995 resultados para Testes quimicos e reagentes


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Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz

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Realizaram-se testes físico-mecânicos e físico-químicos em couro de tilápia vermelha (Oreochromis spp.) a fim de testar a sua resistência. As amostras foram distribuídas em delineamento inteiramente ao acaso com dois tratamentos: no T1, procedeu-se à retirada do corpo-de-prova no sentido longitudinal e, no T2, à retirada do corpo-de-prova no sentido transversal. Para os testes de determinação da resistência à tração, alongamento e rasgamento progressivo, foi utilizado o dinamômetro EMIC, com velocidade de afastamento entre as cargas de 100 ± 20mm/min, em ambiente climatizado (± 23ºC e UR do ar de 50%), por 24 horas. A espessura do couro variou de 0,61 a 0,75mm, mas não houve diferença entre os sentidos analisados. O couro apresentou maior resistência à tração no sentido transversal, 25,89N/mm², (P<0,01), comparado ao sentido longitudinal, 14,20 N/mm². O alongamento foi significativamente (P<0,05) maior no sentido longitudinal, 80,8%, em relação ao transversal, 62,6%. Não houve diferença para o rasgamento progressivo entre os tratamentos. O couro apresentou teor de óxido de cromo de 3,8%, graxa de 15,1% e pH e cifra diferencial de 3,5 e 0,5, respectivamente. Os valores nos testes de resistência e físico-químicos apresentados pelo couro indicam que ele pode ser utilizado para a confecção de vestuário e artefatos de couro em geral.

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Background: Sulphites are widely used as a preservative and antioxidant additives in the food and pharmaceutical industries. Many types of biological and toxicological effects of sulphites in multiple organs of mammals have been shown in previous studies. Objective: The aim of this study was to investigate the effects of sodium metabisulfite (SMB) on testicular function and morphometric values of epididymis in adult male Wistar rats. Materials and Methods: A total of 32 rats were randomly divided into four groups. The experimental groups received SMB at doses of 10 mg/kg (S10), 100mg/kg (S100), and 260 mg/kg (S260) while an equal volume of normal saline was administered to the control group via gavage. The rats were anaesthetized after 28 days and the left testis with the head of epididimis was excised following abdominal incision for histological observation using hematoxylin and eosin staining. Serum samples were collected for assay of testosterone level. The initial epididymis was analyzed for motility, morphology, and the number of sperms. Result: The results of this study showed that normal morphology, count, and motility of sperms and testosterone level were decreased in the SMB treated groups. In comparison with the control group, SMB resulted in a lower total number of spermatogonia, primary spermatocyte, spermatids, and Leydig cells. Conclusion: It is suggested that SMB decreases the sperm production and has the potential to affect the fertility adversely in male rats.

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Testar software é uma das atividades que faz parte do desenvolvimento de software, e tem como objetivo apresentar evidências de confiabilidade contribuindo para uma maior qualidade do software. Esta atividade consome uma parte significativa do esforço de um projeto de desenvolvimento de software, sempre com o objetivo de encontrar erros antes da fase de manutenção, pois o custo de correção nesta fase pode ser até 100 vezes superior ao custo de correção na fase de conceção. Para auferir mais qualidade ao software, este pode ser certificado por uma norma de qualidade. As normas fornecem processos consistentes, rigorosos e uniformes para o desenvolvimento de software sempre com o objetivo de garantir qualidade ao software. As normas têm um papel importante na definição dos requisitos de teste, casos de teste e relatórios de teste que contemplam a atividade de testes permitindo elaborar um plano de testes mais rigoroso. Como o processo de testes é complexo no desenvolvimento de software, as ferramentas de automatização de testes de software permitem reduzir tempo, recursos e consequentemente os custos para a organização. A automatização deverá ser capaz de produzir os mesmos resultados obtidos através de um processo de testes manual, evidenciando sempre o resultado do teste. Deve também permitir a realização de testes sistemáticos e paralelos em diferentes ambientes de teste, sem o aumento do tempo e de recursos humanos. Nesta dissertação pretende-se desenvolver uma abordagem automatizada com o software Sikuli para a realização de testes seguindo a norma ISO/IEC 25051 para certificação de software. Depois da criação da abordagem e a respetiva criação de testes, é necessário validar a capacidade desta abordagem em comparação com uma abordagem de testes manuais.

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O teste de Friedman e a alternativa não paramétrica à ANOVA de medidas repetidas. Os testes de comparação múltipla são aplicados após a rejeição da hipótese nula do teste Friedman. Neste trabalho, realizamos um estudo de simulação para analisar a probabilidade de erro de Tipo I tanto no teste de Friedman como também nos testes de comparação múltipla mais usuais. Consideraram-se as distribuições discretas vulgarmente utilizadas para modelar dados de contagens, nas áreas da Biologia e da Ecologia. No teste de Friedman a taxa de erro de Tipo I empírica e menor quando se considera a estatística de teste com aproximação ao qui-quadrado. Nos testes de comparação múltipla, a probabilidade de erro de Tipo I aumenta com o aumento do número de blocos, e no teste LSD de Fisher também com o aumento do número de tratamentos. O teste dos Sinais e o mais conservativo e o teste LSD de Fisher o mais liberal.

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The authors present considerations about death and brain death concepts, as well the legal aspects for its diagnosis in Brazil. They also present the UNICAMP Protocol for the Diagnosis of Brain Death, revised and according with the current law, with standard techniques for the diagnostic exam. They emphasize the importance of a mature ethical position for this frequent and challenging situation.

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Attention deficit hyperactivity disorder (ADHD) is characterized by a persistent pattern of inattention and/or hyperactivity/impulsivity. The aim of this research was to contribute more precisely to the diagnosis of ADHD, to propose a battery of neuropsychological assessment and to analyze the contribution of each test. We studied 10 matched pairs of children with ADHD and normal controls (7 to 11 years). Inclusion criteria were: presence of ADHD typical behavior, positive diagnosis of ADHD based on DSM-IV, normal IQ, normal neurological examination and parental consent. We used extensive neuropsychological battery. The results showed differential sensitivity for detection of attentional problems in children with ADHD, although most tests did not reach statistical significance. The item, errors, of WCST revealed statistically significant difference between the two groups: ADHD performance was inferior to controls . In conclusion the neuropsychological assessment battery used in this research contributed to the diagnosis of ADHD.

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The aim of this work is to propose a methodology to evaluate the performance of students at Unicamp [São Paulo State University at Campinas] from admission to graduation. The sample consists of all students enrolled in Unicamp from 1997 to 2000, and the population corresponds to the universe of students throughout the existence of the university. The available database was gathered from socio-cultural questionnaires applied by the University Commission on College Entrance Examination at the time of enrollment for the examination (vestibular) and from academic information provided by the Unicamp Academic Studies Board. A methodology is proposed based on the relative gain variable suggested by Dachs and Maia (2006). This new methodology is based on the diversity measures proposed by Rao (1982) and on the use of U-statistics. Homogeneity tests have been proposed to assess whether there is a difference in performance among students from different groups.

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The present work aimed the development of a low cost servo-valve that answers to an electronic control signal, for variable rates liquid inputs application. A literature research to define which valve type should be used was made. A mechanically activated proportional valve with an electronically controlled servo-engine was designed and evaluated. Since developed the servo-valve, the system was submited to a number of tests .The evaluation of its behavior was obtained in terms of repeatability, hystheresis and linearity. The test was accomplished in a bench, specially developed for this aim. As a result, were obtained three curves of opening percentage as function of flow rate, describing three opening and closing increments in two different work pressures. The servo-valve presented a good repeatability, reasonable hysteresis and a typically quadratic curve. This one maintained the low cost target. These results were very satisfied because the non-linearity and the hysteresis could be easily corrected by software.

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In order to determine the energy needed to artificially dry an agricultural product the latent heat of vaporization of moisture in the product, H, must be known. Generally, the expressions for H reported in the literature are of the form H = h(T)f(M), where h(T) is the latent heat of vaporization of free water, and f(M) is a function of the equilibrium moisture content, M, which is a simplification. In this article, a more general expression for the latent heat of vaporization, namely H = g(M,T), is used to determine H for cowpea, always-green variety. For this purpose, a computer program was developed which automatically fits about 500 functions, with one or two independent variables, imbedded in its library to experimental data. The program uses nonlinear regression, and classifies the best functions according to the least reduced chi-squared. A set of executed statistical tests shows that the generalized expression for H used in this work produces better results of H for cowpea than other equations found in literature.

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Tomatoes are one of the most important vegetable crops grown in Brazil and are among the crops that have one of the highest post-harvest losses indexes in the country. The present work aimed at evaluating impact damage observed in packing lines of fresh tomatoes as well as to determine, under laboratory conditions, quality alterations of tomato fruits submitted to impact damage in different surface types. Critical points evaluation was accomplished using an instrumented sphere. Critical transference points found showed variations in acceleration levels from 30 to 129 G (m s-2). Tests carried out under laboratory conditions showed that padded surfaces reduced up to 31% impact damage. Incidence of severe internal physical damage was evaluated by a subjective scale and increased by 79% on hard surfaces for the highest fall drop. On the other hand, it was observed an effective reduction in physical damage on fruits when padded surfaces were used. When a 10-cm drop was performed, the maximum reduction measured was 10% for hard surfaces and 5% for previously padded surfaces. For quality parameters, it was observed for high drops on hard surfaces, highest values for weight loss, total acidity, lower values for vitamin C and Soluble Solids.

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Excessive and inadequate handling of fruits and vegetables provides high incidences of physical damage, consequently, post harvest losses. The main goal of this work was to evaluate the impact magnitude in persimmon packing lines, Rama Forte, and to determine, at the laboratory, its impact limits. For evaluating the critical points it was used an instrumented sphere of 76 mm of diameter (Technmark, Inc, Lansing, USA), which registered the impact magnitude in seven distinctive impact lines located in four packing houses. For determining physical damages, tests were carried out at the laboratory, where fruit drop was related to impact magnitude, physical damage incidence and fruit post harvest losses. At the packing lines, the values found varied from 21 to 87 G on the transfer points and the majority of registered impacts (over 94%) were down 50G. Drops from 20 cm caused an increase in weight losses after six days of storage at room temperature. Drops from 20 and 30 cm caused skin darkness (low L values), associated to a decrease in color intensity (chroma). Impact drop did not affect pulp fruit chemical features.

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The objectives were to identify factors associated with decreased life satisfaction in community-dwelling elderly and describe such factors according to gender and age bracket. The study interviewed 2,472 elderly individuals 65 years or older without cognitive deficits suggestive of dementia, in probabilistic samples from seven Brazilian cities. All measures were self-reported except for functional performance, indicated by handgrip and gait speed. Women had more chronic diseases, worse functional performance, and greater social involvement when compared to men. The oldest participants showed worse functional performance and less social involvement when compared to the youngest. Low satisfaction was associated with three or more diseases, memory problems, low social involvement, low handgrip strength, and urinary incontinence. The authors conclude that health, functional performance, and social involvement interact with well-being, so interventions targeting these areas can favor quality of life for the elderly.