Made available in DSpace on 2014-06-11T19:32:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-05Bitstream added on 2014-06-13T21:04:26Z : No. of bitstreams: 1 desantis_e_dr_araca.pdf: 2787266 bytes, checksum: b11c83dbba262a0641d23d2d0ceb74da (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivo: avaliar a regeneração da crista óssea alveolar e o processo de osseointegração de implantes instalados em sítios enxertados com blocos de osso autógeno e osso bovino mineral (DBBM),associado a membrana de colágeno. Material e método: em 6 cães labradores foram extraidos os molares inferiores bilateralmente, nos quais foi removida a tábua óssea vestibular, criando-se um defeito em formato de caixa. Após 3 meses de regeneração, os retalhos foram elevados e posicionado um guia com uma lima endodôntica, com a finalidade de alinhar paralelamente à parede vestibular do defeito. O guia foi removido e, no lado direito inferior (grupo controle), foi obtido um enxerto ósseo do ramo ascendente da mandibula, que foi fixado a parede lateral do defeito por meio de parafusos. No lado esquerdo inferior (grupo teste), foi fixado um bloco de DBBM no defeito mandibular. Em ambos os lados, os blocos enxertados foram protegidos por uma membrana de colágeno reabsorvível. Em seguida os retalhos foram suturados. Após elevação do retalho, utilizou-se o guia para instalação de um implante de cada lado da mandíbula, entre o enxerto e o osso remanescente. Após 3 meses, os animais foram eutanasiados para obtenção das peças a serem processadas laboratorialmente para análise histológica. Resultados: Todos os implantes apresentaram-se clinicamente estáveis. A espessura da crista alveolar no grupo teste foi de 5.4, 9.4 e 9.3 mm, antes, imediatamente após a enxertia, e no momento da instalação dos implantes respectivamente. No grupo controle (enxerto ósseo autógeno), a espessura da crista alveolar foi de 5.2, 9.0 mm antes e imediatamente após o procedimento de enxertia (reconstrução). Após 3 meses... / Aim: - to evaluate the healing of the alveolar bony crest and the integration of implants installed in augmented sites with autologous bone or DBBM blocks, concomitantly with a collagen membrane. Material & methods: Mandibular molars were extracted bilaterally in 6 Labrador dogs, the buccal bony wall was removed and a box-shaped defect was created. After 3 months, flaps were elevated and a device was applied to a stent and used for the placement of an endodontic file that was lined up parallel to the buccal wall of the defect. The stent was removed and, in the right mandibular side, a bony graft was harvested from the ascending ramus and secured to the lateral wall of the defect by means of screws. In the left mandibular side, a DBBM block was fixed to the defect. A resorbable membrane was applied both sides. The flaps were sutured. After three months, one bone graft was exposed, and the dog was excluded from further analysis. After flap elevation, the stent and the device were used as guide to install one implant in each mandibular side, between the graft and the parent bone. After 3 months, biopsies were harvested and ground sections prepared for histological evaluation. Results: All implants were clinically stable. The width of the alveolar crest at the test sites was 5.4mm before, 9.4mm immediately after grafting, and 9.3mm at implant installation. At the control sites (autologous bone graft), the width of the alveolar crest was 5.2mm before and 9.0mm immediately after the grafting procedure. After 3 months of healing, the width was 8.7mm. One autologous bone block graft was lost before implant installation. All implants installed were available for histological evaluation (n=5). The autologous bone... (Complete abstract click electronic access below)

Solid porous materials are network materials that contain space void. Porous Organic Polymers (POPs) are porous materials, which are constructed from organic building blocks and exhibit large surface area with low densities. Due to these characteristics, POPs have attracted attentions because of their potential use in application such as gas storage and chemical separation. This thesis presents a study of the synthesis of novel POP being a network based on 2,5- dibromobenzaldehyde and 1,3,5-triethynylbenzene linked together via Sonogashira- Hagihara (SH) coupling. This network showed a relatively good surface area of 770 m2/g and total pore volume of 0.59 cc/g. In addition, it proved to be chemically and thermally stable, maintaining the thermal stability up to 350oC. In addition to synthesize novel aldehyde-POP network, it was also possible to post synthetically modify a network via one-step post synthetic functionalization by amine. Ethelynediamine (EDA), Diethylenetriamine (DETA), and Tris(2-aminoethyl)amine (Tris-amine) are three different amines used for aldehyde-POP functionalization. The produced networks were aminated via different amine species substitution the aldehyde group present within the network. Modification to these networks resulted in a decrease in surface area from 770 m2.g-1 to 333 m2.g-1, 162 m2.g-1, and 211 m2.g-1 in respective to EDA, DETA, and Tris-amine. Although the surface areas were decreased, the CO2 adsorption was enhanced as evidenced by the increase of Qst (i.e., from 25 to 45 kJ.mol-1 for DETA at low coverage). Our findings are expected to strengthen existing research areas of the influence of different type of amines (e.g aromatic amine) on CO2 adsorption. Although amine grafting has been studied in other systems (e.g., PAFs and MOFs), we are the first to reported amine functionalized POPs using a novel one-step amine grafting PSM procedure. Future research might extend to study the interaction between CO2 and amine species under real working conditions.

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Yes / The changes induced by γ-ray pre-irradiated grafting of polytetrafluoroethylene (PTFE) with alkalo-amines such as Monoethanolamine (MEA), Diethanolamine (DEA) and Methyldiethanolamine (MDEA) solvents were investigated. Samples of the commercially available fluoropolymer, i.e. PTFE film membranes were irradiated with 60Co source γ-radiation with absorbed doses of 30 to 90 kGy. Effects of the grafting conditions of the amines onto the pre-irradiated PTFE, such as grafting time, reaction temperature and pre-irradiation doses on the resulting grafting yield are reported. The grafted PTFE was characterized by the FT-IR spectroscopy and FESEM.The gravimeteric analysis showed that the maximum grafting yield obtained is 2.9% for the 30 kGy irradiated MDEA grafted PTFE (MDEA-g-PTFE) at 10 min grafting time. However, at 60 min grafting time the maximum grafting yield reduced to 1.05% for the same sample. Consequently, therefore, for the low dose γ-ray pre-irradiated samples, the effects of applied dose and grafting time were found to be remarkably insignificant.

In conclusion, the present study firstly addressed the relationship between graft incorporation and peri-graft bone quality and quantity after ACL reconstruction in a rabbit model. The findings suggested that the non-invasive measurement of peri-graft bone would be useful to predict graft incorporation. Peri-graft bone loss was region-specific after surgery, which might be associated with stress shielding in the specific region after tunnel creation. The use of Brushite CPC might be a promising way to augment peri-graft bone and enhance graft incorporation. (Abstract shortened by UMI.) / In the fourth part, brushite CPC was successfully applied to augment the peri-tendon bone volume and connectivity. It was revealed under mechanical testing that the ultimate strength and stiffness of graft fixation in bone tunnel on experimental side was higher than that of the control by 117% and 102% respectively at 6 weeks, postoperatively (p<0.05 for both). The use of brushite CPC caused a paradigm shift in failure mode from intra-tunnel to intra-articular portion at 12 weeks postoperatively (p=0.013). / Keywords. anterior cruciate ligament reconstruction, bone mass, microarchitecture, tendon-to-bone healing, graft incorporation, brushite calcium phosphate cement / The first part of this thesis compared the histological characteristics of T-B healing interface tissue in femoral and tibial tunnels following ACL reconstruction in rabbits. Results revealed that less cartilaginous interface tissue was formed in tibial tunnel than in femoral tunnel. Such cartilaginous tissue was gradually mineralized during reestablishment of a direct T-B integration. T-B healing in tibial tunnel was inferior to that in femoral tunnel. The disparity of T-B healing in various osseous milieus suggested the potential association in between. / The second part of this original work further explored the numeric relationship between the strength of T-B attachment and peri-graft bone mass and connectivity. Results of Micro-computed tomography (micro-CT) showed that peri-graft bone mass and connectivity was significantly lower on tibial side than those on femoral side. It was found under biomechanical evaluation that grafted tendon was prone to be pulled out from tibial tunnel with the bone attachment; the weakest point of the complexes shifted from the healing interface at time zero to peri-graft bone at week 6 after operation. With reverse of peri-graft bone at week 12 postoperatively, the weakest point shifted to intra-osseous tendinous portion. The stiffness of graft fixation correlated with peri-graft BV/TV (r2=0.68, p=0.001) and connectivity (r2=0.47, p=0.013) at week 6 after operation. / The third part addressed the changes of peri-graft bone in spatial and temporal manners using high resoluation multiple-slice peripheral quantitative computed tomography (pQCT) and micro-CT. Under pQCT evaluation, a decrease in BMD was present in specific regions, medial region of femoral tunnel by 26% and posterior and lateral regions of tibial tunnel by 22% and 42%, respectively at week 12 postoperatively than the baseline (p<0.05 for all). It was accompanied by a decrease in trabecular number and increase in trabecular spacing, the shift of plate-like to rod-like trabeculae and loss of anisotropy under micro-CT evaluation. It was echoed by histological findings showing increased osteoclastic activities and poor T-B healing in these specific regions. The postoperative bone loss and associated poor T-B healing was region-specific. / by Wen, Chunyi. / Adviser: Kai-ming Chan. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0217. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 148-168). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

Orientador: Heloise de Oliveira Pastore / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T16:48:58Z (GMT). No. of bitstreams: 1 Moura_HipassiaMarcondesde_M.pdf: 6781457 bytes, checksum: b05858e45bf4d0bdf564a43406440fc9 (MD5) Previous issue date: 2013 / Resumo: O estudo da inserção de alumínio na estrutura lamelar da magadiita assim como o acompanhamento de sua cristalização permitiu elucidar os mecanismos de incorporação deste metal neste tipo de silicato, ainda pouco investigado na literatura. Através do monitoramento por técnicas espectroscópicas (RMN de Si e Al, IV-TF e XPS) e não espectroscópicas (DRX, análise elementar e TGA) das etapas de formação da [Al]-magadiita, notou-se que sua obtenção em laboratório pode ser otimizada devido ao uso de sementes do próprio material. Os experimentos de XPS elucidam a [Al]-magadiita como uma estrutura do tipo `coreshell¿, constituída de magadiita silícica sobre a qual encontra-se depositada uma camada de aluminossilicato. Seguido por estudos de adsorção de CO à baixas temperaturas, avaliou-se os sítios ácidos dos materiais obtidos pelo uso de sementes de cristalização assim como a homogeneidade da distribuição da camada de aluminossilicato. A [Al]-magadiita pode apresentar aplicações descritas na literatura como precursora de outras estruturas zeolíticas. Porém, pouco se explora seu uso em outros tipos de modificações como é feita para sua forma livre de alumínio, a magadiita. Nesse sentido, algumas modificações na superfície do aluminossilicato foram investigadas. Dentre elas, a organossililação ("grafting") com grupos aminopropil (APTS), a pilarização com tetraetilortosilicato (TEOS) e a modificação com ambas as fontes de silício, permitindo a formação de novos materiais mesoporosos e/ou funcionalizados contendo alumínio em sua rede cristalina e grupos orgânicos ativos na captura de gases ácidos como o carbônico. / Abstract: The synthesis of [Al]-magadiite was monitored during preparation and crystallization by the Aluminum-Induced Crystallization method developed previously. A systematic study of the physicochemical and thermal properties of the products obtained at each step in [Al]-magadiite synthesis was performed by combining different experimental techniques [infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and solid-state magic-angle spinning nuclear magnetic resonance (MAS-NMR)]. The results obtained showed that the hydrothermal treatment before aluminum insertion served essentially for the creation of magadiite seeds. Thus, induced crystallization by introduction of magadiite seeds directly in the synthesis gel showed that the synthesis duration could be reduced into a single step. XPS spectroscopy allowed designing the [Al]- magadiite structure as a pure silicon magadiite core with a thin layer of aluminosilicate deposited on top of it. Using the CO adsorption at low temperature with IR-FT, the acid sites of the SIC-[Al]-magadiites were evaluated as the aluminosilicate shell distribution over the magadiite crystal. [Al]-magadiite found applications described in the literature as a precursor to other zeolites structures. However, little is explored about its use in other types of surface modifications such as done for its aluminum free form, magadiite. In this sense, some modifications on the aluminosilicate surface were investigated. Among them, the grafting with aminopropyl groups (APTS), the pillaring with tetraethylorthosilicate (TEOS) and the modification with both silicon sources, allowing the formation of novel mesoporous and/or functionalized materials containing aluminum in its crystalline lamella and active organic groups in acid gases uptake such as carbon dioxide. / Mestrado / Quimica Inorganica / Mestra em Química

Le but de ce projet a été d'améliorer un procédé de clarification développé par VEOLIA Environnement : l'Actiflo®. L'Actfilo® est basé sur l'ajout de microsable lors de l'étape de floculation afin d'augmenter les vitesses de décantation. Toutefois, une importante quantité de polymère est continuellement ajoutée au procédé, et des résiduels de ce dernier peuvent être rencontrés dans les eaux décantées. Notre travail a été de fonctionnaliser (i.e. greffer) le microsable avec un polymère floculant afin de pouvoir recycler en continu le matériau hybride par hydrocyclonage. La fonctionnalisation par « Grafting Onto » a consisté à greffer un polymère floculant commercial sur le microsable alors que la fonctionnalisation par « Grafting From » a consisté à faire croître un polymère floculant depuis la surface. Les capacités floculantes des microsables ont été testées en essais classiques de coagulation/floculation. Les microsables fonctionnalisés avec un polymère cationique par « Grafting From » ont démontré leur supériorité en conduisant à un abattement en Carbone Organique Dissous (COD) de 25% contre un abattement de 15 % pour le procédé classique ou pour les microsables fonctionnalisés par « Grafting Onto ». Une turbidité légèrement supérieure est toutefois toujours obtenue avec les sables fonctionnalisés par rapport à l'ajout de polymère libre (+ 0,5 NTU). Enfin, des procédés de régénération permettant de réutiliser les microsables ayant servi en coagulation/floculation ont été mis en place, le plus efficace d'entre eux étant un traitement à base d'Acide Oxalique. Ce traitement a permis de régénérer les propriétés floculantes du sable sur deux cycles. / The purpose of this project was to improve a clarification process developed by VEOLIA Environment: The Actiflo®. The Actfilo® is based on adding microsand in the flocculation stage in order to increase the speed of sedimentation. However, a significant amount of polymeric flocculant is continuously added to the process, and residuals can be found in the decanted water. Our work was to graft a polymeric flocculant onto microsand in order to recycle the full hybrid material through hydrocycloning. Functionalization by "Grafting Onto" was based on grafting a commercial polymer onto microsand whereas “Grafting From” was based on surface-initiated polymerization. Flocculation properties of functionalized microsands were then tested in conventional coagulation/flocculation tests where the effectiveness of the two grafting methods was compared. Cationic functionalized sands, obtained by “Grafting From”, exhibit the best properties as a decrease of Dissolved Organic Carbon of 25% was reached whereas a decrease of 15% was reached by adding free polymer or adding sands from the “Grafting Onto” method. However final turbidity value was always slightly lower for the flocculation that occured when free polymer was added (- 0,5 NTU). Finally, regeneration processes to recycle the functionalized sands were established. The most effective of them being a treatment with Oxalic Acid. This treatment allowed us to regenerate flocculating properties of functionalized sands twice.

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published_or_final_version / Anatomy / Doctoral / Doctor of Philosophy