6 resultados para Mobility and roaming

em Repositório Científico da Universidade de Évora - Portugal


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Nitrobenzoxadiazole (NBD)-labeled lipids are popular fluorescent membrane probes. However, the understanding of important aspects of the photophysics of NBD remains incomplete, including the observed shift in the emission spectrum of NBD-lipids to longer wavelengths following excitation at the red edge of the absorption spectrum (red-edge excitation shift or REES). REES of NBD-lipids in membrane environments has been previously interpreted as reflecting restricted mobility of solvent surrounding the fluorophore. However, this requires a large change in the dipole moment (Dm) of NBD upon excitation. Previous calculations of the value of Dm of NBD in the literature have been carried out using outdated semi-empirical methods, leading to conflicting values. Using up-to-date density functional theory methods, we recalculated the value of Dm and verified that it is rather small (B2 D). Fluorescence measurements confirmed that the value of REES is B16 nm for 1,2-dioleoyl-sn-glycero-3- phospho-L-serine-N-(NBD) (NBD-PS) in dioleoylphosphatidylcholine vesicles. However, the observed shift is independent of both the temperature and the presence of cholesterol and is therefore insensitive to the mobility and hydration of the membrane. Moreover, red-edge excitation leads to an increased contribution of the decay component with a shorter lifetime, whereas time-resolved emission spectra of NBD-PS displayed an atypical blue shift following excitation. This excludes restrictions to solvent relaxation as the cause of the measured REES and TRES of NBD, pointing instead to the heterogeneous transverse location of probes as the origin of these effects. The latter hypothesis was confirmed by molecular dynamics simulations, from which the calculated heterogeneity of the hydration and location of NBD correlated with the measured fluorescence lifetimes/REES. Globally, our combination of theoretical and experiment-based techniques has led to a considerably improved understanding of the photophysics of NBD and a reinterpretation of its REES in particular.

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"A Administração Pública visa a prossecução do interesse público, no respeito pelos direitos e interesses legalmente protegidos dos Cidadãos" (art.º266 Constituição da República Portuguesa). Este estudo subordinado ao tema: "Satisfação dos utilizadores de um Serviço Público - Caso: Direcção Regional de Mobilidade e Transportes do Alentejo” centra-se na investigação, da satisfação e percepção do utilizador dos serviços, na sequência da sua utilização, como forma de satisfazer as suas necessidades. Esta investigação foi desenvolvida em duas partes, a primeira reflecte uma pesquisa teórica sobre a temática, objecto de estudo. A segunda, incidiu na análise e no tratamento dos dados, obtidos através de um questionário, distribuído aos utilizadores da D.R.M.T. Alentejo (Évora, Beja e Portalegre). /ABSTRACT: "The Government aims to further the public interest, while respecting the rights and legally protected interests of citizens" (Article 266 Constitution ofthe Portuguese). This study entitled "Users Satisfaction of a Public Service - Case: Regional Direction of Mobility and Transports of Alentejo" focuses on research, customer satisfaction and perception of the service user, following its use as a way to meet their needs. This research was conducted in two parts, the first reflects a theoretical research on the subject, the subject of study. The second, focused on analyzing and processing data, obtained through a questionnaire distributed to users.

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Walking is the most basic form of transportation. A good understanding of pedestrian’s dynamics is essential in meeting the mobility and accessibility needs of people by providing a safe and quick walking flow. Advances in the dynamics of pedestrians in crowds are of great theoretical and practical interest, as they lead to new insights regarding the planning of pedestrian facilities, crowd management, or evacuation analysis. As a physicist, I would like to put forward some additional theoretical and practical contributions that could be interesting to explore, regarding the perspective of physics on about human crowd dynamics (panic as a specific form of behavior excluded).

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A questão central que abordamos nesta tese, assenta na génese do pensamento portátil dos nossos objectos não artísticos e artísticos. A portabilidade como sintoma civilizacional, num contexto de crescente mobilidade e transição para modos de vida nómadas e itinerantes nas suas mais heterogéneas expressões. Especula-se, que a génese desta mutação nos estilos de vida que são vertiginosamente acompanhados pela parafernália de objectos que orbitam em nossa volta, numa espiral crescente de portabilidade, esteja na necessidade de busca de novos paradigmas societais, após a falência daqueles que sustentam este modo de vida artificial. ABSTRACT: The central question boarded in this thesis, leys on the genesis of the portability's thought about objects, artistic and non-artistic ones. Portability is seen as a civilizational symptom, in a growing context of mobility and transition to nomadic and itinerant ways of life, in there most heterogeneous manifestations. We speculate that the genesis of this mutation of life styles, that are vertiginously accompanied by all this paraphernalia of objects that orbit around us in a crescent spiral of portability, leys on the necessity to search new social paradigms, after the fall of those that sustain these artificial ways of life.

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Knee osteoarthritis is the most common type of arthritis and a major cause of impaired mobility and disability for the ageing populations. Therefore, due to the increasing prevalence of the malady, it is expected that clinical and scientific practices had to be set in order to detect the problem in its early stages. Thus, this work will be focused on the improvement of methodologies for problem solving aiming at the development of Artificial Intelligence based decision support system to detect knee osteoarthritis. The framework is built on top of a Logic Programming approach to Knowledge Representation and Reasoning, complemented with a Case Based approach to computing that caters for the handling of incomplete, unknown, or even self-contradictory information.

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This special issue reports some of the highlights of the conference Living Landscape – The European Landscape Convention in Research Perspective, organised jointly by UNISCAPE and Landscape Europe (UNISCAPE, 2010). Starting questions for this conference were: what has science contributed to the implementation of the European Landscape Convention (CoE, 2000) and what are the topics for the future of European landscape? The 10th anniversary of the Florence Convention in October 2010 was an opportunity to discuss the merits of landscape science in integrated research of a rapidly changing environment. Many interdisciplinary contributions presented referred to the Landscape Convention. The conference focused on cutting-edge research results at the crossroads of sciences and humanities, design and empiricism. Not by chance, the conference was also the occasion to launch a new ESF-COST Science-Policy Briefing on Landscape Research (Bloemers, Daniels, Fairclough, Pedroli, & Stiles, 2010 Bloemers, T., Daniels, S., Fairclough, G., Pedroli, B., & Stiles, R. (Eds.) (2010) Landscape in a changing world. Bridging Divides, integrating disciplines, serving society. Science Policy Briefing nr 41. Strasbourg and Brussels: ESF-COST. ): ‘Landscape in a Changing World – Bridging Divides, Integrating Disciplines, Serving Society’. It emphasises the importance of four interdisciplinary themes: Universal commons: securing landscape as a common good. Roots and routes: coming to terms with mobility and evolving lifestyles. Reactions and resilience: long-term landscape transformations. Road maps: landscape as baseline and context for future change. The papers in this special issue largely reflect these themes.