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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Programs to promote physical activity among children and adolescents : a case study of the Team Bath Tribe Project

Koorts, Harriet January 2012 (has links)
Background: Physical inactivity has been identified as the fourth leading risk factor for global mortality. Despite public health guidelines advising children and adolescents to spend a minimum of 60 minutes per day of at least moderate intensity physical activity, a large proportion of children and adolescents fail to meet these guidelines. Interventions promoting physical activity show varying degrees of success, and more detailed evaluations of such interventions are essential. The aim of this research was to conduct an in-depth evaluation of a community-based physical activity program aimed at children and adolescents, specifically the Tribe Project. Methods: The RE-AIM framework (Reach, Effectiveness, Adoption, Implementation and Maintenance) was used to evaluate the individual and organisational-level impact of the Tribe Project. A single mixed method case study was used based on five sources of evidence: interviews, questionnaires, documentation, archival records and direct observations. Participants included the Tribe managers and coaches implementing the program and the Tribe parents and children/adolescents who attended. Results: The Tribe Project reached approximately 2.5% of the eligible population living within Bath and North East Somerset. The program successfully met some of its objectives although feedback procedures were poor and the program aims were unclear. The community-level adoption of the program was high, however, the implementation and adherence to the program principles at the setting-level varied. The program was successfully institutionalised within the University of Bath yet pathways after the program into the community varied, and were mostly competitive only. Nonetheless, a combination of social, psychological and physical benefits was reported following participation. Conclusion: To assess accurately the potential impact of physical activity interventions a combined assessment of individual and organisational-level factors is necessary. This will help inform policy on effective strategies to promote physical activity in the community, and develop interventions that are more effective as a result.
192

Is the epidermal growth factor receptor involved in visual system regenerative failure?

Morrison, Kevin Carlo January 2011 (has links)
Introduction: A study in 2005 found that Epidermal Growth Factor Kinase Inhibitors (EGFRki) could promote Retinal Ganglion Cell (RGC) axonal regeneration in vivo when delivered to the crushed Optic Nerve (ON). The axon regenerative effects of these EGFRki were attributed to their blockade of the Epidermal Growth Factor Receptor (EGFR), and EGFR activation was hence suggested to lead to growth cone collapse and failed RGC axon regeneration. Aims: To investigate the role of EGFR in RGC axonal regenerative failure, and to elucidate the mechanisms of action by which EGFRki promote RGC axonal regeneration. Methods: Immunohistochemistry and immunocytochemistry to visualize activated EGFR (pEGFR) Primary retinal cultures to examine the actions of EGFRki such as AG1478 on RGC in vitro. ELISA to examine the conditioned media from these cultures for NeuroTrophic Factors (NTF). Intravitreal (ivit) injections of EGFRki (PD168393) into Optic Nerve Crush (ONC) recipient rats to attempt to elicit in vivo regeneration. The implantation of PD168393-impregnated collagen matrices into ONC recipient rats to attempt to elicit in vivo regeneration. PCR on retinal lysates to detect NTF mRNA. Results: No pEGFR was detected on RGC axons, either in the retina or in the ON of any treatment or control group. pEGFR was detected on almost all ON and retinal glial types prior to injury and almost all glial types exhibited increased pEGFR levels post-ONC. A sub population (~30%) of RGC cell bodies were pEGFR+ but this proportion did not change between control and treatment groups. AG1478 was shown to disinhibit RGC in Nogo-P4 inhibited primary retinal cultures but ELISA on conditioned media for various NTF detected none, however PCR detected mRNA for several of these NTF in retinal lysates. Ivit PD168393 failed to elicit RGC survival or axonal regeneration in vivo. Intra ON implantation of PD168393 impregnated collagen matrices appeared to promote significant RGC axonal regeneration post-ONC, but did not affect RGC survival. Discussion: Several models explaining the in vitro regenerative and in vivo neuritogenic actions of EGFRki were developed. These included the abrogation of various harmful glially mediated processes, the stimulation of NTF release by local glia and the stimulation or blockade of several other non-EGFR dependent signalling cascades by EGFRki. Conclusions: The axogenic and neuritogenic actions of EGFRki in vitro and in vivo were confirmed. The identification of numerous other means by which EGFRki could indirectly promote RGC axonal regeneration, including by acting on targets other than EGFR allowed the construction of a combinatorial model of how EGFRki effect axonal regeneration, and the original hypothesis positing EGFR as an intra-axonal component of a growth cone collapsing signalling cascade was disgarded.
193

A novel paradigm to identify age- and stroke-related changes to gaze behaviour associated with falls risk during walking

Stanley, Jennifer January 2013 (has links)
This thesis aimed to investigate a novel way to explore changes in gaze behaviour, whilst walking, in frail populations. Initially three studies were conducted to establish how similar gaze behaviour recorded during walking was to that recorded whilst scene viewing. Duration of time and number of times different features were fixated were found to be similar in the three experiments. Older adults were assessed for falling risk and split into higher risk of falling (HROA) and lower risk of falling (LROA) groups. Their gaze behaviour was recorded whilst scene viewing along with a group of young adults. HROA were found to fixate the travel path longer than LROA and younger adults. HROA were slower at completing the incongruent Stroop task, suggesting a relationship between response inhibition and increased falling risk. A group of stroke patients were assessed for falling risk and split according to lesion location (parietal, occipital or frontal-temporal); gaze behaviour was recorded during scene viewing and compared to controls. Observable differences, which related to falling risk and lesion location, were shown in the gaze behaviour of the stroke patients compared to the controls. The findings of this thesis suggest that scene viewing could be used to better inform us about the changes in gaze behaviour which occur in frail populations that led to an increased risk of falling and the cognitive mechanisms which underlie these changes than laboratory studies.
194

Apoio à documentação de engenharia reversa de software por meio de hipertextos.

Feltrim, Valéria Delisandra 09 December 1999 (has links)
O crescimento do mercado de software a cada dia acarreta o aumento do uso de técnicas de desenvolvimento, muitas vezes informais. A manutenção de tais softwares torna-se problemática, uma vez que a documentação associada ao software, na maioria das vezes, não está de acordo com o código implementado. Dessa forma, quando diante da manutenção do produto, o engenheiro de software encontra uma documentação informal e incompleta, que não reflete o software existente. Nesse contexto é que se encontra a Engenharia Reversa de Software, com o propósito de recuperar as informações de projeto perdidas durante a fase de desenvolvimento, e de documentar o real estado do software. O principal objetivo deste trabalho de mestrado foi a investigação de uma estrutura adequada de hiperdocumento para apoiar a documentação requerida durante o processo de engenharia reversa de software. A partir de um levantamento dos requisitos desejáveis em um hiperdocumento, para que possua as habilidades de suporte à documentação de engenharia de reversa de software, um conjunto de links e estrutura de nós foi definido. Os requisitos, para a composição de tal hiperdocumento, foram investigados por meio de uma experiência: a autodocumentação do sistema hipermídia denominado SASHE (Sistema de Autoria e Suporte Hipermídia para Ensino), que já possui suporte ao tratamento de nós aninhados e outras características de aplicativo para ensino. A engenharia reversa foi desenvolvida baseando-se no método de engenharia reversa Fusion-RE/I, e os produtos obtidos foram inseridos em uma hiperbase no SASHE.
195

Obtenção de radiografia industrial digital de alta resolução utilizando radiação sincroton e imaging plate

Kazuki Cardoso Taguchi, Sandro January 2004 (has links)
Made available in DSpace on 2014-06-12T17:41:13Z (GMT). No. of bitstreams: 3 arquivo7696_1.pdf: 7594338 bytes, checksum: 33dade33cb87270be25cf71d4b8bc733 (MD5) arquivo7696_2.pdf: 1840140 bytes, checksum: f115d95a1f4b18e50d40a44ea5ee1117 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2004 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Inspeção radiológica para avaliação da integridade estrutural de equipamentos possui uma tradição de mais de 100 anos, e é predominantemente baseada na combinação de uma fonte radioativa e um filme. No decorrer dos anos, filmes especiais têm sido desenvolvidos para realização de ensaios não-destrutivos industriais, os quais permitem inspecionar com alto contraste e resolução espacial. Atualmente, filmes para raios-X industrial são capazes de apontar falhas inferiores a 12 ?m, e podem ser expostos à radiação por um tempo relativamente longo, por exemplo, até atingir a densidade óptica 5 e ainda permanecer na faixa linear. Com o avanço da tecnologia de microeletrônica e do conhecimento sobre o mecanismo de luminescência em cristais, detetores inovativos, denominados de detetores digitais, têm sido desenvolvidos para radiografia industrial, tais tecno logias conhecidas como Imaging Plate e Flat Panel, os quais surgiram na década de 80 e no final de 90, respectivamente. O progresso da tecnologia de detetores digitais tem sido acelerado em função do desenvolvimento da tecnologia de computadores, que têm se tornado mais velozes e mais baratos. A combinação das tecnologias de detetores digitais e computadores permite estabelecer métodos inteligentes de inspeção na indústria. Ademais, esta nova radiologia industrial digital também possibilita novas aplicações, que são inacessíveis com a radiografia tradicional. No capítulo 3, componentes de chumbo de uma bateria automotiva, rejeitada devido a falha elétrica no processo de controle de qualidade da empresa, foram radiografados com um sistema de gamagrafia industrial utilizando uma fonte de Irídio-192 com 1,5Ci de atividade e um detetor digital Imaging Plate. A distância entre a fonte e o filme foi determinada e mantida em torno de 60 cm para obter excelente nitidez e resolução devido ao tamanho da fonte, minimizando assim o fenômeno de penumbra em função dos parâmetros geométricos. Devido à alta sensibilidade do filme Imaging Plate, o tempo de exposição foi de 300s. Como resultado de análise das imagens de radiografia digital, mesmo sem realizar um processamento das imagens, as imagens radiográficas indicam que a causa da falha elétrica deve ser pela alta densidade de bolhas de ar incorporadas no processo de fabricação da bateria, aumentando assim a resistência elétrica da bateria. Ademais, para avaliar qualitativamente as imagens obtidas com uma fonte de alta energia e um detetor de alta sensibilidade Imaging Plate através do sistema de gamagrafia, outros dois componentes distintos da bateria automotiva foram radiografados: isoladores de vidro para linhas de transmissão e uma tubulação de aço com revestimento térmico. Os resultados destes componentes são apresentados e discutidos, com enfoque na técnica de radiografia computadorizada (Imaging Plate). No capítulo 4, é abordada a confecção de uma óptica de raios-X para produção de feixes paralelos utilizando um monocromador assimétrico fabricado a partir de um cristal de quartzo sintético de alta qualidade, facilidades do LNLS/CNPq- Laboratório Nacional de Luz Síncrotron e testes radiográficos digitais com Imaging Plate. O monocromador foi fabricado e testado no Departamento de Engenharia Mecânica da UFPE. Basicamente, o feixe de raios-X na estação experimental XRD-1 do LNLS/CNPq é focalizado com secções da ordem de 1 mm2. A importante função do monocromador assimétrico foi de alargar e produzir um feixe de raios-X altamente paralelo e monocromático, o que elimina o efeito de penumbra, possibilitando obterimagens radiográficas de alta resolução. Em função da energia crítica do anel do LNLS estar em torno de 8 keV, os testes de radiografia no presente trabalho limitaram-se a objetos de baixa absorção. Como resultado, um besouro foi selecionado por possuir uma estrutura interna altamente complexa e radiografado. Detalhes do besouro foram revelados com feixe monocromático, paralelo e utilizando o Imaging Plate. No capítulo 5, são apresentados os resultados iniciais de aplicação de métodos de processamento das imagens digitais sobre as imagens radiográficas industriais digitais obtidas. Foram utilizados softwares comerciais, tais como: VixWin 2000 da empresa Gendex, o Corel Photopaint 10 e o Adobe Photoshop 7. Como resultado, através da utilização de um software de processamento de imagens, pode-se destacar ou realçar aspectos importantes que dificultam a interpretação em imagens originais. Além disto, também é possível extrair informações sob o aspecto dimensional da amostra radiografada, tais como espessura das paredes de uma tubulação e tamanho de defeitos nos dispositivos ensaiados. Neste trabalho, discutimos a aplicação de gamagrafia industrial digital aliada com o detetor Imaging Plate para avaliar o interior dos isoladores de vidro íntegro e quebrado de linhas de transmissão de alta tensão, componentes de bateria e tubulações com defeitos internos. Ademais, imagens digitais obtidas com um feixe paralelo de raios-X de radiação síncrotron possibilitam obter imagens radiográficas de excelente qualidade e em fração de minutos. O detetor Imaging Plate (IP), embora ainda não apresente a resolução comparável a um filme de raios-X industrial de alta resolução, mas apresentam muitas vantagens, tais como: sua maior linearidade de resposta devido a maior faixa dinâmica, maior sensibilidade permitindo a utilização de fontes de menor atividade, o fato de serem reutilizáveis e o envio das imagens digitalizadas por meio de network. Os resultados apresentados no presente trabalho de mestrado mostram que imagens radiográficas industriais de excelente qualidade de componentes industriais podem ser obtidas com o Imaging Plate, mesmo utilizando uma fonte de radiação convencional e de baixíssima atividade
196

A study in short-sight in public elementary schools

Bywater, E. F. W. January 1913 (has links)
Since Cohn’s investigation of the cause a of short-sight and the striking evidence which he brought forward as to the part which Education played in connection therewith, we have been accustomed to regard the schools as the "hot bed" of myopia. In view of the apparently conclusive nature of the statistics obtained by Cohn after an examination of over 10,000 scholars in German Schools, supplemented, as these have been, by the work of Snellen, Priestley Smith, Straub (Amsterdam) and many other eminent ophthalmologists, one reads with something of surprise the memoir or Pearson and Barrington “ A First Study of the Inheritance of Vision, and of the relative influence of Heredity and Environment on Sight “. In this memoir, which was issued in 1909 under the auspice of the Eugenic Laboratory of London University, the authors have carefully analysed, by modern statistical methods, much of the evidence adduced in support, of the generally accepted theory that short-sight is largely the result of Educational Environment.
197

Exploiting mTOR cellular signalling to promote retinal ganglion cell survival and axon regeneration after traumatic optic neuropathy

Morgan-Warren, Peter John January 2016 (has links)
Retinal ganglion cell (RGC) apoptosis and failure of optic nerve (ON) axon regeneration contribute to profound visual loss after traumatic optic neuropathy (TON), for which clinically effective treatments are lacking. Experimental manipulations of cellular signalling have identified phosphoinositide-3-kinase (PI3K) and its downstream mediators mTOR and GSK3\(\beta\) as important regulators of neuronal survival and axon regeneration in an animal model of TON, using targeted siRNA to knock-down key negative regulators of cellular signalling, and to investigate underlying mechanisms using retinal cultures. Intravitreal treatment with siRNA targeting RTP801, a stress-induced inhibitor of mTOR, promoted RGC survival and axon elongation after ON crush (ONC), and potentiated reactive gliosis. In vitro, siRTP801- induced neuroprotection was direct, but required GFAP\(^+\) activated retinal glia to stimulate neurite elongation. siRTP801 also potentiated levels of glial-derived Trk-dependent neurotrophic factors. Knock-down of the axon growth cone/apoptosis regulator GSK3\(\beta\) was also neuroprotective, promoted modest axon elongation after ONC, and increased neurite sprouting in vitro. GSK3\(\beta\) suppression counteracted neurite growth-inhibition induced by CNS myelin-derived Nogo. Combined treatment with siRTP801/siGSK3\(\beta\) augmented axon regeneration after ONC. These findings support a clinically translatable siRNA approach targeting PI3K/mTOR signalling as the basis for development of novel neuroprotective/axogenic therapies.
198

Restlessness of meaning: an exploration of how visual artists are working with museum collections

Darbyshire, Jo January 2003 (has links)
This exegesis is an exploration of issues involved in making an exhibition -The Gay Museum (2003) -at the Western Australian Museum. Inspired by the work of artist Joseph Kosuth at the Brooklyn Museum (1990) and curator Peter Emmett at the Museum of Sydney (1994), this project attempts to explore and extend the role of artists as curators in contemporary museums. The project also shows that by re- interpreting objects in museum collections artists can actively challenge and support museums in a period of change and that collaboration between artists and museums as 'makers of meaning' can open up new possibilities for both. The curatorial vision for the exhibition therefore included strategies from contemporary museums - a multi-disciplinary approach and the use of non-linear narrative - and strategies from the contemporary art world -those that explore an aesthetic approach to objects and installation. Research for the project was determined by the expectations, unique histories and political choices that shaped and connected three 'communities' - Jo Darbyshire from the visual arts community, the Western Australian Museum community and the gay and lesbian community of Western Australia. As The Gay Museum project shows, the collaboration between artists and museums can contribute to museums being sites that vibrantly reflect contemporary cultural changes.
199

The ontological evaluation of the requirements model when shifting from a traditional to a component-based paradigm in information systems re-engineering

Valverde, Raul January 2008 (has links)
[Abstract]: The vast majority of present legacy information systems were implemented using the traditional paradigm. The traditional paradigm consists of modeling techniques used by system analysts such as System Flow Charts and Data Flow Diagrams (DFD) to capture, during the analysis phase, the activities within a system.However, with recent developments, particularly trends towards e-Commerce applications, platform independence, reusability of pre-built components, capacity for reconfiguration and higher reliability, many organizations are realizing they will need to re-engineer their systems into new component based systems that meet thesetrends given the limitations of legacy systems to adapt to these new technical requirements.There is a high degree of interest and concern in establishing whether or not a full migration to a more portable and scalable component-based architecture will be able to represent the legacy business requirements in the underlying requirements model of the re-engineered information systems.As a result, this study poses the question: Is the resulting component-based requirements model ontological equivalent to the legacy requirements model whenshifting paradigms in the re-engineering process?After a literature review, the research study is justified given the differences in requirements modeling between component-based and traditional paradigms, whichgive an indication that the resulting component model might not represent the same business requirements represented in the legacy system requirements model.The study evaluated the requirements models generated by the component-based and traditional approaches when shifting paradigms in the re-engineering process inorder to verify that the re-engineered component-based requirements model was capable of representing the same business requirements of the legacy system. Design science and an ontological evaluation using the Bunge-Wand-Weber(BWW) model were the central research methodologies for this study.A legacy system was selected as part of the case study and re-engineered by using the component-based paradigm with the help of UML diagrams. The requirements model of the legacy system was recovered using reverse engineering and compared to the component-based requirements model using normalized reference models generated with the help of BWW transformation maps. These maps revealed that there-engineered requirements models were capable of representing the same business requirements of the legacy system. A set of rules was suggested when reengineeringlegacy into component-based information systems to ensure the same representation of legacy system’s requirements in the re-engineered requirements model.Finally, this research included directions of future research that put emphasis on the development of automated software tools for systems re-engineering that couldimplement the rules suggested in this study and the ontological methodology approach used.
200

How People Re-find Information When the Web Changes

Teevan, Jaime 18 June 2004 (has links)
This paper investigates how people return to information in a dynamic information environment. For example, a person might want to return to Web content via a link encountered earlier on a Web page, only to learn that the link has since been removed. Changes can benefit users by providing new information, but they hinder returning to previously viewed information. The observational study presented here analyzed instances, collected via a Web search, where people expressed difficulty re-finding information because of changes to the information or its environment. A number of interesting observations arose from this analysis, including that the path originally taken to get to the information target appeared important in its re-retrieval, whereas, surprisingly, the temporal aspects of when the information was seen before were not. While people expressed frustration when problems arose, an explanation of why the change had occurred was often sufficient to allay that frustration, even in the absence of a solution. The implications of these observations for systems that support re-finding in dynamic environments are discussed.

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