48 resultados para Household ecology
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Strong genetic change over short spatial scales is surprising among marine species with high dispersal potential. Concordant breaks among several species signals a role for geographic barriers to dispersal. Along the coast of California, such breaks have not been seen across the biogeographic barrier of Point Conception, but other potential geographic boundaries have been surveyed less often.;We tested for strong-population structure in 11 species of Sebastes sampled across two regions containing potential dispersal barriers, and conducted a meta-analysis including four additional species. We show two strong breaks north of Monterey Bay, spanning an oceanographic gradient and an upwelling jet. Moderate genetic structure is just as common in the north as it is in the south, across the biogeographic break at Point Conception. Gene Xow is generally higher among deep-water species, but these conclusions are confounded by phylogeny. Species in the subgenus Sebastosomus have higher structure than those in the subgenus;Pteropodus, despite having larvae with longer pelagic phases. DiVerences in settlement behavior in the face of ocean currents might help explain these diVerences. Across similar species across the same coastal environment, we document a wide variety of patterns in gene Xow, suggesting that interaction of individual species traits such as settlement behavior with environmental factors such as;oceanography can strongly impact population structure
Resumo:
Vaginal practices in sub-Saharan Africa may increase HIV transmission and have important implications for development of microbicides and future HIV prevention technologies. It remains unclear which women undertake vaginal practices and what factors predict prevalence, practice type and choice of products. Using cross-sectional data from mixed research methods, we identify factors associated with vaginal practices among women in KwaZulu-Natal, South Africa. Data were gathered through focus group discussions, in-depth and key-informant interviews, followed by a province-wide, multi-stage cluster household survey, using structured questionnaires in face-to-face interviews with 867 women. This paper details six types of vaginal practices, which--despite their individual distinctiveness and diverse motivations--may be clustered into two broad groups: those undertaken for purposes of 'hygiene' (genital washing, douching and application) and those for 'sexual motivations' (application, insertion, ingestion and incisions). Multivariate analysis found significant associations between 'hygiene' practices and media access, religiosity and transactional sex. 'Sexual' practices were associated with partner concurrency, religiosity and use of injectable hormonal contraceptives. Future interventions relating to vaginal practices as well as microbicides need to reflect this characterisation of practices as sexual- and/or hygiene-related.
Resumo:
Background: Women worldwide use various vaginal practices to clean or modify their vulva and vagina. Additional population-level information is needed on prevalence and motivations for these practices, characteristics of users, and their adverse effects. Methods: This was a household survey using multistage cluster sampling in Tete, Mozambique; KwaZulu-Natal, South Africa; Yogyakarta, Indonesia; and Chonburi, Thailand. In 2006–2007, vaginal practices and their motivations were examined using structured interviews with women 18–60 years of age (n=3610). Results: Prevalence, frequency, and motivations varied markedly. Two thirds of women in Yogyakarta and Chonburi reported one or more practices. In Yogyakarta, nearly half ingest substances with vaginal effects, and in Chonburi, external washing and application predominate. In Tete, half reported three or four current practices, and a quarter reported five or more practices. Labial elongation was near universal, and 92% of those surveyed cleanse internally. Two third's in KwaZulu-Natal practiced internal cleansing. Insertion of traditional solid products was rare in Chonburi and Yogyakarta, but one tenth of women in KwaZulu-Natal and nearly two thirds of women in Tete do so. Multivariate analysis of the most common practice in each site showed these were more common among less educated women in Africa and young urban women in Asia. Explicit sexual motivations were frequent in KwaZulu-Natal and Tete, intended for pleasure and maintaining partner commitment. Practices in Chonburi and Yogyakarta were largely motivated by femininity and health. Genital irritation was common at African sites. Conclusions: Vaginal practices are not as rare, exotic, or benign as sometimes assumed. Limited evidence of their biomedical consequences remains a concern; further investigation of their safety and sexual health implications is warranted.
Resumo:
The spectacular diversity in sexually selected traits among animal taxa has inspired the hypothesis that divergent sexual selection can drive speciation. Unfortunately, speciation biologists often consider sexual selection in isolation from natural selection, even though sexually selected traits evolve in an ecological context: both preferences and traits are often subject to natural selection. Conversely, while behavioural ecologists may address ecological effects on sexual communication, they rarely measure the consequences for population divergence. Herein, we review the empirical literature addressing the mechanisms by which natural selection and sexual selection can interact during speciation. We find that convincing evidence for any of these scenarios is thin. However, the available data strongly support various diversifying effects that emerge from interactions between sexual selection and environmental heterogeneity. We suggest that evaluating the evolutionary consequences of these effects requires a better integration of behavioural, ecological and evolutionary research.
Resumo:
Studies about transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in hospitals and households are scarce.