Este trabalho teve como objetivo realizar a investigação clínica dos efeitos do ultra-som de baixa intensidade como tratamento adjuvante na consolidação óssea de fraturas de ossos longos (rádio e ulna, fêmur, tíbia e fíbula) em cães. Foram utilizados 29 cães de raças variadas, 17 fêmeas e 12 machos, com faixa etária entre seis e 72 meses, 2,3 a 43 kg de peso corporal, portadores de fraturas recentes em ossos longos (rádio e ulna, fêmur, tíbia e fíbula), submetidos a procedimentos de osteossíntese (pinos intramedulares, fixação esquelética externa ou a associação destes métodos) e provenientes da rotina hospitalar de três instituições. Um dos cães apresentou fratura bilateral de tíbia e fíbula, tendo sido consideradas 30 fraturas. Os animais foram divididos em três grupos, de acordo com o local da fratura: GI (rádio e ulna), GII (fêmur), e GIII (tíbia e fíbula). Realizou-se o tratamento adjuvante de fraturas com ultra-som pulsado de baixa intensidade (30 mW/cm2 , durante 20 minutos, por 21 dias consecutivos) em 12 cães e 17 animais foram utilizados como controle. Todos os pacientes foram avaliados por exames clínicos e radiográficos nos períodos pré-operatório, pós-operatório imediato e aos 30 e 60 dias posteriores ao procedimento cirúrgico. Nos exames radiográficos foram observadas características de consolidação óssea, incluindo a presença ou ausência de reação periostal, ponte cortical, linha de fratura e formação de calo ósseo. O teste estatístico não paramétrico bilateral de Mann-Whitney foi empregado para a análise dos resultados dos achados radiográficos constatados nos animais dos grupos controle e tratado, não tendo sido verificadas diferenças significativas entre eles. Apesar da ausência de comprovação estatística, a maioria das fraturas tratadas com estimulação ultra-sônica demonstrou sinais clínicos e radiográficos de evolução favorável ao processo de consolidação óssea. Conforme os resultados observados neste estudo, o ultra-som pulsado de baixa intensidade pode ser indicado como tratamento adjuvante de fraturas recentes de ossos longos (rádio e ulna, fêmur, tíbia e fíbula), em animais da espécie canina. / This research had the purpose of investigating the clinical effects of low-intensity ultrasound on the healing of long bone fractures (radius and ulna, femur, tibia and fibula) in dogs. Twenty-nine dogs of different breeds were included in this study, being 17 females and 12 males, with ages ranging from six to 72 months, and weight from 2.3 to 43 kg. These animals presented a clinical history of recent long bone fractures (radius and ulna, femur, tibia and fibula), and underwent osteosynthesis procedures (intramedullary pins, external skeletal fixation or the association of both). All of the animals originated from three different veterinary hospitals. One of the dogs presented bilateral tibial fracture, encompassing a total of 30 fractures in such group. The animals were divided into three groups, according to the fracture site: GI; (radius and ulna), GII (femur), and GIII (tibia and fibula). The treatment with pulsed low-intensity ultrasound (30 mW/cm2 , for 20 minutes, for 21 consecutive days) was performed on 12 dogs, using 17 animals as a control group. All patients were evaluated through physical and radiographic examination before surgery, immediately on the postoperative, and after 30 and 60 days from the osteosynthesis. Postoperative and follow-up radiographs were examined for periosteal reaction, cortical bridging, fracture line and callus. The non-parametric bilateral Mann-Whitney Test was used to investigate the radiographic findings in the group undergoing treatment and in the control group. There were no significant statistical differences between them. In spite of these statistical results, most of the fractures treated with pulsed low-intensity ultrasound showed clinical and radiographic signs of bone healing in progress. According to these results, pulsed low-intensity ultrasound can be indicated as an adjunctive treatment for recent long bone fractures (radius and ulna, femur, tibia and fibula) in dogs.

Made available in DSpace on 2014-06-11T19:31:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-05-06Bitstream added on 2014-06-13T19:20:06Z : No. of bitstreams: 1 ribeirojunior_pd_dr_araca.pdf: 475855 bytes, checksum: 25027ddf9644c9757d0a760d4ed4ca58 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este estudo avaliou in vitro a influência do tipo de miniplaca (convencional ou locking) e do número de parafusos instalados no segmento ósseo distal e proximal para a promoção da estabilidade óssea e resistência da osteossínteses pelo método Champy, utilizada para o tratamento de fraturas de ângulo mandibular. Sessenta hemi-mandíbulas de poliuretano, com consistência similar ao osso mandibular, foram divididas em 4 grupos (n=15) e seccionadas na região de ângulo mandibular simulando uma fratura. Os segmentos ósseos foram fixados por diferentes tipos de miniplacas usando sistema 2.0- mm e parafusos monocorticais de 2.0 x 6.0mm. Nos grupos 1 e 2, dois parafusos convencionais (G1) ou locking (G2) foram instalados em cada segmento ósseo usando respectivamente miniplacas retas convencionais e locking; Nos grupos 3 e 4, três parafusos convencionais (G3) ou locking (G4) foram instados no segmento ósseo proximal e quatro parafusos convencionais (G3) ou locking (G4) foram instalados no segmento distal, usando uma miniplaca convencional (G3) e locking (G4) de sete furos, reta. As hemi-mandíbulas foram submetidas a um teste de compressão utilizando uma máquina universal de ensaio INSTRON até que houvesse um distanciamento entre os segmentos ósseos de 4 mm, seja no sentido horizontal ou vertical. Os dados registrados foram submetidos à avaliação estatística pelo método ANOVA e teste de Tukey utilizando um nível de significância de 1%. As miniplacas locking ofereceram maior resistência ao teste de compressão do que as miniplacas convencionais (p<0.01). Porém, não existiu diferença entre o uso de miniplacas de 7 ou 4 furos (p>0.01). Apesar de não estatisticamente significante os resultados numéricos sugeriram que as miniplacas locking longas oferecem maior resistência ao teste de compressão que as miniplacas locking curtas. / This study evaluated in vitro the influence of the type of miniplate (conventional or locking) and the number of screws installed in the proximal and distal segments on the stability and resistance of Champy’s osteosynthesis in mandibular angle fractures. Sixty polyurethane hemimandibles with bone-like consistency were randomly assigned to 4 groups (n=15) and sectioned in the mandibular angle region to simulate fracture. The bone segments were fixed by different osteosynthesis methods using 2.0-mm miniplates and 2.0 x 6 mm monocortical screws: Groups 1 and 2- Two conventional (G1) or locking (G2) screws were installed in each bone segment using either a conventional (G1) or a locking (G2) straight miniplate; Groups 3 and 4- Three conventional (G3) or locking (G4) screws were installed in the proximal segment and four conventional (G3) or locking (G4) screws were installed in the distal segment using a either a conventional (G3) or a locking (G4) 7-hole straight miniplate. The hemimandibles were loaded in compressive strength in an Instron machine until a 4-mm displacement occurred between the segments either vertically or horizontally. Data were analyzed statistically by ANOVA and Tukey’s test at 1% significance level. The locking plate/screw systems provided significantly greater resistance to displacement under compressive load than the conventional plate/screw systems (p<0.01). However, no statistically significant difference was found between 7-hole and 4-hole miniplates (p>0.01). In conclusion, the locking miniplates offered more resistance than conventional miniplates and long locking miniplates provided greater (number results) bone stability compared to short ones.

As fraturas do ângulo mandibular são muito frequentes dentre as fraturas mandibulares e um das formas de tratamento é a utilização de fixação interna com placas e parafusos. Neste estudo o objetivo foi avaliar comparativamente a resistência de três tipos de fixação em réplicas de mandíbula de poliuretano. Foram utilizadas 63 mandíbulas dentadas, submetidas a seccionamento simulando uma fratura linear e desfavorável de ângulo mandibular esquerdo. As fixações foram realizadas com placas do sistema 2,0 mm, dispostas da seguinte forma: uma placa reta de quatro furos, uma placa reta de quatro furos com extensão (ponte) e uma placa 3D 4 furos. Cada grupo (n = 21) foi submetido ao teste de resistência linear com aplicação de carga no sentido súpero-inferior em três pontos distintos da mandíbula, de modo não simultâneo (região do primeiro molar ipsilateral à secção, primeiro molar contralateral e incisivos centrais) em máquina de ensaio universal EMIC DL 2000. Foram mensurados valores de carga no deslocamento de 1 mm, 2 mm e 5mm. Os resultados obtidos foram submetidos à análise estatística, utilizando a análise de variância (ANOVA), nível de significância de 5%. Os valores obtidos, não apresentaram diferença estatisticamente significante entre as placas. Os resultados mostraram que as placas 3D produzem escores similares às placas usadas convencionalmente. Com base nos resultados obtidos, pode-se concluir que os três tipos de fixação se comportam de forma similar. / Mandibular angle fractures are very frequent among the mandibular fractures and a form of treatment is the use of internal fixation with plates and screws. In this study, the objective was to evaluate the resistance of three types of fixation in mandibular replicas of polyurethane. Sixty three toothed mandibles were used, subject to sectioning simulating a linear and unfavorable fracture of left mandibular angle. The fixations were performed with straight plates system 2.0 mm, prepared as follows: one plate with 4-holes, one 4-holes and extension (bridge) and one plate 3D 4-holes .Each set was submitted for loading test with load application towards in three distinct points of the mandible, so do not simultaneously (molar region on the side ipsilateral of section, the central incisors and contralateral molar) in universal testing machine EMIC DL 2000. Load values were measured at offset 1 mm, 2 mm and 5mm and was noted the final dislocation. The results were submitted to statistical analysis, using analysis of variance (ANOVA), a significance level of 5%. the values obtained showed no statistically significant difference between the plates. The results show that the 3D plate can reproduce similar mechanical scores to the plates used conventionally. It can be concluded that the three types of fasteners behaved similarly.

Uma das grandes preocupações com o envelhecimento populacional é o aumento na prevalência de doenças crônicas e degenerativas como as psiquiátricas, cardiovasculares, metabólicas e fraturas de fêmur, bem como o aumento no consumo de medicamentos. A fratura de fêmur é um episódio que compromete muito a funcionalidade e a qualidade de vida dos idosos. Ela é causada principalmente por quedas, principalmente em idosos portadores de osteoporose. A queda se dá em parte pela decorrência da perda do equilíbrio postural. As principais causas para a ocorrência de quedas na população idosa são ambiente inadequado, doenças neurológicas e doenças cardiovasculares. O presente estudo objetivou identificar os principais fatores que contribuíram para as quedas com fraturas e quedas sem fraturas de fêmur em idosos no município de São Sebastião do Paraíso. Foi realizado um estudo caso-controle, onde foram selecionados 45 pacientes de ambos os sexos com 60 anos ou mais de idade que sofreram fraturas de fêmur decorrentes de queda (casos) e dois grupos controles (45 indivíduos em cada grupo), na proporção de 1:1:1, onde um grupo foi composto por idosos de ambos os sexos que sofreram quedas mas não fraturas de fêmur e o outro grupo composto por idosos que não sofreram queda nem fratura no município de São Sebastião do Paraíso/MG. Os dados foram coletados a partir de entrevistas realizadas nos domicílios dos participantes, bem como levantamento de informações em prontuários. Para a análise estatística de diferenças entre proporções, médias e medianas foram utilizados, respectivamente o teste quiquadrado, o t de Student e de Kruskal-Wallis. Para a análise de associação entre variáveis foram realizadas inicialmente análises univariadas e posteriormente análises multivariadas empregando-se regressão logística. Como medida de efeito foi empregado o Odds Ratio (OR) e seu Intervalo de Confiança a 95% (IC95%). Em todas as análises considerou-se um nível de significância de 5%. Os resultados do estudo mostraram que os idosos que não fraturaram o fêmur e que não sofreram queda foram menos suscetíveis à morte do que os que fraturaram; a maioria das quedas e das fraturas de fêmur ocorreu na rua e no quintal de casa e que pessoas idosas do sexo feminino foram mais suscetíveis a sofrê-las; entre os idosos que praticam atividade física, apenas 1 sofreu fratura de fêmur; a maioria dos idosos que fazem uso de medicamentos é do sexo feminino. Os fatores associados à proteção contra fratura de fêmur foram: receber algum tipo de remuneração, ouvir bem e possuir corrimão nas escadas de suas residências. Os fatores associados ao risco para fratura de fêmur foram: hipertensão arterial sistêmica, sedentarismo, uso de anti-hipertensivos e possuir superfície escorregadia na residência. Os fatores de proteção para queda Resumo foram: possuir corrimão nas escadas de suas residências, uso de antidepressivo, ser portador de osteoporose e depressão. Os fatores associados ao risco de queda foram: sedentarismo e possuir tapetes nas residências. O estudo concluiu que as principais medidas a serem adotadas para prevenir as quedas e as fraturas de fêmur são: praticar atividades físicas, reduzir o uso de medicamentos psicotrópicos e realizar alterações no ambiente residencial. / One of the biggest worries with the population aging is the rising of the chronic and degenerative as psychiatric, cardiovascular, metabolic diseases and femur fractures, also the rising of medication consumption. The femur fracture is an episode that compromises a lot the workability and the quality of life of the elderly people. It is mainly caused by falls, especially for those who have osteoporosis. The fall is partially due to the total loss of postural balance. The mainly facts linked to the fall occurrences on elderly population are inappropriate ambient, neurological diseases and cardiovascular diseases. This study aimed to identify the main factors that contributed to the falls at femur fractures and falls without femur fractures on elderly people in the city of São Sebastião do Paraíso. It was performed a case-control study where were selected as the cases 45 patients of both genders with 60 years old, or more who have suffered femur fractures derived from fall and two groups as controls (45 individuals in each group), in the proportion of 1:1:1, where a group was consisted from elderly of both gender who suffered falls but not femur fractures and other group consisted of elderly people who didnt suffer any falls in the city of São Sebastião do Paraíso/MG. The data were collected from interviews realized on the participants houses, as well as the gathering of information on the records. For the statistical analysis of differences between the proportions, means and medians were used, respectively the chi-squared, Student t and Kruskal-Wallis tests. To the association analysis between the variables were initially performed univariate analysis and then multivariate analysis using logistic regression. As measure effect was used the Odds Ratio (OR) and its Confidence Interval at 95% (95%CI). In all the analysis was considered a significance level of 5%. The study results showed that the elderly people that did not fracture the femur and did not suffer any fall were less susceptible to death than those who did it; the major number of falls and femur fractures happened on the streets and at the backyards and the elderly female people were more susceptible to suffer it; among elderly people who practice physical activity, only one suffered femur fracture; the great number of the elderly people who use medicine is from the female gender. The protective factors to femur fracture were: earn some kind of remuneration, listen well and have houses with a handrail on the stairs. The risk factors to femur fracture were: systemic arterial hypertension, sedentary life, use of anti-hypertensive and own a slippery surface at their residences. The protective factors to the falls were: to have a handrail stair on their residences, use of antidepressant, to have Abstract osteoporosis and depression. The fall risk factors were: sedentary life and own tapestry on the residences. The study concluded that the mainly activities to be adopted to prevent the falls and femur fractures are: to practice physical activity, to reduce the usage of psychotropic medicine, and to make residential adjustments.

Tem havido grande interesse na investigação de substâncias de ação sistêmica que atuam sobre o sistema musculoesquelético, no sentido de melhorar a qualidade óssea e muscular, e assim, evitar fraturas patológicas decorrentes de osteoporose. Os esteroides anabólicos androgênicos têm importante atuação no metabolismo sistêmico geral, sendo que no osso aumenta sua resistência, massa e, no músculo, combate a sarcopenia. Entretanto, não há investigações consistentes sobre a possível atuação dessas substâncias na consolidação óssea. Este estudo teve como objetivo avaliar o efeito do decanoato de nandrolona na consolidação óssea e na qualidade óssea de fêmures de ratos machos adultos jovens da linhagem Wistar. Foram utilizados 112 animais, divididos em 04 grupos com 02 subgrupos (14 e 28 dias). Um grupo controle (n=17) foi formado por animais sem intervenção, mas apenas com a injeção de veículo inerte. Em outro grupo foi provocada fratura da diáfise do fêmur (n=26). No terceiro grupo os animais receberam apenas decanoato de nandronola (n=23). No quarto grupo foi provocada fratura na diáfise do fêmur associada à administração da mesma dosagem de decanoato de nandrolona (n=26). A fratura provocada no fêmur foi pelo método fechado e obtida com auxílio de uma guilhotina com lâmina romba. Em seguida, a fratura foi fixada por um fio de Kirschner de 1,0 mm de espessura, inserido no canal medular, e o membro pélvico foi radiografado em perfil. O decanoato de nandrolona foi aplicado na dose de 10 mg/kg de massa corporal, por via intramuscular, 02 vezes por semana, durante 14 ou 28 dias, conforme o subgrupo. Após a eutanásia os fêmures direitos foram dissecados e tiveram o comprimento medido. A densidade mineral óssea e o conteúdo mineral ósseo foram determinados pelo método da absorciometria de raios X de dupla energia (DXA). A resistência óssea foi determinada pelo ensaio mecânico de flexão em dois pontos, com o cálculo com a da força máxima e rigidez. O calo ósseo foi avaliado microscopicamente em cortes histológicos corados pela hematoxilina e eosina e examinados em luz comum para a obtenção do seu volume por técnica morfométrica. As outras secções foram coradas em picrosirius red e examinadas em luz polarizada para a quantificação do colágeno tipo I. A significância estatística foi estabelecida em 5%. Não houve diferença significante entre os animais tratados e não tratados pelo decanoato de nandrolona quanto à densidade mineral óssea, conteúdo mineral ósseo, resistência mecânica, tanto para o osso sem fratura, quanto para o calo ósseo. A quantidade de colágeno tipo I também não foi diferente, entretanto, o volume de osso neoformado nos grupos que receberam o esteroide anabolizante foi significantemente maior. A massa corporal foi maior nos grupos que receberam decanoato de nandrolona, embora sem significância estatística. O comprimento ósseo foi maior aos 28 dias no grupo tratado com decanoato de nandrolona. A massa do calo também teve valor significativamente maior aos 28 dias nos animais que receberam o decanoato de nandrolona. Com base nos resultados encontrados, sob as condições experimentais e métodos de avaliação empregados, o decanoato de nandrolona não causou efeitos significativos benéficos ou maléficos, tanto na qualidade do calo ósseo, como na qualidade do osso normal íntegro do rato adulto jovem. / There has been a great interest in investigating systemic substances that can positively act on the musculoskeletal system to improve the bone quality thus avoiding osteoporotic fractures. The anabolic androgenic steroids have an important influence on general metabolism and can increase the bone resistance and bone mass. On muscle, it improves sarcopenic conditions. However, there is no consistent investigation of a possible action of these substances on bone callus. Thus, the aim of this study was to evaluate the effect of decanoate of nandrolone on fracture healing and bone quality of young adult male Wistar rats. One hundred animals were divided into 04 groups and 02 subgroups (14 and 28 days). A control group consisted of animals without any intervention (n=17). In the second group, a femoral shaft fracture was performed (n=26). In the third group, the animals received only decanoate of nandronole (n=23). In the fourth group, a fracture in the femoral shaft was performed and associated with administration of the same dose of decanoate of nandrolone (n=26). The fracture created in the femur was obtained by closed method and achieved with the aid of a blunt blade guillotine. After that, the fracture was fixed with a 1.0 mm thick Kirschner wire that was inserted into the medullary canal, and the limb was X-rayed in profile. Ten mg/kg of body mass of decanoate of nandrolone was administered intramuscularly, 02 times a week for 14 or 28 days, depending on the subgroup. After euthanasia, the right femurs were dissected and had the length measured. Bone mineral density and bone mineral content were determined by the dual-energy x-ray absorptiometry method (DXA). The mechanical properties maximum force and stiffness were determined by the twopoint bending test. The bone callus was evaluated microscopically in sections stained with hematoxylin and eosin and examined under ordinary light microscope to calculate the volume of bone callus by the morphometric technique. Other sections were stained in picrosirius red and examined under polarized light for quantification of type I collagen. The statistical significance was set at 5%. There was no significant difference between the animals treated and not treated with nandrolone decanoate for bone mass density, bone mineral content, mechanical resistance and type I collagen, both for the intact bone and for the bone callus. However, the body mass was higher in the groups that received nandrolone decanoate, although without statistical significance. The femur length was greater in the 28th day in the group treated with nandrolone decanoate. Callus mass also had significant increase at 28 days for animals that received nandrolone decanoate. Based on the results and under the experimental conditions and methods of evaluation, the decanoate of nandrolone did not cause significant benefit or harmfull effects both on callus and on bone qualities.

Introduction The consequences of falling can be fatal to elderly. The mortality, morbidity and the risk ofanxiety and depression increases following a fall. Drug prescription is a preventable fall risk,making the association between antihypertensive medications and risk of falling an importantarea of investigation. Aim Compile the results from studies which have examined the effect of initiating or changing theantihypertensive medication on fall risk in people aged 60 years or older. Methods Data sources: MEDLINE and Cochrane databases. Study selection: Original articles ofcohort-, case control-, case crossover-, cross-sectional- and randomized controlled trial type,published between January 2000 and May 2019 and written in English were included. Dataassessment: 6 studies met the criteria and were included. Study quality was assessed for eachstudy. Results Three studies found significant short-term increase in fall risk, regardless of drug type. Onestudy discovered an 18% increase in fall risk for every 5-day gap in treatment. Two studiesevaluated antihypertensive drug types separately and found contradictive results of thiazidediuretics on short-term fall risk. Calcium channel blockers showed a protective effect andbeta blockers an increased risk during the first 3 weeks after initiating treatment. Conclusions No consistent consensus was seen regarding the short-term fall risk in separateantihypertensive drug types, though most studies agree in a short-term risk increase aftergeneral antihypertensive treatment initiation or change.

Geothermal energy is being explored as a supplement to traditional fossil fuel resources to meet growing energy demand and reduce carbon emissions. Geothermal energy plants harvest heat stored in the Earth’s subsurface by bringing high temperature fluids to the surface and generating steam to produce electricity. Development of geothermal resources is often inhibited by large upfront risk and expense. Successful mitigation of those costs and risks begins with efficient characterization of the resource before development. A typically successful geothermal reservoir consists of a fractured reservoir that conducts hydrothermal fluids and a cap rock seal to limit convective heat loss through fluid leakage. The controls on the system include the density and orientation of fractures, mechanical rock properties, and the local stress field acting on those rocks. The research presented in this dissertation utilizes diverse data sets to characterize core, wireline borehole logs, and laboratory data to describe the distribution of fractures, rock properties, and the orientation and magnitude of stresses acting on the borehole. The research demonstrates there is a potential resource in the region and describes the controls on the vertical extent of the hydrothermal fluids. The distribution of fractures is controlled by the distribution of elastic rock properties and rock strength. A cap rock seal is present that limits hydrothermal fluid loss from a fractured artesian reservoir at 1,745 m (5,726 ft). In addition to characterization of the resource, this research demonstrates that an equivalent characterization can be used in future exploration wells without the expense and risk of collecting core. It also demonstrates that multiple methods of analysis can be utilized simultaneously when some data are not available. Data collection from deep wellbores involves risk and data loss or tool failure is a possibility. In these cases, our methods show that successful characterization is still possible, saving time and money, and minimizing the financial risk of exploration

Naturally fractured reservoirs have attracted an increased interest of exploration and production geophysics in recent years. In many instances, natural fractures control the permeability of the reservoir, and hence the ability to find and characterize fractured areas of the reservoir represents a major challenge for seismic investigations. In fractured and porous reservoirs the fluid affects elastic anisotropy of the rock and also causes significant frequency dependent attenuation and dispersion. In this study we develop a mathematical model for seismic wave attenuation and dispersion in a porous medium in a porous medium with aligned fractured, caused by wave induced fluid flow between pores and fractures. In this work fractures in the porous rock are modelled as very thin and highly porous layers in a porous background. Dry highly porous materials have low elastic moduli; thus dry skeleton of our system contains thin and soft layers, and is described by linear slip theory. The fluid saturated rock with high-porasity layers is described by equations of poroelasticity with periodically varying coefficients. These equations are analyzed using propagator matrix approach commonly used to study effective properties of layered system. This yields a dispersion equation for a periodically layered saturated porous medium taking into account fluid communication between pore spaces of the layers. Taking in this dispersion equation a limit of small thickness for high-porosity layers gives the velocity and attenuation as a function of frequency and fracture parameters. The results of this analysis show that porous saturated rock with aligned fractures exhibits significant attenuation and velocity dispersion due to wave induced fluid flow between pores and fractures. / At low frequencies the material properties are equal to those obtained by anisotropic Gassmann theory applied to a porous material with linear-slip, interfaces. At high frequencies the results are equivalent to those for fractures with vanishingly small normal slip in a solid (non-porous) background. The characteristic frequency of the attenuation and dispersion depends on the background permeability, fluid viscosity, as well as fracture density and spacing. The wave induced fluid flow between pores and fractures considered in this work has exactly the same physical nature as so-called squirt flow, which is widely believed to by a major cause of seismic attenuation. Hence, the present model can be viewed as a new model of squirt-flow attenuation, consistent with Biot’s theory of poroelasticity. The theoretical results of this work are also limited by the assumption of periodic distribution of fractures. In reality fractures may be distributed in a random fashion. Sensitivity of our results to the violation of the periodicity assumption was examined numerically using reflectivity modelling for layered poroelastic media. Numerical experiments for a random distribution of fractures of the same thickness still show surprisingly good agreement with theoretical results obtained for periodic fractures. However this agreement may break down if fracture properties are allowed to vary from fracture to fracture. The results of this thesis show how to compute frequency dependences of attenuation and velocity caused by wave induced fluid flow between pores and fractures. These results can be used to obtain important parameters of fractured reservoirs, such as permeability and fracture weakness, from attenuation measurements. The major requirement for the success of such an approach is that measurements must be made in over a relatively broad frequency range.

Naturally fractured reservoirs are generally extremely complex. The aim of characterisation and modelling of such reservoirs is to construct numerical models of rock and fractures, preparing input data for reliable stimulation and fluid flow simulation analyses. This requires the knowledge of different fracture heterogeneities and their correlations at well locations and inter-well regions. This study addresses the issues of how to integrate different information from various field data sources and construct comprehensive discrete fracture networks for naturally fractured reservoir. The methodology combines several mathematical and artificial intelligent techniques, which include statistics, geostatistics, fuzzy neural network, stochastic simulation and simulated annealing global optimisation. The study has contributed to knowledge in characterisation and modelling of naturally fractured reservoirs in several ways. It has developed: .An effective and data-dependant fracture characterisation procedure. It examines all the conventional reservoir data sources and their roles towards characterisation of different fracture properties. The procedure has the advantage of being both comprehensive and flexible. It is able to integrate all multi-scaled and diverse fracture information from the different data sources. .An improved hybrid stochastic generation algorithm for modelling discrete fracture networks. The stochastic simulation is able to utilise both discrete and continuum fracture information. It could simulate not only complicated distributions for fracture properties (e.g. multimodal circular statistics and non-parametric distributions) but also their correlations. In addition, with the incorporation of artificial fuzzy neural simulation, discrete multifractal geometry of fracture size and fracture density distribution map could be evaluated and modelled. Compared to most of the previous fracture modelling approach, this model is more flexible and comprehensive. .An improved conditional global optimisation model for modelling discrete fracture networks. The hybrid model takes full advantages of the advanced fracture characterisation using geostatistical and fuzzy neural analyses. Discrete fractures are treated individually and yet continuum information could be modelled. Compared to the stochastic simulation approach, this model produces more representative fracture networks. Compared to the conventional optimisation programs, this model is more versatile and contains superior objective function.

The management of significant bone defects, delayed and non-union of fractures can be extremely challenging. Development of specific treatment is hindered by an absence of information regarding the molecular events which regulate these processes. In this thesis, a bilateral cancellous bone defect model of the femur and tibia was developed in a rodent and the spatiotemporal profile of TGF-β, BMP 2 and 7, Smads 1, 4 and 5 characterised. Next, the capability of acid solution to augment healing was tested in both a bone defect and in a closed femoral fracture model. Finally, a long term oestrogen deficiency (OVX) rat model of postmenopausal osteoporosis was characterised and the spatiotemporal profiles of IGF-1, IGFR-1, MMP-1, MMP-3, MMP-9, MMP-13, TIMP-1, TIMP-2, BMP-2, BMP-4, BMP-7, TGF-β, Smad4, Smad7, VEGF, Flt-1, Ihh and FGF-2 were compared in femoral osteotomies between OVX and Sham groups. The bilateral cancellous defect model was successfully created with a number of advantages with which to recommend its use in future studies. TGF-β, BMP 2 and 7, Smads 1, 4 and 5 had characteristic spatiotemporal profiles during cancellous bone defect healing suggesting that they have a regulatory role. The results of the acid study were inconclusive and problems with substance delivery and maintenance at the desired site need to be addressed in the future to fully test this hypothesis. No significant differences were detected on histology or three-point mechanical testing between the fracture calluses of acid and control groups. In the final study, OVX rats after six months had significantly increased weight and decreased bone mineral density compared to their sham counterparts. A histological delay in osteotomy healing was observed in the OVX group but no significant differences on tensile testing were seen between OVX and Sham groups up to six weeks. Immunohistochemistry revealed that delayed healing may be due to the down-regulation of IGF-1, BMP-2, 4, and 7 and the up-regulation of MMP-3 in OVX compared to Sham groups. In conclusion, the results of this thesis give some insight into the molecular biology of bone defects and osteoporotic fractures. This information may also be useful in the development of specific treatments aimed at augmenting healing in bone defects and osteoporotic fractures.