987 resultados para SILVA, JOSE ASUNCION


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In this report, we describe the microfabrication and integration of planar electrodes for contactless conductivity detection on polyester-toner (PT) electrophoresis microchips using toner masks. Planar electrodes were fabricated by three simple steps: (i) drawing and laser-printing the electrode geometry on polyester films, (ii) sputtering deposition onto substrates, and (iii) removal of toner layer by a lift-off process. The polyester film with anchored electrodes was integrated to PT electrophoresis microchannels by lamination at 120 degrees C in less than 1 min. The electrodes were designed in an antiparallel configuration with 750 mu m width and 750 gm gap between them. The best results were recorded with a frequency of 400 kHz and 10 V-PP using a sinusoidal wave. The analytical performance of the proposed microchip was evaluated by electrophoretic separation of potassium, sodium and lithium in 150 mu m wide x 6 mu m deep microchannels. Under an electric field of 250 V/cm the analytes were successfully separated in less than 90 s with efficiencies ranging from 7000 to 13 000 plates. The detection limits (S/N = 3) found for K+, Na+, and Li+ were 3.1, 4.3, and 7.2 mu mol/L, respectively. Besides the low-cost and instrumental simplicity, the integrated PT chip eliminates the problem of manual alignment and gluing of the electrodes, permitting more robustness and better reproducibility, therefore, more suitable for mass production of electrophoresis microchips.

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A principal contribuição deste trabalho consiste na descoberta de uma evidência, na bolsa de valores de São Paulo, muito semelhante ao caso da Royal Dutch/Shell analisado por Froot e Dabora (1999): após o lançamento das ADRs por parte da Gerdau S.A, o desconto da Metalúrgica Gerdau em relação à Gerdau S.A passou a ser fortemente correlacionado tanto com a NYSE, quanto com a Bovespa, mesmo na presença do efeito tributário. Em outras palavras, após este divisor de águas, o preço relativo das duas empresas passou a ser afetado pelo local aonde elas são relativamente mais transacionadas, independentemente dos seus fundamentos.

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Esta dissertação aborda as relações de conflito interculturais no Assentamento Sino, conflitos que impedem uma relação de cooperação entre os assentados. Para o estudo desse tema dos conflitos foram analisadas diversas situações de conflito que emergiram da observação e das entrevistas realizadas no grupo em estudo. A escuta de cada trajetória de vida é fundamental para reconhecer as singularidades e as diferenças culturais, nas quais o conflito se torna um potencializador das relações entre o grupo e o mediador social que o integra. Essas relações de tensão são, na realidade, o lado positivo das tensões, que se tornam visíveis, viabilizando relações de cooperação. Destaco que o processo pedagógico presente neste estudo se pauta na não-intervenção, ou intervenção sob suspeita, aprendências que, tanto podem ser de interesse individual ou coletivo, primando pelas singularidades.

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Atualmente, os acidentes de trânsito têm se constituído como um grave problema sócio-econômico e de saúde pública, sendo responsáveis por 1,2 milhões de óbitos e 50 milhões de feridos por ano em todo mundo. Muitas são as causas que geram esses acidentes. O Brasil é tido como um dos líderes mundiais em acidentes de trânsito há mais de 30 anos. O custo desses acidentes de trânsito é muito elevado. Manaus, é uma cidade da Região Norte, considerada pólo regional, é uma das 49 aglomerações urbanas do país, e apresenta uma população de 1.688.524 habitantes aproximadamente. Como a maioria dos municípios brasileiros, o trânsito urbano é violento, vez que apresenta um alto índice de acidentes de trânsito. Durante os anos de 2007 e 2008, o Departamento Estadual de Trânsito do Amazonas(Detran/AM), colocou em funcionamento o programa educativo de prevenção de acidentes de trânsito denominado “Carona Solidária”, conhecido popularmente como “Disk Pileque”. Este trabalho consistiu em analisar as ações preventivas levadas a efeito durante os períodos carnavalescos de 2007 e 2008, com a execução do carona solidária, demonstrando sua efetividade na redução de acidentes de trânsito com vítimas fatais. A execução do programa se deu através do próprio Detran, que montou esquema no sentido de proporcionar melhor atendimento ao cidadão. Os dados foram obtidos através de relatórios emitidos pelo Detran/AM, de sorte que mostrassem as especificidades relacionadas aos acidentes. Os resultados mostraram que a execução do programa foi positiva, pois, o número de solicitações feitas superou as expectativas, gerando com isso redução de custos e principalmente redução da quantidade de vítimas fatais na cidade por ocasião dos períodos analisados.Foi sugerido que o programa seja executado em outros períodos do ano.

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O objetivo deste estudo busca identificar e descrever fatos indicadores da causa de descontinuidade do Banco Comércio e Indústria de são Paulo S.A. - COMIND. Aos 31 de dezembro de 1974, o COMIND assumira a posição do 6ª maior banco privado do país e, aos 19 de novembro de 1985, transformou-se na maior falência da história bancária brasileira. A descrição delineará o perfil da sua trajetória de existência, enfatizando o período da sua última gestão. Utilizando-se de documentação indireta, tais como relatórios de Comissão de Inquérito, de auditoria e de CPI da câmara, procurou-se a consistência das informações pertinentes ao caso em estudo. Os resultados obtidos propiciaram ordenar os fatos e proceder um cruzamento com causas de falências bancárias ocorridas, preponderantemente, nos E.U.A. As conclusões da pesquisa se basearam nas evidências resultantes de análise comparativa, culminando com o entendimento de que houve uma administração bancária frágil, inepta e centralizadora, além de omissão por parte da auditoria independente.

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Este trabalho se propõe a estudar uma das características que sempre faz parte da natureza de qualquer Universidade: sua autonomia. Esta prerrogativa não apenas tem sido reconhecida como necessária para a atuação de uma Universidade na história de cada sociedade, como também é considerada o sinal mais preciso da presença da "idéia" de Universidade em uma Instituição de Ensino Superior.

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Em amostra aleatória de trezentas e duas redações colhida na população de cem mil e trezentos candidatos que se submeteram ao vestibular da Fundação Cesgrario em janeiro de 1978. fez-se um estudo de vocabulário através da contagem dos substantivos adjetivos e verbos empregados. Foi analisada a relação entre o uso de substantivos, adjetivos e verbos diferentes: (como medida de riqueza vocabular (e o conceito obtido na medida de habilidade de expressão escrita).

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Studies on packaging accessibility are still incipient in Brazil. Many of these packagings can represent a challenge to users, whether due to non-informative labels, tricky tabs or seals, or even those that need strength to open. This paper brings a simple test to determine the necessary torque force to open PET bottles, and to predict the amount of users that could not open it. The findings suggest that a considerable amount of users could not open it or would have some difficulties to exert the necessary force.

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The speed and uniform germination of seeds, followed by the prompt seedling emergence, are highly desirable characteristics in seedling production. Studies aiming to enable the use of organic waste such as sewage sludge and pine bark in the supply chain represent a current demand. The aim of this study was to identify conditions of shading and substrate which are more favorable to the process of seed germination and seedling growth of Acacia mangium and Acacia mearnsii. After overcoming dormancy in hot water, the seeds were sown in three substrates: substrate plantmax commercial forest (control), pine bark and pine bark mixed with biosolids (1:1). The tubes were placed in a tree nursery under three shading conditions: 50%, 30% and 0% (full sun). The evaluated parameters were: speed and germination percentage (daily until 30 days) and shoot length of seedlings (weekly from 75 to 150 days). The experiment was a completely randomized design with treatments in a factorial 3 x 3 and the results were submitted to regression analysis. The highest germination was obtained in the sowing of Acacia mangium in pine bark at 30% shading and commercial substrate at 30 and 50% shading for Acacia mearnsii in pine bark under 50% shading or commercial substrate in full sun. For both species, seedlings grew faster and reached larger size in the final substrate of pine bark with biosolids and in any condition of shading (30 e 50 %) and full sun, anticipating the production of seedlings.

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In the North of Minas Gerais it is cultivated basically 'Prata-Ana' banana, a cultivar that requires mainly Zn. The possibility of zinc supply, without this nutrient getting in contact with the soil, it is important for the region, since several factors take to the low availability of the element supplied by the soil, as: elevated organic matter content on the surface (from cultural residues); maintenance of high pH of the soil - above 6,00 - as strategy contrary to the proliferation of the causal agent of the Fusarium Wilt; frequent fertilizations with potassium and magnesium that, besides converting the medium into base, they reduce the participation of Zn in the balance cation/anion of the soil, hindering the absortion of this micronutrient by the plant. For determining the distribution of biomass and minerals in the Prata-Ana" banana, cultivated under irrigation in the North of Minas Gerais, when the zinc was supplied through thinned sprout, an experiment was carried out in the Irrigated Perimeter of Jaiba. The plants were fertilized with 0,00; 1,66 and 3,33 g.family-(1) of Zn, through thinned sprout. One month after the fertilizations from October 2007 and February 2008, the production of fresh mass (FM) and dry mass (DM) were evaluated, the contents and meanings of minerals in all the bananas "family" bodies composed by mother-plant with bunch + tall daughter-plant + granddaughter-plant. The doses of Zn did not influence on the production of FM and DM of the plants in the first evaluation, while in the second evaluation positive effect of the treatment was observed just for MF accumulated in the inferior leaves, in the portions of the medium third and inferior of the pseudostem, and in the mother-plant's rhizome. As much the content as the accumulation of nutrients in the mother-plants presented the following decreasing order: K > N > Ca > Mg > P > S > Fe > Zn > B > Cu. The Zn contents were affected by the dose of that micronutrient in the most of the studied situations. The zinc supplied through thinned sprout increased in the mother-plant, and then it was redistributed in the banana's "family".

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The cellular and molecular characteristics of a cell line (BME26) derived from embryos of the cattle tick Rhipicephalus (Boophilus) microplus were studied. The cells contained glycogen inclusions, numerous mitochondria, and vesicles with heterogeneous electron densities dispersed throughout the cytoplasm. Vesicles contained lipids and sequestered palladium meso-porphyrin (Pd-mP) and rhodamine-hemoglobin, suggesting their involvement in the autophagic and endocytic pathways. The cells phagocytosed yeast and expressed genes encoding the antimicrobial peptides (microplusin and defensin). A cDNA library was made and 898 unique mRNA sequences were obtained. Among them, 556 sequences were not significantly similar to any sequence found in public databases. Annotation using Gene Ontology revealed transcripts related to several different functional classes. We identified transcripts involved in immune response such as ferritin, serine proteases, protease inhibitors,. antimicrobial peptides, heat shock protein, glutathione S-transferase, peroxidase, and NADPH oxidase. BME26 cells transfected with a plasmid carrying a red fluorescent protein reporter gene (DsRed2) transiently expressed DsRed2 for up to 5 weeks. We conclude that BME26 can be used to experimentally analyze diverse biological processes that occur in R. (B.) microplus such as the innate immune response to tick-borne pathogens. (C) 2008 Elsevier Ltd. All rights reserved.

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This work presents a theoretical, numerical and computation analysis of parameters of a rectangular microstrip antenna with metamaterial substrate, fin line as a coupler and also integrated devices like integrated filter antenna. It is applied theory to full-wave of Transverse Transmission Line - TTL method, to characterize the magnitude of the substrate and obtain the general equations of the electromagnetic fields. About the metamaterial, they are characterized by permittivity and permeability tensor, reaching to the general equations for the electromagnetic fields of the antenna. It is presented a study about main representation of PBG(Photonic Band Gap) material and its applied for a specific configuration. A few parameters are simulated some structures in order to reduce the physical dimensions and increase the bandwidth. The results are presented through graphs. The theoretical and computational analysis of this work have shown accurate and relatively concise. Conclusions are drawn and suggestions for future work

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In recent decades, changes have been occurring in the telecommunications industry, allied to competition driven by the policies of privatization and concessions, have fomented the world market irrefutably causing the emergence of a new reality. The reflections in Brazil have become evident due to the appearance of significant growth rates, getting in 2012 to provide a net operating income of 128 billion dollars, placing the country among the five major powers in the world in mobile communications. In this context, an issue of increasing importance to the financial health of companies is their ability to retain their customers, as well as turn them into loyal customers. The appearance of infidelity from customer operators has been generating monthly rates shutdowns about two to four percent per month accounting for business management one of its biggest challenges, since capturing a new customer has meant an expenditure greater than five times to retention. For this purpose, models have been developed by means of structural equation modeling to identify the relationships between the various determinants of customer loyalty in the context of services. The original contribution of this thesis is to develop a model for loyalty from the identification of relationships between determinants of satisfaction (latent variables) and the inclusion of attributes that determine the perceptions of service quality for the mobile communications industry, such as quality, satisfaction, value, trust, expectation and loyalty. It is a qualitative research which will be conducted with customers of operators through simple random sampling technique, using structured questionnaires. As a result, the proposed model and statistical evaluations should enable operators to conclude that customer loyalty is directly influenced by technical and operational quality of the services offered, as well as provide a satisfaction index for the mobile communication segment

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior