19 resultados para sensory

em Repositório Científico do Instituto Politécnico de Lisboa - Portugal


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This study is primarily focused in establishing the solid-state sensory abilities of several luminescent polymeric calix[4]arene-based materials toward selected nitroaromatic compounds (NACs), creating the foundations for their future application as high performance materials for detection of high explosives. The phenylene ethynylene-type polymers possessing bis-calix[4]arene scaffolds in their core were designed to take advantage of the known recognition abilities of calixarene compounds toward neutral guests, particularly in solid-state, therefore providing enhanced sensitivity and selectivity in the sensing of a given analyte. It was found that all the calix[4]arene-poly(para-phenylene ethynylene)s here reported displayed high sensitivities toward the detection of nitrobenzene, 2,4-dinitrotoluene and 2,4,6-trinitrotoluene (TNT). Particularly effective and significant was the response of the films (25-60 nm of thickness) upon exposure to TNT vapor (10 ppb): over 50% of fluorescence quenching was achieved in only 10 s. In contrast, a model polymer lacking the calixarene units showed only reduced quenching activity for the same set of analytes, clearly highlighting the relevance of the macrocyclics in promoting the signaling of the transduction event. The films exhibited high photostability (less than 0.5% loss of fluorescence intensity up to 15 min of continuous irradiation) and the fluorescence quenching sensitivity could be fully recovered after exposure of the quenched films to saturated vapors of hydrazine (the initial fluorescence intensities were usually recovered within 2-5 min of exposure to hydrazine).

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Abstract: Background: Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disease leading to sensory and motor polyneuropathies, and functional limitations. Liver transplantation is the only treatment for FAP, requiring medication that negatively affects bone and muscle metabolism. The aim of this study was to compare body composition, levels of specific strength, level of physical disability risk, and functional capacity of transplanted FAP patients (FAPTx) with a group of healthy individuals (CON). Methods: A group of patients with 48 FAPTx (28 men, 20 women) was compared with 24 CON individuals (14 men, 10 women). Body composition was assessed by dual-energy X-ray absorptiometry, and total skeletal muscle mass (TBSMM) and skeletal muscle index (SMI) were calculated. Handgrip strength was measured for both hands as was isometric strength of quadriceps. Muscle quality (MQ) was ascertained by the ratio of strength to muscle mass. Functional capacity was assessed by the six-minute walk test. Results: Patients with FAPTx had significantly lower functional capacity, weight, body mass index, total fat mass, TBSMM, SMI, lean mass, muscle strength, MQ, and bone mineral density. Conclusion: Patients with FAPTx appear to be at particularly high risk of functional disability, suggesting an important role for an early and appropriately designed rehabilitation program.

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Introduction: Familial amyloidotic polyneuropathy (FAP) is a neurodegenerative disease that leads to sensory and motor polyneuropathies as well as functional limitations. So far, liver transplantation is the only treatment for FAP because the mutated protein causing the disease is mainly produced in the liver. With the increasing survival of transplant recipients, functional and cardiovascular problems as consequences of immunosuppressant side effects are increasing associated with sedentary lifestyles and/or retransplantation status. We sought to analyze the impact of exercise training programs on 1 FAP patient’s course long-term after liver transplantation. Methodology. A FAP patient (female; 49 years of age; body mass index 18.8 kg/m2) underwent a liver transplantation 133 months before assessment. She was assessed for body composition, isometric quadriceps muscle strength, functional capacity, fatigue, and levels of physical activity before and after a 6-month period of combined exercise training. Results: After the exercise training program, almost all variables were improved, namely, total body skeletal muscle mass, proximal femoral bone mineral density, quadriceps strength, maximal oxygen consumption on 6 minutes walk test (6mwt) or VO2peak, total ventilation on 6mwt, and fatigue. The improvement in distance on 6mwt (69.2 m) was clinically significant. Preintervention the levels of physical activity were below international recommendations for health; after the program they achieved the recommendations. Conclusion: The results showed an improvement in functional capacity with a decrease in future disability risk associated with a better lifestyle with respect to physical activity levels in 1 patient.

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Mestrado em Radiações Aplicadas às Tecnologias da Saúde. Área de especialização: Ressonância Magnética

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Liver transplantation is nowadays the only effective answer to adjourn the outcome of functional limitations associated with familial amyloidotic polyneuropathy (FAP), a neurodegenerative disease characterized by sensory and motor polyneuropathies. Nevertheless, there is a detrimental impact associated with the after-surgery period on the fragile physical condition of these patients. Exercise training has been proven to be effective on reconditioning patients after transplantation. However, the effects of exercise training in liver transplanted FAP patients have not been scrutinized yet.

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Estudou-se a relação entre a segurança da vinculação e a qualidade do processamento sensorial na primeira infância. Para o efeito, seleccionou-se uma amostra normativa de 40 díades mãe-bebé, com crianças entre os 11 e os 18 meses. Avaliou-se a qualidade da vinculação, observando a díade no procedimento Situação Estranha. Classificaram-se 17 (42,5%) das crianças no grupo de vinculação segura, sendo que as restantes 23 (57,5%) revelaram uma vinculação não segura. A qualidade do processamento sensorial avaliou-se através do Teste de Funções Sensoriais. Constatou-se que a segurança da vinculação infantil associava-se a um score agregando quatro factores ambientais (nível sócio-económico dos pais; existência de internamentos hospitalares; coeficiente de número de irmãos; local onde a criança passa o dia). O Teste de Funções Sensoriais não apresentou valor prognóstico relativamente ao tipo de vinculação. Porém, a boa qualidade no processamento da informação sensorial parece constituir um factor de resiliência no desenvolvimento da vinculação.

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Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo Automação e Electrónica Industrial

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Agência Financiadora: Fundação para a Ciência e a Tecnologia/MCTES (Portugal) - PEst-OE/EQB/UI0702/2012

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Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção do grau de Mestre em Ensino Especial – ramo de Problemas de Cognição e Multideficiência

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Mestrado em Radiações Aplicadas às Tecnologias da Saúde - Ramo de especialização: Imagem por Ressonância Magnética

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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Informática e Computadores

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Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

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Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

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Introdução e Objetivos – Os campos eletromagnéticos estão presentes naturalmente no Universo. Há alguns anos, os valores referentes a campos eletromagnéticos eram relativamente constantes. Com o desenvolvimento da tecnologia, a exposição a novas fontes de radiação eletromagnética aumentou. Desta forma, é normal que a preocupação pública, principalmente sobre os potenciais riscos para a saúde provenientes dos campos eletromagnéticos, tenha aumentado. O objetivo deste trabalho foi conhecer e analisar a preocupação e a perceção dos indivíduos sobre a radiação eletromagnética, tendo por base que um dos principais fatores para a adoção de medidas de precaução é o modo como o risco é percecionado pelo indivíduo. Metodologia – Trata-se de um estudo do tipo descritivo, de natureza quantitativa. A amostra, composta por 320 indivíduos, é de natureza não probabilística de conveniência. Resultados – Verificou-se que os inquiridos se manifestam “pouco preocupados” relativamente à exposição aos campos eletromagnéticos, desconhecem as fontes emissoras de radiação eletromagnética presentes no seu quotidiano e não tomam precauções relativamente à exposição a campos eletromagnéticos. Conclusões – Os indivíduos mostram imaturidade conscienciosa em relação à problemática da radiação eletromagnética, em parte justificada pela ausência de mecanismos sensoriais que a permitam detetar. A aposta na educação e sensibilização pode garantir um futuro com melhor qualidade de vida. É importante reunir esforços de várias entidades (saúde, meios de comunicação social e educação). A escola, através das crianças e jovens, constitui um meio privilegiado para a transmissão de informação.

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New sensory materials based on p-phenylene ethynylene trimers integrating calix[4]arene receptors (CALIX-PET) and tert-butylphenol (TBP-PET) moieties have been synthesized and their sensitivity and selectivity for the detection of nitroaromatic compounds (NACs) such as nitrobenzene (NB), 2,4-dinitrotoluene (2,4-DNT), 2,4,6-trinitrotoluene (TNT) and picric acid (PA) investigated in fluid phase and solid-state. It was found that both fluorophores displayed high sensitivities toward NACs detection in solution as evaluated by the Stern-Volmer formalism. For all the tested explosives, the ratio of fluorescence intensities (F-0/F) is a linear function of the quencher concentration only after appropriate correction of fluorescence quenching data for inner-filter effects. The quenching efficiencies for CALIX-PET and TBP-PET follow the order PA >> TNT > DNT > NB, which correlate well with the quenchers electron affinities as evaluated from their LUMOs energies thereby suggesting a photoinduced electron transfer as the dominant mechanism of fluorescence quenching. The selectivity of these sensors was checked against exemplar interferents possessing differentiated electronic properties (benzoic acid, 2,4-dichlorophenol and benzoquinone) and reduced quenching activity was detected. The quenching efficiencies and response times of the two fluorophores in the solid-state toward NB, 2,4-DNT and TNT vapors were evaluated through steady-state fluorescence quenching experiments with the materials dispersed in polymeric matrices or as neat films. The most significant fluorescence quenching responses were achieved for drop-casted films of TBP-PET upon exposure to nitroaromatics.