979 resultados para Experimental program


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Public programs (of disputed effect) offering summer jobs or work while in high school to smooth the transition from school to work is commonplace. In this paper, 1447 girls in their first grade of high school between 1997-2003 and randomly allotted summer jobs via a program in Falun (Sweden) are followed 5-12 years after graduation. The program led to a substantially larger accumulation of income while in high school. The causal effect of the high school income on post-schooling incomes was substantial and statistically significant. The implied elasticity of 0.4 is however potentially inflated dueto heterogeneous effects.

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Nós usamos a metodologia de Regressões em Descontinuidade (RDD) para estimar o efeito causal do Fundo de Participação dos Municípios (FPM) recebido por um município sobre características dos municípios vizinhos, considerando uma variedade de temas: finanças públicas, educação, saúde e resultados eleitorais. Nós exploramos a regra que gera uma variação exógena da transferência em munícipios próximos às descontinuidades no repasse do fundo de acordo com faixas de população. Nossa principal contribuição é estimar separadamente e em conjunto o efeito spillover e o efeito direto do FPM, considerando ambos municípios vizinhos ou apenas um deles próximos às mudanças de faixa. Dessa forma, conseguimos entender melhor a interação entre municípios vizinhos quando há uma correlação na probabilidade de receber uma transferência federal. Nós mostramos que a estimativa do efeito direto do FPM sobre os gastos locais diminui em cerca de 20% quando controlamos pelo spillover do vizinho, que em geral é positivo, com exceção dos gastos em saúde e saneamento. Nós estimamos um efeito positivo da transferência sobre notas na prova Brasil e taxas de aprovação escolares em municípios vizinhos e na rede estadual do ensino fundamental. Por outro lado, o recebimento de FPM por municípios vizinhos de pequena população reduz o provimento de bens e serviços de saúde em cidades próximas e maiores, o que pode ocorrer devido à redução da demanda por serviços de saúde. A piora de alguns indicadores globais de saúde é um indício, no entanto, de que podem existir problemas de coordenação para os prefeitos reterem seus gastos em saúde. De fato, quando controlamos pela margem de vitória nas eleições municipais e consideramos apenas cidades vizinhas com prefeitos de partido diferentes, o efeito spillover é maior em magnitude, o que indica que incentivos políticos são importantes para explicar a subprovisão de serviços em saúde, por um lado, e o aumento da provisão de bens em educação, por outro. Nós também constatamos um efeito positivo do FPM sobre votos para o partido do governo federal nas eleições municipais e nacionais, e grande parte desse efeito é explicado pelo spillover do FPM de cidades vizinhas, mostrando que cidades com dependência econômica do governo federal se tornam a base de sustentação e apoio político desse governo. Por fim, nós encontramos um efeito ambíguo do aumento de receita devido ao FPM sobre a competição eleitoral nas eleições municipais, com uma queda da margem de vitória do primeiro colocado e uma redução do número de candidatos, o que pode ser explicado pelo aumento do custo fixo das campanhas locais.

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The protective effect of various Salmonella vaccines regimens against an experimental Salmonella Gallinarum challenge (SGNalr strain at 12 wk of age) was evaluated in two experiments. In Experiment 1 commercial brown layers were vaccinated according to one of the following programs: (i) two doses of a SE bacterin (Layermune SE; group 1); (ii) a first dose of a live SG9R vaccine (Cevac SG9R) followed by a SE bacterin (Layermune SE; group 2); (iii) one dose of each of two different multivalent inactivated vaccines containing SE cells (Corymune 4 & Corymune 7; group 3) or (iv) not vaccinated (group 4). In Experiment 2, broiler breeders were given the same vaccination treatments except for the group vaccinated with the multivalent vaccines. Overall, in both experiments, all vaccination schemes were effective in reducing mortality after challenge with a SG field strain. Primary vaccination with an initial dose of a live SG9R vaccine followed some weeks later by a dose of an inactivated SE bacterin was the most effective (p<0.05) vaccination program against mortality induced by field SG experimental challenge in both experiments. In conclusion, Salmonella vaccination programs containing SE bacterins alone or in combination with a live SG9R vaccine are effective in preventing mortality induced by infection of field SG. Nevertheless, it is important to emphasize that any vaccination program against any Salmonella serotype will only be effective if it is part of a sound and comprehensive biosecurity program designed for Salmonella control in poultry farms.

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The present work had as objective to apply an experimental planning aiming at to improve the efficiency of separation of a new type of mixer-settler applied to treat waste water contaminated with oil. An unity in scale of laboratory, was installed in the Post-graduation Program of Chemical Engineering of UFRN. It was constructed in partnership with Petrobras S.A. This called device Misturador-Decantador a Inversão de Fases (MDIF) , possess features of conventional mixer-settler and spray column type. The equipment is composed of three main parts: mixing chamber; chamber of decantation and chamber of separation. The efficiency of separation is evaluated analyzing the oil concentrations in water in the feed and the output of the device. For the analysis one used the gravimetric method of oil and greases analysis (TOG). The system in study is a water of formation emulsified with oil. The used extractant is a mixture of Turpentine spirit hydro-carbons, supplied for Petrobras. It was applied, for otimization of the efficiency of separation of the equipment, an experimental planning of the composite central type, having as factorial portion fractionary factorial planning 2 5-2, with the magnifying of the type star and five replications in the central point. In this work, the following independents variables were studied: contents of oil in the feed of the device; volumetric ratio (O/A); total flowrate ; agitation in the mixing chamber and height of the organic bed. Minimum and maximum limits for the studied variables had been fixed according previous works. The analysis of variance for the equation of the empirical model, revealed statistically significant and useful results for predictions ends. The variance analysis also presented the distribution of the error as a normal distribution and was observed that as the dispersions do not depend on the levels of the factors, the independence assumption can be verified. The variation around the average is explained by 98.98%, or either, equal to the maximum value, being the smoothing of the model in relation to the experimental points of 0,98981. The results present a strong interaction between the variable oil contents in the feed and agitation in the mixing chamber, having great and positive influence in the separation efficiency. Another variable that presented a great positive influence was the height of the organic bed. The best results of separation efficiency had been obtained for high flowrates when associates the high oil concentrations and high agitation. The results of the present work had shown excellent agreement with the results carried out through previous works with the mixer-settler of phase inversion

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Our aim was to investigate the effects of an aerobic training program on adverse and early left ventricle (LV) remodeling, using an experimental model of short-term type 1 diabetes (T1D). Wistar rats were divided in 4 groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD) and trained diabetic (TD). T1D was induced by streptozotocin (45 mg/kg). The training program consisted of 4 weeks running on a treadmill (13 m/min, 60 min/day, 5 days/week). At the end of the experiments, hearts were collected for analysis of morphology and transcriptional profile of LV, by focusing on its remodeling. Deaths were recorded during the 4-week period. We verified high mortality among animals of DS group, whereas it was significantly reduced in DT group. DS group also showed an increase in cross-sectional area of cardiomyocytes and fibrosis. TD group exhibited reduction in measures of cardiac trophism, but with respect to collagen content, it was similar to CS group. Analysis of gene expression related to cardiac remodeling revealed decreased expression of collagen I and III, as well as low expression of MMP-2 in DS group. TD group showed decreased levels of mRNA for MMP-9, and unchanged gene expression of MMP-2 when compared with the CS group. The expression of MMP-2 and TGF-1 were increased in CT group. The ratio between gene expression of collagen I and III was increased in the CT group and decreased in diabetic groups. These results establish early changes of the structure and transcriptional profile of LV myocardium. Moreover, they indicate that aerobic exercise training plays specific protection against mechanisms responsible for cardiac damage observed in T1D

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The objective of this paper is the numerical study of the behavior of reinforced concrete beams and columns by non-linear numerical simulations. The numerical analysis is based on the finite element method implemented in CASTEM 2000. This program uses the constitutive elastoplastic perfect model for the steel, the Drucker-Prager model for the concrete and the Newton-Raphson for the solution of non-linear systems. This work concentrates on the determination of equilibrium curves to the beams and force-strain curves to the columns. The numeric responses are confronted with experimental results found in the literature in order to check there liability of the numerical analyses.

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O objetivo da presente investigação experimental foi avaliar o perfil mecânico de três tipos de técnicas de sutura entre tendões de dimensões diferentes. Foram utilizados 21 cães sem raça definida (11machos/10 fêmeas), dos quais foram obtidos os tendões flexor comum dos dedos - t.c. (maior dimensão) e tibial cranial - t.cr. (menor dimensão), de ambos os membros pélvicos. Logo após a obtenção das peças foi realizada sutura, segundo cada tipo de técnica, porém sempre com o mesmo número de pontos. Os tendões utilizados para sutura foram sempre do lado direito e o controle do lado esquerdo (t.cr.). Após a sutura, os corpos de prova foram fixados em garras especialmente desenvolvidas e submetidos a ensaio de tração axial à velocidade de 30mm/minuto. Após o ensaio o programa da máquina forneceu os valores da carga máxima ( na ruptura) e deformação absoluta (mm) e relativa (%), além do diagrama carga-deformação. Os resultados foram submetidos a estudo estatístico pela análise de medidas repetidas no nível de 5% de significância. Não foi constatada diferença estatisticamente significativa nos parâmetros mecânicos avaliados nos três grupos de técnicas de suturas. em relação ao controle (tendão de menos diâmetro contra-lateral), observou-se que a sutura apresenta resistência máxima a tração significativamente menor que o controle e maior deformação.

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Background: Ageing is characterized by a number of physical changes that contribute to a decline in the ability to perform daily tasks. Stretching has been proposed to reduce hip flexion contracture and increase hip and pelvis range of motion, thus improving gait performance. Objective: The purpose of this study was to determine whether a supervised stretching program designed to improve the range of motion of the lower limbs alters gait kinematics in older adults. Methods: Twenty healthy older adult women (65.9 +/- 4.2 years old and BMI 24.9 +/- 3.5) were divided into 2 groups. The experimental group undertook 12 sessions of stretching exercises, whereas the control group did not engage in any physical activity. Gait performance was assessed at the beginning of the experiment and after the 4-week intervention period. Results: Those in the experimental group showed increased step length, higher velocity and reduced double support time after training. In addition, participants involved in the stretching program showed greater anterior and lateral pelvis tilt and also greater rotation (p < 0.05). Conclusions: Based on our results, we can suggest that a supervised stretching program is effective to alter a number of gait variables. Moreover, after the stretching protocol, aged participants displayed gait parameters which were similar to those reported in young healthy adults. Therefore, stretching can be used as an effective means to improve range of motion and reverse some age-related changes that influence gait performance. Copyright (C) 2009 S. Karger AG, Basel

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Disordered and crystalline Ba0.45Sr0.55TiO3 (BST) powder processed at low temperature was synthesized by the polymeric precursor method. The single-phase perovskite structure of the ceramics was identified by the Raman and X-ray diffraction techniques. Photoluminescence at room temperature was observed only in a disordered BST sample. Increasing the calcination time intensified the photoluminescence (PL), which reached its maximum value in the sample heat treated at 300 degrees C for 30 h. This emission may be correlated with the structural disorder. Periodic ab initio quantum-mechanical calculations using the CRYSTAL98 program can yield important information regarding the electronic and structural properties of crystalline and disordered solids. The experimental and theoretical results indicate the presence of intermediary energy levels in the band gap. This is ascribed to the break in symmetry, which is responsible for visible photoluminescence in the material's disordered state at room temperature. (c) 2005 Elsevier B.V. All rights reserved.

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Sm-doped PbTiO3 powder was synthesized by the polymeric precursor method, and was heat treated at different temperatures. The x-ray diffraction, photoluminescence, and UV-visible were used as a probe for the structural order degree short-, intermediate-, and long-range orders. Sm-3+ ions were used as markers of these order-disorder transformations in the PbTiO3 system. From the Rietveld refinement of the Sm-doped PbTiO3 x-ray diffraction data, structural models were obtained and analyzed by periodic ab initio quantum mechanical calculations using the CRYSTAL 98 package within the framework of density functional theory at the B3LYP level. This program can yield important information regarding the structural and electronic properties of crystalline and disordered structures. The experimental and theoretical results indicate the presence of the localized states in the band gap, due to the symmetry break, which is responsible for visible photoluminescence at room temperature in the disordered structure. (c) 2006 American Institute of Physics.

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Reactive zirconia powder was synthesized by the complexation of zirconium metal from zirconium hydroxide using a solution of 8-hydroxiquinoline. The kinetics of zirconia crystallization was followed by X-ray diffraction, scanning electron microscopy and surface area measured by the nitrogen adsorption/desorption technique. The results indicated that zirconia with a surface area as high as 100 m(2)/g can be obtained by this method after calcination at 500degreesC. Zirconia presents three polymorphic phases (monoclinic, tetragonal and cubic), which are reversibly interconversible. The cluster model Zr4O8 and Z(r)4O(7)(+2) was used for a theoretical study of the stabilization process. The ab initio RHF method was employed with the Gaussian94 program and the total energies and the energy gap of the different phases were calculated and compared with the experimental energy gap. The theoretical results show good reproducibility of the energy gap for zirconia. (C) 2004 Kluwer Academic Publishers.

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The purpose of the study was to evaluate the blood serum components and histopathological findings of commercial layers experimentally infected with Salmonella Gallinarum (SG), the microorganism responsible for the fowl typhoid. 180 commercial layers were distributed into three groups (G): G1 and G2 received 0.2mL of inoculum containing 3.3x10 8 and 3.3x10 5 CFU of resistant SG to the nalidix acid (Nal r)/mL, respectively, directly into their crops; G3 did not receive the inoculum (control group). The birds were inoculated when they were 5 days old and the euthanasia was performed 24 hours before and after infection and 3, 5, 7 and 10 days after the administration of the inoculum. In each day of collection, blood samples were obtained for biochemical tests of the blood serum besides macroscopic and histopathological examination of the birds. Data were submitted to analysis of variance by the SAS statistical program and the means were compared by Tukeýs test (P<0,05). In the serum biochemical profile it was observed that the infection interfered in the values of total protein, albumin, calcium, phosphorus, cholesterol, triglycerides, GGT and ALT in the infected groups. The macroscopic examination showed hepatomegaly, alteration of the hepatic color and hemorrhagic spots in the kidneys of animals from G1. The histopathology showed degeneration of hepatocytes in G1 and G2 although other lesions like multifocal hepatic necrosis and inflammatory infiltrate on the liver and kidneys were restricted to G1. The alterations were more evident on G1 which received a higher concentration of bacteria/mL when compared to G2. The results showed that the correlation between biochemical alterations and macroscopic and histopathological lesions can assist the comprehension of the pathophysiology of fowl typhoid, supplying important information for the diagnosis and prognosis of this disease.

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The objective of this study was to conduct a systematic review of studies that analyzed the effect of physical exercise on the peripheral levels of BDNF in elderly individuals. Method: We conducted a search in PsycINFO, Biological Abstracts, Pubmed, Web of Science, and Science Direct from 1990 to 2011, using the following keywords: physical exercise , physical activity , physical therapy , training , BDNF , neuroplasticity , neurotrophins , neuroplasticity proteins , aged , older , elderly The articles were considered for inclusion in the review if they were studies with elderly, assessed peripheral (serum and/or plasma) BDNF and evaluated an acute exercise or chronic exercise (training). Results: Five randomized controlled trial and one randomized non-controlled trial studies were analyzed. Five out of six studies reported a significantly higher BDNF response to aerobic acute exercise and to aerobic or strength training program in healthy elderly and elderly with different pathologies. Conclusion: It was not possible to establish a recommendation protocol for the type and intensity of physical exercise required to produce an increase in levels BDNF. However, physical exercise, particularly, moderate-intensity exercises seem to be more effective to promote increase the peripheral levels of BDNF in the elderly. © 2012 Elsevier B.V.

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Pós-graduação em Engenharia Mecânica - FEIS