973 resultados para First-principles calculation


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E. faecium was the first reported VRE species, carrying the vanA gene in Brazil. In spite of this, vancomycin-resistant E. faecalis has become the predominant species in Brazilian hospitals. The aim of this study was to evaluate the genetic relatedness of VREs isolated in a Brazilian teaching hospital eight years apart from its first isolation. We analyzed 38 VRE strains obtained from 81 surveillance cultures of patients admitted to the four largest intensive care units in Hospital São Paulo in February, 2006. Presence of the vanA gene was assayed by PCR and PFGE analysis was used for molecular characterization. All VRE strains carried the vanA gene. Two distinct clonal groups were observed among vancomycin-resistant E. faecalis. Vancomycin-resistant E. faecium belonged to five distinct clones were demonstrated by molecular typing. All of these clones were different from the first vancomycin-resistant enterococci clone isolated eight years ago in our hospital.

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Background: Although changes in eating patterns may occur during gestation, predictors of these changes have not been explored. This study aimed to identify predictors of adherence to the Mediterranean diet (MD) from the first to second trimester of pregnancy. Methods: A prospective study was conducted with 102 pregnant women aged 18-40, from the city of Porto, Portugal. Socio-demographic and lifestyle characteristics were assessed through a questionnaire. Food consumption was assessed with a three-day food diary completed during the first and second trimesters. Participants were categorized according to their change in adherence to the MD into the negative change group (i.e., women who had low adherence in each trimester or had high adherence in the first trimester and then low adherence in the second) and the positive change group (i.e., women who had high adherence in both trimesters or had low adherence in the first trimester and then high adherence in the second). Conditional stepwise logistic regression models were performed to assess the potential predictors of negative MD change. Results: Among the 102 women, 39.2% had negative change from the first to the second trimester. The logistic model´s results show that being married (OR=0.26, 95%CI: 0.10, 0.76) and having a higher intake of vegetables in the first trimester (OR=0.17, 95%CI: 0.10, 0.43) were associated with lower odds of having a negative change in adherence to the MD from the first to second trimester. Conclusion: Marital status and vegetable consumption seem to be associated with a lower occurrence of negative change in adherence to the MD from early to middle pregnancy.

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Part of the optical clearing study in biological tissues concerns the determination of the diffusion characteristics of water and optical clearing agents in the subject tissue. Such information is sufficient to characterize the time dependence of the optical clearing mechanisms—tissue dehydration and refractive index (RI) matching. We have used a simple method based on collimated optical transmittance measurements made from muscle samples under treatment with aqueous solutions containing different concentrations of ethylene glycol (EG), to determine the diffusion time values of water and EG in skeletal muscle. By representing the estimated mean diffusion time values from each treatment as a function of agent concentration in solution, we could identify the real diffusion times for water and agent. These values allowed for the calculation of the correspondent diffusion coefficients for those fluids. With these results, we have demonstrated that the dehydration mechanism is the one that dominates optical clearing in the first minute of treatment, while the RI matching takes over the optical clearing operations after that and remains for a longer time of treatment up to about 10 min, as we could see for EG and thin tissue samples of 0.5 mm.

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Com a melhoria das condições de vida verificada nas últimas décadas em Portugal e no mundo, tem-se assistido a um importante desenvolvimento dos atributos funcionais dos edifícios, onde o conforto térmico assume um papel importante, é nesse sentido que a presente dissertação aborda a área do Desempenho Térmico de Edifícios, mais precisamente os do sector residencial. Esta dissertação dividiu-se em três grandes partes: inicialmente é feito um enquadramento teórico do tema, em seguida faz-se a apresentação das metodologias de cálculo e, por último, a apresentação do caso de estudo e análise dos resultados. Procura-se analisar a situação energética no sector residencial, dando particular ênfase às causas e medidas correctivas a aplicar para evitar o aumento do consumo de energia. Também são abordadas as metodologias presentes na Legislação Portuguesa em vigor, e nas novas propostas que espera-se que entrem em vigor a 1 de Dezembro de 2013. Sendo que o principal objectivo desta dissertação é o estudo da nova proposta legislativa e apresentar um documento que procure efectuar uma comparação detalhada entre o DL 80/2006, de 4 de Abril e o DL 118/20013, de 20 de Agosto e sobretudo referir quais as implicações ao nível das soluções construtivas adoptadas e da certificação energética. Após esta analise, é apresentado um caso de estudo que consiste num edifício de habitação unifamiliar que será alvo da aplicação destes dois documentos. Por último é apresentada uma análise dos resultados comparando a classe energética conseguida pelo edifício através das duas metodologias de cálculo.

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Sabendo que as energias de origem fóssil não são inesgotáveis e que afetam a qualidade do ambiente, nos últimos anos, o interesse pelas energias renováveis mereceu a atenção de ambientalistas e de governantes. Para diminuir a importação de energia, o próprio governo de Portugal incentivou, através de medidas legislativas diversas, a instalação de sistemas alternativos de produção elétrica. Face à pertinência desta matéria, a dissertação, Viabilidade Técnica e Económica das Diferentes Tecnologias de Microprodução, aborda o aproveitamento de energias renováveis através de tecnologias de Microprodução ligadas à rede elétrica. Nesta dissertação, numa primeira fase, apresentam-se os sistemas de microprodução existentes no mercado, descrevem-se os componentes que os constituem e destacam-se os aspetos legislativos aplicáveis. Numa segunda fase, com o objetivo de suportar a elaboração de uma ferramenta informática para apoio na escolha de equipamentos de microprodução, procede-se à análise financeira de tecnologias de microprodução, indicando os modelos matemáticos necessários. Um dos objetivos da dissertação, consiste na construção de uma ferramenta informática de cálculo e na sua aplicação a dois estudos de caso. Esse programa informático foi elaborado em Excel e é capaz de fornecer uma estimativa da produção de energia anual e da avaliação da viabilidade técnico-económica de cada tecnologia e pretende apoiar a decisão do investidor em tecnologias de microprodução. Tendo sido realizados dois estudos de caso - um edifício habitacional unifamiliar e um edifício Industrial – foi possível verificar o funcionamento da aplicação e a sua utilidade na determinação da solução mais vantajosa na escolha de uma tecnologia de microprodução, uma vez que, introduzidos os dados adequados, são gerados os cálculos que permitem fornecer uma visão de conjunto, possibilitando a comparação das diferentes propostas.

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A case of meningitis due to Staphylococcus warneri in a patient with a hyperinfection with Strongyloides stercoralis possibly associated with rituximab treatment for mantel cell lymphoma is reported for the first time in the literature. The patient was a 59-year-old woman, with a 3-year history of an apparently well controlled lymphoma after treatment with chemotherapy-immunotherapy and then immunotherapy alone, and diagnosis of strongyloidiasis. Meningitis was diagnosed by cerebrospinal fluid culture and tested with an automated plate system. The patient was successfully treated with vancomycin; although fever and productive cough persisted. Severe gastrointestinal symptoms and pneumonia developed three weeks later. Hyperinfection syndrome by S. stercoralis was diagnosed, with abundant larvae in feces and expectoration.

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Disseminated histoplasmosis is a relatively common AIDS-defining illness, occurring in almost 4% of patients living in endemic areas and it may be the first clinical expression of the HIV infection. A broad spectrum of clinical skin lesions associated with Histoplasma capsulatum infection have been described in AIDS patients, such as erythematous macules, papules, nodules, and pustules. Herpetic, acneiform, erythema multiforme-like, molluscum contagiosum-like, vasculitic, and exfoliative forms have also been reported. To our knowledge, this is the first case of disseminated histoplasmosis in an AIDS patient presented as a rupioid eruption.

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Este relatório de estágio, inserido no âmbito da unidade curricular de Integração Curricular: Prática Educativa e Relatório de Estágio, apresenta-se neste momento como o culminar de um processo académico que se iniciou num primeiro ciclo de estudos, na Licenciatura em Educação Básica, e se complementou com o segundo ciclo de estudos, o Mestrado em Ensino do 1.º e 2.º Ciclo do Ensino Básico. Pretende-se com este documento analisar reflexivamente o percurso de desenvolvimento profissional da mestranda, no âmbito da sua intervenção educativa em contexto do 1.º e 2.º CEB. Evidencia-se, num primeiro momento, o quadro referencial académico e profissional que sustenta e norteia a intencionalidade educativa inerente a toda a ação pedagógica da professora estagiária. Destaca-se, a nível académico, os pressupostos legais que orientam a formação profissional dos docentes e a prática educativa supervisionada. Salienta-se, a nível profissional, alguns princípios teóricos e práticos que guiam o professor para a sua ação, dando especial destaque à importância da reflexão, da investigação e da supervisão nos diferentes momentos da ação pedagógica. O segundo momento é dedicado à descrição das experiências educativas vivenciadas nos contextos educativos do 1.º e 2.º CEB, em cooperação com o par pedagógico. Procede-se, primeiramente, à descrição dos contextos educativos com objetivo de contextualizar as práticas educativas propostas e realizadas pela professora estagiária. A análise crítica e fundamentada acontece seguidamente e recai sobre a intervenção educativa dentro da sala de aula e a dinamização de projetos educativos contextualizados não só para as turmas, como para a escola e para toda a comunidade educativa. A realização deste documento conclui um momento da formação inicial de professores, mas fica a certeza de que a construção de aprendizagens não termina aqui, sendo este apenas o início de um longo caminho envolvido por um conjunto de desafios que culminarão sempre em aprendizagens.

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Dissertação para obtenção do Grau de Doutor em Engenharia Biomédica

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An autochthonous case of visceral leishmaniasis is reported in a dog (Canis familiaris) as an apparently natural infection in a non-endemic area. DNA obtained from spleen and liver samples produced the expected fragment in a Leishmania-specific rDNA-based nested-PCR assay. The PCR product, a 490 bp fragment, was sequenced and the nucleotide sequence was identical to that of Leishmania (Leishmania) infantum chagasi. These results are surprising since no autochthonous human or canine cases of visceral leishmaniasis have ever been reported in this municipality. This case suggests that natural transmission of this disease is occurring in this area.

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We report a case of a woman, aged 53 years, presenting with a right atrial mass due to idiopathic fibrosing mediastinitis with periaortic involvement. This challenging diagnosis was confirmed by different imaging modalities and histopathologic analysis. The diagnosis of cardiac tumours is often difficult. To our knowledge, this is the first reported case of an intracavitary cardiac mass due to fibrosing mediastinitis. This rare disorder, which is characterized by invasive proliferation of fibrous tissue within the mediastinum, should be included in the differential diagnosis of intracardiac tumours.

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We report the first isolation of Dengue virus 4 (DENV-4) in the state of São Paulo, from two patients - one living in São José do Rio Preto and the other one in Paulo de Faria, both cities located in the Northwest region of the state. The virus isolations were accomplished in the clone C6/36 Aedes albopictus cell line, followed by indirect immunofluorescence assays, performed with type-specific monoclonal antibodies that showed positive reactions for DENV-4. The results were confirmed by Nested RT-PCR and Real-Time RT-PCR assays. The introduction of DENV-4 in a country that already has to deal with the transmission of three other serotypes increases the possibility of the occurrence of more severe cases of the disease. The importance of early detection of dengue cases, before the virus spreads and major outbreaks occur, should be emphasized.

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The seroprevalence and geographic distribution of HTLV-1/2 among blood donors are extremely important to transfusion services. We evaluated the seroprevalence of HTLV-1/2 infection among first-time blood donor candidates in Ribeirão Preto city and region. From January 2000 to December 2010, 1,038,489 blood donations were obtained and 301,470 were first-time blood donations. All samples were screened with serological tests for HTLV-1/2 using enzyme immunoassay (EIA). In addition, the frequency of coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), Chagas disease (CD) and syphilis was also determined. In-house PCR was used as confirmatory test for HTLV-1/2. A total of 296 (0.1%) first-time donors were serologically reactive for HTLV-1/2. Confirmatory PCR of 63 samples showed that 28 were HTLV-1 positive, 13 HTLV-2 positive, 19 negative and three indeterminate. Regarding HTLV coinfection rates, the most prevalent was with HBV (51.3%) and HCV (35.9%), but coinfection with HIV, CD and syphilis was also detected. The real number of HTLV-infected individual and coinfection rate in the population is underestimated and epidemiological studies like ours are very informative.

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Infrapopliteal mycotic aneurysm resulting from endocarditis is rare, with only a few reported cases. We describe the case of a 28-year-old male patient who was suffering with pain and edema in the right leg. The ultrasound revealed an aneurysm of the right tibioperoneal trunk and a deep vein thrombosis (DVT). The patient was admitted and developed acute congestive heart failure, being diagnosed with possible endocarditis. A pseudo-aneurysm was revealed by arteriography. Aggressive antibiotic treatment was initiated, and open surgery confirmed a mycotic pseudo-aneurysm of the tibioperoneal trunk. To our knowledge, this is the 8th case reported of an infected aneurysm in this particular location.