947 resultados para Elasticity of output with respect to factors


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Researches on control for power electronics have looked for original solutions in order to advance renewable resources feasibility, specially the photovoltaic (PV). In this context, for PV renewable energy source the usage of compact, high efficiency, low cost and reliable converters are very attractive. In this context, two improved simplified converters, namely Tri-state Boost and Tri-state Buck-Boost integrated single-phase inverters, are achieved with the presented Tri-state modulation and control schemes, which guarantees the input to output power decoupling control. This feature enhances the field of single-phase PV inverters once the energy storage is mainly inductive. The main features of the proposal are confirmed with some simulations and experimental results. © 2012 IEEE.

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Objective The purpose of this study was to identify the clinical factors associated with time to hCG remission among women with low-risk postmolar GTN. Methods This study included a non-concurrent cohort of 328 patients diagnosed with low-risk postmolar GTN according to FIGO 2002 criteria. Associations of time to hCG remission with history of prior mole, molar histology, time to persistence, use of D&C at persistence, presence of metastatic disease, FIGO score, hCG values at persistence, type of first line therapy and use of multiagent chemotherapy were investigated with both univariate and multivariate analyses. Results Overall median time to remission was 46 days. Ten percent of the patients required multi-agent chemotherapy to achieve hCG remission. Multivariate analysis incorporating the variables significant on univariate analysis confirmed that complete molar histology (HR 1.45), metastatic disease (HR 1.66), use of multi-agent therapy (HR 2.00) and FIGO score (HR 1.82) were associated with longer time to remission. There was a linear relationship between FIGO score and time to hCG remission. Each 1-point increment in FIGO score was associated with an average 17-day increase in hCG remission time (95% CI: 12.5-21.6). Conclusions Complete mole histology prior to GTN, presence of metastatic disease, use of multi-agent therapy and higher FIGO score were independent factors associated with longer time to hCG remission in low-risk GTN. Identifying the prognostic factors associated with time to remission and effective counseling may help improve treatment planning and reduce anxiety in patients and their families. © 2013 Elsevier Inc. All rights reserved.

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Introduction There is a renewed call for a new approach to development with emphasis on community empowerment or participation, with the belief that more sustainable activities will be undertaken in those communities. Much of that call, however, is coming not from within the communities, but primarily from advocates of change who may have little to do with those communities. What then will the new approach bring apart from a change in who are the decision-makers? And how do we ensure that the change that is called for will, in fact, bring added benefits to the communities themselves? To be sure, there are some successful stories of a community approach to problem solving. However, there are also many more stories of project failures. Serious analytical work, therefore, needs to be done to determine the factors that promote a successful community-based approach; when this approach should be used; and the methodology that should be employed. In an attempt to determine these factors, a brief analysis will be made of some of the governing structures in the subregion and their possible impact on the proposed new approach. Some of the earlier efforts at stakeholder and community approach to projects will also be examined as well as the new development strategy that is prompting the call for this new paradigm. The new paradigm focuses to a large extent on decision-making and community empowerment. With few exceptions, it is short on the promotion of tangible activities that are based on the resource inventory of the communities. This is not surprising, since, as noted before, the advocates of community empowerment may have very little connection with the communities and, in most cases, are unfamiliar with the resource base. Hence, a theoretical case is made, suggesting more style than substance. Another obvious shortcoming of this new paradigm is its continued over- dependence on assistance from the outside to build communities. Externally funded projects, seminars and meetings outside of the communities and foreign technical assistance continue to dominate these projects. While, of course, all communities have basic common needs such as water, health, education and electricity, there is sufficient diversity within communities to allow for tailoring of activities and programmes such that their differences become assets. It is in that context, that agro-tourism activities, standards, agricultural diversification, food and nutrition and priority setting have been chosen as aspects and activities for promoting community development, drawing on the various strengths of communities, rural or urban.

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ABSTRACT: Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-CAsp80 gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-CAsp80 (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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This work aimed to compare the predictive capacity of empirical models, based on the uniform design utilization combined to artificial neural networks with respect to classical factorial designs in bioprocess, using as example the rabies virus replication in BHK-21 cells. The viral infection process parameters under study were temperature (34°C, 37°C), multiplicity of infection (0.04, 0.07, 0.1), times of infection, and harvest (24, 48, 72 hours) and the monitored output parameter was viral production. A multilevel factorial experimental design was performed for the study of this system. Fractions of this experimental approach (18, 24, 30, 36 and 42 runs), defined according uniform designs, were used as alternative for modelling through artificial neural network and thereafter an output variable optimization was carried out by means of genetic algorithm methodology. Model prediction capacities for all uniform design approaches under study were better than that found for classical factorial design approach. It was demonstrated that uniform design in combination with artificial neural network could be an efficient experimental approach for modelling complex bioprocess like viral production. For the present study case, 67% of experimental resources were saved when compared to a classical factorial design approach. In the near future, this strategy could replace the established factorial designs used in the bioprocess development activities performed within biopharmaceutical organizations because of the improvements gained in the economics of experimentation that do not sacrifice the quality of decisions.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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

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This paper shows the application of a hysteretic model for the Magnetorheological Damper (MRD) placed in the plunge degree-of-freedom of aeroelastic model of a wing. This hysteretic MRD model was developed by the researchers of the French Aerospace Lab. (ONERA) and describe, with a very good precision, the hysteretic behavior of the MRD. The aeroelastic model used in this paper do not have structural nonlinearities, the only nonlinearities showed in the model, are in the unsteady flow equations and are the same proposed by Theodorsen and Wagner in their unsteady aerodynamics theory; and the nonlinearity introduced by the hysteretic model used. The main objective of this paper is show the mathematical modeling of the problem and the equations that describes the aeroelastic response of our problem; and the gain obtained with the introduction of this hysteretic model in the equations with respect to other models that do not show the this behavior, through of pictures that represents the time response and Phase diagrams. These pictures are obtained using flow velocities before and after the flutter velocity. Finally, an open-loop control was made to show the effect of the MRD in the aeroelastic behavior.

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A mathematical model is developed for an irreversible Brayton cycle with regeneration, inter-cooling and reheating. The irreversibility are from the thermal resistance in the heat exchangers, the pressure drops in pipes, the non-isentropic behavior in the adiabatic expansions and compressions and the heat leakage to the cold source. The cycle is optimized by maximizing the ecological function, which is achieved by the search for optimal values for the temperatures of the cycle and for the pressure ratios of the first stage compression and the first stage expansion. The advantages of using the regenerator, intercooler and reheater are presented by comparison with cycles that do not incorporate one or more of these processes. Optimization results are compared with those obtained by maximizing the power output and it is concluded that the point of maximum ecological function has major advantages with respect to the entropy generation rate and the thermal efficiency, at the cost of a small loss in power.

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Decentralization and regionalization represent constitutional guidelines for the organization of the Unified Health System, which in the last 20 years has required the adoption of mechanisms to coordinate and accommodate federative tensions in Brazil's healthcare sector. This paper analyzes the national implementation of the Health Pact between 2006 and 2010 involving a strategy that reconfigures intergovernmental relations in the sector. The study involved the analysis of documents, official data and interviews with federal, state and municipal managers in the Brazilian states. The content of the national proposal is initially discussed, including its implications for health policy. The different rhythms and degrees of implementation of the Health Pact are then reviewed, with respect to adherence by states and municipalities and the formation of Regional Management Boards. Lastly, the conditioning factors for the multiplicity of experiences observed in the country are identified and the challenges facing progress toward a decentralized and regionalized health system in Brazil are discussed.

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There are several techniques to characterize the elastic modulus of wood and those currently using the natural frequencies of vibration stand out as they are non-destructive techniques, producing results that can be repeated and compared over time. This study reports on the effectiveness of the testing methods based on the natural frequencies of vibration versus static bending to obtain the elastic properties of reforested structural wood components usually employed in civil construction. The following components were evaluated: 24 beams of Eucalyptus sp. with nominal dimensions (40 x 60 x 2.000 mm) and 14 beams of Pinus oocarpa with nominal dimensions (45 x 90 x 2.300 mm) both without treatment; 30 boards with nominal dimensions (40 x 240 x 2.010 mm) and 30 boards with nominal dimensions (40 x 240 x 3.050 mm), both of Pinus oocarpa and with chromate copper arsenate (CCA) preservative treatment. The results obtained in thiswork show good correlation when compared to the results obtained by the static bending mechanical method, especially when applying the natural frequency of longitudinal vibration. The use of longitudinal frequency was reliable and practical, therefore recommended for determining the modulus of elasticity of wood structural elements. It was also found that no specific support is needed for the specimens using the longitudinal frequency, as well as no previous calibrations, reducing the execution time and enabling to test many samples.