67 research outputs found

    Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models

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    Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs

    Knowledge, attitudes and practices of nurses and doctors about the vertical transmission of hepatitis B

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    OBJECTIVE: to identify knowledge, attitudes and practices of physicians and nurses of the Family Health Strategy and a maternity hospital unit about vertical transmission of hepatitis B. METHOD: a cross-sectional study with a self-administered questionnaire applied to professionals. The data were analyzed according to professional category and site of action, whose differences were tested by χ2 and significance <5%. RESULTS: professionals recognize viral hepatitis as a disease of compulsory notification; however, not everyone knows its mechanisms of transmission. A large portion of professionals requested serological tests, specifying the marker, especially physicians. The majority of family health nurses did not indicate hepatitis B vaccine for pregnant women, although they knew the immunization schedule. The majority of physicians on the maternity unit had proper knowledge about prevention of vertical transmission. CONCLUSION: the differences in the knowledge, attitudes and practices about vertical transmission of hepatitis B revealed that the population is at risk, since not all the professionals involved know or properly perform control strategies for vertical transmission of hepatitis B. Nurses dominated vaccination aspects and physicians dominated aspects related to the management of cases with positive serology

    Selecting the most adequate bedding material for broiler production in Brazil

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    Broiler chicken production is widely dispersed across the globe, and one important issue for growers is the selection of adequate bedding material, as the availability and price of substrates varies among countries and regions within a same country. This study aimed at applying a multiple criteria analysis approach for the selection of the most appropriate bedding material for broiler production. Based on field research data and growers' experience, the most desirable characteristics of a litter material were chosen as the main criteria. The selected materials were wood shavings, rice husks, chopped Napier grass (Pennisetum pupureum), 50% sugar cane bagasse (Saccharum L.) plus 50% wood shavings, 50% sugar cane bagasse (Saccharum L.) plus 50% rice husks, and pure sugar cane bagasse (Saccharum L.). The analytical hierarchy process (AHP) was applied for selecting the most suitable bedding material. Validation was performed using data from previous studies carried out in central-western Brazil on the effects of different types of bedding material on broiler carcass quality. Considering the selected criteria, several bedding materials were tested and ranked, and the results showed that wood-shavings litter was the best option (weight = 0.28), followed by rice husks (weight = 0.24). All other tested alternatives presented lower scores and were, therefore, not considered for use. The AHP approach was found to be an efficient tool to select the most appropriate litter material under specific scenarios

    Insatisfação corporal em gestantes: uma revisão integrativa da literatura

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    Resumo A imagem corporal de gestantes deve ser alvo de atenção por parte dos profissionais, tendo em vista a promoção da saúde materna infantil. O objetivo da presente revisão integrativa foi analisar a literatura sobre imagem e insatisfação corporal em gestantes. Foram buscados artigos nas bases de dados Scopus, PubMed, BVS e PsycINFO utilizando o cruzamento de “pregnancy” com as palavras-chave: “body image” e “body dissatisfaction”. Após a adoção dos critérios de inclusão e exclusão foram analisados 40 estudos. Estes apontam dados inconclusivos quanto à insatisfação corporal durante a gestação. Presença de sintomas depressivos, baixa autoestima, atitude alimentar inadequada e ganho de peso fora dos limites recomendados têm sido associados a uma imagem corporal negativa. Contradições nos achados podem estar relacionados às diferenças nos instrumentos utilizados para mensurar a imagem corporal. Pelo possível impacto de uma imagem corporal negativa durante a gestação na saúde materna e infantil, são recomendadas novas investigações, em especial o desenvolvimento de um instrumento avaliativo de imagem corporal específico para gestantes
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