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Biological reactions to cobalt chrome wear particlesGermain, Marc Anthony January 2002 (has links)
No description available.
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Le métal et la chair : anthropologie des prothèses informatisées / The metal and the flesh : an anthropology of computerized prosthetic devicesDerian, Maxime 04 March 2013 (has links)
Diverses méthodes d'interfaçage Homme/Machine se confrontent et se complètent, suivant une gradation allant du peu invasif, le contact, jusqu'au totalement invasif, la greffe. Il ressort de cette recherche comparative portant sur le recours à des dispositifs implantés actifs comme sur l'utilisation de différentes prothèses détachables (membres bioniques, interfaces haptiques, informatique pervasive et systèmes de réalité augmentée), que l'implantation d'une endoprothèse est acceptée principalement parce qu'elle est perçue comme un moyen de prolonger l'espérance de vie ou d'améliorer significativement la qualité de vie. La pose des implants informatisés s'inscrit dans le contexte de l' »Humain réparé ». Dans ce domaine, des relations étroites entre patients, médecins, constructeurs d'implants et pouvoirs publics donnent lieu à la mise en place d'un accompagnement social structurant qui permet de limiter fortement de nombreuses dérives liées à un usage inapproprié. Cependant, il s'avère que l'essentiel de l'émergence actuelle de l' »Humain augmenté » ne découle pas du recours à des implants ni à des prothèses de membres, car la diffusion de ces appareils est limitée à un très faible effectif de la population mondiale. On assiste à un déferlement d'objets informatisés détachables (comme les smartphones et les tablettes tactiles, par exemple). Ces outils, diffusés massivement, sont principalement des prothèses cognitives. Or, l'usage fréquent de ces appareils semble pourtant en mesure d'exercer une forme de modification subtile de l'activité cognitive et peut transformer significativement les rapports sociaux ainsi que certains processus pédagogiques essentiels. / The research subject addresses the social use of man/machine interfaces. This thesis investigates invasive approaches (such as electronic surgical implants) as well as non-invasive approaches (nerve impulse detection using non-implanted sensors, haptic interfaces, augmented reality devices and ubiquitous computing). Such investigation aims at understanding the clinical and antropological issues generated by the multiplication of self-animated devices in the environment as well as in the human body. A clear point that stands out of this research is the following. Implants are not the key element in the process of « enhanced human » being which, by the way, concerns only a tiny portion of the world population. Implanted computing devices are mainly used an a strictly regulated context of « repaired human » (to keep the patients alive or to restore significantly their quality of life). It is worth mentioning that we are witnessing a surge of computer objects (such as smartphones, tablet computers...) in our social world as never before. Instances of computerized removable (detachable) prostheses are deeply pervasive nowadays. An increasing part of them can be described as cognitive prosthetics. A marketing very intense, presents this devices as fully harmless items. However, the way we constantly recourse (without clear social regulation) to these tools (or gadgets), the common daily exposure to different kinds of computer programs, raises fundamental pedagogic questions, causes upheavals in our relationship to our surrounding environment, let alone to man's cognitive activity.
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WORD-INITIAL CONSONANT CLUSTER PATTERNS IN THE ARABIC NAJDI DIALECTALGHMAIZ, BANDAR ABDULAZIZ 01 May 2013 (has links)
Unlike in Classical Arabic, this study hypothesized that word-initial consonant clusters exist in Najdi Arabic as a result of first vowel deletion. The goal of this study was to investigate the word-initial consonant cluster patterns of Najdi Arabic and measure the sonority scale of this particular position. Ten native Najdi Arabic speakers were asked to pronounce 24 words and 24 sentences that contained all the possible consonant cluster patterns that could occur in Najdi Arabic. The output of the subjects revealed that Najdi Arabic does have initial consonant clusters in certain environments and that the minimum sonority distance was one step between the first and second onsets. The study found that the sonority distance between the first and second onsets plays a role in forming initial consonant clusters in Najdi. Additionally, the existence of less-marked consonant clusters was found to be more frequent than the more marked ones. Finally, the study proposed examining the pattern of the deleted vowel in future studies to determine whether it plays a role in the results.
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A roentgen stereophotogrammetric analysis system for the measurement of subsidence of the femoral components in total hip arthroplastyGold, Brenda Joan 03 April 2017 (has links)
No description available.
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Fucoïdanes extraits de l'algue brune ascophyllum nodosum : effets pro-angiogéniques in vitro et régénération de valves pulmonaires acellularisées / Fucoidans extracted from brown seaweed Ascophyllum nodosum : in vitro pro-angiogenic effects and regeneration of acellularized porcine pulomnaryvalvesMarinval, Nicolas 07 December 2016 (has links)
Les fucoïdanes sont des polysaccharides sulfatés d’origine marine portant des activités biologiques diverses et comparables au glycosaminoglycanes (GAGs) endogènes. Leur utilisation comme agents thérapeutiques dans le traitement de maladies cardiovasculaires est envisagée. L’hétérogénéité structurelle liée à leur diversité naturelle et aux méthodes d’extraction et de purification, induisent des variations dans leurs propriétés physicochimiques et leurs effets biologiques. Le but de cette thèse est d’une part, d’établir études structure-fonction de fucoïdanes extraits de l’algue Ascophyllum nodosum sur leurs effets pro-angiogéniques in vitro (migration et formation de réseau vasculaire en 2D par des cellules endothéliales humaines, HUVECs) et le rôle des GAGs endogènes ; et d’autre part, l’étude du potentiel régénératif d’un biofilm de fucoïdane/VEGF appliqué sur des prothèses de valves cardiaques porcines acellularisées. Dans notre première étude, nos résultats montrent que la fraction de fucoïdane de bas poids moléculaire (LMWF, 4900 g/mol) induit des effets pro-angiogéniques plus importants qu’une fraction de moyen poids moléculaire (MMWF, 26700 g/mol) sur les HUVECs. De plus, le LMWF garde un potentiel proangiogénique avec des cellules HUVECs n’exprimant pas de GAGs endogènes et peut être internalisé par une endocytose dépendante de la clathrine dans laquelle les GAGs seraient partiellement impliqués. Dans notre deuxième étude, nos analyses démontrent que l’application d’un biofilm de fucoïdane/VEGF sur des valves pulmonaires porcines acellularisées induit un potentiel antithrombotique et permet l’adhérence et la survie des HUVECs. Ces travaux suggèrent que ce procédé permettrait la ré-endothélialisation de valves acellulaires pour le développement de bioprothèses auto-régénératives. / Fucoidans are marine sulfated polysaccharides carrying various biological activities comparable to endogenous glycosaminoglycans (GAGs).Their use as therapeutic agents in cardiovascular diseases treatment is considered. The structural heterogeneity linked to their natural diversity and to the extraction and purification methods induce variation in their physico-chemical properties and biological activities. The aim of this study is first to etablish a structure-function study of fucoidans extracted from the seaweed Ascophyllum nodosum on their in vitro pro-angiogenic effects (cell migration and vascular network formation by human endothelial cells, HUVECs) and the role of the endogenous GAGs ; and the study of the regenerative potential of the application of a biofilm of fucoidan/VEGF on acellular porcine heart valves. In the first part, our results show the fractionated low molecular weight fucoidan (LMWF, 4900 g/mol) induces higher pro-angiogenic effects than medium molecular weight fucoidan (MMWF, 26700 g/mol) on HUVECs. LMWF kept a pro-angiogenic potential with GAG-free HUVECs and is mainly endocyted in a clathrin-dependant pathway in which GAGs could be partially involved. In our second study, our data demonstrated that the application of the biofilm fucoidan/VEGF on acellular porcine pulmonary valves induce antithrombotic potential and allow the adhesion and survival of HUVECs. This work suggest that this method allows re-endothelialization of acellular heart valve and could be used to develop self-regenerative valve bioprosthesis.
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Estudo da resistência residual das cerâmicas de dissilicato de lítio submetidas a diferentes protocolos de fadiga / Mechanical behavior study of lithium disilicate ceramic subjected to different cycling protocolsBarcellos, Aline Serrado de Pinho [UNESP] 04 November 2016 (has links)
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Previous issue date: 2016-11-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do estudo foi avaliar o comportamento mecânico de uma cerâmica, à base de dissilicato de lítio, em ensaio de flexão com as extremidades fixas. Este estudo particular tem similaridade com caso real de aplicação de prótese em pacientes, o que melhora a avaliação do material quando comparado a ensaios convecionais como o ensaio de flexão em três pontos, com viga simplesmente apoiada. Para isso os corpos de prova foram submetidos à três tipos de envelhecimento: ciclagem mecânica, ciclagem termomecânica, ambas de acordo com os protocolos utilizados na literatura, e ciclagem intrabucal. A ciclagem intrabucal foi realizada por meio da utilização de um dispositivo intrabucal semelhante a uma placa oclusal, na qual foram instalados os corpos de prova, por meio de um dispositivo metálico próprio. Estas placas foram utilizadas em dez voluntários por oito horas, durante o período noturno. As amostras foram posteriormente submetidas ao ensaio mecânico de flexão de três pontos com as extremidades engastadas, para avaliação da resistência residual. Os resultados de resistência residual foram submetidos à análise estatística descritiva (média e desvio padrão) e inferencial, mediante o teste paramétrico de análise de variância (ANOVA) um fator e o teste de Tukey ( = 0,05). As amostras representativas de cada grupo foram observadas em microscópio eletrônico de varredura para análise fractográfica. O tipo de ciclagem influenciou no comportamento mecânico da cerâmica, apresentando significância estatística (p = 0,000) e o grupo de ciclagem intrabucal mostrou a menor resistência à flexão. A origem da fratura foi na zona de tração, porém observou-se uma origem secundária localizada em zona de torção. Pode-se concluir que os tipos de ciclagens influenciaram no comportamento mecânico da cerâmica de dissilicato de lítio. As ciclagens mecânica, termomecânica e intrabucal reduziram a resistência à flexão do material. A ciclagem intrabucal foi a que mais reduziu a resistência residual em flexão deste tipo de cerâmica. / This study aimed to evaluate the behavior of lithium disilicate ceramic in similar condition to a partial fixed prosthesis of three elements by subjecting to three types of aging (n=10): mechanical cycling, thermomechanical cycling, both according to the protocols used in the literature, and intraoral cycling. The intraoral cycling was accomplished by using an intraoral device, which is similar to an occlusal splint. They were installed with the samples (CP) by means of a metallic device that was fixed in balanced contact condition with the remainder of the occlusal surface of the plate. These plates were used in ten volunteers for eight hours during the evening. After fatigue, the samples were subjected to three-point bending tests with clamped ends to evaluate the residual strength. The residual strength results were submitted to descriptive statistics (mean and standard deviation) and inferential by the parametric analysis of variance (ANOVA), with one factor and Tukey test ( = 0.05). In addition, representative samples of each group were observed in a scanning electron microscope (SEM) for fractographic analysis. The cycling condition influenced the mechanical behavior of ceramic with statistical significance of (p = 0,000), and the intraoral cycling group showed the lowest residual flexural strength. In fractographic analysis, they showed that the origin of fracture was in the tensile zone, but there was a secondary fracture origin represented by a twisted zone. Therefore, all types of cycling influenced the flexural strength of the material.
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Análise da influência de diferentes tratamentos superficiais de sistemas cerâmicos na resistência de união adesiva /Vasconcellos, Walison Arthuso. January 2005 (has links)
Resumo: A cimentação é vital para o sucesso clínico de restaurações cerâmicas puras e é dependente de muitos fatores como a composição dos materiais cerâmicos, tratamento de superfície, e agente cimentante. O objetivo deste estudo foi investigar a influência de diferentes tratamentos superficiais (microjateamento, microjateamento + condicionamento com ácido fluorídrico e silicatização) de diferentes materiais cerâmicos (Duceram Plus - Degussa, IPS Empress 2 - Ivoclar Vivadent, In-Ceram Alumina - Vita) na resistência de união adesiva, usando o teste de microtração. Dezoito terceiros molares humanos superiores recém extraídos foram usados. Os dentes foram limpos e mantidos em solução salina com timol a 0.2% em temperatura ambiente. A superfície oclusal foi cortada perpendicular ao longo eixo do dente com disco diamantado em baixa rotação em máquina de corte. Os dentes foram aleatoriamente divididos em três grupos (n=6) da seguinte forma: Grupo I. Duceram Plus - Degussa; Grupo II. IPS Empress 2 - Ivoclar Vivadent; and Grupo III. In-Ceram Alumina - Vita. Moldagens foram feitas em todos os dentes com silicona de adição e obtidos troquéis em gesso tipo IV. Cada grupo foi dividido em três subgrupos (n=2), em função do tratamento superficial (A, B e C). Tratamento A: microjateamento com óxido de alumínio 50 mm. Tratamento B: microjateamento com óxido de alumínio 50 mm, seguido de condicionamento com ácido fluorídrico a 10%. Tratamento C: microjateamento com partículas de alumina com 100 mm (Rocatec pré), seguido por jateamento com partículas de alumina modificada por sílica (Rocatec plus)... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The cementation is vital for the clinical success of all-ceramic restorations and is dependent of many factors as composition of the ceramic materials, surface treatment and luting agent The purpose of the current study was to investigate the influence of different surface treatment (micro etching, micro etching + etching with fluoric acid and tribochemical silica coating process) of different ceramic materials (Duceram Plus - Degussa, IPS Empress 2 - Ivoclar Vivadent, In-Ceram Alumina - Vita) on bond strength at dentin, using the micro-tensile test. Eighteen freshly extracted human maxillary molars were used. The teeth were cleaned and stored in saline solution with timol 0.2% at room temperature. The occlusal surfaces were flattened perpendicular to long axis of the teeth with slow-speed diamond saw sectioning machine. The teeth were randomly divided into three groups (n=6 each) as follows: Group I. Duceram Plus - Degussa; Group II. IPS Empress 2 - Ivoclar Vivadent; and Group III. In-Ceram Alumina - Vita. Impressions were made of all teeth preparations with vinyl polysiloxane impression material and poured in a vacuum-mixed die material. Each of the 3 groups was divided into 3 sub-groups (n=2 each), in function of surface treatment (A, B e C). Treatment A: micro etching with 50 mm alumina particles. Treatment B: micro etching with 50 mm alumina particles + etching with 10% hydrofluoric acid. Treatment C: micro etching with 100 mm alumina particles (Rocatec pre) and 100 mm alumina particles modified with silica (Rocatec plus). All specimens were rinsed under running tap water and a silane solution was applied on ceramics specimens... (Complete abstract, click electronic address below). / Orientador: Alexandre Henrique Susin / Coorientador: José Roberto Cury Saad / Banca: Osmir Batista de Oliveira Júnior / Banca: Maria Salete Machado Cândido / Banca: Edson Alves de Campos / Banca: Rodrigo de Castro Albuquerque / Doutor
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Influencia dos tipos de tratamentos sobre a resistencia de união entre dentes e resinas acrilicas / Influence of types of treatments on the strength bond between teeth and acrylic resinsNaoe, Hilka Tiemi 02 March 2009 (has links)
Orientador: Rafael Leonardo Xediek Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-12T19:07:37Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: O objetivo neste estudo foi verificar a resistência da união ao cisalhamento entre as resinas acrílicas Clássico ou Onda-Cryl e o dente Trubyte-Biotone, sob a influência de diversas formas de retenção, compreendendo nenhum tratamento (controle), perfuração com broca, jateamento com partículas de óxido de alumínio, condicionamento com monômero, condicionamento com primer e interações. Noventa matrizes retangulares, medindo 20mm de largura por 35mm de comprimento, foram confeccionadas com cera utilidade e incluídas na parte inferior de muflas metálicas ou plásticas, com gesso pedra tipo III Herodent. As matrizes retangulares foram removidas depois de plastificadas com água em ebulição e os moldes de gesso revestidos com silicone laboratorial, nos quais foram incluídos um dente molar com a base contendo um cilindro de cera de 6mm de diâmetro por 25mm de comprimento. O conjunto dente-cilindro em cera foi recoberto com uma camada de silicone e a mufla preenchida com gesso pedra. Depois da presa do gesso, o conjunto dente-cilindro em cera foi removido, o bastão em cera retirado, o dente limpo com detergente e as bases submetidas aos tratamentos de acordo com o protocolo e recolocadas nos moldes de silicone. As resinas acrílicas termopolimerizáveis foram proporcionadas na relação volumétrica de 3/1 (polímero/monômero), adaptadas na fase plástica nos moldes de silicone e prensadas em prensa hidráulica de bancada. As muflas metálicas foram levadas à termopolimerizadora automática para polimerização da resina no ciclo em banho de água à temperatura de 74ºC durante 9 horas. As muflas plásticas foram colocadas em forno de microondas para polimerização da resina, calibrado com 900W de potência, para o ciclo de: fase I - 3 minutos com 40% da potência, fase II - 4 minutos com potência 0% e fase III - 3 minutos com 90% da potência e esfriamento das muflas em bancada. Depois da demuflagem, os corpos-de-prova foram armazenados em água destilada à temperatura de 37ºC durante 24 horas. Depois da armazenagem, os corpos-de-prova foram submetidos ao teste de resistência ao cisalhamento na máquina de ensaios universal Instron, com velocidade de 1mm/minuto. Os resultados submetidos à análise de variância e as médias ao teste de Tukey (5%) mostraram que os valores da união entre dentes artificiais e resinas acrílicas não apresentam diferença estatística significativa, quando comparadas independentemente dos tipos de tratamentos. Na análise dos tipos de tratamentos, independentemente da resina acrílica, o grupo que recebeu jateamento+adesivo apresentou média com diferença estatística significativa com o grupo perfurado+adesivo. Os demais grupos não apresentaram diferença estatística significativa. Quando os tratamentos foram considerados em cada resina, na Clássico não houve diferença significativa entre eles e na Onda-Cryl os tratamentos controle e perfurado+adesivo foram diferentes estatisticamente dos grupos jateado+ monômero e jateado+adesivo. Os demais grupos não apresentaram diferenças estatísticas. Na comparação entre resinas, somente o grupo controle apresentou diferença estatística significativa com o maior valor para a resina Onda-Cryl / Abstract: The purpose of this study was to verify the shear bond strength between denture tooth Trubyte-Biotone and the acrylic resins Clássico and Onda-Cryl, under the influence of various forms of treatments, including no treatment (control), retention groove, sandblasting with aluminum oxide particles, monomer application, primer application, and interactions. Ninety wax rectangular mold patterns (20 mm in width and 35 mm in length), were poured into a traditional brass flask or metal with type III dental stone that was proportioned and manipulated following the manufacturer's recommendations. After wax patterns removal, the stone mold was filled with a layer of laboratory silicone putty. Identical model acrylic molar teeth with a wax stick (6mm diameter and 25mm long) attached at the ridge lap surface were partially embedded into the silicone layer. The resultant tooth/wax stick set was then covered with a layer of laboratory silicone putty. After dental stone isolation with petroleum jelly, the flask was completely poured with type III dental stone and pressed in a hydraulic press bench. Following, the tooth/wax stick set was deflasked and the wax stick removed from the tooth ridge lap. The tooth was brushed with a solution of hot water and liquid detergent to eliminate the wax residuos. Heat-cured denture base acrylic resins were prepared using a ratio of volume 3/1(polymer/monomer), adapted on stage in plastic molds made of silicon and pressing into bench hydraulic press. The metal flask were conventional packed, polymerized in a hot water bath at 74oC for 9 hours in polymerizing unit, and deflasked after flask cooling at room temperature. The plastic flask were placed in the microwave oven for curing the acrylic resin, calibrated with 900W of power for the cycle: Phase I - 3 minutes with 40% of the power, phase II - 4 minutes with 0% power and phase III - 3 minutes with 90% of the power and flask cooling at room temperature. After deflasked, all specimens were stored in distilled water at a temperature of 37oC for 24 hours, and they were performed the shear bond testing in an Instron machine, using a cross-speed of 1mm/minuto. The results were submitted to ANOVA and Tukey's test (5%) showed that the values of the shear bond strength between artificial teeth and acrylic resins were not statistically significant when compared regardless of the types of treatments. In the treatment type analysis, regardless of acrylic resin, the sandblasting+adhesive group showed bond strength values with significant statistically difference when compared to groove+adhesive group. The other experimental groups were not statistically different. When the treatments were considered in each resin, in the Classico acrylic resin there was no significant difference between them. In Onda-Cryl, control and groove+adhesive treatments were statistically different of the sandblasting+monomer and sandblasting+adhesive groups, while the other showed no statistical differences. In the comparison between resins, only the control group showed statistically significant differences, with the greatest value for the Onda-Cryl acrylic resin / Mestrado / Mestre em Materiais Dentários
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Surface changes and screw loosening of the titanium abutments for one-piece implant supported fixed complete denture.Qazali, Ahmad A. 08 November 2016 (has links)
No description available.
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Experimental and analytical study of a knee prothesisPadture, Sunil Prabhakar January 1994 (has links)
No description available.
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