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Search Results: 1 - 10 of 695513 matches for " Estêv?o M. R. Araújo "
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Development of a New Bio-Based Insulating Fluid from Jatropha curcas Oil for Power Transformers  [PDF]
José M. G. Evangelista Jr., Fabrício E. Bortot Coelho, Juliana A. O. Carvalho, Estêvo M. R. Araújo, Tania L. S. Miranda, Adriane Salum
Advances in Chemical Engineering and Science (ACES) , 2017, DOI: 10.4236/aces.2017.72018
Abstract: The present work aims to develop a new vegetable insulating fluid for power transformers based on Jatropha curcas oil. Besides its technical benefits, Jatropha curcas oil has a socio-economic role by promoting income to rural families, contributing to the countryside development and avoiding rural exodus. Thus, the entire transformer oil production (extraction, processing, characterization and accelerated aging) was covered and a new process was developed. For oil extraction, the most suitable process was the solvent extraction (5 mL of hexane per gram of crushed non-peeled seeds during 30 minutes) with an oil yield of 32%. In raw oil processing stage, the degumming, with 0.4 g of phosphoric acid per 100 g of oil, at 70°C, was used to remove phosphatides. Then, free fatty acids were 96% neutralized with a sodium hydroxide solution (0.5% w/w) at room temperature. For the oil clarification, the combination of 5% w/woil of activated carbon and 1% w/woil of MgO resulted in a bright, odorless and clear oil with an acid number of 0.04 mgKOH·g1. The oil drying in a vacuum rotary evaporator, at 70°C, for 2 hours reduced the water content to 177 ppm. The processed oil was characterized following ASTM D6871 methods. This oil presented higher dielectric breakdown voltage (55 kV) than commercial transformer fluids (BIOTEMP?, EnvirotempFR3?, and Bivolt?), which increases transformer safety, capacity and lifetime. In addition, the processed oil has a lower viscosity than BIOTEMP? fluid, which can enhance the heat dissipation efficiency in the transformer. Moreover, the processed oil flash and fire points of 310°C and >340°C, respectively, confirm the great security of vegetable insulating fluids. The analyzed properties of the processed oil fulfill all the ASTM D6871, ABNT NBR 15422 and IEC 62770 specifications. Therefore, Jatropha curcas oil is a potential substitute formineral insulating fluids.
Avalia??o in vitro do fungo predador de nematoides Duddingtonia flagrans sobre larvas infectantes de ciatostomíneos de equinos (Nematoda: Cyathostominae)
Fabio R., Braga;Araújo, Jackson V.;Araujo, Juliana M.;Silva, André R.;Carvalho, Rogério O.;Campos, Artur K.;
Revista Brasileira de Parasitologia Veterinária , 2009, DOI: 10.4322/rbpv.018e1018
Abstract: the predatory capacity of one isolate of nematode-trapping fungus duddingtonia flagrans (ac001) on infective larvae of cyathostomes was evaluated in laboratorial conditions in medium water-agar 2% (wa 2%). there was significant reduction (p < 0. 01) of 93.64% in the average of infective larvae of cyathostomes recovered of medium wa 2% at seven day. these results show that the isolated ac001 could be used in the biological control of cyathostomes of horses.
Metástase de adenocarcinoma mamário para a hipófise: relato de caso
Zambelli, Heller J. L;Brito, José Nazareno P.O.;Assump??o, Ligia V. M.;Araújo, Alessandra A. Q.;Zambelli, Eliane R. L.;Parmigiani, Alessandro M.;
Arquivos de Neuro-Psiquiatria , 1996, DOI: 10.1590/S0004-282X1996000100021
Abstract: a case of breast adenocarcinoma metastatic to the pituitary gland in a 57-year-old brazilian female is presented. the computerized imaging may cause differential diagnostic confusion between a benign primary pituitary process and metastatic disease. resolution of doubts by surgery is important for determining appropriate treatment.
Efeitos do treinamento físico contra resistência sobre a composi??o corporal e a potência muscular em adultos deficientes de horm?nio do crescimento
Brasil, Rosane R.L.O.;Concei??o, Flávia L.;Coelho, Carla W.;Rebello, Cláudio V.;Araújo, Claudio G.S.;Vaisman, Mário;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2001, DOI: 10.1590/S0004-27302001000200004
Abstract: growth hormone (gh) deficiency syndrome in adults is well established, as well as the benefits of replacement with recombinant gh. body composition changes are frequently studied in these patients, and are characterized by an increase in total body fat with predominant trunk obesity, a decrease in lean body mass, muscular strength and total body water. all of these features are almost completely reversed after recombinant gh therapy. this study evaluated body composition and muscle power in 11 gh-deficient patients before and after undergoing a resistance-training program for 12 weeks without gh replacement. we evaluated the body composition by measuring girths, skinfolds, weight, height, body mass index, waist-hip ratio and abdominal computerized tomography. muscle power was assessed in several muscle groups by mean of five exercises in a muscle-training machine, to which a tensiometer was attached. the data analysis showed that there were no changes in body composition, body mass index, waist-hip ratio and weight. when we studied separately the sum of central and peripheral skinfolds, we noted a volume reduction in the sum of central skinfolds. with relation to muscular strength and power there was no gain in handgrip muscular strength (p>0.05), whereas muscular power showed a significant increase after the training (p<0.01). we concluded that when these patients are submitted to a home-based training program of resistance - type exercises they gain muscular power, and that this type of exercise is a therapeutic alternative that can improve their quality of life whenever the use of recombinant gh is not possible.
Gran method for end point anticipation in monosegmented flow titration
Aquino, Emerson V;Pasquini, Celio;Rohwedder, Jarbas J. R;Raimundo Jr, Ivo M;Montenegro, M. Concei??o B. S. M;Araújo, Alberto N;
Journal of the Brazilian Chemical Society , 2004, DOI: 10.1590/S0103-50532004000100017
Abstract: an automatic potentiometric monosegmented flow titration procedure based on gran linearisation approach has been developed. the controlling program can estimate the end point of the titration after the addition of three or four aliquots of titrant. alternatively, the end point can be determined by the second derivative procedure. in this case, additional volumes of titrant are added until the vicinity of the end point and three points before and after the stoichiometric point are used for end point calculation. the performance of the system was assessed by the determination of chloride in isotonic beverages and parenteral solutions. the system employs a tubular ag2s/agcl indicator electrode. a typical titration, performed according to the iupac definition, requires only 60 ml of sample and about the same volume of titrant (agno3) solution. a complete titration can be carried out in 1 - 5 min. the accuracy and precision (relative standard deviation of ten replicates) are 2% and 1% for the gran and 1% and 0.5% for the gran/derivative end point determination procedures, respectively. the proposed system reduces the time to perform a titration, ensuring low sample and reagent consumption, and full automatic sampling and titrant addition in a calibration-free titration protocol.
Solvent Extraction of Citric Acid with Different Organic Phases  [PDF]
Estêvo Magno Rodrigues Araújo, Fabrício Eduardo Bortot Coelho, Julio Cézar Balarini, Tania Lúcia Santos Miranda, Adriane Salum
Advances in Chemical Engineering and Science (ACES) , 2017, DOI: 10.4236/aces.2017.73023
Abstract: The present work aimed at the study of citric acid solvent extraction in order to establish the composition of the organic phase and to obtain thermodynamic and kinetic data for the chosen system. Discontinuous extraction experiments in a single stage were performed from a synthetic solution of citric acid, with the typical concentration (10% w/v) observed in industrial fermented musts. Exploratory experiments were carried out using different organic phases in order to select the most suitable solvent phase to further continuous extraction tests in a mechanically agitated column. The selected organic phase composition was: Alamine 336, ExxalTM 13 tridecyl alcohol, and the aliphatic diluent EscaidTM 110. Next, the effects of the contact time and of the concentrations of extractant and modifier on the citric acid extraction were studied. Among the investigated conditions, the best one was 10 minutes of contact time, 30% w/v of Alamine 336, and 10% w/v of ExxalTM 13 tridecyl alcohol. For this condition, the equilibrium isotherm (28°C ± 2°C) was determined, and the equilibrium constant was calculated (36.8 (mol·L-1)-1.5). It was considered that trioctylamine and citric acid complexation reaction occurs mainly with non-dissociated citric acid form, because the aqueous feed solutions’ pH is lower than the citric acid pKa1. It was found that 1.5 molecules of the extractant, on average, are required to react with one citric acid molecule, which can indicate that reactions with different extractant/citric acid ratios occur simultaneously. Next, the rate constants for the direct and inverse reactions, 2.10 (mol·L-1)-1.5·s-1 and 5.69 × 10-2 s-1, respectively, were calculated. Coefficients of determination (R2) values higher than 0.93 were found in these calculations, suggesting that the results obtained using a computer modeling would be very close to those results obtained experimentally. Therefore, the present work provides data required to future modelling, design, and simulation of citric acid solvent extraction processes.
Rendimento de mel o amarelo cultivado em diferentes tipos de cobertura do solo e métodos de plantio
Araújo Ant?nio de P.,Negreiros Maria Z. de,Leit?o Mário de M. V. B. R.,Pedrosa Josué F.
Horticultura Brasileira , 2003,
Abstract: Avaliou-se o rendimento de mel o amarelo em diferentes tipos de cobertura do solo e métodos de plantio, em experimento na Fazenda água Branca (FRUNORTE), no município de Carnaubais-RN. O delineamento experimental foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repeti es. As parcelas foram constituídas pelas coberturas do solo [palha de carnaúba, filme de polietileno preto, filme de polietileno dupla face (prateado e preto) e solo descoberto] e as subparcelas pelos métodos de plantio (semeadura direta e transplante direto com produ o de mudas em tubetes de 125 mL, copos plásticos de 180 mL e bandejas de 72 células). As características avaliadas foram peso médio de frutos comerciáveis, número de frutos comerciáveis, produtividade de frutos comerciáveis e n o comerciáveis e classifica o dos frutos. As coberturas do solo e os métodos de plantio n o apresentaram efeito significativo para número, peso médio e produtividade de frutos comerciáveis e n o comerciáveis. Em rela o ao mercado externo, as coberturas do solo proporcionaram maior concentra o de frutos tipos 5 e 6, enquanto que para o mercado interno, registrou-se maior percentagem de frutos dos tipos 5 a 8.
Cerebellar hemorrhage as a complication of temporal lobectomy for refractory medial temporal epilepsy: report of three cases
Paola, Luciano de;Troiano, André R.;Germiniani, Francisco M.B.;Coral, Patrícia;Della Coletta, Marcus V.;Silvado, Carlos E.S.;Moro, Marlus;Araújo, Joo Candido de;M?der, Maria Joana;Werneck, Lineu C.;
Arquivos de Neuro-Psiquiatria , 2004, DOI: 10.1590/S0004-282X2004000300026
Abstract: cerebellar hemorrhage is listed among the potential complications following neurosurgical pro ce dures. in this scenario it is usually reported as a rare condition. however, it seems that epilepsy surgery pa tients are somewhat more prone to this kind of complication, compared to other surgical groups. head po si tioning, excessive cerebral spinal fluid draining and the excision of non-expanding encephalic tissue (or combinations among the three) are likely to be cause underlying remote cerebellar hemorrhage. out of the 118 atl/ah performed at our institution, between 1996 and 2002, we identified 3 (2.5%) patients pre sen ting with cerebellar hemorrhage. we report on such cases and review the literature on the topic.
Genetic and antigenic analysis of Babesia bigemina isolates from five geographical regions of Brazil
Madruga, Claudio R.;Leal, Cássia R.B.;Ferreira, Alda M.T.;Araújo, Flábio R.;Bonato, Ana L.V.;Kessler, Raul H.;Schenk, Maria A.M.;Soares, Cleber O.;
Pesquisa Veterinária Brasileira , 2002, DOI: 10.1590/S0100-736X2002000400005
Abstract: a molecular epidemiological study was performed with babesia bigemina isolates from five geographical regions of brazil. the genetic analysis was done with random amplification of polymorphic dna (rapd), repetitive extragenic palindromic elements-polymerase chain reaction (rep-pcr) and enterobacterial repetitive intergenic consensus sequences-polymerase chain reaction (eric-pcr) that showed genetic polymorphism between these isolates and generated fingerprinting. in rapd, ilo872 and ilo876 primers were able to detect at least one fingerprinting for each b. bigemina isolate. the amplification of b. bigemina dna fragments by rep-pcr and eric-pcr gave evidence for the presence in this haemoprotozoan of the sequences described previously in microorganisms of the bacterial kingdom. for the first time it was demonstrated that both techniques can be used for genetic analysis of a protozoan parasite, although the eric-pcr was more discriminatory than rep-pcr. the dendogram with similarity coefficient among isolates showed two clusters and one subcluster. the northeastern and mid-western isolates showed the greatest genetic diversity, while the southeastern and southern isolates were the closest. the antigenic analysis was done through indirect fluorescent antibody technique and western blotting using a panel of monoclonal antibodies directed against epitopes on the merozoite membrane surface, rhoptries and membrane of infected erythrocytes. as expected, the merozoite variable surface antigens, major surface antigen (msa)-1 and msa-2 showed antigenic diversity. however, b cell epitopes on rhoptries and infected erythrocytes were conserved among all isolates studied. in this study it was possible to identify variable and conserved antigens, which had already been described as potential immunogens. considering that an attenuated babesia clone used as immunogen selected populations capable of evading the immunity induced by this vaccine, it is necessary to evaluate more deeply
The controvertible role of kava (Piper methysticum G. Foster) an anxiolytic herb, on toxic hepatitis
Amorim, Maria F. D.;Diniz, Margareth F. F. M.;Araújo, Maria S. T.;Pita, Joo C. L. R.;Dantas, Jadson G.;Ramalho, Josué A.;Xavier, Aline L.;Palomaro, Thayse V.;B. Júnior, Nelson L.;
Revista Brasileira de Farmacognosia , 2007, DOI: 10.1590/S0102-695X2007000300020
Abstract: kava is an anxiolytic herbal medicine used in the treatment of sleep and anxiety disorders. some cases of kava-induced hepatotoxicity have been reported in the literature leading to its banishment in most countries worldwide. clinically, the spectrum ranged from transient elevations of liver enzyme levels to fulminant liver failure and death. liver transplantation was performed in a few cases. this paper provides a review of the currently available literature on kava-related toxic hepatitis which may result from its use, discusses the possible mechanisms for the potentially severe hepatotoxicity and describes some features which must be considered when adverse liver effects seem to be associated to kava administration. in conclusion, the incidence of kava toxicity on the liver remains to be investigated; however, some concerns before or during kava use are important, due to the possibility of severe liver dysfunction.
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