Morphological Diversity and Cytological Studies in Some Accessions of Vigna vexillata (L.) A. Richard

Aim: The objectives of this study were to characterize and evaluate intraspecific relationship among twenty-six accessions of Vigna vexillata (L.) and work out interrelationship among the morphological traits which could be used for genetic improvement of cowpea, V. unguiculata (L.) Walp. Study Design: Field experiment was laid out in blocks of five buckets per accession in a row giving a total of 260 plants. Place and Duration of Study: At the experimental field of the Department of Biological Sciences, Covenant University, Ota, Ogun state, Nigeria, during the dry planting season (September – December, 2012). Methodology: A total of 26 traits comprising 18 quantitative and 8 qualitative traits of the vegetative, floral, pod and seed were evaluated using descriptive statistics, Pearson Correlation Coefficient (PCC), Principal Component Analysis (PCA) and Cluster Analysis (CA). Mitotic chromosome counts and meiotic behaviour were studied using root tip cells and pollen mother cells from young flower buds. Results: The analysis of variance showed that all quantitative morphological characters were significantly different among the accessions (P = 0.01) except stipule length and width. There were significant correlations among characters such as calyx lobe length, standard petal length and width, peduncle length, days to 50% flowering, days to 50% pod maturity, pod length and width, number of locules per pod, number of seeds per pod, and 100-seed weight which could be used for breeding and conservation purposes. The first six principal components accounted for 89.84% of the total variance. The cluster analysis segregated the 26 accessions into three main clusters; cluster I (15 accessions), cluster II (10 accessions) and cluster III (1 accession). Mitotic chromosome counts of 2n = 22 were recorded for all the accessions and meiosis was observed to be normal with the formation of eleven bivalents (n = 11). Conclusion: The intraspecific variabilities indicates plasticity in the genomes of the studied accessions, with high correlations among the morphological characters which are common to all accessions, thus justifying their grouping as a species. The morphological and reproductive attributes displayed by accessions TVnu93 and TVnu97 in terms of plant vigour, early flowering and pod maturity, longer pods and relatively high 100-seed weight made them good potential candidates in breeding for host plant resistance in cowpea

Dementia incidence declined in African-Americans but not in Yoruba

INTRODUCTION: To compare dementia incidence of African-American and Yoruba cohorts aged ≥70 years enrolled in 1992 and 2001. METHODS: African-Americans residing in Indianapolis and Yoruba in Ibadan, Nigeria without dementia were enrolled in 1992 and 2001 and evaluated every 2-3 years until 2009. The cohorts consist of 1440 African-Americans, 1774 Yoruba in 1992 and 1835 African-Americans and 1895 Yoruba in the 2001 cohorts aged ≥70 years. RESULTS: In African-Americans, dementia and Alzheimer's disease (AD) incidence rates were significantly lower in 2001 than 1992 for all age groups except the oldest group. The overall standardized annual dementia incidence rates were 3.6% (95% confidence interval [CI], 3.2%-4.1%) in the 1992 cohort and 1.4% (95% CI, 1.2%-1.7%) in the 2001 cohort. There was no significant difference in dementia or AD incidence between the Yoruba cohorts. DISCUSSION: Future research is needed to explore the reasons for the differential changes in incidence rates in these two populations

Beneficial effects of omega-3 fatty acid on dyslipidemia in organs of alloxan-induced diabetic rats

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

Moisture Adsorption Characteristics of Ginger (Zingiber officinale) Powders

The adsorption equilibrium moisture content of the powders of peeled ginger (PGP) and unpeeled ginger (UGP) at 20, 30, 40 and 50 °C were investigated using static gravimetric method. The data were fitted to various sorption models. The thermodynamics of water vapour adsorption of the powders was also investigated at moisture contents in the range of 8 to 20 g H2O/100 g solid. Both powders exhibited the type II isotherms. The equilibrium moisture content of the powder decreased with increasing temperature and increased with water activity. The monolayer moisture content also decreased with an increase in temperature. The powder of peeled ginger was less hygroscopic than that of unpeeled ginger and is therefore more shelf- stable. The GAB, Henderson and Oswin equations accurately fitted experimental sorption data (RMS < 10 %); however, the GAB model gave the best fit. The net isosteric heats (ΔHst) of sorption generally decreased with increasing moisture content. The ΔHst of UGP was generally higher than that of PGP. The isosteric heat of the first molecule (ΔHo) of UGP was also higher (72.042 kJ/mol) than that of the PGP (59.695 kJ/mol). On the other hand, the characteristic moisture content (Mch) of UGP was lower (4.058 g H2O/100g solid) than its equivalent for PGP (4.155 g H2O/100 g solid). The values of ΔHo and Mch indicated the relative low moisture affinity of UGP compared to PGP. The enthalpies of sorption for PGP were lower than UGP. Conversely, the entropy of sorption of UGP was higher (6.233 to 158.180 J/mol-K) than that of PGP (2.496 to 125.721 J/mol-K)

Genetic Influences on Plasma Homocysteine Levels in African Americans and Yoruba Nigerians.

Plasma homocysteine, a metabolite involved in key cellular methylation processes seems to be implicated in cognitive functions and cardiovascular health with its high levels representing a potential modifiable risk factor for Alzheimer’s disease (AD) and other dementias. A better understanding of the genetic factors regulating homocysteine levels, particularly in non-white populations, may help in risk stratification analyses of existing clinical trials and may point to novel targets for homocysteine-lowering therapy. To identify genetic influences on plasma homocysteine levels in individuals with African ancestry, we performed a targeted gene and pathway-based analysis using a priori biological information and then to identify new association performed a genome-wide association study. All analyses used combined data from the African American and Yoruba cohorts from the Indianapolis-Ibadan Dementia Project. Targeted analyses demonstrated significant associations of homocysteine and variants within the CBS (Cystathionine beta-Synthase) gene. We identified a novel genome-wide significant association of the AD risk gene CD2AP (CD2-associated protein) with plasma homocysteine levels in both cohorts. Minor allele (T) carriers of identified CD2AP variant (rs6940729) exhibited decreased homocysteine level. Pathway enrichment analysis identified several interesting pathways including the GABA receptor activation pathway. This is noteworthy given the known antagonistic effect of homocysteine on GABA receptors. These findings identify several new targets warranting further investigation in relation to the role of homocysteine in neurodegeneration

Investigating the Impact of Learners Emotions on Academic Performance and Motivation using Ethnography

Researches has shown that students experience a wide range of emotions in class and while doing test and this thus have consequences on learning and achievement. This research therefore tried to find out the effect of achievement pressure and expectation of failure on students’. Students’ motivation and academic performance were examined with a sample of twenty-four students of Computer Science in 200 level. The results of the investigation revealed that students' motivation and action are settings to consider when investigating the different types of emotions students experience while in class and doing test. The results also revealed that there is significant difference between class-related emotions and test-related emotions on students’ hypotheses for patterns within and between domains

Economic growth, air pollution and health outcomes in Nigeria: A moderated mediation model

The third of the sustainable development goals is to ensure healthy living and promote well-being for all by 2030. The Nigerian government has made several efforts at achieving this goal. Economic experts have projected that the Nigerian economy must grow at a minimum rate of 6–8% yearly to catch up with global development and contribute positively to goals set by nations of the world. However, the attainment of high levels of economic growth could have implications for the attainment of other development objectives in the economy. One of such implications is pollution of the environment caused through productive activities. In carrying out productive activities, a cycle from production to consumption occurs to affect the release of emissions into the atmosphere and environment which in turn hampers health stability. In order to assess the cyclical effects of these economic relationships, this study adopted the use of a moderated mediation model. The model helped in the explanation of interactions among economic growth, air pollution and health performance. The interactions were analyzed with PROCESS macro, an analytical tool developed by Hayes. The study found air pollution and government expenditure on health as a significant interaction that affects health performance in Nigeria. Consequently, efforts by the government to ensure