Search results for " africa"

Data from: Fine-scale spatial genetic dynamics over the life-cycle of the tropical tree Prunus africana

2014

Studying fine-scale spatial genetic patterns across life stages is a powerful approach to identify ecological processes acting within tree populations. We investigated spatial genetic dynamics across five life stages in the insect-pollinated and vertebrate-dispersed tropical tree Prunus africana in Kakamega Forest, Kenya. Using six highly polymorphic microsatellite loci, we assessed genetic diversity and spatial genetic structure (SGS) from seed rain and seedlings, and different sapling stages to adult trees. We found significant SGS in all stages, potentially caused by limited seed dispersal and high recruitment rates in areas with high light availability. SGS decreased from seed and early…

Ethnic differences in serum lipoproteins and their determinants in South African women

2010

Global diversity in the TAS2R38 bitter taste receptor: revisiting a classic evolutionary PROPosal

2016

AbstractThe ability to taste phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) is a polymorphic trait mediated by the TAS2R38 bitter taste receptor gene. It has long been hypothesized that global genetic diversity at this locus evolved under pervasive pressures from balancing natural selection. However, recent high-resolution population genetic studies of TAS2Rs suggest that demographic events have played a critical role in the evolution of these genes. We here utilized the largest TAS2R38 database yet analyzed, consisting of 5,589 individuals from 105 populations, to examine natural selection, haplotype frequencies and linkage disequilibrium to estimate the effects of both selectio…

Consequences of the disorders socio-policies on the Central African education system of 1991 to the year 2001: situation of primary education teaching

2006

This work deals about the impacts both on supply and demand of education emerging from socio-political instability and trouble, the Sub Saharan geographical context. The targeted goal is to present a comparative analysis which indicates that countries could attain objective in the development of education if the context for civil peace appear satisfied. Then, by a historical and socio-political step, the study in the evolution of the school since its creation in the Central Africa case shows that multiple factors impacted within time duration the development of education. Lastly, the analysis of the consequences of the disorders encountered in the since the beginning of the Nineties reveals…

The Libyan Collections in FI (Herbarium Centrale Italicum and Webb Herbarium) and Studies on the Libyan Flora by R. Pampanini – Part 2

2016

This work is the continuation of Part 1, published in 2015, and comprises the reconstruction of the original collections of new taxa described by R. Pampanini and other botanists and, where possible, typification of the new names and taxonomical updating. The material studied for the most part concerns Libyan specimens held in the FI and FI-W herbaria but in some case also K, LD, MPU, P, PAD, PAL, ULT. Other material, which Pampanini studied in Florence was subsequently conserved in other herbaria. Specimens belonging to 21 families have been examined, from the Najadaceae to Zygophyllaceae. As well as typification, bibliographical data have been provided for those already typified. In this …

Ethnic differences in serum lipoproteins and their determinants in South African women.

2010

The objective of the study was to characterize ethnic differences in lipid levels and low-density lipoprotein (LDL) particle size and subclasses in black and white South African women and to explore the associations with insulin sensitivity (S(I)), body composition, and lifestyle factors. Fasting serum lipids and LDL size and subclasses, body composition (dual-energy x-ray absorptiometry), and S(I) (frequently sampled intravenous glucose tolerance test) were measured in normal-weight (body mass index25 kg/m(2)) black (n = 15) and white (n = 15), and obese (body mass index30 kg/m(2)) black (n = 13) and white (n = 13) women. Normal-weight and obese black women had lower triglycerides (0.59 +/…

Schistosoma haematobium Infection and CD4+ T-cell levels: A cross-sectional study of young South African women

2015

Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated the association between low CD4 cell counts in HIV positive women and the number of excreted schistosome eggs in urine. Sixteen percent were HIV positive and 31% had signs of urogenital schistosomiasis…

Reproductive health problems in rural South African young women: risk behaviour and risk factors

2018

Background South African young women continue to be vulnerable, with high prevalence of teenage pregnancy, HIV, sexually transmitted infections (STIs) and female genital schistosomiasis (FGS). This study seeks to examine the underlying factors that may be associated with these four adverse reproductive health outcomes. Methods In a cross-sectional study of 1413 sexually active of young women, we explored these four adverse reproductive health outcomes by considering socio-demographic factors, socio-economic factors, sexual risk behaviour, substance abuse and knowledge about reproductive health by using a questionnaire. Consenting participants were asked about previous pregnancies and were t…

Genome-Wide Association Studies of the PR Interval in African Americans.

2011

The PR interval on the electrocardiogram reflects atrial and atrioventricular nodal conduction time. The PR interval is heritable, provides important information about arrhythmia risk, and has been suggested to differ among human races. Genome-wide association (GWA) studies have identified common genetic determinants of the PR interval in individuals of European and Asian ancestry, but there is a general paucity of GWA studies in individuals of African ancestry. We performed GWA studies in African American individuals from four cohorts (n = 6,247) to identify genetic variants associated with PR interval duration. Genotyping was performed using the Affymetrix 6.0 microarray. Imputation was p…

Genome-wide and gene-centric analyses of circulating myeloperoxidase levels in the charge and care consortia

2013

Increased systemic levels of myeloperoxidase (MPO) are associated with the risk of coronary artery disease (CAD). To identify the genetic factors that are associated with circulating MPO levels, we carried out a genome-wide association study (GWAS) and a gene-centric analysis in subjects of European ancestry and African Americans (AAs). A locus on chromosome 1q31.1 containing the complement factor H (CFH) gene was strongly associated with serum MPO levels in 9305 subjects of European ancestry (lead SNP rs800292; P = 4.89 × 10(-41)) and in 1690 AA subjects (rs505102; P = 1.05 × 10(-8)). Gene-centric analyses in 8335 subjects of European ancestry additionally identified two rare M…