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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.
1001

Prevence šikany na základních školách / Prevention of bullying in elementary schools

Herák, Robert January 2014 (has links)
In my diploma thesis I analysed the success of the implementation of the policy on the prevention and solution of bullying at primary schools in the Czech Republic. I was based on the theory of implementation and street level bureaucracy. The hypothesis for the success of the implementation of this policy is the acceptance of schools, teachers, and the Director of the schools. To analyze the success of the implementation of the policy on the prevention and solution of bullying, I took advantage of the available professional literature, I've analyzed the current documents, which shall submit to the Ministry of Education (for example Methodological guideline for the prevention and solution of bullying), I have used the knowledge from the survey, focus groups and regular meetings of Directors, which realizes the company SCIO. I graduated five structured interviews with Directors of elementary schools. In the next section, I focused on the quantitative research, survey for the Director of elementary schools. I focused on the Director of elementary schools, because they are the key actors for the implementation of educational policies and have enough information about the everyday school practice. The first section of the quantitative research deals with the education of teachers in schools the issue of...
1002

Interdissiplinere argeologiese navorsing van musiekinstrumente in antieke Israel/Palestina gedurende die ystertydperk / An interdisciplinary achaeological research of musical instruments in ancient Israel/Palestine during the iron age

Sieberhagen, Mana 01 1900 (has links)
(M.A. (Bybelse Argeologie))
1003

Étude transversale sur l’asepsie des articles transférés entre la clinique et le laboratoire dentaire et de l’instrumentation de laboratoire

Bezerianos, Joanna 09 1900 (has links)
Les mesures de contrôle de la contamination croisée sont principalement concentrées dans la salle opératoire dentaire alors que les articles transférés entre la clinique et le laboratoire dentaire et les instruments de laboratoire ont reçu peu d’attention. Cette étude vise à documenter l’application des mesures d’asepsie sur ces articles par les professionnels du domaine dentaire ainsi que leurs perceptions entourant ces mesures. Un questionnaire autoadministré et anonyme a été envoyé à un échantillon aléatoire des dentistes, denturologistes et directeurs de laboratoire dentaire qui étaient inscrits aux listes des ordres professionnels en juin 2008 dans la province de Québec. Des 1100 questionnaires envoyés, 376 ont été retournés remplis. Presque trois quarts (72,1 %) des répondants affirment faire l’asepsie des instruments de laboratoire et 74,9 %, la désinfection des articles transférés mais avec des pourcentages variables selon le groupe d’articles (empreintes, prothèses, etc.). Seulement 9,1 % de professionnels identifient de façon générale les articles désinfectés avant l’envoi. Plus de la moitié des professionnels (51,4 %) trouvent qu’ils n’ont pas assez d’information sur l’asepsie des articles transférés et 62,4 %, qu’elle est difficile à appliquer. Cette étude est la première réalisée auprès des trois groupes de professionnels et la première à étudier leurs perceptions entourant l’asepsie des articles transférés et de l’instrumentation de laboratoire. Nous avons démontré que l’application des mesures d’asepsie à ces articles par les professionnels du domaine dentaire n’est pas toujours conforme aux normes proposées et qu’il existe un besoin de renforcer leur application, surtout en ce qui a trait aux articles transférés. / Infection control practices have been mainly concentrated in the dental operatory whereas the articles transferred between the dental clinic and the dental laboratory as well as laboratory instruments have received less attention. This study attempts to document the practices of dental care professional implicated in the fabrication of dental prosthesis as to the asepsis of these items as well as their perceptions towards it. In June 2008 an auto-administrated and anonymous questionnaire was sent to a random sample of dentists, denturologists and dental laboratory directors licensed to practice in the province of Quebec (Canada). From the 1,100 questionnaires sent, 376 were returned filled-in. Almost two thirds of responders (72.1%) claim to disinfect or sterilize laboratory instruments and 74.9% to disinfect transferred articles, with percentages varying according to the group of articles (impressions, prosthesis, etc.). However, only 9.1% regularly identify disinfected work. More than half of the responders (51.4%) think it is difficult to apply a form of asepsis on transferred articles and 62.4% believe there is a lack of information towards it. This study is the first to have been addressed simultaneously to the three groups of professionals and the first to question them on their perceptions. It demonstrated that the application of asepsis measures to transferred articles and laboratory instruments by dental care professionals is not always complying with existing recommendations. There is a need to reinforce their application, especially of asepsis measures on transferred articles.
1004

A Study of Modern Automotive Tune-Up Equipment Used in Fort Worth, Texas

Shabbot, Kadhum 08 1900 (has links)
The problem with which this investigation was concerned was that of determining the use of modern automotive tune-up equipment as used by the automotive garages in the Fort Worth area. The data for this study were provided by fifteen garages of the Fort Worth area. Of the Fort Worth garages using electronic equipment to perform a tune-up, few appear to have the adequate equipment and few appear to make more use of the equipment. In addition, a deficiency seems evident in the use of the electronic computer in performing tune-ups.
1005

La diffusion du contrôle à la source des eaux pluviales urbaines : confrontation des pratiques à la rationalité hydrologique / The diffusion of source control for urban stormwater management : a comparison between the current practices and the hydrological rationality

Petrucci, Guido 11 July 2012 (has links)
La gestion des eaux pluviales urbaines connait une évolution majeure depuis les années 1960 : d'une stratégie basée sur l'évacuation rapide et totale des eaux pluviales de la ville, on passe progressivement à une stratégie de contrôle à la source (CS). Ces 10 dernières années ont vu une généralisation du CS, ainsi qu'en témoigne l'augmentation du nombre de réglementations de rejet. Ces dernières imposent, dans les nouvelles parcelles urbanisées, la réalisation d'ouvrages ayant pour fonction de réguler et/ou de retenir les eaux pluviales : les techniques alternatives (TA). Une systématisation de ces réglementations ne va pas manquer de générer dans l'avenir de nombreux bassins versants urbains fortement équipés en TA, et dont le comportement hydrologique sera déterminé par les réglementations appliquées. Il apparaît que le choix d'une réglementation par une collectivité est un choix complexe et, d'une collectivité à l'autre, des logiques différentes sont appliquées, dont la cohérence globale peut être discutée. Cette thèse questionne et analyse les politiques de CS, et en particulier les réglementations de rejet, dans une perspective de compréhension de leurs effets hydrologiques dans le long terme. Elle comprend deux analyses complémentaires : nous étudions d'abord l'évolution des politiques de CS dans six collectivités en France, afin de déterminer les logiques appliquées dans le choix des réglementations. Nous présentons ensuite une analyse hydrologique des conséquences de ces réglementations sur le comportement de bassins versant urbains "modèles". Cette analyse, centrée sur la modélisation hydrologique des bassins, permet de questionner les politiques de CS actuelles, mais aussi de discuter des outils que l'hydrologie urbaine peut fournir pour permettre la mise en place de politiques de CS cohérentes, en phase avec le fonctionnement hydrologique des bassins versants / Urban stormwater management is facing a major evolution since 1960: from a strategy based on the complete and fast conveyance of stormwater outside of the urban area, to a strategy based on source control (SC). Recently, SC is becoming a common practice, in connection with the increasing diffusion of flow regulations. These regulations prescribe, for all new urban development, to build facilities (Best Management Practices, BMP) to reduce the flow-rate or the volume of stormwater entering the sewer system. A wide application of flow regulations will determine the future hydrological behaviour of many urban catchments. The choice of a regulation is a complex task for local authorities, involving several logics, whose global coherence can be discussed. This thesis analyses SC policies and regulations and discusses them in terms of their long-term hydrological effects. Two complementary approaches are developed. The first is based on the analysis of the evolution of SC policies in six French authorities, and it aims to define and discuss the logics applied. The second consists in the hydrological modelling of the consequences of SC regulations on the behaviour of two experimental catchments. This hydrological analysis allows (i) to evaluate the pertinence of actual SC policies and (ii) to discuss which tools urban hydrology can provide to support the development of coherent SC policies, according to the hydrological functioning of urban catchments
1006

L'action publique liée à l'alimentation et les stratégies des entreprises de l'industrie alimentaire en France / Public action related to food and business stratefies of food in France

Messaoudene, Leïla 05 December 2013 (has links)
Le mix instrumental de la politique alimentaire française induit une responsabilisation des acteurs de l’industrie agroalimentaire. Toutefois, ce partage d’enjeux est traversé par des logiques contradictoires. Dans cette étude, nous proposons d’analyser dans quelle mesure les instruments de l’action publique liée à l’alimentation interagissent avec les stratégies des entreprises de l’industrie alimentaire française.Pour y parvenir, nous nous appuyons en particulier sur la logique instrumentale de la politique alimentaire, l’approche par les parties prenantes et la théorie néo-institutionnelle. Nous analysons, grâce à la méthode de l’étude de cas unique, enchâssée, les réactions stratégiques d’une pluralité d’acteurs autour de la politique alimentaire.Cette étude contribue à l’analyse des politiques publiques, dans une perspective organisationnelle en l’appliquant au domaine de l’alimentation.Cette recherche a aussi permis d’identifier des modalités de renouvellement de l’action publique, avec une figure étatique qui se renforce. L’Etat, grâce à la mobilisation intelligente de ces parties prenantes, augmente sa capacité d’influence sur certains pans de la société et de la vie quotidienne des citoyens. Finalement, il semblerait que le désengagement observé de l’Etat soit dans certains domaines à relativiser. Derrière un effacement apparent, l’Etat continue à jouer son rôle mais selon des modalités renouvelées, sans doute plus adaptées au contexte actuel. / The instrumental mix of French food policy induces a responsibility to the players in the food industry . However, this share issue is crossed by conflicting logics. In this study , we propose to analyze to what extent the instruments of public policy related to food interact with the business strategies of the French food industry.To achieve this, we rely particularly on the approach by stakeholders . We analyze , using the method of the single case study , embedded , strategic reactions of a plurality of actors around food policy.This study contributes to the analysis of public policies, an organizational perspective by applying it to the field of nutrition.This research also identified renewal terms of public policy , with a state figure is increasing. The State, through intelligent engagement of these stakeholders , increases its influence on some sections of society and daily life of citizens.Finally , it seems that the disengagement of the state is observed in some areas relative. Behind an apparent deletion, the state continues to play its role, but in a manner renewed, probably more suited to the current context.
1007

Comparison of the mechanical properties of engine-driven nickel- titanium instruments manufactured by different thermal treatments / Comparação das propriedades mecânicas de instrumentos mecanizados de níquel-titânio fabricados com diferentes tratamentos térmicos

Alcalde, Murilo Priori 03 April 2018 (has links)
The aim of this study was to evaluate the mechanical properties of engine-driven Nickel-Titanium instruments manufactured by different thermal treatments. In the first part of this study, 60 reciprocating instruments were used (n=20): Reciproc R25 (REC 25.08), Unicone L25 (UNC 25.06) e Prodesign R 25 (PDR 25.06). The cyclic flexural fatigue resistance was performed measuring the time to failure in an artificial stainless steel canal with a 60º angle and a 5 mm radius of curvature (n=10). The torsional test was performed according to ISO 3630-1, measuring the torque and angle of rotation at failure in the 3 mm from the tip portion (n=10). Additionally, the fractured surface of each instrument was examined by scanning electron microscopy (SEM) to assess the topographic features of the fractured surface. Data were analyzed using one was analysis of variance ANOVA and Tukey test, the level of significance was set at 5%. The results of the cyclic flexural fatigue showed that PDR 25.06 presented significantly higher values than the other groups (P<0.05). REC 25.08 showed higher fatigue resistance than UNC 25.06 (P<0.05). In relation to the torsional test, the PDR 25.06 presented the lowest torque load than REC 25.08 and UNC 25.06 (P<0.05). In addition, there was no significant difference between REC 25.08 and UNC 25.06 (P>0.05). The PDR 25.06 and UNC 25.06 showed higher angular rotation until fracture than REC 25.08 (P<0.05). No difference was found between PDR 25.06 and UNC 25.06. All the instruments showed typical topographic features of cyclic flexural and torsional fatigue. The second part of this study evaluated the cyclic flexural and torsional fatigue resistance of reciprocating instruments Reciproc Blue (RB 25.08), WaveOne Gold Primary (WOG 25.07) and Prodesign R 25 (PDR 25.06) (n=20). The cyclic flexural fatigue test was performed with the same previsoly described device, using a root curvature with 60º and a 5 mm radius (n=10) and the torsional test was performed according to ISO 3630-1 (n=10). The fractured surface of each instrument was examined by scanning electron microscopy (SEM). Data were analyzed using one was analysis of variance ANOVA and Tukey test, the level of significance was set at 5%. The results of the cyclic flexural fatigue test showed that PDR 25.06 presented significantly higher values than the other groups (P<0.05). RB 25.08 showed higher fatigue resistance than WOG 25.07 (P<0.05). The torsional test showed that PDR 25.06 had lowed torsional load (P<0.05). No difference was found between RB 25.08 and WOG 25.07 (P>0.05). In relation the angular rotation, the PDR 25.06 showed higher angular rotation values than RB 25.08 and WOG 25.07 (P<0.05). RB 25.08 presented higher angular values than WOG 25.07 (P<0.05). All the instruments showed typical topographic features of cyclic flexural and torsional fatigue. The third part of this study was to evaluate the torsional fatigue resistance of NiTi rotary glide path instruments. The torsional test was performed according to ISO 3630-1, measuring the torque and angle of rotation at failure in the 3 mm from the tip portion. A total of 56 glide path instruments were used (n=8): Logic 25.01 (LOG 25.01), Logic CM 25.01(LOG CM 25.01), Proglider 16.02 (PGD 16.02), Hyflex GPF 15.01, 15.02, 20.02 (HGPF) and Mtwo 10.04. The fractured surface of each instrument was examined by scanning electron microscopy (SEM). Data were analyzed using one was analysis of variance ANOVA and Tukey test, the level of significance was set at 5%. The results showed that LOG 25.01 had a significantly higher torsional load than the other groups (P<0.05). The PGD 16.02 had significantly difference in comparison with HGPF 15.01 and 15.02 (P<0.05). LOG CM 25.01 had higher torsional load than HGPF 15.01 and 15.02 (P<0.05). No difference was found among Mtwo 10.04, HGPG 15.01, 15.02 and 20.02. In relation the angular rotation, LOG CM 25.01 and HGPF 15.01 presented the highest values (P<0.05). PGD 16.02 had the lowest values (P<0.05) followed by Mtwo 10.04. LOG 25.01 had higher angle of rotation than PGD 16.02 and Mtwo 10.04 (P<0.05). All the instruments showed typical topographic features of torsional fatigue. / O objetivo deste estudo foi avaliar o comportamento mecânico de instrumentos mecanizados de Níquel-Titânio (NiTi) fabricados com diferentes tratamentos térmicos. Na primeira parte do estudo foram utilizados 60 instrumentos reciprocantes para a realização dos teste de fadiga cíclica flexural e torcional (n=20): Reciproc R25 (REC 25.08), Unicone L25 (UNC 25.06) e Prodesign R 25 (PDR 25.06). O teste de fadiga cíclica flexural foi realizado com o objetivo de mensurar o tempo para a fratura dos instrumentos em um canal artificial de aço inoxidável com curvatura com 60º de angulação e 5 mm de raio (n=10). Para o teste de torção, os 3 mm inicias das pontas dos instrumentos foram fixadas em um aparelho de torção (n=10), de acordo com a norma ISO 3630-1. Este teste foi realizado com o objetivo de mensurar o torque máximo e o ângulo de rotação suportado pelos instrumentos até sua fratura. Adicionalmente, todos os fragmentos dos instrumentos fraturados foram examinados em microscopia eletrônica de varredura (MEV) para avaliar as características topográficas da superfície da área da fratura. A análise-estatística foi realizada utilizando o teste de análise de variância com um fator ANOVA e teste de Tukey, o nível de significância foi de 5%. Os resultados de fadiga cíclica flexural demonstraram que o PDR 25.06 apresentou maior tempo para a fratura do que os outros grupos (P<0.05). O instrumento REC 25.08 apresentou maior resistência a fadiga cíclica flexural do que o UNC 25.06 (P<0.05). O teste de torção demonstrou que o PDR 25.06 apresentou significantemente menor resistência torcional do que o REC 25.08 e UNC 25.06 (P<0.05). Além disso, não houve diferença entre REC 25.08 e UNC 25.06. Com relação ao ângulo de rotação, o PDR 25.06 e UNC 25.06 apresentaram diferença significante quando comparado ao REC 25.08. Não houve diferença entre PDR 25.06 e UNC 25.06 (P>0.05). Todos os instrumentos apresentaram característica topográficas típicas de fadiga cíclica flexural e torcional. Na segunda parte deste estudo avaliou-se a fadiga cíclica flexural e torcional dos instrumentos reciprocantes Reciproc Blue R25 (RB 25.08), WaveOne Gold Primary (WOG 25.07) e Prodesign R 25 (PDR 25.06) (n=20). O teste de fadiga cíclica flexural foi realizado com dispositivo descrito anteriormente, utilizando curvaturas de 60º e 5 mm de raio (n=10). O teste de torção foi realizado de acordo com a norma ISO 3630-1 (n=10). Todos os fragmentos dos instrumentos fraturados foram examinados em microscopia eletrônica de varredura (MEV) para avaliar as características topográficas da superfície da área da fratura. A análise-estatística foi realizada utilizando o teste de análise de variância com um fator (ANOVA) e teste de Tukey, o nível de significância foi de 5%. Os resultados de fadiga cíclica flexural demonstraram que o PDR 25.06 apresentou a maior resistência a fadiga cíclica flexural do que dos outros grupos (P<0.05). O RB 25.08 apresentou maior tempo para à fratura do que o WOG 25.07 (P<0.05). O teste de torção, o PDR 25.06 apresentou a menor resistência à torção do que os outros grupos (P<0.05). Não houve diferença significante entre RB 25.08 e WOG 25.07 (P>0.05). Em relação ao ângulo de rotação, o PDR 25.06 apresentou maiores valores quando comparados com RB 25.08 e WOG 25.07. O RB 25.08 apresentou diferença significante quando comparado com WOG 25.07. Todos os instrumentos apresentaram características topográficas típicas de fadiga cíclica flexural e torcional. Na terceira parte deste estudo avaliou-se a resistência torcional de instrumentos empregados para patência do canal radicular, de acordo com a norma ISO 3630-1. Foram utilizados 56 instrumentos rotatórios (n=8): Logic 25.01 (LOG 25.01), Logic CM 25.01 (LOG CM 25.01), Proglider 16.02 (PGD 16.02), Hyflex GPF 15.01, 15.02, 20.02 (HGPF) e Mtwo 10.04. Os fragmentos dos instrumentos fraturados foram examinados em microscopia eletrônica de varredura (MEV) para avaliar as características topográficas da superfície da área da fratura. A análise-estatística foi realizada utilizando o teste de análise de variância com um fator ANOVA e teste de Tukey, o nível de significância foi de 5%. Os resultados demonstraram que o LOG 25.01 apresentou significantemente maior resistência torcional do que os demais grupos (P<0.05). O grupo da PGD 16.02 apresentou diferença significante quando comparado com HGPF 15.01 e 15.02 (P<0.05). O LOG CM 25.01 apresentou maior resistência torcional do que o grupo do HGPF 15.01 e 15.02 (P<0.05). Não houve diferença significante entre os intrumentos Mtwo 10.04 e HGPF 15.01, 15.02 e 20.02. Com relação ao ângulo de rotação, o LOG CM 25.01 e HGPF 15.01 apresentaram os maiores valores (P<0.05). O PGD 16.02 apresentou o menor valor de todos os grupos (P<0.05) seguido pelo Mtwo 10.04. O LOG 25.01 apresentou maiores ângulos de rotação do que o PGD 16.02 e Mtwo 10.04 (P<0.05). Todos os instrumentos apresentaram característica topográficas típicas de fadiga torcional. As características da secção transversal, tipo de núcleo, taper e o tratamento térmico possuem forte influência sobre as propriedades mecânicas dos instrumentos de NiTi. No entanto, o tratamento térmico é um dos fatores primordiais para maior flexibilidade dos instrumentos. O instrumento PDR 25.06 apresentou maior resistência à fadiga cíclica flexural e maior ângulo de rotação no teste de torção do que todos os outros instrumentos reciprocantes avaliados. No entanto, menor resistência torcional. Os intrumentos LOG 25.01 apresentaram maior resistência torcional e o LOG CM 25.01 maiores ângulos de rotação.
1008

Conception et évolution du régime français de régulation de la sûreté nucléaire (1945-2017) à la lumière de ses instruments : une approche par le travail de régulation / Design and evolution of the risk regulation regime of nuclear safety in France (1945-2017) in the light of its instruments : an approach through regulatory work

Mangeon, Michaël 29 June 2018 (has links)
Cette thèse étudie la conception et l’évolution du régime de régulation de la sûreté nucléaire en France entre 1945 et 2017. En nous appuyant sur le concept de régime de régulation (Hood et al, 2001), nous avons proposé une modélisation qui permet d’identifier trois périodes, correspondant à trois « philosophies » : la première (19451969) voit la formation d’un embryon de régime de régulation au sein du CEA marqué par « l’expérimentation et l’autocontrôle ». La seconde, la « raisonnable souplesse » (19691986), est marquée par une réorganisation institutionnelle mais laisse de nombreuses marges de manœuvre aux experts et exploitants, dans un contexte de développement industriel intensif. Enfin, la troisième période (1986-2017) voit le développement d’un régime « en recherche d’auditabilité », produit d’une hybridation entre le régime de la « raisonnable souplesse » et un idéaltype standardisé répondant aux bonnes pratiques internationales (ouverture, transparence et indépendance du régulateur et de l’expert). Pour expliquer les évolutions du régime, nous nous sommes focalisés sur une de ses composantes, les règles, analysées comme des instruments de régulation, et avons qualifié de « travail de régulation », l’ensemble des activités et interactions d’un groupe d’acteurs qui agissent pour concevoir, transformer et implémenter ces instruments (pour notre cas, les règles et guides en matière d’inondation). Nous défendons l’idée que ce travail de régulation, à la fois cognitif, politique, social et organisationnel, a pour effet, au-delà de la production d’un instrument, d’explorer des évolutions du régime de régulation, tout en construisant les savoirs mobilisés dans les instruments de régulation, et simultanément, le collectif interorganisationnel qui les partage. Ce processus expliquerait la relative lenteur du processus d’hybridation en cours. / This thesis studies the design and evolution of the risk regulation regime of nuclear safety in France between 1945 and 2017. Based on the concept of “risk regulation regimes” (Hood et al, 2001), we propose a model that identifies three periods, corresponding to three types of "philosophies". During the first period (1945-1969), an embryonic regulatory regime developed within CEA is characterized by "experimentation and autocontrol". The second period of "reasonable flexibility" (1969-1986) is marked by an institutional reorganization but leaves many room for maneuver to experts and operators, in a context of intensive industrial development. Finally, during the third period (1986-2017), a regime "in search of auditability" is the product of hybridization between the regime of "reasonable flexibility" and a standardized regime responding to international good practice (openness, transparency, and regulator’s and expert’s independence). To explain the evolution of the regime, we focus on one of its components, the rules, which we analyze as regulatory instruments, and we describe as "regulatory work" all activities and interactions of a group of agents who act to design, transform and implement these instruments (for our case, flooding rules and guides). We argue that regulatory work is at the same time cognitive, political, social and organizational, and, beyond producing an instrument, it results in exploring evolutions of the regulation regime, while building both the knowledge mobilized in regulatory instruments and interorganizational collective that shares them. This process would explain the relative slowness of the ongoing hybridization process.
1009

Morfometria comparativa in vitro do desgaste dentinário do terço cervical de raízes mésio-vestibulares de primeiros molares superiores produzido por instrumentos rotatórios de aço e de níquel-titânio / In vitro morphometric study of cervical third dentin wearing in upper molar mesiobuccal roots after preparation with iron burs and rotary nickel-titanium instruments

Sá, Júnio Pereira de 30 October 2002 (has links)
No preparo dos canais radiculares, eminentemente os curvos, a abordagem cérvico-apical amplamente difundida promovendo a dilatação da região cervical do canal radicular previamente à atuação de instrumentos em sua região apical constitui técnica e inegavelmente uma forma adequada, tanto do ponto de vista mecânico como microbiológico, de interagir com o espaço endodôntico em busca de uma experiência bem sucedida e previsível. De outra forma, os mais recentes instrumentos endodônticos, muito mais flexíveis em decorrência das novas ligas de baixo módulo de elasticidade empregadas em sua fabricação e dotados de novos índices de conicidade, surgem melhorando tais perspectivas. Desde o surgimento da liga de Níquel-Titânio na Endodontia, na década de oitenta, uma gama imensa de instrumentos desta derivados e para serem empregados com dispositivos mecânicos, eletromecânicos ou pneumocânicos, têm reavivado a esperança de se obter um dispositivo ideal que simulando a cinemática manual supere as limitações operacionais decorrentes, principalmente, da configuração anatômica do canal radicular. Assim, neste experimento verificou-se o desempenho de quatro diferentes recursos técnicos no desgaste da região cervical do canal radicular. Constituíram-se quatro amostras, cada qual composta de 10 espécimes (raízes mésio-vestibulares de primeiros molares superiores), para serem preparadas com (i) Brocas Gates-Glidden, (ii) Brocas Largo-Peeso, (iii) ProFile® .04/.06 & Orifice Shapers e (iv) Pow-R Coronal Shapers. Imagens digitais obtidas antes e após o preparo do canal radicular foram analisadas também digitalmente estudo morfométrico computadorizado avaliando-se a variação das áreas das mesmas em função do desgaste promovido pelos referidos instrumentos. Todos os instrumentos produziram desgaste de ambas as paredes, mesial e distal, do canal radicular na região analisada. A análise estatística das variações de área para o fator parede mesial não mostrou diferenças estatisticamente significantes entre os grupos experimentais para =5%. No entanto quando da comparação dos grupos experimentais para o fator parede distal verificou-se diferenças estatisticamente significantes entre os grupos #1 e #3 para =5%. Ainda, para o fator área total (paredes mesial e distal) verificou-se diferenças estatisticamente signifcantes entre os grupos #3 e #4 para =5%. Concluiu-se que todos os instrumentos testados produzem desgaste tanto da parede mesial como da parede distal do canal radicular e, conseqüentemente, da estrutura dentinária global da região cervical do canal radicular. Por outro lado verificou-se uma tendência da Broca Gates-Glidden em promover maior desgaste da parede distal que o Sistema ProFile® .04/.06 & Orifice Shapers e do Sistema Pow-R Coronal Shapers em promover maior desgaste da estrutura toal que o Sistema ProFile® .04/.06 & Orifice Shapers. / Nowadays is common sense among endodontists that in root canal preparation, mainly the curved ones, the crown-down approach enlarging the cervical third prior instrumentation of the apical third regions provides better interaction between the instrument and the canal walls than the conventional methods. Technically it provides an adequate form to achieve the best and predictable results in cleaning and shaping the root canal system. Additionally the most recent nickel-titanium made endodontic instruments more flexible than the stainless steel instruments and the new taper design have been appeared to improve the endodontic panorama. Since the introduction of the nickel-titanium alloy in Endodontics by Walia et al. in 1988 a number of instruments produced by such alloy in conjunction with the engines new generation have brought new perspectives to deal tridimensionally with the still challenger endodontic space. In this study the performance of four different instruments in the root canal cervical third enlargement was evaluated. Four experimental groups comprised by ten upper molars mesiobuccal roots each were prepared by either (i) Gates bur, (ii) Largo bur, (iii) Profile® .04/.06 & Orifice Shapers or (iv) Pow-R Coronal Shapers. Before and after preparation digitally acquired images were evaluated for area changes within both mesial and distal root canal walls. All instruments produced some amount of wear in both walls and the distals have changed more than the mesials in most times probably due an excentric performance of all evaluated instruments. Comparison of root canal walls wearing among the four experimental groups showed no statistically significant differences (=5%) for mesial wall. However, statistically analyze (=5%) showed significant differences between Experimental Group #1 (Gates-Glidden burs) and Experimental Group #3 (Profile® .04/.06 & Orifice Shapers) for distal walls with the first showing greater wearing than the latter. Also, the results showed statistically significant differences between Experimental Group #4 (Pow-R & Coronal Shapers) and Experimental Group #3 (Profile® & Orifice Shapers) for the entire structure i.e. mesial and distal walls with the first showing the greater than the latter wearing . It was concluded that all tested instruments wear so the mesial as the distal root canal walls. Experimental results have showed that in first upper molaras mesiobuccal roots Gates-Glidden bur for distals and Pow-R nickel-titanium instruments for both walls, i.e. the cervical dentin entire structure, are supposed to wear more root canal cervical third dentin than the others instruments which they were compared.
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De l’innovation des instruments de politique publique : développement d'une méthode de conception combinatoire autour d'un langage algorithmique et application au dispositif des certificats d’économie d’énergie / Innovation of public policy instruments : development of a combinatory design method via an algorithmic language and application to the energy saving certificates scheme

Baïz, Adam 06 December 2018 (has links)
En dépit de ses diverses caractérisations, la nature innovante des instruments de politique publique semble consacrer trois types d’innovation : (a) soit, des imitations, à un glissement de modalités près, d’instruments préexistants ; (b) soit des hybridations d’instruments plus ou moins contraignants ; (c) soit des assemblages d’instruments de nature méta-instrumentale. En admettant alors que tous les instruments découlent les uns des autres par le biais de ces trois chemins de conception, nous avons cherché à produire une méthode de conception fondant concomitamment, et autour d’un même modèle-objet, une capacité d’identification ex post des instruments innovants et une capacité ex ante d’innovation.Au terme d’une démarche de recherche-intervention, nous avons convenu de définir les instruments comme autant de chaînes de causalité préfigurées de l’action collective, et avons formulé un langage algorithmique autour d’un certain nombre d’éléments - des acteurs, des actions, des événements, des opérateurs logiques et des vecteurs d’impact – afin de les caractériser de façon ostensive. En consacrant une méthode d’évaluation de la nouveauté et de l’effectivité instrumentales, nous avons dès lors pu établir qu’un instrument est innovant s’il constitue une nouvelle chaîne de causalité opérant effectivement dans la réalité technico-sociale. De façon corollaire, innover un instrument revient alors à dessiner une nouvelle chaîne de causalité, ou à modifier les acteurs et les actions qui la composent.Afin d’illustrer et d’éprouver cette méthode de conception que nous qualifions de combinatoire, nous avons enfin cherché à interroger le caractère innovant du dispositif des certificats d’économie (CEE) et ce, en proposant un protocole d'évaluation et en formulant diverses pistes d'innovation. / Although it is diversely characterized, the innovative nature of instruments seems to follow three types of innovation: (a) imitations of existing instruments; (b) hybridizations of more or less coercive instruments; (c) or meta-conglomerations of instruments. After admitting that all instruments originate from one another through these three innovation paths and a unique object model, we tried to provide a new design method that would both enable the identification of innovative instruments and their design.Within the frame of intervention research, we agreed to define an instrument as a specific intended causal chain of public action, and formulated an algorithmic language along some instrumental elements (actors, actions, events, logical operators and impact vectors) in order to characterize instruments in an ostensive way. After developing a method to evaluate the newness and the effectivity of any instrument, we could more precisely define an innovative instrument as a new causal chain that is effectively implemented in the technical and social reality. As a corollary, innovating an instrument consists in designing a new causal chain, or modifying the actors and actions in it.Eventually, and in order to apply and test what we called a combinatory design method, we chose to question the innovative nature of the Energy Savings Certificates scheme (ESC). For this purpose, we elaborated an evaluation protocol and formulated several possible lines of innovation.

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