912 resultados para HIGH-VOLTAGE AND HIGH-CURRENT


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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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Introduction: The use of psychoactive substances by the student population has been the object of various studies in Brazil. Objective: To determine the prevalence of substance use among students. Methods: Quantitative study with a closed questionnaire based on standardized assessment instruments was developed. It consists of questions related to types of psychoactive substance use, abuse, frequency and duration of use, self-criticism regarding the use, consequences of use in relation to health, and misdemeanors committed under the influence of psychoactive substances. The sample included the participation of 268 students. A total of 183 (68.3%) questionnaires were analyzed, and only those with positive result for substance abuse at some point in life, the remainder, 85 (31%) questionnaires, had negative responses to psychoactive substances. Results: Students’ responses to the two years surveyed indicated that the first psychoactive substance used was alcohol (77.9%), followed by tobacco use (10.9%), and marijuana (7.6%). Of the students surveyed, 145 (79.2%) answered that still make use of psychoactive substances, and the current frequency of use varies from one or more times per week. When asked about the possibility of being or becoming drug addicts, 169 (92.3%) responded that they are not or will not become dependent. Conclusion: The results indicate the high rate of substance use among college students surveyed, and point to their contradiction to consider such psychoactive substances harmful to their health.

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Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

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The nanostructured materials over the last decade have been increasing the variety of studies and research applications in many industries. From the understanding and manipulation of nanoscale is possible to obtain high-performance materials. One method, which has been very effective in obtaining of nanostructured composites, is the electrospinning, a technique that uses electrostatic forces to produce fibers from a polymer solution. By understanding and controlling of process conditions, such as solution viscosity, working distance, the velocity of the collector, applied voltage and others conditions, it is possible to obtain fibers in many different morphologies. This work aims to obtain nanostructured composites from polysulfone (PSU) a thermoplastic polymer with high oxidation resistance and good mechanical strength at high temperatures and carbon nanotubes (CNTs) that are excellent reinforcements for polymer materials, their mechanical resistance is greater than that of all known materials; using the electrospinning process via polymer solution. Were used polysulfone solutions, n,n-ndimetil acetamide (PSU / DMAc) and this same solution added of CNTs in order to obtain the nanofibers. In both cases were analyzed the effectiveness of the process from the analysis of fiber diameters, rheological behavior and infrared spectroscopy. The results obtained confirmed the efficiency of the electrospinning process to obtain polymeric fibers

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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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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Among the various school functions in capitalist society there in the literature and common sense that the school would have a central role in correcting social inequalities produced by the capitalist mode of production. We see, in today's society, children and young people who moved by the desire to get out of where they are, usually on the outskirts, in a vulnerable situation, seek growth through the study; They see it as a way out to another reality with more opportunit ies and chances for improvement, both as regards their quality of life, and even want to change, change and influence their own reality or part of it, with the knowledge learned in school. On the other hand, there are theorists who maintain that the school reproduces the basic features of the social structure and the current system of power in society. Our goal is to discuss the transformative potential of education as opposed to its role of reproduction of social inequalities, through the essential role of the teacher, who has a high profile role when it comes to change. The teacher is one of the first professionals that we remember when we turn to the school and refer to the systematic teaching. But sometimes forms of education present in the school, afflicting much of children and young people and are characterized in order to favor certain classes and eventually stop the growth and development of those who do not meet the required standards. In this paper we intend to compare two lines of thought, alluding to pedagogical activities in class, the Paulo Freire, which brings the teacher's figure with a responsible actor for lead students to reflection of their practice; and Pierre Bourdieu, which considers the pedagogical practice as an act of imposition of values of the ruling class. The work will address the issue from literature

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Light-emitting electrochemical cells (LECs) made of electroluminescent polymers were studied by d.c. and transient current-voltage and luminance-voltage measurements to elucidate the operation mechanisms of this kind of device. The time and external voltage necessary to form electrical double layers (EDLs) at the electrode interfaces could be determined from the results. In the low-and intermediate-voltage ranges (below 1.1 V), the ionic transport and the electronic diffusion dominate the current, being the device operation better described by an electrodynamic model. For higher voltages, electrochemical doping occurs, giving rise to the formation of a p-i-n junction, according to an electrochemical doping model. Copyright (C) EPLA, 2012

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Objective: The aim of the present study was to investigate the FHR parameters in term pregnancies complicated by asthma. Study design: prospective cross-sectional study performed between July 2008 and November 2009. Twenty-one singleton pregnancy between 36 and 40 weeks gestation with diagnosis of maternal asthma and no current use of oral corticosteroids were compared with 30 pregnancies without morbidities at the same gestational age. The computerized cardiotocography (System 8002, Sonicaid) was performed and 30 min analysis was studied. Statistical analysis included Student's t-test or Mann-Whitney U test for comparisons between groups. Categorical data were compared using the chi(2)-test or Fisher's exact test. Results: There were no significant differences in FHR parameters analyzed by computerized cardiotocography: basal FHR (p = 0.80), number of accelerations >10 bpm (p = 0.08) or >15 bpm (p = 0.20), duration of high episodes (p = 0.70), duration of low episodes (p = 0.46) and STV (p = 0.66). Asthmatic mothers presented mean number of fetal movement per hour significantly lower than control group (34.6 +/- 28.2 vs. 60.6 +/- 43.1, p = 0.02). Conclusion: Computerized cardiotocography demonstrates no association between the abnormal parameters of FHR and maternal asthma in term pregnancies. Maternal asthma was associated with less fetal movements per hour, suggesting further studies on the counting of fetal movements in pregnant women with asthma.

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Retinal nerve fiber evaluation is important in the diagnosis and management of several diseases of the anterior visual pathway. In this report we review the clinical findings and the current techonologies avalilable to analyse the retinal nerve fiber layer. We furthermore review the main findings in several disease of the anterior visual pathways including inflammatory, ischemic, toxics, hereditary, compressive and traumatic optic neuropathies as well as lesion of the optic chiasm, optic tract and lateral geniculate body.

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The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10(17) eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shortly after the detection of air showers of special interest, e. g., showers produced by very high-energy cosmic rays or showers with atypical longitudinal profiles. The former events are of particular importance for the determination of the energy scale of the Observatory, and the latter are characteristic of unusual air shower physics or exotic primary particle types. The purpose of targeted (or "rapid") monitoring is to improve the resolution of the atmospheric measurements for such events. In this paper, we report on the implementation of the rapid monitoring program and its current status. The rapid monitoring data have been analyzed and applied to the reconstruction of air showers of high interest, and indicate that the air fluorescence measurements affected by clouds and aerosols are effectively corrected using measurements from the regular atmospheric monitoring program. We find that the rapid monitoring program has potential for supporting dedicated physics analyses beyond the standard event reconstruction.

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Human bocavirus (HBoV) is a human virus associated with respiratory disease in children. Limited information is available on acute infection with HBoV among children admitted to hospital with community-acquired pneumonia in tropical regions and the current diagnosis is inadequate. The aims were to diagnose and describe acute HBoV infections among children hospitalized for community-acquired pneumonia. In Salvador, Brazil, 277 children with community-acquired pneumonia were prospectively enrolled. Paired serum samples were tested by IgG, IgM, and IgG-avidity enzyme immunoassays (EIAs) using recombinant HBoV VP2. HBoV DNA was detected in nasopharyngeal aspirates and serum by a quantitative polymerase-chain reaction (PCR). HBoV DNA was detected in nasopharyngeal aspirates of 62/268 (23%) children and 156/273 (57%) were seropositive. Acute primary HBoV infection was reliably diagnosed (bearing at least two acute markers: Positive IgM, a fourfold increase/conversion of IgG, low IgG avidity or viremia) in 21 (8%) of 273 patients, 90% of 20 had HBoV DNA in nasopharyngeal aspirates, 83% with a high DNA load. The median age of infection with HBoV was 16 months, range 5-36.Community-acquired pneumonia was confirmed radiographically in 85% of 20 patients with acute HBoV infection diagnosed serologically. HBoV DNA was found in nasopharyngeal aspirates of 42/246(17%) children without an acute primary HBoV infection and available nasopharyngeal aspirate. Four children with HBoV secondary immune responses were detected, lacking both IgM and viremia. HBoV infection was diagnosed accurately in children aged 5-36 months with community-acquired pneumonia confirmed radiographically. PCR of nasopharyngeal aspirates is not a reliable marker of acute HBoV infection. J. Med. Virol. 84:253-258, 2012. (C) 2011 Wiley Periodicals, Inc.