982 resultados para região neotropical


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In the semiarid region of northeastern of Brazil, the reservoirs are vulnerable to water level seasonal fluctuations, they re related to the hydrological cycle. The rain periods are irregular and there are long periods of drought that increases eutrophication process. That happens because of the water level s reduction and nutrient concentration. The Boqueirao, located in northeastern Brazil , is a mesotrophic reservoir. The reservoir is naturally susceptible to deterioration of water quality. This happens because of the potential diffuse sources arising from the use and occupation of the basin, associated with shallow soil caatinga biome and highly vulnerable to erosion. This study aimed to analyze the influence of the use and occupation of the area around and the water quality of the watershed. A study of the area around the Boqueirão was performed, taking the potentially polluting activities. Limnological variables were monitored monthly in 3 points of the reservoir to assess the water quality. Was evidenced an event of prolonged drought, with rainfall below the historical average for the year of study. By the index of water quality, the watershed was classified as " good " during the whole year of 2012. According to the trophic index adopted the reservoir is characterized as mesotrophic. The main anthropogenic impacts identified in the soil were arboreal selective logging, mining, diffuse contribution of residues from agricultural and livestock activities. The lack of precipitation and the degradation of the surrounding area, affect negatively the water quality, requiring immediate control to prevent degradation of the watershed . Although there wasn t a majority polluting activity in the region. The total of several impacting activities, the high susceptibility of the soil and the selective clearing of caatinga vegetation can accelerate the natural process of eutrophication in the water body

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The aquatic ecosystems can play a role as carbon-dioxide-source or carbon-dioxide-sink systems due to the high predominance of heterotrophic or autotrophic metabolism. The primary production can strongly affect the carbon balance (CO2) through the consumption of carbon dioxide in the photosynthesis, especially in eutrophic environment, acting as a carbon sink. The present study tested the hypothesis that the eutrophic reservoirs in tropical semi-arid region are carbon dioxide-sink systems due to the high primary productivity presented in these systems. Five Brazilian reservoirs from the semi-arid in the northeast region were monitored monthly during four years (2010 to 2013) with a prolonged drought event identified during the study. The results showed an increasing level of eutrophication over the period of prolonged drought, with the predominance of autotrophy. Significant negative correlations were observed between the partial pressure of CO2 (pCO2) (p<0,001) and chlorophyll-a in the Boqueirão, Passagem das Traíras, Dourado and Gargalheiras reservoirs, showing a pattern of the carbon dioxide-sink systems. However, this pattern was not found in Cruzeta reservoir. In summary, in the tropical semi-arid region, hydrological and morphometric variables can lead to different behaviors of the water-supply reservoirs on the carbon metabolism. The eutrophic reservoirs evaluated showed a negative relationship between pCO2 and Chl-a, which suggests that these water bodies show an autotrophic metabolism and behave as carbon dioxide- sink systems

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Gochnatia polymorpha (Less.) Cabrera is a widespread tree species found in different physiognomies of neotropical savanna (cerrado) formations of south-eastern Brazil. The present study describes some leaf anatomical characteristics of this species as a function of the time of leaf flush, during dry or wet seasons. This species presents anatomical plasticity in the cuticle, palisade parenchyma and abaxial epidermis as well as in stomatal size and stomatal and trichome density, which are leaf structures linked with water-status control. Leaf structure changed to suit the particular environmental conditions during dry and wet seasons. The production of different wet-and dry-season leaf types in G. polymorpha could be a response to drought and an adaptation to environmental constraints in the cerrado.

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Seasonal variation of abundance of Ecballocystis pulvinata Bohlin in a stream of central-southern region of Parana State. The temporal dynamics of E. pulvinata and its relation to abiotic variables were evaluated monthly during January to December 2007 in a stream located in the central-southern part of Parana State (25 degrees 11'16 '' S - 51 degrees 021'25 '' W). The abundance of the population in terms of percentage cover was obtained by means of the quadrat technique and the following stream water variables were measured: current velocity, irradiance, depth, substrate type, temperature, oxygen saturation, conductivity, pH and turbidity. The abundance of E. pulvinata was considered high (X = 26.7%), with more development (22-46%) during autumn/winter. The low values (0-0.08) of niche width and the few associations with environmental variables shows that the population evaluated is a generalist with regards to the environment in which it occurs. Factors most strictly related were the water flow and the particle size of the substrate, which positively correlated to the seasonal pattern of the population investigated.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This work has as objective to describe mathematical knowledge used as tools in the manufacture and marketing of tiles of red ceramic by potters of the Currais Novos village/ RN, located 250 km from the capital of Rio Grande do Norte. For us to reach our objective, we rely on conceptions ambrosianas of Ethnomatematics, besides of the qualitative research in an ethnographic approach. In the empirical part of the research, that went it accomplishes in the period from 2009 to 2012 in the Currais Novos Village, we support the following tools for data collection, semi-structured interviews, field diary, photographs, audio recordings and participant observations. In the analysis of the collected data, we can conclude that there are mathematical knowledge in the management of manufacture and marketing of tiles, often different from the academic mathematics, mainly in the wood cube, on cube of the clays, in the handler with the measures time, the count method , in the arrangement of tiles, in the preparation of the ceramic mass and sale of tiles. Theses knowledge were described and analyzed in the light of the theoretical Ethnomatematics, also supported in official documents, such as Parameters Nacional Curriculares. The analyzes of these knowledge generated subsidies for elaboration of an educational product - a proposal of didactic sequence destined to the Teaching of Mathematics in Elementary and Middle levels for the community schools and region, this proposal is in the Appendix to this work

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One of the main drawbacks of the GPS accuracy for L1 users is the error due to ionosphere. This error depends on the total electron content presents in the ionosphere, as well as of the carrier frequency. Some models have been developed to correct GPS observables of the systematic error due to the ionosphere. The model more known and used is the Klobuchar model, which corrected 50-60% of the ionospheric error approximately. Alternatively, IGS (International GNSS Service) also has developed a model called Global Ionospheric Map (GIM). These maps, in format IONEX, are available in the site of the IGS, and one of the applications of them is to correct the GPS observables of the error due to ionosphere. This work aims at evaluating the quality of GPS point positioning using the IGS ionospheric model in the southerm region of Brazil. Tests carried out had shown an average improvement in the horizontal and vertical determination of 44% and 77%, respectively, when GIM is used in the point positioning.

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INTRODUÇÃO: A mortalidade infantil em Presidente Prudente, SP (Brasil), foi estudada no período de 1990 a 1992, a partir de aplicação de métodos para obtenção de diagnóstico coletivo que orientassem a identificação e escolha de estratégias de controle de problemas locais. MATERIAL E MÉTODO: Foram utilizadas declarações de óbito colhidas no cartório, cujos dados originais foram corrigidos por meio de pesquisa documental nos serviços de saúde e entrevistas domiciliares. Para estudar variáveis como idade materna e peso ao nascer foram utilizados os dados do Sistema de Informações sobre Nascidos Vivos (SINASC). A qualidade dos dados originais das declarações de óbitos foi inicialmente analisada pela quantidade de informações, sensibilidade, especificidade e valor de Kappa. RESULTADO: A sensibilidade global para a causa básica de óbito foi 78,84% e Kappa igual a 71,32 para o total de causas. Ocorreram 189 óbitos, sendo 66,15% no período neonatal (41,28% durante o primeiro dia de vida) e 33,85% no infantil tardio. O peso ao nascer de 58,28% dos óbitos foi menor que 2.500g. As causas básicas de óbito foram estudadas segundo a possibilidade de serem prevenidas (método desenvolvido por Erica Taucher) por grupos de causas reduzidas utilizadas no International Collaborative Effort (ICE), causas múltiplas e distribuição geográfica. Observou-se que nos óbitos ocorridos até 27 dias, 22,23% poderiam ser evitados por adequada atenção ao parto, 20,64% seriam redutíveis por diagnóstico e tratamento precoce, 13,75% por bom controle da gravidez e apenas 7,94% não evitáveis. Das mortes ocorridas no período infantil tardio, 12,17% foram classificadas como outras preveníveis e 4,23% foram consideradas não evitáveis. Segundo os grupos do ICE, 58,74% faleceram por imaturidade ou asfixias; 19,58% por infecções e, 12,17%, por anomalias congênitas. CONCLUSÃO: Os resultados sugerem prioridade para assistência obstétrica no trabalho de parto e atenção pediátrica por baixo peso ao nascer, entre outras. A análise por causas múltiplas mostra que 76,05% dos óbitos têm as causas básicas relacionadas a causas perinatais e confirma a relação entre as deficiências de peso e as complicações respiratórias do recém-nascido. As complicações maternas também relacionaram-se com o baixo peso. Identificaram-se grandes diferenças no coeficiente de mortalidade infantil entre as áreas da zona urbana não somente restritas aos valores, como também ao tipo de doenças responsáveis pela ocorrência do óbito. Conclui-se haver vantagem no uso associado das quatro técnicas que são complementares, tanto para estudo, como para planejamento de ações dirigidas à prevenção da mortalidade infantil.

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The aim of this study is to analyze the effect of migration on the income differential between northeastern migrants and nonmigrants and there by verify that the immigrants make up a group or not positively selected. The assumption that will be tested is that the presence of these immigrants affects income inequality in the region receptor, which may explain part of the high-stopping inequality in the Brazilian Northeast. The study is based on the literature selectivity migration introduced by Roy (1951), Borjas (1987) and Chiswick (1999). Does the estimated wage equation Mincer (1974) through the method of OLS, using information from the microdata sample of the 2010 Census, the Brazilian Institute of Geography and Statistics (IBGE). The results which correspond to the comparison of socioeconomic profile, showed that immigrants are more qualified and, on average, better paid than non-migrants. With the estimation of the model, it was found that, keeping all other variables constant, the income that immigrants earn is 14.43% higher than that of non-migrants. Thus, there was existence of positive selectivity in migration directed to the Northeast

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This dissertation seeks to reflect on the accessibility of the governmental program Minha Casa Minha Vida, track 1, which comprehends people who made 0 to 3 minimum wages within the metropolitan region of Natal RN between the years of 2009 and 2012. The research covers the municipalities benefited by the program: Ceará-Mirim, Extremoz, Macaíba, Monte Alegre, Natal, Nísia Floresta, Parnamirim and São Gonçalo do Amarante. We have investigated the extensions of PMCMV on the context of the access to the city, debating some concepts attached to the capitalist mode of production such as residential segregation and peripherization. We have aimed to identify the accessibility conditions in the new housing complexes from three primal categories, namely, the localization of the complexes, the disponibility of public equipments, services, leisure and cultural properties on the neighborhood and the offer of public transport. Our theorical references are based on the ideas of the british geographer David Harvey on his work Social Justice and the City , from 1980. Harvey s studies made us debate on the locational choice for the social-matter habitation, and also let us discuss the price to accessibility on these new programs and its implications on the income of those who are benefited by them, specially because this is about a low-income population. To the achievement of these objectives, we made use of case study, including desk research, photographic documentation, records of field observations and informal conversations with locals, composing a qualitative study. In light of what has been researched and considering the guiding research questions, we reflect on aspects of the program that can greatly influence the processes of residential segregation and housing periphery of the lowincome population from the precarious conditions of accessibility to the referred population