990 resultados para ELECTRICAL CHARACTERISTICS


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Background: Data on human immunodeficiency virus (HIV) infected patients receiving dialysis in Portugal is scarce. Methods: This nationwide epidemiological survey retrospectively evaluates HIV-infected patients on chronic dialysis in Portugal between 1997 and 2002. Results: Sixty-six patients were evaluated (mean age: 39.1±1.6 years, 47 men, 35 black African). Sixty-two patients started dialysis and 4 patients who were receiving dialysis had HIV seroconversion. Eighty-five percent of patients were treated in Lisbon. The annual incidence of HIV-infected patients on chronic dialysis was 0.5% in 1997 and 0.9% in 2002. Seventy-eight percent of patients were HIV-1 infected , 13% had hepatitis B and 31% hepatitis C. Sexual contact was the mode of transmission of HIV in 53% of cases. Four patients had biopsy-proved HIV-associated nephropathy. Ninety-five percent of patients were on chronic hemodialysis. Fifty percent of patients had acquired immunodeficiency syndrome. At follow-up, 12 patients died. HIV-infected CKD patient survival after starting dialysis was 80% at 3 years. Conclusion: The incidence of HIV-infected patients on chronic dialysis in Portugal has almost doubled. Widespread use of highly active antiretroviral therapy and the increasing number of black Africans from former overseas Portuguese colonies now living in Portugal are possible reasons for this large increase.

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In children, vertical transmission is the main form of HIV infection. Our aim was to determine the prevalence of HIV-1 vertical transmission in mother-infant pairs in a public maternity ward in Presidente Prudente, SP. Additionally; we sought to identify characteristics associated with this form of transmission. The files of 86 HIV-1-infected mothers and their newborns referred to a Public Hospital from March 2002 to March 2007 were analyzed. The HIV-1-RNA viral load of the newborns was determined by bDNA. The HIV-1 vertical-transmission rate was 4.6%. Children that were born in the pre-term period and breastfed were at a higher risk of HIV-1 infection (p = 0.005 and p = 0.017 respectively) than children born at term and not breastfed. Prophylactic therapy with zidovudine after birth for newborns was associated with a lower risk of infection (p = 0.003). The number of newborns weighing < 2,500 g was significantly higher for infected children (p = 0.008) than for non-infected newborns. About 22.9% of mothers did not know the HIV-1 status of their newborns eight months after delivery. The study suggests that it is necessary to increase the identification of HIV-1 infection in pregnant women and their newborns as well as to offer and explain the benefits of ARV prophylaxis.

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Nos últimos anos tem-se assistido à introdução de novos dispositivos de medição da poluição do ar baseados na utilização de sensores de baixo custo. A utilização menos complexa destes sistemas, possibilita a obtenção de dados com elevada resolução temporal e espacial, abrindo novas oportunidades para diferentes metodologias de estudos de monitorização da poluição do ar. Apesar de apresentarem capacidades analíticas distantes dos métodos de referência, a utilização destes sensores tem sido sugerida e incentivada pela União Europeia no âmbito das medições indicativas previstas na Diretiva 2008/50/CE, com uma incerteza expandida máxima de 25%. O trabalho desenvolvido no âmbito da disciplina de Projeto consistiu na escolha, caracterização e utilização em medições reais de um sensor de qualidade do ar, integrado num equipamento protótipo desenvolvido com esse fim, visando obtenção uma estimativa da incerteza de medição associada à utilização deste dispositivo através da aplicação da metodologia de demonstração de equivalência de métodos de medição de qualidade do ar definida pela União Europeia. A pesquisa bibliográfica realizada permitiu constatar que o monóxido de carbono é neste momento o parâmetro de qualidade do ar que permite ser medido de forma mais exata através da utilização de sensores, nomeadamente o sensor eletroquímico da marca Alphasense, modelo COB4, amplamente utilizado em projetos de desenvolvimento neste cotexto de monitorização ambiental. O sensor foi integrado num sistema de medição com o objetivo de poder ser utlizado em condições de autonomia de fornecimento de energia elétrica, aquisição interna dos dados, tendo em consideração ser o mais pequeno possível e de baixo custo. Foi utlizado um sistema baseado na placa Arduino Uno com gravação de dados em cartão de memória SD, baterias e painel solar, permitindo para além do registo das tensões elétricas do sensor, a obtenção dos valores de temperatura, humidade relativa e pressão atmosférica, com um custo global a rondar os 300 euros. Numa primeira fase foram executados um conjunto de testes laboratoriais que permitiram a determinação de várias características de desempenho em dois sensores iguais: tempo de resposta, a equação modelo do sensor, avaliação da repetibilidade, desvio de curto e longo termo, interferência da temperatura e histerese. Os resultados demonstraram um comportamento dos sensores muito linear, com um tempo de resposta inferior a um minuto e com uma equação modelo do sensor dependente da variação da temperatura. A estimativa da incerteza expandida laboratorial ficou, para ambos os sensores, abaixo dos 10%. Após a realização de duas campanhas reais de medição de CO em que os valores foram muito baixos, foi realizada uma campanha de quinze dias num parque de estacionamento subterrâneo que permitiu a obtenção de concentrações suficientemente elevadas e a comparação dos resultados dos sensores com o método de referência em toda a gama de medição (0 a 12 mol.mol-1). Os valores de concentração obtidos pelos dois sensores demonstraram uma excelente correlação com o método de referência (r2≥0,998), obtendo-se resultados para a estimativa da incerteza expandida de campo inferiores aos obtidos para a incerteza laboratorial, cumprindo o objetivo de qualidade de dados definido para as medições indicativas de incerteza expandida máxima de 25%. Os resultados observados durante o trabalho realizado permitiram confirmar o bom desempenho que este tipo de sensor pode ter no âmbito de medições de poluição do ar com um caracter mais indicativo.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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During July and August of 1968, a Health survey was conducted on the Ilha da Conceição, an area of Niterói containing approximately one thousand households. The survey was conducted by students from the Universidade Federal Fluminense and the University of Maryland, and was under the supervision of faculty of the Department of Tropical Medicine at U.F.F. and from the Department of Preventive Medicine at the University of Maryland, Baltimore, Maryland, U.S.A. The survey was focused on a 25 percent random sample of the households on the island. Information was obtained from a responsible adult at each Household for completion of a Health questionnaire. Physical measurements, as well as laboratory study information were obtained from, all children in these households. A number of environmental sanitation problems were identified on the Ilha da Conceição. In addition, the survey indicated that approximately half the children had not been adequately immunized against diphteria, pertussis and typhoid. Preventable communicable diseases were the major cause of reported deaths which had occurred in infants ou Household members. The Health of the population on the Ilha da Conceição could well be enhanced by the development of an intelligence system indicating the immunization status of all children in the area. In addition a Health education program for the residents could well be beneficial for improvement of sanitary conditions on the island, as well as maternity and well baby care.

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As part of the health survey on the Ilha da Conceição, a 25 percent random sample of households was identified and a health guestionnaire completed at 236 households. These households contained 536 children, of whom 239 were under age six. Prenatal care had been obtained by 70 percent of the mothers during the pregnancies of the youngest children and 83 percent of these children had been born in hospital. The use of available health facilities was reported more frequently for the younger children in comparison to the older children. Over 90 percent of the children had been vaccinated against one or more diseases but only 50 to 60 percent of the children had complete vaccination against pertussis, diphtheria and tetanus. Almost two-thirds of the stool specimens from the children revealed evidence of parasites and were most commonly found in children two to three years of age. Low hemoglobin values were found commonly under age three and hemoglobin leveis ábove 12 grams were not commonly found until age six. Compared with a North American standard for height and weight, proportionately more children on the Ilha da Conceição were found below the 25th and 3rd percentiles. These findings suggest that an improved health status for the children on the Ilha da Conceição would result from a household health record maintained at the island clinic including current information on vaccination status of all children, and a health education program focused on expectant mothers and the well baby clinic program.

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Sporothrix schenckii has been studied by light microscopy, and also by transmission and scanning electron microscopy. Characteristics of Ascomycetes have been oibserved at the level of the cell-wall and in the synaptic system of the hyphae. Also the perfect state has been discovered. The four spored asei are formed directly from the mycelium and there is no fructification. Dolichoascus schenckii is the name suggested for this perfect state which constitutes a new genus of the Endomycetaceae.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

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Dissertação para obtenção do Grau de Mestre em Energias Renováveis – Conversão Eléctrica e Utilização Sustentável

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RESUMO: O presente trabalho teve como objetivo avaliar, através de diferentes testes, a qualidade fisiológica de sementes de girassol na safrinha do Distrito Federal. Os testes foram realizados no Laboratório de Sementes da Faculdade de Agronomia e Veterinária ? FAV, da Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, em 2014. Foram realizados testes de germinação padrão em areia e em papel, peso da matéria verde e da matéria seca, envelhecimento acelerado, condutividade elétrica e lixiviados de potássio. Foram encontradas diferenças significativas entre os genótipos para as todas as características avaliadas. Dentre os genótipos avaliados, os híbridos que se destacaram quanto a qualidades fisiológicas desejáveis pelos testes de germinação, condutividade elétrica e lixiviação de potássio foram BRS G42 e SYN 045. Materiais genéticos foram identificados no trabalho para possível exploração em programas de melhoramento. ABSTRACT: This study aims to evaluate, through different tests, the seed physiological quality of sunflower in the second crop in the Brazilian savannah. The tests were carried on in the Seed Laboratory of Veterinary and Agriculture Faculty of University of Brasilia, in 2014. The tests were seedling emergence in sand and paper, green and dry matter weight, accelerated aging, electrical conductivity and potassium leached. Related to the evaluated characteristics, significant differences were found between genotypes. Among them, the hybrids that stood out for the physiologic characteristics through the germination test, electric conductivity and potassium leaching were BRS G42 and SYN 045. Genetic materials were identified in this study for a possible exploration in breeding programs.

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Dissertação para obtenção do Grau de Mestre em Engenharia Mecânica