Influence of reconstruction parameters during filtered backprojection and ordered-subset expectation maximization in the measurement of the left-ventricular volumes and function during gated SPECT

A crucial method for investigating patients with coronary artery disease (CAD) is the calculation of the left ventricular ejection fraction (LVEF). It is, consequently, imperative to precisely estimate the value of LVEF--a process that can be done with myocardial perfusion scintigraphy. Therefore, the present study aimed to establish and compare the estimation performance of the quantitative parameters of the reconstruction methods filtered backprojection (FBP) and ordered-subset expectation maximization (OSEM). Methods: A beating-heart phantom with known values of end-diastolic volume, end-systolic volume, and LVEF was used. Quantitative gated SPECT/quantitative perfusion SPECT software was used to obtain these quantitative parameters in a semiautomatic mode. The Butterworth filter was used in FBP, with the cutoff frequencies between 0.2 and 0.8 cycles per pixel combined with the orders of 5, 10, 15, and 20. Sixty-three reconstructions were performed using 2, 4, 6, 8, 10, 12, and 16 OSEM subsets, combined with several iterations: 2, 4, 6, 8, 10, 12, 16, 32, and 64. Results: With FBP, the values of end-diastolic, end-systolic, and the stroke volumes rise as the cutoff frequency increases, whereas the value of LVEF diminishes. This same pattern is verified with the OSEM reconstruction. However, with OSEM there is a more precise estimation of the quantitative parameters, especially with the combinations 2 iterations × 10 subsets and 2 iterations × 12 subsets. Conclusion: The OSEM reconstruction presents better estimations of the quantitative parameters than does FBP. This study recommends the use of 2 iterations with 10 or 12 subsets for OSEM and a cutoff frequency of 0.5 cycles per pixel with the orders 5, 10, or 15 for FBP as the best estimations for the left ventricular volumes and ejection fraction quantification in myocardial perfusion scintigraphy.

Fatores de risco relacionados à perda de produtividade laboral e aumento dos custos ambulatoriais de pacientes atendidos por unidades básicas de saúde

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A implementação do Balanced Scorecard nos trabalhos de auditoria interna e o seu contributo para a estratégia organizacional - caso do sector público: autarquia local

Mestrado em Auditoria

European information users: topics from a comparative analysis within the European Union

Purpose – The aim of this article is to present some results from research undertaken into the information behaviour of European Documentation Centre (EDC) users. It will reflect on the practices of a group of 234 users of 55 EDCs covering 21 Member States of the European Union (EU), used to access European information. Design/methodology/approach – In order to collect the data presented here, five questionnaires were sent to users in all the EDCs in Finland, Ireland, Hungary and Portugal. In the remaining EU countries, five questionnaires were sent to two EDCs chosen at random. The questionnaires were sent by post, following telephone contact with the EDC managers. Findings – Factors determining access to information on the European Union and the frequency of this access are identified. The information providers most commonly used to access European information and the information sources considered the most reliable by respondents will also be analysed. Another area of analysis concerns the factors cited by respondents as facilitating access to information on Europe or, conversely, making it more difficult to access. Parallel to this, the aspects of accessing information on EU that are valued most by users will also be assessed. Research limitations/implications – Questionnaires had to be used, as the intention was to cover a very extensive geographical area. However, in opting for closed questions, it is acknowledged that standard responses have been obtained with no scope for capturing the individual circumstances of each respondent, thus making a qualitative approach difficult. Practical implications – The results provide an overall picture of certain aspects of the information behaviour of EDC users. They may serve as a starting point for planning training sessions designed to develop the skills required to search, access, evaluate and apply European information within an academic context. From a broader perspective, they also constitute factors which the European Commission should take into consideration when formulating its information and communication policy. Originality/value – This is the first piece of academic research into the EDCs and their users, which aimed to cover all Members State of the EU.

Divulgação de indicadores sociais: outra dimensão para informações contabilísticas

Mestrado em Contabilidade

Comportamento alimentar e excesso de peso em profissionais do sector da saúde: estratégias para a promoção de saúde no local de trabalho

Mestrado em Intervenção Sócio-Organizacional na Saúde - Área de especialização: Políticas de Administração e Gestão de Serviços de Saúde.

Volunteering for a lifetime? Volunteers’ intention to stay in Portuguese hospitals

Purpose – The current study aims to study Hospital volunteers’ intention to stay in an organization through understanding motivation, management factors and satisfaction. Design/methodology/approach – A total of 304 Hospital volunteers, mainly women, completed a questionnaire measuring motivations, management factors, satisfaction and intention to stay. In this study structural equation modelling was used. Findings – Results demonstrate that there is a positive relationship between (a) motivation and satisfaction, (b) management factors and satisfaction, (c) satisfaction and intention to stay and (d) motivation and management factors. These results present important outcomes that should be reflected in the way organizations operate. Research limitations/implications – This research was restricted to a health care context and to the opinion of only one stakeholder (volunteers). We assume volunteer intent to stay is a main predictor of retention. However, there are other variables not considered here that might influence intent to stay. Practical implications – This research indicates aspects which are most valued by volunteers and allows NPOs to design and establish appropriate and assertive management policies. Originality/value – The value of this paper is that it looks at understanding what factors influence volunteers’ intention to stay.

Estágio profissional: Câmara Municipal da Trofa

Relatório de Estágio apresentado ao Instituto Superior de Contabilidade e Administração do Porto para a obtenção do Grau de Mestre em Auditoria Orientador: Rodrigo Mário Oliveira Carvalho, Dr. Coorientador: Vicente António Fernandes Seixas, Dr.

Conceções, comportamentos e atitudes sobre Educação Ambiental, de crianças do Pré-Escolar e do 1º Ciclo

Mestrado, Educação Pré-Escolar e Ensino do 1º Ciclo do Ensino Básico, 24 de Junho de 2013, Universidade dos Açores (Relatório de Estágio).

Derivative-free nonlinear optimization filter simplex

The filter method is a technique for solving nonlinear programming problems. The filter algorithm has two phases in each iteration. The first one reduces a measure of infeasibility, while in the second the objective function value is reduced. In real optimization problems, usually the objective function is not differentiable or its derivatives are unknown. In these cases it becomes essential to use optimization methods where the calculation of the derivatives or the verification of their existence is not necessary: direct search methods or derivative-free methods are examples of such techniques. In this work we present a new direct search method, based on simplex methods, for general constrained optimization that combines the features of simplex and filter methods. This method neither computes nor approximates derivatives, penalty constants or Lagrange multipliers.

A Cooperativa enquanto espaço do empreendedorismo social: o caso específico da Cooperativa dos Pedreiros

Dissertação de Mestrado apresentada ao Instituto de Contabilidade e Administração do Porto para a obtenção do grau de Mestre em Empreendedorismo e Internacionalização, sob orientação de Doutora Deolinda Meira e Mestre Anabela Ribeiro.

Modelo de previsão meteorológica baseado em sistemas de inferência difusa

Mestrado em Engenharia Electrotécnica e de Computadores

Avaliação e promoção da qualidade dos cuidados prestados em creche familiar: primeiros resultados de um estudo de investigação/acção

Neste artigo apresentam-se os resultados do projecto de investigação/acção Promoção da qualidade dos cuidados prestados em amas e creche familiar (resposta enquadrada pelo Decreto-Lei n.º158/84). É um estudo exploratório, de carácter longitudinal, que teve como principais objectivos: (1) avaliar a qualidade da resposta creche familiar em duas instituições do Distrito de Lisboa; (2) analisar se variáveis como a idade, nível de escolaridade e tempo de experiência das amas, o rácio TE/ama e a idade das crianças estavam associadas à qualidade de cuidados prestada; (3) sistematizar os passos de um programa de promoção da qualidade baseado numa metodologia de consultoria; e (4) determinar os efeitos do programa de consultoria na promoção da qualidade. Participaram neste projecto 10 amas enquadradas na creche familiar de um centro infantil do Centro Distrital de Segurança Social de Lisboa, 21 amas de centros infantis da Santa Casa da Misericórdia de Lisboa e os Técnicos de Enquadramento responsáveis pelo apoio técnico. A Family Child Care Environment Rating Scale, Revised Edition (FCCERS-R) de Harms, Cryer e Clifford (2007), traduzida pela equipa de investigação, foi o principal instrumento utilizado. A recolha de dados decorreu em três momentos: (1) avaliação inicial; (2) reunião de consultoria; e (3) avaliação final.Os resultados encontrados mostram que a qualidade dos cuidados prestados pelas amas é adequada/mínima, com excepção dos itens relacionados com a interacção ama-criança onde a qualidade é boa, sendo a subescala actividades aquela onde foram encontrados valores mais baixos. Não foram encontradas associações significativas entre a qualidade e o tempo experiência das amas. Relativamente às restantes variáveis – idade das amas, rácio TE/ama e idade das crianças – encontraram-se algumas associações com a qualidade global e em algumas das subescalas da FCCERS-R. Foram encontradas diferenças entre os dados da 1ª e da 2ª observação que parecem poder associar-se ao processo de consultoria implementado.

O tema da "saudade" em Gaspar Frutuoso

Colóquio Internacional "Camões e os seus Contemporâneos", Universidade dos Açores, Ponta Delgada, 18 a 20 de Abril de 2012.

Aplicação de dispositivos analógicos reconfiguráveis

Mestrado em Engenharia Electrotécnica e de Computadores