901 resultados para Subfractals, Subfractal Coding, Model Analysis, Digital Imaging, Pattern Recognition


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We have devised a microspectroscopic strategy for assessing the intracellular (re)distribution and the integrity of the primary structure of proteins involved in signal transduction. The purified proteins are fluorescent-labeled in vitro and reintroduced into the living cell. The localization and molecular state of fluorescent-labeled protein kinase C beta I isozyme were assessed by a combination of quantitative confocal laser scanning microscopy, fluorescence lifetime imaging microscopy, and novel determinations of fluorescence resonance energy transfer based on photobleaching digital imaging microscopy. The intensity and fluorescence resonance energy transfer efficiency images demonstrate the rapid nuclear translocation and ensuing fragmentation of protein kinase C beta I in BALB/c3T3 fibroblasts upon phorbol ester stimulation, and suggest distinct, compartmentalized roles for the regulatory and catalytic fragments.

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Introdução: As doenças cardiovasculares são a principal causa de morte no Brasil e no mundo e apresentam importante contribuição para a carga global de doenças. A dieta tem sido considerada um dos determinantes primários do estado de saúde dos indivíduos, atuando na modulação dos fatores de risco metabólicos para doença cardiovascular. Objetivos: Desenvolver um modelo conceitual para a relação entre fatores de risco metabólicos e investigar sua associação com padrões de dieta de adultos e idosos residentes no município de São Paulo. Métodos: Estudo transversal de base populacional com amostra probabilística de adultos e idosos, residentes em área urbana do município de São Paulo, que participaram do Inquérito de Saúde do Município de São Paulo, realizado em duas fases entre os anos de 2008 e 2011 (estudo ISA Capital 2008). Na primeira fase do estudo, 1.102 adultos e idosos, de ambos os sexos, foram entrevistados no domicílio, por meio da aplicação de questionário estruturado e do recordatório alimentar de 24 horas. Na segunda fase, 642 indivíduos adultos e idosos foram reavaliados quanto ao consumo alimentar por meio da aplicação, por telefone, do segundo recordatório alimentar, e, destes, 592 participaram da coleta domiciliar de amostras de sangue venoso, da medição antropométrica e da aferição da pressão arterial por técnico de enfermagem. Os alimentos relatados em ambos os recordatórios foram agrupados segundo a similaridade do valor nutricional e hábitos alimentares da população, e corrigidos pela variância intrapessoal da ingestão por procedimentos estatísticos da plataforma online Multiple Source Method. Os grupos de alimentos foram analisados por meio de análise fatorial exploratória e confirmatória (manuscrito 1) e por modelos de equações estruturais exploratórios (manuscrito 3), a fim de obter os padrões de dieta. O modelo conceitual da relação entre os fatores de risco metabólicos (leptina sérica, proteína C-reativa de alta sensibilidade sérica, pressão arterial sistólica e diastólica, razão colesterol total/lipoproteína de alta densidade, razão triacilglicerol/lipoproteína de alta densidade, glicemia de jejum plasmática, circunferência da cintura e peso corporal) foi obtido por modelos de equações estruturais estratificados por sexo (manuscrito 2). Por fim, a associação dos padrões de dieta com o modelo conceitual proposto (manuscrito 3) foi investigada por modelos de equações estruturais exploratórios. Índices de qualidade de ajuste foram estimados para avaliar a adequação de todos os modelos. As análises foram realizadas no programa Mplus versão 6.12. Resultados: No manuscrito 1, a análise fatorial exploratória revelou a existência de dois padrões de dieta, os quais apresentaram boa qualidade de ajuste na análise fatorial confirmatória quando aplicados os pontos de corte de cargas fatoriais |0,25| na rotação oblíqua Promax. No manuscrito 2, a relação entre os fatores de risco metabólicos foi diferente entre os sexos. Nas mulheres, a leptina sérica apresentou efeitos indiretos e positivos, mediados pelo peso corporal e pela circunferência da cintura, em todos os fatores de risco avaliados. Já nos homens, a leptina sérica apresentou efeitos diretos e positivos sobre a proteína C-reativa de alta sensibilidade e efeitos indiretos e positivos (mediados pelo peso corporal e pela circunferência da cintura) sobre a razão triacilglicerol/lipoproteína de alta densidade, colesterol total/lipoproteína de alta densidade e glicemia de jejum plasmática. No manuscrito 3, foram obtidos três padrões de dieta, dos quais o Tradicional apresentou relação direta e negativa com a leptina sérica e relação indireta e negativa com o peso corporal e a circunferência da cintura, bem como com os demais fatores de risco metabólicos. Já o padrão Prudente apresentou relação direta e negativa com a pressão arterial sistólica, enquanto o padrão Moderno não se associou aos fatores de risco metabólicos investigados. Conclusão: Diferenças nos padrões de dieta de acordo com o tipo de rotação fatorial empregada foram observadas. A relação entre os fatores de risco metabólicos para doença cardiovascular foi distinta entre homens e mulheres, sendo a leptina um dos possíveis hormônios envolvidos. Os padrões de dieta Tradicional e Prudente associaram-se inversamente com os fatores de risco metabólicos, desempenhando uma importante estratégia de prevenção e controle às doenças cardiovasculares no país.

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Despite the vast research examining the evolution of Caribbean education systems, little is chronologically tied to the postcolonial theoretical perspectives of specific island-state systems, such as the Jamaican education system and its relationship with the underground shadow education system. This dissertation study sought to address the gaps in the literature by critically positioning postcolonial theories in education to examine the macro- and micro-level impacts of extra lessons on secondary education in Jamaica. The following postcolonial theoretical (PCT) tenets in education were contextualized from a review of the literature: (a) PCT in education uses colonial discourse analysis to critically deconstruct and decolonize imperialistic and colonial representations of knowledge throughout history; (b) PCT in education uses an anti-colonial discursive framework to re-position indigenous knowledge in schools, colleges, and universities to challenge hegemonic knowledge; (c) PCT in education involves the "unlearning" of dominant, normative ideologies, the use of self-reflexivity, and deconstruction; and (d) PCT in education calls for critical pedagogical approaches that reject the banking concept of education and introduces inclusive pedagogy to facilitate "the passage from naïve to critical transitivity" (Freire, 1973, p. 32). Specifically, using a transformative mixed-methods design, grounded and informed by a postcolonial theoretical lens, I quantitatively uncovered and then qualitatively highlighted how if at all extra lessons can improve educational outcomes for students at the secondary level in Jamaica. Accordingly, the quantitative data was used to test the hypotheses that the practice of extra lessons in schools is related to student academic achievement and the practice of critical-inclusive pedagogy in extra lessons is related to academic achievement. The two-level hierarchical linear model analysis revealed that hours spent in extra lessons, average household monthly income, and critical-inclusive pedagogical tents were the best predictors for academic achievement. Alternatively, the holistic multi-case study explored how extra-lessons produces increased academic achievement. The data revealed new ways of knowledge construction and critical pedagogical approaches to galvanize systemic change in secondary education. Furthermore, the data showed that extra lessons can improve educational outcomes for students at the secondary level if the conditions for learning are met. This study sets the stage for new forms of knowledge construction and implications for policy change.

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Since the fall of the Wall, Eastern Germans have drastically changed their demographic behavior. Marriages and births have dropped to an unprecedented low level. Our paper tracks birth rates of the East German population, past, present, and future. We propose a simulation model of future cohort fertility. The hypotheses we develop build on the historical record of reproductive behavior in the German Democratic Republic (GDR) since 1960 and on an analysis of the pattern of change between 1990 and 1994. The particular emphasis lies in the assumption that East German couples will rapidly westernize their family size by trying to reach completed fertility levels of the corresponding West German cohort. This implies that the resulting adaptation process includes the postunification crisis as a logical first step.

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"Supported in part by the Department of Computer Science and the Atomic Energy Commission under contract US AEC AT(11-1)2118."

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"C00-2118-0048."

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"January 1985."

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Selection of machine learning techniques requires a certain sensitivity to the requirements of the problem. In particular, the problem can be made more tractable by deliberately using algorithms that are biased toward solutions of the requisite kind. In this paper, we argue that recurrent neural networks have a natural bias toward a problem domain of which biological sequence analysis tasks are a subset. We use experiments with synthetic data to illustrate this bias. We then demonstrate that this bias can be exploitable using a data set of protein sequences containing several classes of subcellular localization targeting peptides. The results show that, compared with feed forward, recurrent neural networks will generally perform better on sequence analysis tasks. Furthermore, as the patterns within the sequence become more ambiguous, the choice of specific recurrent architecture becomes more critical.

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Recent large-scale analyses of mainly full-length cDNA libraries generated from a variety of mouse tissues indicated that almost half of all representative cloned sequences did flat contain ail apparent protein-coding sequence, and were putatively derived from non-protein-coding RNA (ncRNA) genes. However, many of these clones were singletons and the majority were unspliced, raising the possibility that they may be derived from genomic DNA or unprocessed pre-rnRNA contamination during library construction, or alternatively represent nonspecific transcriptional noise. Here we Show, using reverse transcriptase-dependent PCR, microarray, and Northern blot analyses, that many of these clones were derived from genuine transcripts Of unknown function whose expression appears to be regulated. The ncRNA transcripts have larger exons and fewer introns than protein-coding transcripts. Analysis of the genomic landscape around these sequences indicates that some cDNA clones were produced not from terminal poly(A) tracts but internal priming sites within longer transcripts, only a minority of which is encompassed by known genes. A significant proportion of these transcripts exhibit tissue-specific expression patterns, as well as dynamic changes in their expression in macrophages following lipopolysaccharide Stimulation. Taken together, the data provide strong support for the conclusion that ncRNAs are an important, regulated component of the mammalian transcriptome.

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This paper presents a way to describe design patterns rigorously based on role concepts. Rigorous pattern descriptions are a key aspect for patterns to be used as rules for model evolution in the MDA context, for example. We formalize the role concepts commonly used in defining design patterns as a role metamodel using Object-Z. Given this role metamodel, individual design patterns are specified generically as a formal pattern role model using Object-Z. We also formalize the properties that must be captured in a class model when a design pattern is deployed. These properties are defined generically in terms of role bindings from a pattern role model to a class model. Our work provides a precise but abstract approach for pattern definition and also provides a precise basis for checking the validity of pattern usage in designs.

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O presente estudo disserta sobre o papel da indústria, com foco nos fabricantes de televisores e sua participação na implantação e desenvolvimento da TV Digital no Brasil, como os primeiros atores desse cenário a apontar o norte para a viabilização de um modelo de negócio para a Televisão Digital (TVD) e Televisão Digital Interativa (TVDI): a TV Conectada e a TV Inteligente. Faz um levantamento histórico do tema desde o Governo FHC, passando pelo Governo Lula até o atual Governo Dilma. O texto apresenta os desafios técnico, político e econômico dessa implementação. Pretende identificar os acertos e enganos dos atores envolvidos nesse cenário, montado para a implementação do sistema digital da TV brasileira. Ressalta os interesses, nem sempre harmônicos, de todos os envolvidos: do capital, com foco no lucro; do governo, com seus acordos políticos, muitas vezes contrapondo ao cumprimento de seu papel de representante dos interesses da maioria da população brasileira; e da dinâmica científico tecnológico-industrial, que necessita de campo fértil, propício e contínuo para se desenvolver.(AU)

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This thesis seeks to describe the development of an inexpensive and efficient clustering technique for multivariate data analysis. The technique starts from a multivariate data matrix and ends with graphical representation of the data and pattern recognition discriminant function. The technique also results in distances frequency distribution that might be useful in detecting clustering in the data or for the estimation of parameters useful in the discrimination between the different populations in the data. The technique can also be used in feature selection. The technique is essentially for the discovery of data structure by revealing the component parts of the data. lhe thesis offers three distinct contributions for cluster analysis and pattern recognition techniques. The first contribution is the introduction of transformation function in the technique of nonlinear mapping. The second contribution is the us~ of distances frequency distribution instead of distances time-sequence in nonlinear mapping, The third contribution is the formulation of a new generalised and normalised error function together with its optimal step size formula for gradient method minimisation. The thesis consists of five chapters. The first chapter is the introduction. The second chapter describes multidimensional scaling as an origin of nonlinear mapping technique. The third chapter describes the first developing step in the technique of nonlinear mapping that is the introduction of "transformation function". The fourth chapter describes the second developing step of the nonlinear mapping technique. This is the use of distances frequency distribution instead of distances time-sequence. The chapter also includes the new generalised and normalised error function formulation. Finally, the fifth chapter, the conclusion, evaluates all developments and proposes a new program. for cluster analysis and pattern recognition by integrating all the new features.

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Component-based development (CBD) has become an important emerging topic in the software engineering field. It promises long-sought-after benefits such as increased software reuse, reduced development time to market and, hence, reduced software production cost. Despite the huge potential, the lack of reasoning support and development environment of component modeling and verification may hinder its development. Methods and tools that can support component model analysis are highly appreciated by industry. Such a tool support should be fully automated as well as efficient. At the same time, the reasoning tool should scale up well as it may need to handle hundreds or even thousands of components that a modern software system may have. Furthermore, a distributed environment that can effectively manage and compose components is also desirable. In this paper, we present an approach to the modeling and verification of a newly proposed component model using Semantic Web languages and their reasoning tools. We use the Web Ontology Language and the Semantic Web Rule Language to precisely capture the inter-relationships and constraints among the entities in a component model. Semantic Web reasoning tools are deployed to perform automated analysis support of the component models. Moreover, we also proposed a service-oriented architecture (SOA)-based semantic web environment for CBD. The adoption of Semantic Web services and SOA make our component environment more reusable, scalable, dynamic and adaptive.