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Analyzing Community Responses to HIV and AIDS : Operational Framework and TypologyThis paper presents a framework for analyzing the community response to HIV and AIDS. On the basis of a review of the literature, six criteria are proposed for characterizing such community responses: (1) the types of organizations and structures implementing the response, (2) the types of activities or services implemented and the beneficiaries of these, (3) the actors involved in and driving community responses, (4) the contextual factors that influence community responses, (5) the extent of community involvement in the response, and (6) the extent to which community responses involve wider partnerships and collaboration.
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Interspecific Differences in Diet between Introduced Red-eared Sliders and Native Turtles in ChinaAlthough the alien Red-eared slider (Trachemys scripta elegans) is generally argued as an invasive species that competes with native turtles, the field evidence on its diet is controversial. Field studies conducted at the Gutian Nature Reserve of Guangdong and along the Wanquan River in Hainan, China show that T.s. elegans is an opportunitic omnivore, consuming a wide variety of food items. Consumption varies throughout its range; more plant material is consumed in Guangdong, compared to a more carnivorous diet in Hainan; and juveniles are also found to have a more carnivorous diet than adults. This implies a high adaptability to new environment. Sympatric native Mauremys sinensis shows a more herbivorous diet and a narrower niche breadth (0.0260) in Hainan, plus a low niche overlap (0.3048) with T.s. elegans, providing a potential empty niche for the invasive T.s. elegans. Red-eared slider is also known to consume large quantities of native prey species to disrupt the ecological balance. It is imperative to understand the invasive nature of this species and the mechanisms by which it affects native ecology.
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Invasion possibility and potential effects of Rhus typhina on beijing municipalityRhus typhina, an alien species introduced from North America, was identified as a main afforestation species in Beijing municipality. However, its invasiveness is still at odds. To clarify this problem, we applied the North American Screening System and the Australian Screening System to preliminarily predict its invasion possibility. Both screening systems gave the same recommendation to "reject". The geographical distribution was surveyed, with the population features of R. typhina against the native plant communities being assessed. With anthropogenic assistance, R. typhina has been scattered on almost all habitats from downtown to mountains, including roadsides, farmlands and protected areas. As a clonal shrub, R. typhina possessed a high spreading rate, varying from 6.3 m/3 years at sterile habitats to 6.7 m/3 years at fertile ones. Significantly lower species richness, individual density and diversity were observed in the R. typhina community than those of the native Vitex negundo Linn.var. heterophylla (Franch.) Rehd. community at both sterile and fertile habitats. Continual wide plantation of R. typhina may further foster its population expansion, which helps the species to overcome spatial isolation. The fact that each root fragment can develop into a new individual makes R. typhina very difficult to be eradicated once established. From a biological point of view, we believe that R. typhina is a plant invader in Beijing. We therefore suggest the government should remove the name of R. typhina from the main tree species list in afforesting Beijing.