13 resultados para variance inflation factor
em Instituto Politécnico do Porto, Portugal
Resumo:
A anemia ferropénica e a β-Talassemia menor são as anemias microcíticas mais frequentes na prática laboratorial, sendo o seu diagnóstico de extrema importância clínica. O objectivo deste estudo consistiu na análise do poder discriminatório do MAF na caracterização destas anamias. Foi desenvolvido um estudo caso-controlo, tendo sido analisados os hemogramas de um grupo de 47 indivíduos com anemia ferropénica e 37 com β-talassemia, e de um grupo controlo constituído por 58 indivíduos saudáveis. Na diferenciação dos grupos patológicos, apenas a Hemoglobina, o VGM e o RDW apresentaram diferenças significativas. O MAF não demonstrou poder discriminatório relativamente às anemias microcíticas.
Resumo:
A criação de valor no mercado da saúde enquanto factor diferenciador para a negociação de preços e competitividade em contexto de crise mundial Numa altura em que o sector da saúde é apontado como uma área crítica de custos, torna-se cada vez mais difícil orientar a contratação em saúde baseada em valor para os pacientes, ou seja, pelos resultados obtidos e não pelo volume de cuidados prestados. Pretendeu-se estudar a criação de valor no mercado da saúde enquanto factor diferenciador para a negociação de preços e competitividade em contexto de crise económica. Procedeu-se à comparação dos resultados operacionais de uma empresa enquanto prestadora de serviços de Oxigenoterapia ao domicílio, tendo por base duas estratégias diferentes: redução directa de preços ou manutenção de preços com criação de valor para o cliente. As propostas foram posteriormente apresentadas para avaliação e votação on-line por um grupo 8 gestores hospitalares. A proposta baseada em valor (Nº2) apresenta melhores resultados operacionais (41%) embora apresente maiores custos. No que se refere à votação das propostas e tendo em conta o cenário apresentado, metade dos gestores optaram pela proposta Nº1 (N=4) e outra metade pela proposta Nº2 (N=4). Contudo, a maioria dos gestores (N=7) consideraram a proposta Nº1 a mais competitiva em contexto de competição com mais fornecedores. Conclui-se que numa negociação de contratos de cuidados de saúde, uma proposta baseada em valor, pode garantir a manutenção dos preços. Todavia, mantendo-se uma situação económica de recessão e num cenário competitivo de vários fornecedores este tipo de propostas pode não eleita, pelo facto de aparentemente não representar ganhos imediatos para a instituição contratante.
Resumo:
O objectivo da Realidade Virtual é simples de entender mas muito difícil de implementar: criar ambientes completamente indiferenciáveis do mundo real com os quais se possa interagir de um modo natural. Desde a criação do Sensorama por Morton Heiling em 1962, passando pela difusão do conceito pelo público geral na década de 90 até os dias de hoje, a evolução da Realidade Virtual tem sido constante. Este conjunto de tecnologias tem estado envolvido por uma certa descrença por parte da sociedade, motivada pelas grandes expectativas que lhe foram atribuídas e pelo estado de desenvolvimento do hardware aquando do seu auge. No entanto, actualmente assiste-se a um ressurgimento do seu interesse no público geral com a introdução de imagem estereoscópica no cinema ou o sucesso dos controladores da consola Nintendo Wii. Hoje em dia as suas aplicações são muito variadas: desde o treino de pilotos de avião ao tratamento de fobias, passando pela industria do entretenimento e a visita virtual de locais com interesse histórico ou turístico. O objectivo desta tese de mestrado é explorar uma área que ainda não tem sido muito abrangida pela Realidade Virtual e que cobre também aspectos educacionais e lúdicos de modo a ser um factor de atracção para os estudantes do ensino secundário: a simulação de instrumentos musicais. Para tal foi implementado um sistema capaz de simular instrumentos musicais de percussão (uma bateria) utilizando imagem estereoscópica, som posicional e interfaces com o utilizador realistas. Os resultados obtidos nas sessões de avaliação efectuadas por alunos recentemente ingressados no ensino superior demonstram que o sistema desenvolvido, bem como a inovação em interfaces do utilizador com os dispositivos electrónicos de uma forma geral, constituem um meio efectivo na sua motivação para a escolha de um curso na área da engenharia.
Resumo:
A satisfação do utente na comunicação com profissionais de saúde é um indicador de qualidade dos serviços ou instituições. Na literatura não encontramos instrumentos padronizados e validados, que avaliem a satisfação do utente na comunicação com os profissionais de saúde. O presente estudo tem como objetivo construir e validar um instrumento para avaliar a satisfação do utente na comunicação com os profissionais de saúde. Desenvolvemos este estudo em três ciclos. Um primeiro, revisão da literatura, para identificar dimensões e itens da comunicação interpessoal na saúde. No segundo ciclo, conduzimos um método de Delphi modificado em três rondas, com recurso à plataforma informática de questionários Survey Monkey, no qual participou um painel de 25 peritos; estabelecemos como critério mínimo de retenção para a ronda seguinte os itens que recebessem 70% do consenso por parte do painel. Após as três rondas, obtivemos um instrumento com seis dimensões comunicacionais (comunicação verbal, comunicação não verbal, empatia, respeito, resolução de problemas e material de apoio), vinte e cinco itens específicos, e mais seis dimensões genéricas, que avaliam cada uma das dimensões. No terceiro ciclo avaliamos as características psicométricas, em termos de sensibilidade, validade do construto e fidelidade, numa amostra de 348 participantes. Os resultados mostram que todas as categorias de resposta estavam representadas em todos os itens. Validade do construto- a análise fatorial identificou uma solução de seis componentes que explicam 71% da variância total. Fiabilidade - os valores da correlação item-total variam entre 0,387 e 0,722, existindo uma correlação positiva moderada a forte. O valor de alfa de Cronbach (α=0,928) indica que a consistência interna é excelente. O instrumento construído apresenta boas propriedades psicométricas. Fica assim disponível uma nova ferramenta para auxiliar na gestão e no processo de planeamento necessários ao incremento da qualidade nos serviços e instituições de saúde.
Resumo:
Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remolded, and complex composition of the composite itself, which includes glass fibres, matrix and different types of inorganic fillers. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. There are several methods to recycle GFR thermostable materials: (a) incineration, with partial energy recovery due to the heat generated during organic part combustion; (b) thermal and/or chemical recycling, such as solvolysis, pyrolisis and similar thermal decomposition processes, with glass fibre recovering; and (c) mechanical recycling or size reduction, in which the material is subjected to a milling process in order to obtain a specific grain size that makes the material suitable as reinforcement in new formulations. This last method has important advantages over the previous ones: there is no atmospheric pollution by gas emission, a much simpler equipment is required as compared with ovens necessary for thermal recycling processes, and does not require the use of chemical solvents with subsequent environmental impacts. In this study the effect of incorporation of recycled GFRP waste materials, obtained by means of milling processes, on mechanical behavior of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste materials, with distinct size gradings, were incorporated into polyester polymer mortars as sand aggregates and filler replacements. The effect of GFRP waste treatment with silane coupling agent was also assessed. Design of experiments and data treatment were accomplish by means of factorial design and analysis of variance ANOVA. The use of factorial experiment design, instead of the one factor at-a-time method is efficient at allowing the evaluation of the effects and possible interactions of the different material factors involved. Experimental results were promising toward the recyclability of GFRP waste materials as polymer mortar aggregates, without significant loss of mechanical properties with regard to non-modified polymer mortars.
Resumo:
Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remolded, and complex composition of the composite itself, which includes glass fibres, matrix and different types of inorganic fillers. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. There are several methods to recycle GFR thermostable materials: (a) incineration, with partial energy recovery due to the heat generated during organic part combustion; (b) thermal and/or chemical recycling, such as solvolysis, pyrolisis and similar thermal decomposition processes, with glass fibre recovering; and (c) mechanical recycling or size reduction, in which the material is subjected to a milling process in order to obtain a specific grain size that makes the material suitable as reinforcement in new formulations. This last method has important advantages over the previous ones: there is no atmospheric pollution by gas emission, a much simpler equipment is required as compared with ovens necessary for thermal recycling processes, and does not require the use of chemical solvents with subsequent environmental impacts. In this study the effect of incorporation of recycled GFRP waste materials, obtained by means of milling processes, on mechanical behavior of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste materials, with distinct size gradings, were incorporated into polyester polymer mortars as sand aggregates and filler replacements. The effect of GFRP waste treatment with silane coupling agent was also assessed. Design of experiments and data treatment were accomplish by means of factorial design and analysis of variance ANOVA. The use of factorial experiment design, instead of the one-factor-at-a-time method is efficient at allowing the evaluation of the effects and possible interactions of the different material factors involved. Experimental results were promising toward the recyclability of GFRP waste materials as aggregates and filler replacements for polymer mortar, with significant gain of mechanical properties with regard to non-modified polymer mortars.
Resumo:
In this study, the concentration probability distributions of 82 pharmaceutical compounds detected in the effluents of 179 European wastewater treatment plants were computed and inserted into a multimedia fate model. The comparative ecotoxicological impact of the direct emission of these compounds from wastewater treatment plants on freshwater ecosystems, based on a potentially affected fraction (PAF) of species approach, was assessed to rank compounds based on priority. As many pharmaceuticals are acids or bases, the multimedia fate model accounts for regressions to estimate pH-dependent fate parameters. An uncertainty analysis was performed by means of Monte Carlo analysis, which included the uncertainty of fate and ecotoxicity model input variables, as well as the spatial variability of landscape characteristics on the European continental scale. Several pharmaceutical compounds were identified as being of greatest concern, including 7 analgesics/anti-inflammatories, 3 β-blockers, 3 psychiatric drugs, and 1 each of 6 other therapeutic classes. The fate and impact modelling relied extensively on estimated data, given that most of these compounds have little or no experimental fate or ecotoxicity data available, as well as a limited reported occurrence in effluents. The contribution of estimated model input variables to the variance of freshwater ecotoxicity impact, as well as the lack of experimental abiotic degradation data for most compounds, helped in establishing priorities for further testing. Generally, the effluent concentration and the ecotoxicity effect factor were the model input variables with the most significant effect on the uncertainty of output results.
Resumo:
A relação entre consciência fonológica e consciência morfológica e a contribuição independente de cada uma para a aprendizagem da leitura não reúnem ainda consenso na literatura. Alguns autores argumentam que a consciência morfológica não contribui de forma independente da consciência fonológica para a aprendizagem da leitura. No entanto, outros encontraram dados que indicam que a consciência morfológica tem um papel específi co na progressão da aprendizagem da leitura. Todavia, para além da variedade de tarefas usadas não permitir a comparação de resultados, a ausência de estudos prévios sobre a validade e a fi delidade das mesmas conduz a resultados cuja confi abilidade pode ser posta em causa. Este estudo tem como objetivo apresentar uma análise das qualidades psicométricas da PCM - Prova de Consciência Morfológica. A amostra é constituída por 243 crianças do 2.º (n = 79), 3.º (n = 83) e 4.º (n = 81) anos frequentando escolas públicas, urbanas, do distrito do Porto (norte de Portugal). Os resultados revelaram que a PCM possui uma elevada consistência interna (α = .95). Na análise em componentes principais, foi extraído um único fator, com valor próprio igual a 10.88, que explica 54.42% da variância total dos resultados. Os itens são todos saturados no fator, variando as saturações fatoriais entre um mínimo de .42 e o máximo de .91
Resumo:
The change of paradigm imposed by the Bologna process, in which the student will be responsible for their own learning, and the presence of a new generation of students with higher technological skills, represent a huge challenge for higher education institutions. The use of new Web Social concepts in teaching process, supported by applications commonly called Web 2.0, with which these new students feel at ease, can bring benefits in terms of motivation and the frequency and quality of students' involvement in academic activities. An e-learning platform with web-based applications as a complement can significantly contribute to the development of different skills in higher education students, covering areas which are usually in deficit.
Resumo:
Transthyretin (TTR) protects against A-Beta toxicity by binding the peptide thus inhibiting its aggregation. Previous work showed different TTR mutations interact differently with A-Beta, with increasing affinities correlating with decreasing amyloidogenecity of the TTR mutant; this did not impact on the levels of inhibition of A-Beta aggregation, as assessed by transmission electron microscopy. Our work aimed at probing differences in binding to A-Beta by WT, T119M and L55P TTR using quantitative assays, and at identifying factors affecting this interaction. We addressed the impact of such factors in TTR ability to degrade A-Beta. Using a dot blot approach with the anti-oligomeric antibody A11, we showed that A-Beta formed oligomers transiently, indicating aggregation and fibril formation, whereas in the presence of WT and T119M TTR the oligomers persisted longer, indicative that these variants avoided further aggregation into fibrils. In contrast, L55PTTR was not able to inhibit oligomerization or to prevent evolution to aggregates and fibrils. Furthermore, apoptosis assessment showed WT and T119M TTR were able to protect against A-Beta toxicity. Because the amyloidogenic potential of TTR is inversely correlated with its stability, the use of drugs able to stabilize TTR tetrameric fold could result in increased TTR/ABeta binding. Here we showed that iododiflunisal, 3-dinitrophenol, resveratrol, [2-(3,5-dichlorophenyl)amino] (DCPA) and [4- (3,5-difluorophenyl)] (DFPB) were able to increase TTR binding to A-Beta; however only DCPA and DFPB improved TTR proteolytic activity. Thyroxine, a TTR ligand, did not influence TTR/A-Beta interaction and A-Beta degradation by TTR, whereas RBP, another TTR ligand, not only obstructed the interaction but also inhibited TTR proteolytic activity. Our results showed differences between WT and T119M TTR, and L55PTTR mutant regarding their interaction with A-Beta and prompt the stability of TTR as a key factor in this interaction, which may be relevant in AD pathogenesis and for the design of therapeutic TTR-based therapies.
Resumo:
The objectives of this study were to compare how different frailty measures (Frailty Phenotype/FP, Groningen Frailty Indicator/GFI and Tilburg Frailty Indicator/TFI) predict short-term adverse outcomes. Secondarily, adopting a multidimensional approach to frailty (integral conceptual model–TFI), this study aims to compare how physical, psychological and social frailty predict the outcomes. A longitudinal study was carried out with 95 community-dwelling elderly. Participants were assessed at baseline for frailty, determinants of frailty, and adverse outcomes (healthcare utilization, quality of life, disability in basic and instrumental activities of daily living/ADL and IADL). Ten months later the outcomes were assessed again. Frailty was associated with specific healthcare utilization indicators: the FP with a greater utilization of informal care; GFI with an increased contact with healthcare professionals; and TFI with a higher amount of contacts with a general practitioner. After controlling for the effect of life-course determinants, comorbidity and adverse outcome at baseline, GFI predicted IADL disability and TFI predicted quality of life. The effect of the FP on the outcomes was not significant, when compared with the other measures. However, when comparing TFI’s domains, the physical domain was the most significant predictor of the outcomes, even explaining part of the variance of ADL disability. Frailty at baseline was associated with adverse outcomes at follow-up. However, the relationship of each frailty measure (FP, GFI and TFI) with the outcomes was different. In spite of the role of psychological frailty, TFI’s physical domain was the determinant factor for predicting disability and most of the quality of life.
Resumo:
The pathophysiology of depression is related to neurobiological changes that occur in the monoamine system, hypothalamic-pituitary-adrenal axis, neurogenesis system and the neuroimmune system. In recent years, there has been a growing interest in the research of the effects of exercise on brain function, with a special focus on its effects on brainderived neurotrophic factor (BDNF), cortisol and other biomarkers. Thus, the aim of this study is to present a review investigating the acute and chronic effects of aerobic exercise on BDNF and cortisol levels in individuals with depression. It was not possible to establish an interaction between aerobic exercise and concentration of BDNF and cortisol, which may actually be the result of the divergence of methods, such as type of exercises, duration of the sessions, and prescribed intensity and frequency of sessions.