959 resultados para membrane permeation of gases
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The central and western parts of the State of São Paulo are well-known for vast sugar cane plantations, which during the harvest time are traditionally burnt about 12 hours before manual cutting. This procedure causes the release of large quantities of aerosols and a variety of gases, which can be observed by IPMet's radars, located in Bauru and Presidente Prudente, on days with no or little rain. Depending on the distance of these plumes from the radar, they can be detected up to 5 km amsl or more, and are subsequently being transported by winds to other regions. During the dry winter season of 2008, such plumes, attributed to cane fires, were frequently observed by IPMet's radars and documented in terms of radar reflectivity, time and location during the period 10 th - 21 st July 2008. At the same time, IPEN's Elastic Backscatter Lidar in São Paulo observed layers of aerosols of variable strength and heights above the city. The most significant days, viz. 14 and 15 July 2008 had been selected for calculating backward, as well as forward trajectories, deploying the European Flextra 3.3 Trajectory Model, which was initiated with ECMWF historic data with a 0,25 o×0,25 o grid spacing. The results presented here show an excellent match between the radar-detected sources of the plumes on 11 th July 2008 in the central parts of the State and the observations by IPEN's Lidar over Metropolitan São Paulo on 14 th July 2008, both in terms of forward and backward trajectories, as well as their heights, with a transport duration of approximately 70 hours under the prevailing meteorological conditions. © Sociedad Española de Óptica.
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This study was aimed to verify if chicks from eggs injected with ascorbic acid and subjected to thermal stress would have higher immunity than chicks from incubation at thermoneutrality without injection of ascorbic acid. The parameters evaluated were temperature on oxygen saturation in hemoglobin, glucose, number of erythrocytes, hematocrit rate and number of hemoglobins of newly hatched male chicks, hatched from eggs injected with ascorbic acid (AA) and subjected to thermal stress during incubation. The experimental design was completely randomized in factorial scheme 5 (application levels of ascorbic acid) x 2 (incubation temperatures). The data were subjected to analysis of variance using the General Linear Model procedure (GLM) of SAS ®. For the parameters (number of erythrocytes, rate of hematrocit and values of hemoglobin), there was significant interaction (p <0.05) between treatments in egg and incubation temperatures. Analyzing the interactions for these parameters, it was observed that the application of 0% ascorbic acid in egg minimized the effect of heat stress when compared with treatment without injection. The application of ascorbic acid levels in eggs incubated under heat stress failed to maximize the immunity of newly hatched chicks. It is assumed that the increased liquid in the amniotic fluid, in those embryos injected with water, favored the lower heat conductance for these embryos, thus helping in their development in relation to immunity. Considering that hemoglobin is related to the transport of gases, these data suggest that increasing the concentration of AA solution inoculated may influence the respiratory rates of eggs.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Engenharia Mecânica - FEG
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A produção de alumina pelo processo Bayer produz de 1 a 3 toneladas de resíduo por tonelada de alumínio. Esse resíduo é denominado lama vermelha, composto de minerais não solúveis em hidróxido de sódio concentrado, como hematita e outros óxidos férreos, quartzo e óxidos de titânio. A lama vermelha possui em sua composição variados teores de NaOH, dependendo especificamente da planta industrial utilizada. A proposta desse trabalho é avaliar o processo de absorção de gases provenientes de uma caldeira em contracorrente com uma suspensão de lama vermelha a 27%, em torre spray e em torre de recheio estruturado. Foram realizados experimentos variando-se o tipo de torre de absorção, temperatura da fase líquida e teor de sólidos na fase líquida para avaliar a redução do teor dos gases de combustão na saída da torre de absorção e a variação do pH de acordo com o tempo de operação, para que fosse possível identificar o tempo necessário para que ocorra a neutralização da lama vermelha, bem como a redução no teor de dióxido de carbono, para isso foram realizadas medições dos teores de gases na entrada e na saída da torre de recheio estruturado, bem como medições de temperatura e pH. A absorção de CO2 presente no gás de combustão pela suspensão de lama vermelha se dá pelo processo da carbonatação, no qual o gás reage com o NaOH presente na lama vermelha, sendo a água o catalisador. Os resultados obtidos após os experimentos foram satisfatórios, e concluiu-se que o processo realizado nas torres de absorção é eficiente para a diminuição do pH da lama vermelha e a redução do teor de CO2 liberado para a atmosfera, promovendo um ganho duplo para o meio ambiente.
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ABSTRACT: Paroxysmal nocturnal hemoglobinuria is a hematological disease with complex physiopathology. It is genetically characterized by a somatic mutation in the PIG-A gene (phosphatidylinositol glycan anchor biosynthesis, class A), in which the best known antigens are DAF (decay accelerating factor or CD55) and MIRL (membrane inhibitor of reactive lysis or CD59). OBJECTIVE: To determine the frequency of paroxysmal nocturnal hemoglobinuria in patients attended at the HEMOPA foundation from November 2008 to July 2009. METHOD: Thirty patients, with ages ranging from two to 79 years old and suspected of having paroxysmal nocturnal hemoglobinuria were examined. All patients were immunophenotyped by flow cytometry for the CD5, CD59, CD16 and CD45 antigens. RESULTS: Paroxysmal nocturnal hemoglobinuria was identified in nine of the thirty patients investigated. Another 3 cases had inconclusive results with CD59-negative labeling only for neutrophils. The highest frequency of paroxysmal nocturnal hemoglobinuria patients (7/9) and inconclusive cases (2/3) were between 19 years old and 48 years old, with a median of 28 years. CONCLUSION: These results show the importance of flow cytometry to identify cases in which patients are deficient in only one antigen (CD59).
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Pós-graduação em Zootecnia - FCAV
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Background: Soft tissue sarcomas (STSs) are a group of neoplasms, which, despite current therapeutic advances, still confer a poor outcome to half of the patients. As other solid tumors, STSs exhibit high glucose consumption rates, associated with worse prognosis and therapeutic response. As highly glycolytic tumors, we hypothesized that sarcomas should present an increased expression of lactate transporters (MCTs).Methods: Immunohistochemical expression of MCT1, MCT2, MCT4 and CD147 was assessed in a series of 86 STSs and the expression profiles were associated with patients' clinical-pathological parameters.Results: MCT1, MCT4 and CD147 were mainly observed in the plasma membrane of cancer cells (around 60% for MCTs and 40% for CD147), while MCT2 was conspicuously found in the cytoplasm (94.2%). Importantly, we observed MCT1 nuclear expression (32.6%). MCT1 and MCT4, alone or co-expressed with CD147 in the plasma membrane, were associated with poor prognostic variables including high tumor grade, disease progression and shorter overall survival. Conversely, we found MCT1 nuclear expression to be associated with low grade tumors and longer overall survival.Conclusions: The present work represents the first report of MCTs characterization in STSs. We showed the original finding of MCT1 expression in the nucleus. Importantly, opposite biological roles should be behind the dual sub-cellular localization of MCT1, as plasma membrane expression of MCT1 is associated with worse patients' prognosis, while nuclear expression is associated with better prognosis.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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In materials science, the search for technological improvements have become one of the main subject of study of researchers. This is especially true in the case of materials with reduced sizes, in the nanometer scale. Important phenomena to be studied in these cases are the desorption and adsorption on two-dimensional materials, such as graphene. These phenomena are of great importance in the study of interactions between organic films, synthesis or catalysis of reactions on surfaces and even in the creation of nanoscale devices [1, 2, 3, 4]. Between the most important topics related to these phenomena are the storage of gases in low-dimensional systems and the study of nanostructured fuel cells or batteries. In this context we used two different parametrizations for the reactive force field ReaxFF to study the potential barriers and reaction barriers of our system. First we made a study about the Reaction Barriers and Energy Barriers for bonds between graphene and the following atoms: sulfur, fluorine, hydrogen, nitrogen and oxygen. It is important to have this information in order to make it possible to understand how these atoms react with the graphene sheet. Subsequently, we calculate reaction barriers for mixed structures where fluorine is a fixed element bonded to graphene and other element is simultaneously bonded to graphene. This other element (N, O, H or S) is varied in its possible relative positions (ortho, meta and para in relation to fluorine in either: the same side and in the opposite side of the graphene membrane)
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The importance of this study is based on the need to obtain simple and efficient in vitro models to predict the in vivo toxicity of cosmetics, aiming not to use animals as experimental model. Here, we proposed the use of HepG2 cells, which are widely applied to simulate the hepatic function of the human organism in vitro. This cell line was chose since recent studies have shown that the liver is potentially the most frequently targeted organ by cosmetic ingredients, and beyond that, considering the widely application of in vitro assays to test the cutaneous permeation of cosmetic products, including the assays applying modified Franz cells, this technique becomes indispensable. Three different cosmetic active substances were used, and the toxicity to HepG2 cells was assessed by the MTT method. The treatment with hyaluronic acid showed no toxicity to HepG2 cells. Treating the cells with P. guajava L. extract were verified that increasing the amount of the extract in the media, the cellular viability decreased, and finally, the treatment of alpha-lipoic acid showed a cytoprotective effect in relation to the treatment with propylene glycol. The study demonstrated the suitability in using HepG2 cells to assess the safety of cosmetic active substances, helping in the prediction of if the substance could be hepatotoxic if could reach the bloodstream
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)