Optimism on quality of life in Portuguese chronic patients: moderator/mediator?

OBJECTIVE: optimism is an important variable that has consistently been shown to affect adjustment to quality of life in chronic diseases. This study aims to clarify if dispositional optimism exerts a moderating or a mediating influence on the personality traits-quality of life association, in Portuguese chronic patients. METHODS: multiple regression models were used to test the moderation and mediation effects of dispositional optimism in quality of life. A sample of 729 patients was recruited in Portugal's main hospitals and completed self-reported questionnaires assessing socio-demographic and clinical variables, personality, dispositional optimism, quality of life (QoL) and subjective well-being (SWB). RESULTS: the results of the regression models showed that dispositional optimism did not moderate the relationships between personality traits and quality of life. After controlling for gender, age, education level and severity of disease perception, the effects of personality traits on QoL and in SWB were mediated by dispositional optimism (partially and completely), except for the links between neuroticism/openness to experience and physical health. CONCLUSION: dispositional optimism is more likely to play a mediating, rather than a moderating role in personality traits-quality of life pathway in Portuguese chronic patients, suggesting that "the expectation that good things will happen" contributes to a better quality of life and subjective well-being

Psychosocial factors as predictors of quality of life in chronic Portuguese patients

BACKGROUND: Chronic illnesses are diseases of long duration and generally of slow progression. They cause significant quality of life impairment. The aim of this study was to analyse psychosocial predictors of quality of life and of subjective well-being in chronic Portuguese patients. METHODS: Chronic disease patients (n = 774) were recruited from central Portuguese Hospitals. Participants completed self-reported questionnaires assessing socio-demographic, clinical, psychosocial and outcome variables: quality of life (HRQL) and subjective well-being (SWB). MANCOVA analyses were used to test psychosocial factors as determinants of HRQL and SWB. RESULTS: After controlling for socio-demographic and clinical variables, results showed that dispositional optimism, positive affect, spirituality, social support and treatment adherence are significant predictors of HRQL and SWB. Similar predictors of quality of life, such as positive affect, treatment adherence and spirituality, were found for subgroups of disease classified by medical condition. CONCLUSIONS: The work identifies psychosocial factors associated with quality of life. The predictors for the entire group of different chronic diseases are similar to the ones found in different chronic disease subgroups: positive affect, social support, treatment adherence and spirituality. Patients with more positive affect, additional social support, an adequate treatment adherence and a feel-good spirituality, felt better with the disease conditions and consequently had a better quality of life. This study contributes to understanding and improving the processes associated with quality of life, which is relevant for health care providers and chronic diseases support.This study was supported by a grant from the Fundação para a Ciência e Tecnologia (PTDC/PSI/71635/2006, PTDC/PSI/ 73175/2006, SFRH/PROTEC/49284/2008

Stigma and obesity: comparative study between candidates to obesity surgery and patients already submitted to this treatment

Baratte François. Un trésor d'argenterie découvert en Asie centrale. In: Bulletin de la Société Nationale des Antiquaires de France, 2001, 2006. pp. 176-177

Contactos selectivos : uma via para a alta eficiência de células solares de silício cristalino

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: Podemos identificar 5 linhas de acção na tecnología de células solares baseadas em silício cristalino: (1) Migração da célula de Al BSF para células com tecnologia p-type PERC/n-type PERT, (2) células com contactos traseiros (IBC), (3) células com heterojunções (HET), (4) introdução de contactos passivantes e (5) novas células tandem baseadas em perovskites ou materiais III-V. A arquitectura da célula solar proposta no projecto SELCON segue a linha 4 acima apontada, e demonstrou já eficiências também acima de 25%, introduzindo os contactos selectivos mas mantendo uma arquitectura semelhante à que existe na indústria, com contactos opostos e sem padrões de texturização. A estrutura proposta incorpora junções selectivas (CSJs) que permitem ultrapassar a maior limitação das células actuais – as perdas por recombinação – extraindo eficientemente as cargas geradas na célula solar. Neste trabalho foi estudada a melhor alternativa de passivação usando camadas de SiO2/TiO2 tendo-se observado que a oxidação térmica a 900 ºC tem passivação inferior ao óxido térmico a 775ºC.ABSTRACT: We can identify 5 lines of action for silicon solar cells technology: (1) Migration from the Al BSF cell to p-type PERC/n-type PERT, (2) solar cells with back contacts (IBC), (3) heterojunction solar cells (HET), (4) selective contacts introduction and (5) new tandem solar cells based on perovskites or III-V materials. The architecture proposed by the SELCON Project follows the path (4), with demonstrated efficiencies above 25%, introducing selective contacts while keeping a planar structure with oposite contacts. The proposed structure, with selective contacts, will make posible the overcome the main limitation in todays cells – recombination losses – by efficiently extracting the generated charges inside the solar cell. In this work, the best passivation method was evaluated, and we show that the best option is to use a stack of SiO2/TiO2, using thermal silicon oxide obtained at 775 ºC.info:eu-repo/semantics/publishedVersio

Melhoramento ótico de células solares tandem com base em silício cristalino

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: A estratégia mais promissora para reduzir o custo da eletricidade fotovoltaica é o aumento da eficiência dos sistemas. As células de silício cristalino estão cada vez mais próximas do seu limite teórico de eficiência, sendo por isso progressivamente mais difícil aumentar a sua de eficiência. As células solares tandem com base em silício cristalino são um dos caminhos mais promissores para atingir uma eficiência de conversão para além dos 30% com um custo competitivo. Neste artigo é apresentada uma proposta de célula tandem com base em silício cristalino de com três terminais em que as subcélulas são ligadas em paralelo, sendo também propostas algumas estratégias para melhorar as propriedades óticas deste dispositivo. São apresentados os resultados do desenvolvimento de um método de melhoramento do desempenho ótico do silício cristalino, baseado em gravação química assistida por metal, e de simulações numéricas de dispositivos.ABSTRACT: The most promising strategy to reduce the cost of photovoltaic electricity is to increase the systems’ efficiency. Crystalline silicon cells are getting closer to their theoretical efficiency limit, which is why it is progressively more difficult to increase their efficiency. Crystalline silicon-based tandem solar cells are one of the most promising ways to achieve conversion efficiency beyond 30% at a competitive cost. This article presents a proposal for a tandem cell based on crystalline silicon with three terminals in which the subcells are connected in parallel, and some strategies to improve the optical properties of this device are proposed. The results of the development of a method to improve the optical performance of crystalline silicon, based on metal-assisted chemical etching and numerical device simulations’ results are presented.info:eu-repo/semantics/publishedVersio

Interconexão entre células solares de perovskita e silício em dispositivos monolíticos Tandem de 2 terminais : estado da arte e desenvolvimentos futuros

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: A formação de uma junção de efeito túnel é um fator chave para atingir altas eficiências em células solares tandem. As técnicas reportadas para a formação de junções de silício em dispositivos monolíticos tandem de 2 terminais como a Deposição Química de Vapor Assistida por Plasma (PECVD) ou a Implantação Iónica possuem restrições do ponto de vista de custos ou de aplicação ao nível industrial. A alternativa em estudo assenta na aplicação da técnica de dopagem por laser para a fabricação de junções de efeito túnel de silício com elevado grau de cristalinidade. Para isso desenvolveu-se um setup que recorre a um laser pulsado com emissão na região do infravermelho Nd:YAG (1064nm) para fusão superficial do silício e à utilização de oxicloreto de fósforo (POCl3) como fonte de dopante. O laser está acoplado a uma cabeça galvanométrica com lente f-teta de forma a permitir redireccionar e focar o feixe na superfície da amostra. O processo em causa possui várias vantagens face a outros já utilizados, uma vez que é facilmente escalável, rápido, com potencial baixo custo de processamento e eficiente do ponto de vista energético.ABSTRACT: The formation of a junction with tunneling effect is a key factor to achieve high efficiencies in tandem solar cells. The techniques reported for the formation of silicon junctions in 2-terminal tandem monolithic devices such as Plasma Assisted Vapor Chemical Deposition (PECVD) or Ionic Implantation have cost and application constrains at the industrial level. The alternative under study is based on the application of the laser doping technique for the manufacture of a silicon tunnel junction with a high degree of crystallinity. For this, a setup was developed using a pulsed laser with emission in the infrared region Nd:YAG (1064nm) for shallow surface melting of the silicon wafer and the use of phosphorus oxychloride (POCl3) as a source of dopant. The laser is coupled to a galvanometric head with a f-theta lens to allow redirecting and focusing the beam on the surface of the sample. This process has several advantages compared to others, since it is easily scalable, fast, energy efficient while presenting potentially low processing costs.info:eu-repo/semantics/publishedVersio