23 resultados para Interfacing circuits
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This paper presents some methodologies for reactive energy measurement, considering three modern power theories that are suitable for three-phase four-wire non-sinusoidal and unbalanced circuits. The theories were applied in some profiles collected in electrical distribution systems which have real characteristics for voltages and currents measured by commercial reactive energy meters. The experimental results are presented in order to analyze the accuracy of the methodologies, considering the standard IEEE 1459-2010 as a reference. Finally, for additional comparisons, the theories will be confronted with the modern Yokogawa WT3000 energy meter and three samples of a commercial energy meter through an experimental setup. © 2011 IEEE.
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Pós-graduação em Engenharia Elétrica - FEIS
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Foram investigados a prevalência e os fatores de risco da leptospirose bovina no Estado do Maranhão. O Estado foi dividido em quatro circuitos amostrais com base em parâmetros de produção distintos que variam conforme os diferentes sistemas de produção, as práticas de manejo, a finalidade de exploração, o tamanho médio dos rebanhos e os sistemas de comercialização. Objetivou-se estudar as características epidemiológicas da leptospirose bovina no Estado do Maranhão, de modo a determinar a prevalência em bovinos e em rebanhos, detectar as sorovariedades de Leptospira spp. presentes, identificar os fatores de risco eventualmente associados à leptospirose em bovinos e diferenciar os circuitos pecuários entre si no que se refere à prevalência de leptospirose. A pesquisa foi realizada em 136 propriedades rurais pertencentes ao circuito I, no qual 841 fêmeas bovinas com idade igual ou superior a 24 meses foram analisadas; 238 do circuito II, com 2.582 fêmeas analisadas; 122 do circuito III, com 869 fêmeas analisadas; e 77 do circuito IV, com 540 fêmeas analisadas; no total, 573 propriedades e 4.832 fêmeas foram estudadas. A presença de anticorpos contra Leptospira spp. foi verificada pela técnica de soroaglutinação microscópica (SAM). Das 4.832 fêmeas bovinas analisadas, 1.904 (35,94%; IC 95% = 33,01% - 38,98%) foram reagentes. Das 573 propriedades analisadas, 380 (64,81%; IC 95% = 61,10% - 68,35%) foram consideradas positivas. As sorovariedades Hardjo e Wolffi foram as mais frequentes em todo o Estado. O circuito III foi o que apresentou menor prevalência de leptospirose em todas as comparações. As variáveis identificadas como fatores de risco de leptospirose foram: presença de equinos (p = 0,000), presença de capivaras (p = 0,034) e rebanhos bovinos com 32 ou mais fêmeas adultas (p = 0,002).
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Objective. To evaluate the neuropsychological profile and health-related quality of life (HRQOL) of adults who had rheumatic fever (RF) during childhood with and without Sydenham's chorea (SC).Methods. Three groups of patients were assessed: adults who had RF with SC during childhood (SC group), adults who had RF without SC during childhood (RF group), and controls (CT group). A range of neuropsychological tests looked at several cognitive domains. HRQOL was measured through a Brazilian version of the Short Form 36 (SF-36) health survey.Results. Twenty patients were included in the SC group, 23 patients in the RF group, and 19 patients in the CT group. The 3 groups were homogeneous regarding sex (P = 0.078), age (P = 0.799), schooling (P = 0.600), socioeconomic status (P = 0.138), intelligence quotient (P = 0.329), and scores for anxiety (P = 0.156) and depression (P = 0.076). The SC group demonstrated inferior performance in tests that assessed attention (Digit Span Forward [ P = 0.005], Corsi Block Forward [ P = 0.014]), speeded information processing (Trail Making A [ P = 0.009], Symbol Search [ P = 0.042]), and executive functions and working memory (Corsi Block Backward [ P = 0.028]), and higher scores for attention deficit scale (P = 0.030) when compared with the RF and CT groups. They also showed a tendency toward lower scores in the physical aspects, vitality, emotional aspects, and mental health domains of the SF-36. The RF group had a lower score for the general health domain than the CT group (P = 0.030).Conclusion. Patients who had SC during childhood can exhibit inferior performance in tasks that evaluate attention, speeded information processing, executive functions, and working memory in adult life. Therefore, there is indirect evidence of the persistence of dysfunction in cerebral circuits involved with the basal ganglia. They also presented a worse self-evaluation in HRQOL that was not related to cognitive impairments.
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OBJETIVO: Analisar o efeito de 12 semanas de intervenção envolvendo prática de atividade física, orientações alimentar e psicológica sobre fatores de risco para o desenvolvimento da síndrome metabólica em crianças e adolescentes obesos. MÉTODOS: Estudo longitudinal com 23 crianças e adolescentes obesos, com idade entre seis e 16 anos (12,0±3,2 anos). Foram mensurados: gordura corporal total e de tronco, glicemia, colesterol total e triglicérides, pressão arterial sistólica e diastólica. Os jovens foram submetidos a três sessões semanais de 60 minutos de exercício físico (atividades esportivas recreativas, ginástica, circuitos e caminhadas), durante 12 semanas. O teste do qui-quadrado foi usado para comparar dados categóricos daqueles que apresentaram valores acima das recomendações para cada fator de risco. O teste t para dados pareados foi aplicado para comparar os dois momentos do estudo. RESULTADOS: em indivíduos com alterações metabólicas no início do estudo, observou-se, após a intervenção, a diminuição de 11,6% na glicemia (105 para 93mg/dL; p=0,046) e de 24,9% no triglicérides (217 para 163mg/dL; p=0,013); porém, não houve diferenças na pressão arterial e no colesterol total. CONCLUSÕES: O programa de exercício físico aplicado nas crianças e adolescentes foi eficiente para melhorar os valores de glicemia e triglicérides.
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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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In socio-environmental scenario increased the nature resources concern beyond products and subproducts reuse. Recycling is the approach for a material or energy reintroducing in productive system. This method allows the reduction of garbage volume dumped in environment, saving energy and decreasing the requirement of natural resources use. In general, the ending of expanded polystyrene is deposited sanitary landfills or garbage dumps without control that take large volume and spreads easily by aeolian action, with consequently environmental pollution, however, the recycling avoids their misuse and the obtainment from petroleum is reduced. This work recycled expanded polystyrene via merger and/or dissolution by solvents for the production of integrated circuits boards. The obtained material was characterized in flexural mode according to ASTM D 790 and results were compared with phenolite, traditionally used. Specimens fractures were observed by electronic microscopy scanning in order to establish patterns. Expanded Polyestirene recycled as well as phenolite were also thermo analyzed by TGA and DSC. The method using dissolution produced very brittle materials. The method using merger showed no voids formation nor increased the brittleness of the material. The recycled polystyrene presented a strength value significantly lower than that for the phenolite. (C) 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of ICM11