1000 resultados para 151-908A


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The mineral content (phosphorous (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu)) of eight ready-to-eat baby leaf vegetables was determined. The samples were subjected to microwave-assisted digestion and the minerals were quantified by High-Resolution Continuum Source Atomic Absorption Spectrometry (HR-CS-AAS) with flame and electrothermal atomisation. The methods were optimised and validated producing low LOQs, good repeatability and linearity, and recoveries, ranging from 91% to 110% for the minerals analysed. Phosphorous was determined by a standard colorimetric method. The accuracy of the method was checked by analysing a certified reference material; results were in agreement with the quantified value. The samples had a high content of potassium and calcium, but the principal mineral was iron. The mineral content was stable during storage and baby leaf vegetables could represent a good source of minerals in a balanced diet. A linear discriminant analysis was performed to compare the mineral profile obtained and showed, as expected, that the mineral content was similar between samples from the same family. The Linear Discriminant Analysis was able to discriminate different samples based on their mineral profile.

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Electrochemically-reduced graphene oxide (Er-GO) and cobalt oxides (CoOx) were co-electrodeposited by cyclic voltammetry, from an electrolyte containing graphene oxide and cobalt nitrate, directly onto a stainless steel substrate to produce composite electrodes presenting high charge storage capacity. The electrochemical response of the composite films was optimized by studying the parameters applied during the electrodeposition process, namely the number of cycles, scan rate and ratio between GO/Co(NO3)(2) concentrations in the electrolyte. It is shown that, if the appropriate conditions are selected, it is possible to produced binder-free composite electrodes with improved electrochemical properties using a low-cost, facile and scalable technique. The optimized Er-GO/CoOx developed in this work exhibits a specific capacitance of 608 F g(-1) at a current density of 1 A g(-1) and increased reversibility when compared to single CoOx. (C) 2015 Elsevier B.V. All rights reserved.

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This work intends to evaluate the (mechanical and durability) performance of concrete made with coarse recycled concrete aggregates (CRCA) obtained using two crushing processes: primary crushing (PC) and primary plus secondary crushing (PSC). This analysis intends to select the most efficient production process of recycled aggregates (RA). The RA used here resulted from precast products (P), with strength classes of 20 MPa, 45 MPa and 65 MPa, and from laboratory-made concrete (L) with the same compressive strengths. The evaluation of concrete was made with the following tests: compressive strength; splitting tensile strength; modulus of elasticity; carbona-tion resistance; chloride penetration resistance; capillary water absorption; and water absorption by immersion. These findings contribute to a solid and innovative basis that allows the precasting industry to use without restrictions the waste it generates. © (2015) Trans Tech Publications, Switzerland.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Química e Bioquímica

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The recognition profile of the tissue cysts antigens by IgG antibodies was studied during acute and chronic human toxoplasmic infection. Thus the IgG response against Toxoplasma gondii was investigated by immunoblotting in two patients accidentally infected with the RH strain as well as in group of naturally infected patients at acute and chronic phase. There was an overall coincidence of molecular mass among antigens of tachyzoites and tissue cysts recognized by these sera, however, they appear not to be the same molecules. The response against tissue cysts starts early during acute infection, and the reactivity of antibodies is strong against a wide range of antigens. Six bands (between 82 and 151 kDa) were exclusively recognized by chronic phase sera but only the 132 kDa band was positive in more than 50% of the sera analysed. A mixture of these antigens could be used to discriminate between the two infection phases. The most important antigens recognized by the acute and the chronic phase sera were 4 clusters in the ranges 20-24 kDa, 34-39 kDa, 58-80 kDa and 105-130 kDa as well as two additional antigens of 18 and 29 kDa. Both accidentally infected patients and some of the naturally infected patients showed a weak specific response against tissue cyst antigens.

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Parasitological and immunological diagnoses were part of a study conducted among 151 children, 83 immunocompromised (IC) and 68 non-immunocompromised (non-IC) aged from zero to 12, seen at the University Hospital, Universidade Federal de Uberlândia, State of Minas Gerais, Brazil, from February, 1996, to June, 1998. Three fecal samples from each child were analyzed for the parasitological diagnosis by Baermann-Moraes and Lutz methods. The immunological diagnosis to detect IgG and IgM antibodies was carried out by the indirect immunofluorescence antibody test (IFAT) with cryo-microtome sections of Strongyloides stercoralis and Strongyloides ratti larvae as antigens and by the ELISA test with an alkaline extract of S. ratti as the antigens. Of the 151 children 5 (3.31%) were infected with larvae of S. stercoralis (2 cases IC, 2.41%, and 3 cases non-IC, 4.41%). The IFAT-IgG detected 7 (8.43%) serum samples positive among IC, and 2 (2.94%) cases among non-IC. The ELISA-IgG test detected 10 (12.05%) serum samples positive among IC, and 1 (1.47%) case among non-IC. The IFAT-IgM detected 6 (7.22%) positive cases among IC, and 3 (4.41%) cases among non-IC. ELISA-IgM test detected 10 (12.05%) positive cases among IC, and 3 (4.41%) cases among non-IC. It was concluded that the immunological tests can help in the diagnosis of strongyloidiasis in immunocompromised children.

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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Filosofia Geral

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INTRODUCTION: Transthoracic echocardiography is the method of choice for the diagnosis of cardiac myxomas, but the transesophageal approach provides a better definition of the location and characteristics of the tumor. The authors review their thirteen years' experience on the echocardiographic diagnosis of this pathology. METHODS: From 1994 to 2007, 41 cardiac tumors were diagnosed in our echocardiographic laboratory, of which 27 (65.85%) were cardiac myxomas. The exams and the patients' clinical files were retrospectively reviewed. RESULTS: Of the 27 patients, 22 (81.5%) were female, with a mean age of 62.1 +/- 13.6 years (25-84 years). The predominant clinical features were due to the obstruction caused by the tumor in more than two thirds of the patients, followed by constitutional symptoms in one third and embolic events in 30%. In the lab results, anemia was found in three patients and elevated sedimentation rate and CRP in two. In two patients the myxoma was found by chance. All the cases were of the sporadic type, although we found a prevalence of thyroid disease of 14% (4 patients). All patients underwent urgent surgical resection except one, in whom surgery was refused due to advanced age and comorbidities. The myxomas followed a typical distribution with 24 (88.8%) located in the left atrium, 18 of them attached to the atrial septum (AS) and two to the mitral valve. In one patient, the tumor involved both atria. The other two cases originated in the right atrium at the AS. Embolic phenomena were more frequent in small tumors (p = 0.027) and in those with a villous appearance (p = 0.032). Obstructive manifestations were associated with larger tumors (p = 0.046) and larger left atria (p = 0.048). In our series, there were no deaths during hospitalization or in the follow-up period of 5.2 +/- 3.7 years in 19 patients. There were two recurrences, both patients being successfully reoperated. CONCLUSION: Myxoma is the most common cardiac tumor. Transesophageal echocardiography provides excellent morphologic definition, aiding in diagnosis and follow-up. Most clinical manifestations are obstructive and are associated with larger tumors. Small tumors with a friable appearance have a higher chance of embolization. Surgical resection is usually curative and the long-term prognosis is excellent.

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Na revisão bibliográfica encontramos perdas de céluas endoteliais que vão dos 4 aos 25%. Os vários estudos comparam EEC com e sem OVD, EEC e facoemulsificação, cataratas de diferente "dureza", entre outras variáveis. Também a idade, a ruptura do saco ou a perda de vítreo influenciavam estes resultados. As novas tecnologias para facoemulsificação como a peça de mão Ozil torsional que como o nome indica tem a capacidade de movimento torsional lateral (que desbasta a catarata além do movimento longitudinal da peça de mão convencional que emulsifica) torna os gestos cirúrgicos mais eficazes e seguros, reduzindo o traumatismo endotelial. Os AA fizeram um estudo prospectivo em que distribuíram 40 olhos de forma aleatória em dois grupos: 20 olhos foram operados por faco torsional e as restantes 20 cataratas foram operadas por faco convencional. Neste estudo comparativo entre faco torsional e convencional, o primeiro necessitou de menos ultrasons (0,048 versus 0,083), obteve uma acuidade visual média ligeiramente melhor (0,63 versus 0,54) e menor perda celular endotelial (3% versus 6,9%), no 1º dia de pós-operatório. Como se sabe, são múltiplos os factores que influenciam o resultado cirúrgico: o local e tamanho da incisão, a composição das soluções salinas, os dispositivos visco-elásticos, os produtos potencialmente tóxicos aplicados intra-operatoriamente, o tempo de cirurgia, a dureza da catarata, além das técnicas cirúrgicas e dos aparelhos utilizados.

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As úlceras de perna constituem uma importante patologia causando uma diminuição da qualidade de vida, hospitalizações frequentes e aumento da mortalidade e morbilidade. Têm uma incidência de 1% na população adulta, sendo que esta incidência atinge níveis de 10% nos escalões etários superiores a 70 anos. Cerca de 95% das úlceras são venosas, arteriais, mistas ou diabéticas, sendo as mais frequentes as úlceras venosas (70 a 80%). Com o objectivo de optimizar o tratamento e acompanhamento dos doentes com esta patologia, foi criada em 2002 uma Consulta de Referência Multidisciplinar de Úlcera de Perna, no Hospital dos Capuchos. Simultaneamente foi estabelecido um protocolo de referenciação/ tratamento com os Centros de Saúde da Unidade B da Sub-região de Saúde de Lisboa. Neste protocolo o doente é observado no contexto de uma equipa multidisciplinar. Os autores fizeram um estudo retrospectivo dos doentes observados nesta consulta no período entre 2002 e 1º semestre de 2006. Foram observados e acompanhados 294 novos doentes, tendo 80% idade superior a 60 anos. Em relação à etiologia das úlceras, 51,3% (n=151) eram venosas, 35,4% (n=104) eram diabéticas e 6,8% (n=20) eram arteriais. A área média das úlceras foi 23,9cm2 e o número médio de úlceras foi 1,6. A duração das úlceras tinha em 42,3% dos casos um período superior a 6 meses. Das 199 culturas positivas, 40,2% apresentavam Staphylococcus aureus, sendo 21,2% destes MRSA. Com o protocolo instituído, foi obtida uma taxa de cicatrização de 72,2%. 45,9% dos doentes tiveram uma cicatrização total da úlcera em menos de 2 meses, resultados estes que são muito positivos face às taxas de cicatrização de 6 meses referidas na literatura.

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The nomination of Guimarães to host the 2012 European Capital of Culture (ECC) has put on the agenda of the city the need of measuring the effects that the implementation of this mega event could have in it and in the municipality a whole. The balance of the benefits and costs and an extended community involvement tend to reduce negative impacts and enhance positive ones. This chapter analyzes the involvement of population and local associations in the planning and organization of the 2012 Guimarães European Capital of Culture, using the coverage made during 2011 by local and national press of the mega event. A content analysis of the news published covering the period between January and December 2011 and using three newspapers was conducted. From those, two were local and weekly newspapers and one was a national daily one. Looking to data results, it can be concluded that it was poor the community involvement and, also, the one of the cultural associations in the organizations of the 2012 ECC. A strong negative reaction to the model choose to plan the mega event conducted by official organizers was found, which has cast doubts on the desirable participation of the residents and, consequently, on the success of the mega event, especially in a perspective of a medium and long term effects.

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In this paper, we formulate the electricity retailers’ short-term decision-making problem in a liberalized retail market as a multi-objective optimization model. Retailers with light physical assets, such as generation and storage units in the distribution network, are considered. Following advances in smart grid technologies, electricity retailers are becoming able to employ incentive-based demand response (DR) programs in addition to their physical assets to effectively manage the risks of market price and load variations. In this model, the DR scheduling is performed simultaneously with the dispatch of generation and storage units. The ultimate goal is to find the optimal values of the hourly financial incentives offered to the end-users. The proposed model considers the capacity obligations imposed on retailers by the grid operator. The profit seeking retailer also has the objective to minimize the peak demand to avoid the high capacity charges in form of grid tariffs or penalties. The non-dominated sorting genetic algorithm II (NSGA-II) is used to solve the multi-objective problem. It is a fast and elitist multi-objective evolutionary algorithm. A case study is solved to illustrate the efficient performance of the proposed methodology. Simulation results show the effectiveness of the model for designing the incentive-based DR programs and indicate the efficiency of NSGA-II in solving the retailers’ multi-objective problem.

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Nos doentes com infecção pelo vírus da imunodeficiência humana (VIH) o citomegalovírus torna-se um agente de doença importante quando existe imunossupressão avançada. O seu papel como agente de doença pulmonar neste contexto tem sido amplamente debatido. Nos doentes com pneumocistose, a presença do citomegalovírus no pulmão não parece conferir pior prognóstico, excepto nos que recebem terapêutica adjuvante com corticóides. Os autores apresentam dois casos de doentes com infecção VIH e imunossupressão avançada, admitidos na unidade de cuidados intensivos por insuficiência respiratória. Em ambos houve isolamento de Pneumocystis jirovecii no lavado broncoalveolar. Apesar da terapêutica instituída ambos vieram a falecer. A biópsia pulmonar post mortem mostrou, nos dois casos, a presença de Pneumocystis e inclusões por citomegalovírus. Perante este achado tecem-se algumas considerações sobre o papel do citomegalovírus como agente de pneumonia na SIDA e sobre o seu significado como co-infectante na pneumocistose, sobretudo nos casos de falência terapêutica.

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O consumo de energia de forma irracional acarreta desvantagens a nível económico para o consumidor e problemas ambientais para toda a sociedade, como a escassez de recursos naturais e o aumento da poluição. Neste contexto, a otimização energética na indústria, e em particular no setor das borrachas, é indispensável de forma a utilizar racionalmente a energia e assim contribuir para a viabilidade das empresas. Este trabalho, efetuado na Flexocol - Fábrica de Artefactos de Borracha, Lda., teve como principal objetivo efetuar um levantamento energético à unidade fabril e propor alternativas que permitissem a redução do consumo de energia elétrica. Foi ainda realizado um estudo sobre a possibilidade de substituir o n-hexano, solvente utilizado na limpeza dos moldes, por um solvente mais adequado. O levantamento energético efetuado permitiu identificar o consumo das utilidades existentes na Flexocol. Esta empresa consome gasóleo e energia elétrica, sendo esta última, a forma de energia mais consumida correspondendo a 96%. O consumo global de energia é cerca 151 tep anuais, inferior a 500 tep/ano, ou seja é considerada uma empresa não consumidora intensiva de energia. Com base neste levantamento determinou-se os indicadores de consumo específico de energia e da intensidade carbónica, 2,73 tep/ ton e 1684,5 kg CO2/tep. A análise do consumo de energia elétrica dos diferentes equipamentos permitiu verificar que o setor que mais consome energia elétrica é a Vulcanização com 45,8%, seguido do setor da Mistura e Serralharia com 27,5% e 26,7%, respetivamente. O sistema de iluminação nos vários setores foi também alvo de estudo e permitiu identificar a Vulcanização como o setor com mais consumo e o da Mistura como o que menos consome. O estudo das variáveis anteriormente referidas permitiu apresentar algumas propostas de melhoria. Uma das propostas analisada foi implementação de condensadores no quadro parcial de forma a diminuir a energia reativa. Com esta medida prevê-se uma poupança de 5631 €/ano e um retorno de investimento de 0,045 anos. Foi também analisada relativamente à iluminação a possibilidade de instalação de balastros eletrónicos que conduziria a uma poupança na energia elétrica de cerca 7072 kWh/ano, mas com um retorno de investimento desfavorável. Por último estudou-se o solvente alternativo ao n-hexano. A acetona foi o solvente proposto uma vez que tem as propriedades indicadas para o fim a que se destina.