965 resultados para Spira, Francesco, -1548.
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The objective of the present study, developed in a mountainous region in Brazil where many landslides occur, is to present a method for detecting landslide scars that couples image processing techniques with spatial analysis tools. An IKONOS image was initially segmented, and then classified through a Batthacharrya classifier, with an acceptance limit of 99%, resulting in 216 polygons identified with a spectral response similar to landslide scars. After making use of some spatial analysis tools that took into account a susceptibility map, a map of local drainage channels and highways, and the maximum expected size of scars in the study area, some features misinterpreted as scars were excluded. The 43 resulting features were then compared with visually interpreted landslide scars and field observations. The proposed method can be reproduced and enhanced by adding filtering criteria and was able to find new scars on the image, with a final error rate of 2.3%.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Objetivos: os autores mostram a experiência preliminar com o uso do balão térmico para ablação do endométrio em pacientes com queixas de menorragia. Pacientes e Métodos: foram submetidas a este procedimento 20 pacientes. Após exame pélvico completo e ultra-sonografia endovaginal, todas as pacientes foram submetidas à histeroscopia diagnóstica com biópsia de endométrio para excluir causas de malignidade. Das 20 pacientes que se submeteram ao tratamento com balão térmico, 16 foram submetidas em regime ambulatorial com anestesia local. O procedimento teve duração de 8 minutos e 30 segundos. Resultados: duas das 20 pacientes mostraram-se insatisfeitas, mantendo o quadro hemorrágico inalterado, e 18 pacientes referiram melhora da sintomatologia. Não houve complicações do procedimento. Conclusões: o uso do balão térmico para ablação endometrial mostrou-se seguro e eficaz para o tratamento da menorragia de causa benigna.
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Paw edema was induced in male Wistar rats (200-250 g) by intraplantar (ipl) administration of 2.5 mu g endotoxin (Etx). Etx, like carrageenin, produced two distinct edema formation phases, an early phase (75 min) followed by a late phase (7 h). We showed that the edema formation in the early phase was antagonized by dipyrone (80 mg/kg, ip) and indomethacin (1 mg/kg, ip) by 52% and 55%, respectively, and that the late phase was resistant to these drugs. These results suggest that in the early phase prostaglandins appear to be involved in the process. However, the activation of the kinin cascade leading to the release of other mediators may be involved in the increase of edema in the late phase. To test this hypothesis, we investigated whether the release of nitric oxide (NO) is involved in the mechanism of endotoxin-induced rat paw edema during the late phase, using N omega-nitro-L-arginine methyl ester (L-NAME) (50 mu g, ipl) as inhibitor of NO synthase and L-arginine (1 mg, ipl) as substrate of NO synthase. The paw edema induced by Etx was inhibited by L-NAME by 56% and increased by L-arginine by 81%. Furthermore, L-arginine given in combination with L-NAME completely reversed the inhibition of Etx-induced edema produced by L-NAME. These results support the hypothesis that in the late phase NO production is associated with the edema evoked by Etx.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Biochemical computing is an emerging field of unconventional computing that attempts to process information with biomolecules and biological objects using digital logic. In this work we survey filtering in general, in biochemical computing, and summarize the experimental realization of an and logic gate with sigmoid response in one of the inputs. The logic gate is realized with electrode-immobilized glucose-6-phosphate dehydrogenase enzyme that catalyzes a reaction corresponding to the Boolean and functions. A kinetic model is also developed and used to evaluate the extent to which the performance of the experimentally realized logic gate is close to optimal.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Spams and Phishing Scams are some of the abuse forms on the Internet that have grown up now. These abuses influence in user's routine of electronic mail and in the infrastructure of Internet communication. So, this paper proposes a new model messages filter based in Euclidian distance, beyond show the containment's methodologies currently more used. A new model messages filter, based in frequency's distribution of character present in your content and in signature generation is described. An architecture to combat Phishing Scam and spam is proposed in order to contribute to the containment of attempted fraud by mail.
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Three-Phase Induction Motors (TIM) and Arc Welding Machines (AWM) are loads of special behavior widely used in industrial and commercial installations, and therefore may contribute significantly to the deterioration of the quality of energy supplied by utilities. This paper proposes a modeling in constant power of the unbalanced TIM starting using Genetic Algorithm (GA) and AWM short-circuit based on their statics characteristics curves. The proposed models are compared with the conventional models in the literature. The results showed the good performance of the proposed models, allowing a more precise analysis of the real requests of these loads.
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This article aims to demonstrate through performance tests, that it is possible to reuse outdated machines as effective and productive terminals, with the use of LTSP - Linux Terminal Service Project. Additionally, we will demonstrate that companies and institutions concerned with the environment may find this alternative a measure of computational saving and recycling.
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This paper made an analysis of some numerical integration methods that can be used in electromagnetic transient simulations. Among the existing methods, we analyzed the trapezoidal integration method (or Heun formula), Simpson's Rule and Runge-Kutta. These methods were used in simulations of electromagnetic transients in power systems, resulting from switching operations and maneuvers that occur in transmission lines. Analyzed the characteristics such as accuracy, computation time and robustness of the methods of integration.
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Objective. To investigate the long-term outcome and prognostic factors of juvenile dermatomyositis (DM) through a multinational, multicenter study.Methods. Patients consisted of inception cohorts seen between 1980 and 2004 in 27 centers in Europe and Latin America. Predictor variables were sex, continent, ethnicity, onset year, onset age, onset type, onset manifestations, course type, disease duration, and active disease duration. Outcomes were muscle strength/endurance, continued disease activity, cumulative damage, muscle damage, cutaneous damage, calcinosis, lipodystrophy, physical function, and health-related quality of life (HRQOL).Results. A total of 490 patients with a mean disease duration of 7.7 years were included. At the cross-sectional visit, 41.2-52.8% of patients, depending on the instrument used, had reduced muscle strength/endurance, but less than 10% had severe impairment. Persistently active disease was recorded in 41.2-60.5% of the patients, depending on the activity measure used. Sixty-nine percent of the patients had cumulative damage. The frequency of calcinosis and lipodystrophy was 23.6% and 9.7%, respectively. A total of 40.7% of the patients had decreased functional ability, but only 6.5% had major impairment. Only a small fraction had decreased HRQOL. A chronic course, either polycyclic or continuous, consistently predicted a poorer outcome. Mortality rate was 3.1%.Conclusion. This study confirms the marked improvement in functional outcome of juvenile DM when compared with earlier literature. However, many patients had continued disease activity and cumulative damage at followup. A chronic course was the strongest predictor of poor prognosis. These findings highlight the need for treatment strategies that enable a better control of disease activity over time and the reduction of nonreversible damage.
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This note deals whith the problem of extrema which may occur in the step-response of a stable linear system with real zeros and poles. Some simple sufficients conditions and necessary conditions are presented for analyses when zeros located between the dominant and fastest pole does not cause extrema in the step-response. These conditions require knowledge of the pole-zero configuration of the corresponding transfer-function.
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In this paper, it is presented a methodology for three-phase distribution transformer modeling, considering several types of transformer configuration, to be used in algorithms of power flow in three-phase radial distribution networks. The paper provides a detailed discussion about the models and the results from an implementation of the power flow algorithm. The results, taken from three different networks, are presented for several transformer configurations and for voltage regulators as well.
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Indices that report how much a contingency is stable or unstable in an electrical power system have been the object of several studies in the last decades. In some approaches, indices are obtained from time-domain simulation; others explore the calculation of the stability margin from the so-called direct methods, or even by neural networks.The goal is always to obtain a fast and reliable way of analysing large disturbance that might occur on the power systems. A fast classification in stable and unstable, as a function of transient stability is crucial for a dynamic security analysis. All good propositions as how to analyse contingencies must present some important features: classification of contingencies; precision and reliability; and efficiency computation. Indices obtained from time-domain simulations have been used to classify the contingencies as stable or unstable. These indices are based on the concepts of coherence, transient energy conversion between kinetic energy and potential energy, and three dot products of state variable. The classification of the contingencies using the indices individually is not reliable, since the performance of these indices varies with each simulated condition. However, collapsing these indices into a single one can improve the analysis significantly. In this paper, it is presented the results of an approach to filter the contingencies, by a simple classification of them into stable, unstable or marginal. This classification is performed from the composite indices obtained from step by step simulation with a time period of the clearing time plus 0.5 second. The contingencies originally classified as stable or unstable do not require this extra simulation. The methodology requires an initial effort to obtain the values of the intervals for classification, and the weights. This is performed once for each power system and can be used in different operating conditions and for different contingencies. No misplaced classification o- - ccurred in any of the tests, i.e., we detected no stable case classified as unstable or otherwise. The methodology is thus well fitted for it allows for a rapid conclusion about the stability of th system, for the majority of the contingencies (Stable or Unstable Cases). The tests, results and discussions are presented using two power systems: (1) the IEEE17 system, composed of 17 generators, 162 buses and 284 transmission lines; and (2) a South Brazilian system configuration, with 10 generators, 45 buses and 71 lines.