Chung, Shu Lu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 109-118). / Abstracts in English and Chinese. / Abstract --- p.i-iv / 中文摘要 --- p.v-vii / Publications --- p.viii / Acknowledgements --- p.ix / List of Abbreviations --- p.x-xi / Index for Figures --- p.xii-xiv / Index for Tables --- p.xv / Table of Contents --- p.xvi-xix / Chapter Session 1: --- Introduction --- p.1 / Chapter 1.1 --- Biology of fracture healing process --- p.2 / Chapter 1.1.1 --- Stage of inflammation --- p.2-3 / Chapter 1.1.2 --- Stage of soft callus formation --- p.3-4 / Chapter 1.1.3 --- Stage of hard callus formation --- p.4-5 / Chapter 1.1.4 --- Stage of bone remodeling --- p.5 / Chapter 1.2 --- Conventional treatments and its limitations --- p.5-6 / Chapter 1.3 --- Biological treatments in accelerating fracture healing process --- p.6-7 / Chapter 1.4 --- Biophysical treatments in accelerating fracture healing process --- p.7-8 / Chapter 1.4.1 --- Electromagnetic fields --- p.8-9 / Chapter 1.4.2 --- Shockwave --- p.9 / Chapter 1.4.3 --- Low intensity pulsed ultrasound --- p.9-11 / Chapter 1.5 --- Properties of ultrasound --- p.11 / Chapter 1.5.1 --- Ultrasound signals --- p.11-12 / Chapter 1.5.2 --- Attenuation of ultrasound --- p.12-14 / Chapter 1.5.3 --- Modes of ultrasound wave propagation --- p.14-15 / Chapter 1.5.4 --- Reflection and critical angle --- p.15-18 / Chapter 1.6 --- Insights from previous studies --- p.18-19 / Chapter 1.7 --- Hypothesis --- p.19 / Chapter 1.8 --- Study plan --- p.20 / Chapter 1.9 --- Objectives --- p.20 / Chapter Session 2: --- Materials and Methodology --- p.25 / Chapter 2.1 --- Materials --- p.26 / Chapter 2.2. --- Closed femoral fracture rat model --- p.26 / Chapter 2.2.1 --- Operation procedures --- p.26-27 / Chapter 2.3 --- Groupings --- p.27 / Chapter 2.4 --- Low Iintensity Pulsed Ultrasound treatment --- p.28 / Chapter 2.4.1 --- Incident angles determination --- p.28 / Chapter 2.4.2 --- LIPUS devices --- p.29 / Chapter 2.4.2 --- Set up of standardized platform --- p.29-30 / Chapter 2.4.4 --- Treatment procedure --- p.30 / Chapter 2.5 --- Radiographic analysis --- p.31 / Chapter 2.6 --- Micro-Computed Tomography --- p.32 / Chapter 2.6.1 --- Micro-Computed Tomography scanning --- p.32 / Chapter 2.6.2 --- Micro-Computed Tomography analysis --- p.32-33 / Chapter 2.7 --- Histology --- p.34 / Chapter 2.7.1 --- Sample preparation --- p.34 / Chapter 2.7.2 --- Histomorphometrical analysis --- p.34-35 / Chapter 2.8 --- Mechanical Testing --- p.35 / Chapter 2.9 --- Statistical analysis --- p.35 / Chapter Session 3: --- Results --- p.48 / Chapter 3.1 --- Radiographic analysis --- p.49 / Chapter 3.1.1 --- Qualitative analysis - Callus bridging rate --- p.49 / Chapter 3.1.2 --- Quantitative analysis - Callus area and callus width --- p.49-50 / Chapter 3.2 --- Micro-computed tomography analysis --- p.50 / Chapter 3.2.1 --- Qualitative analysis - 3D reconstructed images --- p.50-51 / Chapter 3.2.2 --- Quantitative analysis - Bone volume of callus --- p.51 / Chapter 3.2.3 --- Quantitative analysis - Bone mineral density and bone mineral content --- p.51-52 / Chapter 3.3 --- Biomechanical test --- p.52-53 / Chapter 3.4 --- Histomorphological analysis --- p.53 / Chapter 3.4.1 --- Qualitative analysis --- p.53 / Chapter 3.4.2 --- Quantitative analysis --- p.53-54 / Chapter Session 4: --- Discussion --- p.85-87 / Chapter 4.1 --- Enhancement effects of LIPUS at different incident angles --- p.88 / Chapter 4.1.1 --- LIPUS transmitted at 350 accelerated the fracture healing process --- p.88 / Chapter 4.1.1.1 --- Callus bridging and callus mineralization --- p.88-89 / Chapter 4.1.1.2 --- Dose dependent effects of LIPUS -Maximization of ultrasound energy --- p.89-90 / Chapter 4.1.2 --- LIPUS transmitted at 35° enhanced the restoration of mechanical properties in fracture healing process --- p.90 / Chapter 4.1.2.1 --- Biomechanical properties --- p.90-91 / Chapter 4.1.2.2 --- Bone mineral density and bone mineral content --- p.91-92 / Chapter 4.1.2.3 --- Highly mineralized callus area and volume --- p.92-93 / Chapter 4.2 --- 35° may be the critical angle for further enhancing fracture healing --- p.93 / Chapter 4.2.1 --- LIPUS transmitted at 35° may be the first critical angle in this study --- p.93-95 / Chapter 4.2.2 --- Effects of different incident angles --- p.95-96 / Chapter 4.3 --- Mechanism of LIPUS at different incident angles on fracture healing process --- p.96 / Chapter 4.3.1 --- Endochondral ossification --- p.96-99 / Chapter 4.4 --- Advantages in using LIPUS transmitted at critical angle --- p.99 / Chapter 4.5 --- Limitations of the study --- p.100 / Chapter 4.5.1 --- Animal model --- p.100 / Chapter 4.5.2 --- Treatment sites of LIPUS transmitted at different incident angles --- p.100 / Chapter 4.5.3 --- Types of fracture --- p.101 / Chapter Session 5: --- Conclusions --- p.102-104 / Chapter Session 6: --- Future Studies --- p.105 / Chapter 6.1 --- Protocol and regime of LIPUS transmitted at different angles --- p.106 / Chapter 6.2 --- Periosteum-stripped fracture model --- p.106-107 / Chapter 6.3 --- Molecular mechanism of LIPUS transmitted at different incident angles --- p.107-108 / Bibliography --- p.109-118 / Appendix I --- p.119

Characterization of fractures in an arkosic sandstone from the western damage zone of the San Andreas Fault (SAF) at San Andreas Fault Observatory at Depth (SAFOD) was used to better understand the origin of damage and to determine the scale dependence of fracture fabric and fracture density. Samples for this study were acquired from core taken at approximately 2.6 km depth during Phase 1 drilling at SAFOD. Petrographic sections of samples were studied using an optical petrographic microscope equipped with a universal stage and digital imaging system, and a scanning electron microscope with cathodoluminescence (SEM-CL) imaging capability. Use of combined optical imaging and SEM-CL imaging was found to more successfully acquire true fracture density at the grain scale. Linear fracture density and fracture orientation were determined for transgranular fractures at the whole thin section scale, and intragranular fractures at the grain scale. The microscopic scale measurements were compared to measurements of mesoscopic scale fractures in the same core, as well as to published data from an ancient, exhumed trace of the SAF in southern California. Fracturing in the damage zone of the SAF fault follows simple scaling laws from the grain scale to the km scale. Fracture density distributions in the core from SAFOD are similar to distributions in damaged arkosic sandstone of the SAF along other traces. Transgranular fractures, which are dominantly shear fractures, indicate preferred orientation approximately parallel to the dominant sets of the mesoscale faults. Although additional work is necessary to confirm general applicability, the results of this work demonstrate that fracture density and orientation distribution over a broad range of scales can be determined from measurements at the mesoscopic scale using empirical scaling relations.

Reproduction de : Thèse d'exercice : Médecine : Nancy 1 : 2003. / Titre provenant de l'écran-titre.

published_or_final_version / Orthopaedic Surgery / Master / Master of Philosophy

Thesis (Ph. D.)--University of Lund, 1995. / Published dissertation.

Thesis (Ph. D.)--University of Lund, 1995. / Published dissertation.

Thesis (M.S.)--University of Missouri-Columbia, 2006. / "August 2006" The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. Includes bibliographical references.

Orientador: Simonides Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-23T15:57:19Z (GMT). No. of bitstreams: 1 CelegattiFilho_TorideSebastiao_M.pdf: 4195192 bytes, checksum: e279d02d5c5aabef9927997e90717129 (MD5) Previous issue date: 2013 / Resumo: O propósito neste estudo foi desenvolver placas em forma de Y com espessuras de 0,6, 1,0 e 1,5 mm para ser usadas em fratura de colo de côndilo da mandíbula e submetê-las ao ensaio de resistência mecânica de compressão. Fo-ram desenvolvidas 10 placas em Y para cada espessura, contendo 8 furos. As placas foram confeccionadas de acordo com projeto idealizado pelo autor e fabricado pela empresa Toride Indústria e Comércio Ltda., Mogi Mirim, SP, Brasil. As placas foram confeccionadas com titânio comercialmente puro (grau ll), conforme norma ASTM F-67. Os processos para desenvolvimento das placas foram feitos em programa de desenho mecânico Solid Works. A confecção das placas seguiu a metodologia de fabricação já existente na empresa, compreendendo processo de usinagem em equipamento modelo Discovery Romi de 4 eixos, o qual mantém precisão e controle dimensional com tolerância de ± 0,10 mm. Foram também confeccionadas 30 hemi-mandíbulas do lado esquerdo, com resina de poliuretano rígido de densidade 40 a 50 PCF onde as placas foram fixadas para conter fratura simulada da cabeça do côndilo. O teste de carregamento foi executado na máquina para ensaio universal Instron, modelo 4411, aplicando carga na posição médio-lateral e ântero-posterior na cabeça do côndilo. ANOVA com 2 fatores e teste de Tukey com 5% de significância foram aplicados nos resultados. Quando a carga foi aplicada no sentido médio-lateral, a placa de maior espessura (1,5 mm) obteve a maior resistência, mas sem diferença estatística entre os deslocamentos de 5,0 e 10,0 mm. No sentido ântero-posterior, a placa com maior resistência foi a de menor espessura, seguida pela de maior espessura. Pode-se concluir que: 1 - No sentido médio-lateral, os maiores valores de resistência foram observados no deslocamento de 15 mm, exceto para as placas 0,6 e 1,5 mm com valores similares em 10 e 20 mm respectivamente; 2 - A placa com espessura de 1,5 mm foi a única que apresentou maior valor médio em todos os deslocamentos; 3 - No sentido ântero-posterior, os maiores valores de resistência foram vistos no deslocamento de 15 mm e os menores em 5 mm para todas as espessuras de placas; 4 - A placa com espessura de 0,6 mm foi a que apresentou maiores valores em todos os deslocamentos e 5 - No sentido ântero-posterior, o carregamento de 20 mm não foi alcançado / Abstract: The purpose of this study was to develop a Y plate with thicknesses of 0.6, 1.0 and 1.5 mm for use in condylar mandible fracture and submit them to the me-chanical strength testing Compression. For this study 30 plates were used for surgical containment internal, Y geometry and holes 8, 10 plates with a thickness of 0.6 10 mm plates with 1.0 mm thickness and 10 plates with thickness of 1.5 mm. This model plate was designed by the author and manufactured by Toride Industry e Comercio Ltda., Mogi Mirim, Brazil. The plates were made from commercially pure titanium (grade II), according to ASTM F-67. The processes for developing the plates were made in program Solid Works mechanical design engineering company by Toride, following the procedures of the project. The making of the plates followed the methodology in an existing manufacturing company, including process equipment machining model Romi Discovery of 04 axes, which keeps ac-curacy and dimensional control with a tolerance of ± 0.10 mm, required by the quality system of the company Toride. Were prepared hemi-jaws 30 on the left side with hard polyurethane resin density 40-50 PCF where the plates were fixed. The load test was run on the test equipment universal Servohidráulico Instron Model 4411 (Instron Corp., Norwood, MA.), and will have to evaluate the strength of plates attached Hemi-mandibles applying the force in mid-lateral position, and the force applied at Antero-posterior position, were predetermined three shifts, ob-taining values of average load in the three, Statistical analysis of variance by ANOVA used 02 factors, the Tukey test at 5% significance level was applied. When the load was applied in the medial-lateral plate of greater thickness (1.5 mm) gave the highest strength, but no statistical difference in displacement of 5.0 and 10.0 mm. Antero-posterior direction on the plate was the biggest strength of thinner, following the greater thickness. It can be concluded that: 1 - In the medial - lateral direction, the highest values of resistance were observed in the displacement of 15 mm, except for the 0.6 and 1.5 mm plates with similar values in 10 and 20 mm respectively; 2 - A plate with thickness of 1.5 mm was the one with the highest average value on all shifts; 3 - In the antero-posterior direction, the highest values of resistance were seen in the displacement of 15 mm and 5 mm in the minors for all thicknesses of plates; 4 - A plate with thickness of 0.6 mm showed the highest values in all shifts and; 5 - In the antero-posterior direction, the loading of 20 mm was not achieved / Mestrado / Materiais Dentarios / Mestre em Materiais Dentários

Les réservoirs géologiques fracturés ont une place importante parmi les défis environnementaux et économiques du 21e siècle. En effet, ils sont associés tantôt au stockage de fluides en profondeur comme les déchets nucléaires, tantôt à la production de ressources fondamentales pour nos sociétés comme l'énergie géothermique. Les écoulements préférentiels au sein des roches fracturées sont façonnés par des réseaux de fractures qui rendent le milieu très hétérogène et anisotrope, et dont la structure et les propriétés physiques sont difficiles à déterminer, car elles dépendent notamment de l'échelle d'investigation et de la connectivité des réseaux. Dans cette thèse, nous évaluons le potentiel informatif des méthodes de déformations de surface, en particulier l'inclinométrie, pour suivre et décrire les réservoirs fracturés à trois échelles importantes. Les inclinaisons de la surface du sol, ou tilt, sont en effet très sensibles aux flux souterrains et par conséquent à l'impact des structures conductrices principales. Dans un premier temps, nous développons la stratégie méthodologique visant à interpréter les signaux inclinométriques. A l'aide d'un modèle élastique et à travers une exploration systématique de l'espace des paramètres géométriques, nous avons observé que le tilt est principalement sensible au pendage et à l'extension en profondeur d'une fracture, mais que cette sensibilité dépend de l'endroit où sont placés les instruments en surface. Nous validons ensuite l'approche hydrogéodésique en couplant un suivi temporel fin des déformations à l'aide d'inclinomètres longue-base, et une cartographie bien distribuée des déplacements verticaux par nivellement optique, au cours d'une mise en charge d'une zone de faille pendant quelques heures. Les observations sont honorées avec succès à l'aide d'un modèle hydromécanique simple permettant notamment d'estimer l'emmagasinement de la faille, en accord avec des études passées utilisant des méthodes différentes. Une modélisation poro-mécanique du problème de diffusion de pression au sein d'une zone de faille sub-verticale, incluse dans une matrice moins transmissive, a permis de démontrer que le signal transitoire de déformation en surface rend compte des propriétés mécaniques de la faille, ainsi que du fonctionnement hydromécanique du système dans son ensemble. Ensuite, nous avons développé une approche expérimentale permettant de suivre les déformations en surface associées à la mise en pression de fractures profondes et horizontales d'extension métrique. Grâce à la nature oscillatoire de la charge hydraulique imposée, nous avons pu identifier la signature des variations d'ouverture des fractures testées dans le signal d'un inclinomètre pendulaire. Les amplitudes trouvées, de l'ordre de 10 nanoradians pour quelques centimètres de charge hydraulique, permettent d'obtenir des estimations cohérentes de la raideur des fractures. Enfin, nous avons abordé la problématique des flux saisonniers au sein d'un aquifère de socle fracturé et son lien avec la recharge. Le signal inclinométrique est fortement corrélé aux variations piézométriques annuelles du site d'étude mais possède la singularité importante d'être en avance de phase d'environ un mois. Nous interprétons avec succès les chroniques inclinométriques à l'aide d'un modèle hydromécanique 1D, et mettons en valeur le fait que la méthode présente un intérêt pour déterminer la géométrie du réservoir à large échelle, et est sensible aux modalités de la recharge (diffuse versus focalisée, dans le temps et l'espace) davantage encore que ne l'est la piézométrie. Ce résultat inédit ouvre des perspectives quant à l'estimation des flux liés à la recharge, ce qui est un enjeu majeur pour les questions de gestion de ressource en eau. Nous concluons donc que l'inclinométrie est une méthode à fort potentiel pour décrire les propriétés et le comportement hydromécanique des réservoirs fracturés, de l'échelle du mètre jusqu'à plusieurs kilomètres. / Fractured geological reservoirs have an important position among the environmental and economical challenges of the 21st century. In fact, they are either associated to deep storage of fluids, like nuclear wastes and carbon dioxide, or to the production of resources that are fundamental in our society, like geothermal energy and water. Preferential flowpaths within fractured rocks are shaped by fracture networks which make the media very heterogeneous and anisotropic. It is difficult to determine their structure and physical properties as they actually depend on the network's connectivity and scale of investigation. In this thesis, we assess the informational potential of surface deformation methods, in particular surface tilt, to monitor and describe fractured reservoirs at three important scales. Indeed, surface tilt is very sensitive to deep sub-surface fluxes and thereby to the impact of main conductive structures. Firstly, we develop the methodological strategy aiming at interpreting surface tilt. Using an elastic model and through a systematic exploration of the geometrical parameter space, we observe that tilt measurements are mainly sensitive to a fault's dip and extension in the dip direction. However, this sensitivity clearly depends on the position of measurement with respect to the fault. In addition, we validate the hydrogeophysical approach by monitoring the deformation induced by the pressurization of a sub-vertical fault zone during a few hours, using continuous long-baseline tiltmeter data and spatially distributed vertical displacements from two optical leveling campaigns. The observations are successfully reproduced by a simple hydromechanical model from which we estimate the fault's storativity, in agreement with previous results obtained from different approaches. A more robust poro-mechanical model of pressure diffusion in a fault embedded in a less permeable matrix is then used to further investigate the information content of transient tilt data. Therewith, we show that surface tilt is sensitive to the mechanical properties of the fault zone and to the hydromechanical functioning of the system as a whole. Secondly, we have developed an experimental approach aiming at monitoring surface deformations generated by the pressurization of deep sub-horizontal fractures of a few meters extent. By imposing an oscillatory hydraulic load at the fractures' inlets, we are able to recognize the signature of their mechanical opening in tilt measurements. The recovered amplitudes lie around 10 nanoradians for a few centimeters of hydraulic head variations. From this we estimate fracture stiffnesses that are consistent in light of published data. Finally, we address the question of seasonal fluxes within a fractured aquifer and its link with recharge.Tilt signals are well correlated with annual head fluctuations at the study site. However, the remarkable difference is that tilt displays a phase lead of about one month with respect to piezometric levels. We interpret tilt time series with a 1D hydromechanical model and highlight the fact that the method is of interest for determining the large scale reservoir's geometry and that it is sensitive to recharge processes (local versus spread recharge, both in space and time). This novel result opens new perspectives as regards the estimation of recharge fluxes which is a major concern for water resources management. Hence, we conclude that surface tilt monitoring is a method with a strong potential to describe the properties and hydromechanical behavior of fractured media, from a few meters' scale up to several kilometers.

Magister Chirurgiae Dentium - MChD / Mandibular fractures are common facial injuries, occurring twice as frequently as fractures of the bones of the midface. Only the nasal bones are fractured more often as the result of trauma to the face (Olson eta/ 1982; Theriorletal 1987; Shepherd et al 1988; Dodson et al 1990; Lownie et al 1996). In many oral and maxillofacial units, the treatment of fractures of the mandible form the major proportion of the services rendered. Internationally it is accepted that there are two methods of treatment for fractures of the mandible, namely, closed and open reduction. Closed reductions are performed in dentate patients either under local or general anaesthesia. This method entails the placement of eyelet wires between or around teeth in both arches and then placing the patient into intermaxillary fixation. This is the method of choice when treating an undisplaced fracture of the mandible.