12 resultados para SUB-POPULATIONS
em Repositório Científico do Instituto Politécnico de Lisboa - Portugal
Resumo:
A satisfação profissional tem vindo a ser descrita como o estado emocional positivo resultante do prazer que se tem com as experiências do trabalho, estando intrinsecamente relacionada com factores como desempenho profissional, saúde física e mental e com a auto-estima do trabalhador. Neste estudo pretende-se estudar o nível de satisfação profissional dos Técnicos de Anatomia Patológica, Citológica e Tanatológica (APCT) que desempenham funções nos hospitais públicos e de gestão S.A. da Sub-Região de Lisboa. A satisfação profissional foi classificada quantitativamente, segundo as abordagens baseadas na discrepância entre expectativas e resultados. Para tal, recorreu-se a um questionário validado que compreende itens passíveis de medir a satisfação profissional global e as suas dimensões - Remuneração, Segurança no Emprego,Condições de Trabalho & Saúde, Relações de Trabalho & Suporte Social, Status & Prestígio, Autonomia & Poder e Realização Pessoal e Profissional & Desempenho Organizacional, permitindo ainda verificar a Importância Motivacional que os técnicos inquiridos atribuem a cada uma destas. O referido instrumento de medida continha também uma questão aberta para sugestões dos técnicos, de forma a melhorar a sua satisfação profissional. O score de Satisfação Profissional Global dos inquiridos é relativamente elevado. Em relação às dimensões abordadas, os resultados revelam que os técnicos se encontram mais satisfeitos com Status & Prestígio e menos satisfeitos com Remuneração. Em relação à ordenação das dimensões segundo a Importância Motivacional, a Realização Pessoal e Profissional & Desempenho Organizacional é considerada a mais importante, sendo a mais focada nas sugestões apresentadas pelos inquiridos para a melhoria da sua satisfação, enquanto que Status & Prestígio será a menos importante. Verificam-se diferenças estatisticamente significativas entre os técnicos pertencentes ao Quadro (no geral, os menos satisfeitos) e aqueles que não pertencem, em relação à maioria das dimensões e à Satisfação Profissional Global; bem como entre os Licenciados e os Não Licenciados, que estão menos satisfeitos em relação à dimensão Status & Prestígio.
Resumo:
New K/Ar dating and geochemical analyses have been carried out on the WNW-ESE elongated oceanic island of S. Jorge to reconstruct the volcanic evolution of a linear ridge developed close to the Azores triple junction. We show that S. Jorge sub-aerial construction encompasses the last 1.3 Myr, a time interval far much longer than previously reported. The early development of the ridge involved a sub-aerial building phase exposed in the southeast end of the island and now constrained between 1.32 +/- 0.02 and 1.21 +/- 0.02 Ma. Basic lavas from this older stage are alkaline and enriched in incompatible elements, reflecting partial melting of an enriched mantle source. At least three differentiation cycles from alkaline basalts to mugearites are documented within this stage. The successive episodes of magma rising, storage and evolution suggest an intermittent reopening of the magma feeding system, possibly due to recurrent tensional or trans-tensional tectonic events. Present data show a gap in sub-aerial volcanism before a second main ongoing building phase starting at about 750 ka. Sub-aerial construction of the S. Jorge ridge migrated progressively towards the west, but involved several overlapping volcanic episodes constrained along the main WNW-ESE structural axis of the island. Malic magmas erupted during the second phase have been also generated by partial melting of an enriched mantle source. Trace element data suggest, however, variable and lower degrees of partial melting of a shallower mantle domain, which is interpreted as an increasing control of lithospheric deformation on the genesis and extraction of primitive melts during the last 750 kyr. The multi-stage development of the S. Jorge volcanic ridge over the last 1.3 Myr has most likely been greatly influenced by regional tectonics, controlled by deformation along the diffuse boundary between the Nubian and the Eurasian plates, and the increasing effect of sea-floor spreading at the Mid-Atlantic Ridge.
Resumo:
The mis-evaluation of risk in securitized financial products is central to understanding the global financial crisis. This paper characterizes the evolution of risk factors affecting collateralized debt obligations (CDOs) based on subprime mortgages. A key feature of subprime mortgage-backed indices is that they are distinct in their vintage of issuance. Using a latent factor framework that incorporates this vintage effect, we show the increasing importance of common factors on more senior tranches during the crisis. An innovation of the paper is that we use the unbalanced panel structure of the data to identify the vintage, credit, common and idiosyncratic effects from a state-space specification.
Resumo:
O vasoespasmo constitui uma das principais complicações pós Hemorragia Sub-Aracnoideia, detendo um elevado impacto a nível clínico e social, nomeadamente em termos de mortalidade e morbilidade. Esta patologia, quando sintomática, é definida como uma deterioração aguda do estado neurológico, na ausência de outras possíveis causas, sejam elas estruturais, metabólicas ou infecciosas. A evolução do vasoespasmo constitui um processo dinâmico, pelo que a sua avaliação é essencial. É neste âmbito que a Ultrassonografia, através do Doppler Transcraniano, assume um papel de destaque, quer no diagnóstico e follow-up, quer na orientação da terapêutica. A realização deste caso clínico tem como principal objectivo demonstrar o elevado valor diagnóstico e consequentemente mais-valia do Doppler Transcraniano na avaliação e follow-up do vasoespasmo pós Hemorragia Sub-Aracnoideia.
Resumo:
Cyanobacteria are prokaryotic, plantlike organisms present in lakes, recreational waters, and reservoirs, and often dominate phytoplankton communities in warm, nutrient-enriched hard waters. A stable water column rich in certain nutrients, especially nitrogen and phosphorus, is associated with favorable environmental conditions that support development of cyanobacterial population maxima or "blooms." Under specific conditions, cyanobacteria produce toxins that are responsible for acute poisoning and death of animals and humans. The main aim of this study was to correlate the presence of cyanobacteria blooms with potential toxicity to humans as a public health issue. In Portugal, seven reservoirs located in the southern region were selected and studied between 2000 and 2008. Reservoirs were characterized by physical and chemical aspects, and identification of phytoplankton communities. In the case of cyanobacterial blooms, toxins that affected the liver, nervous system, and skin were detected, namely, Microcystis aeruginosa, Aphanizomenon spp., and Oscillatoria. These findings suggest the presence of a potential risk for public health, and indicate the need to implement mitigation measures in all studied reservoirs. These measures may involve (1) water eutrophication control to avoid blooms, (2) appropriate treatment of water for human consumption, and (3) public warnings or information to those individuals that use these reservoirs for several recreational activities.
Resumo:
A institucionalização do direito à saúde, na constituição de 1976, como direito social e humano não parece ter conseguido, na prática dos profissionais de saúde, abalar a relação paternalista que coloca o doente numa situação de submissão face à dominância do poder/saber médico central ou periférico que o doente, nos termos de Parsons, deve acatar humildemente como “um bom doente”. É este papel de passividade e submissão do doente que nos propomos problematizar nos meandros dos direitos humanos/direitos sociais de cidadania como campo de construção social assente em práticas norteadas por direitos e deveres que, nos termos de Foucault, submetem os cidadãos a constrangimentos inerentes às relações de poder.
Resumo:
We report the fabrication of planar sub-micron gratings in silicon with a period of 720 nm using a modified Michelson interferometer and femtosecond laser radiation. The gratings consist of alternated stripes of laser ablated and unmodified material. Ablated stripes are bordered by parallel ridges which protrude above the unmodified material. In the regions where ridges are formed, the laser radiation intensity is not sufficient to cause ablation. Nevertheless, melting and a significant temperature increase are expected, and ridges may be formed due to expansion of silicon during resolidification or silicon oxidation. These conclusions are consistent with the evolution of the stripes morphology as a function of the distance from the center of the grating. (C) 2013 Elsevier Ltd. All rights reserved.
Resumo:
Mestrado em Contabilidade
Resumo:
Relatório de Estágio para obtenção do grau de Mestre em Engenharia na Área de Especialização em Edificações
Resumo:
A swift chemical route to synthesize Co-doped SnO2 nanopowders is described. Pure and highly stable Sn1-xCoxO2-delta (0 <= x <= 0.15) crystalline nanoparticles were synthesized, with mean grain sizes <5 nm and the dopant element homogeneously distributed in the SnO2 matrix. The UV-visible diffuse reflectance spectra of the Sn1-xCoxO2-delta samples reveal red shifts, the optical bandgap energies decreasing with increasing Co concentration. The samples' Urbach energies were calculated and correlated with their bandgap energies. The photocatalytic activity of the Sn1-xCoxO2-delta samples was investigated for the 4-hydroxylbenzoic acid (4-HBA) degradation process. A complete photodegradation of a 10 ppm 4-HBA solution was achieved using 0.02% (w/w) of Sn0.95Co0.05O2-delta nanoparticles in 60 min of irradiation. (C) 2014 Elsevier B.V. All rights reserved.
Resumo:
Density-dependent effects, both positive or negative, can have an important impact on the population dynamics of species by modifying their population per-capita growth rates. An important type of such density-dependent factors is given by the so-called Allee effects, widely studied in theoretical and field population biology. In this study, we analyze two discrete single population models with overcompensating density-dependence and Allee effects due to predator saturation and mating limitation using symbolic dynamics theory. We focus on the scenarios of persistence and bistability, in which the species dynamics can be chaotic. For the chaotic regimes, we compute the topological entropy as well as the Lyapunov exponent under ecological key parameters and different initial conditions. We also provide co-dimension two bifurcation diagrams for both systems computing the periods of the orbits, also characterizing the period-ordering routes toward the boundary crisis responsible for species extinction via transient chaos. Our results show that the topological entropy increases as we approach to the parametric regions involving transient chaos, being maximum when the full shift R(L)(infinity) occurs, and the system enters into the essential extinction regime. Finally, we characterize analytically, using a complex variable approach, and numerically the inverse square-root scaling law arising in the vicinity of a saddle-node bifurcation responsible for the extinction scenario in the two studied models. The results are discussed in the context of species fragility under differential Allee effects. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
We report the fabrication of planar sub-micron gratings in silicon with a period of 720 nm using a modified Michelson interferometer and femtosecond laser radiation. The gratings consist of alternated stripes of laser ablated and unmodified material. Ablated stripes are bordered by parallel ridges which protrude above the unmodified material. In the regions where ridges are formed, the laser radiation intensity is not sufficient to cause ablation. Nevertheless, melting and a significant temperature increase are expected, and ridges may be formed due to expansion of silicon during resolidification or silicon oxidation. These conclusions are consistent with the evolution of the stripes morphology as a function of the distance from the center of the grating.