952 resultados para Rendimento


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Learning difficulties can have a direct influence on the teaching-learning process of students by reducing their school performance. One factor that may contribute to this negative influence on learning refers to the presence of alternative conceptions, which may have different origins in the educational process. It is of paramount importance, for teachers, for example, to identify the concepts and the difficulties of their students in order for that knowledge can be able to contribute significantly to improve the teaching and learning process. From the following considerations, the present study (still in progress) aims to investigate aspects related to the concepts and difficulties of graduating students in relation to the contents of Biology. The participants of the research were undergraduate students in Biological Sciences from UFRN, studying by Distance Learning (Educação a Distância). To develop the survey, questionnaires were developed to identify the contents in Biology that these students have more difficulties as well as an interview to raise misconceptions regarding the content of cytology. Another tool developed was a textbook evaluation form, which was applied in conjunction with a questionnaire in workshops (short courses) in order to identify possible errors and mistakes that could jeopardize the process of teaching and learning, such as the importance that these learners assign to textbooks in the educational process. From the data collected, a booklet on the content of cytology was developed as a product. It is expected that it can be applied in classrooms in order to improve the teaching and learning in references to Biology, to minimize, for example, alternative conceptions than can occur related to the theme

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Para compreender as lesões desportivas (LD) é necessário quantificá-las, associando-as a fatores causais particulares ao esporte. Contudo, faltam registros sobre tais agravos nas instituições esportivas, sobretudo no atletismo brasileiro, em que poucos clubes possuem serviços de assistência à saúde. Na ausência de tais registros, estudos na área de saúde pública, utilizam-se de outros recursos epidemiológicos para coletas, tais como os inquéritos de morbidade referida. A partir dessa escassez de informações e a facilidade de obtenção de dados junto aos próprios atletas, objetivou-se, para esta pesquisa, levantar informações sobre LD referidas por atletas de alto rendimento, retrocedendo em oito meses, e compará-las com os registros de prontuários clínicos. Para tanto, foram tomados 25 atletas de elite, 16 do gênero masculino e nove do feminino, com idade de 25,7 ± 4,4 anos, altura de 1,74 ± 0,10m, peso 70,4 ± 13,15kg e tempo médio de treinamento de 8,38 ± 4,06 anos. Dois fisioterapeutas foram treinados separadamente para coletar informações sobre LD. Um deles em prontuários e o outro dos próprios atletas, através de entrevista (inquéritos de morbidade referida - IMR). Estudo de concordância de respostas para as duas formas de coleta foi realizado pelo teste da proporção binomial, estabelecendo-se limites de 95% de confiança para a concordância. Os resultados mostraram que em todas as variáveis estudadas os valores estavam dentro dos limites de confiança estabelecidos pelos testes estatísticos, sendo: 88,33% para as variáveis tipo de lesão ou agravo e mecanismo de lesão ou aumento dos sintomas, 90% para a variável qualidade do retorno às atividades desportivas e 91,67% para as variáveis local anatômico e período de treinamento. Concluiu-se que houve elevada taxa de concordância entre as informações levantadas, mostrando a eficácia do IMR para a coleta de informações sobre lesões desportivas para a população investigada.

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Várias amostras de solo do Brasil foram semeadas em placas de ágar e diversas cepas de actinomicetos produtoras de antibióticos antifúngicos foram isoladas. Foram desenvolvidos meios para eliciação da biossíntese dos antibióticos e métodos para determinação rápida do seu rendimento. Ao todo, foram isoladas 41 cepas de actinomicetos aeróbios produtoras de metabólitos antifúngicos. Destes, 11 (26,8%) eram macrolídeos tetraênicos, 13 (31,7%) macrolídeos pentaênicos, 1 (2,4%), macrolídeo oxopentaênico, 1 (2,4%) macrolídeo hexaênico e 6 (14,6%) macrolídeos heptaênicos. Os antibióticos antifúngicos produzidos pelas restantes 9 cepas ativas (21,9%) não eram poliênicos. Os poliênicos mais utilizados atualmente na clínica são do tipo tetraênico (nistatina) e heptaênico (anfotericina B). Um meio à base de leite de soja favoreceu extraordinariamente a eliciação da biossíntese de polienos por algumas cepas, enquanto que para outras não houve favorecimento e para outras foi prejudicial. Os rendimentos obtidos atingiram cerca de 6000 U de antibióticos poliênicos por mL.

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As características físico-químicas do maracujá amarelo em três estádios de cor de casca (1/3 amarelo, 2/3 amarelo e inteiro amarelo), em quatro épocas da safra/99 foram avaliadas, visando estabelecer o ponto de colheita de melhor qualidade da fruta para a industrialização. Foram determinados o tamanho dos frutos, a cor da casca e da polpa, o rendimento de extração da polpa, o teor de sólidos solúveis totais, o pH, a acidez total, o ratio e o teor de vitamina C. Foi empregado o delineamento experimental inteiramente casualizado, com 8 repetições, 5 frutos por parcela e 3 tratamentos. Os resultados mostraram que o rendimento de polpa não apresentou diferença significativa entre os tratamentos e entre as colheitas. Com relação à cor da polpa, houve diferença significativa entre os três estádios apenas na 1ª colheita. Os frutos de casca 1/3 amarela apresentaram teor de sólidos solúveis significativamente inferior aos demais apenas na 3ª e 4ª colheitas, mas o maior valor médio ocorreu na 4ª colheita. O teor de acidez total dos frutos de casca inteira amarela foi significativamente inferior àqueles das colheitas 2, 3 e 4. Os valores mais elevados de vitamina C foram obtidos na 1ª colheita e, os frutos de casca 1/3 amarela apresentaram teores significativamente inferiores nas colheitas 1 e 2. de maneira geral, os resultados indicaram que, embora tenham ocorrido algumas diferenças nas características físico-químicas dos frutos nos diferentes estádios de cor de casca, frutos colhidos em todos os estádios de cor de casca estudados apresentaram-se adequados à industrialização.

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Backgroud: Obesity is a major public health problem and is related to the low physical capacity when obese are compared to no-obese people, however the cause of this limitation is not completely understood. The measurement associated of physiological response to the telemetric 6MWT adds information of metabolic and respiratory system for diagnose of the functional limitation. Objective: Analyze physiological, metabolic and ventilatory responses in women with different body fat during the 6MWT. Methods: 32 women (8 non-obese, 8 Overweight, 8 Obese and 8 morbidly obese) were evaluated for anthropometry, lung function and exercise capacity. Results: Morbidly obese walked the shortest distance (400.2±38.7m), had lower VO2/Kg (12.75±3.20l/Kg/min) and lower R (0.74± 0.11) in the 6MWT compared to other groups. Analyses of metabolic (VO2 and VCO2) and respiratory (VE, VT and BF) during the test did not identify differences between groups. The evaluation of cardiac function (O2 pulse) found higher values in the OM (12.3 ± 4.9ml/bat). Conclusion: The OM had worse performance in the 6MWT compared to other groups. The physical performance may be reduced in this population related to a protocol-dependent response because the speed of 6MWT is self-adjusted allows the individual himself select the intensity of the test, making it set at a speed where there is energy saving

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As más condições laborais e a forma de organização do trabalho dentro do sistema capitalista frequentemente têm se mostrado nocivas para o trabalhador. Além disso, a chamada síndrome da fadiga crônica é um dos males que acomete a classe trabalhadora. Por meio de revisão teórica buscou-se caracterizar a síndrome, suas possíveis causas e consequências e o papel do psicólogo nas organizações. A fadiga pode ser compreendida como um esgotamento físico e mental, culminando em consequências para a saúde do trabalhador. Excesso de trabalho, pressão por produção, turnos alternados, riscos físicos e falta de autonomia são alguns fatores apontados como prováveis desencadeadores da síndrome, e as consequências encontradas vão desde baixo rendimento e maior risco de acidentes de trabalho até dificuldade para relaxar em momentos de lazer. É papel do psicólogo do trabalho e organizacional realizar ações remediadoras e preventivas que impeçam ou dificultem o aparecimento da fadiga no trabalho.

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The objective of this study was to evaluate the quality of housing and the physical and chemical characteristics of meat from sheep raised on pasture Brachiaria brizantha and Panicum maximum. The experiment was conducted in the physical area of the Study Group on Forage (GEFOR), located in the Academic Unit Specialized in Agricultural Sciences - Federal University of Rio Grande do Norte - UFRN in Macaíba, RN, Brazil. We used 32 lambs SPRD, obtained from herds in the state, with liveweight (LW) of 24.5 kg were assigned randomly to four treatments consisting of tropical grasses, two cultivars of Brachiaria brizantha, Marandu and Piatã, and two of Panicum maximum, Aruana and Massai. The experimental area was 2.88 ha, divided into 4 paddocks of 0.72 ha, where each picket consisted of a farm and was divided into six plots of 0.12 ha, where the animals remained under rotational grazing. The period of adaptation to the pickets was seven days. At the beginning of the experiment the animals were weighed, identified with plastic earrings and necklaces colored according to the treatment, and treated against. The lambs were loose in the paddock at 8 am and collected at 16 hours, which returned to collective pens. During the time of grazing animals had free access to mineral supplement with monensin Ovinofós ® and water. Before entering the paddocks of pasture were sampled to characterize the chemical composition. Every seven days occurred at weighing, with fasting, to monitor the weight development. Cultivars Marandu, Aruana, Piatã and Massai were grazed for 133, 129, 143 and 142 days, respectively, until the lambs reach slaughter weight. Arriving at 32 kg lambs were evaluated subjectively for body condition score by, passed through fasting period, diet and water for 16 hours were slaughtered. Measurements were made in the inner and outer casings in addition to subjective evaluations regarding muscling, finish and quantity of pelvic-renal fat, then each was divided longitudinally into two half-carcases and cuts were made in the commercial left half, and after heavy calculated their income. Between the 12th and 13th thoracic vertebrae, was performed a cut to expose the cross section of the Longissimus dorsi, which was drawn on the rib eye area (REA) in transparent film. Fat thickness and extent of AOL GR were determined using a caliper. A tissue composition was determined by dissection of the legs. Analyzes were performed physical (color, cooking loss and shear force) and chemical composition of meat (moisture, ash, protein and lipids) in Longissimus dorsi muscle. Grazing tropical grass Brachiaria brizantha cvs. Marandu and Piatã and Panicum maximum cvs. Aruana and Massai can be used for lambs SRPD in the rainy season, because not alter the physico-chemical and chemical composition of meat

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The direct relationship with the processing, industrial yield and price of milk, the importance of the centesimal composition of milk and their protein fractions has increased for both the dairy industry and for the producers, so it is important to identify the possible causes on variation of these components. The aim of this study was to evaluate the effect of the seasons, order of calving and lactation phase on milk composition and protein fractions in dairy farms in the Agreste and Leste meso-regions, of Rio Grande do Norte State (RN). Milk samples were taken in seven milk farms directly from the bulk tanks except for one farm where samples were taken from higher milking cows producers and heifers. The experiment was done in seven properties with milk samples taken directly from the bulk tanks and in one property were collected from higher production cows and heifers. Composition analyses were carried out for both experiments and sensorial trial was performed for the second experiment only. The data results were submitted to analysis of variance (ANOVA) and Tukey test performed for 5% significance level. In the first experiment was observed response of the seasons, dry and rainy season; while in the second, the effect of the order of calving and lactation phase had influence on milk composition and protein fractions. There was significant response (p < 0.05) for season effects but due to farms. The rainy season had higher averages in the protein, lactose, total solids and nonfat dry extract. Multiparous cows had higher CCS, NUL and PCAS milk contents; while, first calving heifers showed higher average for the sensory attribute, color of milk. The final third of lactation was responsible for the elevation of the levels of almost all milk components and their protein fractions

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O aumento significativo da produção de milho na segunda safra no Brasil, principalmente no centro-sul do país, têm estimulado os programas de melhoramento da cultura a selecionar genótipos que sejam adaptáveis às condições climáticas das diferentes épocas de semeadura. Nesse sentido, o objetivo do presente trabalho foi quantificar a interação progênies x épocas de semeadura e verificar seus reflexos no progresso genético com o uso de índice de seleção multivariado para seleção de progênies do Composto Isanão VF-1 de milho. As semeaduras foram realizadas na segunda safra em 2004 e na primeira safra do ano agrícola 2004/05. Foram utilizadas 71 progênies de meios irmãos avaliadas em blocos ao acaso, com três repetições. Os caracteres avaliados foram: altura de plantas, altura de espigas, tombamento, prolificidade e rendimento de grãos. Realizaram-se a decomposição da interação progênies x épocas e foram estimados os ganhos pelo índice de seleção descrito por Mulamba e Mock. Houve predomínio da interação do tipo simples para maioria dos caracteres, exceto para prolificidade, que revelou 86% de interação do tipo complexa. Pelo índice de Mulamba e Mock, os ganhos proporcionais mais adequados para o conjunto de caracteres avaliados foi obtido pelos pesos econômicos atribuídos por tentativas. Os ganhos preditos foram de 1,41, 0,86, -13,03, 9,54 e 16,12% para altura de planta, altura de espiga, tombamento, prolificidade e rendimento de grãos, respectivamente.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This study proposes to find a biodiesel through transesterification of rice bran oil with KI/Al2O3 checking the influence of two types of alumina (Amorphous and Crystalline) for conversion into methyl esters. The catalyst was synthesized by the wet impregnation method. Adding 30 mL of 35% KI(aq.) in 10 g of alumina, under stirring at 80 °C for 3 hours. The reaction conditions used in this study were optimized, with a molar ratio methanol:oil of 15:1, 8 h of reaction time and reflux temperature. The catalyst amount was varied in the range of 1 to 5 % wt. The solid catalysts materials were analyzed by: x-ray diffraction (XRD), thermogravimetry (TG), N2 adsorption/desorption, scanning electron microscopy (SEM) and basicity, for the identification of its structure and composition, verifying the presence of basic sites. The results showed that Al2O3(A) presents an amorphous structure, high surface area and a better catalytic activity, in relation to the catalyst synthesized with Al2O3(C) support that proved to have a more crystalline structure, having as well, a lesser surface area, enabling difficulties for the incorporation of active sites. The obtained biodiesel with 5% wt. KI/Al2O3(A) presented physicochemical properties within the standards specified by the Resolution No 7/2008 ANP and obtained the best reaction yield with 95.2%, according to quantitative measurement from the TG, which showed 96.2% conversion into methyl esters. It was furthermore found that with the increasing amount of the quantity of the catalyst in the reaction, there was also an increase in the ester content obtained. The specific mass and the kinematic viscosity were reduced with the increase of the amount of quantity of the catalyst, indicating an increase in the conversion of triglycerides

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The cultivation of microalgae biomass in order to produce biodiesel arises as an extremely promising aspect, in that the microalgae culture includes short cycle of reproduction, smaller areas for planting and residual biomass rich in protein content. The present dissertation evaluates the performance and features, through spectrometry in the region of infrared with transformed Fourier (FTIR) and spectrometry in the region of UVvisible (UV-Vis), of the extracted lipid material (LM) using different techniques of cell wall disruption (mechanical agitation at low and at high spin and agitation associated with cavitation). The technique of gas chromatography (GC) brought to light the success of alkaline transesterification in the conversion of oil into methyl monoesters (MME), which was also analyzed by spectroscopic techniques (FTIR, proton magnetic resonance (1H NMR) and carbon (13C NMR). Through thermogravimetric analysis (TGA) were analyzed the lipid material (LM), biodiesel and the microalgae biomass. The method which provided the best results concerning the efficiency in extraction of the LP of Monoraphidium sp. (12,51%) was by mechanical agitation at high spin (14 000 rpm), for 2 hours being the ideal time, as shown by the t test. The spectroscopic techniques (1H NMR, 13C NMR and FTIR) confirmed that the structure of methyl monoesters and the chromatographic data (CG) revealed a high content of saturated fatty acid esters (about 70%) being the major constituent eicosanoic acid (33,7%), which justifies the high thermal stability of microalgae biodiesel. The TGA also ratified the conversion rate (96%) of LM into MME, pointing out the quantitative results compatible with the values obtained through GC (about 98%) and confirmed the efficiency of the extraction methods used, showing that may be a good technique to confirm the extraction of these materials. The content of LM microalgae obtained (12,51%) indicates good potential for using such material as a raw material for biodiesel production, when compared to oil content which can be obtained from traditional oil for this use, since the productivity of microalgae per hectare is much larger and requires an extremely reduced period to renew its cultivation

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Drying of fruit pulps in spouted beds of inert particles has been indicated as a viable technique to produce fruit powders. Most of the processes employed to produce dried fruit pulps and juices, such as Foam Mat, encapsulation by co-crystallization and spray drying utilize adjuvant and additives (such as thickeners, coating materials, emulsifiers, acidulants, flavors and dyes), which is not always desirable. The fruit pulp composition exerts an important effect on the fruit powder production using a spouted bed. In the study by Medeiros (2001) it was concluded that lipids, starch and pectin contents play an important role on the process performance, enhancing the powder production; however, the drying of fruit pulps containing high content of reducing sugars (glucose and fructose) is practically unviable. This work has the objective of expanding the studies on drying of fruit pulps in spouted bed with aid of adjuvant (lipids, starch and pectin) aiming to enhance the dryer performance without jeopardizing the sensorial quality of the product. The optimum composition obtained by Medeiros (2001) was the basis for preparing the mixtures of pulps. The mixture formulations included pulps of mango (Mangifera indica), umbu (Spondias tuberosa) and red mombin (Spondia purpurea) with addition of cornstarch, pectin and lipids. Different products were used as lipids source: olive and Brazil nut oils, coconut milk, heavy milk, powder of palm fat and palm olein. First of all, experiments were conducted to define the best formulation of the fruit pulps mixture. This definition was based on the drying performance obtained for each mixture and on the sensorial characteristics of the dry powder. The mixture formulations were submitted to drying at fixed operating conditions of drying and atomizing air flow rate, load of inert particles, temperature and flow rate of the mixture. The best results were obtained with the compositions having powder of palm fat and palm olein in terms of the drying performance and sensorial analysis. Physical and physicochemical characteristics were determined for the dry powders obtained from the mixtures formulations. Solubility and reconstitution time as well as the properties of the product after reconstitution were also evaluated. According to these analyses, the powder from the mixtures formulations presented similar characteristics and compatible quality to those produced in other types of dryers. Considering that the palm olein is produced in Brazil and that it has been used in the food industry substituting the palm fat powder, further studies on drying performance were conducted with the composition that included the palm olein. A complete factorial design of experiments 23, with three repetitions at the central point was conducted to evaluate the effects of the air temperature, feeding flow rate and intermittence time on the responses related to the process performance (powder collection efficiency, material retained in the bed and angle of repose of the inert particles after the process) and to the product quality (mean moisture content, loss of vitamin C and solubility). Powder production was uniform for the majority of the experiments and the higher efficiency with lower retention in the bed (59.2% and 1.8g, respectively) were obtained for the air temperature of 80°C, mixture feed rate of 5ml/min in intervals of 10 min. The statistical analysis of the results showed that the process variables had individual or combined significant influences on the powder collection efficiency, material retention in the bed, powder moisture content and loss of vitamin C. At the experimental ranges of this work, the angle of repose and solubility were not influenced by the operating variables. From the results of the experimental design, statistical models were obtained for the powder moisture content and loss of vitamin C

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Most of the energy consumed worldwide comes from oil, coal and natural gas. These sources are limited and estimated to be exhausted in the future, therefore, the search for alternative sources of energy is paramount. Currently, there is considerable interest in making trade sustainable biodiesel, a fuel alternative to fossil fuels, due to its renewable nature and environmental benefits of its use in large scale. This trend has led the Brazilian government to establish a program (Probiodiesel) with the aim of introducing biodiesel into the national energy matrix, by addition of 5% biodiesel to conventional diesel in 2010 to foster not only the increase of renewable energy, but reduce imports of crude oil. This work evaluates different methods of extraction of oil Carthamus tinctorius L., their characterization by IR, 1H and 13C NMR, HPLC and TG and their use in the production of methyl ester (molar ratio of oil / alcohol 1:6, and NaOH catalyst). The physico-chemical parameters (acid value, density, viscosity, saponification index and surface tension) of oil and biodiesel were also described. The produced biodiesel had a yield of 93.65%, was characterized in relation to their physicochemical properties showing satisfactory results (density=875 kg/m3, viscosity = 6.22 mm2/s, AI = 0.01 mg (NaOH) /g) compared with the values established by the the National Agency Oil, Natural Gas and Biofuels

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As influências do sistema de preparo do solo e da adubação nitrogenada não estão bem definidas para o arroz de terras altas. Assim, com o objetivo de avaliar os componentes da produtividade e o rendimento industrial do arroz de terras altas irrigado por aspersão, em função do preparo do solo e de doses de nitrogênio em cobertura, conduziu-se o experimento em condições de campo, em Selvíria (MS), por duas safras consecutivas: 2003/2004 (cultivar BRS Talento) e 2004/2005 (cultivar IAC 202). Adotou-se o delineamento em blocos casualizados, constituído pela combinação de três manejos de solo (grade aradora + grade niveladora, escarificador + grade niveladora e plantio direto) e seis doses de N em cobertura (0 kg ha-1, 25 kg ha-1, 50 kg ha-1, 75 kg ha-1, 100 kg ha-1 e 125 kg ha-1), com quatro repetições. Avaliou-se a concentração de N na folha, altura de plantas, componentes de produção, produtividade e o rendimento industrial dos grãos. O preparo do solo com escarificador + grade niveladora propiciou a obtenção de maiores produtividades das duas cultivares, enquanto a adubação nitrogenada em cobertura interferiu apenas na produtividade da cultivar IAC 202, sem afetar o rendimento industrial de grãos.