8 resultados para double perovskite spin polarization point contact spectrocopy


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Biochemistry, 2011, 50 (20), pp 4251–4262 DOI: 10.1021/bi101605p

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A Work Project, presented as part of the requirements for the Award of a Master’s Double Degree in Finance from Maastricht University and NOVA – School of Business and Economics

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Retinal imaging with a confocal scaning laser Ophthalmoscope (cSLO) involves scanning a small laser beam over the retina and constructing an image from the reflected light. By applying the confocal principle, tomographic images can be produced by measuring a sequence of slices at different depths. However, the thickness of such slices, when compared with the retinal thickness, is too large to give useful 3D retinal images, if no processing is done. In this work, a prototype cSLO was modified in terms hardware and software to give the ability of doing the tomographic measurements with the maximum theoretical axial resolution possible. A model eye was built to test the performance of the system. A novel algorithm has been developed which fits a double Gaussian curve to the axial intensity profiles generated from a stack of images slices. The underlying assumption is that the laser light has mainly been reflected by two structures in the retina, the internal limiting membrane and the retinal pigment epithelium. From the fitted curve topographic images and novel thickness images of the retina can be generated. Deconvolution algorithms have also been developed to improve the axial resolution of the system, using a theoretically predicted cSLO point spread function. The technique was evaluated using measurements made on a model eye, four normal eyes and seven eyes containing retinal pathology. The reproducibility, accuracy and physiological measurements obtained, were compared with available published data, and showed good agreement. The difference in the measurements when using a double rather than a single Gaussian model was also analysed.

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(l) The Pacific basin (Pacific area) may be regarded as moving eastwards like a double zip fastener relative to the continents and their respective plates (Pangaea area): opening in the East and closing in the West. This movement is tracked by a continuous mountain belt, the collision ages of which increase westwards. (2) The relative movements between the Pacific area and the Pangaea area in the W-EfE-W direction are generated by tidal forces (principle of hypocycloid gearing), whereby the lower mantle and the Pacific basin or area (Pacific crust = roof of the lower mantle?) rotate somewhat faster eastwards around the Earth's spin axis relative to the upper mantle/crust system with the continents and their respective plates (Pangaea area) (differential rotation). (3) These relative West to East/East to West displacements produce a perpetually existing sequence of distinct styles of opening and closing oeean basins, exemplified by the present East to West arrangement of ocean basins around the globe (Oceanic or Wilson Cycle: Rift/Red Sea style; Atlantic style; Mediterranean/Caribbean style as eastwards propagating tongue of the Pacific basin; Pacific style; Collision/Himalayas style). This sequence of ocean styles, of which the Pacific ocean is a part, moves eastwards with the lower mantle relative to the continents and the upper-mantle/crust of the Pangaea area. (4) Similarly, the collisional mountain belt extending westwards from the equator to the West of the Pacific and representing a chronological sequence of collision zones (sequential collisions) in the wake of the passing of the Pacific basin double zip fastener, may also be described as recording the history of oceans and their continental margins in the form of successive Wilson Cycles. (5) Every 200 to 250 m.y. the Pacific basin double zip fastener, the sequence of ocean styles of the Wilson Cycle and the eastwards growing collisional mountain belt in their wake complete one lap around the Earth. Two East drift lappings of 400 to 500 m.y. produce a two-lap collisional mountain belt spiral around a supercontinent in one hemisphere (North or South Pangaea). The Earth's history is subdivided into alternating North Pangaea growth/South Pangaea breakup eras and South Pangaea growth/North Pangaea breakup eras. Older North and South Pangaeas and their collisional mountain belt spirals may be reconstructed by rotating back the continents and orogenic fragments of a broken spiral (e.g. South Pangaea, Gondwana) to their previous Pangaea growth era orientations. In the resulting collisional mountain belt spiral, pieced together from orogenic segments and fragments, the collision ages have to increase successively towards the West. (6) With its current western margin orientated in a West-East direction North America must have collided during the Late Cretaceous Laramide orogeny with the northern margin of South America (Caribbean Andes) at the equator to the West of the Late Mesozoic Pacific. During post-Laramide times it must have rotated clockwise into its present orientation. The eastern margin of North America has never been attached to the western margin of North Africa but only to the western margin of Europe. (7) Due to migration eastwards of the sequence of ocean styles of the Wilson Cycle, relative to a distinct plate tectonic setting of an ocean, a continent or continental margin, a future or later evolutionary style at the Earth's surface is always depicted in a setting simultaneously developed further to the West and a past or earlier style in a setting simultaneously occurring further to the East. In consequence, ahigh probability exists that up to the Early Tertiary, Greenland (the ArabiaofSouth America?) occupied a plate tectonic setting which is comparable to the current setting of Arabia (the Greenland of Africa?). The Late Cretaceous/Early Tertiary Eureka collision zone (Eureka orogeny) at the northern margin of the Greenland Plate and on some of the Canadian Arctic Islands is comparable with the Middle to Late Tertiary Taurus-Bitlis-Zagros collision zone at the northern margin of the Arabian Plate.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia do Ambiente, Perfil Gestão e Sistemas Ambientais

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IET Control Theory & Applications, Vol. 1, Nº 1

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RESUMO - A 8 de Maio de 2008 surgiu o centro de atendimento “Linha Saúde24” (S24) no sentido de modernizar o SNS, aproximando-o do cidadão. O serviço surge baseado no modelo inglês – o NHS Direct – que pode ser encarado como um serviço de informação telefónico apoiado por enfermeiros, disponível 24h por dia, concebido para expandir os serviços púbicos de acesso à rede prestadora de cuidados com intuito de aliviar a pressão da procura na rede de urgências hospitalares e médicos de família, assim como diluir as iniquidades regionais na prestação de serviços. A S24 assenta na perspectiva de ser um ponto de contacto inicial do utente com a rede de prestação de cuidados de saúde com capacidade de orientação. O objectivo da linha está na tentativa mais eficiente no uso dos recursos disponíveis, ao mesmo tempo que delega responsabilidade no cidadão na forma como este utiliza os recursos disponíveis, com melhor racionalização financeira na área da saúde aliada a uma melhor qualidade de serviço prestada e adequada, colocando os cidadãos no mesmo patamar, diluindo as dificuldades de acesso a aqueles que necessitam na tentativa de harmonizar e racionalizar o consumo de serviços de saúde. Esta estrutura permite ao cidadão conhecer melhor o seu estado de saúde e decidir mais acertadamente quanto à decisão a tomar. Com este estudo, e com base na literatura nacional e internacional, pretende-se descrever o perfil de utilizador que acede à S24 – definir o tipo de utilizador, disposição geográfica, motivos pelo qual acede ao serviço e qual o seu destino final, fazendo comparação com o perfil do NHS Direct. Assim, e com os dados obtidos, far-se-á uma avaliação preliminar em termos do contributo da linha S24 no que concerne à sua eficiência, equidade e empowerment dado ao utilizador. --- ------------------------------ABSTRACT - Saúde 24 (S24) is a national 24-hour health line initiated in May 2008 aiming at modernizing the Portuguese NHS by bringing it closer to the citizen. Indeed, S24 be seen as an initial contact point between the patient and the healthcare network, facilitating a better a management of health care demand. The service is inspired on the UK NHS Direct – a nurse-led telephone line to provide easier and faster advice information to people about health, illness and NHS services. It is expected to provide information so that people can deal with their health problems or their families´ on their own, with the purpose of reducing demand to A&E department and out-of-hours GP services. Additionally it can contribute to a reduction in regional inequities in healthcare provision through bringing health care advice to remote areas. The purpose of S24 is to handle more efficiently the available resources by enabling responsibilities in citizens. By doing so, S24 encourages a more appropriate use of available resources, with better financial outcomes and a better quality of care. It is meant, in terms of empowerment, to help people to be in control of their health and healthcare interactions by participating in the final decision. Based on quantitative data, this study defines the S24 caller user profile in terms of type, geographical reference, reasons for calling and outcome. This analysis allows us to perform a preliminary evaluation of the S24 in terms of its contribution to efficiency, equity and empowerment. Then the S24 is compared to