Environmental and Climatic Determinants of Molecular Diversity and Genetic Population Structure in a Coenagrionid Damselfly

Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean FST = 0.06, Dest = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. FST-and Dest-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats

Predictors of condom use and refusal among the population of Free State province in South Africa

<p>Abstract</p> <p>Background</p> <p>This study investigated the extent and predictors of condom use and condom refusal in the Free State province in South Africa.</p> <p>Methods</p> <p>Through a household survey conducted in the Free Sate province of South Africa, 5,837 adults were interviewed. Univariate and multivariate survey logistic regressions and classification trees (CT) were used for analysing two response variables ‘ever used condom’ and ‘ever refused condom’.</p> <p>Results</p> <p>Eighty-three per cent of the respondents had ever used condoms, of which 38% always used them; 61% used them during the last sexual intercourse and 9% had ever refused to use them. The univariate logistic regression models and CT analysis indicated that a strong predictor of condom use was its perceived need. In the CT analysis, this variable was followed in importance by ‘knowledge of correct use of condom’, condom availability, young age, being single and higher education. ‘Perceived need’ for condoms did not remain significant in the multivariate analysis after controlling for other variables. The strongest predictor of condom refusal, as shown by the CT, was shame associated with condoms followed by the presence of sexual risk behaviour, knowing one’s HIV status, older age and lacking knowledge of condoms (i.e., ability to prevent sexually transmitted diseases and pregnancy, availability, correct and consistent use and existence of female condoms). In the multivariate logistic regression, age was not significant for condom refusal while affordability and perceived need were additional significant variables.</p> <p>Conclusions</p> <p>The use of complementary modelling techniques such as CT in addition to logistic regressions adds to a better understanding of condom use and refusal. Further improvement in correct and consistent use of condoms will require targeted interventions. In addition to existing social marketing campaigns, tailored approaches should focus on establishing the perceived need for condom-use and improving skills for correct use. They should also incorporate interventions to reduce the shame associated with condoms and individual counselling of those likely to refuse condoms.</p

Impact of Intimate Partner Forced Sex on HIV Risk Factors in Physically Abused African American and African Caribbean Women

We examined associations between intimate partner forced sex (IPFS) and HIV sexual risk behaviors among physically abused Black women. Women aged 18-55 in intimate relationships were interviewed in health clinics in Baltimore, MD and St. Thomas and St. Croix, US Virgin Islands (USVI). Of 426 physically abused women, 38% experienced IPFS; (Baltimore = 44 and USVI = 116). USVI women experiencing IPFS were more likely to have 3+ past-year sex partners (AOR 2.06, 95% CI 1.03-4.14), casual sex partners (AOR 2.71, 95% CI 1.42-5.17), and concurrent sex partners (AOR 1.94, 95% CI 1.01-3.73) compared to their counterparts. Baltimore women reporting IPFS were more likely to have exchanged sex (AOR 3.57, 95% CI 1.19-10.75). Women experiencing IPFS were more likely to report their abuser having other sexual partners in Baltimore (AOR 3.30, 95% CI 1.22-8.88) and USVI (AOR 2.03, 95% CI 1.20-3.44). Clinicians should consider the influence of IPFS on individual and partnership HIV sexual risk behaviors

Alcohol Consumption as a Barrier to Prior HIV Testing in a Population-Based Study in Rural Uganda

Early receipt of HIV care and ART is essential for improving treatment outcomes, but is dependent first upon HIV testing. Heavy alcohol consumption is common in sub-Saharan Africa, a barrier to ART adherence, and a potential barrier to HIV care. We conducted a population-based study of 2,516 adults in southwestern Uganda from November-December 2007, and estimated the relative risk of having never been tested for HIV using sex-stratified Poisson models. More men (63.9%) than women (56.9%) had never been tested. In multivariable analysis, compared to women who had not consumed alcohol for at least 5 years, women who were current heavy drinkers and women who last drank alcohol 1-5 years prior, were more likely to have never been tested. Alcohol use was not associated with prior HIV testing among men. HIV testing strategies may thus need to specifically target women who drink alcohol