986 resultados para Sidney, Algernon, 1623-1683.


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O objetivo deste trabalho foi analizar a distribuição espacial da compactação do solo e a influência da umidade do solo na resistência à penetração. Esta última variável foi descrita pelo índice de cone. O solo estudado foi Nitossolo e os dados de índice de cone foram obtidos usando um penetrômetro. A resistência do solo foi avaliada a 5 profundidades diferentes, 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm e mais de 40 cm, porém o conteúdo de umidade do solo foi medido a 0-20 cm e 20-40 cm. As condições hídricas do solo variaram nas diferentes amostragems. Os coeficientes de variação para o índice de cone foram 16,5% a 45,8% e os do conteúdo de umidade do solo variaram entre 8,96% e 21,38%. Os resultados sugeriram elevada correlação entre a resistência do solo, estimada pelo índice de cone e a profundidade do solo. Sem embargo, a relação esperada com a umidade do solo não foi apreciada. Observou-se dependência espacial em 31 de 35 séries de dados de índice de cone e umidade do solo. Esta dependência foi ajustada por modelos exponenciais com efeito pepita variável de 0 a 90% o valor do patamar. em séries de dados o comportamento foi aleatório. Portanto, a técnica das distâncias inversas foi utilizada para cartografar a distribuição das variáveis que não tiveram estrutura espacial. Na krigagem constatou-se uma suavização dos mapas comparados com esses das distâncias inversas. A krigagem indicadora foi utilizada para cartografar a variabilidade espacial do índice de cone e recomendar melhor manejo do solo.

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This work proposes a computational methodology to solve problems of optimization in structural design. The application develops, implements and integrates methods for structural analysis, geometric modeling, design sensitivity analysis and optimization. So, the optimum design problem is particularized for plane stress case, with the objective to minimize the structural mass subject to a stress criterion. Notice that, these constraints must be evaluated at a series of discrete points, whose distribution should be dense enough in order to minimize the chance of any significant constraint violation between specified points. Therefore, the local stress constraints are transformed into a global stress measure reducing the computational cost in deriving the optimal shape design. The problem is approximated by Finite Element Method using Lagrangian triangular elements with six nodes, and use a automatic mesh generation with a mesh quality criterion of geometric element. The geometric modeling, i.e., the contour is defined by parametric curves of type B-splines, these curves hold suitable characteristics to implement the Shape Optimization Method, that uses the key points like design variables to determine the solution of minimum problem. A reliable tool for design sensitivity analysis is a prerequisite for performing interactive structural design, synthesis and optimization. General expressions for design sensitivity analysis are derived with respect to key points of B-splines. The method of design sensitivity analysis used is the adjoin approach and the analytical method. The formulation of the optimization problem applies the Augmented Lagrangian Method, which convert an optimization problem constrained problem in an unconstrained. The solution of the Augmented Lagrangian function is achieved by determining the analysis of sensitivity. Therefore, the optimization problem reduces to the solution of a sequence of problems with lateral limits constraints, which is solved by the Memoryless Quasi-Newton Method It is demonstrated by several examples that this new approach of analytical design sensitivity analysis of integrated shape design optimization with a global stress criterion purpose is computationally efficient

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O estudo foi conduzido com o objetivo de avaliar a seletividade de alguns herbicidas inibidores de ALS e FS II aplicados em pós-emergência em plantas de Brachiaria brizantha cv. Marandu e Brachiaria decumbens cv. Basilisk em condições de campo e seu efeito na qualidade das sementes. Os herbicidas testados (em g/ha) foram: imazethapyr a 100; chlorimuronethyl a 15; nicosulfuron a 50; bentazon a 720; e atrazine a 3.000, além de uma testemunha, sem aplicação de herbicidas. Dois experimentos em campo foram instalados em delineamento em blocos casualizados com quatro repetições e os ensaios de laboratório em delineamento inteiramente casualizado, com 16 repetições. Todos os herbicidas testados tiveram algum efeito de fitointoxicação visual aos cultivares avaliados. O nicosulfuron foi o herbicida que visualmente proporcionou os níveis mais elevados de injúrias às plantas de B. decumbens e B. brizantha. A produção de MS de B. brizantha nos estádios iniciais de crescimento foi reduzida pelos herbicidas nicosulfuron e atrazine, enquanto, em B. decumbens, apenas o herbicida nicosulfuron ocasionou redução da produção de MS. A qualidade das sementes de ambos os cultivares foi afetada pelo nicosulfuron, que induziu a dormência em sementes de B. decumbens, reduziu a porcentagem de sementes normais e, assim como o atrazine, aumentou a porcentagem de sementes mortas.

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Objectives: Assess the effect of re-expansive respiratory patterns associated to respiratory biofeedback (RBF) on pulmonary function, respiratory muscle strength and habits in individuals with functional mouth breathing (FMB).Methods: Sixty children with FMB were divided into experimental and control groups. The experimental group was submitted to 15 sessions of re-expansive respiratory patterns associated to RBF (biofeedback pletsmovent; MICROHARD (R) V1.0), which provided biofeedback of the thoracic and abdominal movements. The control group was submitted to 15 sessions using biofeedback alone. Spirometry, maximum static respiratory pressure measurements and questions regarding habits (answered by parents/guardians) were carried out before and after therapy. The Student's t-test for paired data and non-parametric tests were employed for statistical analysis at a 5% Level of significance.Results: Significant changes were found in forced vital. capacity, Tiffeneau index scores, maximum expiratory pressure, maximum inspiratory pressure and habits assessed in FMB with the use of RBF associated to the re-expansive patterns. No significant differences were found comparing the experimental and control groups.Conclusions: The results allow the conclusion that RBF associated to re-expansive patterns improves forced vital capacity, Tiffeneau index scores, respiratory muscle strength and habits in FMB and can therefore be used as a form of therapy for such individuals. (C) 2008 Elsevier B.V. All rights reserved.

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Introduction: The proprioceptive neuromuscular facilitation technique (PNF) has been proven to be efficient, since it was found higher gain of joint range-of-motion compared to the classic stretching. This study aimed to perform a comparison between the muscular stretching techniques and the PNF hold-relax on the internal and external sagittal/diagonal plane.Method: Randomly divided in 3 groups by a drawing, 30 healthy male individuals have undergone the test. In group I the hold-relax technique was utilized on the sagittal plane, grupo II receveid hold-relax on the internal and external diagonals, and group III, on which an evaluation was performed, worked as control. All the groups went through tests on the first, fifth and fifteenth day after the application of the different approaches. In this evaluation it was used a Flexis (R) Fleximeter.Result: Group II (diagonal) obtained statistically significant gain of 13.99% in the immediate post-test and post test later obtained a loss of 4.81%, group I (sagittal) showed no statistical difference as the group III (control).Conclusion: We conclude that the technique of PNF in the diagonal plane is effective in the flexibility of the hamstring muscles.

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

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Photoluminescence data of Eu-doped SnO(2) xerogels are presented, yielding information on the symmetry of Eu(3+) luminescent centers, which can be related to their location in the matrix: at lattice sites, substituting to Sn(4+), or segregated at particles surface. Influence of doping concentration and/or particle size on the photoluminescence spectra obtained by energy transfer from the matrix to Eu(3+) sites is investigated. Results show that a better efficiency in the energy transfer processes is obtained for high symmetry Eu(3+) sites and low doping levels. Emission intensity from (5)D(0) -> (7)F(1) transition increases as the temperature is raised from 10 to 240 K, under excitation at 266 nm laser line, because in this transition the multiphonon emission becomes significant only above 240 K. As an extension of this result, we predict high effectiveness for room temperature operation of Eu-based optical communication devices. X-ray diffraction data show that the impurity excess inhibits particle growth, which may influence the asymmetry ratio of luminescence spectra.

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Currently, high-strength materials, particularly AISI 4340 steel, are used in several landing gear components. Due to the high resistance to wear and corrosion required, the components are usually coating by hard chromium. This treatment produces waste, such as Cr+ 6 (hexavalent chromium), generally after applying the coating of hard chromium which is harmful to health and the environment. The process HVOF (High-velocity-oxygen-fuel) is considered a promising technique for deposition of hard chromium alternative coatings, for example, coatings based on tungsten carbide. This technique provides high hardness and good wear strength and more resistance to fatigue when compared to AISI 4340 hard chromium coated. To minimize loss fatigue due to the process of deposition, shot peening is used to obtain a compressive residual stress. The aim of this study was to analyze the effects of the tungsten carbide thermal spray coating applied by the HVOF, in comparison to the conventional hard chromium electroplating on the AISI 4340 high strength steel behavior in fatigue. Optical microscopy and scanning electron microscopy were used to observe crack origin sites, thickness and adhesion of the coating. (C) 2010 Published by Elsevier Ltd.

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We report the effect of solvent on the rhodamine 6G encapsuled into channels of mesoporous silica, synthesized by two-step process that gives intermediary stable hybrid micelles. Mesoporous materials have been obtained by the method that involves surfactant micelles (mainly cationic) and inorganic precursor of the structure to be obtained. MSU-X type mesoporous silica has been synthesized with polyethylene oxide surfactant as the directing-structure agent and tetraethyl orthosilicate Si(OEt)(4) as the silica source. The influence of the solvent on the encapsulation of rhodamine dye was systematically explored, specially its influence on the luminescence properties. Rhodamine 6G encapsuled into mesoporous silica channel was characterized by UV-Vis and luminescence spectroscopies, scanning electron microscopy, small angle x ray scattering and N(2) sorption-desorption. The pore size and the solvent effects into luminescence dye encapsuled into mesoporous silica channels are observed in the visible absorption and emission spectra of rhodamine 6G. The intense photo luminescence band of rhodamine 6G dye is in 500 to 600 nm region. The observed shift of the absorption and emission bands can be assigned to the effect of the solvents dielectric constant and pore size of mesoporous silica.

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Background: The autonomic dysfunction stands out among the complications associated to diabetes mellitus (DM) and may be evaluated through the heart rate variability (HRV), a noninvasive tool to investigate the autonomic nervous system that provides information of health impairments and may be analyzed by using linear and nonlinear methods. Several studies have shown that HRV measured in a linear form is altered in DM. Nevertheless, a few studies investigate the nonlinear behavior of HRV. Therefore, this study aims at gathering information regarding the autonomic changes in subjects with DM identified by nonlinear analysis of HRV.Methods: For that, searches were performed on Medline, SciELO, Lilacs and Cochrane databases using the crossing between the key-words: diabetic autonomic neuropathy, autonomic nervous system, diabetes mellitus and heart rate variability. As inclusion criteria, articles published on a period from 2000 to 2010 with DM type land type II population which assessed the autonomic nervous system by nonlinear indices HRV were considered.Results: The electronic search resulted in a total of 1873 references with the exclusion of 1623 titles and abstracts and from the 250 abstracts remaining, 8 studies were selected to the final analysis that completed the inclusion criteria.Conclusions: In general, the analysis showed that the nonlinear techniques of HRV allowed detecting autonomic changes in DM. The methods of nonlinear analysis are indicated as a possible tool to be used for early diagnosis and prognosis of autonomic dysfunction in DM.

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OBJETIVO: Comparar a eficácia e segurança da profilaxia com heparina de baixo peso molecular (enoxaparina) versus heparina não fracionada (HNF). MÉTODOS: Setenta e cinco pacientes (59 homens e 16 mulheres ), submetidos a amputação maior dos membros inferiores (30 acima do joelho e 45 abaixo do joelho ), foram tratados ao acaso com HNF subcutânea (5,000 IU -2x/dia ) ou enoxaparina subcutânea (40mg/dia ) durante a hospitalização . A profilaxia teve início 12 horas antes da cirurgia ou , em casos emergenciais , no primeiro dia de pós-operatório. RESULTADOS: Os dois grupos de tratamento foram comparáveis em termos de características gerais . A avaliação da TVP foi feita por meio de exame clínico diário e pelo mapeamento dúplex antes e 5-8 dias após a cirurgia . A TVP foi documentada no lado operado em 9,75% dos pacientes tratados com enoxaparina e em 11,76% dos pacientes tratados com HNF (p=0,92) e houve um caso de TVP bilateral em cada grupo . Sangramentos não foram verificados nos 2 grupos . CONCLUSÃO: A enoxaparina e HNF foram igualmente eficientes e seguras para a profilaxia da TVP em pacientes submetidos à amputação de membros inferiores .

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Web services are computational solutions designed according to the principles of Service Oriented Computing. Web services can be built upon pre-existing services available on the Internet by using composition languages. We propose a method to generate WS-BPEL processes from abstract specifications provided with high-level control-flow information. The proposed method allows the composition designer to concentrate on high-level specifi- cations, in order to increase productivity and generate specifications that are independent of specific web services. We consider service orchestrations, that is compositions where a central process coordinates all the operations of the application. The process of generating compositions is based on a rule rewriting algorithm, which has been extended to support basic control-flow information.We created a prototype of the extended refinement method and performed experiments over simple case studies

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Inadequate dialysis causes accumulation of toxic residues that may lead to the development of dialysis-associated pericardial effusion, but several other factors could be associated with this abnormality. The purpose of this study was to evaluate clinical risk factors to asymptomatic pericardial effusion in peritoneal dialysis.This cross-sectional study included 34 patients aged a parts per thousand yen18 years on peritoneal dialysis for at least 3 months, who showed no symptomatic pericardial effusion, hepatic cirrhosis, neoplasias, lupus or amputations, none in minoxidil use. Asymptomatic pericardial effusion was diagnosed by echocardiography. Risk factors were evaluated by logistic regression and Roc curve. Significance level was set at P < 0.05.Patient age was 51 +/- A 15.9 years. of the 34 patients enrolled, 16 were men and 11 diabetic. Five of them presented pericardial effusion. Logistic regression identifies low hemoglobin level (RR 0.454 CI 95%: 0.225-0.913; P = 0.027), low phase angle (RR 0.236 CI 95%: 0.057-0.984; P = 0.048) and low Kt/V (RR 0.001 CI 95%: 0.0-0.492; P = 0.03) as risk factors to pericardial effusion. Roc curve showed that hemoglobin levels below 12.2 g/dL, Kt/V lower than 1.9 and phase angle lower than 4.5A degrees were the best cutoffs to predict pericardial effusion. Four patients showed these three parameters in the unfavorable range, and all these four patients presented pericardial effusion. The other patient with pericardial effusion had two of these parameters reduced.These findings corroborate the hypothesis that uremia plays a significant role in the pathogenesis of dialysis-associated pericardial effusion.

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