81 resultados para large geographical area

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Background: Vampire bats are important rabies virus vectors, causing critical problems in both the livestock industry and public health sector in Latin America. In order to assess the epidemiological characteristics of vampire bat-transmitted rabies, the authors conducted phylogenetic and geographical analyses using sequence data of a large number of cattle rabies isolates collected from a wide geographical area in Brazil.Methods: Partial nucleoprotein genes of rabies viruses isolated from 666 cattle and 18 vampire bats between 1987 and 2006 were sequenced and used for phylogenetic analysis. The genetic variants were plotted on topographical maps of Brazil.Results: In this study, 593 samples consisting of 24 genetic variants were analyzed. Regional localization of variants was observed, with the distribution of several variants found to be delimited by mountain ranges which served as geographic boundaries. The geographical distributions of vampire-bat and cattle isolates that were classified as the identical phylogenetic group were found to overlap with high certainty. Most of the samples analyzed in this study were isolated from adjacent areas linked by rivers.Conclusion: This study revealed the existence of several dozen regional variants associated with vampire bats in Brazil, with the distribution patterns of these variants found to be affected by mountain ranges and rivers. These results suggest that epidemiological characteristics of vampire bat-related rabies appear to be associated with the topographical and geographical characteristics of areas where cattle are maintained, and the factors affecting vampire bat ecology.

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Paleogene sediments of this region represent a significant source of water for urban, industrial and agricultural activities. This basin is part of the Southeastern Brazilian Continental Rift, which occupies a large portion of this geographical area. This study aims to present the evolution of the natural Paleogene landscape, through an analysis of its stratigraphic intcrops and underground portions based on the concept of facies and facies associations. A total of nine clastic and separate lithofacies were recognized and grouped into two main facies associations. These data suggest the existence of two depositional interdigitated systems: fluvial braided fans, which were predominant in parts of the northern and central area, and another composed of lacustrine sediments found in its central-south region. The paleogeography herein outlined will help considerably in the detection of new areas for mineral and water resources prospection, as well as in urban planning projects of this region.

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Some Eucalyptus species are widely used as a plantation crop in tropical and subtropical regions. One reason for this is the diversity of end uses, but the main reason is the high level of wood production obtained from commercial plantings. With the advancement of biotechnology it will be possible to expand the geographical area in which eucalypts can be used as commercial plantation crops, especially in regions with current climatic restrictions. Despite the popularity of eucalypts and their increasing range, questions still exist, in both traditional planting areas and in the new regions: Can eucalypts invade areas of native vegetation, causing damage to natural ecosystems biodiversity?The objective of this study it was to assess whether eucalypts can invade native vegetation fragments in proximity to commercial stands, and what factors promote this invasive growth. Thus, three experiments were established in forest fragments located in three different regions of Brazil. Each experiment was composed of 40 plots (1 m(2) each one), 20 plots located at the border between the forest fragment and eucalypts plantation, and 20 plots in the interior of the forest fragments. In each experimental site, the plots were paired by two soil exposure conditions, 10 plots in natural conditions and 10 plots with soil exposure (no plant and no litter). During the rainy season, 2 g of eucalypts seeds were sown in each plot, including Eucalyptus grandis or a hybrid of E. urophylla x E. grandis, the most common commercial eucalypt species planted in the three region. At 15, 30, 45, 90, 180, 270 and 360 days after sowing, we assessed the number of seedlings of eucalypts and the number of seedlings of native species resulting from natural regeneration. Fifteen days after sowing, the greatest number of eucalypts seedlings (37 m(-2)) was observed in the plots with lower luminosity and exposed soil. Also, for native species, it was observed that exposed soil improved natural germination reaching the highest number of 163 seedlings per square meter. Site and soil exposure were the factors that have the greatest influence on seed germination of both eucalypt and native species. However, 270 days after sowing, eucalypt seedlings were not observed at any of the three experimental sites. The result shows the inability of eucalypts to adapt to condition outside of their natural range. However, native species demonstrated their strong capacity for natural regeneration in forest fragments under the same conditions where eucalypts were seeded. (C) 2011 Elsevier B.V. All rights reserved.

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Background and objectives Peritonitis remains as the most frequent cause of peritoneal dialysis (PD) failure, impairing patient's outcome. No large multicenter study has addressed socioeconomic, educational, and geographic issues as peritonitis risk factors in countries with a large geographic area and diverse socioeconomic conditions, such as Brazil.Design, setting, participants, & measurements Incident PD patients recruited from 114 dialysis centers and reporting to BRAZPD, a multicenter observational study, from December 2004 through October 2007 were included. Clinical, dialysis-related, demographic, and socioeconomic variables were analyzed. Patients were followed up until their first peritonitis. Cox proportional model was used to determine independent factors associated with peritonitis.Results In a cumulative follow-up of 2032 patients during 22.026 patient-months, 474 (23.3%) presented a first peritonitis episode. In contrast to earlier findings, PD modality, previous hemodialysis, diabetes, gender, age, and family income were not risk predictors. Factors independently associated with increased hazard risk were lower educational level, non-white race, region where patients live, shorter distance from dialysis center, and lower number of patients per center.Conclusions Educational level and geographic factors as well as race and center size are associated with risk for the first peritonitis, independent of socioeconomic status, PD modality, and comorbidities. Clin J Am Soc Nephrol 6: 1944-1951, 2011. doi: 10.2215/CJN.11431210

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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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O Planejamento Paisagístico do Campus da Faculdade de Ciências Agronômicas da Universidade Estadual Paulista (UNESP) em Botucatu - SP, foi elaborado a partir de um Plano Diretor já existente e considerado o comportamento da paisagem, com edificações e circulações já estabelecidas, dando ênfase ao projeto de ajardinamento do entorno da Central de Salas de Aulas. Os objetivos principais do planejamento visam a proteção do solo, arborização adequada e ajardinamento do encontro dos prédios principais. O traçado proposto é simples, com a finalidade de dar uma escala humana ao Campus, considerando a necessidade dos usuários e de favorecer a utilização de máquinas para manutenção e tratos culturais, em face da pequena disponibilidade de mão-de-obra, sendo mais elaborado somente nos entornos dos prédios principais. A estrutura vegetal é formada de árvores, arbustos, gramados e outras forrações que foram selecionadas por sua rusticidade, resistência, aclimatação ao local e disponibilidade nos Viveiros Experimentais da Faculdade de Ciências Agronômicas-UNESP. Procurou-se utilizar, sempre que possível, espécies nativas

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Significant progress is being made in the photovoltaic energy conversion using organic semiconducting materials. One of the focuses of attention is the morphology of the donor-acceptor heterojunction at the nanometer scale, to ensure efficient charge generation and loss-free charge transport at the same time. Here, we present a method for the controlled, sequential design of a bilayer polymer cell architecture that consists of a large interface area with connecting paths to the respective electrodes for both materials. We used the surface-directed demixing of a donor conjugated/guest polymer blend during spin coating to produce a nanostructured interface, which was, after removal of the guest with a selective solvent, covered with an acceptor layer. With use of a donor poly(p-phenylenevinylene) derivative and the acceptor C-60 fullerene, this resulted in much-improved device performance, with external power efficiencies more than 3 times higher than those reported for that particular material combination so far.

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It is well known that radiation causes mutation, and that mutations are generally deleterious. They can lead to disease, malformation and death. It is further known that we live in a radioactive world. The air, the soil, the water, the food, all are somewhat radioactive. Natural radiation is not uniformly distributed throughout the earth's crust. There are some areas, especially in Brazil and India, where the levels of background radiation are several times higher than generally obtains. We have undertaken a specially prepared house-to-house genetic-epidemiologic, retrospective survey in a large Brazilian area with levels of natural radiation ranging from 7 (normal) to 133 (high) micro-roentgens per hour. In all, 24 different localities were surveyed during a period of 10 months by a trained team of nurses and social assistants. Our total sample consists of more than 8,000 couples who have had almost 44,000 pregnancy terminations. Our results do not disprove that natural radiation is one of the causes of socalled spontaneous mutations. They only show that, under the conditions of this study, no detectable effect on abortion was found. Our results also attest to the importance of extraneous variables in the analysis of morbidity and mortality data.

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Macroecology evaluates the partitioning of physical space and resources among organisms through correlation among ecological variables, such as geographical range size and shape, body size, and population density, measured at large geographical and taxonomic scales. In this article, we analyzed the spatial patterns in worker body size and geographic range size for the 27 described species of honey ants, genus Myrmecocystus Wesmael, in the United States and Mexico, and especially the relationship between these 2 variables after statistically removing their spatial patterns. The 2 variables are correlated, but also displayed significant spatial patterns, as detected by trend surface and spatial autocorrelation analyses. After removing these spatial effects, worker body size and geographic range size were still positively correlated. The relationship, therefore, is not a consequence of spatial effects and it does follow Brown's model, which predicts that the geographic range size will have a positive slope on body size. In this model, the lower population densities caused by foraging activities and local territorial competition are associated with a large geographic range, avoiding stochastic extinction. Although this constraint in local population density does not necessarily hold for small organisms such as insects that could achieve high densities even in very small areas and patchy habitats, it may hold for social insects, especially ants, because of the local competition among colonies.

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Random amplified polymorphic DNA (RAPD) technique was used to examine the genetic variability on an endangered Neotropical fish species, Brycon lundii, collected on two regions with distinct environmental conditions in the São Francisco River (Brazil), downstream from a hydroelectric station. Using decamer oligonucleotides as single primers in Polymerase Chain Reaction (PCR), genetic similarity index, mean allele frequency and mean heterozigosity were estimated, revealing variations between samples from the two regions. Moreover, a fragment of about 1200 base pairs was found in 100% of the examined animals collected at the region closer to the hydroelectric dam, while its frequency was much lower (27.3%) within the sample from the second collecting site, 30 km downstream from the dam, indicating a possible correlation between genetic variation and geographical area. A dendogram representing the relationships among genotypes was obtained, demonstrating at least two major clusters of animals. Based on the data, a model of population structuring in Brycon lundii is suggested. The described approach holds great promise for further analyses and gives support to biodiversity maintenance and recovery efforts of B. lundii.

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Recent and historical biomarkers assess chronic or subchronic exposure to fluoride. The most studied recent biomarkers are nails and hair. Both can be non-invasively obtained, although collection of nails is more accepted by the subjects. External contamination may be a problem for both biomarkers and still needs to be better evaluated. Nails have been more extensively studied. Although the available knowledge does not allow their use as predictors of dental fluorosis by individual subjects, since reference values of fluoride have not yet been established, they have a strong potential for use in epidemiological surveys. Toenails should be preferred instead of fingernails, and variables that are known to affect nail fluoride concentrations - such as age, gender and geographical area - should be considered. The main historical biomarkers that could indicate total fluoride body burden are bone and dentin. Of these, bone is more studied, but its fluoride concentrations vary according to the type of bone and subjects' age and gender. They are also influenced by genetic background, renal function and remodeling rate, variables that complicate the establishment of a normal range of fluoride levels in bone that could indicate 'desirable' exposure to fluoride. The main issue when attempting to use bone as biomarker of fluoride exposure is the difficulty and invasiveness of sample collection. In this aspect, collection of dentin, especially from 3rd molars that are commonly extracted, is advantageous. However, mean values also span a wide range and reference concentrations have not been published yet. © 2011 S. Karger AG, Basel.

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