987 resultados para elikagaien zientzia eta teknologia
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A novel water soluble organometallic compound, [RuCp(mTPPMSNa)(2,2'-bipy)][CF3SO3] (TM85, where Cp=eta(5)-cyclopentadienyl, mTPPMS = diphenylphosphane-benzene-3-sulfonate and 2,2'-bipy = 2,2'-bipyridine) is presented herein. Studies of interactions with relevant proteins were performed to understand the behavior and mode of action of this complex in the biological environment. Electrochemical and fluorescence studies showed that TM85 strongly binds to albumin. Studies carried out to study the formation of TM85 which adducts with ubiquitin and cytochrome c were performed by electrospray ionization mass spectrometry (ESI-MS). Antitumor activity was evaluated against a variety of human cancer cell lines, namely A2780, A2780cisR, MCF7, MDAMB231, HT29, PC3 and V79 non-tumorigenic cells and compared with the reference drug cisplatin. TM85 cytotoxic effect was reduced in the presence of endocytosis modulators at low temperatures, suggesting an energy-dependent mechanism consistent with endocytosis. Ultrastructural analysis by transmission electron microscopy (TEM) revealed that TM85 targets the endomembranar system disrupting the Golgi and also affects the mitochondria. Disruption of plasma membrane observed by flow cytometry could lead to cellular damage and cell death. On the whole, the biological activity evaluated herein combined with the water solubility property suggests that complex TM85 could be a promising anticancer agent. (C) 2013 Elsevier Inc. All rights reserved.
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We present the modeling efforts on antenna design and frequency selection to monitor brain temperature during prolonged surgery using noninvasive microwave radiometry. A tapered log-spiral antenna design is chosen for its wideband characteristics that allow higher power collection from deep brain. Parametric analysis with the software HFSS is used to optimize antenna performance for deep brain temperature sensing. Radiometric antenna efficiency (eta) is evaluated in terms of the ratio of power collected from brain to total power received by the antenna. Anatomical information extracted from several adult computed tomography scans is used to establish design parameters for constructing an accurate layered 3-D tissue phantom. This head phantom includes separate brain and scalp regions, with tissue equivalent liquids circulating at independent temperatures on either side of an intact skull. The optimized frequency band is 1.1-1.6 GHz producing an average antenna efficiency of 50.3% from a two turn log-spiral antenna. The entire sensor package is contained in a lightweight and low-profile 2.8 cm diameter by 1.5 cm high assembly that can be held in place over the skin with an electromagnetic interference shielding adhesive patch. The calculated radiometric equivalent brain temperature tracks within 0.4 degrees C of the measured brain phantom temperature when the brain phantom is lowered 10. C and then returned to the original temperature (37 degrees C) over a 4.6-h experiment. The numerical and experimental results demonstrate that the optimized 2.5-cm log-spiral antenna is well suited for the noninvasive radiometric sensing of deep brain temperature.
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Molybdenum and tungsten complexes containing the pypzH (3-(2-pyridyl)pyrazole) ligand as a chelating bidentate are prepared: [Mo(CO)(4)(pypzH)], cis-[MoBr(eta(3)-allyl)(CO)(2)(pypzH)], cis-[MoCl(eta(3)-methallyl)(CO)(2)(pypzH)], [MI2(CO)(3)(pypzH)] (M = Mo, W) from [Mo(CO)(4)(NBD)] or the adequate bis(acetonitrile) complexes. The deprotonation of the molybdenum allyl or methallyl complexes affords the bimetallic complexes [cis-{Mo(eta(3)-allyl)(CO)(2)(mu(2)-pypz)}](2) or [cis-{Mo(eta(3)-methallyl)(CO)(2)(mu(2)-pypz)}](2) (mu(2)-pypz = mu(2)-3-(2-pyridyl-kappa N-1) pyrazolate-2 kappa N-1). The allyl complex was subjected to an electrochemical study, which shows a marked connection between both metallic centres through the bridging pyridylpyrazolates.
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New cationic ruthenium(II) complexes with the formula [Ru(eta(5)-C5H5)(LL)(1-BuIm)] [Z], with (LL) = 2PPh(3) or DPPE, and Z = CF3SO3-, PF6-, BPh4-, have been synthesized and fully characterized. Spectroscopic and electrochemical studies revealed that the electronic properties of the coordinated 1-butylimidazole were clearly influenced by the nature of the phosphane coligands (LL) and also by the different counter ions. The solid state structures of the six complexes determined by X-ray crystallographic studies, confirmed the expected distorted three-legged piano stool structure. However the geometry of the 1-butylimidazole ligand was found considerably different in all six compounds, being governed by the stereochemistry of the mono and bidentate coligands (PPh3 or DPPE).
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A new family of "RuCp" (Cp=eta(5)-C5H5) derivatives with bidentate N,O and N,N'-heteroaromatic ligands revealed outstanding cytotoxic properties against several human cell lines namely, A2780, A2780CisR, HT29, MCF7, MDAMB231, and PD. IC50 values were much lower than those found for cisplatin. Crystal structure of compound 4 was determined by X-ray diffraction studies. Density functional theory (DFT) calculations performed for compound 1 showed electronic flow from the ruthenium center to the coordinated bidentate ligand, in agreement with the electrochemical studies and the existence of a metal-to-ligand charge-transfer (MLCT) band evidenced by spectroscopic data.
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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica
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Introdução – A cintigrafia de perfusão do miocárdio (CPM) desempenha um importante papel no diagnóstico, avaliação e seguimento de pacientes com doença arterial coronária, sendo o seu processamento realizado maioritariamente de forma semiautomática. Uma vez que o desempenho dos técnicos de medicina nuclear (TMN) pode ser afetado por fatores individuais e ambientais, diferentes profissionais que processem os mesmos dados poderão obter diferentes estimativas dos parâmetros quantitativos (PQ). Objetivo – Avaliar a influência da experiência profissional e da função visual no processamento semiautomático da CPM. Analisar a variabilidade intra e interoperador na determinação dos PQ funcionais e de perfusão. Metodologia – Selecionou-se uma amostra de 20 TMN divididos em dois grupos, de acordo com a sua experiência no software Quantitative Gated SPECTTM: Grupo A (GA) – TMN ≥600h de experiência e Grupo B (GB) – TMN sem experiência. Submeteram-se os TMN a uma avaliação ortóptica e ao processamento de 21 CPM, cinco vezes, não consecutivas. Considerou-se uma visão alterada quando pelo menos um parâmetro da função visual se encontrava anormal. Para avaliar a repetibilidade e a reprodutibilidade recorreu-se à determinação dos coeficientes de variação, %. Na comparação dos PQ entre operadores, e para a análise do desempenho entre o GA e GB, aplicou-se o Teste de Friedman e de Wilcoxon, respetivamente, considerando o processamento das mesmas CPM. Para a comparação de TMN com visão normal e alterada na determinação dos PQ utilizou-se o Teste Mann-Whitney e para avaliar a influência da visão para cada PQ recorreu-se ao coeficiente de associação ETA. Diferenças estatisticamente significativas foram assumidas ao nível de significância de 5%. Resultados e Discussão – Verificou-se uma reduzida variabilidade intra (<6,59%) e inter (<5,07%) operador. O GB demonstrou ser o mais discrepante na determinação dos PQ, sendo a parede septal (PS) o único PQ que apresentou diferenças estatisticamente significativas (zw=-2,051, p=0,040), em detrimento do GA. No que se refere à influência da função visual foram detetadas diferenças estatisticamente significativas apenas na fração de ejeção do ventrículo esquerdo (FEVE) (U=11,5, p=0,012) entre TMN com visão normal e alterada, contribuindo a visão em 33,99% para a sua variação. Denotaram-se mais diferenças nos PQ obtidos em TMN que apresentam uma maior incidência de sintomatologia ocular e uma visão binocular diminuída. A FEVE demonstrou ser o parâmetro mais consistente entre operadores (1,86%). Conclusão – A CPM apresenta-se como uma técnica repetível e reprodutível, independente do operador. Verificou-se influência da experiência profissional e da função visual no processamento semiautomático da CPM, nos PQ PS e FEVE, respetivamente.
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A new family of eight ruthenium(II)-cyclopentadienyl bipyridine derivatives, bearing nitrogen, sulfur, phosphorous and carbonyl sigma bonded coligands, has been synthesized. Compounds bearing nitrogen bonded coligands were found to be unstable in aqueous solution, while the others presented appropriate stabilities for the biologic assays and pursued for determination of IC50 values in ovarian (A2780) and breast (MCF7 and MDAMB231) human cancer cell lines. These studies were also carried out for the [5: HSA] and [6: HSA] adducts (HSA = human serum albumin) and a better performance was found for the first case. Spectroscopic, electrochemical studies by cyclic voltammetry and density functional theory calculations allowed us to get some understanding on the electronic flow directions within the molecules and to find a possible clue concerning the structural features of coligands that can activate bipyridyl ligands toward an increased cytotoxic effect. X-ray structure analysis of compound [Ru(eta(5)-C5H5)(bipy)(PPh3)][PF6] (7; bipy = bipyridine) showed crystallization on C2/c space group with two enantiomers of the [Ru(eta(5)-C5H5)(bipy)(PPh3)](+) cation complex in the racemic crystal packing. (C) 2015 Elsevier Inc All rights reserved.
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A correlation and predictive scheme for the viscosity and self-diffusivity of liquid dialkyl adipates is presented. The scheme is based on the kinetic theory for dense hard-sphere fluids, applied to the van der Waals model of a liquid to predict the transport properties. A "universal" curve for a dimensionless viscosity of dialkyl adipates was obtained using recently published experimental viscosity and density data of compressed liquid dimethyl (DMA), dipropyl (DPA), and dibutyl (DBA) adipates. The experimental data are described by the correlation scheme with a root-mean-square deviation of +/- 0.34 %. The parameters describing the temperature dependence of the characteristic volume, V-0, and the roughness parameter, R-eta, for each adipate are well correlated with one single molecular parameter. Recently published experimental self-diffusion coefficients of the same set of liquid dialkyl adipates at atmospheric pressure were correlated using the characteristic volumes obtained from the viscosity data. The roughness factors, R-D, are well correlated with the same single molecular parameter found for viscosity. The root-mean-square deviation of the data from the correlation is less than 1.07 %. Tests are presented in order to assess the capability of the correlation scheme to estimate the viscosity of compressed liquid diethyl adipate (DEA) in a range of temperatures and pressures by comparison with literature data and of its self-diffusivity at atmospheric pressure in a range of temperatures. It is noteworthy that no data for DEA were used to build the correlation scheme. The deviations encountered between predicted and experimental data for the viscosity and self-diffusivity do not exceed 2.0 % and 2.2 %, respectively, which are commensurate with the estimated experimental measurement uncertainty, in both cases.
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Dissertação para obtenção do Grau de Mestre em Energia e Bioenergia
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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente – Perfil Engenharia Sanitária
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El texto considera que el espacio de la ciudad es representado hoy a partir de los mecanismos de construcción cultural del paisaje. Se concluye que estos tienen por consecuencia una fragmentación y una idealización/estilización del territorio. Al mismo tiempo que afirman el deleite estético y la idealización de la vida, los mecanismos referidos fomentan el abandono de una mirada crítica y global sobre la ciudad.
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Os sistemas de tratamento de água, existentes e de futuro, deverão ter em consideração diversos aspectos multidisciplinares, tais como o fenómeno de sobrepopulação, a escassez de água, a deterioração da qualidade das águas superficiais, o aumento das exigências legais e o aumento dos custos de energia. Neste sentido, os processos de separação por membranas (PSM), foram estudados para aferir acerca da sua aplicação na produção de água de elevada qualidade para consumo humano, independentemente das variações de qualidade na origem. Neste trabalho avaliou-se a qualidade da água da Albufeira de Monte Novo, concluindo-se que esta se encontra eutrofizada e com parâmetros indicadores da qualidade da água classificados com nível >A3. A linha de tratamento convencional, instalada na ETA de Monte Novo, foi avaliada perante um cenário de deterioração da qualidade da água bruta e de novos objectivos definidos para a qualidade final da água tratada. Sem a existência de uma nova etapa final de afinação, não é garantida a completa remoção de parâmetros microbiológicos (microrganismos potencialmente patogénicos, vírus, cianotoxinas) e de subprodutos da desinfecção. Foi proposta uma solução de reabilitação da linha de tratamento, que inclui um processo integrado de UF, complementado pela linha de tratamento existente, que actua como pré-tratamento. Esta solução foi analisada em termos de custos operacionais, comparativamente à solução actualmente instalada. Em comparação, o consumo energético anual da solução ETA-UF, tanto em época baixa, como em época alta, foi mais elevado, e o consumo de reagentes foi mais reduzido. Globalmente, a poupança obtida através das menores dosagens de reagentes, permitiu à solução ETA-UF diluir o efeito de um maior consumo energético, obtendo-se uma redução de 11% nos custos anuais operacionais e um custo de 0,08 €/m3 de água tratada. Tendo em conta o elevado investimento inicial na solução ETA-UF, o período de retorno foi de 6 anos, para um horizonte de projecto de 16 anos.
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ABSTRACT: Despite the reduction in deforestation rate in recent years, the impact of global warming by itself can cause changes in vegetation cover. The objective of this work was to investigate the possible changes on the major Brazilian biome, the Amazon Rainforest, under different climate change scenarios. The dynamic vegetation models may simulate changes in vegetation distribution and the biogeochemical processes due to climate change. Initially, the Inland dynamic vegetation model was forced with initial and boundary conditions provided by CFSR and the Eta regional climate model driven by the historical simulation of HadGEM2-ES. These simulations were validated using the Santarém tower data. In the second part, we assess the impact of a future climate change on the Amazon biome by applying the Inland model forced with regional climate change projections. The projections show that some areas of rainforest in the Amazon region are replaced by deciduous forest type and grassland in RCP4.5 scenario and only by grassland in RCP8.5 scenario at the end of this century. The model indicates a reduction of approximately 9% in the area of tropical forest in RCP4.5 scenario and a further reduction in the RCP8.5 scenario of about 50% in the eastern region of Amazon. Although the increase of CO2 atmospheric concentration may favour the growth of trees, the projections of Eta-HadGEM2-ES show increase of temperature and reduction of rainfall in the Amazon region, which caused the forest degradation in these simulations.
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OBJECTIVE: Studies conducted mainly in countries located in the Northern Hemisphere have shown that season of birth influences mood seasonality. Greater mood seasonality has been observed for individuals born during spring/summer months than those born during autumn/winter months. Expanding past research to the Southern Hemisphere, in this study we examine the influence of season of birth on mood seasonality in a sample of 1,247 healthy young Brazilians. METHOD: The Seasonal Pattern Assessment Questionnaire was used to compute a global seasonality score as a measure of mood seasonality in a cross-sectional study. RESULTS: Analysis of covariance was conducted to examine the effects of month of birth and gender on mood seasonality, with age entered as a covariate. A main effect of gender was observed, F (1, 1197) = 17.86, p < .01; partial Eta-squared = .02, with mood seasonality being higher for females (M = 8) than for males (M = 7). Contradicting previous findings, no significant main effect for month of birth was observed, F (1, 1197) = 0.65, p > .05. CONCLUSION: The unexpected finding is tentatively explained by differences in geographic location and weather fluctuations between the sampling location in Brazil and other countries where season of birth has been found to influence mood seasonality. Additional studies with larger samples from the Southern Hemisphere are necessary to shed additional light on the possible significant influence of season of birth on mood.