947 resultados para multidimensional overlap
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Peripheral T-cell lymphomas (PTCLs) represent a heterogeneous group of more than 20 neoplastic entities derived from mature T cells and natural killer (NK) cells involved in innate and adaptive immunity. With few exceptions these malignancies, which may present as disseminated, predominantly extranodal or cutaneous, or predominantly nodal diseases, are clinically aggressive and have a dismal prognosis. Their diagnosis and classification is hampered by several difficulties, including a significant morphological and immunophenotypic overlap across different entities, and the lack of characteristic genetic alterations for most of them. Although there is increasing evidence that the cell of origin is a major determinant for the delineation of several PTCL entities, however, the cellular derivation of most entities remains poorly characterized and/or may be heterogeneous. The complexity of the biology and pathophysiology of PTCLs has been only partly deciphered. In recent years, novel insights have been gained from genome-wide profiling analyses. In this review, we will summarize the current knowledge on the pathobiological features of peripheral NK/T-cell neoplasms, with a focus on selected disease entities manifesting as tissue infiltrates primarily in extranodal sites and lymph nodes.
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O acesso à informação é um elemento-chave para o desenvolvimento econômico e social de comunidades e grupos sociais. A capacidade de obter informações, além dos contornos restritos da própria comunidade, é parte do capital relacional dos indivíduos e grupos. As transformações dependem das redes existentes entre os indivíduos do grupo e atores localizados em outros espaços sociais, ou seja, do capital social da comunidade. Por ser tratado como capital, da mesma forma que o capital humano ou financeiro, investimentos para sua ampliação devem permitir retornos ou benefícios, servindo de base para o desenvolvimento, o que tem sido amplamente pesquisado. O uso da metodologia de análise de redes sociais vem se difundindo rapidamente, nos últimos anos, trazendo contribuições significativas para a compreensão do papel do capital social no desenvolvimento. A construção de redes sociais e a conseqüente aquisição de capital social estão condicionadas por fatores culturais, políticos e sociais. O próprio conceito de capital social é multidimensional, o que significa incorporar vários níveis e unidades de análise. A combinação da metodologia de análise de redes com uma base teórica sólida amplia os espaços de pesquisa, em um espectro que vai das pesquisas sobre o acesso às informações básicas sobre saúde pública em comunidades urbanas ao comércio internacional, passando pela análise do desenvolvimento regional, através do estudo dos arranjos produtivos locais.
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Analizando los sitios web de universidades de diferentes países es posible construir mapas que reflejen gráficamente las relaciones que se establecen entre ellas, utilizando para ello nuevas técnicas de representación de la información como el análisis de cocitación de sitios web (análisis de cositación) y el escalamiento multidimensional (MDS). Pretendemos demostrar que estas relaciones no son ajenas al mundo real, y que siguen un patrón político, en lugar de un patrón académico, permitiéndonos construir auténticos "mapas geopolíticos" de Internet. Proponemos utilizar este tipo de representaciones como una herramienta para el análisis sociopolítico de la realidad, ya que con estos mapas obtenemos una instantánea de una región geográfica y un momento determinado, de la que es posible extraer nueva y valiosa información.
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Multisensory and sensorimotor integrations are usually considered to occur in superior colliculus and cerebral cortex, but few studies proposed the thalamus as being involved in these integrative processes. We investigated whether the organization of the thalamocortical (TC) systems for different modalities partly overlap, representing an anatomical support for multisensory and sensorimotor interplay in thalamus. In 2 macaque monkeys, 6 neuroanatomical tracers were injected in the rostral and caudal auditory cortex, posterior parietal cortex (PE/PEa in area 5), and dorsal and ventral premotor cortical areas (PMd, PMv), demonstrating the existence of overlapping territories of thalamic projections to areas of different modalities (sensory and motor). TC projections, distinct from the ones arising from specific unimodal sensory nuclei, were observed from motor thalamus to PE/PEa or auditory cortex and from sensory thalamus to PMd/PMv. The central lateral nucleus and the mediodorsal nucleus project to all injected areas, but the most significant overlap across modalities was found in the medial pulvinar nucleus. The present results demonstrate the presence of thalamic territories integrating different sensory modalities with motor attributes. Based on the divergent/convergent pattern of TC and corticothalamic projections, 4 distinct mechanisms of multisensory and sensorimotor interplay are proposed.
Integrative analyses of speciation and divergence in Psammodromus hispanicus (Squamata: Lacertidae).
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BackgroundGenetic, phenotypic and ecological divergence within a lineage is the result of past and ongoing evolutionary processes, which lead ultimately to diversification and speciation. Integrative analyses allow linking diversification to geological, climatic, and ecological events, and thus disentangling the relative importance of different evolutionary drivers in generating and maintaining current species richness.ResultsHere, we use phylogenetic, phenotypic, geographic, and environmental data to investigate diversification in the Spanish sand racer (Psammodromus hispanicus). Phylogenetic, molecular clock dating, and phenotypic analyses show that P. hispanicus consists of three lineages. One lineage from Western Spain diverged 8.3 (2.9-14.7) Mya from the ancestor of Psammodromus hispanicus edwardsianus and P. hispanicus hispanicus Central lineage. The latter diverged 4.8 (1.5-8.7) Mya. Molecular clock dating, together with population genetic analyses, indicate that the three lineages experienced northward range expansions from southern Iberian refugia during Pleistocene glacial periods. Ecological niche modelling shows that suitable habitat of the Western lineage and P. h. edwardsianus overlap over vast areas, but that a barrier may hinder dispersal and genetic mixing of populations of both lineages. P. h. hispanicus Central lineage inhabits an ecological niche that overlaps marginally with the other two lineages.ConclusionsOur results provide evidence for divergence in allopatry and niche conservatism between the Western lineage and the ancestor of P. h. edwardsianus and P. h. hispanicus Central lineage, whereas they suggest that niche divergence is involved in the origin of the latter two lineages. Both processes were temporally separated and may be responsible for the here documented genetic and phenotypic diversity of P. hispanicus. The temporal pattern is in line with those proposed for other animal lineages. It suggests that geographic isolation and vicariance played an important role in the early diversification of the group, and that lineage diversification was further amplified through ecological divergence.
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The problem of prediction is considered in a multidimensional setting. Extending an idea presented by Barndorff-Nielsen and Cox, a predictive density for a multivariate random variable of interest is proposed. This density has the form of an estimative density plus a correction term. It gives simultaneous prediction regions with coverage error of smaller asymptotic order than the estimative density. A simulation study is also presented showing the magnitude of the improvement with respect to the estimative method.
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In this note we prove an existence and uniqueness result for the solution of multidimensional stochastic delay differential equations with normal reflection. The equations are driven by a fractional Brownian motion with Hurst parameter H > 1/2. The stochastic integral with respect to the fractional Brownian motion is a pathwise Riemann¿Stieltjes integral.
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In a recent paper, Komaki studied the second-order asymptotic properties of predictive distributions, using the Kullback-Leibler divergence as a loss function. He showed that estimative distributions with asymptotically efficient estimators can be improved by predictive distributions that do not belong to the model. The model is assumed to be a multidimensional curved exponential family. In this paper we generalize the result assuming as a loss function any f divergence. A relationship arises between alpha connections and optimal predictive distributions. In particular, using an alpha divergence to measure the goodness of a predictive distribution, the optimal shift of the estimate distribution is related to alpha-covariant derivatives. The expression that we obtain for the asymptotic risk is also useful to study the higher-order asymptotic properties of an estimator, in the mentioned class of loss functions.
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This paper is devoted to prove a large-deviation principle for solutions to multidimensional stochastic Volterra equations.
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Los telecentros españoles constituyen un instrumento de dinamización e inclusión social en la sociedad de la información. Sin embargo, existe una ausencia de indicadores de impacto que permitan evaluar las transformaciones sociales que originan estas entidades en sus áreas de influencia. Teniendo en cuenta este aspecto se formula un sistema de evaluación basado en indicadores y en el método de análisis multivariable "Rango Selectivo Multidimensional" (RSM) con el objeto de medir el impacto de estas entidades en la sociedad de la información.
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Mais recentemente, o impacto dos avanços tecnológicos aplicados à educação contribuiu para o aprimoramento das metodologias utilizadas no ensino. Um reflexo disto reside no aperfeiçoamento dos instrumentos educacionais, trabalhados aqui como os textos e mapas conceituais, que partem em busca de um caráter mais significativo, inspirado na teoria ausubeliana, permitindo, por meio da ferramenta computacional, o aumento de sua interação e expansão a outras fronteiras como as do mundo multidimensional. Com base nestes avanços, este artigo apresenta abordagens diferenciadas, articuladas com a visão epistêmica do filósofo da ciência Gaston Bachelard às práticas educacionais tradicionais referentes ao uso de textos e mapas conceituais, principalmente quando aplicados em temas relacionados às ciências, a fim de trazer à tona mais uma possibilidade de trabalho no meio educacional.
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This thesis examines the interplay between state regulation and the way organisations define performance. Performance is generally understood to be a multidimensional concept, but the extent to which its different facets are shaped by regulation remains an understudied question. This thesis aims to address this question and provide at least a partial answer to it. To do so, it examines whether the level of regulation amplifies or abates the multidimensionality of regulated entities' performance definition, i.e. the way they define the concept of performance. The leading question is whether an organisation's performance definition can be associated with the regulatory intensity its environment confronts it with. Moreover, the study explores whether the type of ownership-public or private-plays a role in regard to how a regulated entity defines performance. In order to undertake this investigation, the thesis focuses on the performance definitions of organisations in six different sport betting and lottery regulations. Qualitative data is gathered from primary and secondary documents as well as through semi-structured interviews with chief executive officers (CEO), members of executive management and gambling experts in each of these countries. The thesis concludes that the performance definitions of the organisations under study are indeed multidimensional, as well as clearly influenced by their respective regulatory environments. However, not all performance dimensions identified in the literature are present, nor can they all be estimated to be part of the performance definition. In addition, the public-private difference in defining performance-as conceptualised in the literature- seems to be abated in a regulated environment. The central role played by regulation in regard to the multidimensionality of the performance definition partially outweighs the effect of the nature of ownership.
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Este trabajo trata de explicar los motivos que han llevado a los partidos políticos españoles a optar, en los procesos de formación de gobierno en situaciones parlamentarias minoritarias celebrados desde 1977, por la formación de gobiernos minoritarios. Contrariamente a lo sostenido por las teorías formales de las coaliciones políticas, la solución al proceso de formación de gobierno en el caso español responde a los cálculos estratégicos de los partidos políticos implicados en el fenómeno coalicional. Como se argumentará, la formación de gobiernos minoritarios en España se configura como soluciones racionales desde una óptica metodológica multidimensional.
Resumo:
O principal objetivo deste trabalho foi verificar se a suposição de predominância da agricultura familiar na microbacia do Taquara Branca, Sumaré, SP, poderia ser sustentada com base em informações concretas. Foi possível a utilização de amostragem probabilística, pois estava disponível um mapa com os limites das 106 propriedades da microbacia, sendo sorteadas 33 delas para a aplicação de questionários do tipo cross-section. A técnica multivariada empregada foi a análise de agrupamentos, para a qual foi utilizado o procedimento PROC CLUSTER do SAS. Nessa análise só foram considerados os dados referentes aos 22 respondentes que exerciam atividade agrícola. Após a análise unidimensional, algumas perguntas foram selecionadas com base na variabilidade entre as respostas e, a partir destas, construíram-se as variáveis necessárias para se proceder à análise multidimensional. A análise de agrupamento permitiu identificar claramente três grupos naturais entre as 22 propriedades. De acordo com as características dos componentes de cada grupo, foi possível classificá-los em: grupo 1, doze propriedades de agricultura familiar; grupo 2, seis propriedades de agricultura não familiar em pequenas áreas; e grupo 3, quatro propriedades de agricultura não familiar em grandes áreas. Embora não seja predominante (apenas 36%), a agricultura familiar é o grupo mais freqüente na microbacia do Taquara Branca.
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General internal medicine (GIM) has flourished in the United States (U.S.). Unlike other subspecialties of internal medicine, however, GIM's evolution has not been global in scope, but rather appears to have occurred in isolation within countries. Here, we describe international models of GIM from Canada, Switzerland, Australia/New Zealand, Argentina, and Japan, and compare these with the U.S. model. There are notable differences in the typical clinical roles assumed by General Internists across these 7 countries, but also important overlap in clinical and academic domains. Despite this overlap, there has been a relative lack of contact among General Internists from these and other countries at a truly international GIM meeting; the time is now for increased international exchange and the "globalization" of GIM.