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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.
51

A Case of Anomalous Left Anterior Descending Artery Originating From the Right Sinus of Valsalva

Patel, Niravkumar, Bhogal, Sukhdeep, Ramu, Vijay, Helton, Thomas 01 June 2021 (has links)
The anomalous origin of coronary arteries has been extensively documented in the literature. Most of the anomalies are incidentally found either during coronary angiography or imaging studies and are usually benign; however, malignant outcomes have been reported in the literature. Here, we present the case of a 76-year-old male with non-ST segment elevation myocardial infarction who was found to have an asymptomatic anomalous origin left anterior descending artery from the right sinus of Valsalva.
52

Galactose Modified Polyvinylamine, a New Class of Water Soluble Polymers

Mokhtari, Hajir 04 1900 (has links)
<p>Synthetic carbohydrate carrying polymers have gained substantial attention recently due to their biocompatibility and their wide range of applications such as targeted drug delivery systems, gene therapy and cell-specific biomedical materials. The overall objective of this research is to develop novel carbohydrate bearing polymers through modification of polyvinylamine (PVAm) backbone with galactose groups and to discover potential applications for this new category of glycopolymers.</p> <p>PVAm-g-galactose (PVAm-GAL) with various molecular weights and grafting extents were prepared and characterized by nuclear magnetic resonance (NMR) and potentiometric and conductometric titration. Bonding of PVAm-GAL with phenylboronic acid modified PVAm (PVAm-PBA) and phenylboronate modified surfaces were studied on a quartz crystal microbalance with dissipation (QCM-D). Multilayer assembly of alternating layers of PVAm-GAL and PVA-PBA was formed on the silica sensor.</p> <p>Interaction of PVAm-GAL with RCA<sub>120</sub> lectin, a galactose specific protein, was studied on a silica sensor using QCM-D. Galactose binding proteins are overexpressed in hepatocyte and have been widely exploited for targeting the liver tissue with the help of galactosylated polymeric carriers. RCA<sub>120 </sub>lectin shows spontaneous adsorption on galactose rich surfaces obtained by the adsorption of PVAm-GAL on silica sensors. Association constant of the interaction was calculated . Effect of pretreatment with bovine serum albumin (BSA) was also examined.</p> <p>Cationic polymers can form polyelectrolyte complexes (PECs) with negatively charged DNA, resulting in formation of nano-sized complexes for gene delivery purposes. PECs based on PVAm-GAL and different DNA samples were prepared and their physicochemical properties were investigated using dynamic light scattering (DLS) and electrophoretic mobility measurements. Furthermore, PVAm-GAL was studied as coating for Ca-alginate beads which are widely used for cell encapsulation purposes. PVAm-GAL can strengthen the capsule’s surface and increase the physicochemical stability of the beads against chemical degradations. PVAm-GAL coated alginate beads successfully survived treatment with sodium citrate and high ionic strength solutions.</p> / Master of Applied Science (MASc)
53

The evaluation of KwaZulu-Natal's priority agricultural sectors for effective export promotion / Amorie Visser

Visser, Amorie January 2012 (has links)
This study provides the strategies that can be implemented to promote the agricultural sector in KwaZulu-Natal and the theory behind economic development, as well as the importance of trade and export growth. There are restrictions in terms of trade and it is important that these are addressed before making a decision to choose a viable, potential and realistic country to export to. This study is aimed answer the research question if agriculture can be seen as a primary export sector in KwaZulu-Natal. Furthermore, this study includes background on the KwaZulu-Natal Province and mainly focus on the indicators such as GDP, employment, health issues and other indicators that will indicate that this province is of importance in South Africa in terms of the agricultural sector. This study uses SARS data to analyse and calculate the Revealed Comparative Advantage (RCA) of all agricultural products of the province. This is done to identify if there is a comparative advantage in the products studied in this study. The products of KwaZulu-Natal also show that this province’s agriculture can be seen as a primary export sector and that this sector is a major contribution to South Africa’s GDP and development. This study uses the Decision Support Model (DSM) to compare the results from the Revealed Comparative Advantage to identify the products and sectors which have the most export potential in the international market. This study reveals that the agricultural products and industries in KwaZulu-Natal with the highest overall export potential are chocolate and cocoa preps, refined soybean oil, and leather products as the three top performers among agricultural products and have the most export potential in the province. Concluding remarks are based on the findings made throughout the study. / Thesis (MCom (International Trade))--North-West University, Potchefstroom Campus, 2012
54

Estudo sobre a aplicação de agregado reciclado de concreto em construção de pavimentos / Study on application of recycled concrete aggregate in pavement construction

Sousa, Wallace Fioravanti de 21 September 2011 (has links)
A exploração dos recursos naturais e a degradação do meio ambiente têm sido fonte de preocupação no âmbito mundial. A busca por soluções alternativas que não causem ou que diminuam os impactos ambientais tornou-se comum na sociedade. Nesse contexto, a pavimentação vem contribuindo significativamente com soluções alternativas para destinação final de diversos tipos de resíduos, principalmente os oriundos da indústria da construção civil que sempre foi uma das maiores geradoras. Os resíduos da construção e demolição (RCD) podem ser transformados em agregados reciclados de ótima qualidade e podem ser aplicados em diversos serviços de engenharia. Os agregados reciclados, segundo a NBR 15116 (ABNT, 2004), são separados em misto e de concreto (ARC). No Brasil existem poucas pesquisas com o ARC, no entanto, as que existem e as pesquisas internacionais relatam que uma característica marcante do ARC é a cimentação própria. Portanto, o objetivo desta pesquisa é estudar o comportamento mecânico, ao longo do tempo de cura, do agregado reciclado de concreto proveniente da Usina de Reciclagem de São Carlos e de sua mistura com um solo laterítico, a fim de utilizá-los na construção de pavimentos. O estudo envolveu a análise dos resultados de resistência à compressão simples, módulo tangente, módulo de resiliência, deformação permanente e índice de suporte Califórnia (CBR) de corpos-de-prova de ARC e da sua mistura com solo laterítico, moldados em diferentes energias de compactação e ensaiados com tempos de cura variados. Ao final, concluiu-se que o agregado reciclado de concreto (ARC) é uma alternativa para construção de bases de pavimentos, podendo também substituir o agregado natural da mistura solo arenoso laterítico - brita descontínua, muito utilizada nas rodovias do interior de São Paulo. / Natural resources exploitation and the environmental degradation are a worldly problem nowadays. Searching for alternative solutions is something usual in most countries. Pavement systems are now contributing significantly with these alternative solutions by using the waste of construction demolition. This specific kind of waste can turn into mixed recycled aggregate or recycled concrete aggregate. There are just few researches in Brazil about the use of recycled concrete aggregate (RCA), however international researches have shown that this aggregate has a very characteristic and positive mark: self cementation. This research has got the objective of studying the mechanic behavior of the recycled concrete aggregate and its mix with lateritic soil on the construction of base pavements with different analytic basis. The study involved the analysis of the laboratorial tests results of the unconfined compressive strength, tangent modulus, resilient modulus, permanent deformation and California Bearing Ration (CBR) of RCA specimens and its mix with lateritic soil, molded in different compaction energy and tested in different curing times. In conclusion, this kind of recycled aggregate has proved to be a sustainable alternative for the natural aggregate in the construction of many roads in small cities of the State of São Paulo - Brazil.
55

Viabilidade do uso de RCD proveniente da geração dos concretos convencional e de alta resistência através da utilização do jigue como agente do beneficiamento

Cunha, Michel Gustavo Cardoso January 2017 (has links)
O presente trabalho avaliou a viabilidade do uso de Resíduos de Construção e Demolição (RCD) provenientes da geração de dois traços de concretos distintos. Um Concreto Convencional-CC (traço em massa:1:2,94:3,56; a/c:0,61) utilizando cimento CP IV 32 e outro concreto de Alta Resistência-CAR (traço em massa:1:1,11:2; a/c: 0,22; com adição, aditivo e pó xadrez vermelho) utilizando cimento CP V-ARI. Após 28 dias de cura, 3 corpos de prova de cada traço foram submetidos ao ensaio de resistência a compressão axial apresentando em média para CC 21,02 MPa e para CAR 95,09 MPa. Os materiais de ambos os traços foram cominuídos através de um britador de mandíbula ajustado para granulometria menor que 19,1 mm e retido em 4,75 mm. Com isso, foram realizados ensaios de granulometria de cada traço, e misturados em volumes iguais para o beneficiamento do material. Os primeiros ensaios foram realizados no jigue a ar, porém os resultados apresentados foram insatisfatórios. Para o jigue à água ocorreu uma separação visível de 3 estágios (Topo, Meio e Fundo) Utilizando somente as camadas de topo e fundo, os agregados reciclados de concreto (ARC) foram utilizados para confecção de novos concretos. Os resultados apontaram que a aplicação do jigue à água possibilitou um beneficiamento do material para uso como agregado graúdo. Os ensaios de resistência à compressão, os concretos produzidos com a camada de fundo do agregado reciclado superaram os produzidos com agregado natural. Nos ensaios de módulo de elasticidade, os concretos com o agregado natural exibiram resultados melhores do que os reciclados do topo, porém para os concretos produzidos com os agregados do fundo, os módulos se igualaram aos dos concretos com agregado natural. No ensaio de absorção, o concreto reciclado mostrou uma absorção maior que o concreto natural. Para a carbonatação os concretos com agregados reciclados tiveram melhores resultados. As avaliações dos efeitos foram concludentes para o uso do jigue no beneficiamento do agregado reciclado de concreto (ARC). / The present work evaluates the feasibility of using Construction and Demolition Waste (CDW) generated by two different concrete mixes, one being aconventional concrete-CC (mix:mass: 1:2, 94:3, 56, w/c: 0,61) using CP IV 32, and another being a high strength concrete - CAR (mix:mass: 1:1, 11:2, w/c: 0.22), with the addition of additive and red pigment) using cement CP V-ARI. After 28 days of curing, three test specimens of each concrete were submitted to the resistance test, presenting 21.02 MPa on average for CC and 95.09 Mpa for CAR. The materials of both mixes were comminuted by jaw crusher, and sieved to a particle size range of -19.1 mm + 4.75 mm. With this, granulometry, tests of each concrete were performed and the concretes were mixed in equal volumes for the application of the material processing. The first tests were performed by air jig, but the results were found to be unsatisfactory A visible separation of 3 stages (Top, Middle and Bottom) was achieved by use of water jig. Using only the top and bottom layers, Recycled Concrete Aggregates (RCA) was added for the creation of new concrete. The results indicate that the application of the water jig made it possible to improve the material for use as a large aggregate. For the compressive strength tests, the concretes produced with the bottom layer of the recycled aggregate surpassed those produced with natural aggregate. In the modulus of elasticity tests, concretes with the natural aggregate presented better results than those recycled from the top. For the concretes produced with the bottom aggregates, the modules matched that of the concrete with natural aggregate. In the absorption test the recycled concrete showed a higher absorption than the natural concrete. For carbonation the recycled had better results. An evaluation of the results concludes in favor of the use of water jig for the recycling of concrete aggregates (RCA).
56

Atmosphere-ocean Interactions in Swell Dominated Wave Fields

Semedo, Alvaro January 2010 (has links)
Ocean wind waves represent the atmosphere-ocean boundary, playing a central role in the air-sea exchanging processes. Heat, mass and momentum are transferred across this boundary, with waves mediating the exchange of principally the momentum between the winds and the ocean surface. During the generation process waves are called wind sea. When they leave their generation area or outrun their generating wind they are called swell. The wave field can be said to be dominated either by wind sea or swell. Depending on the wave regime the momentum and energy exchanging processes and the degree of coupling between the waves and the wind is different. During the growing process, waves act as a drag on the surface wind and the momentum flux is directed downward. When swell dominates the wave field a reverse momentum flux mechanism occurs triggered by swell waves traveling considerably faster than the surface winds. The momentum transfer is now directed from the waves to the atmosphere, and takes place because swell waves perform work on the atmosphere as part of their attenuation process. This upward momentum transfer has an impact on the lower atmosphere dynamics, and on the overall turbulence structure of the boundary layer. A detailed qualitative climatology of the global wind sea and swell fields from wave reanalysis data, is presented, revealing a very strong swell dominance of the World Ocean. The areas of larger potential impact of swell on the atmosphere, from a climatological point of view, are also studied. A model that reproduces the swell impact on the lower atmosphere dynamics, conceptually based on the energy transfer from the waves to the atmosphere, is presented – a  new parameterization for the wave-induced stress is also proposed. The model results are compared with field observations. A modeling simulation, using a coupled wave-atmosphere model system, is used to study the impact of swell in a regional climate model, by using different formulations on how to introduce the wave state effect in the modeling system. / Gränsen mellan hav och atmosfär beskrivs av vågor, dessa spelar en central roll i utbytesprocesser mellan hav och atmosfär. Värme, massa och rörelsemängd överförs vid ytan och utbytet av rörelsemängd mellan vind och havsyta styrs i stor utsträckning av vågorna. Då vågor skapas kallas de för vinddrivna vågor. När vågorna sedan lämnar området där de genererats eller rör sig fortare än den vind som genererat dem kallas de dyning. Ett vågfält kan sägas vara dominerat av antingen vinddrivna vågor eller dyningsvågor. Beroende på vilken vågregim som råder så är kopplingen mellan vågor och vind olika och därmed också utbytesprocesserna för rörelsemängd och energi. Då vågorna genereras fungerar de som en bromsande kraft för vinden och impulsutbytet är nedåtriktat. När dyning dominerar vågfältet inträffar en mekanism för omvänt impulsutbyte som sätts igång av dyningsvågor som färdas avsevärt snabbare än vinden. Rörelsemängd överförs då från vågorna till atmosfären, eftersom dyningsvågorna utför arbete på atmosfären då de dämpas. Den uppåtriktade transporten av rörelsemängd har en stor effekt på dynamiken och turbulensstrukturen i lägre delen av atmosfären. En detaljerad kvalitativ klimatologi av globala vågfält (vinddrivna och dyning) från återanalysdata presenteras och visar att dyning dominerar vågfältet på världshaven. Områden där man kan förvänta sig störst effekt av dyning på atmosfären har identifierats. En konceptuellt baserad modell som reproducerar effekten av dyning på dynamiken i lägre delen av atmosfären presenteras. Modellen styrs av överföring av energi från vågor till atmosfären. I modellen föreslås även en ny parameterisering för våginducerad kraft på havsytan. Modellresultaten är utvärderade mot fältmätningar. En regional klimatmodell, med ett kopplat våg-atmosfärssystem, har använts för att studera den långtida effekten av dyning vid klimatsimulering. Olika formuleringar för beskrivningen av vågornas effekt på atmosfären har använts, beroende på om vinddrivna vågor eller dyning dominerar vågfältet.
57

ARCHITECTURE ET SIMULATION LOCALES DU SYSTEME D'INFORMATION DOMOTIQUE-SANTE INTEGRE A DOMICILE (SID²) POUR LA DETECTION DE SITUATIONS A RISQUE ET L'AIDE A LA DECISION

Virone, Gilles 26 November 2003 (has links) (PDF)
Après un tour du monde des Habitats Intelligents pour la Santé (HIS), nous décrivons la mise en place du système grenoblois développé au laboratoire TIMC : le Système d'Information Domotique-Santé Intégré à Domicile (SID²). Nous faisons l'hypothèse que les rythmes biologiques et sociaux sont liés au comportement, et donc à l'activité physique, que nous mesurons par le déplacement du sujet d'observation au sein de l'habitat. Nous créons le terme " Rythmes Circadiens d'Activité " (RCA) pour faire référence à la mesure comportementale de l'activité des patients dans l'habitat. Le système SID² est composé d'un HIS externe relié à Internet, et d'un HIS local, objet de ce document. L'HIS local effectue la surveillance multi-paramétrique et auto-apprend les habitudes de vie d'un patient à domicile à travers le calcul des RCA, de façon à détecter une évolution anormale de son comportement sur le long terme. Un simulateur a été développé pour valider le système.
58

The evaluation of KwaZulu-Natal's priority agricultural sectors for effective export promotion / Amorie Visser

Visser, Amorie January 2012 (has links)
This study provides the strategies that can be implemented to promote the agricultural sector in KwaZulu-Natal and the theory behind economic development, as well as the importance of trade and export growth. There are restrictions in terms of trade and it is important that these are addressed before making a decision to choose a viable, potential and realistic country to export to. This study is aimed answer the research question if agriculture can be seen as a primary export sector in KwaZulu-Natal. Furthermore, this study includes background on the KwaZulu-Natal Province and mainly focus on the indicators such as GDP, employment, health issues and other indicators that will indicate that this province is of importance in South Africa in terms of the agricultural sector. This study uses SARS data to analyse and calculate the Revealed Comparative Advantage (RCA) of all agricultural products of the province. This is done to identify if there is a comparative advantage in the products studied in this study. The products of KwaZulu-Natal also show that this province’s agriculture can be seen as a primary export sector and that this sector is a major contribution to South Africa’s GDP and development. This study uses the Decision Support Model (DSM) to compare the results from the Revealed Comparative Advantage to identify the products and sectors which have the most export potential in the international market. This study reveals that the agricultural products and industries in KwaZulu-Natal with the highest overall export potential are chocolate and cocoa preps, refined soybean oil, and leather products as the three top performers among agricultural products and have the most export potential in the province. Concluding remarks are based on the findings made throughout the study. / Thesis (MCom (International Trade))--North-West University, Potchefstroom Campus, 2012
59

Le traitement de l'oubli : épreuve de l'incorporation des antirétroviraux et temporalités des traitements du sida en Centrafrique.

David, Pierre-Marie 04 1900 (has links)
Cette thèse propose une description ethnographique et une analyse sociologique de l’arrivée des traitements antirétroviraux (ARV) à Bangui, c’est-à-dire de cette rencontre singulière entre un programme international à l’ampleur inédite et une société locale durement touchée par l’infection. S’appuyant sur trois années de terrain entre 2005 et 2011, la démarche qualitative vise à répondre à la question suivante : de quoi les antirétroviraux sont-ils vraiment l’incorporation ? Les programmes d’accès au traitement constituent un pouvoir thérapeutique qui se structure comme une « politique de la vie » mettant en lien ARV, ONG et une histoire postcoloniale. La distance entre les prétentions et les réalités du pouvoir thérapeutique explique les ambivalences ressenties lors de l’incorporation biologique et sociale des ARV. Le pouvoir thérapeutique dans le contexte social centrafricain se caractériserait alors moins par des formes exclusivement biomédicales de subjectivité, que par un processus d’individuation fragmenté, basé sur des pratiques biomédicales souples, démonstratives et oublieuses. Il apparaît alors clairement que les programmes internationaux de traitement de l’infection à VIH contribuent à produire de l’oubli ou plus précisément à écrire l’oubli à partir des « pratiques scriptuaires »: l’oubli des histoires individuelles enchâssées dans des inégalités sociales insurmontables, mais aussi l’oubli d’une Histoire plus longue qui montre que l’infection à VIH est l’incorporation d’un passé colonial. Prendre un temps pour reconnaître ces temporalités du traitement paraît alors de plus en plus nécessaire pour construire un présent qui émancipe, plutôt qu’il ne répète. / This thesis proposes an ethnographic description and a sociological analysis of the arrival of antiretroviral (ARV) in Bangui. It highlights the encounter between an international program with an unprecedented scale and a local society hardly hit by the HIV infection. The qualitative approach, based on three years of fieldwork from 2005 to 2011, aims at answering the following question: what are ARVs really the incorporation of? Treatment programs represent a therapeutic power that is structured as a « politics of life » linking medicines, NGOs and postcolonial history. The distance between the claims and the realities of therapeutic power explains the ambivalence felt in the biological and social inclusion though ARVs. Eventually, we observe that the therapeutic power in the Central African social context is less characterized by exclusive biomedical forms of subjectivity than by a fragmented process of individuation based on flexible, demonstrative and forgetful biomedical practices It appears then increasingly clear that international programs for the treatment of HIV infection contribute to produce oblivion or more precisely write oblivion with "scriptural practices", which is to say the oblivion of individual stories embedded in insurmountable social inequality, but also the omission of a longer history which shows that HIV infection is the incorporation of a colonial past. Taking time to recognize these temporalities of treatment then appears increasingly necessary to build a present that empowers, rather than repeats. / Réalisé en co-tutelle avec le laboratoire Santé-Individu-Société, Ecole doctorale Interdisciplinaire Sciences et Santé, Université de Lyon, avec l'obtention du grade de docteur en sociologie.
60

Le traitement de l'oubli : épreuve de l'incorporation des antirétroviraux et temporalités des traitements du sida en Centrafrique

David, Pierre-Marie 04 1900 (has links)
No description available.

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