941 resultados para Networked Digital Environment
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Objectivo: Avaliar a acuidade da angiografia de subtracção digital (ASD) no diagnóstico morfológico da conexão venosa pulmonar anómala (CVPA) em crianças. Concepção do estudo: Estudo prospectivo de doentes consecutivos entre Janeiro de 1989 e Julho de 1992. Tipo de Atendimento: Serviço de Cardiologia Pediátrica de um Hospital Central. População: Vinte e quatro doentes com CVPA. Métodos: Todos os doentes fizeram avaliação clínica e ecocardiográfica completa (modo M, bidimensional e Doppler) antes da realização do exame hemodinâmico. Em todos os casos se fizeram, de modo sistemático, injecções selectivas de contraste de baixa osmolaridade (0,5-1 ml/kg; dose total <6 mi/kg) no tronco e ramos da artéria pulmonar com registo em angiografia com subtracção digital (ASD). As imagens colhidas foram trabalhadas, selecciona das e armazenadas em video-cassetes e películas fotográficas (câmara multiformato). Resultados: Dezasseis doentes tinham CVPA total (CVPAT): onze à veia cava superior (VCS), dois ao seio coronário e três infradiafragmáticos (dois à veia cava inferior (VCI) e um à veia porta). Oito crianças tinham CVPA parcial (CVPAP): três à VCS, uma à aurícula direita (AD), três à VCI (síndroma da cimitarra) e num caso a CVPA era mista. Em oito doentes (seis com CVPAT e dois com CVPAP), a ASD contribuiu significativamente para o diagnóstico final tendo completado ou corrigido a informação obtida por ecocardiografia. Nos dezoito doentes submetidos a cirurgia cardíaca foi confirmado o diagnóstico obtido por ASD. Conclusões: A ASD é um método muito útil para o diagnóstico anatómico de doentes com CVPA. Na nossa experiência foi particularmente informativa a análise de registos em «video». A ASD está indicada nos casos em que os achados clínicos e ecocardiográficos não sejam típicos.
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Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica e de Computadores
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Relatório para obtenção do Grau de Mestre em Ensino da Física e da Química
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Currently multiresistant Staphylococcus aureus is one common cause of infections with high rates of morbidity and mortality worldwide, which directs scientific endeavors in search for novel antimicrobials. In this study, nine extracts from Bidens pilosa (root, stem, flower and leaves) and Annona crassiflora (rind fruit, stem, leaves, seed and pulp) were obtained with ethanol: water (7:3, v/v) and their in vitro antibacterial activity evaluated through both the agar diffusion and broth microdilution methods against 60 Oxacillin Resistant S. aureus (ORSA) strains and against S. aureus ATCC6538. The extracts from B. pilosa and A. crassiflora inhibited the growth of the ORSA isolates in both methods. Leaves of B. pilosa presented mean of the inhibition zone diameters significantly higher than chlorexidine 0.12% against ORSA, and the extracts were more active against S. aureus ATCC (p < 0.05). Parallel, toxicity testing by using MTT method and phytochemical screening were assessed, and three extracts (B. pilosa, root and leaf, and A. crassiflora, seed) did not evidence toxicity. On the other hand, the cytotoxic concentrations (CC50 and CC90) for other extracts ranged from 2.06 to 10.77 mg/mL. The presence of variable alkaloids, flavonoids, tannins and saponins was observed, even though there was a total absence of anthraquinones. Thus, the extracts from the leaves of B. pilosa revealed good anti-ORSA activity and did not exhibit toxicity.
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Ligand K-edge XAS of an [Fe3S4]0 model complex is reported. The pre-edge can be resolved into contributions from the í2Ssulfide, í3Ssulfide, and Sthiolate ligands. The average ligand-metal bond covalencies obtained from these pre-edges are further distributed between Fe3+ and Fe2.5+ components using DFT calculations. The bridging ligand covalency in the [Fe2S2]+ subsite of the [Fe3S4]0 cluster is found to be significantly lower than its value in a reduced [Fe2S2] cluster (38% vs 61%, respectively). This lowered bridging ligand covalency reduces the superexchange coupling parameter J relative to its value in a reduced [Fe2S2]+ site (-146 cm-1 vs -360 cm-1, respectively). This decrease in J, along with estimates of the double exchange parameter B and vibronic coupling parameter ì2/k-, leads to an S ) 2 delocalized ground state in the [Fe3S4]0 cluster. The S K-edge XAS of the protein ferredoxin II (Fd II) from the D. gigas active site shows a decrease in covalency compared to the model complex, in the same oxidation state, which correlates with the number of H-bonding interactions to specific sulfur ligands present in the active site. The changes in ligand-metal bond covalencies upon redox compared with DFT calculations indicate that the redox reaction involves a two-electron change (one-electron ionization plus a spin change of a second electron) with significant electronic relaxation. The presence of the redox inactive Fe3+ center is found to decrease the barrier of the redox process in the [Fe3S4] cluster due to its strong antiferromagnetic coupling with the redox active Fe2S2 subsite.
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Os modelos a ser analisados pelo Método de Elementos Finitos são cada vez mais complexos e, nos tempos que correm, seria impensável realizar tais análises sem um apoio computorizado. Existe para esta finalidade uma vasta gama de programas que permitem realizar tarefas que passam pelo desenho de estruturas, análise estática de cargas, análise dinâmica e vibrações, visualização do comportamento físico (deformações) em tempo real, que permitem a otimização da estrutura. Sob o pretexto de permitir a qualquer utilizador uma análise de estruturas simples com o Método dos Elementos Finitos, surge esta tese, onde se irá criar de raiz um programa com interface gráfica no ambiente MATLAB® para análise de estruturas simples com dois tipos de elemento finito, triangular de deformação constante e quadrangular de deformação linear. O software desenvolvido, verificado por comparação com um software comercial dedicado para o efeito, efetua malhagem com elementos bidimensionais triangulares e quadriláteros e resolve modelos arbitrados pelo Método de Elementos Finitos, representando estes resultados visualmente e em formato tabular.
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Dissertação para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores
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Dermatophytosis is a common zoonosis in urban centers. Dogs and cats have played an important role as its disseminators. Environmental decontamination is essential for the prevention of its propagation to humans and animals. However, sanitizers or disinfectants with antifungal activity, currently available, have high toxicity. The present study evaluated the in vitro effects of an extract of citronella (Cymbopogon nardus) on 31 Microsporum canis isolates from animals and home environments. Susceptibility tests were performed based on document M38-A2 (2008) of the Clinical and Laboratory Standards Institute with modifications for natural products. Although susceptibility variation was observed between the fungus tested, the concentrations that inhibited the growth of 50 and 90% of the microorganisms were low (19.5 and 78 µg/mL, respectively). Thus, this citronella extract showed potent fungistatic and fungicide activities against M. canis isolated from animals and home environments. Therefore, it could be an alternative for dermatophytosis prophylaxis in the home environment.
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Dissertação para obtenção do Grau de Mestre em Engenharia Informática
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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em História da Arte Contemporânea
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Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão Industrial
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Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Computer Engineering of the Faculdade de Ciências e Tecnologia of Universidade Nova de Lisboa
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Background: Indoor air quality (IAQ) is considered an important determinant of human health. The association between exposure to volatile organic compounds, particulate matter, house dust mite, molds and bacteria in day care centers (DCC) is not completely clear. The aim of this project was to study these effects. Methods --- study design: This study comprised two phases. Phase I included an evaluation of 45 DCCs (25 from Lisbon and 20 from Oporto, targeting 5161 children). In this phase, building characteristics, indoor CO2 and air temperature/relative humidity, were assessed. A children’s respiratory health questionnaire derived from the ISAAC (International Study on Asthma and Allergies in Children) was also distributed. Phase II encompassed two evaluations and included 20 DCCs selected from phase I after a cluster analysis (11 from Lisbon and 9 from Oporto, targeting 2287 children). In this phase, data on ventilation, IAQ, thermal comfort parameters, respiratory and allergic health, airway inflammation biomarkers, respiratory virus infection patterns and parental and child stress were collected. Results: In Phase I, building characteristics, occupant behavior and ventilation surrogates were collected from all DCCs. The response rate of the questionnaire was 61.7% (3186 children). Phase II included 1221 children. Association results between DCC characteristics, IAQ and health outcomes will be provided in order to support recommendations on IAQ and children’s health. A building ventilation model will also be developed. Discussion: This paper outlines methods that might be implemented by other investigators conducting studies on the association between respiratory health and indoor air quality at DCC.
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação
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Relatório de Estágio apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ensino de Inglês e de Língua estrangeira (Francês) no 3º ciclo do ensino básico e secundário