1,667 research outputs found

    Effects of Pleistocene climate changes on species ranges and evolutionary processes in the Neotropical Atlantic Forest

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    The effects of global glaciations on the distribution of organisms is an essential element of many diversification models. However, the empirical evidence supporting this idea is mixed, in particular with respect to explaining tropical forest evolution. In the present study, we evaluated the impacts of range shifts associated with Pleistocene global glacial cycles on the evolution of tropical forests. In particular, we tested the predictions: (1) that population genetic structure increases with fragmentation variation between the present and the Last Glacial Maximum (LGM) and also (2) with geographical range instability; and (3) that genetic diversity increases with range stability and (4) decreases with fragmentation variation between periods. To address our predictions, we studied population genetic structures and modelled present and past distributions of 15 Atlantic Forest (AF) endemic birds. Afterwards, we evaluated the relationship of population genetic parameters with metrics of species range shifts between the present and the LGM. We found that geographical ranges of AF birds changed in concert with Pleistocene glacial cycles but, unexpectedly, our findings suggest the novel idea that ranges during glacial maxima were slightly larger on average, as well as equally fragmented and displaced from the interglacial ranges. Our findings suggest that range shifts over the late Pleistocene impacted on the diversification of forest organisms, although they did not show that those range shifts had a strong effect. We found that a combination of fragmentation variation across time, small current range size, and range stability increased population genetic structure. However, neither fragmentation, nor range stability affected genetic diversity. Our study showed that evolutionary responses to range shifts across AF birds have a high variance, which could explain the mixed support given by single-species studies to the action of Pleistocene range shifts on population evolution.Fil: Cabanne, Gustavo Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Calderón, Pablo Luciano Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Trujillo Arias, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Flores, Pamela. Universidad Nacional de General Sarmiento; ArgentinaFil: Pessoa, Rodrigo. Universidade Estadual de Montes Claros; BrasilFil: d'Horta, Fernando M.. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Miyaki, Cristina Y.. Universidade de Sao Paulo; Brasi

    Core Components for Infection Prevention and Control Programs: A World Health Organization Network Report

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    Under the leadership of the World Health Organization (WHO), the core components necessary for national and local infection prevention and control programs are identified. These components were determined by a network of international experts who are representatives from WHO regional offices and relevant WHO programs. The respective roles of the national authorities and the local healthcare facilities are delineate

    Scale of results in research groups

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    Purpose: the aim of this paper is to develop a scale to measure results in research groups (RG). Originality/value: the study is innovative in developing a scale for verifying results in Brazilian RG. Its main contribution is data collection from an evaluation made by leaders regarding results that RG’ produced as a whole (meso or organizational level), going further than individual indices of academic productivity. Design/methodology/approach: the scale was developed based on: 1) literature review of empirical papers published between 2005 and 2015 regarding results in RG; and 2) analysis of data (audio recordings, interview transcriptions, field reports) previously collected from RG members, regarding achieved results and re-evaluation of preliminary instruments developed by RG. In total, 387 RG leaders answered the survey after semantic and theoretical analysis by experts and a pre-test. Findings: exploratory factor analysis revealed three factors in the results (Distal Results of External Repercussion, Proximal Research Results and Tangible Research Results), with a total variance of 51.9% explained and reliability indices of α = 0.927, α = 0.872 and α = 0.624, respectively

    "A Very Original Dinner"

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