1000 resultados para 157-953A
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Fundação para a Ciência e a Tecnologia (FCT), Fundação Millennium bcp, Imprensa Nacional-Casa da Moeda
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In this work we present semi-analytical solutions for the electro-osmotic annular flow of viscoelastic fluids modeled by the Linear and Exponential PTT models. The viscoelastic fluid flows in the axial direction between two concentric cylinders under the combined influences of electrokinetic and pressure forcings. The analysis invokes the Debye-Hückel approximation and includes the limit case of pure electro-osmotic flow. The solution is valid for both no slip and slip velocity at the walls and the chosen slip boundary condition is the linear Navier slip velocity model. The combined effects of fluid rheology, electro-osmotic and pressure gradient forcings on the fluid velocity distribution are also discussed.
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Stress/strain sensors constitute a class of devices with a global ever-growing market thanks to their use in many fields of modern life. They are typically constituted by thin metal foils deposited on flexible supports. However, the low inherent resistivity and limited flexibility of their constituents make them inadequate for several applications, such as measuring large movements in robotic systems and biological tissues. As an alternative to the traditional compounds, in the present work we will show the advantages to employ a smart material, polyaniline (PANI), prepared by an innovative environmentally friendly route, for force/strain sensor applications wherein simple processing, environmental friendliness and sensitivity are particularly required.
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A search for high-mass resonances decaying into τ+τ− final states using proton-proton collisions at s√=8 TeV produced by the Large Hadron Collider is presented. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 19.5-20.3 fb−1. No statistically significant excess above the Standard Model expectation is observed; 95% credibility upper limits are set on the cross section times branching fraction of Z′ resonances decaying into τ+τ− pairs as a function of the resonance mass. As a result, Z′ bosons of the Sequential Standard Model with masses less than 2.02 TeV are excluded at 95% credibility. The impact of the fermionic couplings on the Z′ acceptance is investigated and limits are also placed on a Z′ model that exhibits enhanced couplings to third-generation fermions.
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Avaliou-se a fitossociologia de floresta manejada em lotes de comunitários da Comunidade Santo Antônio no Assentamento Moju I e II, município de Santarém, Amazônia brasileira. Foram instaladas 12 parcelas de 50 m x 200 m (1 por lote) anotando-se indivíduos com CAP ≥ 157,1 cm (nível 3 de inclusão); 12 sub-parcelas de 50 m x 50 m, para os indivíduos com 94,2 cm ≤ CAP < 157,1 cm (nível 2 de inclusão) e 12 sub-parcelas de 50 m x 25 m, para os indivíduos com 31,4cm ≤ CAP < 94,2 cm (nível 1 de inclusão). Foram amostrados 1.227 indivíduos, distribuídos em 175 espécies e 38 famílias botânicas. A família Fabaceae apresentou maior número de espécies e o gênero mais rico foi Inga. O Índice de Diversidade de Shannon (H') foi 4,39 e o Índice de Equabilidade de Pielou (J) de 0,85. A avaliação do Valor de Importância Ampliado (VIA) das espécies da amostra revelou o estoque de espécies com potencial madeireiro e não madeireiro. Carapa guianensis, Caryocar villosum, Brosimum parinarioides, Aniba canellila, Bowdichia virgilioides e Andira surinamensis podem ser aproveitadas como produtos florestais não madeireiros e serem removidas da lista de espécies de corte para fins madeireiros, melhorando assim o retorno econômico comunitário. Manilkara huberi e Carapa guianensis foram espécies com utilização madeireira e não madeireira mais expressivas, considerando o mercado atual e potencial de usos conhecidos; portanto, tais características devem ser consideradas no planejamento e execução do manejo da floresta.
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First records of myxomycetes in the North region of Brazil go back to the 19th century. Nevertheless, the myxobiota of this region is still largely unexplored, with only 42 species recorded, distributed in 20 genera and seven families. The objectives of this paper were to characterize the Myxomycetes collection of the Herbarium of the Federal University of Roraima (UFRR) and to add new records for the myxobiota of this State. The collection holds specimens collected in fragments of Open Ombrophilous Forest, Seasonal Semi-deciduous Forest, Riparian Forest, deforested areas and urban home gardens in the state of Roraima. The 157 exsiccates were analyzed and identified or redetermined based on identification keys, descriptions and illustrations. The collection is in good conditions of preservation and includes all subclasses of Myxomycetes, 83% of its orders, 50% of its families, and 20 species. Trichiales, with one family, three genera and six species, represents 62% of all exsiccates. Cribraria aff. splendens, Metatrichia vesparia, Physarella oblonga, Stemonaria longa and Stemonitis splendens are new records for Roraima and Arcyria obvelata, Comatricha pulchella, Stemonitis pallida and Stemonitopsis aequalis are referred for the first time in the Northern Region, enlarging the knowledge of the Brazilian geographic distribution of these species.
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O presente artigo apresenta o enredo de um projeto de investigação de doutoramento em Ciências da Educação, especialidade Tecnologia Educativa, que vem trabalhar a questão da democratização das TIC ao saber docente. nesta perspectiva, traz a compreensão de que o distanciamento entre as iniciativas de integração da Tecnologia educativa ao saber docente, reúne questões de ordem social, política e econômica. Dado o fundamento, busca implementar um curso de formação continuada que possa trazer essa tecnologia educativa ao conhecimento do professor, levando-o para uma reflexão do processo formativo como fenómeno de integração das práticas pedagógicas à Sociedade da Informação e Conhecimento.
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Aiming at biosignal acquisition for bioelectrodes application, Ti-Ag thin films were produced by GLAD, in order to tailor their electromechanical properties. The electrical behaviour of the sculptured Ti-Ag thin films was studied with increasing annealing temperatures. The results revealed a good correlation with the set of morphological features displayed. With the increase of the vapour flux angle, a more defined structure was obtained, as well as a more porous morphology, which increased the electrical resistivity of the coatings. An important point consists in the recrystallization of Ti-Ag intermetallic phases due to the temperature increase (between 558 K and 773 K), which resulted in a sharp decrease of the electrical resistivity values.
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Acetate is a short-chain fatty acid secreted by Propionibacteria from the human intestine, known to induce mitochondrial apoptotic death in colorectal cancer (CRC) cells. We previously established that acetate also induces lysosome membrane permeabilization in CRC cells, associated with release of the lysosomal protease cathepsin D (CatD), which has a well-established role in the mitochondrial apoptotic cascade. Unexpectedly, we showed that CatD has an antiapoptotic role in this process, as pepstatin A (a CatD inhibitor) increased acetate-induced apoptosis. These results mimicked our previous data in the yeast system showing that acetic acid activates a mitochondria-dependent apoptosis process associated with vacuolar membrane permeabilization and release of the vacuolar protease Pep4p, ortholog of mammalian CatD. Indeed, this protease was required for cell survival in a manner dependent on its catalytic activity and for efficient mitochondrial degradation independently of autophagy. In this study, we therefore assessed the role of CatD in acetate-induced mitochondrial alterations. We found that, similar to acetic acid in yeast, acetate-induced apoptosis is not associated with autophagy induction in CRC cells. Moreover, inhibition of CatD with small interfering RNA or pepstatin A enhanced apoptosis associated with higher mitochondrial dysfunction and increased mitochondrial mass. This effect seems to be specific, as inhibition of CatB and CatL with E-64d had no effect, nor were these proteases significantly released to the cytosol during acetate-induced apoptosis. Using yeast cells, we further show that the role of Pep4p in mitochondrial degradation depends on its protease activity and is complemented by CatD, indicating that this mechanism is conserved. In summary, the clues provided by the yeast model unveiled a novel CatD function in the degradation of damaged mitochondria when autophagy is impaired, which protects CRC cells from acetate-induced apoptosis. CatD inhibitors could therefore enhance acetate-mediated cancer cell death, presenting a novel strategy for prevention or therapy of CRC.
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OBJETIVO: Estudo multicêntrico, aberto e não comparativo, para avaliar a eficácia e a tolerabilidade de dois agentes anti-hipertensivos combinados em doses baixas: o beta-bloqueador cardiosseletivo bisoprolol (2,5 e 5,0mg) com 6,25mg de hidroclorotiazida. MÉTODOS: Cento e seis pacientes com hipertensão arterial nos estágios I e II (leve a moderada) receberam a combinação bisoprolol/hidroclorotiazida, em uma única dose diária, e foram submetidos a uma avaliação da pressão arterial sistólica (PAS) e pressão arterial diastólica (PAD), durante 8 semanas. RESULTADOS: A combinação bisoprolol/hidroclorotiazida reduziu significativamente os valores médios iniciais da PAS (157,4mmHg para 137,3mmHg) e da PAD (98,8mmHg para 87,4mmHg). Ao final do estudo, 61% haviam normalizado a PA (<90mmHg) e 22,9% deles foram responsivos ao tratamento, resultando em elevada taxa de resposta terapêutica (normalizados + responsivos) - total de 83.9% dos casos. Eventos adversos foram descritos em 18,9% dos pacientes, sendo os mais freqüentes: tontura e cefaléia. Não se observaram alterações clinicamente significativas nos níveis plasmáticos de glicose, potássio, ácido úrico e perfil lipídico. CONCLUSÃO: A combinação bisoprolol/hidroclorotiazida em baixas doses pode ser considerada uma alternativa racional, eficaz e bem tolerada para o tratamento inicial da hipertensão arterial leve ou moderada.
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Risk management is of paramount importance in the success of tunnelling works and is linked to the tunnelling method and to the constraints of the works. Sequencial Excavation Method (SEM) and Tun-nel Boring Machine (TBM) method have been competing for years. This article, part of a wider study on the influence of the â Safety and Healthâ criterion in the choice of method, reviews the existing literature about the criteria usually employed to choose the tunnelling method and on the criterion â Safety and Healthâ . This crite-rion is particularly important, due to the financial impacts of work accidents and occupational diseases. This article is especially useful to the scientific and technical community, since it synthesizes the relevance of each one of the choice criteria used and it shows why â Safety and Healthâ must be a criterion in the decision mak-ing process to choose the tunnelling method.
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OBJECTIVE: To compare sleepiness scores of the Epworth scale in patients with different levels of arterial pressure when undergoing outpatient monitoring within the context of clinical evaluation. METHODS: A total of 157 patients selected for outpatient monitoring of arterial pressure during hypertension evaluation were divided into 3 groups: group 1 - normotensive; group 2 - hypertensive; group 3 - resistant hypertensive. For analysis, values > or = 11 were considered as associated with respiratory disturbances during sleep. RESULTS: Seventeen (10.8%) patients in group 1, 112 (71.3%) in group 2, and 28 (17.8%) in group 3, which was composed of aged, more severely hypertensive individuals, were analyzed. Groups were similar relative to sex and body mass index, but different in relation to systolic and diastolic pressure levels and age. Despite an absolute difference, no statistically significant difference occurred between Epworth scores and in the proportion of patients with values > or = 11 (5.9% vs. 18.8% vs. 212.4%; P=0.37). Despite the positive association between degree of sleepiness measured with the scale and the severity of the hypertension, no statistical significance occurred following control by age (p=0.18). CONCLUSION: A positive correlation exists between degree of sleepiness and hypertension severity. The absence of a statistical significance shown in the present study could be due to a beta type of error. Instruments that render this complaint into an objective finding could help in the pursuit of an investigation of respiratory disturbances during sleep in more severely hypertensive patients, and should therefore be studied better.
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OBJECTIVE: To report the frequency and types of electrocardiographic alterations in patients with leptospirosis in the first 24 hours of hospitalization. METHODS: We analyzed the electrocardiograms of 157 patients admitted to the Hospital Couto Maia in the city of Salvador, in the State of Bahia, Brazil, from March 1998 to June 1999. The electrocardiograms were performed in the first 24 hours after hospital admission, independent of the clinical manifestations of the patients. RESULTS: The mean ± SD for patients' age was 35.5± 13.7 (median = 32) years, and jaundice was present in 95.5% of them. Alterations in the electrocardiogram were detected in 68.2% (107/157) of the patients (95% confidence interval = 60.6% - 75.1%). Atrial fibrillation was the most frequent arrhythmia, occurring in 10.8% (17/157) of the patients. Other frequent findings were alterations in ventricular repolarization detected in 38.9% (61/157) of patients and first-degree atrioventricular block in 10.2% (16/157). The patients with atrial fibrillation were older and had higher levels of creatinine and aminotransferases. CONCLUSION: In this sample, approximately 2/3 of the patients had electrocardiographic alterations after hospital admission. Of the major arrhythmias, atrial fibrillation was the most frequent, and the patients with this arrhythmia had evidence of more severe disease. The relation between the presence and type of electrocardiographic alteration and the prognosis of leptospirosis is yet to be assessed.
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La presencia de antimicrobianos en leche ocasiona una serie de trastornos en la salud humana, como inducción de alergias, resistencia bacteriana y a otro nivel, y pueden afectar los procesos de industrialización de la misma. Existen métodos de determinación de antibióticos cuantitativos y cualitativos, siendo los primeros los más apropiados por su exactitud aunque resulten más complejos y costosos. Entre los segundos se utilizan numerosas técnicas microbiológicas simples y económicas que garantizan determinaciones por debajo de los límites máximos de residuos fijados por distintos bloques comerciales. No obstante, al no cuantificar y por basarse en inhibiciones de crecimiento bacteriano resulta muy controvertida su utilización en la fijación de tiempos de retirada. Estudiaremos fármacos de dos grupos de antimicrobianos utilizados frecuentemente en la terapéutica actual en bovinos productores de leche, estos son los betalactámicos y los macrólidos. Para cada droga se realizarán determinaciones en leche de animales sanos y enfermos con métodos microbiológicos cuantitativos y cualitativos . Se determinarán los tiempos de retirada correspondientes y se compararán estadísticamente estableciendo las diferencias. Los resultados obtenidos en este proyecto plantearán una reformulación de los períodos de retirada que tendrán que fijar los laboratorios productores de medicamentos veterinarios, recomendar los profesionales veterinarios e industrias lácteas y respetar los productores lecheros.
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FUNDAMENTO: Devido à sobreposição de sintomas e inadequada capacidade de exercícios, o diagnóstico não-invasivo da doença arterial coronariana (DAC) pode ser sub ou superestimado em pacientes com doença pulmonar obstrutiva crônica (DPOC). OBJETIVO: Avaliar os resultados de angiografias coronarianas em pacientes com DPOC dependendo das características clínicas basais. MÉTODOS: Os registros médicos de 157 pacientes com DPOC e 157 pacientes sem DPOC pareados por características clínicas basais, que haviam sido submetidos a angiografia coronariana diagnóstica pela primeira vez, foram revisados, retrospectivamente. RESULTADOS: A frequência de DAC era significantemente mais baixa em pacientes com DPOC do que no grupo controle (52,8% vs. 80,2%, p<0,001). As frequências dos fatores de risco para DAC (idade avançada, hipertensão, diabete, histórico de fumo) eram significantemente mais comuns entre os pacientes com DPOC que tinham DAC significativa. Entre os pacientes que reportavam angina pectoris estável, DAC significativa foi detectada em 32,7% dos pacientes com DPOC e em 71,0% dos pacientes sem DPOC (p<0,001). Entretanto, para os pacientes com diagnóstico de angina pectoris instável, DAC significativa foi detectada em 87,5% dos pacientes com DPOC e 90,2% dos pacientes sem DPOC (p=0,755). CONCLUSÃO: O diagnóstico de DAC pacientes com DPOC através da sintomatologia, somente, pode ser difícil. Entretanto, o diagnóstico clínico de DAC no quadro de angina instável é acurado na maioria dos pacientes com DPOC. Assim, outros métodos diagnósticos não-invasivos ou seguimento cuidadoso podem ser mais apropriados para pacientes com DPOC que reportam angina pectoris estável.