maximum velocity (km values ) for the hydrolysis of pectin by the polygalacturonase fractions (Da, Db and Ea ) were 3.8, 2.8 and 2.9 mg/ml. The enzyme was stimulated by Na+, K+, Ca²+ and Mg²+ but inhibited by EDTA, DNP and HgCI2. The enzyme was highly susceptible to heat, losing all its activity within thirty minutes of heating at 70 °C.
Introduction: Asymptomatic bacteriuria presents a considerable risk to the mother and may lead to onset of acute pyelonephritis in about 5% of pregnant women and also increase the risk of fetal mortality. Apart from one previous study, no other study has been carried out in this environment hence our study. The objectives are to determine the prevalence of asymptomatic bacteriuria amongst pregnant women in the three trimesters of pregnancy, to isolate and characterize the bacteria agents involved in this condition and recommend methods of reducing incidence and possible attendant sequalae. A descriptive study with purposive sampling carried out at the Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife Southwestern Nigeria between May 2000 and April 2001 examined two hundred and one consecutive pregnant women attending the antenatal clinic. This included women in the three trimesters of pregnancy. Those with urinary tract infections were excluded. Each subject was given a sterile universal bottle and requested to collect midstream urine. Each sample was plated onto Cystein-Lactose-Electrolyte-Deficient (CLED) medium and chocolate agar (CA). The major bacterial colonies were isolated and characterized employing standard bacteriologic methods. The prevalence rate was 26%. Staphylococcus aureus was predominant (43.8%), of which 68.8% were beta-lactamase producers. Forty six point six percent of total isolates were Gram-negative rods; Klebsiella pneumoniae (6.8%), Escherichia coli (4.5%), Citrobacter freundii (4.5%) and others. The study recorded a relatively high prevalence of asymptomatic bacteriuria. While the bacterial isolates were multi-resistant to drugs traditionally employed to treat uropathogens, they were relatively sensitive to nitrofuratoin in vitro. Because of the high prevalence of asymptomatic bacteriuria, we recommend routine screening for this condition in all antenatal clinics in this environment to reduce the incidence and probable attendant sequalae.
Introduction: Within ten days of incubation, freshly ripe tomato fruits (Ibadan local variety) obtained from a local market in Ile-Ife, Osun State, Nigeria had completely deteriorated and proteins which possessed cellulolytic activity were released. The enzyme was partially purified by a combination of ammonium sulphate precipitation, molecular exclusion chromatography and ion-exchange chromatography. The enzyme was stimulated to varying degrees by Ca++, Mg++, Na+ and K+ but was inhibited by ethylene diamine tetraacetic acid, 2, 4-dinitrophenol and mercuric chloride.
Introduction: The production of polygalacturonase during the deterioration of tomato (Lycopersicon esculentum Mill.) by Rhizopus arrhizus Fisher was investigated. The enzyme was partially purified by a combination of ammonium sulphate precipitation, gel filtration and ion-exchange chromatography. Two peaks of absorption, with molecular weight estimates of approximately 166 000 Daltons and 60 260 Daltons were obtained.
Introduction: Tomato (Lycopersicon esculentum Mill) fruits obtained from the local market in Sango Ota, Ogun State,
Nigeria were inoculated with Aspergillus niger from cultures grown in the laboratory and incubated
under appropriate conditions of temperature and moisture to initiate infection for seven days. Extensive
lesions and subsequent collapse of the tomato fruits inoculated with A. niger occurred within a week of
incubation. The uninoculated fruits retained the bright red color and remained firm throughout the
seven days. The pH and the probable implication of the results obtained from this research work can be
very useful in utilizing tomato fruits in tomato processing companies in Nigeria.
Introduction: Within eight days of incubation at room temperature (27oC), tomato (Lycopersicon esculentum Mill.) fruits infected with Penicillium funiculosum Thom. had deteriorated. Extracts from the infected fruits exhibited cellulase activity. Uninfected fruits lacked cellulase activity. The enzyme was partially purified by a combination of gel filtration and ion-exchange chromatography. On separation by molecular exclusion chromatography, two peaks of absorption with molecular weight estimates of 223,800 Daltons and 89,100 Daltons were obtained. Only the components of the peak with the lighter weight exhibited cellulase activity. The enzyme showed optimum activity at pH 4.5 and 40oC. Na+ ions and Ca++ ions stimulated enzyme activity while EDTA and Hg++ ions were inhibitory. The apparent km for the hydrolysis of carboxymethylcellulose was approximately 0.53 mgml-1. The occurrence of cellulase in tomato fruits infected with P. funiculosumThom. and its absence in uninfected fruits suggests a role of this enzyme in pathogenicity of the fungus. Cellulolytic components of the fruits are degraded, the fruits are deteriorated and lost to this post harvest pathogen. Knowledge of the conditions of growth of this fungus and properties of this enzyme will assist the farmer in optimizing production of these fruits and engaging the best conditions for preservation.
Introduction: Studies were carried out to determine the prevalence of malaria parasite infection among infants and children (0-12yrs) in Ota, Southwestern Nigeria between April and December 2008. The two hospitals used were Ota General Hospital and Covenant University Health Centre, Canaanland, Ota. Thick and thin films were made and stained using standard parasitological procedures. Structured Questionnaires were distributed to ascertain the age, sex, drugs or insecticides used and state of health of the subjects before recruiting them into the study. Overall, 215 (80.5%) of the 267 children investigated were found to have malaria infection. Age group (0-5 years) had the highest frequency rate of 84.7% with mean parasite density of 900 and the difference between the age groups was statistically significant (p<0.05). Children of illiterates from suburb villages had the highest mean parasite density of 850 with 78.1% prevalence rate. 20% of the children were given local herbs and 22% used orthodox medicine as prophylaxis. Only 18% used insecticide treated mosquito nets while 24% of the parents spray insecticides to prevent mosquito bites. There is therefore need for more awareness on effective use of drugs and Insecticide Treated bed nets in malaria hyperendemic regions.
Introduction: Studies were carried out on four different Species of wild mushrooms: Lentinus subnudus, Chlorophyllum molybditis, Marasmus species and Pleurotus tuberregium. The fungal species were analyzed for their nutritional compositions, biological and Structural characteristics. The fungal species were rich in proteins (amino acids) and carbohydrates. The fibres contained in the different species were also good sources of roughages. Moreover, their low acidity confirms their edibility. This study strongly recommends the commercialization of mushroom production as a means of additional source of protein requirements and income to the people in the developing economy of Nigeria.
Introduction: Tomato fruits infected by Aspergillus flavus Linn produced proteins with cellulolytic activity. The enzyme was partially purified by Ammonium Sulphate Precipitation, Gel filtration and ion-exchange chromatography. Three peaks of absorption A, B and C were obtained. Peak B had Cellulase activity with molecular weight of approximately 30,200 Daltons while Peaks A and C lacked Cellulase activity. Elution of components of Peak B on CM Sephadex C-25 produced four peaks of absorption designated Ba, Bb, Bc and Bd. Only components of Peaks Bb and Bc possessed Cellulase activity. Purification folds of approximately 80 and 81 were obtained for components of Peaks Bb and Bc respectively for Cellulase of A. flavus. The apparent Km values for the hydrolysis of carboxymethylcellulose by A.flavus Cellulase fractions, Bb and Bc were approximately 16.7 and 15.4mg/ml respectively. The partially purified enzyme preparations obtained from A.flavus during the deterioration of tomato fruits caused tissue maceration and cellular death. This result can be very useful in splitting and solubilization of pectic substances and pathogenicity.
Introduction: Women form the largest percentage of sellers and buyers in markets all over the world. There are lots of benefits to be derived from guava (Psidium guajava Linn.) fruits but a large percentage of guava fruits produced annually are lost to pre harvest deterioration caused by microorganisms. Four fungal pathogens, Aspergillus niger, Rhizopus sp., Fusarium sp., Penicillium sp. and yeast cells were found to be associated with pre-harvest deterioration of Guava (P. guajava Linn.) in Ota, Ogun State, Southwestern Nigeria. A. niger, Penicillium sp. and yeast cells were the most prevalent while Penicillium sp. was the most pathogenic, inducing a rot of 61 mm in diameter within seven days of incubation. The ash and moisture contents of the uninfected fruits were higher than that of the infected ones. The results of this present investigation could be utilized in juice making industries in Nigeria as well as for the local women who deal directly with the selling and buying of these fruits in our markets.
Introduction: Staphylococcus aureus was isolated from an individual with acne. The isolate was Gram positive, spherical and in clusters, golden yellow on mannitol salt agar and non spore forming. Biochemical tests showed that it was unable to hydrolyze gelatin but able to ferment glucose, galactose and mannitol. It produced catalase and coagulase enzymes. It was able to utilize citrate as sole carbon source but was indole negative. It was Methyl Red positive and Voges-Proskauer negative. It was sensitive to gentamicin, tetracycline, amoxicillin, augmentin, chloramphenicol and sulphamethoxazole but resistant to ampicillin, erythromycin, cloxacillin, cotrimoxazole, streptomycin and penicillin.
Introduction: Microorganisms, especially bacteria are the major causes of spoilage in fresh fish. In the coastal areas of developing tropical countries where ambient temperatures are usually high and access to modern preservation and processing technologies is low, fish is often left under ambient conditions for long periods after capture, resulting in quality deterioration and spoilage with attendant increases in post harvest losses. This study was carried out to identify, characterize and estimate the number of colony forming units (CFU) of microorganisms associated with freshly slaughtered African catfish, Clarias gariepinus held at ambient temperatures. Microorganisms were isolated from the flesh, gills, guts, mouth and skin of fish samples at successive 6-hour intervals post-slaughter for 42 hours when the fish were adjudged spoilt by a 5-member trained assessment panel. Determination of viable bacterial count was carried out by introducing aliquots of three dilutions of samples into nutrient agar plates, incubating at 37oC for 24hrs and counting the number of CFU. Microorganisms were thereafter identified using colonial and morphological characteristics and biochemical tests. Organoleptic assessment of fish samples were carried out by a 5-man trained panel. Results showed that a total of eleven microorganisms of pathogenic and/or spoilage importance were isolated at various intervals from fish samples, including Acinetobacter spp, Bacillus subtilis, B. megaterium, Citrobacter freundii, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, K. pneumoniae, Proteus mirabilis, Pseudomonas lundensis and Staphylococcus aureus. Generally the number of CFU from various parts of fish increased significantly (P < 0.05) as time interval increased.
Introduction: A research work was carried out on diseased carrots obtained from the main Sango Ota market to isolate microorganisms associated with post harvest deterioration of carrots. Small portions (2 x 5mm) of the diseased parts of carrots were aseptically inoculated on Nutrient agar and Saboraud agar incubated at 37OC and 26OC respectively. The fungal species isolated were Aspergillus niger, Penicillium notatum, Mucor spp. and Fusarium spp. and they were identified using morphology and microscopy. The bacterial species isolated were Bacillus spp., Leuconostoc spp., Xanthomonas spp and Klebsiella spp and they were identified using microscopy, morphology and various Biochemical tests. Extracellular enzyme production was carried out on the isolates to test for their ability to elaborate Amylase and Protease. All the isolates except Aspergillus niger produced Amylase. Leuconostoc spp., Xanthomonas spp., Klebsiella spp. and Aspergillus niger elaborated Protease. The results of this present investigation with further studies on carrots can be utilized in carrot juice production which is not commonly available in Nigeria.
Introduction: Pectinase is used commercially in the clarification and extraction of fruit juice from different fruits. Green apples and Red apples obtained from the fruits section of a supermarket, Idiroko road, Ota were surface sterilized and inoculated with Aspergillus niger. The stock culture was subcultured on Sabouraud Dextrose agar plates and 72-hr-old culture of Aspergillus niger served as the inoculum. The fruits were incubated for twenty-five days at room temperature (25 °C). Control fruits were similarly treated except that sterile inoculum was used for the inoculation. Extracts from the inoculated fruits exhibited appreciable polygalacturonase activity while those from the uninoculated fruits possessed only traces of the enzyme activity. The polygalacturonase obtained after enzyme extraction was applied to freshly ripe apple fruits under controlled experimental conditions to investigate the role of polygalacturonase in the production of apple juice. The juice in the cylinder to which polygalacturonase was added was visually clearer and more than that with distilled water. The optimum temperature of incubation for the clarification of apple fruits with polygalacturonase obtained from apple fruits deteriorated by Aspergillus niger was 25 °C.
Introduction: Escherichia coli were isolated from water from two boreholes in Ile Ife, Osun state, Nigeria. This was an indication of faecal contamination. These strains of Escherichia coli were Gram negative short rods, Catalase positive, Methyl red positive, Voges Proskaeur negative. The strains could ferment glucose galactose, sucrose, lactose, mannitol and maltose with the production of acid and gas but could not hydrolyze starch. A particular strain was resistant to sulfamethoxazole, ampicillin, cotrimoxazole, cephaloridine, streptomycin, carbenicillin, sulfafurazole and tetracycline but sensitive to gentamicin, colistin, nalidixic acid, nitrofurantoin and colistin sulphate
Introduction: Studies were carried out to determine the antiplasmodial activity of crude n-hexane and ethanolic seed extracts of Moringa oleifera using cold extraction method. Twenty-four albino mice (Mus musculus) induced intraperitoneally with chloroquine sensitive Plasmodium berghei strain were divided into 4 groups and treated at three concentrations viz: 50, 100 and 200 ml/kg. Positive control was set up with chloroquine diphosphate while negative control was set up with olive oil. The mice models were treated for 72 h. For the ethanolic extract, a parasite inhibition rate of 61% was observed at concentration 50 ml/kg, 65% at concentration 100 ml/kg and 100% at concentration 200 ml/kg in day 3 after treatment. In n-hexane extract of the seeds of M. oleifera, plasmodial inhibition rate of 61% was observed at concentration 50 ml/kg, 70% at concentration 100 ml/kg and 97% at concentration 200 ml/kg after treatment for 72 h. A 100% inhibition rate was observed for mice treated with 25 mg/kg of standard chloroquine diphosphate after day 3 of treatment while parasitaemia increased from 48 on day 0 to 86 after day 3 for mice treated with olive oil. Overall, crude ethanolic extract of M. oleifera seed showed higher parasite inhibition activity than the crude n-hexane extract
Introduction: Background: Plasmodium falciparum the main causative agent of malaria is an important public health vector. With the use of PCR, its genetic diversity has been extensively studied with dearth information from Nigeria.
Methods: In this study, 100 P. falciparum strains merozoite surface protein 1( msp-1), merozoite surface protein 2 (msp-2) and Glutamate rich protein (Glurp) from Ogun State General Hospitals were characterized. The genetic diversity of P. falciparum isolates was analyzed by restriction fragment length polymorphism following gel electrophoresis of DNA products from nested polymerase chain reactions (PCR) of their respective allelic families KI, MAD 20, RO33 (MSP-1);FC27, 3D7 (MSP-2) and Glutamate rich protein respectively.
Results: Majority of the patients showed monoclonal infections while multiplicity of the infection for msp-1 and msp-2 were 1.1 and 1.2 respectively. The estimated number of genotypes was 8 msp-1 (4 KI; 3 MAD; 1 RO33) and 6 msp-2 (3 FC27; 3 3D7). 80% of the isolates coded for Glurp with allelic size ranged between 700 and 900 bp.
Conclusion: The allelic distributions however were similar to those previously reported in other endemic malaria countries. Future studies will be designed to include other malaria endemic regions of Nigeria such as the oil exploration regions.
Introduction: The resistance of human malaria parasites to antimalarial compounds has become of considerable concern, particularly in view of the shortage of novel classes of antimalarial drugs. One way to prevent resistance is by using new compounds that are not based on existing synthetic antimicrobial agents. Sensitivity of one hundred (100) P. falciparum isolates to chloroquine, quinine, amodiaquine, mefloquine, sulphadoxine/pyrimethamine, artemisinin, Momordica charantia (Ejirin,) Diospyros monbuttensis (Eegun eja) and Morinda lucida (Oruwo) was determined using the in-vitro microtest (Mark III) technique to determine the IC50 of the drugs. All the isolates tested were sensitive to Quinine, Mefloquine and Artesunate. Only 51% of the isolates were resistant to chloroquine, 13% to amodiaquine and 5% to sulphadoxine pyrimethamine respectively. Highest resistance to chloroquine (68.9%) was recorded among isolates from Yewa zone while highest resistance to amodiaquine (30%) was observed in Ijebu zone. Highest resistance to sulphadoxine and pyrimethamine was recorded in Yewa and Egba zones respectively. A significant positive correlation was observed between the responses to artemisinin and mefloquine (P=0.001), artemisinin and quinine (P=0.05), Quinine and mefloquine (P= 0.01). A significant negative correlation was observed between the responses to chloroquine and mefloquine (P=0.05). Highest antiplasmodial activity was obtained with the ethanolic extract of Diospyros monbuttensis (IC50 = 32 µg/ml) while the lowest was obtained from Morinda lucida (IC50 =250 µg/ml). Natural products isolated from plants used in traditional medicine, which have potent antiplasmodial action in vitro, represents potential sources of new antimalarial drugs.
Introduction: The widespread of drug resistant Plasmodium falciparum has led to a rise in malaria-associated mortality most especially in sub-Saharan Africa. Falciparum malaria was confirmed by microscopic examination of Giemsa-stained blood samples of patients who presented with fever in selected State Hospitals in Ogun State, Southwestern Nigeria. Molecular methods were employed to detect the markers of resistance of P. falciparum to Chloroquine, sulphadoxine/pyrimethamine,and artesunate in Ogun State, Southwestern Nigeria. DNA was extracted from patient blood using the QiaAmp DNA Blood Minikit extraction method. Nested Polymerase Chain Reaction followed by Restriction Fragment Length Polymorphisms (PCR/RFLP) were used for the detection of P. falciparum chloroquine resistance transporter (Pfcrt), P. falciparum multidrug resistance 1 (pfmdr1), P. falciparum dihydrofolate reductase (Pfdhfr), P. falciparum dihydropteroate synthase (Pfdhps) and P. falciparum sarco/endoplasmic reticulum calcium-dependent ATPase (SERCA) PfATPase6 genes. Pfcrt (K76T ) Pfmdr1 (mdr 1 ) Pfdhfr (S108N), and Pfdhps (K540E) resistant genes were detected among the isolates while resistant SERCAPfATPase6 gene which codes for artemisinin resistance was not detected in the population.
Introduction: Lycopene is the carotenoid which gives tomatoes and other red fruits their characteristic colour. It is one of the most powerful antioxidants and singlet oxygen quenching agents. It has been found to be of great medical importance with various anticancer effects and its ability to ameliorate several other medical conditions. Freshly ripe tomato fruits of the Roma vf variety and the Ibadan local variety were allowed to deteriorate after infection with a 96-hr-old culture of Aspergillus niger. Extraction of cell wall degrading enzymes produced during the deterioration process was carried out ten days after inoculation of the tomato fruits. The crude enzymes were precipitated using ammonium sulphate precipitation technique and employed in the extraction of lycopene from tomato peels. The yield of lycopene was 45.25mg/kg and 45.86mg/kg for enzymes extracted from the Roma vf and the Ibadan local varieties of tomato fruits respectively. This study established an improvement in lycopene extraction with crude preparation of cell wall degrading enzymes and compared the yield from the two enzymes obtained from the two most commonly available varieties of tomato fruits in Nigerian markets.
Introduction: The ability of microorganisms to cause grape (Vitis vinifera) fruit deterioration by production of pectinolytic and proteolytic enzymes to degrade the plant cell was carried out in the Microbiology laboratory of the Department of Biological Sciences, Covenant University, Ota, Ogun State, Nigeria. A bunch of grape fruit was purchased from a local market in Ikeja, Lagos, South West, Nigeria. These samples were allowed to rot for five days in a clear packaging bag. The grape samples were disinfected and cultured on nutrient agar and potato dextrose agar for bacterial and fungal isolates respectively. The morphological and microscopic characteristics of the isolates in combination with a series of biochemical tests were used to identify them. The isolates were tested for their ability to produce pectinolytic and proteolytic enzymes. Aspergillus sp, Mucor sp, Rhizopus sp., Micrococcus sp., and Bacillus sp. were the organisms isolated from this study. The results of this investigation revealed appreciable pectinolytic, and proteolytic enzymes by Aspergillus niger and Bacillus sp. These organisms can be utilized as good sources of industrial enzymes.
Keywords: Grape (Vitis vinifera) fruits; Pectinase, Protease, Fungal isolates and Bacterial isolate.
Introduction: Lycopene is the carotenoid which gives tomatoes and other red fruits their characteristic colour. It is one of the most powerful antioxidants and singlet oxygen-quenching agents. Lycopene has been found to be of great medical importance, having various anticancer effects and it is able to ameliorate several other medical conditions. Lycopene had also been found to be very useful in the food industry where it is used as food additives, colourant and functional food. Lycopene, has been the focus of considerable attention for its potential health benefits (Shi et al. 2002; Rao and Rao, 2004). Results from epidemiological and experimental studies support the view that lycopene may provide protection against cardiovascular disease and certain types of cancer (Giovannucci, 2005; Omoni and Aluko, 2005). Lavecchia and Zuorro (2011) reported the growing demand for natural lycopene and therefore considerable interest has been directed to the possibility of obtaining lycopene from tomato processing waste. This growing demand for natural lycopene has led us to device an alternative means for the extraction of lycopene using enzymes.
Introduction: A total of forty samples of hand swabs obtained from female and male students' palms at Covenant University, Ota were studied and examined for the presence of S. aureus. The samples were inoculated on Mannitol Salt agar (MSA) and incubated at 37oC for 24h and 48h. Colonies which appeared yellow on MSA were subjected for further tests. Macroscopic examination indicated that the organism was Gram positive after the Grams staining technique and that they appeared in clusters and spherical (coccoid) in shape under the microscope. The isolates were characterized using several biochemical tests. The organism fermented Glucose, Lactose, and Sucrose with acid production without gas and Starch with gas production only. The isolates were susceptible to Ciprofloxacin, Gentamycin, Pefloxacin and Amoxycillin but resistant to Erythromycin, Ceftriazone and Cotrimoxazole antibiotics. The effect of hand treatments on the microbial flora of the palms were studied and washing of hands thoroughly with soap, water and using an alcohol based hand sanitizer can prevent the spread of staphylococcus skin infections.
Introduction: Quality drinking water is of basic importance to human physiology and man
’
s
continued existence depends much on its availability. Water samples from different outlets and
homes in Ado Odo - Ota Local Government, Ogun state, Nigeria were analyzed for their
microbiological and physiochemical properties. Total viable count was assessed by the pour plate
technique, while physiochemical evaluations was carried out using Standard Chemical Methods
such as pH analysis, physical appearances, Total Dissolved Solid (TDS), as well as tests for
chloride, sulphate, calcium, zinc and oxidizable substances. All the water samples were found to
harbor coliforms in numbers greater than the required World Health Organization (WHO) and the
Food and Agricultural Organization (FAO) standards for water. The total viable counts for all the
water samples were generally high, exceeding the limit of 1.0 × 102
cfu/ml for water, while all the
samples tested passed the physicochemical tests except the test for chloride.
Introduction: In this investigation, a defined medium was inoculated with Candida albicans and Fusarium sp. Incubation was at 28oC. The composition of the medium was potassium dihydrogen sulphate, magnesium sulphate, calcium sulphate, hydrated iron sulphate, manganese sulphate, copper sulphate, zinc sulphate, thiamine, biotin, sodium nitrate (nitrogen source) and galactose (carbon source). Proteins which exhibited
Introduction: Studies were carried out on deteriorated apples obtained from the Just Rite supermarket, Ota, Ogun State, Nigeria, to isolate microorganisms associated with post-harvest deterioration of apple (Malus domestica) fruits. The bacterial species were identified using microscopy, morphology and various biochemical tests while macroscopy and morphology was used to identify the fungi isolated. The ability of the isolate to elaborate extracellular amylase and protease were tested for. Results revealed Aspergillus niger and Aspergillus flavus as the fungal species while the bacterial species isolated were Bacillus spp and Micrococcus spp. All the isolates except Aspergillus niger produced amylase in substantial amount. Micrococcus spp, Aspergillus niger and Aspergillus flavus produced protease. The results of this investigation if combined with further studies can be used in identifying organisms which could be used as a biological method in the control of apple pathogens.
Introduction: The resistance of human malaria parasites to anti-malarial compounds has become considerable concern, particularly in view of the shortage of novel classes of anti-malarial drugs. One way to prevent resistance is by using new compounds that are not based on existing synthetic antimicrobial agents.
Introduction: The effects of exposing juveniles of African catfish (Clarias gariepinus) to two commonly used herbicides were studied over 8 weeks. Some fish biochemical parameters were evaluated over the period of the experiment. Fractionated concentrations of glyphosate (0.0265, 0.053 and 0.106 mg L-l) and paraquat (0.0035, 0.007 and 0.014 mg L-l) were administered to fish juveniles for eight weeks. These concentrations represent fractions of the 96 h LC50 which was determined in an earlier study. Antioxidant enzymes were analysed in the liver of the fish every fortnight. Comparing with the control, significant increases (p<0.05) in enzyme activities of superoxide dismutase (SOD), catalase (CAT), lipid peroxidation (LPO) and in glutathione peroxidase (GPx) were observed. These parameters were however not all concentration and time dependent. The result revealed that the two herbicides caused changes in fish antioxidant enzymes, as such could be useful in forestalling the ecotoxic effects of similar chemicals in the environmental xenobiotics
Introduction: There are different varieties of Apple fruits which have resulted from natural cross-pollination involving different species. Apples are often eaten in a raw fresh form, sometimes baked or stewed for other uses. They have some beneficial purposes such as helping in preventing the growth of prostate cancer, improving bowel function and regulating blood sugar. The activity of enzymes is usually affected by factors such as temperature, pH, substrate concentration, and enzyme concentration. The effect of enzyme concentration on pectinase obtained from the deterioration of three different varieties of apple fruits by Aspergillus niger was therefore investigated. A 72-hours-old culture of Aspergillus niger subcultured onto fresh Potato Dextrose Agar (PDA) plates was inoculated into three different varieties of fresh Apple fruits obtained from a Supermarket along Idiroko road, Ota, Ogun State, Nigeria. The fruits were surface sterilized, inoculated with the fungi and o incubated at room temperature of 27 C. They were monitored for complete deterioration over twelve days. Pectinase obtained from the deteriorated fruits was used in clarifying apple juice from the different varieties of apple fruits with different volume of enzyme. Equivalent volume of water was also treated in like manner. The same experiment was carried out for commercial pectinase in comparison with the laboratory-produced – pectinase was also more effective than the commercially produced enzyme. The result of this investigation will be very useful in the production of commercial pectinase obtained from fungal deterioration.
Introduction: This study was carried out to determine the growth and production of amylase by Aspergillus
chevalieri in a defined medium. A. chevalieri was grown in a synthetic medium containing starch as the sole carbon source. Culture filtrate exhibited amylase activity. Optimum enzyme activity was observed on the tenth day of incubation. The presence of NaCl and MgCl2 stimulated amylase activity while EDTA and HgCl2 in the reaction mixture caused a reduction in the activity of the enzyme. The activity of the enzyme was optimum at 35oC and pH 6.5. The amylase of Aspergillus chevalieri was heat labile, losing its activity completely after twenty minutes of heating at 70 oC. The amylase produced by this fungus is of significance in the brewing industry and pharmaceuticals. The observed properties would aid in preserving the enzyme and knowing optimum conditions for activity to assist in maximizing industrial output.
Introduction: Aspergillus niger is a saprophytic fungus existing ubiquitously in the soil and on decaying vegetation. Various researchers have reported Aspergillus niger as frequently responsible for postharvest decay of fresh fruits such as apples, pears, grapes, melons, onions and some vegetables. The fungus has been implicated in the deterioration of apple fruits with the production of Pectinolytic enzymes during the breakdown of the plant cell wall by microbial attack. The three varieties of apple (Malus domestica) fruits used for this work are commonly referred to as Red, Green and Yellow varieties from their physical appearance. The fruits were obtained from a grocery store along Idiroko road, Ota, Ogun State in Nigeria. The fruits were disinfected and inoculated with a 72-h-old culture of A. niger. Control fruits were inoculated with sterile inoculum. The fruits were incubated at room temperature of 27oC for twelve days. Extracts from the inoculated fruits exhibited appreciable polygalacturonase activity while those from the uninoculated fruits possessed only traces of the enzyme activity. The enzyme obtained from the deteriorated fruits and commercially produced pectinase were applied for the clarification of freshly ripe apple fruits under controlled experimental conditions at different temperatures (20oC, 25oC, 30oC, 35oC, 40oC and 45oC) to investigate the role of pectinase in the clarification of apple juice. The temperature of incubation had different effects on the three varieties of apple fruits studied. The volume of juice was more in the cylinders with the enzyme clarification at all temperatures than that with water. The optimum temperature was at 25oC for the three varieties green and red apples. The commercial pectinase produced more juice than the crude pectinase.
Introduction: The thermal and antimicrobial properties of air drying polyesteramide-urethanes (hybrid) synthesized from Thevetia peruviana (a tropical and underutilized ornamental shrub) seed oil (TPSO) were evaluated. Physico-chemical characterizations (such as hydroxyl value, iodine value, saponification value, refractive index, inherent viscosity) of the resins were carried out using standard procedures. The polyesteramide was synthesized by reacting N, N'- bis(2- hydroxyethyl) Thevetia peruviana (I-IETA) [a product of aminolysis of TPSO] with Isophoronediisocyanate (IPDI). FTIR, 1H-NMR and 13C-NMR spectroscopic methods were used in structural .elucidation of the air dried hybrid urethanes. Antimicrobial activities as well as thermal stability (using TGA and DSC) of the coating films were evaluated. The SEM micrograph of the hybrid film and corrosion inhibitive test was also exa.rilined.
Introduction: This paper describes the antimicrobial and corrosion inhibitive properties of synthesized polyesteramide resin from Moringa oleifera seed oil (MOSO). N,N'-bis (2-hydroxyethyl) Moringa oleifera oil fatty amide (HEMA) was synthesized via aminolysis from MOSO. The fatty amide obtained from aminolysis (HEMA) undergoes polycondensation reaction with adipic acid to form polyesteramide (MOPEA). The synthesized polyesteramide resin was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), Carbon 13 nuclear magnetic resonance (13C NMR) spectroscopic analyses and thermogravimetric analysis (TGA). Selected physico-chemical parameters of MOSO, HEMA and MOPEA were examined. Coating performance, thermal stability and antimicrobial properties of the cured resin (MOPEA) were evaluated.
Introduction: Chitinases are hydrolytic enzymes that break down the glycosidic bonds in chitin. The role of Chitinases in the
treatment and prevention of various diseases have been reported. They have been implicated in the human health care for the
treatment of fungal infections, in Asthma and in the control of mosquito which causes the deadly malaria disease accounting
for about 70% of infant mortality in Africa. Chitinase was obtained from chitinolytic bacteria inhabiting the skin and gut of
the African Catfish (Clarias gariepinus). Bacterial population Isolated from catfish was screened on colloidal-chitin agar
medium. The ability to produce Chitinase was determined by zones of hydrolysis produced after 96h of incubation at 37oC.
Isolation of chitinase was carried out with colloidal chitin as substrate in sodium phosphate buffer. Optimum conditions were
therefore ascertained at a temperature of 500C and a substrate concentration of 0.15g for chitinase produced by bacteria spp
(isolate code 17 and 36) while pH 5.5 was obtained for isolate code 36 and pH 6.0 for isolate code 17. The Michaelis –
Mentens constant (Km) which is also known as the dissociation constant is the substrate concentration at half maximum
velocity. Calculated from the Lineweaver-Burk plot, the apparent Km values for the hydrolysis of chitin by chitinolytic
bacterial isolate code 36 and isolate code 17 were approximately 0.09mg/ml and 0.007mg/ml respectively. Isolation of DNA
and PCR amplification carried out identified the bacteria as a member of the genus Bacillus. This study established that
species of Bacillus inhabiting the gut and skin of the African catfish can be used for Chitinase production in appreciable
quantity.
Introduction: Aspergillus niger is a soil saprobe and produces a wide array of hydrolytic and oxidative enzymes and cell wall degrading enzymes. An investigation on the various properties of partially purified polygalacturonase and cellulase enzymes extracted from tomato fruits deteriorated by Aspergillus niger was carried out in this study. The results obtained shows that temperature, pH and substrate concentration have a profound effect on enzyme activity. The molecular weights of the enzymes extracted also suggest that it may be species dependent
Introduction: There is a need for locally produced xylanase because of its vast importance and high cost of importation. Xylanase is used for many industrial processes such as for baking, bleaching paper pulp, bioethanol production and juice clarification. This study was therefore carried out to examine the potentials of tomato pomace as part of the growth medium for xylanase production. The objectives are to identify the specific activities of xylanase from the basal salt medium and the tomato pomace medium and to determine the Partial Purification of xylanase obtained from tomato pomace medium inoculated with A.niger This study isolated xylanase from A. niger on tomato pomace medium. The xylanase was partially purified and characterized. A. niger was obtained from deteriorated banana (Musa acuminata) fruit. A 72-h-old culture of A. niger was employed as the inoculum. It was inoculated onto Tomato pomace medium and a basal salt. Xylanase production was carried out after four days at room temperature (27 oC). Xylanase activity was determined by measuring the released reducing sugar (xylose). The specific activities of xylanase from the basal salt medium and the tomato pomace medium were 3.6 U/mg and 2.0 U/mg respectively. Partial purification of xylanase was by Ammonium sulphate precipitation. Optimum substrate concentration of 0.5mg/ml and a purification fold of 4.3 were obtained. The Michael is Menten constant (Km) from the Line-weaver burk plot was approximately 0.50mg/ml. This study established appreciable activity of xylanase from the A. niger used. It is therefore a potential organism for the utilization of tomato waste for xylanase production.
Introduction: Despite progress in the development of antibacterial agents, there are still special needs to find new antibacterial agents due to the development of multidrug resistance by bacteria and fungi.This study was conducted to investigate and compare the in vitro antibacterial and antifungal activities of the methanolic and ethanolic extracts of the leaves of Chrysophyllumalbidum and Diospyrosmonbuttensis.Methanolic and ethanolic extracts of D. monbuttensis and C. albidum leaves were prepared using cold extraction method. Antimicrobial sensitivity testing was carried out using agar-well diffusion method against the following test organisms: Staphylococcus aureus, Streptococcus sp., Escherichia coli (Enteropathogenic), Klebsiellasp., Candida albicans and Aspergillusniger. Minimum inhibitory concentration of the extracts of D. monbuttensis and C. albidum leaves was determined using broth dilution method. S.aureus, Streptococcus sp., E. coli andKlebsiellasp. were sensitive to ethanolic leaf extract of C. albidum at 25, 50 and 100mg/ml respectively. Streptococcus sp.,E. coli (Enteropathogenic), Klebsiellasp. AndC. albicanswere sensitive to C. albidum at 25and 50mg/ml. A. niger showed resistance to both extracts at the different concentrations used. The MIC of the methanol and ethanol leaf extracts of D. monbuttensis and C. albidum against the test microorganisms ranged between 3.125 and 100mg/ml. This is indicative that D. monbuttensis and C. albidum leaf extracts can be used in the treatment of infections
Introduction: The soursop fruit and the entire soursop plant is associated with a lot of health benefits which includes the killing of cancer cells in cancer patients. The treatment of cancer with soursop has been reported to be accompanied with the risk of Parkinson’s disease while soursop juice is considered safe for consumption. The fruit had been associated with preharvest and postharvest deterioration caused by microorganisms and this reduces the total production of soursop fruit. The deterioration process is being accompanied with the production of cell wall degrading enzymes which has the advantage of being used for industrial purposes. One of the important uses of these enzymes is in the clarification of fruit juices. This review proposes the genetic modification of the genes coding for important microbial enzymes for the clarification of soursop juice for improved yield, taste, and colour.
Introduction: Two varieties of tomato fruits commonly available in Nigerian markets are the Roma VF and Ibadan local varieties of tomato fruits. The Roma VF fruits are oval in shape. It is a common type of cultivar in the Northern region of Nigeria and it is not susceptible to cracking. The Ibadan local variety of tomato fruits is a local variety commonly found on farmers fields in South-western region of Nigeria. They are highly susceptible to cracking. The Ibadan local variety was employed for this research. There are lots of benefits derived from the consumption of tomato fruits. The fruits can be made into tomato juice clarified with pectinases. Polygalacturonase is one of the pectinases used commercially in the clarification of fruit juice from different fruits. This study examined the production of polygalacturonase during the deterioration of tomato fruits by Aspergillus niger and the role of the purified polygalacturonase in the clarification of tomato juice. Tomato fruits of the Ibadan local variety were inoculated with mycelia discs containing spores of a 96-h-old culture of Aspergillus niger served as the inoculum. The organism from the stock culture was subcultured onto potato dextrose agar plates. The extraction of polygalacturonase after 10 days of incubation at 27 degrees C was carried out by homogenizing the fruits with liquid extractant using the MSE homogenizer after the deteriorated fruits had been chilled for 30 min inside a freezer. Control fruits were similarly treated except that sterile potato dextrose agar served as the inoculum. The effect of different temperature of incubation and different volume of enzyme on the tomato juice from the tomato fruits was investigated. Extracts from the inoculated fruits exhibited appreciable polygalacturonase activity. The juice with polygalacturonase was visually clearer and more voluminous than the juice treated with water for all parameters studied. The highest volume of juice was obtained after an incubation period of 30 min for the tomato fruits. The increase in juice yield can be attributed to the hydrolysis of pectin which releases the sap inside the cells of the pulp. The occurrence of polygalacturonase in tomato tissues infected by A. niger coupled with the trace amount in the non-infected tissues suggests that the enzyme is of fungal origin. The role of the polygalacturonase in the clarification process was established. This study will be very useful for industrial tomato juice production.
Introduction: Amylases are enzymes that act on starch, converting it into sugars by their catalytic activities. They are highly rated amongst enzymes because of their numerous applications in industries. Microorganisms are the best source of amylase and they are advantageous because they can easily be exploited to produce the enzyme, ?-amylase. This research work therefore, employed a strain of Rhizopus arrhizus fisher which was capable of growth on 1% flour medium for the production of ?-amylase within ten days of incubation. ?-Amylase activity was optimum on the 8th day of inoculation and was expressed as 933 U. The crude enzyme was partially purified by a combination of ammonium sulphate precipitation and dialysis. The activity of the partially purified enzyme was optimum at 30°C and pH 6.0. The enzyme was capable of degrading starch with an optimum activity expressed at 1.2 mg mL–1 concentration. It was stimulated by NaCl and CaCl2 but inhibited by P-chloromercuric benzoate and Ethylene Diamine Tetraacetic Acid (EDTA). The enzyme was affected by heat with complete loss of activity within 10 min of heating at 70°C. Rhizopus arrhizus can therefore be suitably genetically modified and employed for the commercial production of ?-amylase.
Introduction: Salmonella and Plasmodium infections are major health challenges especially in regions where malaria is highly endemic. Studies were carried out to determine the incidence of co-infection of Salmonella spp and Plasmodium falciparum among subjects that present with fever at the Covenant University Health Centre and Ota General Hospital between September, 2011 and May, 2012. Salmonella infection was detected by comparing two diagnostic methods: serology and culture on the blood samples collected. Widal test was carried out by detecting the ‘O’ and ‘H’ antigens in the blood and the blood samples were cultured using Thioglycolate broth and Salmonella Shigella agar. Plasmodium infection was confirmed through microscopic examination of Giemsa stained thick and thin films of the same blood samples. Out of the 84 samples collected, 45.2% was positive for Salmonella and Plasmodium co-infection by Widal test with positive titre ? 1/80. Only 3.6% was confirmed for co-infection of Salmonella and Plasmodium Species when Salmonella infection was detected by culture. Among the 84 subjects 73.8% was positive for malaria alone and 67.9% for Salmonella infection alone. Laboratory confirmation of co-infection of malaria and Salmonella is essential to prevent wrong treatment and misdiagnosis.
Introduction: Rhizopus stolonifer is a fungus and one of the most common species of the genus Rhizopus. The organism has been a very important microbe used in the field of industrial microbiology. It has been used in the production of many hydrolytic and extracellular enzymes among which is the "-amylase. This enzyme has found various uses in the industry. Fruit juices are important sources of nutrients and they contain several important therapeutic properties that may reduce the risk of various diseases. An investigation on "-amylase extracted from soursop fruits deteriorated by R. stolonifer and the effect of the enzyme on soursop juice clarification was carried out in this study. The results obtained shows that the soursop juice with low concentration of extracted enzyme and less incubation time was more viscous and cloudy compared with the juice with high concentrations of amylase and higher incubation time which was clearer and less viscous. The results of this research will be very useful in soursop juice producing companies
Introduction: Biochemical Oxygen Demand (BOD) is a measure of the dissolved oxygen consumed by microorganisms during the oxidation of reduced substances in waters and wastewaters. It is often used ambiguously in relation to Carbonaceous Oxygen Demand CBOD) which is the oxygen consumed during the oxidation of carbonaceous compounds to carbon dioxide (CO2and other oxidized end product. BOD is actually the sum of CBOD and NBOD where NBOD is the Nitrogenous Oxygen Demand which is the oxygen consumed during the oxidation of nitrogenous compounds (mainly NH to nitrates with nitrites being an unstable intermediate. The major difference between CBOD and NBOD is that there are two classes of bacteria believed to be responsible for the oxidation of reduced nitrogen. The BOD value of Sewage samples collected from Covenant University oxidation pond was therefore measured and the samples examined for the presence of Escherichia coli. The sewage samples collected from four points (starting point (A), two middle points (B, C), and end point (D) were inoculated on an Eosin Methylene Blue agar plates and the presence of E. coli was confirmed by the appearance of greenish metallic sheen colonies on the agar plates and biochemical Tests. The BOD of the effluent at the different points (A, B, C, D) respectively showed a reduction in microbial load. The ultimate CBOD was also estimated based on the BOD5 value which is based upon the exponential (first-order) nature of oxygen demand. This research describes the formulations of CBOD breakdown using simplified oxidation kinetics.
Introduction: This study was carried out to determine the antiplasmodial activity of leaves of Moringa oleifera. Cold extraction method was carried out on grinded leaves to prepare the crude ethanolic and n-hexane extracts. Mice models (Mus musculus) were passaged with chloroquine resistant Plasmodium berghei, which are similar in morphology, physiology and life cycle to P. falciparum that infect humans. Stock solutions of 5 mg/mL 5% DMSO were prepared and the extracts were administered at different treatment concentrations, 50 mg/kg, 100 mg/kg and 200 mg/kg body weight over 4 days. Positive and negative control groups, Chloroquine diphosphate (25 mg/kg) and 5% DMSO, respectively were set up. Crude ethanolic and n-hexane extracts of M. oleifera showed anti-plasmodial activity at the three different concentrations used. Both crude ethanolic and n-hexane extracts of M. oleifera leaves showed a significant inhibition of parasitaemia (p < 0.05) ranging from 74.7 to 95.6% for ethanolic extract and 59.3 to 87.9% for n-hexane extract. EC50 value of crude ethanolic and n-hexane extracts were 32 mg/kg and 42 mg/kg body weight, respectively. M. oleifera showed potential for possible future use as an alternative to some conventional drugs. © 2016 Friends Science Publishers
Introduction: The biochemical and physiological changes in the highly proteinous stored fermented African locust bean parkia biglobosa seeds were studied as well as the sensory evaluation. This study was carried out to improve the shelf life of this fermented protein based condiment, known as ‘Iru’ in Yoruba land. Major functional parameters were used to compare deterioration in stored fermented seeds. Bacillus subtilis was used as a starter culture and fermentation was carried out for 72 hours. Samples were dried to various moisture content. The dried condiments were stored for various days at room temperature in an air tight plastic container. At the end of each storage period, samples were and assessed for pH, titratable acidity (TA), peroxide value (POV) and % crude protein. There was an increase in pH, peroxide value and titratable acidity towards acidity, while the % crude protein decreased with storage. Total dryness of 0 % moisture content was achieved after 12 hours of drying, which made the stored condiment to last for more than 31 days.
Introduction: The quality of African locust bean seed fermented with three (3) different types of starter cultures were investigated. Freshly prepared Bacillus Subtilis, Saccharomyces cerevisiae and the mixture of the two starter cultures were used for the fermentation Parkia biglobosa seeds for five (5) days (120 hours). The proximate composition, sensory evaluation and physiological properties of the starter culture aided and naturally fermented samples were determined. Sample fermented with Bacillus subtilis increased the protein composition from 32 % to 52 %, Saccharomyces cerevisiae to 39 %, the mixture of the 2 microorganisms to 35 % while 40 % was obtained in the naturally inoculated sample. Fat, moisture and ash contents also increased in the same trend. However there was a decrease in crude fibre composition and total % carbohydrate of the substrate during fermentation. Sensory evaluation carried out for all the samples indicated that the use of bacillus subtilis as starter culture for the production of ‘Iru’ gave more acceptable products in all the tested parameters. However, products from Saccharomyces cerevisiae and the mixture were rated least.
Introduction: More than half of the world's population are exposed to malaria. Rapid diagnosis and proper treatment are the main aim of control programs in malaria endemic areas. This study was aimed at developing a non-invasive diagnostic method for detection of Plasmodium falciparum in human malaria.
Introduction: In this present investigation, an original and detailed empirical data on the transfer of heat in a tomato postharvest storage system was presented. No-load tests were performed for a period of 96 h. The heat distribution at different locations, namely the top, middle and bottom of the system was acquired, at a time interval of 30 min for the test period. The humidity inside the system was taken into consideration. Thus, No-load tests with or without introduction of humidity were carried out and data showing the effect of a rise in humidity level, on temperature distribution were acquired. The temperatures at the external mechanical cooling components were acquired and could be used for showing the performance analysis of the storage system
Introduction: Optimization of Fermentation Conditions for the Production of Protein Composition in Parkia biglobosa Seeds using Response Surface Methodology
Introduction: This review examines the unparalleled chemical and physical properties of ZnO nanoparticles and its hybrid forms. The influence of these multifunctional materials within the polymeric matrix of organic coatings was discussed. The scanning electron microscope is seen to provide relevant information about the dispersion of the hybrid and composite coating systems. This review provides concise information about the antimicrobial and thermal stability of composites.
Introduction: Tannase (Tannin acyl hydrolase, EC 3.1.1.20) is an enzyme produced in the presence of tannic acid by various filamentous fungi. They are produced principally by fungi of the genus Aspergillus and Penicillium. The enzyme is used in the food and beverage industry as a clarifying agent for wines, beers and fruit juices. In Africa, billions of dollars are expended yearly on the importation of commercial enzymes for the food and pharmaceutical industries and this increases the cost of production and the finished goods. This study was carried out to isolate tannase producing fungal species using Bambara nuts as a substrate in a bid to finding alternatives to the importation of tannase. Fresh Bambara nuts were collected from different locations in Nigeria. They were cleaned, sorted and intermittently moistened with water to encourage fungal growth for fourteen days. The different fungi obtained after fourteen days were inoculated onto Potato Dextrose Agar plates and incubated at 25°C for five days. Subculturing of fungal isolates was carried out to obtain pure cultures of isolates. Tannilytic activity (hydrolysis of tannin) of isolates was assessed by inoculating them in media containing tannin. The plates were incubated at 25°C for 2-5 days after which the plates were observed and zones of hydrolysis measured. A total of eighteen isolates were obtained. They were all members of the Aspergillus genus. 56% (10) of the isolates were able to degrade tannin acid with mean zone of hydrolysis of 39mm ±23.7 mm (Range 10-70mm). This study established members of the Aspergillus genus isolated from Bambara nuts as viable fungi for application in the production of tannase. This study adds to existing reports on fungal production of tannase.
Introduction: The use of enzymes as biological catalysts has gained increasing importance in industries. Although enzymes can be obtained from plant and animal origin, microbial enzymes have several advantages over enzymes derived from other sources. Due to the high cost of separation of enzymes from product, the instability of enzymes and reduced enzyme activity, several strategies are now been explored to develop immobilized enzymes. Immobilized enzymes have been produced by cell immobilization techniques. Immobilized enzymes have found several industrial applications where they provide the advantages of easy separation of the enzyme from the product, reuse of the enzyme, convenient handling, high stability under extreme physical and chemical conditions, being applicable for all types of reactors with varied interior design, and provides easier process control. However, despite these advantages, enzyme immobilization techniques continue to pose some challenges. These challenges notwithstanding, the development of industrial by-products based on immobilization techniques is very promising.
Introduction: Background and Objective: Pimples (acne) are small skin lesions or inflammations of the skin. The most common factor causing acne is the hormonal changes that occur during adolescent and teenage years. Antibiotics are becoming less effective in the treatment of pimples due to increasing concerns of antibiotic resistance. This study was therefore carried out to characterize the isolates from the pimples of Covenant University Students and to determine their antibiotics sensitivity pattern. Materials and Methods: A total of 20 swab samples were obtained from male and female students with obvious signs of pimples in Covenant University, Ota, Ogun State, Nigeria. The samples obtained were cultured on Mannitol Salt Agar and incubated at 37EC. Pure isolates obtained were subjected to Gram staining and other biochemical tests for identification. The isolates were further subjected to antibiotics sensitivity tests using antibiotic dics. Results: Macroscopic examination indicated that the organisms were convex, smooth and shiny. Microscopic examination revealed that the isolates were positive after employing the Gram Staining technique and they appeared as grape-like clusters. Biochemical tests revealed that the isolates were Coagulase positive, Catalase positive, Urease positive, Citrate positive, Methyl-Red positive, Voges-Proskauer negative and negative upon starch hydrolysis. The sugar fermentation tests revealed that the isolates fermented Glucose, Maltose, Galactose, Sucrose and Lactose, respectively. The antibiotic susceptibility test showed that isolates were resistant to Cotrimazole, Cloxacillin, Erythromycin, Gentamycin, Augmentin, Streptomycin, Tetracycline and Chloramphenicol. Conclusion: The results therefore indicated that the isolates were Staphylococcus aureus and other staphylococci species. Indiscriminate use of antibiotics should be avoided to prevent the development of resistant strains of the Staphylococci genera and other pathogenic organisms.
Introduction: The present study described the use of percentage moisture left and salting as a preservative method in studying the shelf life of fermented Parkia biglobosa (African Locust bean seed) over a period of four weeks. Bacillus subtilis was used as starter culture in the fermentation of Parkia biglobosa to ‘Iru’. Fermented samples [Iru] were dried to various% moisture content and salt of various concentrations were added. Samples were stored for four weeks at room temperature in an air tight plastic container. Functional properties such as pH,% protein,% titratable acidity and peroxide value of the seeds were analyzed on weekly basis during the storage period. Protein concentration of the preserved samples varied with different drying time and% salt added. There was an increase in titratable acidity and peroxide values towards acidity during preservation.
Introduction: Amylases (EC 3.2.1.1) are cellwall degrading enzymes associated with the pathogenicity of microorganisms in the spoilage of tomato fruits. The use of amylase in many industries has made it very important to optimize production process to achieve maximum yields. Screening and partial purification of Amylase from Aspergillus niger isolated from tomato (Lycopersicon esculentum Mill.) fruits was studied. Amylase producing fungi were isolated from fresh tomatoes kept at ambient temperature (28±1?C). Isolates were characterized on the basis of their morphological and cultural techniques. Partial purification of amylase was carried out by ammonium sulphate precipitation. The enzyme activity was determined and optimum conditions were obtained. The molecular weights of the crude and partially purified Amylase were determined by SDS PAGE method. A total of five isolates were obtained using basic screening technique for amylase activity, one of the isolates (Isolate code F2) exhibited maximum amylase activity. The fungi isolate code F2 was identified as Aspergillus niger. Optimum conditions for Amylase AMY F2 were ascertained at pH 6.0; temperature 30°C; substrate concentration of 0.3mg/ml, and time of heating of less than 10min. The molecular weights f the crude and partially purified Amylase AMY F2 were found to be 55kDa and 35kDa respectively by SDS PAGE method. Microorganisms had been an encouraging means of economical production of enzymes in large scale for the food and drug industry.
Introduction: Pectinases are a group of enzymes that catalyze the breakdown of pectin. Pectinase producing Aspergillus niger was obtained from a five-day old Eba (Cassava flakes). Response surface methodology was used for optimizing the process of the pectinase produced. Four independent variables which are, temperature, pH, substrate concentration and time of Heating at 70oC were used to optimize the significant correlation between the effects of the variables on pectinase production. A second-order polynomial was fitted to data and validated by ANOVA. The results revealed maximum pectinase production at pH 6.0, 50oC Temperature, 0.02% substrate concentration and the enzyme lost all its activity within 7 min of heating at 70oC. The study revealed that optimization of pectinase through RSM could improve the enzymatic characteristics and yield of the enzyme. The models used were highly significant with a correlation coefficient (R2) of 0.901
Introduction: The World Heal Organization (WHO) has identified malaria diagnosis as being pivotal to eradicating the disease by 2030 as stipulated in the Sustainable Development Goals (SDG). The data presented here was obtained from outpatients of a hospital in the South Western Region of Nigeria from November 2016 to May 2017. The data contains malaria incidence amongst asymptomatic and symptomatic outpatients in the period under review. Malaria incidence was obtained using two diagnostic test kits, Bioline SD (HRP-2) and ACON (HRP-2/Aldolase) alongside Microscopy as gold standard. Specificity, Sensitivity and Kappa statistic of each test device is presented in the tables herewith. Data presented here could be used alongside other data sources to assess the state of malaria diagnostics.
Introduction: This paper examines the influence of poverty on housing in informal settlement. Housing ownership has become a paramount thing in Nigeria, due to high cost of rent. This has resulted in informal settlement and sustaining those buildings has become hectic as a result of poverty. This research work was carried out in order to highlight and examine the influence of poor housing on the health and behaviour of the residents in the study area. Data for the study were generated from both primary and secondary school sources, and were equally analyzed through Descriptive statistics. The sampling population was 250 respondents who are representative of the house heads. Findings from the study revealed that the area chosen for the study exhibit slum condition that has denied impact on the socio-economic lifestyles and the health of the residents, as well as the general outlook of the environment. The study then concludes that people should design and build their houses based on their income rather than hoping for a better future. The study also recommends public campaign, to educate the dwellers on the need for good building condition as well to know the danger of abusing their environment
Introduction: There have been reports of increasing development of drug resistance among human pathogens as well as undesirable side effects of certain antimicrobial agents.It is therefore necessary to search for new agents that are better, cheaper and without side effects for treating infectious diseases especially in developing countries. In this study, phytochemical composition and antimicrobial activities of aqueous and ethanolic extracts of leaves of Mangifera indica were investigated. Standard methods were employed to screen for the phytochemicals. Agar well diffusion method was used to determine the antimicrobial effects of aqueous and ethanolic extracts of M. indica leaves against seven different clinical isolates namely:Stapylococcus aureus, Micrococcus virians, M. leteus, Escherichia coli, Klebsellia pneumoniae, Pseudomonas aeruginosa and a fungus, Candida albicans. Phytochemical screening showed the presence of active pharmacological components such as tannins, saponins, cardiac glycoside, flavonoid and alkaloids. Aqueous extract demonstrated a higher activity than the ethanolic extract. S. aureus showed highest sensitivity to the aqueous extracts with MIC 31.25mg/mL. Least sensitivity was observed in K. pneumoniae and Candida albicans with MIC 125mg/mL each in the two extracts.M. indica exhibited significant antimicrobial activity comparable to gentamicin which is used as control in this study.
Introduction: The production of tomatoes has experienced a huge rise over the years as a result of its economic, nutritional and cancer reduction importance. Despite the rapid advancement of technology in the past century, storage of tomato fruits remains a major problem experienced in the postharvest chain in most developing countries. This study gives a survey of the various causes of tomatoes postharvest losses, the different methods used in storage of the fruit over time and their limitations. It was found that the conventional methods used in tomatoes storage, improved its shelf life but was accompanied by some significant losses in quantity and quality. Hence, generating a need for a postharvest storage system taking into cognizance the optimum conditions required for the fruit storage. The development of a thermally controlled postharvest storage system with the sole purpose of increasing shelf life and minimize the rate of deterioration becomes inevitable.
Introduction: Amylases are one of the most important enzymes used in the industry. They are responsible for the hydrolysis of starch and glycogen. This research aimed to investigate the effect of cations (Ca2+ and K+) and chemicals (EDTA and HgCl2) on alpha amylase activity. Alpha amylase was produced by Aspergillus niger under submerged fermentation conditions in a basal salt medium. The enzyme was partially purified with activated carbon which gave a 1.57 purification fold. The effects of ethylene diamine tetratacetic acid (EDTA), mercuric chloride (HgCl2), Calcium ion (Ca2+) and Potassium ion (K+) on the partially purified enzymes were then investigated. The enzyme was inhibited to varying degrees by EDTA and HgCl2 with inhibition of approximately 62% and 52% occurred with 8mM of EDTA and HgCl2 respectively, but stimulated by Ca2+ and Potassium ion K+. Activated carbon partially purified alpha amylase produced by A. niger with a high yield. The cations and chemicals had varying effects on the enzyme.
Introduction: Amylases are one of the most important enzymes used in the industry. They are responsible for the hydrolysis of starch and glycogen. This research aimed to investigate the effect of cations (Ca2+ and K+) and chemicals (EDTA and HgCl2) on alpha amylase activity. Alpha amylase was produced by Aspergillus niger under submerged fermentation conditions in a basal salt medium. The enzyme was partially purified with activated carbon which gave a 1.57 purification fold. The effects of ethylene diamine tetratacetic acid (EDTA), mercuric chloride (HgCl2), Calcium ion (Ca2+) and Potassium ion (K+) on the partially purified enzymes were then investigated. The enzyme was inhibited to varying degrees by EDTA and HgCl2 with inhibition of approximately 62% and 52% occurred with 8mM of EDTA and HgCl2 respectively, but stimulated by Ca2+ and Potassium ion K+. Activated carbon partially purified alpha amylase produced by A. niger with a high yield. The cations and chemicals had varying effects on the enzyme.
Introduction: Dacryodes edulis is a versatile plant in many African countries, as its various parts are employed to treat several diseases. Like most plants used in traditional medicine, the possible mechanism by which D. edulis functions is still unknown. This study was designed to investigate the components of the plant seed with a view of justifying its use as traditional medicine.
Introduction: Dacryodes edulis is a versatile plant in many African countries, as its various parts are employed to treat several diseases. Like most plants used in traditional medicine, the possible mechanism by which D. edulis functions is still unknown. This study was designed to investigate the components of the plant seed with a view of justifying its use as traditional medicine.
Introduction: The current wave of globalization has unlimitedly shaped the global world economy with substantial evidence of increased output growth. In the twenty first century as well, there have been global trending issues on the extent to which such output growth have been compactable with sustainable development goals (SDGs) in terms of inclusiveness of growth outcomes that can engender significant reduction in inequality and poverty. In fact, many development experts assert that mere increase in the output (GDP) without transforming the citizens thereof is a condition of jobless growth- a situation where the growth of GDP and government expenditures (in both per capita and real terms) is associated with growing poverty levels (see Johnson, 1955 and Bhagwatti, 1958 for initial expression of such growth typology and Ojameruaye, 2014 and World Bank, 2018 for recent views).
Introduction: This study examines the impacts of interest rate on private consumption behaviour in Nigeria between the period of
1981 and 2014 using autoregressive distributed lag (ARDL) co integrations framework. The data were sourced from the
World Bank development indicators; interest rate was augmented with other macroeconomic variables like per capita
income, money supply, and banking sector credit to the private sector as regresses in determining the behaviour of
private consumption in Nigeria. The results confirm the existence of relationship between private consumption and its
determinants, except real interest rate and the dummy for the impact of interest rate deregulation. The study therefore
recommends increase in government capital expenditures that will create an enabling environment for the private sector
to thrive so that the welfare of the citizenry could be enhanced.
Introduction: This study examines the impacts of interest rate on private consumption behaviour in Nigeria between the period of
1981 and 2014 using autoregressive distributed lag (ARDL) co integrations framework. The data were sourced from the
World Bank development indicators; interest rate was augmented with other macroeconomic variables like per capita
income, money supply, and banking sector credit to the private sector as regresses in determining the behaviour of
private consumption in Nigeria. The results confirm the existence of relationship between private consumption and its
determinants, except real interest rate and the dummy for the impact of interest rate deregulation. The study therefore
recommends increase in government capital expenditures that will create an enabling environment for the private sector
to thrive so that the welfare of the citizenry could be enhanced.
Introduction: In the world over, the role of customer care and customer services in most organizations has become so important that the level of profitability or performances of firms are tied to it. Thus the place of customer relation management is necessary to be understood. It is in view of this reality that this study examined the link between customer relationship and banks' profitability using empirical data obtained through the use of questionnaire from employees across 12 branches of Ecobank Plc in Victoria Island area of Lagos state. Both purposive and random sampling techniques were employed to select 96 respondents for the study. Descriptive statistics such as frequency distribution, mean, standard deviation and factor analysis of principal component were applied for the analyses of the data. One of the major identified problems was that since satisfactions is relative and vary from one customer to another, it is difficult to measure the level of satisfaction of customers which could lead to increase in profitability of the bank. However, the major finding of the study based on the views of the employees of the bank is that there is significant relationship between customer services through efficient relationship management and bank's profitability. Based on this insider views, the study concluded that customer relationship is inevitably seen as the crucial organizational capability to enhance competitive advantage and to increase bank's total profit. On this note, the study recommended that banks should continue to embark on efficient methods through which customer care services could be enhanced for increased productivity to be achieved. Also, it is expedient that the customer care units should educate the customers on recent developments in the banks especially ICT related CRM strategies so that the level of customer loyalty and long term profitability of the bank would be achieved.
Introduction: This study examined the impact of financial inclusion on poverty inclusion on poverty reduction among low income workers in Ibadan metropolis of Oyo State, Nigeria. The study specifically identified the integral roles of access to microfinance as a proxy for financial inclusion on poverty reduction. A structured questionnaire was administered to a randomly selected number (200) low income civil servants in the study area. Descriptive analysis was used to describe the behaviour of some demographic characteristics of the respondents while inferential statistical tool of logistic regression was applied to estimate the logistic impact of microfinance on poverty reduction among the selected respondents for the study. the results revealed that microcredit was found to have a positive, but low impact on the standard of living of low income workers in the study area. the study recommended that the government should make policies that would encourage continuity and sustainability of microfinance credit scheme among the sampled participants.
Introduction: The phenomenon of Asian Tigers’ economic growth miracle, coupled with the current pace of globalization has particularly increased the spread of trade tentacles of China into the hinterland of many developing nations of the world. Indeed, the need to secure resources to meet the development aspiration of China made her to increasingly forged formidable trade ties with almost all African countries especially Nigeria in the area of manufacturing products. While these realities have been proved to be beneficial to the trading partners, there is still a perceived disproportional quantum of bilateral trade flows of manufactures between Nigeria and China. Therefore, this study examined these concerns by characterizing some basic stylize facts on the existing intensity of trade differentials between these partners for the period of 1995 to 2012. From the trend analyses, we found evidence of increasing trade imbalance as exports of China’s manufactures to Nigeria soared, while that of Nigeria outflow to them is of low magnitude. Therefore, strengthening the export capacity of manufacturing firms in Nigeria, as well as promoting a broad based diversification of Nigerian economy is crucial for more beneficial trade with China.
Introduction: This study examined the impact of the Agricultural Credit Scheme Fund (ACGSF) on agricultural output in Nigeria for the period 1981 to 2012. The study focused on the ACGSF loans granted to cash crop and livestock production subsectors and examined the impacts of these loans on the level of the outputs of each subsector. The order of the integration of the variables was tested using Augmented Dickey Fuller (ADF) and Philips-Perron (PP) unit root tests. The Johansen cointegration technique was also used to test the existence of a long run relationship between the variables. The regression results revealed an insignificant impact of loans to cash crop and livestock production on the level of outputs probably due to the misappropriation of the funds. The study concludes that the disbursement of the loans should be properly monitored by the ministry of agriculture to boost production in the sector.
Introduction: Human Capital Development and Economic Growth in Developing Countries: Further Empirical Evidence from Nigeria.
Introduction: Intra-regional Trade in WAEMU: An Empirical Study’, West African Journal of Monetary and Economic Integration
Introduction: Determinants of a Successful Regional Trade Agreement in West Africa
Introduction: The misconception of services as being non-productive has led to the neglect of the service sector in both economic
theory and applied economic researches. The Nigerian economy highly depends on the oil sector to generate revenue for the entire economy. This study examines the response of economic growth to the dynamics of the service
sector in Nigeria from the windows of governance indicators. Using annual data series, endogenous growth model,
and auto-regressive distributed lag technique, transportation and communication service sub-sector is significant and
positively related to economic growth. Health service sub-sector and transportation and communication sub-service
sector are significant and positively related to economic growth when governance indicators were accounted for.
Interaction of the sub-service sectors with governance indicators shows that none of the service sub-sectors were significant but were positively related to economic growth. The study shows that the activities of the education sub-sector have not contributed significantly to economic growth. Thus, for education to contribute positively to economic
growth there is a need for increase in budgetary allocation to education sub-sector. Efforts made to control corruption
and promote government effectiveness should be reviewed frequently to checkmate the processes of governance, so
that bureaucratic processes would not hinder services from contributing significantly to economic growth
Introduction: The problem of debt overhang is becoming intractable in Nigeria. It is believed that the rising trend of domestic debt is determined by some factors. The paper empirically investigates the variables influencing domestic debt.
Introduction: In this paper, we model the relationship between oil revenue and current account balance dynamics in Nigeria using quarterly data from 1987Q1 to 2015Q4. We employ both the Linear ARDL and Nonlinear ARDL models and we also account for multiple structural breaks using a test that allows for multiple structural changes in regression models. The following were noticed from our analyses. First, we observe the existence of an asymmetric effect on the current account balance both in the short and long run. Second, accounting for structural breaks play an important role when modelling the relationship between oil revenue and current account balance. Third, the paper finds that oil revenue has a significant positive effect on current account balance, however, puzzling that both positive and negative shocks affect the current account balance in the same manner. Overall, the positive changes in oil revenue have considerably larger impact than negative changes. The implications for policy are designed based on gathered findings.
Introduction: There is growing evidence that the gender distribution of wealth matters especially considering the fact that asset ownership is related to wellbeing, women empowerment and poverty alleviation. Not much is known about the gender distribution of wealth in the rural areas in Ogun state, Nigeria. This study assessed gender and asset distribution in Ogun State, South-west Nigeria using cross-sectional data collected from a total of 260 households selected through a five stage sampling procedure. The data were analysed using descriptive statistics and ordinary least squares multiple regression analysis. The findings from the study shows that an average rural household in the sample was made up of six persons and households were predominantly headed by males (88%). The mean worth of households’ physical assets was ?1,402,791.00, about 15% of which was owned by women. The ordinary least squares multiple regression analysis revealed that women’s share of assets had a positive influence (P<0.05) on the number of years of formal education completed by children below eighteen years. The education of father and mother were also significant at (P < 0.05) and (P < 0.01) respectively and these show that children have longer access to education when parents have at least secondary school education. Some identified constraints to women asset ownership in the study area were lack of capital (67%), domestic challenges (65%), cultural barriers to female inheritance (56%), and unemployment (52%). Based on these findings it is recommended that women should be encouraged to own more assets so as to be able to positively affect their children’s welfare in terms of education. The economic situation of women can be enhanced by promoting their access to productive assets through indigenous savings and credit associations. The rural households should further be exposed to awareness talks through extension agents stressing the values of education to all in our contemporary world
Introduction: Examination of the characteristics and causes of poverty is an important input into the design of economic policy and poverty alleviation programmes. This study assessed the poverty status of rural households in Ogun State, using the Asset Index Approach due to shortcomings of the conventional methods in poverty analysis. Relevant data were collected from a total of 260 households using a four-stage sampling procedure. The data were analyzed using principal component and ordered probit regression analyses (OPRA). The results showed that the OPRA, which significantly (?2 = 135.20, p < 0.01) explained the probability of a household escaping poverty, revealed that the primary occupation of household heads and the educational status of household heads and their wives among others factors significantly affect the likelihood of escaping poverty. The study therefore suggested that the economic situation of rural households can be considerably enhanced by promoting member’s access to qualitative education and also by encouraging household heads who take up farming activities as their primary occupation to participate in credit associations, indigenous savings and micro financing so as to boost their farming. Therefore, rural development policies should be tailored towards developing these facilities.
Introduction: This research work focused on the determinants of off-farm labour participation decisions of farm households in Oyo Agricultural Developmental Zone (OYSADEP). Primary data were used mainly for the study. Questionnaires were administered to 110 respondents and this was supplemented by oral interview. Data was analyzed using descriptive statistics and logit regression model. Findings from the study revealed that the major off-farm activities in the study area are petty trading (48.2%), hair dressing (13.6%), selling of musical records (8.2%), blacksmithing (6.4%), and hand crafts (5.5%). The reasons for off-farm labour participation of the respondents showed that 84.5% participated to complement their income from farming, 12.7% participated because of self-interest while 2.7% participated because of seasonality in most of the agricultural activities. Majority (54.5%) of the farm households earned less than N20,000.00 and the mean value of their income was N23,608.00 per month. The factors that influenced off farm labour participation within farm households in the study area are year of formal education (P<0.05) of the respondents, household size (P<0.05) of the respondents, total off farm income (P<0.01) and area of farm land cultivated (P<0.01). The study concludes that, farmers should be encouraged to take up offfarm labour works to serve as a risk mitigating strategy. Participation in off farm labour is capable of regulating farmer’s returns in a risky environment such as obtained in agricultural production.
Introduction: This article examines the evidence available on the distribution of assets by gender in rural households in Ogun State, Nigeria. One of the contributions of feminist economics has been to demonstrate
that household and individual welfare are not necessarily the same. Relatively very little work has
been done to show gender disparity in ownership of assets in rural Nigeria though gender asset distribution have been found to impact household decisions, women’s wellbeing and poverty alleviation.
Primary data was collected from a total of 260 households selected through a multistage sampling
procedure. The data were analyzed using descriptive statistics. The study finds that an average rural
household in the sample was made up of six persons and households were predominantly headed by
males (88%). The mean worth of households’ physical assets was ? 1,218,308.20, about 15% of
which was owned by women. Based on these findings the study recommends that the economic situation of women should be enhanced by promoting their access to productive assets through indigenous
savings, credit associations and micro financing. This will enable our society attain the sustainable
development goals of gender equality and maternal wellbeing.
Introduction: This study examined maternal and child dietary diversity within farming households in north western Nigeria;
specifically in Sokoto and Kebbi States. Primary data on personal and socio demographic characteristics of
subjects were collected in 1,500 households with the aid of a well pre-tested and structured questionnaire. Methods
of analysis used were descriptive statistics and dietary diversity score. Maternal and child dietary diversity scores
(DDS) were created based on mother’s recall of her own consumption of 9 food groups and her child’s
consumption of 7 food groups, during the 24 h prior to the home survey. Specifically, children within the age range
of 6- 23 months and women within the range of 15 – 49 years were considered based on the FAO recommendation.
Results revealed that 46.52% of children received minimum dietary component. The mean household dietary
diversity score (HDDS) was 5.42 while that of the women’s dietary diversity score (WDDS) was 4.29. Overall,
60.4% of the households had HDDS ? 5 while 39.6% had HDDS >5. The values for WDDS were 65.8% (? 4) and
34.2% (> 4). The proportion of HDDS < 5 and WDDS < 4 for Kebbi State was greater at 69.02 and 75.74%,
respectively. The study concludes that majority of the children and the women had low dietary diversity. The
proportion of households and women with low dietary diversity was greater in Kebbi State than what was obtained
in Sokoto State. The study therefore recommends that vigorous intervention through extension agents should be
made to women in the study area and especially in Kebbi State to create awareness about consumption of food in
the right quantity and quality to ensure maternal and child health in the farming households.
Introduction: This study examined the determinants of meat consumption among students of the Federal University of Agriculture, Abeokuta, Nigeria. Primary data on personal and socio economic characteristics of respondents were collected among 150 students with the aid of a pre-tested and structured questionnaire. Methods of analysis used were descriptive statistics, bar chart and multiple regression analysis. The results revealed about 69.3%of the respondents were within the age range of 18-24 years and majorities (56%) of the students interviewed were female. The average amount of income spent on meat consumption was N 1,904 per month while the amount spent on substitutes such as egg, snail and cow hides was N 147.90. The result of the distribution of students by total monthly income revealed that 27.3% of the students received below N 5001 per month while 58% of the students received an allowance between N5001 and N15000 per month. The result of the monthly expenditure of the students on various meat types distributed by sex in the study area revealed that beef accounted for the highest percentage of 24.4% of the monthly expenditure among female students while it constituted 24.0% of the males. On the other hand, pork accounted for 7.0% and 6.0% of total monthly expenditure on meat in male and female students respectively. The result further revealed that four variables exert significant influence on the consumption of meat in the study area. The age (X1) of the students was positive and significant at P <0.01. The student’s sex (X3), amount spent on substitutes(X5) and place of residence (X7) of students were negative and significant at (P < 0.05) and (P< 0.01) respectively. The study concludes that female students spend more on meat than their male counterparts. The amount of money spent on meat substitutes decreases with increase in meat consumption and students living off campus spend more on meat than students living on the campus. The study therefore recommends that processed beef in small units should be made available to students in the hostel and outlets close to students’ residential quarters to facilitate easy availability.
Introduction: Geographical information system was applied to map health facilities in Ogun State. The objective is to improve health care delivery in the state. Geographic coordinates of 1,141 health facilities across the 20 local governments were obtained and utilized to develop a Health Service Information Systems. Spatial database was constructed for all health facilities using information as ownership structure, number of personnel, capacities and building photographs. The facilities were categorized by spatial analysis into primary, secondary and tertiary health facilities; pharmaceutical, medical laboratories and traditional birth attendants. Analysis by ownership structure revealed that over 70% are privately managed while the other 30% were managed by either federal, state or local government authorities. Simpler medical services such as drug dispensary, maternity, pediatrics, family planning, immunization, dental, pharmaceutical and medical tests were provided by many of these health facilities, only very few could handle special services as surgery and other intricate medical services. The study revealed that the distribution of health facilities in the state is not equitable; they are rather clustered within urban areas and many people do not have direct access to good health services. Socioeconomic indicators also unveil the gross inadequacy of health facilities in all the local governments. The GIS maps indicates possible areas of locating new health facilities, it provides decision for geographical targeting of interventions for existing ones. The paper recommends particular attention to some identified towns in the construction of new health facilities in order to address inequality in health facilities distribution in the state.
Introduction: Mapping of Ofada Rice Production Areas for Value Chain Development in South – West Nigeria.
Introduction: Determinants of Rural Household’s Food Insecurity Status In Southwest Nigeria
Introduction: The study examined the effect of asset ownership on the poverty status of rural households in Ijebu-Ode Local Government Area of Ogun State, Nigeria. Multistage sampling technique was used to select 109 rural households in the study area. The study utilized primary data collected with the aid of well structure questionnaire. Data were analyzed using descriptive statistics, Principal Component Analyses (PCA), Asset Incidence, Foster-Greer-Thorbecke (FGT) poverty index, and the logit regression model. Asset Incidence results revealed that transport assets, followed by agricultural production assets, domestic assets and animal assets showed wide gender asset gaps in favor of men while productive assets shows a wide gender asset gap in favor of women.. FGT results showed that 59.6% of the respondents were poor while 40.4% were non poor. The result of the logit regression shows that poverty incidence reduced with asset ownership (p<0.01), and a higher level of income (p<0.01). The study therefore concluded that good percentages of the respondents were poor and that poverty level reduced with ownership of assets and increase in income. The study therefore recommends that rural households be sensitized on the importance of asset ownership and engaged in activities that will increase their incomes
Introduction: In the past, the idea was prevalent that wealth for some people in a population will translate into
wealth for all. Today, evidence reveals that there is a wide gap between the richest and the poorest in
most economies especially Nigeria. This study was conducted to estimate the determinants of wealth
status among rural and urban households in Nigeria. Secondary data and sample design used for this
study was adopted from the 2013 Nigerian Demographic and Health Survey (NDHS) carried out in
Nigeria. The sample used for the study was nationally representative and a total of 8658 households
were sampled from the six geopolitical zones in the country. The data were analyzed using descriptive
statistics, principal component and ordered probit models. Results revealed that about 67.4% of the
respondents reside in the rural areas. Majority of household heads were male and their mean age was
about 38 years.The result of the ordered probit model revealed that significant variables determining
wealth status in the study area are age of household head, type of place of residence, literacy, number
of years of education,and number of household dependents among others. Based on these findings, the
study recommends that interventions in terms of good quality education and other basic amenities
should be provided for people residing in the rural areas as rural people form the lion share of
respondents in the study area. The economic status of households can be improved through access to
productive assets through credit associations and indigenous savings
Introduction: The paper undertook an economic analysis of Ofada rice production in five prominent rice growing
areas of Ogun State. A two stage purposive sampling technique was employed to select a total of 120
rice farmers from five local government areas which are major areas known for Ofada rice production
in the state. Primary data were collected for the study through structured questionnaire and Focus
Group Discussion (FGD) among rice farmers groups in the study area. Analytical tools adopted for the
study included frequency, percentages, gross margin analysis and profitability ratios. Results of the
analysis showed that majority of Ofada rice producers in the study area are male (73.33%). In terms of
age, more than half of the respondents fell within the age range of 41 -50 years (63.33%) these farmers were young and within their active productive lives. Results of the distribution of respondents by
annual income in the study area revealed that majority of the respondents (60.83%) obtained an income of between ?201,000 and ?400,000.00 per hectare. However, 22.50% of the respondents
obtained an income of less than ?200,000.00 per hectare. The gross ratio, operating ratio, return per
naira invested and profitability index were calculated to be 0.95, 0.80, 1.90 and 1.80 respectively. The
gross margin of rice production per hectare was also estimated to be ?222,020.00. All these indicate
overall profitability of the enterprise. However, an average low yield of 2.5 tonnes per hectare was
recorded due to constraints encountered during production. Some of the identified constraints in the
study area are lack of capital (25.83%), lack of tractor for land clearing (10.83%), lack of good farm
roads (16.67%), and inadequate processing and storage facilities (11.67%). It is then recommended
that access to adequate capital, mechanical equipment and other incentives through farmers’ cooperatives and government aid for construction of farm roads could help increase rice production in the area
and this will in turn help Nigeria to achieve a much desired self-sufficiency in rice production.
Introduction: This study examined the pattern and determinants of asset ownership among farm households in Odeda local government area of Ogun State, Nigeria. Primary data were used for the study which was sourced via a three stage sampling technique. A total of one hundred and twenty farm households were selected. The study models were the principal component analysis, asset index and the ordinary least squares regression analyses. Results revealed that most of the respondents (84%) were less than 50 years, with a mean age of 42 years. Most of them (70%) had over 5 years of formal education. Domestic assets owned by the respondents were radio, refrigerator, transport assets and agricultural productive assets including agricultural land and real estate. Substantial gender disparity in asset ownership was revealed. Wide asset wealth gap in the value of assets accruing to men was higher than that to the women. Inequality was highest for real estate and agricultural land, with an asset wealth gap of 0.32:0.06 and 0.41:0.10 respectively. The pattern of asset ownership showed that television had the highest scoring factor of 0.728 while grinding machine had the least scoring factor of -0.260. The result of regression analysis showed that age (p<0.01), gender (p<0.05), marital status (p<0.01), household size (p<0.10) and education (p<0.01), were the major factors influencing asset ownership among farm households in the study area. The study therefore recommends the need to avail farm households’ access to productive assets through micro financing, savings and credit associations’ activities. There is need to improve the level of education among the rural household heads. Government on its part should enable policies targeted at enhancing women literacy and their access to productive assets.
Introduction: This paper investigates the effectiveness of sovereign wealth funds (SWFs) in reducing macroeconomic volatility occasioned by oil price shocks in oil?exporting African countries. The oil price boom?bust cycles complicate fiscal operations, distort budget implementation and trigger macroeconomic instability in oil exporting African countries. We formulate and simulate a dynamic stochastic general equilibrium model that features SWFs and the fiscal sector. We compare a baseline model without the SWFs to a model with the SWFs. The simulation analysis suggests that the establishment of SWFs can mitigate the vulnerability of oil?exporting African countries to oil price shocks. In particular, SWFs can reduce fiscal expenditure and real exchange rate volatility. Furthermore, SWFs can stabilise the level of external debt and reduce the level of money supply thereby sterilising the oil revenue. Since oil price shock is one of the important external shocks inducing economic instability in oil?exporting African countries, the creation of SWFs can insulate these economies from external shocks.
Introduction: The study investigates the effects of external shocks on economic growth dynamics in Nigeria. We employ structural vector autoregression (SVAR) technique. We consider six external shocks- external debt, foreign interest rate, foreign output, oil price, foreign input price and real interest rate shocks. Our findings indicate that external shocks impact economic growth in Nigeria. Among the external shocks, we find that foreign interest rate shocks, foreign input price shocks and external debt shocks are the most important shocks impacting economic growth in Nigeria. The importance of foreign interest rate shocks and foreign input price shocks suggest the significance of external financial shocks and foreign supply shocks on economic growth in Nigeria. The findings, however, show that oil price shocks, foreign output shocks and real exchange rate shocks have limited impact on economic growth in Nigeria.
Introduction: This paper develpos and estimates a small open economy dynamic stochastic genral equilirium (DSGE) model for the Nigerian economy using the Bayesian technique. We include a number of frictions, rigidities and shocks in our model. The results show a considerable evidence of price stickiness in Nigeria. Furthermore, the results suggest that the forward-looking component dominates price setting behaviour in Nigeria. Moreover, the findings indicate that external shocks such as external debt, exchange rate and foreign inflation shocks largely influence output fluctuation in Nigeria while inflation is driven by money supply, productivity, nominal exchange rate and domestic interest rate shocks. Lastly, the findings indicate that the monetary authority responds strongly to real exchange rate shocks.
Introduction: This paper estimates a New Keynesian Phillips curve (NKPC) model for the Nigerian economy. This is to identify the structural parameters determining inflation dynamics in Nigeria. Previous studies that examined the dynamics of inflation in Nigeria have largely estimated the traditional Phillips curve. This study employs quarterly time series data on six macroeconomic variables from 1990:1 to 2012:4. The study adopts the Generalized Method of Moments (GMM) technique to analyse the data. The findings indicate that both backward-looking and forward-looking behaviour are significant determinants of inflation dynamics in Nigeria. The results, however, suggest that backward-looking behaviour seems to be more quantitatively important in inflation dynamics. Moreover, the findings indicate that price of foreign input, money supply and the lending rate are the main drivers of inflation in Nigeria.
Introduction: We estimate a monetary DSGE model to examine the role of macroeconomic shocks in generating fluctuations in ten African countries. The model is estimated with the Bayesian technique using twelve macroeconomic variables. The findings indicate that both the internal and external shocks significantly influence output fluctuations in African economies. Over a four quarter horizon, internal shocks are dominant and over eight to sixteen quarter horizons, external shocks are dominant. Among the external shocks, external debt, exchange rate, foreign interest rate and commodity price shocks account for a large part of output variations in African economies. Money supply and productivity shocks are the most important internal shocks contributing to output fluctuations in African countries.
Introduction: The paper examines the role played by banks in the propagation of external shocks to African economies. We employ a general equilibrium model of a small open economy to analyse how the banking sector propagates external shocks. The study uses a vector autoregression (VAR) analysis to assess the impact of exchange rate and foreign interest rate shocks on bank lending spreads and output fluctuations in African economies. We use quarterly time-series data for 5 selected African countries for the period 1990-2011. The findings show that foreign interest rate and exchange rate shocks significantly affect output fluctuations in Africa. The results, however, indicate that banks play limited role in the propagation of shocks to African economies.
Introduction: Dataset for Electronic Payment Performance in Nigerian Banking System: A trend Analysis from 2012 to 2017.
Introduction: Dataset for Electronic Payment Performance in Nigerian Banking System: A trend Analysis from 2012 to 2017.
Introduction: An Evaluation of Agricultural Financing Policies and Initiatives for Sustainable Development in Nigeria, In the 21st Century: 1990-2014
Introduction: Financing Agriculture as a Way of Diversification of Nigerian Economy: Challenges and Prospects.
Introduction: This paper focuses on the return and volatility spillovers among the major agricultural commodities in Nigeria. Specifically, we examine the spillovers across wheat, rice, soybeans, groundnut and palm oil both in terms of returns and volatility using monthly data from January 1980 to June 2017. We employ the Diebold and Yilmaz (2012) spillover approach and consequently, we compute the Total Spillover, Directional Spillover and Net Spillover indices. In a bid to capture the inherent secular and cyclical movements in the Nigerian agricultural commodities market, we carry out the rolling sample analysis which complements the spillover results. We find evidence of interdependence among major agricultural commodities in Nigeria given the spillover indices. Interestingly, return and volatility spillovers exhibit both trends and bursts respectively. In addition, we recognize crisis periods that seem to have motivated the documented fluctuations in returns and volatilities of the Nigerian agricultural commodities market. Our results are robust to the VAR lag structure.
Introduction: This paper measures the return and volatility spillovers of crude oil and food prices in Nigeria using the Diebold and Yilmaz (2012) approach. It utilizes the monthly data of food prices and crude oil from January 01 1997 to June 30, 2017. This study also carries out rolling sample analyses to capture secular and cyclical movements in oil and food markets. The paper finds evidence of interdependence among crude oil and food prices based on the spillover indexes. In addition, the returns spillover exhibits trend but no burst while the volatility spillover exhibits both trend and burst over the period under consideration. By understanding the mechanisms behind these dynamics, better policy measures could be put in place to optimize and stabilize the markets. Finally, the results are robust to the VAR lag structure and rolling window width.
Introduction: This paper examines the return and volatility spillovers of different sectoral stock prices in Nigeria using monthly data from January 2007 to December 2016. We employ the Diebold and Yilmaz (2012) spillover approach and rolling sample analysis to capture the inherent secular and cyclical movements in the sector stocks market.We show that there is substantial difference between the behaviour of the sectoral stock return and volatility spillover indices over time. We find evidence of interdependence among sector stocks given the spillover indices. While the return spillover index reveals increased integration among the sectoral stocks, the volatility spillover index experiences significant bursts during major market crises. Interestingly, return and volatility spillovers exhibit both trends and bursts respectively
Introduction: This paper aims to model the relationship between oil price and six major agricultural commodity prices using monthly data from January 1997 to December 2016.
Introduction: Volatility Transmission in the Nigerian Financial Market.
Introduction: Determinants of Food Price Volatility in Nigeria.
Introduction: This study examines the dynamic relationship between oil revenue, government spending and economic growth in Nigeria. Since the discovery of oil, oil proceeds have dominated the country's federation account and have improved public spending. In this paper, we analyse if the huge government spending has improved the rate of economic growth. To do this, the multivariate vector autoregression framework with special attention to Generalised Impulse Response Function is adopted in analysing the annual data of oil revenue, total government expenditure and real Gross Domestic Product from 1980 to 2015. We find evidence that oil receipts remain the major route which public spending is financed and the fundamental source for growth. Hence, there is need for the government to diversify the sources of foreign exchange inflow of the country. The diversification of the economy is required to insulate it from external shocks. It is recommended for Nigeria to explore ways of reviving its huge agricultural potential which has been neglected since the discovery of oil in addition to exploring its rich untapped solid minerals deposit in order to promote diversification of the economy away from a mono cultural product base.
Introduction: This paper examines the return and volatility spillovers of different sectoral stock prices in
Nigeria using monthly data from January 2007 to December 2016. We employ the Diebold
and Yilmaz (2012) spillover approach and rolling sample analysis to capture the inherent
secular and cyclical movements in the sector stocks market.We show that there is substantial difference between the behaviour of the sectoral stock return and volatility spillover
indices over time. We find evidence of interdependence among sector stocks given the spillover indices. While the return spillover index reveals increased integration among the
sectoral stocks, the volatility spillover index experiences significant bursts during major
market crises. Interestingly, return and volatility spillovers exhibit both trends and bursts
respectively.
Introduction: This paper examines the Balance-of-Payment (BOP) constraint growth model in Nigeria for the period of 1980 to 2012 using the bounds testing Auto regressive Distributed Lag (ARDL) approach. The ARDL test suggests that the variables in the framework have a long run relationship. The empirical findings reveal that import is cointegrated with relative price and income, and the equilibrium growth rates coincide with actual growth rates, hence, the result shows that the Thirlwall’s law, of actual growth rate being equal to the predicted growth rate by the balance of payment current account equilibrium holds in Nigeria. This reason may be due the fact that the economy of Nigeria depends mainly on international trade even though oil dominates the export. This Thirlwall’s BOP-constrained growth approach provides some significant policy prescriptions for Nigeria’s development policy. Achievement of potential growth can be stimulated by making exports more competitive through macroeconomic stability, sound institutional qualities, improvement in human and physical capital development, reducing access problems to external market, among other factors.
Introduction: This paper examines the Balance-of-Payment (BOP) constraint growth model in Nigeria for the period of 1980 to 2012 using the bounds testing Auto regressive Distributed Lag (ARDL) approach. The ARDL test suggests that the variables in the framework have a long run relationship. The empirical findings reveal that import is cointegrated with relative price and income, and the equilibrium growth rates coincide with actual growth rates, hence, the result shows that the Thirlwall’s law, of actual growth rate being equal to the predicted growth rate by the balance of payment current account equilibrium holds in Nigeria. This reason may be due the fact that the economy of Nigeria depends mainly on international trade even though oil dominates the export. This Thirlwall’s BOP-constrained growth approach provides some significant policy prescriptions for Nigeria’s development policy. Achievement of potential growth can be stimulated by making exports more competitive through macroeconomic stability, sound institutional qualities, improvement in human and physical capital development, reducing access problems to external market, among other factors.
Introduction: Empirical work on modelling stock price volatility in the agro-allied sub-sector of the Nigerian Stock Exchange is scarce despite the importance of agriculture to the Nigerian economy, the need to encourage investment in the sector and the importance of volatility patterns to investment decision. This study modelled conditional variances (volatility) of specific but well-known agro-allied companies in Nigeria using daily closing prices from 1st September, 2015 to 31st August, 2016. The study adopted both the symmetric and the asymmetric modifications of the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) model to model the series’ volatilities. The results showed no evidence of leverage effects on stock prices except in the case of two firms and therefore based on the appropriate model selection criteria, the symmetric models appeared to be superior to the asymmetric models. It was concluded that investors needed to consider the nature and characteristics of stock price behaviour when taking investment decisions. In addition, policy makers should be careful not to make statements with potential to generate bad news for the capital market. The regulatory agencies should continue to strengthen measures to develop the capital market in order for it to be resilient and able to cope better with bad news when they occur. Finally, more research, based on a wide variety of alternative models is called for to produce more empirical evidence on volatility especially in the agro-allied sector of the Nigerian capital market.
Introduction: In the Nigerian economy using monthly time series data over the period January 2008 to May 2017. The short-run and long-run asymmetries were analysed using nonlinear autoregressive distributed lags (NARDL) framework. The empirical results suggest the presence of cointegration as well as asymmetric relations. Specifically, positive changes in oil price tend to have no significant effect on the Nigerian stock performance. This paper examines the asymmetric effect of oil price shocks on stock market performance. However, negative developments turned out to have positive and significant effect on stock performance in both the long and short runs. This implies the need for the regulatory agency to continue to strengthen its effort aimed at promoting the development of the capital market and making it better able to cope with external shocks such as adverse movements in crude oil prices. The current efforts of the SEC in spearheading the implementation of the capital market master plan are part of such measures. Fresh data when it is available is therefore required to enable newer research to gauge whether or not these efforts by the SEC are making the market more resilient to falls in crude oil prices on the world market.
Introduction: This study compares the performance of GARCH-Type models in
modelling inflation volatility in Nigeria covering the period 1995M01 to
2016M10. In the paper, we provide two main innovations: (i) we analyze
inflation rate of two pronounced consumer prices indices namely
headline and core consumer price indices using the Augmented DickeyFuller break point test which allow for structural breaks in the data
series; and (ii) the method is modified to include both symmetric and
asymmetric volatility models. The empirical examination observes
evidence of volatility persistence in the consumer price indices, but only
headline is consistent with leverage effects. Thus, applying one-modelfits-all approach as well as discarding the role of structural breaks for
inflation rate volatility in Nigeria will yield misleading and invalid
policy prescriptions
Introduction: This paper examined the fiscal response of government to oil price volatility in Nigeria during the period 1970-2013. This is because no study has analysed the peculiar fiscal behaviour of the government given the unpredictable nature of oil prices. Yet, government fiscal activities had significantly determined and shaped the growth path of the economy. The multivariate vector Auto regression model was explored for the empirical analysis. Our findings showed that real oil prices had driven government expenditure dynamics and a long run relationship between real oil prices and government spending, non-oil growth, inflation and discount rate differential exist; and no asymmetric effect of oil price shocks on the government spending. However, these results are robust to different non-linear transformation of the real oil prices and inclusion of additional variables. Since oil price is highly volatile, it is advised that the government diversify the sources of foreign exchange inflows.
Introduction: The theoretical obligation of the managers in the agency theory is to safeguard the interest of the shareholders, and this study is targeted at investigating the impact of corporate governance on the performance of nine selected banks in Nigeria. The study performs a pooled Ordinary Least Square (OLS) regression analysis of the data from 2006 to 2010. The findings suggest that both size of the board and its ownership structure have positive significant effects on the Return on Equity (ROE). However, the influence of governance indicator on the assets of the companies is significantly negative. Further, the board composition is found to be insignificant as a predictor of profitability measures. The regulatory influence and economic conditioning factors also show no significant effect on Return on Assets (ROA) as well as ROE, suggesting that the banks have developed the ability to absorb or conceal domestic shocks in the economy. The results generally support the hypothesized fact that the banking industry suffers from asset management and poor governance malaise. The study recommends that the regulatory authorities, including the Asset Management Company of Nigeria, be involved in the screening and monitoring of debt assets beyond the current salvage practice.
Introduction: This paper analyzes the fiscal response of the government to aid inflows in Nigeria during the period 1961 to 2009. This is against the backdrop of the fact that no study has analyzed the peculiar fiscal response/behavior of the government in Nigeria vis-à-vis aid flow over time. Yet, the fiscal response of the government had significantly determined and shaped the growth path of the economy. The empirical analysis is anchored on the Heller type fiscal response modeling analytical framework and combines several procedures in modern econometric analysis/estimation techniques. The findings show that aid inflows had significant impact on the fiscal reactions of government in Nigeria: government expenditure, particularly capital (development) expenditure, increased in response to aid flows, tax efforts were relaxed, while domestic borrowing declined. Aid flows also provide free resources to increase recurrent (routine) spending, thus confirming the aid fungibility hypotheses. Since aid inflows cannot be permanently relied upon, it is advised that the government place a premium on improving its tax efforts as well as cut down recurrent expenditures.
Introduction: This paper examines the relationship between capital market development and Nigeria's economic growth using data covering the range of 1981 to 2010 using a Johansen Cointegration technique to test for long run relationship among the variables under study. The empirical findings from the research work suggest that the capital market is on the average and beneficial to the economy. However, the high costs of raising capital and structural imbalances in the market as well as inconsistent government policies may distorts the speedy growth of the market and thus, limit its positive impact on the economy.
Introduction: In this paper, we provide two main innovations: (i) we analyze oil prices of two prominent markets namely West Texas Intermediate (WTI) and Brent using the two recently developed tests by Narayan and Popp (2010) and Liu and Narayan, 2010 both of which allow for two structural breaks in the data series; and (ii) the latter method is modified to include both symmetric and asymmetric volatility models. We identify two structural breaks that occur in 1990 and 2008 which coincidentally correspond to the Iraqi/Kuwait conflict and the global financial crisis, respectively. We find evidence of persistence and leverage effects in the oil price volatility. While further extensions can be pursued, the consideration of asymmetric effects as well as structural breaks should not be jettisoned when modelling oil price volatility.
Introduction: This study examines the effect of oil discovery on sectoral performance in Nigeria, using the time series data from 1975 to 2010. The empirical analysis rests on the Dutch Disease (DD) hypothesis and also combines several procedures in modern econometric estimation techniques. The findings show that oil discovery in Nigeria affects both the agricultural and industrial sectors. However, the effect on the agricultural sector is larger than that on the industrial sector, thus, confirming the existence of DD in Nigeria. The study therefore recommends that the government should give priority to the agricultural sector through the provision of infrastructures, incentives in the form of subsidies, and general modernization of agricultural activities.
Introduction: This paper examines the impact of oil price movements on real output growth in Nigeria during the period 1970 to 2011 making use of annual time series data. The empirical analysis rests on dynamic VAR analytical framework. To capture the possible channels reflecting the fluctuations in the oil prices, the model includes money supply, real exchange rate, government spending and inflation. Our findings indicate the lagged effects of the VAR model are not able to capture any significant impact of changes in oil prices, and oil price shocks are therefore not found to contribute directly to output, exchange rate or inflation in the short run but show a positive significant relationship to output growth in the long run. Following the VAR model results, the generalized impulse responses reaffirm the direct link between the net oil price shock and growth, as well as the indirect linkages.
Introduction: The inflexibility of poverty is being met with increasing impatience from governments of diverse ideologies, donors and other international agencies. Recent data compilations show that many poor and non-poor people in many developing countries face a high degree of financial exclusion and high barriers in access to finance. Therefore, financial inclusion plays a critical role in reducing poverty. Hence, this paper examines the relationship between sustainable financial services and poverty reduction in Nigeria from 1965 - 2010 using Error Correction Model (ECM). It was observed that total value prime lending rate, financial savings, credit to private sector and rate of inflation all have significant impact on the financial deepening. In the final analysis, the study concludes that financial inclusion tends to strengthen financial deepening and provide resources to the banks to expand credit delivery thereby leading to financial development. The study therefore recommends that these findings, in turn, will inform the policy makers and stakeholders to build more inclusive financial systems
Introduction: his study examines the impact of financing small scale enterprises on economic growth in Nigeria, using a quarterly time series data from 1992 to 2009. The study combined several econometric estimation techniques. The findings shows that loan to small scale entrepreneurs have a positive impact on the economic performance while interest rate has a negative impact on economic growth. The study thereby concludes that the greatest or worst problem confronting SMEs in Nigeria is managerial capacity. Access to capital or finance is necessary but not a sufficient condition for successful entrepreneurial development.
Introduction: This study examines the impact of monetary policy on economic growth in Nigeria.The study uses time-series data covering the range of 1975 to 2010.The effects of stochastic shocks of each of the endogenous variables are explored using Error Correction Model (ECM). The study shows that Long run relationship exists among the variables. Also, the core finding of this study shows that inflation rate, exchange rate and external reserve are significant monetary policy instruments that drive growth in Nigeria .It is therefore recommended that the establishment of primary and secondary government bond markets that can also increase the efficiency of monetary policy and reduce the government’s need to rely on the central bank for direct financing.
Introduction: This paper examines the impact of Corporate Social Responsibility (CSR) on Financial
Performance of Firms in Nigeria. This study utilizes both primary and secondary data. The questions
were structured in such a way as to gather pertinent and specific information on how effective
Corporate Social Responsibility (CSR) has improved the financial viability of firms in Nigeria. This
paper employs both descriptive and quantitative techniques in which chi-square technique and content
analysis was used to test the significance relationship among the frequencies. The study reveals that
proper and effective CSR goes a long way in improving the trend of firms’ financial performance in
Nigeria using Cadbury Nigeria Plc. as the study area. It was observed that CSR could be a key
instrument to the financial development of any organizations through the process of giving back to
the community.
Introduction: Public Expenditure and Economic Growth in Nigeria: Evidence from Auto-Regressive Distributed Lag (ARDL) Specification
Introduction: This paper examines the concept of micro credit as a tool for alleviating poverty in Nigeria. Micro credit is about providing
specialized credit savings and other financial services of small amount to micro entrepreneurs to enable them expand their
business opportunities, increase their income and their living standards. This study utilizes primary data that were obtained
through the use of structured questionnaires. The questions were structured in such a way as to gather pertinent and specific
information on how micro credit has enhanced the quality of life of rural dwellers of the Ijebu North Local Government Area
of Ogun state, Nigeria. This paper employs both descriptive and quantitative techniques in which chi-square technique was
used to test the significance difference among the frequencies. The findings indicate that micro credit to some extent
enhances the general welfare of rural dwellers thereby reducing the level of poverty in the economy if they are properly
financed and managed.
Introduction: : In this paper, we compare the performance of volatility models for oil price using daily
returns of WTI. The innovations of this paper are in two folds: (i) we analyse the oil price across three
sub samples namely period before, during and after the global financial crisis, (ii) we also analyse the
comparative performance of both symmetric and asymmetric volatility models for the oil price. We
find that oil price was most volatile during the global financial crises compared to other sub samples.
Based on the appropriate model selection criteria, the asymmetric GARCH models appear superior to
the symmetric ones in dealing with oil price volatility. This finding indicates evidence of leverage
effects in the oil market and ignoring these effects in oil price modelling will lead to serious biases and
misleading results
Introduction: This paper examines the impact of informal sector on employment generation in Nigeria during the period 1970 to 2010 making use of annual time series data. The empirical analysis rests on the augmented Solow growth analytical framework. Our findings show that informal sector activities have significant impact on absorbing the large pool of labour force in Nigeria. The study contends that human capital formation is positively related to unemployment rate which reflects the dearth of government expenditure on education in the country. Therefore, there is an urgent need for the government to re-examine its policies on informal sector.
Introduction: This paper analyses the impact of foreign aid on economic growth in Nigeria during the
period of 1970-2010. The empirical analysis rests on the neo-classical modelling analytical framework
and combined several procedures in modern econometric analysis/estimation techniques. Our findings
shows that aid flows has significant impact on economic growth in Nigeria: domestic investment
increased in response to aid flows and population growth has no significant effect on aid flows. Aid
flows also provides free resources to increase domestic investment, thus confirming the aid-policygrowth hypothesis. Therefore, donor governments should be aware of the political situations in
recipient countries, and work with international bodies to ensure as much stability as possible. Finally,
foreign aid transfers should henceforth pledge to abide by the oath to of doing no harm
Introduction: This study examines the impact of trade openness on manufacturing sector performance in Nigerian economy, using a times series data from 1975-2010
Introduction: This paper examines how social or communal norms determine masculinities in some of Chinua Achebe's and Buchi Emecheta's novels.
Introduction: This paper, "Masculinities and Authority: Who has Authority in the Home?" examines the concept of authority as the key area in Masculinities
Introduction: This paper argues that one's dignity as "masculine" and access to the competence and prerogatives associated with it are contingent upon the justification of male peers.
Introduction: Half Heusler alloys are among the most studied materials because of their high performance as thermoelectric materials. In view of this, we present electronic and thermoelectric properties of RhTiP. In this work, DFT-GGA(PBEsol) was used to obtained lattice constant and electronic band structure and Elastic properties. Semi-classical Boltzmann theory was used to obtain the Seebeck coefficient, electrical conductivity, power factor, and electronic fitness function. The lattice constant of RhTiP is 5.69
Å
, and the band structure shows that RhTiP has an indirect bandgap of 0.83 eV. The Elastic properties predict the mechanical stability of RhTiP. The Seebeck coefficient of 368.23 ?V/K and power factor of 0.51 mW/m at 800 K are obtained from this calculation, Electronic Fitness Function of 1.13 is obtained at 800 K. From our results, it shows that RhTiP is a good thermoelectric material.
Introduction: Huge attention has been shifted to thermoelectric properties of half-Heusler compounds because of the ability of these compounds to convert heat into electricity. The calculations of thermoelectric properties of these compounds are necessitated by the search for alternatives to fossil fuel. This report presents ab initio calculations of electronic and thermoelectric properties of the most stable phase of hafnium–rhodium-based arsenic, antimony and bismuth (HfRhZ(Z = As, Sb and Bi)) half-Heusler compounds by density functional theory based on projector augmented wave pseudopotential method with Perdew–Burke–Ernzerhof generalized gradient approximation used for exchange–correlation functional. The properties calculated in this work are the equilibrium lattice constant, the density of states, band structures, Seebeck coefficients, electrical conductivity, power factor and electronic fitness function (EFF). EFF is calculated to overcome the problem of optimizing Seebeck coefficient and electrical conductivity because of inverse proportion relationship between Seebeck coefficient and electrical conductivity. The ? phase of these compounds is found to be most stable, and thus, electronic and thermoelectric properties of this phase are obtained for the p-type HfRhZ( Z = As, Sb and Bi). The p-type HfRhZ(Z = As, Sb and Bi) is a better thermoelectric material than the n-type HfRhZ(Z = As, Sb and Bi). The Seebeck coefficients of these compounds are 272.01 ?V/K, 555.75 ?V/K and 244.92 ?V/K for HfRhAs, HfRhSb and HfRhBi, respectively, and EFF of HfRhAs, HfRhSb and HfRhBi is 1.21×10?19W5/3ms?1/3K?2 at 1.75×1020cm?3, 1.55×10?19W5/3ms?1/3K?2 at 1.64×1020cm?3 and 1.07×10?19W5/3ms?1/3K?2 at 4.50×1020cm?3, respectively. The results obtained in this work show that HfRhSb and HfRhAs are better potential thermoelectric materials than some known high-performance thermoelectric materials.
Introduction: In this work, details density functional theory calculations were performed to obtain the electronic, elastic, phonon and thermodynamic properties of half-Heusler alloys HfNiX (X = Ge and Sn). The PBE functional as implemented in Projector augmented-wave (PAW) pseudopotentials was used for all the calculations. From our results, we reported the energy gap of 0.38 eV for HfNiSn and 0.61 eV for HfNiGe indicating the semiconductor property of these compounds. Also, the mechanical and elastical stabilities of these compounds were confirmed from the comparison of the elastic constants of these compounds with conditions for stabilities. Although the phonon dispersion curves for HfNiGe and HfNiSn are similar with splitting at the ? point, the shift in their frequency was as a result of the mass different in Ge and Sn. The phonon dispersion curve predicts the dynamically stabilities of these half-Heusler alloys. From the thermodynamic properties of these compounds, it was revealed that these compounds are soft at low temperature, but at a high temperature they tend to be hard materials. Our calculations showed that these two compounds are mechanically, elastically and dynamically stable as cubic half-Heusler alloys.
Introduction: Detailed first-principle calculations of properties in zinc blende quaternary alloy BxAlyIn1?x?yN at various concentrations are investigated using density functional theory (DFT) within virtual crystal approximation (VCA) implemented in alchemical mixing approximation. The calculated bandgaps show direct transitions at ?–? and indirect transitions at ?–X, which are opened by increasing boron concentration. The density of state (DOS) revealed upper valence band (VB1) domination by p-states atoms, while s-states dominate the lower valence band (VB2); also, the DOS shows the contribution of d-states to the conduction band. The first critical point in the dielectric constant ranges between 0.07–4.47 eV and is due to the first threshold optical transitions in the energy bandgap. Calculated static dielectric function (DF) ?1(0) is between 5.15 and 10.35, an indication that small energy bandgaps yield large static DFs. The present results indicate ZB-BxAlyIn1?x?yN alloys are suitable candidates of deep ultraviolet light emitting diodes (LEDs), laser diodes (LDs) and modern solar cell since the concentrations x and y make the bandgap and lattice constant of ZB-BxAlyIn1?x?yN quaternary alloys tunable to desirable values.
Introduction: We present first-principle calculations of structural, electronic, and optical properties of zinc-blende (z) BxAlyGa1-x-yN quaternary alloy, using alchemical mixing of plane-wave pseudopotentals method based on density functional theory (DFT). Generalized gradient approximation (GGA) is used to describe exchange–correlation potential coupled with the Perdew, Burk and Ernzerhof (PBE) flavour. The calculated structural properties, equilibrum lattice constant and bulk modulus are in excellent agreement with available theoretical and experimental data. The bandgaps obtained depend on alloying concentrations x and y. The bandgap and density of states (DOS) are in good agreement with available theoretical data. The optical spectra obtained are given in the energy range of 0–8?eV. The results obtained in this calculation indicate that BxAlyGa1-x-yN alloy is a desirable material for manufacturing of deep ultraviolet (UV) light emitting diodes (LEDs) and laser diodes (LDs).
Introduction: First principle calculations have been performed to obtain detailed electronic structure, optical functions and optical properties of BCC . Frequency dependent dielectric matrix was employed in the determination of imaginary part of the dielectric function from which the real part has been obtained through the use of Kramers–Kronig (KK) relations. The calculated optical constants of show an indirect band gap at 0.41 eV, while critical points are observed at 2.25, 2.94 and 5.93 eV. Other optical properties like optical conductivity, absorption coefficient and reflectivity were also determined.
Introduction: E. coli O157:H7 is a foodborne pathogen that constitutes a global threat to human
health. However, the quantification of this pathogen in food and environmental samples may
be problematic at the low cell numbers commonly encountered in environmental samples. In this
study, we used recombinase polymerase amplification (RPA) for the detection of E. coli O157:H7,
real-time quantitative PCR (qPCR) for quantification, and droplet digital PCR (ddPCR) for absolute
and accurate quantification of E. coli O157:H7 from spiked and environmental samples. Primer and
probe sets were used for the detection of stx1 and stx2 using RPA. Genes encoding for stx1, stx2, eae,
and rfbE were used to quantify E. coli O157:H7 in the water samples. Furthermore, duplex ddPCR
assays were used to quantify the pathogens in these samples. Duplex assay set 1 used stx1 and rfbE
genes, while assay set 2 used stx2 and eae genes. Droplet digital PCR was used for the absolute
quantification of E. coli O15:H7 in comparison with qPCR for the spiked and environmental samples.
The RPA results were compared to those from qPCR and ddPCR in order to assess the efficiency of the
RPA compared with the PCR methods. The assays were further applied to the dairy lagoon effluent
(DLE) and the high rate algae pond (HRAP) effluent, which were fed with diluted DLE. The RPA
detected was <10 CFU/mL, while ddPCR showed quantification from 1 to 104 CFU/mL with a high
reproducibility. In addition, quantification by qPCR was from 103
to 107 CFU/mL of the wastewater
samples. Therefore, the RPA assay has potential as a point of care tool for the detection of E. coli
O157:H7 from different environmental sources, followed by quantification of the target concentrations.
Introduction: Abstract
Background and Objective: A comparative study was carried out on the effect of phytohormone on seed germination, seedling vigour
and the phytochemical content of three cucurbits, which are Cucumis melo (L.), Lagenaria breviflora (Benth) and Citrullus lanatus
(Thunb). Phytochemical analysis of air-dried, powdered epicarp, mesocarp and seeds of the mature fruits were carried out, also the effects
of varying concentrations of indole acetic acid (IAA), naphthalene acetic acid (NAA) and gibberellic acid (GA3) on germination and seedling
vigour of these 3 cucurbits were investigated. The study is designed to obtain the inhibitory and the stimulatory effects of the
3 cucurbits used in this research. Materials and Methods: Treatments were arranged in 5 replicates and monitored for 16 days.
Experiments were carried out in 9 cm petri dishes in the laboratory. Data were subjected to two-way analysis of variance (ANOVA) at
p<0.05. Means were compared using LSD. Results: The study revealed that the mean percentage germination and seedling vigour
of Cucumis melo (C. melo) was significantly higher (p<0.05) in the control than in 100-500 ppm concentrations of GA3, IAA and NAA.
Phenol was not detected in the epicarp and mesocarp of C. lanatus and seeds of L. breviflora. However, concentrations of phenol detected
in the different parts of C. melo and Lagenaria breviflora (L. breviflora) (epicarp, mesocarp and seed) were not significantly different. The
concentrations of the phytochemicals were significantly (p<0.05) different among the epicarp, mesocarp and seeds of the cucurbits except
for alkaloid. However, concentrations of phenol detected in the different parts of C. melo and L. breviflora were not significantly different
(p>0.05). Tannin was not detected in the epicarp, mesocarp and seeds of the three cucurbits. Flavonoid was also significantly higher
(p<0.05) in the epicarp of C. melo and L. breviflora than in their mesocarp and seeds. Conclusion: Conclusively, effects of varying
concentrations of IAA, NAA and GA3 was not significant on the parameters studied. Phytochemicals were detected in the epicarp,
mesocarp and seeds of the cucurbits under investigation. This study revealed
Introduction: A comparative study was carried out on the nutritional contents of the seeds and fruits of Cucumis melo (L.),Lagenaria breviflora (Benth) and Citrullus lanatus (Thunb). Proximate composition, Vitamin C content and phytochemical analysis of air-dried, powdered epicarp, mesocarp and seeds of the mature fruits were also carried out using standard procedures. Data on nutritional and phytochemical characteristics were collected andsubjected totwo - way analysis of variance (ANOVA)at p<0.05. Means were compared using LSD.Total sugar and vitamins C were detected in the other parts of the fruits except the seeds in the three Cucurbits. Percentage dry matter, fat, ash and crude protein were significantly (p<0.05) higher in the seeds than in the epicarp and mesocarp. Crude fibre was highest in the epicarp for C. melo(1.75 0.13), L. breviflora (1.85 0.07)and C. lanatus (2.18 0.07).
Introduction: A comparative study was carried out on the phytochemical cotent of the seeds and fruits of Cucumismelo(L.),
Lagenariabreviflora(Benth) and Citrulluslanatus(Thunb). Phytochemical analysis of air-dried,
powderedepicarp, mesocarp and seeds of the mature fruits were carried out using standard procedures. Data
on phytochemical characteristics were collected andsubjected totwo - way analysis of variance (ANOVA)at
p<0.05. Means were compared using LSD. Phytochemicals such as glycosides, tannins, alkaloids, flavonoids,
phlobatanin, anthraquinone and saponin were detected in the epicarp, mesocarp and seeds of the Cucurbits
under investigation.
Introduction: In Africa, we assessed the performance of all the three options of International Reference Ionosphere 2012, IRI-2012 (i.e. IRI-2001, IRI-2001COR and IRI-NeQuick), NeQuick-2 and IRI-Plas 2015 models prior to and during 2009 sudden stratospheric warming (SSW) event to predict equatorial ionization anomaly (EIA) crest locations and their magnitudes using total electron content (TEC) from experimental records of Global Positioning System (GPS). We confirmed that the IRI-Plas 2015 that appeared as the best compared to all of the models as regard prediction of the EIA crest locations in the northern hemisphere of Africa is due to discontinuities in the GPS data between ?8° N and 22° N. As regard the predictions of EIA crest magnitudes and the location of EIA crests in the southern hemisphere of Africa, they are not present in all the models. The NeQuick-2 model does not have the capability to predict either the EIA crest location in the northern or southern hemisphere. The SSW effect on the low latitude was able to modify a single EIA crest to pre-noon and post noon EIA crests in the northern hemisphere during the SSW peak phase and significantly reduced the GPS TEC magnitudes over the hemispheres as well. These SSW effects and delays of plasma transportation to higher latitudes in GPS TEC were absent in all the models. For future improvements of IRI-2012, NeQuick-2 and IRI-Plas 2015 models, SSW conditions should be included in order to characterize the effect of lower atmosphere on the ionosphere. The EIA trough modeling is only present in IRI-2001COR and IRI-2001NeQuick options. In the middle latitude, all the model could not predict the location of highest TEC magnitudes found at RBAY (Richardsbay, South Africa).
Introduction: This paper presents dynamic model of COVID-19 and citizens reaction from a fraction of the population in Nigeria using fractional derivative. We consider the reported cases from February to June 2020 using fractional derivative. The Stability analysis of the model was carried out and the basic reproduction number was calculated via the next generation matrix. The fractional derivative model was solved numerically and many graphs presented accordingly which could serve as a yard-stick of reducing this menacing virus and policy making.
Introduction: This paper presents dynamic model of COVID-19 and citizens reaction from a fraction of the population in Nigeria using fractional derivative. We consider the reported cases from February to June 2020 using fractional derivative. The Stability analysis of the model was carried out and the basic reproduction number was calculated via the next generation matrix. The fractional derivative model was solved numerically and many graphs presented accordingly which could serve as a yard-stick of reducing this menacing virus and policy making.
Introduction: A popular orientation about the meaning of human life in scholarly and public discourses is to conceive of human life as a form of existence whose essential value exists per se, that is, human life is necessary and not contingent on other ideals or entities. The import of this orientation is that human life is valuable in and by itself; and thus held to be sacred. This article employs expository and hermeneutical approaches in arguing for a fluid and ambivalent understanding of human life among the Yorùbá people mostly in Nigeria. By drawing from orature – sayings, anecdotes, proverbs – the article shall argue for the preponderance among the Yorùbá of a situation approach where the quality of life of an individual, social status, moral conduct and the particular context of death determines the value attached to human life. Such
Introduction: Participatory expressions of spirituality have begun to flourish over the last few decades through the collaborative efforts and individual journeys of a network of scholars and practitioners. Several authors have made important contributions to the ongoing definition of participatory spirituality (including but not limited to Ferrer 2002, 2008, 2010, 2011; Ferrer et al. 2004; Ferrer and Sherman 2008; Heron 1996, 1998, 2006; Reason 1994b, 1998b; Reason and Bradbury 2001a; Sherman 2008; Tarnas 2001, 2002). By way of orienting the definition given here, I adopt a three-question format borrowed from an earlier definition (Reason 1998b) of participatory spirituality that includes the questions of methodology, epistemology, and ontology. The order in which these questions will be introduced is not arbitrary.
Introduction: Nikolai Jeffs received his BA and Ph. D in Literature from the University of Essex, UK. He currently lives in Slovenia where he teaches at the Faculty of Humanities, University of Primorska, and at the Faculty of Arts, University of Ljubljana. He has published in both English and in Slovene on a wide variety of subjects ranging from postcolonial literature and popular culture to activism and the new social movements. Among other things, he also co-edited the first Slovene volume dedicated to contemporary African studies (Afrike, together with Borut Brumen, 2000) and the first Slovene postcolonial studies reader (Zbornik postkolonialnih študij, 2007). He can be contacted at nikolaijeffs@ gmail. com.
Introduction: Many authors have noted that wisdom is making a comeback, after being associated for a long time with old people, tradition, and conservative caution in a culture of youth, modernization, innovation, and risky exploration. The revival of wisdom is especially evident in areas where knowledge and (technical) knowhow come up against questions of ethics, values, beauty, the shaping and flourishing of the whole person, the common good, and long-term perspectives. 1 As will become clear throughout this paper, the resurgence of wisdom can be explained as a reaction against the negative effects of the dominance of scientific rationality, which boasts of its objectivity and its independence from ethical and existential considerations. Many people ask themselves “how the modern world can retrieve a wisdom, ie a knowledge, a conscience that is not only based on objects of knowledge, but relies also on life itself as it is lived daily, on a way of living and existing?” 2 From a broader, historical and cross-cultural perspective, the unilateral focus on scientific rationality in the West is rather exceptional. Religious and secular traditions around the world, from Hinduism over the mythologies of ancient Egypt and Greece to those of Northern Europe, from Buddhism, Confucianism, and Taoism, over Zoroastrianism to Judaism and Christianity, abound with revelations of wisdom. These traditions have permeated the history of humankind with stories and legends about and sayings of wise men and women.
Introduction: La mission des chercheurs africains issus des milieux urbains pour développer le savoir dans les zones de l’Afrique rurale se confronte à deux défis significatifs: la prédominance des mythes et «l’être comme force» au sein du réseau africain de la gnose, et l’attitude méprisante des chercheurs issus des milieux urbains envers les systèmes de connaissances indigènes (IKS). Cette approche est le résultat d’efforts coloniaux pour sauvegarder l’hégémonie épistémique et le néocolonialisme par le biais d’un assujettissement des Africains qui va à l’encontre d’un éventuel système de connaissances africain. L’idée fixe qui porte sur les mythes et sur la force des acteurs issus du milieu rural, mais également sur celle du système de connaissances acadé¬ mique constitue, des deux côtés, des structures de pouvoir qui ont pour effet d’étouffer les tentatives accumulées pour comprendre l’Afrique de l’intérieur. Ce travail, en s’ orientant vers le savoir de la communauté Yoruba, applique une approche de reconstruction en proposant deux voies qui mènent à un développement solide de la base du savoir africain. La première voie discute le fait que les acteurs ruraux qui contribuent au développement du savoir africain doivent éclaircir la situation là où il est nécessaire de le faire. La seconde voie se penche sur l’urgence pour parvenir à une complète décolonisation. Alors que la première voie conçoit l’évolution du rural à partir des mythes et se dirige vers la formation d’un système épistémique libéral, la se-conde voie souhaite se débarrasser de l’incrédulité et du mépris des chercheurs urbains envers la réalité du savoir en Afrique
Introduction: Die Aufgabe der Fortentwicklung des Wissens über afrikanische ländliche Gebiete seitens der urbanen Forscher Afrikas stößt auf zwei bedeutende Herausforderungen: die Überlegenheit der Mythen und „das Wesen als Macht “im Netz ruraler afrikanischer Gnosis sowie die verächtliche Haltung urbaner afrikanischer Forscher gegenüber den indigenen Wissenssystemen (IKS). Ein solches Herangehen ist das Ergebnis kolonialer Bemühungen, die epistemische Hegemonie und Neokolonialisierung beizubehalten, und zwar mithilfe von Afrikanern, über die man gegen die Interessen des afrikanischen Wissenssystems die Oberhand behielt. Die Fixierung auf den Mythos und die Macht der ländlichen Akteure sowie des westlichen, akademisch orientierten Wissenssystems vereint beiderseitig antagonistische Machtstrukturen mit dem kumulativen Effekt, Versuche zu ersticken, Afrika von innen heraus zu verstehen. Diese Arbeit, indem sie sich auf das Wissen der Yoruba¬-Gesellschaft konzentriert, setzt den rekonstruktiven Ansatz ein und schlägt zwei Wege zur Entwicklung einer robusten afrikanischen Wissensbasis vor. Der erste Weg argumentiert, dass die ruralen Akteure, die der Entwicklung der afrikanischen Erkenntnis ihren Beitrag leisten, erforderlichenfalls entzaubert werden müssen. Der zweite Weg ist auf die Dringlichkeit der Umsetzung einer vollständigen Dekolonisation ausgerichtet
Introduction: Zadatak razvijanja znanja o afri?kim ruralnim podru?jima od strane urbanih afri?kih istraživa?a susre?e se s dva zna?ajna izazova: nadmo? mitova i ‘bi?e kao sila’u mreži ruralne afri?ke gnoze i prijezirno držanje urbanih afri?kih istraživa?a spram domoroda?kih sustava znanja (IKS). Ovaj je pristup rezultat kolonijalnih nastojanja da se sa?uva epistemi?ka hegemonija i neokolonijalizacija uz pomo? Afrikanaca koje se okrenulo protiv mogu?nosti afri?kog sustava znanja. Fiksacija na mit i silu ruralnih aktera i zapadnja?kog akademski orijentiranog sistema znanja sa?injava obostrano antagonisti?ke strukture mo?i s kumulativnim efektom zagušivanja pokušaja da se Afriku razumije iznutra prema van. Ovaj rad, usmjeravaju?i se na društveno znanje Yoruba, primjenjuje rekonstruktivni pristup predlažu?i dva puta do razvoja robusne afri?ke baze znanja. Prvi put argumentira da se ruralni akteri koji doprinose razvoju afri?ke spoznaje moraju raš?arati gdje je to potrebno. Drugi je put usmjeren na urgentnost postizanja potpune dekolonizacije. Dok prvi put vidi kretanje ruralnog od mitova prema artikulaciji liberalnog epistemi?kog sistema, drugi put želi ukloniti nevjericu i prijezir koji urbani istraživa?i imaju o zbilji znanja u Africi.
Introduction: The task of advancing knowledge on Africa from rural African spaces by urban African researchers confronts two formidable challenges; namely, the preponderance of myths and ‘being as a force’in the network of rural African gnosis and the contemptuous poise of the urban African researcher against indigenous knowledge systems (IKS). This attitude is the aftermath of colonial efforts at reserving epistemic hegemony and neocolonisation by Afri cans who have been inundated against the possibility of an African knowledge system. The fixation on myths and force by rural agents and western academyderived knowledge sys tem constitute mutually antagonistic power structures with the cumulative effect of stifling efforts at understanding Africa from inside out. This paper focusing on the Yoruba knowl edge society employs a reconstructive approach in proposing two paths to the development of a robust African knowledge base by African researchers. The first path argues that rural agents contributing to developing African episteme must disenchant where necessary. The second is directed at the urgency of achieving a consummated decolonisation.
Introduction: This paper is an addition to existing scholarly literature regarding the theme of gender depiction in media practice, particularly as it relates to the portrayal or stereotyping of the female sex and the undesirable effect of negative gender role identification by women. This paper argues for a re-negotiation of gender depiction in media practice through increased functioning of the active voices of women, who themselves are at the receiving end of skewed media practices. With the widening of the frontiers of gender discourse to include the active voices of women, this women’s agency approach to the challenge of negative media representation becomes appropriate in the quest for greater advancement of gender equity.
Introduction: The objective of the study was to evaluate the influence of brand image and promotional mix on consumer buying decision. Descriptive survey research design was adopted as the study guide. Judgemental and purposive sampling techniques were used in which four hundred (400) copies of the research instrument were administered to beverage consumers in Lagos State, Nigeria, out of which three hundred and eighty four (384) copies of the questionnaire were filled and returned. Pearson Product Moment correlation was used to analyse the data generated from the respondents. The findings revealed that brand image, advertising, sales promotion and personal selling have significant influence on consumer buying decision at. 01 level (2-tailed). The study concluded that the way a product is promoted coupled with the brand integrity of such product encourages consumers to purchase it and make repeat purchase of it, and as well enhances the referral of such product to other prospects. The study therefore recommended to the organizations, especially those that engage in the marketing of the fast-moving consumer goods, to focus on distinct promotional mix, as the study empirically proved that perception of brand image is capable of influencing consumer buying decision on sustainable basis. It is also recommended that each marketing company should adopt a combination of promotional mix that can bring about distinct outcomes in terms of turnover, improved market share, customer retention, profitability, and productivity among others.
Introduction: This paper investigates the impact leadership style on organizational climate in the Nigerian insurance industry. The empirical study was conducted via a multi-respondent survey of 15 insurance companies quoted on the floor of Nigerian stock exchange as at 31st December, 2013. Using the framework from Ojokuku., Odetayo and Sajuyigbe (2012), factors manifesting organizational climate were canonically correlated and regressed on the key factors manifesting leadership styles. While leadership style was measured using six dimensions (charismatic, transactional, transformational, autocratic, bureaucratic and democratic) proposed by Ojokuku., Odetayo and Sajuyigbe (2012), organizational climate was measured through a set of questionnaire that we developed based on the eight organizational climate dimension proposed by Litwin and stringer (1968). Findings based on the survey revealed that leadership style positively affected organizational climate in the Nigerian insurance industry. Specifically, our results suggest that apart from autocratic and bureaucratic leadership styles; transactional leadership style, democratic leadership style, charismatic leadership style, and transformational leadership style are the key leadership styles that influenced organizational climate in the Nigerian insurance industry. The model provides predictive implications on improved organizational climate, given the activities of critical variables manifesting successful leadership styles.
Introduction: The objective of the study is to determine the extent to which multinational firms have spurred up economic development in Nigeria. Multinational Corporations (MNCs) are those having operations in more than one country. They are subjects to changes in international exchange rates, tariffs, duties, and restrictions on trade. The most successful ones have established production points where labour is cheap, and secures affordable transportation to deliver to their markets. The study used scholarly journals, articles, and textbooks to review the activities of multinational firms in relation to Nigeria’s economic development, in relation to growth and development, technology transfers and policy issues. From the exploratory literature, the study discovered that multinational corporations have contributed to the economic development of Nigeria, though varies, the extent of technology internalization and transfers still remains a mirage, while some of the MNCs still engage in unethical business practices that soils their image and the image of Nigeria. Specifically, the gap in technology intensities from MNCs in Nigeria seemed to be widening despite the recent comparative improvement in FDI inflows into the country. Consequently, there is urgent need to upgrade learning and capabilities of the local firms in the country, through the formulation of strategic FDI and technology transfer policies to safeguard the possible negative impact of the declining FDI inflow from MNCs. However, to further attract foreign investors, Nigeria should strengthen and broaden policies to facilitate cost effectiveness by reducing tariffs on imported inputs, as well as, improvement in …
Introduction: The objective of the study was to investigate the influence of leadership style on employees’ performance in selected private universities in Ogun State, Nigeria. Descriptive survey research design was adopted as the study guide. Multi stage sampling technique was used for this study due to the varied characteristics of the institutions. Five hundred (500) copies of questionnaire were administered to academic and non-academic staff in the selected private universities out of which four hundred and thirty five (435) copies were filled and returned. Pearson Product Moment correlation was used to analyse the data gathered from the respondents. The study revealed that only transactional leadership style have no significant influence on employees’ performance while charismatic and transformational leadership styles has positive and significant influences on employees’ performance in selected private universities in Ogun State, Nigeria. The validation of charismatic and transformational leadership styles, by our model, as the key leadership styles that influenced employees’ performance in our study, therefore provides predictive implications on improved employees’ performance, given the activities of these leadership styles.
Introduction: Telecommunication Service Delivery and Customer Satisfaction: A Study of Telecom Subscribers in Ogun State, Nigeria
Introduction: Confict Management Strategies: A Tool for Industrial Harmony
Introduction: In this present world, a modern telecommunication infrastructural development is not only essential for domestic economic growth, but also a prerequisite for participation in the increasingly competitive world market and for attracting new investments. The main objective of the study is to examine the effect of promotional mix (advertising, sales promotion, public relations, personal selling, and direct marketing) on customer patronage among telecom subscribers in Lagos and Ogun States, Nigeria. Survey research design was used for the study. Data was collected through the use of questionnaire. Descriptive statistics was used to analyze the respondents’ biodata while multiple regression analysis was used to test the hypothesis formulated. Findings of the study revealed that advertising, sales promotion, public relations, personal selling, and direct marketing had significant effect on customers’ choice of mobile telecommunication network in Lagos and Ogun States, Nigeria. Advertising, sales promotion, public relations, personal selling, and direct marketing had significant effect on customers’ expense among telecom subscribers in Lagos and Ogun State. The study concluded that customer patronage will increase in mobile telecommunication firms when they provide adequate information about the services they offer through sufficient advertisements, publicity, personal selling, and direct marketing as well as provide the needed incentives that will encourage rapid purchase of their offers. The study recommended that telecommunication service providers should put in more efforts in their advertisement campaigns, carry out frequent sales promotion …
Introduction: Crawford Journal of Business and Social Sciences
Introduction: International Journal of Management Science and Entrepreneurship
Introduction: International Journal of Management Science and Entrepreneurship
Introduction: L’argument majeur de ce travail se construit sur l’importance de diminuer l’utilisation des catégories occidentales de la morale telles qu’on les trouve dans le concept du soi et du personnalisme lorsque l’accent est mis sur les problèmes moraux et pratiques dans certaines contrées africaines ; spécialement chez les Igbos et les Yorubas appartenant aux communautés nigériennes. En résumé, le personnalisme en tant que théorie éthique promeut la valeur et la dignité de l’être humain, rendant cette théorie de la morale attractive et facilement applicable à un niveau général du problème de la morale. Cependant, cela s’accompagne de quelques risques puisque la connaissance des problèmes moraux n’est pas conçue de la même manière au sein des diverses sociétés et cultures. Par exemple, la conception africaine de la personne humaine, à savoir la manière dont elle est représentée dans le système de la morale des peuples Yoruba et Igbo, ne possède pas de différenciation catégorique stricte entre le transcendant, l’esprit et le matériel, à l’instar des conceptions occidentales qui mettent l’accent sur la dimension matérielle, fonctionnelle et corporelle. Il reste à voir si un débat de ce type a une importance instrumentale dans la production des valeurs et d’un cadre nécessaire pour étudier les innombrables problèmes avec lesquels le continent africain est confronté.
Introduction: Temeljni argument ovog rada izgra?en je na osnovi važnosti ublažavanja korištenja zapadnih kategorija morala kako ih se može na?i u konceptu sebstva i personalizma pri apostrofiranju moralnih i prakti?nih problema u nekim dijelovima Afrike; specifi?no u etni?kim nigerijskim skupinama Igboa i Yorube. Sažeto, personalizam kao eti?ka teorija promi?e vrijednost i dostojanstvo ljudskog bi?a, što je ?ini atraktivnom teorijom morala koja se lako primjenjuje na op?em planu problema morala. Me?utim, s tim dolaze neke opasnosti jer je znanje o nekim moralnim problemima druga?ije pojmljeno od razli?itih društava i kultura. Primjerice, afri?ka koncepcija ljudske osobe, kako je predstavljena u moralnom sistemu Yoruba i Igbo naroda, nema oštro kategori?ko razlikovanje izme?u transcendentnog, duhovnog i materijalnog, kako je to slu?aj u koncepcijama Zapada koje naglašavaju materijalnu, funkcionalnu i tjelesnu dimenziju. Predstoji vidjeti da rasprava ovog tipa ima instrumentalnu važnost u pribavljanju vrijednosti i potrebnog okvira za ispitivanje bezbroj problema s kojima se susre?e afri?ki kontinent.
Introduction: Das zugrundeliegende Argument dieser Arbeit baut auf der Wichtigkeit der Minderung der Verwendung von westlichen Moralkategorien auf, wie man sie im Konzept des Selbst und des Personalismus bei der Apostrophierung moralischer und praktischer Probleme in einigen Teilen Afrikas, kennzeichnend in ethnischen nigerianischen Gruppen von Igbo und Yoruba, antreffen kann. Kurzum, der Personalismus als ethische Theorie fördert den Wert und die Würde des menschlichen Wesens, was ihn zu einer attraktiven Moraltheorie macht, die leicht auf das allgemeine Gefilde des Moralproblems angewandt werden kann. Damit gehen allerdings etliche Gefahren einher, da das Wissen über einige moralische Probleme in diversen Gesellschaften und Kulturen unterschiedlich ausgedeutet wird. Beispielshalber verfügt die afrikanische Konzeption der menschlichen Person, wie sie im Moralsystem der Völker Yoruba und Igbo präsentiert wird, über keine scharfe kategorische Differenzierung zwischen Transzendentem, Geistigem und Materiellem, wie das in den Konzeptionen des Westens der Fall ist, die materielle, funktionale und körperliche Dimension hervorheben. Es bleibt zu sehen, dass die Diskussion dieses Typs von instrumentaler Wichtigkeit ist bei der Wertebeschaffung und beim notwendigen Rahmen zur Untersuchung unzähliger Probleme, mit denen der afrikanische Kontinent konfrontiert ist.
Introduction: The idea of the university is essentially a philosophical idea. This is owing to the fact that separating young people from the core of society, with the view to giving them intellectual training under special settings called the university shows some epistemic justification in the possibility of the transformation of individual for the good of society. This firm belief in the possibility of the transformation of the individual cannot be limited to training and acquisition of skills, it has to, basically be centered on the development of the intellect for effective living within society. In the Nigerian experience, there is a heavy acceptance of a corrosive idea of the university in terms of seeing the university as a place for acquisition of skills and skills alone, at least if what we see in the job market is anything to go by. There is a general misunderstanding about the true purpose of the university to the extent that the idea itself becomes fuzzy in our understanding and also forms a large part of the reasons given for the formation of the private universities in Nigeria. This paper therefore using critical analysis and secondary sources is submitting that if the present crop of private universities in Nigeria is to help effectively in the transformation of society, there should be an unfuzzying process done to our understanding of the idea of the university. There should be an understanding that education as different from schooling, is an idea that is capable of developing the intellectual faculties of a person first before giving the person requisite skills. When this is taken into consideration, we would have recovered the authentic idea of the university in Nigeria.
Introduction: FALSAFA, Journal of Philosophy
Introduction: The fundamental argument of this paper is built around the importance of deemphasising the use of Western moral categories as found in personhood and personalism in addressing moral and practical issues in some parts of Africa; specifically, among the Igbo and Yoruba ethnic groups of Nigeria. Essentially, personalism as an ethical theory promotes the value and dignity of human beings which makes it an attractive moral theory that is likely to be applied universally to moral issues. However, there are some dangers in the universal applicability of the theory, as knowledge of certain moral issues is perceived by different societies and cultures. As an instance, the African conception of the human person as repre sented in the Igbo and Yoruba moral systems has no strict categorical difference between the transcendental, spiritual and the material, as it is in the Western conception, which emphasises the material, the functional and the physical dimensions. It is, therefore, to be seen that a discourse of this sort is pertinent and instrumental in providing the values and needed framework to interrogate the myriad of problems faced in the African continent.
Introduction: One of the problems bedeviling development and growth of most African nation is the problem of corruption. Nigeria as a nation has not been spared of this. This explains why she has been described as a failing state, from the political, economic, social and moral perspectives. The Nigerian nation has been experiencing unprecedented levels of deeprooted crises. Much of the crisis include: political corruption, poverty, social and religious upheavals, ethnic conflicts, unemployment, endemic diseases, disrespect for the rule of law, flagrant disrespect for human freedom, equality and human rights. These issues have earned the nation appellations like,'failed state','rogue or the pre-bendal state.'Despite the efforts of government agencies and other relevant organizations, the problems of corruption remain unresolved. In view of the foregoing, this paper submits that, the Catholic Church as a stakeholder in the struggle against corruption must explore new mechanisms and improve the old ones, which include: repackaged education, enlightenment campaigns, seminars, symposia and conferences, and so to combat the problem of corruption in Nigeria.
Introduction: Abstract
Fresh whole plant of Heliotropium indicum was collected, air dried, pulverized and successively extracted with
n-hexane, ethyl acetate and ethanol to obtain n-hexane, ethyl acetate and ethanol extracts respectively. The
phytochemical screening of the extracts revealed the presence of glycosides, cardiac glycosides, tannins,
terpenoids and polyphenols in all the three extracts. Alkaloids, saponins, flavonoids and steroids were present in
ethyl acetate and ethanol extracts. The antimicrobial sensitivity tests of the crude extracts on three gram positive
bacteria, five gram negative bacteria and five fungi showed significant inhibition zones against most of the
tested organisms. The isolated compound from the ethyl acetate extract was characterized with Fourier
Transform Infrared Spectroscopy and Gas Chromatography-Mass Spectroscopy (GC-MS) analysis and data
matching with standard in literature.
Introduction: The OpenFOAM computational fluid dynamics code was used to investigate the performance of three combustion models, namely, Muppala, Zimont and Algebraic. The performance characteristics of these models were tested in a fully premixed (stoichiometric (?=1.0)) modern, high-performance 4-valve, iso-octane, dual overhead cam (DOHC) engine with quasi-symmetric pent roof combustion chamber running at 1500 revolutions per minute. The performance characteristics of the three combustion models were found to be reasonably representative of measurement data that are usually observed in internal combustion engine test bed experiments. The combined or overall duration ??o, of the flame development ??d and propagation period ??b? for the three models were 5.53 ms, 5.69 ms and 6.04 ms for the Muppala, Zimont and Algebraic models, respectively, and these values correspond to 49.75?CA, 51.175 CA and 54.425 CAwhich are well within the 30???o?90 acceptable degree crank angle range during typical internal combustion engine operations. The maximum pressure with the corresponding degree crank angle positions at which they occur for the Muppala, Zimont and Algebraic models were found to be: (59.86bar,6.83?CA), (53.19bar,11.9?CA) and (47.64bar,12.1?CA) respectively. Furthermore, the results from the present study show that the flame-development period ??d, was almost identical for the three combustion models, whereas the rapid-burning interval ??b, was almost indistinguishable for the three combustion models up to about the 80% mark of the regress variable. In specific terms, the complete salient findings from this study are summarised in the conclusion section of this study.
Introduction: Abstract
Both the conventional (classic) and advanced exergetic analytical methods were used to investigate the improvement potentials of a pulverised coal-fired 750 MW supercritical steam power plant. The results show that the subsystem that contributed the most to exergy destruction is the condenser (CND) at about 1.25% and closely followed by the boiler at 1.23%. Furthermore, the data obtained from the present study show that the dominant contributor to the overall exergy destruction in each of the subsystems was the endogenous part of exergy destruction, E ?_(D,k)^(E,N). In addition, the results show that steam turbines, especially TB1, TB4, TB5, TB6, TB7 to TB17, the condenser and the boiler would benefit immensely by improving their avoidable endogenous exergy destructions E ?_(D,k)^(AV,EN). This investigation also shows that the overall unavoidable exergy destruction within the entire power plant was about 42.8%, while the potential for improving the entire power plant was approximately 2.5%. Other important results from this study are comprehensibly documented in the conclusion section.
Introduction: The OpenFOAM computational fluid dynamics code was used to investigate the performance of three combustion models, namely, Muppala, Zimont and Algebraic. The performance characteristics of these models were tested in a fully premixed (stoichiometric (?=1.0) modern, high-performance 4-valve, iso-octane, dual overhead cam (DOHC) engine with quasi-symmetric pent roof combustion chamber running at 1500 revolutions per minute. The performance characteristics of the three combustion models were found to be reasonably representative of measurement data that are usually observed in internal combustion engine test bed experiments. The combined or overall duration ??_o, of the flame development ??_d, and propagation period ??_(b^' ), for the three models were 5.53 ms, 5.69 ms and 6.04 ms for the Muppala, Zimont and Algebraic models, respectively, and these values correspond to 49.75 °CA, 51.175°CA and 54.425 °CA which are well within the 30? ??_o?90 acceptable degree crank angle range during typical internal combustion engine operations. The maximum pressure with the corresponding degree crank angle positions at which they occur for the Muppala, Zimont and Algebraic models were found to be: (59.86 bar, 6.83°CA), (53.19 bar, 11.9 °CA) and (47.64 bar,12.1°CA) respectively. Furthermore, the results from the present study show that the flame-development period ??_d, was almost identical for the three combustion models, whereas the rapid-burning interval ??_(b^' ) was almost indistinguishable for the three combustion models up to about the 80% mark of the regress variable. In specific terms, the complete salient findings from this study are summarised in the conclusion section of this study.
Introduction: Abstract
Both the conventional (classic) and advanced exergetic analytical methods were used to investigate the improvement potentials of a pulverised coal-fired 750 MW supercritical steam power plant. The results show that the subsystem that contributed the most to exergy destruction is the condenser (CND) at about 1.25% and closely followed by the boiler at 1.23%. Furthermore, the data obtained from the present study show that the dominant contributor to the overall exergy destruction in each of the subsystems was the endogenous part of exergy destruction, E ?_(D,k)^(E,N). In addition, the results show that steam turbines, especially TB1, TB4, TB5, TB6, TB7 to TB17, the condenser and the boiler would benefit immensely by improving their avoidable endogenous exergy destructions E ?_(D,k)^(AV,EN). This investigation also shows that the overall unavoidable exergy destruction within the entire power plant was about 42.8%, while the potential for improving the entire power plant was approximately 2.5%. Other important results from this study are comprehensibly documented in the conclusion section.
Introduction: Abstract
A spark ignition engine two-zone simulation code was used to conduct a systematic study of the effects of combustion chamber wall temperature, start of heat release/ignition timing, fuel–air equivalence ratio, engine speed, indicated mean effective pressure and exhaust gas recirculation on an individual basis on NO_X emissions in a 5.734-liter, V8 spark ignition engine. The two-zone model which incorporates heat transfer, blow-by and other losses was used. In this model, the flame traverses the charge resulting in burned and unburned zones. The unburned zone contains the reactants (fuel and air), and there is no reaction between the constituents. The burned zone consists of the products of combustion and dissociation. The formation of nitric oxide was obtained using the extended Zeldovich nitric oxide reaction mechanism. The simulation program computes both equilibrium thermodynamics and rate-limited values of the concentration of oxides of nitrogen (NO_X) in parts per million (ppm) as a function of crank angle as well as its concentration in the exhaust gas stream. The study shows that the equilibrium NO is formed immediately after the start of combustion, and because of its strong dependence on temperature it rises rapidly to a maximum value of 8454.75 ppm, and declines rapidly as the pressure and temperature fall during expansion stroke to a final NO_X concentration value of 28.7 ppm. The results also show that spark retard and exhaust gas recirculation are effective strategies for NO_X emission control. The complete results from this study are summarized in the conclusion.
Introduction: Abstract
A spark ignition engine two-zone simulation code was used to conduct a systematic study of the effects of combustion chamber wall temperature, start of heat release/ignition timing, fuel–air equivalence ratio, engine speed, indicated mean effective pressure and exhaust gas recirculation on an individual basis on NO_X emissions in a 5.734-liter, V8 spark ignition engine. The two-zone model which incorporates heat transfer, blow-by and other losses was used. In this model, the flame traverses the charge resulting in burned and unburned zones. The unburned zone contains the reactants (fuel and air), and there is no reaction between the constituents. The burned zone consists of the products of combustion and dissociation. The formation of nitric oxide was obtained using the extended Zeldovich nitric oxide reaction mechanism. The simulation program computes both equilibrium thermodynamics and rate-limited values of the concentration of oxides of nitrogen (NO_X) in parts per million (ppm) as a function of crank angle as well as its concentration in the exhaust gas stream. The study shows that the equilibrium NO is formed immediately after the start of combustion, and because of its strong dependence on temperature it rises rapidly to a maximum value of 8454.75 ppm, and declines rapidly as the pressure and temperature fall during expansion stroke to a final NO_X concentration value of 28.7 ppm. The results also show that spark retard and exhaust gas recirculation are effective strategies for NO_X emission control. The complete results from this study are summarized in the conclusion.
Introduction: Abstract
A validated spark ignition engine combustion model was used to investigate the operational feasibility of subjecting a 5.734 L, V8 engine to the Honda variable (valve) timing and electronic lift control (VTEC) management strategy. The numerical results were found to be in good agreement with measured data during the compression and expansion strokes. However, the results of the numerical model overestimated the measured data by approximately 10% -15% during the combustion phase. The reason for this discrepancy could be due to the fact that the turbulence levels within the combustion chamber during the experiment was not specified. Therefore, we accounted for turbulence in the simulation with a flame speed multiplying factor, f_t=7.0. The investigations cover operations at low, mid-range and full power periods; for fuel-air equivalence ratios, ? of 0.67, 1.10 and 1.18. The results of the study show that operational viability of a 5.734 L, V8 engine when subjected to the VTEC engine management scheme was achievable, provided high levels of turbulence were maintained, especially for extra lean mixtures, that is, for fuel-air equivalence ratio, ?=0.67. This work shows that the values of the flame speed factor, ftft have to be carefully selected in order to achieve complete combustion.
Introduction: Abstract
A computational study was used to investigate the effects of temperature and pressure on the extended Zeldovich mechanism. Two temperatures, namely 2,600 and 1,900 K, were used while keeping the species concentration of all component products constant at 1.0 mole/m3. These temperatures were selected because they represent typical operating conditions for internal combustion engines. Pressure was varied by decreasing the species concentration for all component species by 10% while keeping the temperatures constant. The pressures were 1.513 x 105 and 1.362 x 105 N/m2 for T=2,600 K and 1.106 x 105 and 9.95 x 104 N/m2 for T=1,900 K, 1.513 x 105 and 1.362 x 105 N/m2 for T=2,600 K and 1.106 x 105 and 9.95 x 104 N/m2 for T=1,900 K. The estimate of the uncertainties in the global errors of [NO], [N], and [O] for the conditions investigated was found to vary between (±4.10 and ±4.34%), (±9.33 and ±10.1%), and (±5.73 and ±9.07%), (±4.10 and ±4.34%), (±9.33 and ±10.1%), and (±5.73 and ±9.07%), respectively. The numerical results show that high temperatures result in faster rate of production of both [NO] and [O] and faster rate of [N] depletion. At moderately low temperatures (?1,900 K), the rate of depletion of both oxygen and nitrogen atoms is very high. It was observed that changes in pressure had a minor or at best marginal influence on the production of [NO], [N], and [O]. The work also shows that for all the equilibrium points investigated, only one in each case was physical and the others were non-physically realizable because at least one of their equilibrium points was negative.
Introduction: Abstract
A computational study was used to investigate the effects of temperature and pressure on the extended Zeldovich mechanism. Two temperatures, namely 2,600 and 1,900 K, were used while keeping the species concentration of all component products constant at 1.0 mole/m3. These temperatures were selected because they represent typical operating conditions for internal combustion engines. Pressure was varied by decreasing the species concentration for all component species by 10% while keeping the temperatures constant. The pressures were 1.513 x 105 and 1.362 x 105 N/m2 for T=2,600 K and 1.106 x 105 and 9.95 x 104 N/m2 for T=1,900 K, 1.513 x 105 and 1.362 x 105 N/m2 for T=2,600 K and 1.106 x 105 and 9.95 x 104 N/m2 for T=1,900 K. The estimate of the uncertainties in the global errors of [NO], [N], and [O] for the conditions investigated was found to vary between (±4.10 and ±4.34%), (±9.33 and ±10.1%), and (±5.73 and ±9.07%), (±4.10 and ±4.34%), (±9.33 and ±10.1%), and (±5.73 and ±9.07%), respectively. The numerical results show that high temperatures result in faster rate of production of both [NO] and [O] and faster rate of [N] depletion. At moderately low temperatures (?1,900 K), the rate of depletion of both oxygen and nitrogen atoms is very high. It was observed that changes in pressure had a minor or at best marginal influence on the production of [NO], [N], and [O]. The work also shows that for all the equilibrium points investigated, only one in each case was physical and the others were non-physically realizable because at least one of their equilibrium points was negative.
Introduction: Abstract
An experimental study based on Laser Doppler Velocimetry (LDV) measurements was used to investigate the effects of piston geometries and intake swirl levels on the structure of flow quantities at the top dead center (TDC) position of a simulated internal combustion engine (ICE). Rapid intake and compression machine (RICM) was used for this study. The two combustion chamber types investigated were the bowl-in-piston and the re-entrant bowl geometries. The experimental results show that turbulence is produced around the TDC position in the high-shear regions formed near the piston bowl rim. These high-shear regions were established by the interaction of squish and swirl. The results also show that the intake-generated turbulence has significantly decreased such that its influence on turbulence at TDC was negligible. In general, it was observed that turbulence around TDC was more intense in the re-entrant bowl under all swirl conditions than in the bowl-in-piston combustion chamber. The results of the data from this study show that the random uncertainties in the mean radial and tangential velocities for both chamber configurations ranges from ±13.2% to ±19.2%, while the uncertainties in the root mean square velocities were about ±14.1%.
Introduction: Abstract
An experimental study based on Laser Doppler Velocimetry (LDV) measurements was used to investigate the effects of piston geometries and intake swirl levels on the structure of flow quantities at the top dead center (TDC) position of a simulated internal combustion engine (ICE). Rapid intake and compression machine (RICM) was used for this study. The two combustion chamber types investigated were the bowl-in-piston and the re-entrant bowl geometries. The experimental results show that turbulence is produced around the TDC position in the high-shear regions formed near the piston bowl rim. These high-shear regions were established by the interaction of squish and swirl. The results also show that the intake-generated turbulence has significantly decreased such that its influence on turbulence at TDC was negligible. In general, it was observed that turbulence around TDC was more intense in the re-entrant bowl under all swirl conditions than in the bowl-in-piston combustion chamber. The results of the data from this study show that the random uncertainties in the mean radial and tangential velocities for both chamber configurations ranges from ±13.2% to ±19.2%, while the uncertainties in the root mean square velocities were about ±14.1%.
Introduction: Abstract
Numerical simulation studies were used to investigate the effects of piston geometries and intake swirl levels on the structure and evolution of the flow field at the top dead center (TDC) position of a simulated internal combustion engine (ICE). The piston shapes investigated were disc-shaped chamber, bowl-in-piston, and the re-entrant bowl geometries. The conditions considered are similar to those of production engines. The work focused on the near-wall and bowl entrance regions of the axisymmetric combustion chambers where strong swirl–squish interactions take place. The numerical calculations were performed with KIVA-II code. The k?? turbulence model was used in the present study. The results of this study show that high-shear regions and the consequent turbulence production occurred near the bowl entrance around the TDC of compression. Furthermore, this study shows that the re-entrant bowl piston configuration generated more turbulence quantities than both the disc-shaped and bowl-in-piston combustion chambers
Introduction: Abstract
A spark-ignition engine simulation code was used to study the effects of varying the following engine operating parameters—compression ratio, fuel–air equivalence ratio, residual mass fraction, and start of heat release/ignition timing on an individual basis on the performance of a 5.734 L, V-8 spark-ignition engine. The two-zone model was used where the same traverses the charge resulting in burned and unburned zones. The unburned zone contains the reactants (fuel and air), and there is no reaction between the constituents. The burned zone consists of the products of combustion and dissociation. The results of the present work show that maximum pressure and temperature occur at fuel–air equivalence ratio, ? of 1.01. Furthermore, the study shows that retarding or advancing the ignition timing from maximum brake torque causes a reduction in the power output of the cycle (indicated mean effective pressure) and hence in the cycle thermal efficiency as well. In general, it was observed that the computed results under estimated the measured values of the indicated mean effective pressures as follows: at 0.7? ??1.0, the computed results were between 5 and 6.86% lower than the measured engine data even though the qualitative trend was in excellent agreement with it, whereas the values of the measured indicated mean effective pressure were about 6.86–16.51% higher than the simulated results for fuel–air equivalence ratio in the range 1.0 ? ??1.4. The data reported indicate that in the range 0.7? ??1.0 the indicated thermal efficiency, ?, increases, whereas the indicated thermal efficiency has an approximate inverse relationship with the fuel–air equivalence ratio, ?, that is, ? ~ 1?? in the range 1.0 ? ??1.4. The other results from this study are summarized in the conclusion.
Introduction: Abstract
A spark-ignition engine simulation code was used to study the effects of varying the following engine operating parameters—compression ratio, fuel–air equivalence ratio, residual mass fraction, and start of heat release/ignition timing on an individual basis on the performance of a 5.734 L, V-8 spark-ignition engine. The two-zone model was used where the same traverses the charge resulting in burned and unburned zones. The unburned zone contains the reactants (fuel and air), and there is no reaction between the constituents. The burned zone consists of the products of combustion and dissociation. The results of the present work show that maximum pressure and temperature occur at fuel–air equivalence ratio, ? of 1.01. Furthermore, the study shows that retarding or advancing the ignition timing from maximum brake torque causes a reduction in the power output of the cycle (indicated mean effective pressure) and hence in the cycle thermal efficiency as well. In general, it was observed that the computed results under estimated the measured values of the indicated mean effective pressures as follows: at 0.7? ??1.0, the computed results were between 5 and 6.86% lower than the measured engine data even though the qualitative trend was in excellent agreement with it, whereas the values of the measured indicated mean effective pressure were about 6.86–16.51% higher than the simulated results for fuel–air equivalence ratio in the range 1.0 ? ??1.4. The data reported indicate that in the range 0.7? ??1.0 the indicated thermal efficiency, ?, increases, whereas the indicated thermal efficiency has an approximate inverse relationship with the fuel–air equivalence ratio, ?, that is, ? ~ 1?? in the range 1.0 ? ??1.4. The other results from this study are summarized in the conclusion.
Introduction: Abstract
The theory of thermoeconomics and local optimization were used to investigate how the cost of the resources consumed by a 450 MW power plant varies with the unit cost of the resources consumed, the technical production coefficients of the productive structure and/or the external demand for the products. In order to accomplish this, the costs of exergy of the productive structure were analyzed under three different conditions by using the relevant characteristic equations. In general, it was found that the thermoeconomic cost of a flow consists of two parts, namely the monetary cost of the fuel exergy (natural gas in the present study) needed to produce the flow, that is, its thermoeconomic cost and the costs due to the productive process (cost of capital equipment, maintenance, etc.). The results show that the steam leaving the boiler has the lowest exergy cost, while the condenser has the highest. The sequential quadratic programming (SQP) algorithm was used to obtain the optimized solutions of each major component of the plant. It was found that substantial operational and capital cost benefits were realized by optimizing most of the major plant equipment (boiler, turbines, feedwater heaters and the pumps). However, optimization of the condenser did not yield any cost benefit in capital equipment cost, but did produce some savings in operational cost.
Introduction: Abstract
The theory of thermoeconomics and local optimization were used to investigate how the cost of the resources consumed by a 450 MW power plant varies with the unit cost of the resources consumed, the technical production coefficients of the productive structure and/or the external demand for the products. In order to accomplish this, the costs of exergy of the productive structure were analyzed under three different conditions by using the relevant characteristic equations. In general, it was found that the thermoeconomic cost of a flow consists of two parts, namely the monetary cost of the fuel exergy (natural gas in the present study) needed to produce the flow, that is, its thermoeconomic cost and the costs due to the productive process (cost of capital equipment, maintenance, etc.). The results show that the steam leaving the boiler has the lowest exergy cost, while the condenser has the highest. The sequential quadratic programming (SQP) algorithm was used to obtain the optimized solutions of each major component of the plant. It was found that substantial operational and capital cost benefits were realized by optimizing most of the major plant equipment (boiler, turbines, feedwater heaters and the pumps). However, optimization of the condenser did not yield any cost benefit in capital equipment cost, but did produce some savings in operational cost.
Introduction: Abstract
An exergetic analysis of the main subsystems of a steam power plant was undertaken. The product of the entropy generation rate and the effective temperature (modified Gouy–Stodola law) was used to calculate the real power/exergy loss due to various irreversibilities present in the subsystems. The use of the effective temperature was deemed appropriate because its derivation depends on the dynamics of the subsystem(s) under consideration. The results of our analysis showed that the highest rate of entropy generation occurred in the condenser while the maximum rate of entropy generation for the feed-water heaters was observed in the Heater6. The reasons for these observations were discussed in the relevant sections of this study. The greatest power/exergy loss was observed in double-flow low-pressure turbine. This could be due to the fact that the inlet steam was split and flows axially in opposite directions through the turbine blades, thereby creating a lot of irreversibilities. According to the results of this study, it can be concluded that the most irreversible unit in the system is the condenser with 149 MW loss and followed by the high-pressure turbine with a power/exergy loss of 22.5 MW. It was observed that when environmental temperature was used in the calculation of power/exergy loss, the results always underestimated the real power/exergy loss. Finally, the results of this study have highlighted the areas where the various subsystems of the power plant can be improved. The analyses show where the largest quantities of power/exergy loss are being dissipated within the plant, thus pointing to areas where improvement in energy usage can be made. The use of exergy as a potential design and retrofit tool was also pointed out.
Introduction: Abstract
An exergetic analysis of the main subsystems of a steam power plant was undertaken. The product of the entropy generation rate and the effective temperature (modified Gouy–Stodola law) was used to calculate the real power/exergy loss due to various irreversibilities present in the subsystems. The use of the effective temperature was deemed appropriate because its derivation depends on the dynamics of the subsystem(s) under consideration. The results of our analysis showed that the highest rate of entropy generation occurred in the condenser while the maximum rate of entropy generation for the feed-water heaters was observed in the Heater6. The reasons for these observations were discussed in the relevant sections of this study. The greatest power/exergy loss was observed in double-flow low-pressure turbine. This could be due to the fact that the inlet steam was split and flows axially in opposite directions through the turbine blades, thereby creating a lot of irreversibilities. According to the results of this study, it can be concluded that the most irreversible unit in the system is the condenser with 149 MW loss and followed by the high-pressure turbine with a power/exergy loss of 22.5 MW. It was observed that when environmental temperature was used in the calculation of power/exergy loss, the results always underestimated the real power/exergy loss. Finally, the results of this study have highlighted the areas where the various subsystems of the power plant can be improved. The analyses show where the largest quantities of power/exergy loss are being dissipated within the plant, thus pointing to areas where improvement in energy usage can be made. The use of exergy as a potential design and retrofit tool was also pointed out.
Introduction: Abstract
A combined study based on laser Doppler velocimetry measurements and numerical simulation was undertaken in order to validate the KIVA II numerical code. A rapid intake and compression machine was used for the experimental studies, while the numerical calculations were performed with the KIVA II computational fluid dynamics code. The k-? turbulence model was used to represent the effects of turbulence. The measured mean radial and tangential velocities were found to be generally higher than their computed counterparts. The differences between these velocities range from 3.5% to 7% in magnitude for the re-entrant bowl chamber while they vary from 5% to 11% for the bowl-in-piston combustion chamber configuration. The measured values of the turbulence intensity close to the bowl axis in the re-entrant bowl chamber configuration were fairly accurately predicted, but the quality of the prediction diminishes as the bowl entrance region was approached. The values of the turbulence intensity were however, poorly reproduced near the axis of the bowl-in-piston chamber assembly. The experimental and predicted values of turbulence were found to differ by between 7% to 20% (re-entrant chamber) and 13% to 20% (bowl-in-piston). The results of the experimental data that were obtained from this study show that the random uncertainties in the mean radial and tangential velocities for both chamber configurations range from ±13.2% to ±19.2%, while the uncertainties in the root mean square velocities were about ±14.1%.
Introduction: Abstract. The main objective of this work is to present a brief tutorial
on minimal surfaces. Furthermore, a great deal of effort was made to
make this presentation as elementary and as self-contained as possible.
It is hoped that the materials presented in this work will give some motivations for beginners to go further in the study of the exciting field of
minimal surfaces in three dimensional Euclidean space and in other ambient spaces. The insight into some physical systems have been greatly
improved by modeling them with surfaces that locally minimize area. Such
systems include soap films, black holes, compound polymers, protein folding, crystals, etc. The relevant mathematical field started in the 1740s but
has recently become an area of intensive research. This is due to the wide
spread availability of powerful and relatively inexpensive computers combined with the preponderance of suitable graphical application software
packages. Furthermore, its anticipated use in the medical, industrial and
scientific applications have provided further impetus for research efforts
concerning minimal surfaces. It was shown that minimal surfaces do not
always minimize area. Some advantages and shortcomings of the Weierstrass equations were highlighted. Finally, the proofs of Bernstein’s and
Osserman’s theorems were sketched out and some other improved (sharp)
versions of these theorems were presented followed by some remarks on
surfaces of finite total curvature.
Introduction: PhD Thesis, Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada, November 1994
Introduction: A single expression for estimating the nominal pitting strength of steel materials, based on surface hardness, is developed from first principles for a reliability of 99% at 10 7 load cycles. It requires the hardness values to be measured in Vicker's hardness scale. The expression may be used for any steel material processed by hot rolling, cold drawing, quenching and tempering or case-hardening. The formulation incorporates a nominal design factor at 99% reliability which is estimated from a probabilistic model based on the lognormal probability density function. Pitting strength estimates from the expression are compared with those of American Gear Manufacturers Association (AGMA) estimates and data from other sources as indicated in Tables 3 and 4. The expression predicts lower values at low hardness but higher values at high hardness. The variance is between-15.21% and 10.13% for through-hardened steels. For case-hardened steels, the variances range from 14.23% to 20.26% between the estimates and available data. These variances appear to be reasonable considering the many factors involved in pitting resistance. The main advantage of this study is that pitting strength of new steel materials may be estimated for initial design sizing without long and costly contact fatigue testing which of course is necessary for design validation. Also, the estimation method developed may be applied to other materials, metallic and non-metallic. Suggestions are made for estimating some pertinent pitting strength adjustment factors when considering field or service pitting strength.
Introduction: A method for the design sizing task of cylindrical worm gearsets is presented that gives an estimate of the initial value of the normal module. Expressions are derived for the worm pitch diameter of integral and shell worms as well as for the active face width of the gear and the threaded length of the worm. An attempt is made to predict the contact strength of bronze materials against scoring resistance. Four Examples of design sizing tasks of cylindrical worm gears are carried out using the approach presented and the results are compared with previous solutions from other methods. The results for first three examples show excellent comparisons with previous solutions of American Gear Manufacturers Association (AGMA) method. The results of the fourth example are slightly more conservative than those of DIN3999 but are practically similar. Therefore, it appears that a systematic, reliable and more scientifically based method for cylindrical worm drive design sizing has been developed
Introduction: A revised Lewis bending fatigue stress capacity model for spur gears is presented and used to study the influence of mesh friction on root stress. It took the original Lewis formula and made modifications for dynamic loads, shear stress, and mesh friction in spur gear design. The study reveals that mesh friction may increase bending stress by up to 6% in enclosed cylindrical gear drives when an average mesh friction coefficient of 0.07 is assumed. A possible increase of 15% in root stress may occur in open gear drives when the mesh friction coefficient is taken as 0.15, a value considered to be representative for properly maintained open drives. To account for mesh frictional load and other factors directly influencing mesh friction, a friction load factor of 1.1 is suggested and introduced to gear service load estimation for enclosed gear drives and 1.15 for open gear drives.
Introduction: Abstract
Background:
During operation, cylindrical gearset experiences tangential, radial, and axial (helical gears only) force components that induce bending, compressive, and shear stresses at the root area of the gear tooth. Accurate estimation of the effective bending stress at the gear root is a challenge. Lewis was the first person who attempted estimating the root bending stress of spur gears with some reasonable accuracy. Various gear standards and codes in use today are modifications and improvements of the Lewis model.
Objective:
This research aims at revising the Lewis model by making adjustments for dynamic loads, shear stresses, axial bending stress for helical gears, and stress concentration factor that is independent on the moment arm of tangential or axial force component.
Methods:
An analytical approach is used in formulating a modified formula for the root bending stress in cylindrical gears starting with the original Lewis model. Intermediate expressions are developed in the process and works from many previous authors are reviewed and summarized. The new model developed is used to estimate the root bending stress in four example gearsets of 0o to 41.41o helix angle and the results are compared with those of AGMA (American Gear Manufacturers Association) formula.
Results:
Analysis from the examples shows that neglecting the radial compressive stress over-estimated the root bending stress by 5.27% on average. When shear stresses are ignored, the root bending stress is under-estimated by 7.49% on average. It is important, therefore, to account for both compressive and shear stresses in cylindrical gear root bending stress. When the root bending stress estimates from the revised Lewis model were compared with AGMA results, deviations in the range of -4.86% to 26.61% were observed. The stress estimates from the revised Lewis formulae were mostly higher than those of AGMA.
Conclusion:
The new root bending stress model uses stress concentration factors (normal and shear) that are independent of the point of load application on the gear tooth. This decoupling of stress concentration factor from the load moment arm distinguishes the new model from AGMA formula and brings bending stress analysis in gear design in line with classical bending stress analysis of straight and curved beams. The model can be used for both normal contact ratio and high contact ratio cylindrical gears.
Introduction: A numerical simulation code was used to conduct a systematic study of the effects of fuel-air equivalence ratios in the range 0.7 ? ? ? 1.4 and
compression ratio, rc = 8.0 on key operating parameters, such as pressure, rate of change of pressure, ‘/dt’ flame extinction temperature, burn rate frequency, combustion efficiency, ?b, source term, mass burn fractions and heat loss in a simulated 5.734 liter, V8 spark-ignition engine. The data shows that the burn rate characteristics of the fuel and oxidizer are qualitatively perfectly correlated. The results also show that as flame
extinction/flameout is approached, the fuel consumption rate, Rfu increases rapidly with temperature for fuel-air equivalence ratios, ? in the range
0.7 ? ? ? 1.4. The average burn rate frequency (per second), fbr(1/s) varies from 11.2 ? fbr ? 137.0 for fuel-air equivalence ratios, ? in the
range 0.7 ? ? ? 1.4 The results further show that the fastest fuel consumption rate was for fuel-air equivalence ratio, ? = 1.4 in the time
interval, t such that 0.0 ? t ? 0.61 ms while the slowest corresponds to ? – 0.7 and the corresponding time interval was 0.0 ? t ? 3.98 ms. Moreover, the data shows that for fuel-air equivalence ratios, ? in the range 0.7 ? ? ? 1.4 the fuel consumption rate increases monotonically after the initial ignition delay period. The combustion efficiency, ?b of the engine under investigation were found to be in the range of 94.1% ? ?b ? 94.4% for lean mixtures, that is, for ? < 1.0;the corresponding values of combustion efficiency, ?b for fuel-rich mixtures were in the interval 93.8% ? ?b ? 94.1%. The other results from this study are summarized in the conclusion.
Introduction: Based on the Tredgold geometric approximation, a transparent contact stress capacity model for straight bevel gears is presented. A bevel load
factor is defined which provides a kinetic link between the physical bevel gear and virtual spur gear. Three design cases of contact stress
computations from different references are carried out and compared with AGMA estimates. Differences in results vary from 2.4% to 23.4% with the
new model estimates, generally lower than AGMA values. The design sizing version of the new model is applied in two design cases.
Comparison of the service load factor values for design sizing and design verification indicates a difference of 0.76% in case 4 and -1.65% in case
5. While more design cases are necessary for further verification of the design approach presented, it may however, be concluded from the results
of our study that the design model presented appears reasonable.
Introduction: Based on the Tredgold geometric approximation, a transparent contact stress capacity model for straight bevel gears is presented. A bevel load
factor is defined which provides a kinetic link between the physical bevel gear and virtual spur gear. Three design cases of contact stress
computations from different references are carried out and compared with AGMA estimates. Differences in results vary from 2.4% to 23.4% with the
new model estimates, generally lower than AGMA values. The design sizing version of the new model is applied in two design cases.
Comparison of the service load factor values for design sizing and design verification indicates a difference of 0.76% in case 4 and -1.65% in case
5. While more design cases are necessary for further verification of the design approach presented, it may however, be concluded from the results
of our study that the design model presented appears reasonable.
Introduction: The open source Field Operation and Manipulation (OpenFOAM) software was used to investigate the performance of a fully premixed, modern high-performance 4-valve, ISO-octane, dual overhead cam (DOHC) engine with quasi-symmetric pent roof combustion chamber running at 1500 revolutions per minute. The peak pressure occurred at the TDC and had a value of about 30 bar. The results from this study show that the maximum combustion temperature occurred at approximately 95 degrees crank angle ATDC and has a volume averaged value of about 2700°K , whereas the actual computed peak temperature was found to be about 3000ºK and it occurred at grid point 12630. The other temperatures which were found to be higher than the volume averaged temperature were found to be in the range 2968.81 ° K to 2974.01 ° K and correspond to grid point positions 12630 to 12633.The flame-wrinkling factor, X = St / Su was found to be in the range 1.0 ? X ? 3.8. The dynamics of the regress variable b was accurately predicted.
Introduction: A single expression for estimating the nominal pitting strength of steel materials, based on surface hardness, is developed from first principles for a reliability of 99% at 107 load cycles. It requires the hardness values to be measured in Vicker's hardness scale. The expression may be used for any steel material processed by hot rolling, cold drawing, quenching and tempering or case-hardening. The formulation incorporates a nominal design factor at 99% reliability which is estimated from a probabilistic model based on the lognormal probability density function. Pitting strength estimates from the expression are compared with those of American Gear Manufacturers Association (AGMA) estimates and data from other sources as indicated in Tables 3 and 4. The expression predicts lower values at low hardness but higher values at high hardness. The variance is between - 15.21% and 10.13% for through-hardened steels. For case-hardened steels, the variances range from 14.23% to 20.26% between the estimates and available data. These variances appear to be reasonable considering the many factors involved in pitting resistance. The main advantage of this study is that pitting strength of new steel materials may be estimated for initial design sizing without long and costly contact fatigue testing which of course is necessary for design validation. Also, the estimation method developed may be applied to other materials, metallic and non-metallic. Suggestions are made for estimating some pertinent pitting strength adjustment factors when considering field or service pitting strength.
Introduction: Abstract: Antimicrobial resistance associated with the spread of plasmid-encoded extended-spectrum
?-lactamase (ESBL) genes conferring resistance to third generation cephalosporins is increasing
worldwide. However, data on the population of ESBL producing E. coli in different animal sources
and their antimicrobial characteristics are limited. The purpose of this study was to investigate
potential reservoirs of ESBL-encoded genes in E. coli isolated from swine, beef, dairy, and poultry
collected from different regions of the United States using whole-genome sequencing (WGS). Three
hundred isolates were typed into different phylogroups, characterized by BOX AIR-1 PCR and tested
for resistance to antimicrobials. Of the 300 isolates, 59.7% were resistant to sulfisoxazole, 49.3%
to tetracycline, 32.3% to cephalothin, 22.3% to ampicillin, 20% to streptomycin, 16% to ticarcillin;
resistance to the remaining 12 antimicrobials was less than 10%. Phylogroups A and B1 were most
prevalent with A (n = 92, 30%) and B1 (87 = 29%). A total of nine E. coli isolates were confirmed
as ESBL producers by double-disk synergy testing and multidrug resistant (MDR) to at least three
antimicrobial drug classes. Using WGS, significantly higher numbers of ESBL-E. coli were detected
in swine and dairy manure than from any other animal sources, suggesting that these may be the
primary animal sources for ESBL producing E. coli. These isolates carry plasmids, such as IncFIA(B),
IncFII, IncX1, IncX4, IncQ1, CollRNAI, Col440I, and acquired ARGs aph(6)-Id, aph(300)-Ib, aadA5,
aph(30
)-Ia, blaCTX-M-15, blaTEM-1B, mphA, ermB, catA1, sul1, sul2, tetB, dfrA17. One of the E. coli isolates
from swine with ST 410 was resistant to nine antibiotics and carried more than 28 virulence factors,
and this ST has been shown to belong to an international high-risk clone. Our data suggests that
ESBL producing E. coli are widely distributed in different animal sources, but swine and dairy cattle
may be their main reservoir.
Introduction: Abstract: Pharmaceutical wastewaters are recognized as reservoirs of antibiotic resistance genes
(ARGs) and antibiotic resistant bacteria (ARB), and also as hotspots for their horizontal gene transfer
(HGT) using mobile genetic elements. Our study employed the use of PCR analysis of metagenomic
DNA samples obtained from four pharmaceutical wastewaters using known primers to study the
prevalence of thirty-six ARGs and four MGEs active against the commonly used antibiotics in Nigeria.
The ARGs most frequently detected from the metagenomic DNA samples in each of the antibiotic
classes under study include tetracycline [tet(G)], aminoglycoside [aadA, strA and strB], chlorampheni-
col [catA1], sulphonamides [sulI and sulII], and ?-lactams and penicillins [blaOXA]. The ARGs showed
a 100% prevalence in their various environmental sources. The pharmaceutical facility PFIV showed
the highest concentration of ARGs in this study. The highest concentration for MGEs was shown by
pharmaceutical facility PFIII, positive for intl1, intl2, and IFS genes. This study highlights the wide
distribution of ARGs to the antibiotics tested in the wastewater, making pharmaceutical wastewater
reservoirs of ARGs which could potentially be transferred from commensal microorganisms to
human pathogens.
Introduction: There is increasing concern about the public health risks associated with routine and
indiscriminate use of antibacterial agents in raising livestock worldwide. Our study investigated the
antibiotics resistance of bacterial isolates obtained from four poultry farms located in a commercial
livestock farm settlement in Ilara-Epe, Lagos State, Nigeria. The antibiotic resistance pattern of readily
available and commonly used antibiotics against 92 bacterial strains isolated from the selected farms was
determined by Kirby-Bauer disc diffusion method and the minimum inhibitory concentrations (MICs) of
antibiotics for the bacterial isolates were determined by a standard two-fold serial broth microdilution
method using Mueller–Hinton broth. The results showed high resistance values to ampiclox (97.5%),
amoxicillin and zinacef (95.1%), augmentin (94.1%), and streptomycin (82.2%). Multiple drug resistance
(MDR) was observed for both Gram-negative and Gram-positive bacterial isolates at 86.3% and 90.2%
respectively. Also, 24 (26.4%) of the bacterial isolates were completely resistant to all tested antibiotics in
the study. The majority of identified bacterial isolates were Staphylococcus aureus, Escherichia coli, and
Micrococcus luteus. All the antibiotics used in this study showed high MICs values against the test
bacterial isolates. Our findings have added to existing evidence that poultry farms habour antibiotic
resistance bacteria (ARB). These ARB may pose a public health risk as they may be pathogenic to
humans and animals and also contribute to the flow of antibiotic resistance genes in the ecosystem. Hence,
there is the need to avoid the indiscriminate use of antibiotics in poultry farming, especially as growth
promoters.
Introduction: Helical bevel gears have inclined or twisted teeth on a conical surface and the common types are skew, spiral, zerol, and hypoid bevel gears. However, this study does not include hypoid bevel gears. Due to the geometric complexities of bevel gears, commonly used methods in their design are based on the concept of equivalent or virtual spur gear. The approach in this paper is based on the following assumptions, a) the helix angle of helical bevel gears is equal to mean spiral angle, b) the pitch diameter at the backend is defined as that of a helical gear, and c) the Tredgold’s approximation is applied to the helical gear. Upon these premises, the contact stress capacity of helical bevel gears is formulated in explicit design parameters. The new contact stress capacity model is used to estimate the contact stress in three gear systems for three application examples
and compared with previous solutions. Differences between the new estimated results and the previous solutions vary from -3% and -11%, with the new estimates being consistently but marginally or slightly lower than the previous solution
values. Though the differences appear to be small, they are significant because the durability of gears is strongly influenced by the contact stress. For example, a 5% reduction in contact stress may result in almost 50% increase in durability in
some steel materials. The equations developed do not apply to bevel crown gears.
Introduction: Using real interest rate parity (RIP), this paper evaluates the extent of African financial market integration into the global market selecting the U.S, EU and China as reference countries. To test for RIP, we apply the linear, non-linear and panel data unit root and stationary tests. The findings show that RIP condition holds in African countries, indicating that African financial markets are integrated into the global market. The results, however, suggest more integration with China than the U.S and EU. While the findings from the linear unit root tests confirm RIP in 9 out of 10 countries with respect to the U.S. and EU, it supports RIP condition for the 10 countries using China as the base. The non-linear
KSS tests result show that RIP conditions hold in 8 of the 10 Africa countries. Lastly, the results from panel data unit root tests also validate the RIP condition in Africa JEL Classification: F36; G15; Keywords: Real interest parity; financial integration; real interest rate differential; African countries; unit root tests
Introduction: Using real interest rate parity (RIP), this paper evaluates the extent of African financial market integration into the global market selecting the U.S, EU and China as reference countries. To test for RIP, we apply the linear, non-linear and panel data unit root and stationary tests. The findings show that RIP condition holds in African countries, indicating that African financial markets are integrated into the global market. The results, however, suggest more integration with China than the U.S and EU. While the findings from the linear unit root tests confirm RIP in 9 out of 10 countries with respect to the U.S. and EU, it supports RIP condition for the 10 countries using China as the base. The non-linear
KSS tests result show that RIP conditions hold in 8 of the 10 Africa countries. Lastly, the results from panel data unit root tests also validate the RIP condition in Africa JEL Classification: F36; G15; Keywords: Real interest parity; financial integration; real interest rate differential; African countries; unit root tests
Introduction: This paper is anchored on the premise that the late take-off of Political Communication in Nigeria is partly due to the neglect of the discipline by the political architects of Nigeria, the nationalists and the British colonizing authorities. As at today, it is very rare to find scholarly
publications in which the architects of Nigeria ever discussed or prescribed political communication as one of the basic steps to nurture the new democracy at the time of independence. Yet, in the context of Perloff (2014:29) “democracy is political communication”. North (1967:301) on his part says “politics cannot exist without communication nor could wars be fought”. Through a case study approach the study found out
that none of the existing universities in Nigeria offers PhD programme in Political Communication and therefore suggested that interested universities in Nigeria should formally apply to the NUC requesting approval to formally mount the programme as part of strategic steps to strengthen the country’s nascent democracy. The study employed the World-System theory as well as Agenda - setting theory as theoretical poles.
Keyword: Political Communication, Democracy, Nation-Building.
Introduction: This study tests the response of trade balance of Nigeria and South Africa to symmetric and asymmetric change in oil price and exchange rate using disaggregated monthly data for the period of 1995M01 to 2018M12 within the framework of Autoregressive Distributed Lag (ARDL) model and found that increases in oil price significantly produced symmetrical negative effects on trade balance of Nigeria in the long run and insignificant negative effect on trade balance of South Africa in the short run. Also, exchange rate depreciation significantly affected trade balance of Nigeria but showed insignificant effects on trade balance of South Africa. Finally, accounting for asymmetry in oil price and exchange
rate may be implausible in predicting the dynamics of trade balance of the two countries within the time span of the study. We therefore recommend increased diversification of the economy and pursuant of exchange stability policy to achieve favorable balance of trade.
Keywords: Trade balance; Oil price; Exchange rate; Asymmetries; ARDL
Introduction: This study tests the response of trade balance of Nigeria and South Africa to symmetric and asymmetric change in oil price and exchange rate using disaggregated monthly data for the period of 1995M01 to 2018M12 within the framework of Autoregressive Distributed Lag (ARDL) model and found that increases in oil price significantly produced symmetrical negative effects on trade balance of Nigeria in the long run and insignificant negative effect on trade balance of South Africa in the short run. Also, exchange rate depreciation significantly affected trade balance of Nigeria but showed insignificant effects on trade balance of South Africa. Finally, accounting for asymmetry in oil price and exchange
rate may be implausible in predicting the dynamics of trade balance of the two countries within the time span of the study. We therefore recommend increased diversification of the economy and pursuant of exchange stability policy to achieve favorable balance of trade.
Keywords: Trade balance; Oil price; Exchange rate; Asymmetries; ARDL
Introduction: The study investigates the determinants of manufacturing sub-sector output growth in Nigeria between 1981 and 2020 with time series data extracted from Central Bank of Nigeria data base. The analysis was carried out using the ARDL technique in view of the fact that all the variables were not stationary at the same order. Anchoring on AK-type neoclassical growth frameworks, the short run Cointegration results
revealed that manufacturing industries capacity utilization rates and commercial banks credit to themanufacturing sub-sector positively influenced manufacturing output, while inflation rate and exchange rate had negative coefficients. The study also revealed that increase in capital expenditure, credit to manufacturers and electricity consumption positively spurred manufacturing output in the long run. The
authors therefore recommend that increased capital expenditure by the government to revamp the power sector and enhanced access to affordable credit from banks by manufacturers would guarantee Nigerian manufacturing sub-sector long term development.
Introduction: The study investigates the determinants of manufacturing sub-sector output growth in Nigeria between 1981 and 2020 with time series data extracted from Central Bank of Nigeria data base. The analysis was carried out using the ARDL technique in view of the fact that all the variables were not stationary at the same order. Anchoring on AK-type neoclassical growth frameworks, the short run Cointegration results
revealed that manufacturing industries capacity utilization rates and commercial banks credit to themanufacturing sub-sector positively influenced manufacturing output, while inflation rate and exchange rate had negative coefficients. The study also revealed that increase in capital expenditure, credit to manufacturers and electricity consumption positively spurred manufacturing output in the long run. The
authors therefore recommend that increased capital expenditure by the government to revamp the power sector and enhanced access to affordable credit from banks by manufacturers would guarantee Nigerian manufacturing sub-sector long term development.
Introduction: This study investigated the effect of financial reporting quality on economic value added of corporate firms in Nigeria for the period of 2008-2020. An ex-post facto research design with purposive sampling was applied in selecting ten (10) different listed firms cutting across nine (9) sectors (agricultural, construction and real estate, consumer goods, financial, healthcare, ICT, services, industrial, and oil and gas) in Nigerian Stock Exchange. The validity and reliability of the data obtained were premised on the scrutiny of the external auditors of the financial statements of the selected companies. Descriptive and inferential (panel data) regression analysis carried out and the study found that financial reporting quality had a positive significant effect on economic value added. It recommended that investors should watch the consistencies of the reported earnings in financial statements as discretionary earnings could be reported by managers in order to cover up incompetence and in meeting with investors’ performance expectations.
Keywords: Accruals quality, Earnings quality, Earnings smoothness, Earnings persistence, Economic value added, Financial reporting
Introduction: This study investigated the effect of financial reporting quality on economic value added of corporate firms in Nigeria for the period of 2008-2020. An ex-post facto research design with purposive sampling was applied in selecting ten (10) different listed firms cutting across nine (9) sectors (agricultural, construction and real estate, consumer goods, financial, healthcare, ICT, services, industrial, and oil and gas) in Nigerian Stock Exchange. The validity and reliability of the data obtained were premised on the scrutiny of the external auditors of the financial statements of the selected companies. Descriptive and inferential (panel data) regression analysis carried out and the study found that financial reporting quality had a positive significant effect on economic value added. It recommended that investors should watch the consistencies of the reported earnings in financial statements as discretionary earnings could be reported by managers in order to cover up incompetence and in meeting with investors’ performance expectations.
Keywords: Accruals quality, Earnings quality, Earnings smoothness, Earnings persistence, Economic value added, Financial reporting
Introduction: The aim of this work was to report on molecular identification and technological properties of the yeast flora isolated from spontaneously fermented cassava waste pulp. This was done with a view of obtaining yeast strains that could be used as a starter culture for the fermentation of cassava waste pulp. Molecular identification was based on the nucleotide sequence of the ITS region of the genomic DNA of the yeast isolates while the technological properties evaluated include linamarase (U/mL), gelatinase, and haemolytic activity; growth at pH 2.5 and tolerance to 2 % bile salt. All the representative five isolated yeasts were identified as Geotrichum silvicola KLP04 – KLP08. The isolates exhibited linamarase activity ranging between 3.3 and 4.2 with strain KLP04 having the highest value and strain KLP05 the least. None of the isolates demonstrated gelatinase and haemolytic activity except strain KLP08 which was partially haemolytic. All the examined yeasts exhibited good growth at pH 2.5, with strain KLP08 having the highest viable counts of 4.1 log10cfu/ml and strain KLP04 the least value of 3.5 log10cfu/ml after 72 h of growth. All the identified yeasts showed strain-specific tolerance to 2% bile salt with strain KLP04 having the highest viable count of 4.3 log10cfu/ml and strain KLP08 the least value of 2.2 log10cfu/ml at the end of 72 h of incubation. Based on all the examined technological properties, Candida silvicola KLP04 strain had the highest potential to be considered for starter culture for the fermentation of cassava waste pulp.
Introduction: The aim of this work was to report on molecular identification and technological properties of the yeast flora isolated from spontaneously fermented cassava waste pulp. This was done with a view of obtaining yeast strains that could be used as a starter culture for the fermentation of cassava waste pulp. Molecular identification was based on the nucleotide sequence of the ITS region of the genomic DNA of the yeast isolates while the technological properties evaluated include linamarase (U/mL), gelatinase, and haemolytic activity; growth at pH 2.5 and tolerance to 2 % bile salt. All the representative five isolated yeasts were identified as Geotrichum silvicola KLP04 – KLP08. The isolates exhibited linamarase activity ranging between 3.3 and 4.2 with strain KLP04 having the highest value and strain KLP05 the least. None of the isolates demonstrated gelatinase and haemolytic activity except strain KLP08 which was partially haemolytic. All the examined yeasts exhibited good growth at pH 2.5, with strain KLP08 having the highest viable counts of 4.1 log10cfu/ml and strain KLP04 the least value of 3.5 log10cfu/ml after 72 h of growth. All the identified yeasts showed strain-specific tolerance to 2% bile salt with strain KLP04 having the highest viable count of 4.3 log10cfu/ml and strain KLP08 the least value of 2.2 log10cfu/ml at the end of 72 h of incubation. Based on all the examined technological properties, Candida silvicola KLP04 strain had the highest potential to be considered for starter culture for the fermentation of cassava waste pulp.
Introduction: This study was aimed at exploiting the nutritive and preservative potentials of leafy vegetables on egg quality and shelf-life. 189 Lohman Brown Classic point-of-lay chickens at sixteen weeks with average weight of 1550-1620g were used in a 12-week feeding trials. The birds were allotted on weight equalization basis to seven feeding treatments (T1-T7). T1 was white maize without additive, T2 was yellow maize without additives while T3-T7 were white maize, fortified with synthetic yolk colourant (T3); fortified with Corchorus olitorius (T4); fortified with Talinum fruticosum (T5); fortified with Chromolaena odorata (T6); and fortified with a blend of Corchorus, Talinum and Chromolaena at 0.33% each (T7) respectively. Results obtained from this study showed that the dietary treatments had effects on the performance parameters. Chickens on T3 recorded the highest (P<0.05) Hen-day production followed by T1 and T7 with values ranging from 69.95-89.57%. Similar pattern was observed with Feed/dozen egg. Chickens on T2 had the heaviest egg (63.41 g) followed by T3 (59.45 g) and T1 (58.56 g). The pH values of eggs from T1, T2, T4 and T6 increased as the eggs age while it decreases in T3 and T7. The microbial load in eggs from chickens fed with T1 and T5 increased, T3 remain stable whereas eggs from T2, T4, T6 and T7 decreased with storage days. This study revealed that the blend of Corchorus, Talinum and Chromolaena can be used as alternative source of feed additive without deleterious effects on laying performance, quality characteristics and storage life.
Introduction: This study was aimed at exploiting the nutritive and preservative potentials of leafy vegetables on egg quality and shelf-life. 189 Lohman Brown Classic point-of-lay chickens at sixteen weeks with average weight of 1550-1620g were used in a 12-week feeding trials. The birds were allotted on weight equalization basis to seven feeding treatments (T1-T7). T1 was white maize without additive, T2 was yellow maize without additives while T3-T7 were white maize, fortified with synthetic yolk colourant (T3); fortified with Corchorus olitorius (T4); fortified with Talinum fruticosum (T5); fortified with Chromolaena odorata (T6); and fortified with a blend of Corchorus, Talinum and Chromolaena at 0.33% each (T7) respectively. Results obtained from this study showed that the dietary treatments had effects on the performance parameters. Chickens on T3 recorded the highest (P<0.05) Hen-day production followed by T1 and T7 with values ranging from 69.95-89.57%. Similar pattern was observed with Feed/dozen egg. Chickens on T2 had the heaviest egg (63.41 g) followed by T3 (59.45 g) and T1 (58.56 g). The pH values of eggs from T1, T2, T4 and T6 increased as the eggs age while it decreases in T3 and T7. The microbial load in eggs from chickens fed with T1 and T5 increased, T3 remain stable whereas eggs from T2, T4, T6 and T7 decreased with storage days. This study revealed that the blend of Corchorus, Talinum and Chromolaena can be used as alternative source of feed additive without deleterious effects on laying performance, quality characteristics and storage life.
Introduction: Background: The Sungbo Eredo Monument is an ancient public work with a system of defensive walls and ditches located in Eredo Local Council Development Area of Epe, Lagos State, southwest Nigeria. A huge section of the monument cuts through the Augustine University campus, forming two-sided vertical walls with a deep ridge in-between. The objective of this investigative study is to determine the microbial profile of soil samples from the monument in the University campus.
Introduction: Background: The Sungbo Eredo Monument is an ancient public work with a system of defensive walls and ditches located in Eredo Local Council Development Area of Epe, Lagos State, southwest Nigeria. A huge section of the monument cuts through the Augustine University campus, forming two-sided vertical walls with a deep ridge in-between. The objective of this investigative study is to determine the microbial profile of soil samples from the monument in the University campus.
Introduction: Background: The Sungbo Eredo Monument is an ancient public work with a system of defensive walls and ditches located in Eredo Local Council Development Area of Epe, Lagos State, southwest Nigeria. A huge section of the monument cuts through the Augustine University campus, forming two-sided vertical walls with a deep ridge in-between. The objective of this investigative study is to determine the microbial profile of soil samples from the monument in the University campus.
Introduction: Nutritional and rheological properties of starter-produced Lafun, an African fermented cassava product
Introduction: Antibacterial Activity of Lactic Acid Bacteria Isolated from Fermented Cereal Products Against Organisms Implicated in Gastrointestinal Tract Infections.
Introduction: Lafun is one of the regularly consumed fermented cassava food in many parts of West Africa, though it is nutritionally inferior in terms of protein and mineral contents. In the present work, the possibility of nutritional enrichment of lafun by controlled fermentation of cassava root tuber using Lactobacillus plantarum and Saccharomyces boulardii was carried out. Three samples of lafun were produced using the two organisms as monoculture and mixed culture while the fourth sample that was obtained from spontaneous fermentation served as control. The pH and titratable acidity (TA) (mg lactic acid/g ) of the fermenting roots were measured at 0th and 72nd hour of fermentation. Standard methods were used for the determination of proximate parameters such as crude protein, ash, lipids, crude fibre, moisture content and carbohydrate. All samples were analysed for phosphorus, calcium, magnesium, potassium, sodium, manganese, iron, copper, and zinc. The pH changes observed for Lactobacillus plantarum fermentation (LPF), Saccharomyces boulardii fermentation (SBF), mixed culture fermentation (MCF) and spontaneous fermentation (SF) were from 6.2 to 4.3, 6.2 - 5.3, 6.1 - 4.6, and 6.2 - 4.9 respectively while the TA increased from 0.6 in all samples to 9.9, 3.6, 8.4 and 7.0 in LPF, SBF, MCF, and SF respectively. Lafun sample obtained from SBF had significantly higher (p < 0 .01) proximate values (protein: 1.70%; ash: 15.20%; crude fibre: 5.80%) than those obtained from SF (protein: 1.25%; ash: 12.42%; crude fibre: 1.41%), LPF (protein: 1.13%; ash: 2.26%; crude fibre: 3.14%), and MCF (protein: 1.60%; ash: 11.53%; crude fibre: 4.22%). Of all the four fermentation setups, SBF had the highest P (0.07%), Ca (0.80%), K (1.86%), Mn (10.39 ppm), Cu (4.42 ppm), and Zn(16.91 ppm) contents. This study shows a potential for nutritional improvement of lafun using Saccharomyces boulardii as starter culture.
Introduction: Lafun is one of the regularly consumed fermented cassava food in many parts of West Africa, though it is nutritionally inferior in terms of protein and mineral contents. In the present work, the possibility of nutritional enrichment of lafun by controlled fermentation of cassava root tuber using Lactobacillus plantarum and Saccharomyces boulardii was carried out. Three samples of lafun were produced using the two organisms as monoculture and mixed culture while the fourth sample that was obtained from spontaneous fermentation served as control. The pH and titratable acidity (TA) (mg lactic acid/g ) of the fermenting roots were measured at 0th and 72nd hour of fermentation. Standard methods were used for the determination of proximate parameters such as crude protein, ash, lipids, crude fibre, moisture content and carbohydrate. All samples were analysed for phosphorus, calcium, magnesium, potassium, sodium, manganese, iron, copper, and zinc. The pH changes observed for Lactobacillus plantarum fermentation (LPF), Saccharomyces boulardii fermentation (SBF), mixed culture fermentation (MCF) and spontaneous fermentation (SF) were from 6.2 to 4.3, 6.2 - 5.3, 6.1 - 4.6, and 6.2 - 4.9 respectively while the TA increased from 0.6 in all samples to 9.9, 3.6, 8.4 and 7.0 in LPF, SBF, MCF, and SF respectively. Lafun sample obtained from SBF had significantly higher (p < 0 .01) proximate values (protein: 1.70%; ash: 15.20%; crude fibre: 5.80%) than those obtained from SF (protein: 1.25%; ash: 12.42%; crude fibre: 1.41%), LPF (protein: 1.13%; ash: 2.26%; crude fibre: 3.14%), and MCF (protein: 1.60%; ash: 11.53%; crude fibre: 4.22%). Of all the four fermentation setups, SBF had the highest P (0.07%), Ca (0.80%), K (1.86%), Mn (10.39 ppm), Cu (4.42 ppm), and Zn(16.91 ppm) contents. This study shows a potential for nutritional improvement of lafun using Saccharomyces boulardii as starter culture.
Introduction: Lactic acid bacteria (LAB) and yeasts involved in Ogi production have been greatly studied. However, it is important to consider the technological roles of these organisms and their contribution to product quality and safety. LAB and yeasts were isolated from three varieties of Ogi and identified using biochemical characteristics and API 50CHL and API 20C AUX kits. Technological properties including acidification activity, production of ?-amylase, phytate degradation, tolerance to 2% bile salt and haemolytic activity were tested in the isolates. Fifteen isolates of LAB obtained included Lactobacillus brevi, L. casei and L. plantarum while the yeasts were Candida famata, C. gulliermondii, C. lusitaniae and Cryptococcus humicola. Isolates WML482 and YMY483 with ?pH of 1.62 and 2.10 respectively showed the most rapid acidification. Four isolates of LAB showed ?-amylase activity. The LAB and yeast isolates differed in their ability to degrade phytate but were all tolerant to 2% bile salt with the highest growth of 8.41 cfu/mL and 8.42 cfu/mL observed at 72 h in isolates RSL483 and YMY001 respectively. None of the isolates showed ?-haemolysis. The isolates from this study possess notable technological properties which position them as good starters for production of Ogi with better and safe qualities.
Introduction: Lactic acid bacteria (LAB) and yeasts involved in Ogi production have been greatly studied. However, it is important to consider the technological roles of these organisms and their contribution to product quality and safety. LAB and yeasts were isolated from three varieties of Ogi and identified using biochemical characteristics and API 50CHL and API 20C AUX kits. Technological properties including acidification activity, production of ?-amylase, phytate degradation, tolerance to 2% bile salt and haemolytic activity were tested in the isolates. Fifteen isolates of LAB obtained included Lactobacillus brevi, L. casei and L. plantarum while the yeasts were Candida famata, C. gulliermondii, C. lusitaniae and Cryptococcus humicola. Isolates WML482 and YMY483 with ?pH of 1.62 and 2.10 respectively showed the most rapid acidification. Four isolates of LAB showed ?-amylase activity. The LAB and yeast isolates differed in their ability to degrade phytate but were all tolerant to 2% bile salt with the highest growth of 8.41 cfu/mL and 8.42 cfu/mL observed at 72 h in isolates RSL483 and YMY001 respectively. None of the isolates showed ?-haemolysis. The isolates from this study possess notable technological properties which position them as good starters for production of Ogi with better and safe qualities.
Introduction: Lactic acid bacteria (LAB) and yeasts involved in Ogi production have been greatly studied. However, it is important to consider the technological roles of these organisms and their contribution to product quality and safety. LAB and yeasts were isolated from three varieties of Ogi and identified using biochemical characteristics and API 50CHL and API 20C AUX kits. Technological properties including acidification activity, production of ?-amylase, phytate degradation, tolerance to 2% bile salt and haemolytic activity were tested in the isolates. Fifteen isolates of LAB obtained included Lactobacillus brevi, L. casei and L. plantarum while the yeasts were Candida famata, C. gulliermondii, C. lusitaniae and Cryptococcus humicola. Isolates WML482 and YMY483 with ?pH of 1.62 and 2.10 respectively showed the most rapid acidification. Four isolates of LAB showed ?-amylase activity. The LAB and yeast isolates differed in their ability to degrade phytate but were all tolerant to 2% bile salt with the highest growth of 8.41 cfu/mL and 8.42 cfu/mL observed at 72 h in isolates RSL483 and YMY001 respectively. None of the isolates showed ?-haemolysis. The isolates from this study possess notable technological properties which position them as good starters for production of Ogi with better and safe qualities.
Introduction: Meloidogyne enterolobii is a highly polyphagous tropical species of root-knot nematode. It has been recorded causing major damage to a range of economically important crops and is increasingly recorded from new locations. Its morphological similarity and overlap of characteristics with other commonly occurring species, especially M. incognita, has confused its diagnosis using morphometrics. Cassava (Manihot esculenta) is an important crop across the tropics, including in Africa, where it is among the most important root and tuber crops for food security. Cassava can be heavily infected by root knot nematodes, which can incur heavy production losses. The main species known to affect cassava are M. incognita and M. javanica (Coyne and Affokpon 2018). With the exception of one report of M. enterolobii morphologically identified from cassava roots during a survey in Brazil (Rosa et al. 2014), there is no record with molecular confirmation of it infecting the crop. In the absence of any molecular or isozyme confirmation, diagnosis of M. enterolobii is difficult. In the current study, the species responsible for substantial galling damage on several cassava roots growing in Ibadan, Nigeria (7°22?39? N; 3°54?21? E), were diagnosed.
Introduction: Local Government Autonomy and the 1999 Constitution of the Federal Republic of Nigeria: A Critical Appraisal
Introduction: Credible Elections and Challenges of Sustainable Democracy in Nigeria's Fourth Republic in Igbinedion University Journal of Arts and Social Sciences Vol. 2, No. 1
Introduction: Conceptualising Development Cooperation in Third World Development Strategies: Decades of Fascination and Frustrations, 2013
Introduction: Concept and Origin of Public Private Partnership in Third World Development Strategies: Decades of Fascination and Frustrations, 2013
Introduction: Concept and Theories of Peace in Law, Conflicts and Human Rights in Africa, 2013.
Introduction: This paper is the outcome of a rigorous examination of notable print media that were visible online
in Nigeria on the professional application of Background Information in their reportage of news
stories, when COVID-19 broke out in 2019 in China and 2020 in Nigeria. This study is strongly
of the view that if the Nigerian press had professionally applied Background Information when
the pandemic broke out, with reference to similar occurrences in the past, especially the pandemic
of 1918, the response of the public would have been different when government rolled out
measures to contain the pandemic in Nigeria and the 3,053 deaths recorded in Nigeria from
COVID-19 could have been avoided. Using Agenda setting theory, as well as Uses and
gratifications theory of the press, as theoretical underpinning with historical methodological
approach, the paper found out that the newspapers failed their audiences due to their adherence
to the discredited 5Ws + H of reporting which is in vogue in Nigeria and therefore advocates the
need for the press to embrace the 3D dimension of news reporting which makes it mandatory for
the media to provide comprehensive background information by probing the who behind the who,
the what behind the what, and the why behind the why, as well as the how behind the how.
Introduction: The study examined the effect of organizational culture on firm innovativeness in General
Hospital, Epe, Lagos State. Survey research design was employed and primary data obtained via
the use of self-administered questionnaire. Simple random sampling was utilized and 171 staff
from different departments of the hospital, made up the sample size. Structural-functionalism and
innovative diffusion theories underpinned the study. Descriptive statistics and simple regression
analysis were applied for data analysis. The findings revealed that bureaucratic culture had no
significant effect on process innovation (? = 0.193, t = 0.846, p>0.05). Supportive culture had
significant effect on organizational innovation (? = 0.816, t = 4.440, p<0.05). Innovative culture
had significant effect on market innovation of the hospital (? = 0.409, t = 3.085, p<0.05). The
study concludes that the practice of bureaucratic culture, supportive culture and innovative culture
leads to improved business models, encourage employees’ creative abilities, enhanced
technologies and better ways of attracting and retaining customers.
Introduction: Nigeria and China have had a long bilateral trade relation. Outside the Middle East, Nigeria is a major export destination of China. This study investigates the response of Nigeria’s trade balance to the dynamics of China’s trade balance using monthly time series data spanning
1995M01 to 2019M12. We employed the linear and nonlinear Autoregressive distributed lag models and discovered that China’s trade balance significantly affects Nigeria’s trade balance in the short run and long run. Also, the lag values of China’s trade balance significantly explain
current value of Nigeria’s trade balance in the long run. While we found changes in Nigerian exchange rate having increasing effects on the country’s trade balance in the long run, China’s exchange rate appreciation and depreciation appeared to hurt Nigeria’s trade balance in the
short run. We further found no evidence of asymmetric effects of oil price, the Nigeria exchange rate, and China’s exchange rate on Nigeria’s trade balance in the short and long run. We therefore, suggest that Nigeria’s investors and the government should consider China’s trade balance and exchange rate behaviours in trading decisions.
Introduction:
This paper, “Masculinities, Hierarchical Tyranny of Traits, and Statuses examines Chinua
Achebe’s Things Fall Apart (1958), Arrow of God (1964) and Buchi Emecheta’s The Joys of
Motherhood (1979), and Second Class Citizen (1974), and the Slave Girl (1977). The Methodology
adopted is anchored on aspects of Sigmund Freud’s Psychoanalytic theory and Ideology in
Marxist theory. In spite of the generally held views that gender is both biologically innate and
socio-culturally determined; this paper argues that there is a psycho-social conspiracy between
traits and statuses to tyrannize the masculine subject in the novels examined here. The study
reveals that the desire of the masculine subject to comply with social-cultural expectations in traits
and roles attached to statuses usually creates unmanageable conflicts and crises in the intra- and
inter-personal relationships of the masculine subject. The study concludes that no one male
character can be hegemonic in every attribute or status. Therefore, every male deserves respect
in any area he is very successful but the society is unforgiving and will not permit this respect.
Based on these findings, the study recommends that there is need to re-examine the global view
that hegemonic and subordinated hierarchies of masculinities can be determined in absolute
terms.
Introduction:
This paper, “Masculinities, Hierarchical Tyranny of Traits, and Statuses examines Chinua
Achebe’s Things Fall Apart (1958), Arrow of God (1964) and Buchi Emecheta’s The Joys of
Motherhood (1979), and Second Class Citizen (1974), and the Slave Girl (1977). The Methodology
adopted is anchored on aspects of Sigmund Freud’s Psychoanalytic theory and Ideology in
Marxist theory. In spite of the generally held views that gender is both biologically innate and
socio-culturally determined; this paper argues that there is a psycho-social conspiracy between
traits and statuses to tyrannize the masculine subject in the novels examined here. The study
reveals that the desire of the masculine subject to comply with social-cultural expectations in traits
and roles attached to statuses usually creates unmanageable conflicts and crises in the intra- and
inter-personal relationships of the masculine subject. The study concludes that no one male
character can be hegemonic in every attribute or status. Therefore, every male deserves respect
in any area he is very successful but the society is unforgiving and will not permit this respect.
Based on these findings, the study recommends that there is need to re-examine the global view
that hegemonic and subordinated hierarchies of masculinities can be determined in absolute
terms.
Introduction: This study investigated the contributions of the four agricultural sub-sectors in Nigeria to economic growth and poverty reduction using time series data from 1981 to 2020. It is based on the premise that agriculture is the engine of growth and a potent vehicle for poverty reduction
particularly in developing countries where most of the populace earn their living directly or indirectly from the sector. The Fully Modified Ordinary Least Square (FMOLS) model was adopted for data analysis. The variables used include: Nigeria’s real total gross domestic product
(RGDP), the contributions of the different sub-sectors of agriculture (livestock, crops, fishery and forestry) to total gross domestic product, poverty headcount, and total loans guaranteed to the agricultural sector by commercial banks in Nigeria. Findings from this study validated the above claims as all the four sub-sectors of agriculture contributed positively and significantly to growth in real GDP, and reduction in poverty headcount with the exception of the livestock subsector. The authors believe that increased effort to grow the livestock sub-sector, will further increase the capacity of the agricultural sector to reduce poverty in Nigeria. Agricultural credit was also found to contribute to poverty reduction and real output growth in Nigeria thereby, justifying the need for increased access to credit by farmers.