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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.
541

A fotografia sem câmera : revelações de especificidades da fotografia através do quimigrama

Gonçalves, Myra Adam de Oliveira January 2007 (has links)
Esta dissertação foca um processo de criação de imagens fotográficas a partir de manipulações químicas feitas sobre superfícies fotossensíveis, diretamente sobre o papel ou negativo, sem utilizar para isso o aparato tecnológico – a câmera. A partir dessa abordagem, a dissertação analisa os limites daquilo que conhecemos como fotografia. A pesquisa convergiu para a investigação das possibilidades fotográficas inerentes às superfícies sensíveis e fotossensíveis, às soluções fotoquímicas e para o cruzamento dessas possibilidades fotográficas com outras linguagens artísticas. O trabalho confrontou a fotografia com suas especificidades e buscou desvendar os domínios da fotograficidade, que se configurou como um lugar apropriado para vasculhar as certezas e incertezas do que é a fotografia. As reflexões teóricas foram instituídas pelo trabalho plástico. / This dissertation aims at a photographic images creation process from chemistry manipulations made over light sensitive surfaces, directly on the paper or negative, without the camera. From this point of view the dissertation analyses the limits of which we know as photograph. The research converged to an investigation of the inherent photographic possibilities to sensitive and light sensitive surfaces, to photochemical solutions and to an approaching of these photographic possibilities to other kinds of artistic languages. The creation process faced photograph and its unique features and, by dealing with them, tried to reveal the photographs unique characteristics, which showed a specific place to search the certainties and uncertainties of what photography is. The theoretic reflections were established by the artistic work.
542

SICOM: Um conceito de sistema de controle de manobras sensível a contexto aplicado ao setor de energia elétrica

ARAÚJO, Julierme Silva de 12 September 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-03-31T15:37:57Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertacao Julierme Araujo _ Versão Final_Biblioteca Central.pdf: 5689636 bytes, checksum: 17f1c9468e867914d378e2fef1626269 (MD5) / Made available in DSpace on 2016-03-31T15:37:57Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertacao Julierme Araujo _ Versão Final_Biblioteca Central.pdf: 5689636 bytes, checksum: 17f1c9468e867914d378e2fef1626269 (MD5) Previous issue date: 2014-09-12 / Vários fatores interligados ou isolados podem desencadear graves anormalidades no Sistema Elétrico de Potência (SEP). Dentre estes fatores, um de fundamental importância é o humano. Os operadores (OP) são aqueles que estão constantemente em contato com os equipamentos das instalações (presencialmente ou remotamente) e desempenham papel vital na correta operação do SEP. Um das principais atividades do OP é a execução de manobras em tempo real, seguindo o estabelecido pelo documento de plano de manobras (PM). No entanto, devido à natureza repetitiva destas atividades os OPs estão sujeitos a cometerem falhas operacionais. Tais eventos podem ocorrer através de uma mera desatenção na execução dos PMs ou na total negligência destes. Operações em equipamentos a partir de manobras mal elaboradas, bem como softwares que não favoreçam a elaboração e a validação de tais manobras, também são fatores que promovem a ocorrência de falhas humanas e anormalidades no processo. Neste trabalho é apresentada uma arquitetura para implementação de um conceito de sistema baseado em software, hardware e sensibilidade a contexto. Em simulações referentes às operações sobre manobras, foi possível observar o sistema atuando de forma preventiva ao alertar o usuário sobre possíveis atividades inconsistentes. A execução de manobras em subestações ocorreu através de uma versão do sistema para dispositivos móveis. Essa abordagem promoveu vários benefícios como, por exemplo, a eliminação de falhas oriundas de atividades repetitivas, o estabelecimento de um mecanismo de confirmação da execução da manobra e o aperfeiçoamento do processo de interação entre os operadores de sistemas e operadores de subestações. Tendo como referência resultados que apontam uma redução de 47% da taxa de anormalidades geradas pelos processos de elaboração e validação de manobras operativas, chegou-se a conclusão que o conceito de sistema apresentado neste trabalho promoveu uma considerável diminuição nas deficiências oriundas desses processos e aumentou a qualidade e a segurança no processo de execução de manobras. / Several factors, interconnected or isolated, may be the cause of abnormalities on the Electric Power Systems (EPS). Among such factors, human factors play a fundamental role. Operators (OPs) are the staff responsible to deal with installations equipment, operated both presently or remotely, playing a vital part to the correct operation of the EPS. One of OP’s main activities is executing maneuvers in real time, following what was established by the maneuvers plan (MP) establishes. However, due to the repetitive nature of these activities, OPs are subject to commit operational failures. These events may occur through a mere inattention in the execution of the MPs or in their total neglect. Equipment operations from poorly elaborated maneuvers, as well as softwares that do not favor the elaboration and validation of those maneuvers are also factors that promote the occurrence of human failure and abnormalities in the process. Herein this work we present a hardware - software architecture sensible to context. In simulations related to operations on maneuvers it was possible to observe the system’s prototype acting preventively when it alerts the user about possible inconsistent activities. The maneuvering in substations occurred through a system version for mobile devices. This approach promoted several benefits such as the correction of the faults originated from repetitive activities, the establishment of a mechanism for confirmation of the maneuvering and the improvement of the interaction process between system and substation operators. Having as reference results which show a reduction of 47% in the rate of abnormalities generated by the drafting and validation of operational maneuvers, we concluded that the concept of system presented in this paper promoted a considerable decrease in deficiencies originated from these processes and increased the quality and safety maneuvers in the process.
543

Uma análise dos fatores associados às taxas de internações por causas sensíveis à atenção básica, nos municípios pernambucanos, de 2008 a 2013

Souza, Bruna Maria Bezerra de 31 October 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-06-14T12:21:29Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) BRUNA MARIA BEZERRA DE SOUZA.pdf: 2121228 bytes, checksum: 32caa8f0b58418989f6fde2b282e8d0e (MD5) / Made available in DSpace on 2016-06-14T12:21:29Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) BRUNA MARIA BEZERRA DE SOUZA.pdf: 2121228 bytes, checksum: 32caa8f0b58418989f6fde2b282e8d0e (MD5) Previous issue date: 2014-10-31 / A pesquisa foi desenvolvida com o objetivo de analisar os fatores associados às taxas de internações hospitalares por condições sensíveis à atenção básica (ICSAB), nos municípios pernambucanos, entre o período de 2008 a 2013. Trata-se de uma avaliação empírica que foi desenvolvida com dados secundários, sob o enfoque quantitativo, tendo como unidades de análise os municípios que integram o Estado de Pernambuco. Foram utilizados os modelos Mínimos Quadrados Ordinários (MQO) e efeitos fixos aplicados sob os dados organizados em painel. Como variáveis explicativas foram utilizados: número de equipes de saúde da família (ESF) implantadas, cobertura da atenção básica, valores gastos com as internações por causas sensíveis e repasse federal para a atenção básica. A análise descritiva demonstrou que houve diminuição das internações por causas sensíveis à atenção básica por 1.000 habitantes, nos municípios pernambucanos de 2.064 em 2008 para 1.869 em 2013, isto é, uma queda de 9,42%. Sendo a redução das internações gerais de 3,43%. Tal fato, reflete o momento histórico vivenciado pelo SUS, considerando que os municípios têm fortalecido sua cobertura da atenção básica, investindo mais nas ações de atenção à saúde propostas pela Estratégia de Saúde da Família. Através dos modelos MQO e efeitos fixos, concluímos que os gastos com as internações por causas sensíveis à atenção básica, o repasse Federal para este nível de atenção e o número de ESF foram as variáveis que se mostraram estatisticamente significativas, apresentando coeficientes negativos para nº de ESF e repasse Federal, e positivo para os gastos com as ICSAB. De maneira geral, este estudo aponta a necessidade de fortalecer, ainda mais, a atenção primária para que a mesma assuma a coordenação de uma rede de atenção à saúde que favoreça melhor qualidade e maior resolutividade de suas ações. E ainda, fornece subsídios para que gestores possam refletir sobre os problemas de saúde local, propondo políticas de saúde mais efetivas com o objetivo de diminuir cada vez mais as internações por causas sensíveis à atenção básica. / This study aimed to analyze the factors associated with rates of hospital admissions for primary care sensitive conditions (ICSAB) in the municipalities of Pernambuco, between the period 2008 to 2013. It is an empirical evaluation that was developed based on secondary data, according quantitative approach, taking as units of analysis the municipalities of the state of Pernambuco. OLS models (OLS) and fixed effects applied in the data organized in the panel were used. Explanatory variables as: number of family health teams (FHT) implemented, coverage of basic health care, amounts spent with hospitalizations for sensitive causes, federal funding for primary care. The descriptive analysis showed that there were fewer hospitalizations for sensitive primary care per 1,000 population causes in Pernambuco towns of 2,064 in 2008 to 1,869 in 2013, a decrease of 9.42%. Being the reduction of overall hospitalizations of 3.43%. This fact reflects the historical moment experienced by SUS, considering that municipalities have strengthened their coverage of basic health care, investing more in health care actions proposed by the Family Health Strategy. Through OLS and fixed effects models we conclude that spending on hospitalizations for primary care sensitive causes, the federal transfer to this level of attention and the number of FHS were the variables that were statistically significant, with negative coefficients for number of FHS Federal and transfer, and positive for spending on ICSAB. Overall, this study highlights the need to strengthen further, primary care so that it takes the coordination of a network of health care which fosters better quality and better resolution of their actions. And also provides subsidies for managers to reflect on local health issues, proposing more effective health policies aiming to increasingly reduce hospitalizations for primary care sensitive causes.
544

Classificação de espécies arbóreas em função da tolerância ao alagamento e preparo de solo para restauração de florestas paludosas / Tree species classification based on flooding tolerance and soil preparation for the restoration of wetlands

Mariana Luzia Bettinardi 22 April 2014 (has links)
A água é um bem necessário a toda a humanidade, à agricultura e às indústrias. É o bem mais escasso atualmente e será muito mais nos próximos anos. A proteção dos recursos hídricos para garantia do bem-estar da humanidade torna-se essencial e com isto a restauração florestal de nascentes e áreas ciliares é alvo de projetos em todo o mundo. As áreas hidrologicamente sensíveis (AHS) dentro da bacia hidrográfica são as porções mais importantes neste contexto, no entanto, devido à saturação hídrica do solo ocasionada pela dinâmica do lençol freático, a sua recuperação é dificultada desestimulando pesquisas e ações de restauração. Diante desta lacuna, este estudo teve o objetivo de buscar estratégias para a restauração florestal de AHS. Para isso foi testado em viveiro a tolerância a diferentes níveis de saturação hídrica de 15 espécies típicas de ambientes alagados e uma espécie não típica como controle. As espécies foram avaliadas quanto ao crescimento em altura, diâmetro à altura do solo, sobrevivência, desenvolvimento de respostas morfológicas e possível associação destas com as taxas de crescimento. Foi feita uma análise de agrupamento que classificou e agrupou as espécies de acordo com cinco níveis de tolerância ao alagamento, identificando que para a maioria das espécies quanto maior o nível de saturação hídrica menor é a tolerância a este estresse. A análise de variância e o teste de Tukey identificaram quais espécies apresentaram características morfológicas (hipertrofia de lenticelas e raízes adventícias) e os indicadores morfológicos foram comparados nos grupos constituídos da análise de agrupamento que revelou que estas respostas estão associadas à adaptação quanto ao crescimento e sobrevivência das espécies. Dois experimentos em campo também foram realizados visando testar métodos de preparo de solo que mais favorecessem o estabelecimento e o crescimento inicial das espécies. Foi feita uma análise de variância e teste de Tukey para testar se o método de preparo de solo tem efeito sobre o crescimento em altura e diâmetro e o tempo de sobrevivência para as espécies e uma análise de agrupamento para definir grupos de espécies com características funcionais que favoreçam os projetos de restauração. Verificou-se que os métodos de preparo de solo não foram determinantes para o estabelecimento e desenvolvimento das espécies típicas de AHS em pequenas escalas e que a escolha das espécies mais tolerantes à saturação hídrica em diferentes níveis é o fator mais importante na restauração desses ambientes. Desta forma, em projetos de restauração de florestas brejosas, a seleção de espécies adaptadas a estas condições é mais importante do que os métodos de preparo do solo, e futuros estudos deveriam focar em identificar grupos funcionais de espécies que possam ser usadas nestes projetos. / From agriculture to the industry, water is an essential resource for humanity. It is also the scarcest resource at the present time and it will be scarcer in the next years. The protection of water resources is of most importance to ensure humanity\'s well-being. Thus, projects aiming at the restoration of springs and riparian forests are being carried out around the world. In this context, hydrologically sensitive areas (HSA) of the river basins are the most important sites for water resources provision. However, water table dynamics causes water saturation of the soil in these areas, imposing barriers to recuperation and discouraging restoration practice and research. In this context, this study aims to analyze strategies for the ecological restoration of HSA. We carried out nursery tests to assess the hydrological saturation tolerance of 15 tree species typical from wetlands and used a non-typical species as control. Species were evaluated based on height and diameter at soil height increase, survival, development of morphological responses and the possible relation of the latter with growth rates. The cluster analysis classified species in groups based on five hydrological saturation tolerance levels, pointing that, for most species, higher hydrological saturation levels results in lower tolerance to this stress. An analysis of variance and Tukey test identified which species presented morphological characteristics (lenticels hypertrophy and adventitious roots) and the morphological indicators were compared among the clustered groups; this analysis demonstrated that such morphological responses are associated to the species adaptation for both survival and growth in saturated conditions. Two field experiments were also carried out aiming to test soil preparation that could favor seedling establishment and growth. An analysis of variance and Tukey test was carried out to test the effects of soil preparation on seedling height and diameter at soil height growth and survival. Additionally, we carried out a cluster analysis to separate species into groups containing functional characteristics that may favor restoration projects. We observed that soil preparation techniques, in small scale, had no influence on the establishment and development of seedlings typical of HSA and that the selection of species that are tolerant to hydrological saturation at different levels is the most important factor for restoration of these environments. Thus, restoration projects in wetlands should give special attention for the selection of species adapted to these conditions, which is more determinant for restoration success than soil preparation. Future studies should focus in identifying species functional groups that could be used to restore these areas.
545

Detector de raios-X sensível à posição. / X-rays detector sensitive to the position.

Eduardo Luiz Augusto Macchione 04 December 1990 (has links)
Um contador a gás, com multifios, sensível à posição, para a detecção de raios X foi construído utilizando linhas de atraso integradas para leitura da posição. Seis linhas de atraso (50ns de atraso cada, frequência de corte de 40MHz) cobrem um comprimento sensível total de 150mm, possuindo uma razão do atraso total pelo tempo de subida dos sinais na linha adequadas para a detecção em posição raios X de 5,9keV do ANTIPOT. 55 Fe com alta resolução. Testes usando a forneceram uma não-linearidade linha de integral máxima menor que 0,1% e não-linearidade diferencial máxima de ±4,0%, com o detector utilizando a mistura 700torr. Testes similares foram feitos usando de Ar-CH IND 4 (90%-10%) a a linha de 8,04keV de um tubo de raios X de Cu. Uma resolução total de 330m, e as mesmas não-linearidades integral e diferencial foram obtidas. Com a finalidade de t.est.ar o comportamento do detector sob condições experimentais reais, duas diferentes amostras foram analisadas na região de espalhamento em baixo ângulo. As amostras analisadas foram o carvão vítreo e o dodecil sulfato de sódio (SLS). O feixe de raios X foi colimado por um conjunto de fendas, com 50,um cada uma delas e separadas de 98mm. A distância entre a amostra e o detector era de 404,5mm, fazendo com que a região sensível do detector cobrisse um ângulo de espalhamento de ±12 °. Foram obtidos um raio de giro de 22 Å para o carvão vítreo e um dos parâmetros da rede cristalina c de 39,1 Å para o SLS. Estes resultados estão de acordo com trabalhos anteriores obtidos com técnicas tradicionais de maior dispêndio de tempo que utilizam detectores de Nal(T1) e chapas fotográficas em uma câmara de Laue. / A multiware position sensitive gas counter for X-Ray detection was developed in our laboratory making use or commercial delay-lines for position sensing. Six delay-line chips (50ns delay each 40Mhz cut-off frequency) cover a total sensitive length of 190mm leading to a delay-risetime ratio that allows for a high-resolution position detection. Tests using the 5,9keV X-Ray line from a 55Fe source an integral linearity better than 0,1% and a maximum differential linearity or ±4,0% were obtained operating the detector with an Ar-CH 4 (90%-10%) gas mixture at 700torr. Similar tests were performed using the 8,04keV line from a Cu X-Ray tube. A total resolution or 330m, and the same integral and differential linearities were obtained. In order to check the detector performance under usual experimental conditions two different samples were analyzed in the low scattering-angle region. The samples analyzed were vitreous carbon and sodium dodecyl sulfate (SLS). The X-Rays were collimated by a set or slits each 50m wide separated by 98mm. The distance between the sample and the detector was 404,5mm, so that the detector covered a scattering angle of ±12°. A radius of gyration of 22Å for vitreous carbon and a crystallographic parameter of 39,1Å for SLS were obtained. These values are in good agreement with those obtained with the more time-consuming traditional techniques making use of a rotating NaI(T1) detector and photographic plates with a Laue camera.
546

Hantering av den personliga integriteten inom e-handel : Enkätundersökning för registrerade användare på sidan tradera. Värden inom den personliga integriteten tas fram och andra viktiga faktorer för ett e-handelsföretag / Handling the concept of privacy in e-commerce

Ternström, Robert January 2012 (has links)
Allt fler företag väljer att vara webbaserade och ägna sig helt till e-handel. Samtidigt fortsätter antalet e-handelsföretag att öka i antal kraftigt. Företagens behov av personlig information och kunddata har även ökat för att förbli konkurrenskraftiga. Vilket skapar ett problem, behovet av denna personliga information hos företagen riskerar att inkräkta på användarens personliga integritet. Tidigare forskning presenterar inte mycket angående värdet av den personliga integriteten och de fördelar ett skyddande av detta genererar.  En empirisk studie bland svenska användare på e-handelssidan tradera där deltagarna delade deras åsikter och värden angående den personliga integriteten och e-handel utfördes och sammanställdes. Den personliga integriteten ses som ett värde för att utreda detta begrepp med en konceptuell utredning, som är en teori inom värdekänslig design. Bidraget till forskningen är ett ramverk för e-handelsföretag som handlar om hur de skall hantera den personliga integriteten. Arbetet har präglats mycket av inläsning som det har getts utrymme för inom rapporten. / More and more companies choose to be online and devote themselves entirely to e-commerce. The number of companies who choose to be online is still continuing to increase rapidly.  The companies needs for personal information and customer data has increased in order to remain competitive. The problem is that the needs for this personal information from the companies are threating to intrude the customers privacy. Previous research is not addressing the value of information privacy and the benefit of privacy protection. I have conducted an empirical survey study among Swedish users on the e-commerce site Tradera where the participants shared their beliefs and values regarding privacy and e-commerce. I choose to see the privacy as a value in order to investigate this concept in a conceptual study, which is a theory in value sensitive design. My contribution to the research will be a framework for e-commerce and how they should manage the concept of privacy in e-commerce.
547

Apprentissage actif en-ligne d'un classifieur évolutif, application à la reconnaissance de commandes gestuelles / Online active learning of an evolving classifier, application to gesture command recognition

Bouillon, Manuel 18 March 2016 (has links)
L'utilisation de commandes gestuelles est une nouvelle méthode d'interaction sur interface tactile. Une bonne méthode pour faciliter la mémorisation de ces commandes gestuelles est de laisser l'utilisateur les personnaliser. Ce contexte applicatif induit une situation d'apprentissage croisé, où l'utilisateur doit mémoriser le jeu de symboles elle système doit apprendre à reconnaître les différents symboles. Cela implique un certain nombre de contraintes, à la fois sur le système de reconnaissance de symboles ct sur le système de supervision de son apprentissage. Il faut par exemple que le classifieur puisse apprendre à partir de peu de données, continuer à apprendre pendant son utilisation et suivre toute évolution des données indéfiniment. Le superviseur doit quant à lui optimiser la coopération entre l'utilisateur et le système de reconnaissance pour minimiser les interactions tout en maximisant l'apprentissage. Cette thèse présente d'une part, le système d'apprentissage évolutif Evolve oo, capable d'apprendre rapidement il partir de peu de données et de suivre les changements de concepts. D'autre part, elle introduit le superviseur actif en-ligne lntuiSup qui permet d'optimiser la coopération entre le système et l'utilisateur, lors de l'utilisation de commandes gestuelles personnalisées notamment Evolve oo est un système d'inférence floue, capable d'apprendre rapidement grâce aux capacités génératrices des prémisses des règles, tout en permettant d'obtenir une précision élevée grâce aux capacités discriminantes des conclusions d'ordre un. L'intégration d'oubli dans le processus d'apprentissage permet de maintenir le gain de l'apprentissage indéfiniment, permettant ainsi l'ajout de classes à n'importe quel moment de l'utilisation du système ct garantissant son évolutivité « à vie». Le superviseur actif en-ligne lntuiSup permet d'optimiser les interactions avec l'utilisateur pour entraîner un système d'apprentissage lorsque l'utilisateur est dans la boucle. Il permet de faire évoluer la proportion de données que l'utilisateur doit étiqueter en fonction de la difficulté du problème et de l'évolution de l'environnement (changements de concepts). L'utilisation d'une méthode de« dopage» de l'apprentissage permet d'optimiser la répartition de ces interactions avec l'utilisateur pour maximiser leur impact sur l'apprentissage. / Using gesture commands is a new way of interacting with touch sensitive interfaces. In order to facilitate user memorization of several commands, it is essential to let the user customize the gestures. This applicative context gives rise to a crosslearning situation, where the user has to memorize the set of commands and the system has to learn and recognize the different gestures. This situation implies several requirements, from the recognizer and from the system that supervizes its learning process. For instance, the recognizer has to be able to learn from few data samples, to keep learning during its use and to follow indefinitely any change of the data now. The supervisor has to optimize the cooperation between the recognizer and the system to minimize user interactions while maximizing recognizer learning. This thesis presents on the one hand the evolving recognition system Evolve oo, that is capable of fast teaming from few data samples, and that follows concept drifts. On the other hand, this thesis also presents the on line active supervisor lntuiSup, that optimizes user-system cooperation when the user is in the training loop, as during customized gesture command use for instance. The evolving classifier Evolve oo is a fuzzy inference system that is fast learning thanks to the generative capacity of rule premises, and at the same time giving high precision thanks to the discriminative capacity of first order rule conclusion. The use of forgetting in the learning process allows to maintain the learning gain indefinitely, enabling class adding at any stage of system learning, and guaranteeing lifelong evolving capacity. The on line active supervisor IntuiSup optimizes user interactions to train a classifier when the user is in the training loop. The proportion of data that is labeled by the user evolves to adapt to problem difficulty and to follow environment evolution (concept drift s). The use of a boosting method optimizes the timing of user interactions to maximize their impact on classifier learning process.
548

QUANTIFYING THE EFFECTS OF HYDROSTATIC PRESSURE ON FIBROBLAST GROWTH FACTOR-2 BINDING BY THE HUMAN ENDOTHELIUM

McKenty, Taylor R. 01 January 2017 (has links)
Fluid pressures regulate endothelial cell (EC) tubulogenic activity involving fibroblast growth factor 2 (FGF-2) and its receptor, FGF receptor 2 (FGFR2). Our lab has recently shown that sustained 20 mmHg hydrostatic pressure (HP) upregulates EC sprout formation in a FGF2-dependent fashion. This upregulation of sprout formation may be due to enhanced FGF-2 / FGFR2 interactions in the presence of 20 mmHg HP. We hypothesize that exposure of ECs to 20 mmHg sustained HP enhances FGF-2 binding kinetics. We used a custom hydrostatic pressure system, immunofluorescence, and FACS to quantify FGF-2 binding by ECs in the absence or presence of a range of HPs for 30 minutes. Relative to cells maintained under control pressure, ECs exposed to 20, but neither 5 nor 40 mmHg, displayed a significant increase in binding affinity to FGF-2. EC binding of VEGF-A, another angiogenic growth factor, was unaffected by similar pressure stimuli. Additional studies showed that pressure-selective FGF-2 binding was independent of FGFR2 surface expression. These results implicate the FGF-2 axis in the pressure-sensitive, magnitude-dependent angiogenic processes which we have previously described. The present study provides novel insight regarding the involvement of FGF-2 signaling and interstitial pressure changes in various microvascular physiological and pathobiological processes.
549

Integrating Climate Sensitive Design Principles in Municipal Processes : A Case Study of Edmonton’s Winter Patios

Sanborn, Emma January 2017 (has links)
This paper explores winter patios in Edmonton through the lens of place and climate sensitive design, then reflects upon the existing regulations that influence the design and management of winter patios in Edmonton. The City of Edmonton provides this research opportunity because it is currently pursuing the creation of a four-season patio culture in the city, and has created a strong WinterCity agenda. The introduction explores Edmonton’s local climate and its winter city strategy. This is followed by an explanation of the study’s methodology. The purpose of this thesis is to study how climate sensitive design principles can be applied to create places that attract winter activity. The research questions ask how climate sensitive design principles are currently incorporated in patios, what barriers exist to creating these spaces, and how to overcome these barriers in municipal processes. Many cities in cold climates seek ways to create vibrant, active cities through all seasons, and this study explores how climate sensitive planning principles can help create environments that invite winter activity. To answer the research question, a qualitative methodology was used to examine the case study of Edmonton winter patios using Eliasson’s (2007) concept of place and microclimate. The study identifies design weaknesses in Edmonton patios with little provision of shelter from wind, snow and rain, as well as limited consideration of snow storage and removal. Interviews and document review identify lack of interest and a lack of attention to the physical component of place as barriers to the creation of winter patios. Finally, the use of analytical tools such as urban climatic maps are suggested, as well as the introduction of microclimate standards so information about weather and microclimate can influence how physical components of place are planned and evaluated.
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Cytotoxic lymphocytes in children's cow's milk sensitive enteropathy of delayed type

Augustin, M. (Merja) 10 May 2005 (has links)
Abstract Food hypersensitivities are becoming increasingly common worldwide. Previous studies indicate that cell mediated immunity has a role in delayed paediatric gastrointestinal food hypersensitivities, but the exact pathogenetic mechanisms are unknown. Cytotoxic activation of T-lymphocytes is known to play an important role in the pathogenesis of celiac disease (CD). The pathogenetic mechanisms of cow's milk protein sensitive enteropathy (CMSE) are largely unknown. CMSE is a non-IgE related type of food hypersensitivity with variable gastrointestinal symptoms but no visible mucosal abnormalities on light microscopy. The diagnosis is based on an open or blinded elimination/challenge test, as the endoscopic, histological and laboratory findings are generally non-specific. This thesis aims to characterize the role of lymphocyte cytotoxicity in the pathogenesis and diagnosis of CMSE in preschool and school aged children, including comparison with CD where the pathogenetic significance of cytotoxicity is well established. The study cohort consisted of 151 children, including 57 with untreated CMSE, 18 with treated CMSE, 24 with CD, and 52 controls. Using immunohistochemistry, the mucosal expressions of cytotoxic T cell-restricted intracellular antigen type 1 (TIA-1), perforin, granzyme A and B were analysed in the duodenal bulb and descending duodenum. Intraepithelial T-lymphocytes were labelled with CD3, alpha/beta and gamma/delta T cell receptor antigens. To determine the rates of overall and epithelial apoptosis as well as proliferation, the immunohistochemical TUNEL technique, M30 and Ki-67 antibodies were used. Serum levels of granzymes, CD30 and soluble Fas were studied using ELISA method. The number of intraepithelial lymphocytes with TIA-1, perforin and granzyme A containing granules was increased in CMSE. This increase was related to antigen challenge and not a constitutional abnormality. The cytotoxic reaction in CMSE differed from that in CD by being of lesser magnitude, concerning predominantly the descending duodenum and not showing signs of cytotoxicity related epithelial destruction. The serum levels of GrA, GrB and CD30 were increased in both CMSE and CD, correlating with the number of duodenal CD3+, alpha/beta and gamma/delta+ intraepithelial lymphocytes. The results strongly support the role of cell-mediated immunity in the pathogenesis of CMSE. Mucosal cytotoxic activation seems to be manifested by the release of cytoxicity related proteins in serum. This provides a new approach to the monitoring of intestinal immune activation which could help in diagnosis and in objectively monitored treatment response.

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