Évaluer la capacité de remplissage des cinq différentes techniques d’obturation canalaire dans l’obturation des canaux ovales. Matériel et méthodes : Un total de 220 molaires mandibulaires, avec 1 canal dans la racine distale, a été sélectionné. Chaque canal a été mise en forme jusqu’à la longueur de travail en utilisant un système mono-instrument le WaveOne Gold Primary Les dents préparées ont été divisées au hasard en cinq groupes égaux (n = 40 par groupe) pour l'obturation: condensation à onde continue (CWC), technique avec tuteur GuttaCore (GC), technique avec tuteur Thermafil (TH), technique utilisant un cône unique (SC), condensation hydraulique à froid (CHC). Les pourcentages de GPFA, SFA et VA ainsi que la présence des matériaux d’obturation à l’intérieur des tubulis dentinaires (tag)à longueur de travail (LT) -4mm et -2 mm a été évalué à par microscopie numérique optique, microscopie électronique à balayage (SEM) et microanalyse par rayons X à dispersion d'énergie (EDX). Analyse statistique : Les données collectées ont été analysées avec la version 11.2 de SigmaPlot (Systat Software, Inc., San José, CA, USA). Les pourcentages de GPFA, SFA, VA correspondant aux différentes groupes ont été comparés en utilisant le test de Kruskal-Wallis avec α=0,05. Résultats: à LT-4 et LT-2 mm, cette étude à montré une différence statistiquement significative en terme de capacité d’obturation pour le cinq techniques. À LT-4, les groupes GC et TH ont montré une différence statistiquement significative par rapport aux trois autres groupes en terme de GPFA et SFA. En terme de VA, il y a une différence statistiquement significative avec les groupes SC et CHC tandis qu’aucune différence n’a été démontrée entre les groupes GC , TH et CWC . À LT-2, les groupes GC et TH ont montré une différence statistiquement significative par rapport aux trois autres groupes en terme de GPFA, SFA, VA. Conclusion : 
Cette étude montre clairement que les obturations par GC et TH sont en mesure de remplir les canaux ovales d’une manière plus appropriée que les autres techniques d’obturation. 
Les groupes GC et TH, à LT -4 et -2mm, présentaient des tags de gutta-percha à l’intérieur des tubulis dentinaires. La présence de tags de gutta-percha à l’intérieur des tubulis dentinaires (à la place de tags de ciment beaucoup plus vulnérables) pourrait se comporter comme une barrière physique, capable de sceller les bactéries à l’intérieur des tubulis et surtout non résorbable dans le temps. / Assess the filling ability in oval-shaped canals using five different filling techniques. Materials and Methods : 220 human mandibular first molars with one distal oval canal were selected. Distal Canals were shaped using WaveOne Gold Primary. The prepared teeth were randomly divided in four equal groups (n = 40) for obturation : Continuous Wave Condensation (CWC), GuttaCore carrier based technique (GC), Thermafil (TH) carrier based technique, Single Cone technique (SC), Cold hydraulic Condensation (CHC). The proportions of gutta-percha filled areas (GPFA), sealer filled areas (SFA), void areas (VA) and the tags into dentinal tubules at 4 mm and 2 mm were analyzed by Optical numeric microscope, SEM and EDX. Statistical analysis : they were compared by Kruskal-Wallis one-way ANOVA on ranks, with statistical significance set at α = 0.05. Results : At 4 and 2 mm from the apex, this study discloses statistically different filling ability for the five techniques. At 4 mm from the apex, the GC et TH groups showed significantly higher PGFAs than lateral condensation and System B techniques. The GC et TH groups showed a statistically significance difference compared with the others three groups in terms of higher PGFA, lower SFA. It showed a statistically significance difference with SC and CHC groups in term of VA. At 2 mm level from the apex, the GC et TH groups showed a statistically significance differece compared with the others three groups in terms of higher PGFA, lower SFA and VA. Conclusions : GC obturation is able to fill oval-shaped canals in a more appropriate way than the other filling techniques. GC was the only group which showed the presence of gutta-tags at 4 and 2 mm from the apex. The gutta- percha tags could behave as a physical barrier able to entomb bacteria.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18855号 / 医博第3966号 / 新制||医||1007(附属図書館) / 31806 / 京都大学大学院医学研究科医学専攻 / (主査)教授 河野 憲二, 教授 黒田 知宏, 教授 富樫 かおり / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

The use of synthetic materials for tissue and organ reconstruction, i. e. tissue engineering, has become a promising alternative to current surgical therapies and may overcome the shortcomings of the methods in use today. The challenge is in the design and reproducible fabrication of biocompatible and bioresorbable polymers, with suitable surface chemistry, desirable mechanical properties, and the wanted degradation profile. These material properties can be achieved in various manners, including the synthesis of homo- and copolymers along with linear and star-shaped architectures. In many applications the materials’ three-dimensional structure is almost as important as its composition and porous scaffolds with high porosity and interconnected pores that facilitate the in-growth of cells and transportation of nutrients and metabolic waste is desired. In this work linear and star-shaped polymers have been synthesized by ring-opening polymerization using a stannous-based catalyst and a spirocyclic tin initiator. A series of linear copolymers with various combinations of 1,5-dioxepane-2-one (DXO), Llactide (LLA) and ε-caprolactone (CL) have been polymerized using stannous octoate as catalyst. It is shown that the composition of the polymers can be chosen in such a manner that the materials’ mechanical and thermal properties can be predetermined. A solvent-casting and particulate leaching scaffold preparation technique has been developed and used to create three-dimensional structures with interconnected pores. The achieved physical properties of these materials’ should facilitate their use in both soft and hard tissue regeneration. Well defined star-shaped polyesters have been synthesized using a spirocyclic tin initiator where L-lactide was chosen as a model system for the investigation of the polymerization kinetics. Neither the temperature nor the solvent affects the molecular weight or the molecular weight distribution of the star-shaped polymers, which all show a molecular weight distribution below 1.19 and a molecular weight determined by the initial monomer-to-initiator concentration. / QC 20101217

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Druckbauteile sind essentielle Elemente eines jeden Bauwerks, denn in Form von Stützen oder Wänden tragen sie die Lasten in den Baugrund ab. Heutzutage werden sie zumeist mit einem rechteckigen Querschnitt und konstanten Abmaßen über die Höhe ausgeführt. Bereits runde Stützen stellen eine Ausnahme dar und werden vor allem aus architektonischen Gründen angeordnet. Aber wie würde die möglichst optimale Geometrie eines Druckbauteils aussehen? Im Rahmen des Projekts wurde dieser zentralen Fragestellung nach einer günstigen Adaption der Querschnittsgeometrie von Stützen in Quer- und in Längsrichtung nachgegangen. Wesentliche Zielsetzung war dabei, Stützen so entwerfen und berechnen zu können, dass sie in allen Querschnittsbereichen gleichmäßig ausgelastet sind. Dadurch werden schlankere Bauteile möglich, die aufgrund der Materialersparnis nicht nur zur Schonung unserer natürlichen Ressourcen beitragen, sondern auch wirtschaftlich von Vorteil sind und zu einem ästhetischeren Erscheinungsbild führen. [Aus: Einleitung] / Pressure components are essential elements for any structure, because in the form of columns or walls they transfer the loads into the subsoil. Nowadays, they are usually designed with a constant rectangular cross-section over the full height. Already round columns are an exception and are arranged mainly for architectural reasons. But what would the optimum geometry of a pressure component look like? Within the framework of the project, this central question of a favourable adaptation of the cross-section geometry of columns in transverse and longitudinal direction was investigated. The main objective was to be able to design and calculate columns in such a way that they are equally loaded in all cross-section areas. This enables slimmer components which, due to the material savings, not only contribute to the conservation of our natural resources, but are also economically advantageous and lead to a more aesthetic appearance. [Off: Introduction]

Das Prinzip „Leicht Bauen mit Beton“ kann durch stabförmige Bauelemente außerordentlich gut umgesetzt werden, da einwirkende Beanspruchungen konzentriert und optimiert aufgenommen werden können. Stabförmige Bauelemente gehören zu den maßgebenden Bestandteilen von Mast- und Turmkonstruktionen sowie Fachwerk- und Rahmenstrukturen (Bild 1). Obgleich die Stäbe in diesen Konstruktionen überwiegend normalkraftbeansprucht sind, führen horizontale Beanspruchungen z. B. infolge Wind sowie Einspannungen in den Verbindungsknoten zu Biege- und Querkraftbeanspruchungen. Daneben sind nahezu alle räumlichen Konstruktionen durch einseitige oder unsymmetrische Beanspruchungen einer gewollten oder ungewollten Torsionsbeanspruchung unterworfen. [Aus: Einleitung] / The principles of “Concrete Light“ apply extraordinarily well to tubular concrete members, as applied stresses can be absorbed in a concentrated and optimized way. Tubular members are decisive components of mast and tower constructions as well as of truss and frame structures (Fig. 1). Although tubular members in such constructions are predominantly subjected to normal forces, horizontal loads (e.g. due to wind) and rigid joints lead to secondary bending moments and shear forces. In addition, as a result of one-sided or asymmetrical loads, almost all spatial constructions are subjected to intentional or unintentional torsion. [Off: Introduction]

Fast and accurate diagnosis is always in demand by modern medical professionals and in the area of national defense. At present, limitations of testing speed, sample conditions, and levels of precision exist under current technologies, which are usually slow and involve testing the specimen under laboratory conditions. Typically, these methods also involve several biochemical processing steps and subsequent detection of low energy luminescence or electrical changes, all of which reduce the speed of the test as well as limit the precision. In order to solve these problems and improve the sensing performance, this project proposes an innovative CMOS magnetic biological sensor system for rapidly testing the presence of potential pathogens and bioterrorism agents (zoonotic microorganisms) both in specimens and especially in the environment. The sensor uses an electromagnetic detection mechanism to measure changes in the number of microorganisms--tagged by iron nanoparticles--that are placed on the surface of an integrated circuit (IC) chip. Measured magnetic effects are transformed into electronic signals that count the number and type of organisms present. This biosensor introduces a novel design of a conical-shaped inductor, which achieves ultra-accuracy of sensing biological pathogens. The whole system is integrated on a single chip based on the fabrication process of IBM 180 nm (CMOS_IBM_7RF), which makes the sensor small-sized, portable, high speed, and low cost. The results of designing, simulating, and fabricating the sensor are reported in this dissertation. / Ph. D.

<p dir="ltr">The technological advancements in marine robotics led to the expansion of the autonomous underwater vehicle (AUV) fleet. Depending on the applications, the type of the AUV ranges across various shapes and sizes. It seeks a solution for the issue of limited power capacity, often in terms of underwater docking systems. Underwater docking poses a significant challenge for AUVs, especially when considering the diverse shapes and sizes of these vehicles. Existing solutions usually are task specific, and do not address the idea of scalable underwater docking system design.<br>This thesis investigates the adaptability of the specific docking system design, previously validated for torpedo-shaped AUVs, to boxed-shaped AUVs in a nonlinear open water environment. In order to achieve this goal, the scalability of the docking system design of choice was tested in an open water non-linear underwater environment and validated. The scalability of the robust docking system was adapted to the box-shaped AUV, encompassing path planning, path following, and docking maneuver. The adapted docking system was based on the optic methods for docking station detection and subsequent docking. Additionally, the simulated environment was developed for the AUV model, for testing and debugging purposes. In the simulation, a custom PID controller was developed along with integrating the navigation and guidance package, to fully simulate the real life behavior of the AUV. </p><p dir="ltr">Furthermore, this work introduces a recurrent neural network-based architecture for investigating temporal dependencies of the sequential data input. The proposed architecture is based on CNN for spatial feature extraction and LSTM/GRU for temporal feature detection. The dataset collection is based on the simulation environment, by enhancing the artificial images with imposed realism. The dataset was gathered on different levels of turbidity and the collection process was automated.</p>