9 research outputs found

    Potential impacts of climate change on biogeochemical functioning of Cerrado ecosystems

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    The Cerrado Domain comprises one of the most diverse savannas in the world and is undergoing a rapid loss of habitats due to changes in fire regimes and intense conversion of native areas to agriculture. We reviewed data on the biogeochemical functioning of Cerrado ecosystems and evaluated the potential impacts of regional climate changes. Variation in temperature extremes and in total amount of rainfall and altitude throughout the Cerrado determines marked differences in the composition of species. Cerrado ecosystems are controlled by interactions between water and nutrient availability. In general, nutrient cycles (N, P and base cations) are very conservative, while litter, microbial and plant biomass are important stocks. In terms of C cycling, root systems and especially the soil organic matter are the most important stocks. Typical cerrado ecosystems function as C sinks on an annual basis, although they work as source of C to the atmosphere close to the end of the dry season. Fire is an important factor altering stocks and fluxes of C and nutrients. Predicted changes in temperature, amount and distribution of precipitation vary according to Cerrado sub-regions with more marked changes in the northeastern part of the domain. Higher temperatures, decreases in rainfall with increase in length of the dry season could shift net ecosystem exchanges from C sink to source of C and might intensify burning, reducing nutrient stocks. Interactions between the heterogeneity in the composition and abundance of biological communities throughout the Cerrado Domain and current and future changes in land use make it difficult to project the impacts of future climate scenarios at different temporal and spatial scales and new modeling approaches are needed

    A contribuição dos estudos transculturais dos países latino-americanos e caribenhos para a revisão da CID-10: resultados preliminares The contribution of Latin American and Caribbean countries on culture bound syndromes studies for the ICD-10 revision: key findings from a working in progress

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    OBJETIVO: Esta revisão visa identificar as evidências dos estudos de países da América Latina e do Caribe para a inclusão das síndromes transculturais na versão da Classificação Internacional de Doenças para sua 11ª Edição. MÉTODO: Os estudos foram identificados nas bases do Medline, LILACS e EMBASE, no período de 1992 a 2008, e classificados segundo o tipo de estudo, tipo de transtorno, país e número de publicações por ano. RESULTADOS: Foram selecionadas e classificadas 163 publicações: 33 no Medline, 90 no EMBASE e 40 no LILACS. A percentagem das síndromes transculturais ("culture bound-syndrome") correspondeu a 9% no Medline, 12% no EMBASE e 2,5% no LILACS. Dos 15 estudos sobre síndromes transculturais, dois eram sobre "nervios e ataque de nervios", dois sobre "susto", quatro sobre a relação entre crenças religiosas, "feitiçaria", transe e apresentação dos transtornos mentais, um sobre proposta de uma nova categoria diagnóstica, três artigos teóricos e três sobre psicopatoplastia dos transtornos mentais. CONCLUSÃO: A escassez de estudos sobre síndromes transculturais pode ter ocorrido pela dificuldade em rastrear os estudos por problema de indexação das publicações, falta de interesse em publicar tais estudos em periódicos indexados e a dificuldade de acesso às publicações. Dentre os estudos identificados, não há uma evidência clara que aponte quais modificações são necessárias nas classificações diagnósticas atuais.<br>OBJECTIVE: This review aims to verify the scientific evidences for the inclusion of culture bound syndromes in the International Classification of Diseases towards its 11th edition based on studies from Latin American and Caribbean countries. METHOD: Studies were identified in Medline, LILACS and EMBASE databases for the period between 1992 and 2008, and then classified according to the type of study, to the mental disorder, country and number of publications per year. RESULTS: 163 studies were selected and classified: 33 in MedlLne, 90 in EMBASE e 40 in LILACS. The percentage of culture bound-syndrome corresponded to 9% in Medline, 12% in EMBASE e 2.5% in LILACS. Among fifteen studies on cultural bound syndromes, two were about "nervios and ataque de nervios", two about "susto", four about the relationship between religion beliefs, witchery, trance and mental disorders, one with a proposal for new diagnostic category, three about theoretic issues and three about the pathoplasty of mental disorders. CONCLUSION: The scarcity of studies on culture bound syndromes might be due to the indexation problems hindering the screening of studies; lack of interest on publishing such studies in indexed journals (publication bias) and due to difficulty to access them. There is no robust evidence identified among cross-cultural studies to recommend changes for International Classification of Diseases-11th edition
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