967 resultados para Redutores de velocidade
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The present study provides a methodology that gives a predictive character the computer simulations based on detailed models of the geometry of a porous medium. We using the software FLUENT to investigate the flow of a viscous Newtonian fluid through a random fractal medium which simplifies a two-dimensional disordered porous medium representing a petroleum reservoir. This fractal model is formed by obstacles of various sizes, whose size distribution function follows a power law where exponent is defined as the fractal dimension of fractionation Dff of the model characterizing the process of fragmentation these obstacles. They are randomly disposed in a rectangular channel. The modeling process incorporates modern concepts, scaling laws, to analyze the influence of heterogeneity found in the fields of the porosity and of the permeability in such a way as to characterize the medium in terms of their fractal properties. This procedure allows numerically analyze the measurements of permeability k and the drag coefficient Cd proposed relationships, like power law, for these properties on various modeling schemes. The purpose of this research is to study the variability provided by these heterogeneities where the velocity field and other details of viscous fluid dynamics are obtained by solving numerically the continuity and Navier-Stokes equations at pore level and observe how the fractal dimension of fractionation of the model can affect their hydrodynamic properties. This study were considered two classes of models, models with constant porosity, MPC, and models with varying porosity, MPV. The results have allowed us to find numerical relationship between the permeability, drag coefficient and the fractal dimension of fractionation of the medium. Based on these numerical results we have proposed scaling relations and algebraic expressions involving the relevant parameters of the phenomenon. In this study analytical equations were determined for Dff depending on the geometrical parameters of the models. We also found a relation between the permeability and the drag coefficient which is inversely proportional to one another. As for the difference in behavior it is most striking in the classes of models MPV. That is, the fact that the porosity vary in these models is an additional factor that plays a significant role in flow analysis. Finally, the results proved satisfactory and consistent, which demonstrates the effectiveness of the referred methodology for all applications analyzed in this study.
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The brazilian-plum (Spondias tuberosa, His) is a tropical fruit tree that has been consolidated in the market for agribusiness processing, due to its characteristic flavor of fruit. Accordingly, studies to optimize the propagation of plants are necessary for production of seedlings with agronomic and quality assurance measures. This study aimed at determining the efficient techniques for uniform seed germination, as brazilian-plum seed present mechanical dormancy, and establish optimal culture media for multiplication of shoots from the in vitro micropropagation. Firstly, in a greenhouse at the Universidade Federal do Rio Grande do Norte, was evaluated the influence of different methods of breaking dormancy in the emergence of seedlings of brazilian-plum and speed of germination (IVG) of seeds. After 60 days of cultivation, it was found that splay in the distal portion of the seed was the best treatment, with rates of 85.33% in germinability and 3.415 of IVG, compared with the treatment of seed-soaking in water for 12h + humus and the control group. Subsequently, new sources of seedling explants were obtained in studies of tissue culture. Laboratory of Plant Biotechnology that the university, was used stem apex, nodal segments and internodes in search of decontamination with various concentrations of calcium hypochlorite [Ca(OCl)2] and micropropagation, inoculating them in half WPM (1980) with various concentrations of 6-benzylaminopurine (BAP). We used 10 sample units with three replications for different concentrations of [Ca(OCl)2], BAP and explants type. After thirty days, which was observed for the control of contamination, during the establishment in vitro, concentrations of [Ca(OCl)2] between 0.5% and 2.0% were effective in combating exogenous contamination of the apex. In nodal segments and internodes, concentrations of [Ca(OCl)2] between 1.0% and 2.0% and 1.5% and 2.0% were respectively, sufficient to reduce the percentage of losses in these infestations explants. For micropropagation, the culture medium supplemented with 0.1 mg.L-1 BAP promotes better development of multiple shoots per explants from nodal segment. However, success does not get to shoot training in internodal segment
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The objective of this study of comparative descriptive character went aimed at to analyze the characteristics dermatoglyphics, anthropometrics and the basic physical qualities, in 180 selected scholars in a stratified way, distributed like this: 10 year-old boys = 32; 09 years = 32; 08 years = 32; 10 year-old girls = 28; 09 years = 28; 08 years = 28), studying the fundamental teaching of the School Good Municipal Hope, located in the area east, in the Neighborhood of the Crowned, in the city of Manaus, Amazon. For identification of the dermatoglyphics characteristics collected, was the fingerprints; for evaluation of the corporal mass, height and IMC, they were used a digital scale with an estadiometer of the mark Filizola. The tests: to sit down and to reach flexibility); Horizontal Impulse or I jump in distance stopped (force of inferior members); Flex and extension of the trunk (it Forces abdominal); Flexion and extension of the arms in suspension in the bar (Force of superior members); 30 meters (Speed) and 9 minutes (Resistance applied aerobic) was to evaluate the basic physical qualities. The results demonstrated that differences didn't exist among the goods, in most of the studied variables, and the existent differences among the ages of 8, 9 and 10 years, they demonstrate a normality tendency in the infantile development
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O regime eólico de uma região pode ser descrito por distribuição de frequências que fornecem informações e características extremamente necessárias para uma possível implantação de sistemas eólicos de captação de energia na região e consequentes aplicações no meio rural em regiões afastadas. Estas características, tais como a velocidade média anual, a variância das velocidades registradas e a densidade da potência eólica média horária, podem ser obtidas pela frequência de ocorrências de determinada velocidade, que por sua vez deve ser estudada através de expressões analíticas. A função analítica mais adequada para distribuições eólicas é a função de densidade de Weibull, que pode ser determinada por métodos numéricos e regressões lineares. O objetivo deste trabalho é caracterizar analítica e geometricamente todos os procedimentos metodológicos necessários para a realização de uma caracterização completa do regime eólico de uma região e suas aplicações na região de Botucatu - SP, visando a determinar o potencial energético para implementação de turbinas eólicas. Assim, foi possível estabelecer teoremas relacionados com a forma de caracterização do regime eólico, estabelecendo a metodologia concisa analiticamente para a definição dos parâmetros eólicos de qualquer região a ser estudada. Para o desenvolvimento desta pesquisa, utilizou-se um anemômetro da CAMPBELL.
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The aim of this research was to analyse genetic markers, anthropometry and basic physical qualities in the differret stages of sexual maturation in swimmers in Paraíba. It is characterised as a descriptive cross sectional study. The sample was composed of 119 swimmers (males) that were divided among the stages of sexual maturation, from 7 to 17,9 years of age. They were associated to a local federation, the Confederação Brasileira de Desportes Aquáticos. The tests used were: genetic markers dermatoglyphics; Anthropometry body mass, stature, arm span, fat percentage and somatotype; physical qualities speed tests (25 meters crawl), strength (vertical jump) to inferior limbs, verarm throwing arremesso of a 2kg medicineball to superior limbs and abdominal), resistence (12 minutes to swimming), agility (he multistage 20-meter shuttle run test), flexibility (sit and reach test ) and coodination (stroke index); power of swimming (mean velocity in 25 meters mutiplied by body mass) and the self assessment of the sexual maturation supervised by a pediatric specialist. In the analyses we used the test normality of Shapiro-Wilk, then, we used ANOVA- one way followed by Post-Hoc test of Scheffé. The data showed in dermatogliphics a genetic tendence to velocity (L>W) with a predominance of the meso-ectomorphic somatotype profile; in relation to the physical qualities there was an evolution of the results in every stage due to the antropometric variables, except in the coordination tests. There were no significative differences between the stages. We conclude that swimming in Paraíba is composed of a signicative number of velocists with a mesomorph somatotype profile and low fat percentage, and that made it posssible to us to recomend that the trainings must be individual and according to personal characteristics of each athlete, and that the used variables must be specific for every region of the country. This dissertation presents a relation of multidiciplinar interface and its content has an application in Physical Education and Medicine
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A fase da puberdade é o período em que ocorrem as maiores transformações características da adolescência. Por essa razão, este estudo objetivou identificar o estado nutricional, desempenho motor e marcadores dermatoglíficos em 2363 escolares púberes selecionados de forma estratificada, de ambos os sexos, com idades variando de 6 a 15 anos, matriculados no Ensino Fundamental (2ª a 9ª Séries) do ensino público no estado do Rio Grande do Norte. Foram avaliados o estado nutricional (Índice de Massa Corporal); as qualidades físicas básicas ( testes de coordenação, equilíbrio, agilidade, flexibilidade, força e velocidade); o potencial genético (método da dermatoglifia) e o estágio maturacional (auto avaliação de Tanner); Com relação ao estado nutricional observou-se que escolares acima do peso apresentam valores mais baixos em relação ao seu desempenho motor sendo esses valores, mais significativos nos meninos. No que se refere à maturação sexual, os resultados apontaram que os meninos atingem os estágios maturacionais primeiro que as meninas, não tendo encontrado correlação entre o potencial genético e os demais indicadores o que nos permite concluir que os escolares do estado do Rio Grande do Norte, principalmente os do sexo masculino sofrem influência significativa de seu estado nutricional e seu estágio maturacional no que diz respeito ao seu desempenho motor. Essa dissertação apresenta relação de interdisciplinaridade, tendo o seu conteúdo uma aplicação nos campos da Educação Física, Nutrição, Medicina e Enfermagem.
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Analyze, in patients with primary hyperhidrosis (PH) who was undergone to videothoracoscopic sympathicotomy, the degree of vascular denervation after surgical transection of the thoracic sympathetic chain by measuring ultrasonografic parameters in carotid and vertebral arteries. Methods: Twenty-four patients with PH underwent forty-eight endoscopic thoracic sympathicotomy and were evaluated by duplex eco-doppler measuring systolic peak velocity (SPV), diastolic peak velocity (DPV), pulsatility index (PI) and resistivity index (RI) in bilateral common, internal and external carotids, besides bilateral vertebral arteries. The exams were performed before operations and a month later. Wilcoxon test was used to analyse the differences between the variables before and after the sympatholisis. Results: T3 sympathicotomy segment was the most frequent transection done (95,83%), as only ablation (25%) or in association with T4 (62,50%) or with T2 (8,33%). It was observed increase in RI and PI of the common carotid artery ( p<0,05). The DPV of internal carotid artery decreased in both sides (p<0,05). The SPV and the DPV of the right and left vertebral arteries also increased (p<0,05). Asymmetric findings were observed so that, arteries of the right side were the most frequently affected. Conclusions: Hemodynamic changes in vertebral and carotid arteries were observed after sympathicotomy for PH. SPV was the most often altered parameter, mostly in the right side arteries, meaning significant asymmetric changes in carotid and vertebral vessels. Therefore, the research findings deserve further investigations to observe if they have clinical inferences
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Objective: The aim of the study was to investigate physical characteristics and to examine association between somatotype and performance in collegiate runners of 100 m and 400 m. Methods: The sample, male runners (n=39) competing at the regional level in the state of Rio Grande do Norte, Brazil, had height, body mass, skinfolds, limb circumference and skeletal breadths measured. Then, the somatotype was calculated by Health-Carter method. Races (100 m and 400 m) were held to assess athletic performance. Descriptive statistics were calculated for the total sample, as well as for the 100 m and 400 m groups, and established four subgroups, named quartiles. For analysis between groups of runners (100 m x 400 m) was used Student's t test for independent samples. To examine the relationship between the race times and anthropometric variables, was used the Pearson correlation test. The somatotype dispersion distance and somatotype spatial distance were calculated among subgroups. One-way analysis of variance, the Wilcoxon test followed of Tukey post test, and correlation analysis were used with a significance level of p<0.05. Results: Somatotype with mesomorphy and ectomorphy dominance was exhibited by 100 m and 400 m athletes. Endomorphy was low in both groups, especially in 400m runners, who had more elongated body types than 100 m runners. When separately compared by athletic performance quartile, 100 m sprinters of better qualifications (G100-G1) had somatotype with dominant mesomorphy, whereas 400 m runners had somatotype with dominant ectomorphy. A significant correlation (r = -0.55, p=0.008) between calf circumference and 100 m race times was observed showing the importance of muscularity, whereas a significant correlation was found between height and 400 m race times (r = -0.53, p=0.02) showing the importance of linearity. Conclusion: Runners of 100 and 400 may show differences in physical characteristics, depending on the level of athletic performance. Anthropometric periodic evaluations may help in the training process of these athletes. However, more specific assessment parameters should be taken into account, because somatotype by itself has not power to predict whether an individual will succeed in racing speed
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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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O objetivo deste estudo foi avaliar o efeito do horário, taxa e freqüência de alimentação no desempenho do matrinxã (Brycon amazonicus) em tanques de cultivo. O trabalho foi realizado no Centro de Aqüicultura da UNESP, Jaboticabal, SP, no período de outubro de 1997 a janeiro de 1998 sendo realizados três ensaios, em tanques de 200m² subdivididos em 4 de 50 m². No ensaio I foram medidos em 3 períodos (manhã-m; meio do dia-md e tarde-t) o consumo de ração, índice de ingestão, tempo de saciação e velocidade de ingestão em peixes com peso médio de 232,13 g, alimentados com ração extrusada (32% de PB). Não foi observada diferença significativa nos parâmetros analisados. No ensaio II, em peixes com peso médio de 233,98 g, foi medido o consumo médio de ração, em intervalos de duas horas, das 07 às 19 horas. O maior consumo ocorreu quando o matrinxã foi alimentado às 17 horas. No ensaio III, durante 57 dias, os peixes foram alimentados uma vez ao dia (m); uma vez ao dia (t); duas vezes ao dia(m/t) e três vezes ao dia (m,md,t). Peixes com peso médio inicial de 322,25 g receberam ração com 32% de PB, na quantidade de 2% do PV. Não foram observadas diferenças significativas no ganho de peso diário (3,17; 2,80; 3,04 e 2,81 g) e na conversão alimentar aparente (2,11; 2,48; 2,16 e 2,31:1). Concluiu-se que a freqüência de alimentação de uma vez ao dia, em qualquer horário, mostrou ser suficiente.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
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condições de saúde são questões que precisam ser investigadas na nossa sociedade. Diante da inexistência de estudos que abordem os aspectos psicológicos e físicos desses profissionais, tornou-se necessário e relevante esta investigação para a área de segurança pública num contexto multidisciplinar. O estudo objetivou verificar as características da aptidão física e psicológica relacionada à saúde de policiais militares do Batalhão de Atividades Policiais Especiais (BOPE), da Polícia Militar do Rio Grande do Norte. A amostra selecionada de forma aleatória foi composta de 64 militares de diferentes graduações, do sexo masculino com idade média de 26,2±2,6 anos. Foram utilizados como instrumentos de medida o Questionário de Saúde Geral de Goldberg para avaliar a saúde geral; uma balança digital da marca Techline®, e estadiômetro portátil da marca Sanny® para avaliar a massa corporal e a estatura; fita antropométrica metálica Sanny® para avaliar a perimetria (circunferência do braço contraído, circunferência da panturrilha); paquímetro Sanny® para avaliar os diâmetros ósseos (bi-epicondilar umeral e bi-epicodilar femural); adipômetro Harpender® para avaliar a espessura das dobras cutâneas; dinamômetro manual Jamar para avaliar a força de preensão manual; flexímetro Sanny®, fotocélulas CEFISE modelo Speed Test Fit e o YoYo Intermitent Recovery Test para avaliar o desempenho físico ( flexibilidade, agilidade, velocidade e endurance anaeróbica). Os participantes apresentaram valores elevados para risco de distúrbio ou mesmo a presença de distúrbio, no que se refere à saúde geral; o grupo estudado é classificado como mesoendomorfico, predominando características de endurance aeróbico e anaeróbico e força que foram relacionadas com os aspectos psicológicos. O perfil somatotípico meso-endomorfo parece interferir nos elevados riscos de distúrbios psicológicos advindos da atividade laboral exigida, apesar dos mesmos apresentarem um bom desempenho físico
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
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The purpose of the present study is to identify the dermatoglyphic and somatotypic characteristics and the physical qualities of athletes from the under-17 State volleyball team, in Rio Grande do Norte, Brazil. The sample was composed of athletes, n = 14, aged 15.0 ± 0.88 years, weight (Kg) 58.3 ± 5.90 and height (cm) 169.4 ± 7.97, members of the referred team. For data collection Cummins & Midlo s (1942), o dermatoglyphic method and Heath & Carter s (1967) somatotypic method were used and to evaluate physical qualities, 2400m, 50m, Shuttle Run, abdominal , Sargent test and medicine-ball toss were performed. Fingerprints show that the group presents genetic predisposition for the following physical qualities: explosive force and velocity. As to somatotype, the group was endo-ectomorphic. At physical evaluation the group presented low Vo2 max values and reasonable levels of explosive force, local muscular endurance, agility and velocity. We conclude that: according to the dermatoglyphic model observed, the group needs training strategies to improve coordination and agility; somatotype reveals the necessity for reducing fat levels and increasing muscular mass; the evaluation of physical qualities demonstrates the need for better physical preparation. This study traces the profile of the under-17 volleyball player from Rio Grande do Norte, with respect to genetic and somatotypic aspects and physical qualities, which will serve as a parameter for future state teams