Texte remanié de: Diss.--Fakultät Philosophie--Stuttgart--Universität, 2000. / Bibliogr. p. 238-263.

This creative project illustrated the painting process used to execute a Super Realistic Style painting. The background information that was covered in the paper explored the essence of the Super Realistic movement. The end product of this creative project was a Super Realistic painting and a series of slides that illustrated the painting process from beginning to end.

La régénération tissulaire guidée et la régénération osseuse guidée sont des interventions chirurgicales visant la régénération des tissus perdus du parodonte et de l’os alveolaire. Dans ces techniques, une membrane biocompatible est implantée autour de la lésion intra osseuse parodontale, remplie ou non d'une greffe osseuse, afin de prévenir sa colonisation par les tissus mous. L'hydroxypropyl méthylcellulose silanisée (Si-HPMC) est un hydrogel auto-réticulant qui peut être injecté sous forme de solution visqueuse puis, grâce à la réaction de condensation, construire un réseau 3D. Il a été démontré que le Si-HPMC réticulé agissait comme barrière physique contre l'invasion des tissus mous dans les défauts parodontaux chez le chien. Le principal inconvénient de cet hydrogel auto-réticulant est une cinétique de réticulation trop lente pour des applications cliniques optimales. L'objectif principal de cette thèse était donc le développement et la caracterisation de deux resaux interpenetres d’hydrogels (IPNs) composé de Si-HPMC et d’un polysaccharide : soit le carboxyméthyl chitosane (CMCS), soit le dextrane Nous avons greffé sur le CMCS et le dextrane des groupes méthacrylate capables de réagir sous irradiation d'une lampe à photopolymériser standard utilisée en dentisterie en présence d’un photo-initiateur composé de vitamine B2. Les polymères ont été synthétisés et caractérisés avec succès. Deux IPNs innovants ont été réalisés et les propriétés chimiques et physico-chimiques ont été étudiées. De plus, des études in vitro et in vivo ont été réalisées pour évaluer la cytocompatibilité et pour étudier l'aptitude de ces deux membranes innovantes hydrogel IPN à promouvoir la régénération tissulaire ou osseuse guidée. Les résultats sont encourageants et nécessitent d'autres investigations in vivo pour caractériser les biomatériaux et confirmer leur potentiel en tant que biomatériaux dentaires et implantaire. / Guided tissue regeneration and guided bone regeneration are surgical procedures aiming the regeneration of lost components of periodontium. In these techniques a periodontal intraosseous defect is filled or not with a bone graft material and covered with a biocompatible membrane in order to prevent its colonization by soft tissues. In fact, during a physiological healing, it appears that the soft tissue migrates rapidly into the wound, avoiding the regeneration. The barrier membrane plays a key role to prevent undesirable tissue migration into the defective area, and consequently, it allows sufficient time for bone, cementum, and periodontal ligament regeneration. Silanized hydroxypropylmethyl cellulose (Si-HPMC) is a self-setting hydrogel that can be injected in vivo as a viscous solution and then, due to the condensation reaction, build a 3D network. It has been demonstrated demonstrated that cross-linked Si- HPMC acted as a physical barrier against soft tissue invasion in periodontal defects in dogs. The main drawback of this self-setting hydrogel is the too slow crosslinking process, which is not suitable for clinical needs. Nevertheless, the results were quite promising due to the easy preparation and handling of polymer solution, which could lead to simplified periodontal treatment. Therefore, the main objective of this thesis was the development and the characterization of two injectable interpenetrating polymer network hydrogels (IPNs) composed of Si-HPMC and two polysaccharides: carboxymethyl chitosan (CMCS) or dextran. We grafted on CMCS and dextran methacrylate groups able to react under irradiation of standard photopolymerization dentistry lamp. We selected vitamin B2 as a photoinitiator. The polymers were successfully synthetized and characterized. Two innovative IPNs were realized and the chemical and physico-chemical properties were studied. In addition, in vitro, in vivo study were performed to assess the cytompatibility and to study the suitability of these two innovative IPNs hydrogel membrane for guided tissue or bone regeneration. The encouraging results need in vivo further investigations to characterize the biomaterials and confirm the potentiality as dental biomaterials.

No description available.

No description available.

La société ESSILOR est à l’origine d’un nouveau concept ophtalmique : « l’optique digitale ». Ce concept s’appuie sur la discrétisation du verre en pixels et l’introduction, dans ces structures micrométriques, de liquides fonctionnels. Les axes de recherche de cette thèse sont issus des besoins et contraintes de cette thématique et ils concernent principalement : l’élaboration de couches minces polymères par un procédé CVD (Chemical Vapor Deposition) et les dépôts de films sur des substrats liquides. Un bâti commercial de CVD avec un mode d’activation thermique a permis la réalisation contrôlée et la caractérisation de couches minces conformes d’un matériau polymère aux propriétés en adéquation avec le cahier des charges industriel : le parylène. Des études sur le mécanisme mis en jeu ont révélé un mode de croissance original de ce matériau et pouvant être décrit par différents modèles complémentaires dans les informations qu’ils apportent. Nous avons également imaginé un dispositif de modulation des propriétés surfaciques des films de parylène par une fonctionnalisation en voie sèche. Le second procédé CVD qui a été étudié met en œuvre l’activation photonique. Il s’agit d’un bâti de photo-CVD innovant et très modulable, développé au CIRIMAT, pour répondre au mieux aux besoins de ce projet « verre digital » et en particulier à la nécessité de déposer des couches de divers polymères sur des liquides fonctionnels à une pression se rapprochant de la pression atmosphérique. / ESSILOR society is investigating a new ophthalmologic concept: “the digital optic”. This concept is based on the discretization of the ocular glass in pixels, and the insertion, in those micrometric structures, of functional liquids. The research work of this PhD thesis aims to satisfy the requirements and constraints of this topic. They principally concerns: the elaboration of thin polymeric films by a CVD (Chemical Vapor Deposition) process and the deposition on liquid substrates. A commercial CVD reactor thermally activated has permitted the controlled production and the characterization of conform polymeric thin films whose properties are in good adequacy with the industrial specifications: the parylene. Studies on the mechanism have revealed an original growth mechanism of this material which can be described with some complementary and informative models. We also have developed a functionalization method by a dry process to modulate the surface properties of parylene films. The second CVD process studied uses a photonic activation. It is an innovative and very flexible photo-CVD process designed in the CIRIMAT in order to satisfy the “digital glass” project and in particular the necessity to deposit various polymer films on functional liquids at a pressure near the atmospheric pressure.

Tese de mestrado. Multimédia (Perfil Tecnologias). Universidade do Porto. Faculdade de Engenharia. 2011

Photo of the Guardalavaca market place in Cuba taken by second year Communication student Samantha Essai.

This work presents a novel loss-reduced photonic liquid-crystal fiber (PLCF) using the non-contact photo-alignment method. The photo-excited and adsorbed azo dye on the capillary surface of a PLCF induces uniform and highly ordered orientation of the LC. The anchoring force of the photo-alignment effect is combined with that generated by surface boundary conditions of the photonic crystal fiber (PCF). Transmission loss resulting from LC scattering can be reduced from -2.8db/cm to -1.3db/cm within 10min. This photo-induced alignment yields a permanent boundary for the LC in the PCF that reduces scattering loss, and can be further modulated by electrical fields. The electrical tunable effect and fast dynamic response of the photo-aligned PLCF are also presented. This low-loss PLCF can be applied conveniently in various PLCF devices.

Photo-polymerized cross-linked polyacrylamide gels are becoming increasingly important for use in micro-fabricated DNA electrophoresis systems because they allow a concentrated sieving matrix to be precisely positioned at any location within a complex micro-channel network. The rate of photo-initiation in the free radical gel polymerization reaction, however, can exert a strong influence on the resulting gel structure. Experimental data on separation resolution of single stranded DNA (ssDNA) in photoinitiated polyacrylamide gels is very sparse. In this study, we investigate the performance of ssDNA electrophoresis in an ALF Express automated DNA sequencer using various photo-initiation chemistries. Cross-linked polyacrylamide gels with concentrations ranging from 6 to 12 %T were prepared using riboflavin, methylene blue, irgacure 651 and ReproGel (AP Biotech) photo-initiators. Separation resolution is compared with that attained in cross-linked polyacrylamide gels prepared using conventional chemical initiators (e.g. ammonium persulfate/ Tetramethylethylenediamine) in order to determine the polymerization conditions necessary for optimum performance.