115 resultados para Atlases


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Basic structure studies of the biosynthetic machinery of the cell by electron microscopy (EM) have underpinned much of our fundamental knowledge in the areas of molecular cell biology and membrane traffic. Driven by our collective desire to understand how changes in the complex and dynamic structure of this enigmatic organelle relate to its pivotal roles in the cell, the comparatively high-resolution glimpses of the Golgi and other compartments of the secretory pathway offered to us through EM have helped to inspire the development and application of some of our most informative, complimentary (molecular, biochemical and genetic) approaches. Even so, no one has yet even come close to relating the basic molecular mechanisms of transport, through and from the Golgi, to its ultrastructure, to everybody's satisfaction. Over the past decade, EM tomography has afforded new insights into structure -function relationships of the Golgi and provoked a re-evaluation of older paradigms. By providing a set of tools for structurally dissecting cells at high-resolution in three-dimensions (3D), EM tomography has emerged as a method for studying molecular cell biology in situ. As we move rapidly toward the establishment of molecular atlases of organelles through advances in proteomics and genomics, tomographic studies of the Golgi offer the tantalizing possibility that one day, we will be able to map the spatio-temporal coordinates of Golgi-related proteins and lipids accurately in the context of 4D cellular space. (c) 2005 Elsevier B.V. All rights reserved.

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Brain anatomy is characterized by dramatic growth from the end of the second trimester through the neonatal stage. The characterization of normal axonal growth of the white matter tracts has not been well-documented to date and could provide important clues to understanding the extensive inhomogeneity of white matter injuries in cerebral palsy (CP) patients. However, anatomical studies of human brain development during this period are surprisingly scarce and histology-based atlases have become available only recently. Diffusion tensor magnetic resonance imaging (DTMRI) can reveal detailed anatomy of white matter. We acquired diffusion tensor images (DTI) of postmortem fetal brain samples and in vivo neonates and children. Neural structures were annotated in two-dimensional (2D) slices, segmented, measured, and reconstructed three-dimensionally (3D). The growth status of various white matter tracts was evaluated on cross-sections at 19-20 gestational weeks, and compared with 0-month-old neonates and 5- to 6-year-old children. Limbic, commissural, association, and projection white matter tracts and gray matter structures were illustrated in 3D and quantitatively characterized to assess their dynamic changes. The overall pattern of the time courses for the development of different white matter is that limbic fibers develop first and association fibers last and commissural and projection fibers are forming from anterior to posterior part of the brain. The resultant DTNIRI-based 3D human brain data will be a valuable resource for human brain developmental study and will provide reference standards for diagnostic radiology of premature newborns. (c) 2006 Elsevier Inc. All rights reserved.

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The paper presents a computational analysis of Bulgarian dialect variation, concentrating on pronunciation differences. It describes the phonetic data set compiled during the project* ‘Measuring Linguistic Unity and Diversity in Europe’ that consists of the pronunciations of 157 words collected at 197 sites from all over Bulgaria. We also present the results of analyzing this data set using various quantitative methods and compare them to the traditional scholarship on Bulgarian dialects. The results have shown that various dialectometrical techniques clearly identify east-west division of the country along the ‘jat’ border, as well as the third group of varieties in the Rodopi area. The rest of the groups specified in the traditional atlases either were not confirmed or were confirmed with a low confidence.

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This dissertation establishes the foundation for a new 3-D visual interface integrating Magnetic Resonance Imaging (MRI) to Diffusion Tensor Imaging (DTI). The need for such an interface is critical for understanding brain dynamics, and for providing more accurate diagnosis of key brain dysfunctions in terms of neuronal connectivity. ^ This work involved two research fronts: (1) the development of new image processing and visualization techniques in order to accurately establish relational positioning of neuronal fiber tracts and key landmarks in 3-D brain atlases, and (2) the obligation to address the computational requirements such that the processing time is within the practical bounds of clinical settings. The system was evaluated using data from thirty patients and volunteers with the Brain Institute at Miami Children's Hospital. ^ Innovative visualization mechanisms allow for the first time white matter fiber tracts to be displayed alongside key anatomical structures within accurately registered 3-D semi-transparent images of the brain. ^ The segmentation algorithm is based on the calculation of mathematically-tuned thresholds and region-detection modules. The uniqueness of the algorithm is in its ability to perform fast and accurate segmentation of the ventricles. In contrast to the manual selection of the ventricles, which averaged over 12 minutes, the segmentation algorithm averaged less than 10 seconds in its execution. ^ The registration algorithm established searches and compares MR with DT images of the same subject, where derived correlation measures quantify the resulting accuracy. Overall, the images were 27% more correlated after registration, while an average of 1.5 seconds is all it took to execute the processes of registration, interpolation, and re-slicing of the images all at the same time and in all the given dimensions. ^ This interface was fully embedded into a fiber-tracking software system in order to establish an optimal research environment. This highly integrated 3-D visualization system reached a practical level that makes it ready for clinical deployment. ^

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Chronic non-communicable diseases represent a major public health problem, requiring more effective investigation and control by government agencies. The aim of this study was to correlate the mortality rate for oral cancer in Brazilian State capitals from 1998 to 2002 with socioeconomic factors collected in the 2000 census, using an ecological study design. Data were obtained from the Mortality Information System from 1998 to 2002. Social factors were taken from the Brazilian Human Development Atlases. After data collection, statistical analysis was performed using Pearson's correlation index. The findings included positive and significant correlations among the socioeconomic indicators (Municipal Human Development Index - MHDI, MHDI-income, MHDI-education, MHDI-life expectancy, and per capita income), and negative and significant correlations with the socioeconomic indicators Gini Index and infant mortality. Despite the study’s limitations and probable underreporting in less developed State capitals, the study found significant statistic correlations between the selected socioeconomic indicators and the oral cancer mortality rate___________________________RESUMO As doenças crônico-degenerativas representam um grande problema de saúde pública, necessitando de levantamento e controle mais efetivos destas enfermidades por parte dos órgãos públicos. O objetivo deste estudo foi correlacionar os índices de mortalidade por câncer oral nas capitais do Brasil no período de 1998 a 2002 com indicadores sócio-econômicos do Censo Demográfico de 2000 , por meio de um estudo do tipo ecológico. Os dados foram extraídos do Sistema de Informação de Mortalidade (Ministério da Saúde/DATASUS), para os anos de 1998-2002. Os indicadores sócio-econômicos foram obtidos a partir do Atlas do Desenvolvimento Humano no Brasil. Após coleta dos dados, a análise estatística foi realizada usando-se o índice de correlação de Pearson. Observaram-se corre- lações positivas e significativas entre os indicadores sócio-econômicos (Índice de Desenvolvimento HumanoMunicipal – IDH-M, IDH-M renda, IDH-M educação, IDH-M longevidade e renda per capita), e correlação negativa e significante para os indicadores sócio-econômicos índice de Gini e mortalidade infantil. Apesar das limitações do estudo e da provável problemática de sub-registros nas capitais menos desenvolvidas, o presente trabalho encontrou correlações estatisticamente significantes entre os indicadores sócio-econômicos selecionados e o índice de mortalidade por câncer oral

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RODRIGUES, Katamara et al. Prevalence of orofacial clefts and social factors in Brazil. Brazilian oral research, v.23, n. 1, p. 38-42, 2009.Disponivel em: . Acesso em: 04 out. 2010.

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Ivar Refsdal’s school atlases were the most used school atlases in Norway for most of the 20th century. The article shows that his maps where highly appreciated by his contemporary citizens as a new mean for geography education in Norwegian schools. Making maps always means choices of content and mapmaking technique. Therefor the article is discussing some of the map making choices made by Refsdal to display the world for the students.

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BORGES,D. M. L.et al. Mortalidade por câncer de boca e condição sócio-econômica no Brasil.Cad. Saúde Pública, Rio de Janeiro, v.25,n.2, p.321-327, fev, 2009

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RODRIGUES, Katamara et al. Prevalence of orofacial clefts and social factors in Brazil. Brazilian oral research, v.23, n. 1, p. 38-42, 2009.Disponivel em: . Acesso em: 04 out. 2010.

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This article aims at analyzing the lexical maps of three linguistic atlases from Paraná: two related to the city of Londrina (AGUILERA, 1987 and ROMANO, 2012) and one related to the State of Paraná, the Linguistic Atlas of Paraná (AGUILERA, 1994), concerning the variants for espadrilles. As these are popular shoes that are falling out of use in Paraná, with this work our objective is to verify and discuss: (i) by means of real time and apparent time research (LABOV, 1996 [1972]), in two synchronies, the changes and resistances of the lexical units in the speech of people from Londrina; (ii) the lexical collection found in the three atlases and its dicionarization; (iii) how the creation of popular forms to name such popular shoes at the beginning of the colonization in the north of Paraná happens