Thesis (Ph.D.)--York University, 2003. Graduate Programme in Women's Studies. / Typescript. Includes bibliographical references (leaves 196-202). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99173

AIMS: Multiple studies have shown that arthrocentesis is an effective treatment for internal derangement of the temporomandibular joint. However, it is not known which patient groups will respond to this procedure. It is often difficult for surgeons to preoperatively the outcome of athrocentesis. This had led some researchers to analyze and evaluate specific variables which could possibly be used as prognostic factors to predict the outcome of arthrocentesis. None of those studies used the amount of disc displacement as a prognostic factor to assess the treatment outcome of arthrocentesis. Therefore, our study objective was to evaluate the amount of disc displacement as a prognostic factor for the outcome of arthrocentesis in patients with Internal derangement of the tempromandibular joint. MATERIALS AND METHODS: The study involved a retrospective review of the treatment records of 46 patients who underwent arthrocentesis of the TMJ by a single surgeon between 2010 and 2013. A prognostic factor evaluated for its effect on the treatment outcome of TMJ arthrocentesis in this study was the degree of disc displacement. For study purposes, patients were divided into two groups: 1) Success group, and, 2) Failure group. Patients were categorized as successful if they met the success criteria prescribed by the American Association of Oral and Maxillofacial Surgeons in 1995. MRI of TMJ was performed in two steps. Initially, oblique parasagittal sections were scanned with a 1.5 T MRI machine. The amount of disc displacement was analyzed from sagittal oblique views of the MRI scans in closed mouth positions by measuring the angle between the posterior band of the articular disc and the center of the condylar head. The disc is considered to be in its normal position when the thicker portion of its posterior band lies within ±10° on the 12 o'clock position. First, the condylar head was identified, and a circle was established to describe the outline of the anterior, posterior, and superior surfaces of the condylar head; this allowed separation of the condylar head from the neck region. Second, the center of the circle was identified and a vertical line was drawn from the center of the circle. The last step was to measure the degree of displacement from this vertical line to the posterior band of the disc. Findings were compared for patients in the two groups for the following variables: age (continuous), disc displacement (continuous), and gender (female or male). P-value were calculated for differences in continuous or categorical variables using a T-test or Pearson's chi-squared test, respectively. The mean MMO, pain and diet scores were also reported in the preoperative group and 12 months postoperative group by outcome status. Statistical significance was set at p < .05 based on a two-tailed test. SPSS was used for all statistical analyses (SPSS Inc, Chicago, IL, 1997). RESULTS: 46 patients with 46 joints were evaluated in the present study. Average age of patients was 31 years with arrange of 24 to 46 years. 35 cases (76.1%) were classified as successful and 11 cases (23.9%) were classified as unsuccessful based on the criteria described earlier. In the successful group, the mean MMO score was found to be greater at the 12 months postoperative interval when compared to the preoperative examination. In the unsuccessful group, the mean MMO score was also greater than preoperatively at the 12 months postoperative group but to a lesser extent than seen in the successful group. Pain level improved more in the successful group compared to the unsuccessful group. Diet scores showed improvement in chewing ability in the successful group but remain unchanged in the unsuccessful group There was a statistically significant difference between the two groups in the degree of anteriorly disc displacement. CONCLUSION: In summary, it has been shown that the degree of disc displacement, preoperative pain level, diet score, and MMO can be used as prognostic factors for the outcome of TMJ arthrocentesis. Future investigations should more carefully evaluate the validity of other variables. Identifying prognostic factors for the outcome on arthrocentesis will help with guiding surgeons in the planned evaluation of TMJ cases. More specifically, clinicians will be able to create tailored treatment modalities based upon prognostic factors.

Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-02

This study has examined 3D stresses and displacements around a longwall mining system that is intercepted by a geological fault. More specifically, the study has analyzed the effect of a fault on longwall gate development entries, set-up rooms, T-junctions, and the longwall face as the longwall face progressed toward, through, and away from the fault. A general lithologic sequence and mining parameters related to the Herrin No. 6 coal seam in southern Illinois were employed. FLAC3D structural analysis code was used for simulating two (2) adjacent longwall faces. Linear elastic rock mass elements with non-linear elastic-plastic fault elements were analyzed using Hoek- Brown brittle failure criteria. Two (2) models were developed for analysis: a base elastic case without fault and an elastic model with elastic-plastic fault elements. Engineering properties for the rock mass strata were derived from a history of rock core testing and modified following the process indicated for Hoek’s Geologic Strength Index. Gob engineering properties and estimated load carrying capacities developed in earlier studies were used to make simulations physically realistic. The local tectonic (horizontal) stress field and vertical stress levels were applied to the simulation boundaries. Analysis data was extracted for several data lines in the roof and floor that were determined to be critical based on the geometry of the mine layout. Extracted data included 3D stresses and displacements with the Z-direction indicating vertical. This data was used to calculate vertical convergence and vertical and horizontal stress concentration variables VSCF, HSCF-XX, and HSCF-YY. Such data were developed for the longwall face advancing in 30-foot (10-m) increments away from the set-up room. Incremental displacements due to the fault proved to be more significant than changes in stress concentrations VSCF, HSCF-XX, and HSCF-YY. Set-up room X-displacements show a consistent increase in the fault case around 35%. Incremental Y-displacements vary sharply at first then changes quickly reduce to zero (0). Z-displacements were similar in both models. A fault oriented more vertically would have larger Z-displacement values. Gate X-displacements significantly decrease in the fault model until the face reaches 558 feet (170 m) from the starting point. Y-displacements show a rapid percentage rise in the fault model as the longwall face approaches the intersection of the fault with the first gate entry, but significant percentage decreases both before and after reaching this intersection. Significant increases in Z-displacements occur as the face approaches and leaves the intersection of the fault with the gate entries. Around the fault, the first row of gate pillars experiences a change in horizontal displacements HSCF-XX and HSCF-YY of approximately 10%. Second row pillars also see a change in HSCF-XX of around 10%, but not a significant change in HSCF-YY. Gate entry VSCF values show significant increases at the fault intersection until the face passes the gate/fault intersection.

Este texto é uma reflexão sobre os pressupostos que fizeram parte do meu processo de trabalho em artes visuais nos últimos anos e que continuam em desenvolvimento. A investigação parte de um pressuposto gerado de três séries de trabalhos, Bambu, bambuí, Sobreposições e Imersão Rio, que se conectam por um deslocamento entre três ambientes: paisagem, ateliê e galeria. Ao rastrear as influências recorrentes em minha produção, acesso um momento histórico específico por onde permeio minha pesquisa e procuro compreender os procedimentos, ações e estratégias que compõem minha poética artística / This text is a reflection on the presuppositions which were part of my process of work on visual arts in the recent years and continue to develop. The research starts on a presupposition generated by three series of works, Bambu, bambuí, Sobreposições and Imersão Rio, which are connected by a displacement from three environments: landscape, studio and gallery. By tracking the recurrent influences in my production, I access the specific historical moment where I permeate my research and I try to understand the procedures, actions and strategies that compose my artistic poetics

The study of the buoyancy–driven displacement ventilation flows has been conducted earlier through both mathematical modelling and experiments. There can be some assumptions made in the studies for thermal analysis such as: adiabatic boundaries, neglecting radiation heat transfer between wall surfaces, and neglecting the absorptivity of the air on simulating the thermal distribution within the ventilated spaces. This study considers heat conduction at boundaries, heat radiation between wall surfaces and radiative absorptivity of the air when modelling buoyancy-driven displacement ventilation flows. The simulations were carrying out using computational fluid dynamic (CFD) programme Star-CCM+. This study investigates the influence of the absorptivity of the air on thermal distribution within an enclosure ventilated by buoyancy-driven displacement ventilation flows. Two cases of buoyancy-driven displacement ventilation experiments conducted early by Sandbach (2009) and Li et al. (1993b) were modelled. To consider the absorptivity of the air, the local weather data were retrieved and were used for calculating the absorption coefficient of the air under different weather conditions. The participating media radiation model was employed to compute the radiation heat absorbed by the air. In addition, the performances of the turbulence models on modelling buoyancy-driven displacement ventilation flows were investigated to ensure the predicted results were accurate and satisfactory. The simulation results presented in this study have shown to agree well with the experimental data in two different experiment cases. In the case of the experiments conducted by Sandbach and Lane-Serff (2011b), the predicted results match well with the measurements when considering absorptivity of the air. The errors between the simulation results and the measurements were less than 10% in most cases. The results also suggest that the absorption coefficient has an influence on ventilation flow rate and consequently has an effect on the strength of the stratification. This indicates that the absorption coefficient should be determined according to the conditions rather than be given an one-and-for-all value. The simulation results have also shown to agree well with the measurements given in the literature presented by Li et al. (1993b). The effect of the absorptivity was shown to be more significant in the case of high supply airflow temperature or high supply heat load. Hence, radiative absorptivity of the air should be taken into account in order to accurately model the thermal distribution in the ventilated enclosure.

This study investigates livelihood patterns and gender arrangements during displacement. The main focus is on the experience of internally displaced persons at Al-Salam and Mayo displaced persons' camps at the outskirts of Khartoum, the capital of Sudan. The study uses an integrated gender conceptual framework, which encompasses Moser's triple role framework, practical and strategic gender interests and Kabeer's social relations framework, as well as agency and empowerment concepts and finds that, at places of origin, people were mainly dependent on farming and rearing of animals to earn a living. However, differences existed between regions. This way of livelihood was associated with 'traditional' gender arrangements, where men were the main breadwinners with no clear reproductive roles. By contrast, women's main roles were primarily reproductive. Then war, drought and famine affected people's livelihoods and led to displacement. At the displacement camps, more women than men were able to develop illegal and legal livelihood strategies. These new livelihood patterns upset the old gender patterns and led to emergence of new gender arrangements. Moreover, displaced women were able to build relationships within their gender and to form tajammu'at (women's groups). The NGOs (Non Governmental Organisations) which were active in the displacement camps tended to perceive the displaced as powerless victims, but in practice, displaced women had become social agents and were able to demonstrate empowerment, resilience, and ability to cope with displacement conditions

Este texto é uma reflexão sobre os pressupostos que fizeram parte do meu processo de trabalho em artes visuais nos últimos anos e que continuam em desenvolvimento. A investigação parte de um pressuposto gerado de três séries de trabalhos, Bambu, bambuí, Sobreposições e Imersão Rio, que se conectam por um deslocamento entre três ambientes: paisagem, ateliê e galeria. Ao rastrear as influências recorrentes em minha produção, acesso um momento histórico específico por onde permeio minha pesquisa e procuro compreender os procedimentos, ações e estratégias que compõem minha poética artística / This text is a reflection on the presuppositions which were part of my process of work on visual arts in the recent years and continue to develop. The research starts on a presupposition generated by three series of works, Bambu, bambuí, Sobreposições and Imersão Rio, which are connected by a displacement from three environments: landscape, studio and gallery. By tracking the recurrent influences in my production, I access the specific historical moment where I permeate my research and I try to understand the procedures, actions and strategies that compose my artistic poetics

Whole body vibration (WBV) delivers a stimulus to the body via an oscillating platform and remains a relatively new area of research. Several applications of WBV stimuli have been developed as strength training and rehabilitation modalities, but inconsistent results have been published. There is little knowledge underpinning the mechanisms to explain the elicited neuromuscular responses to WBV and a wide range of WBV parameters across the literature. As a result, safe and effective protocols are yet to be established or validated. The aim of this current research was to investigate: the electromyography (EMG) and explosive performance responses to varying WBV frequencies; the effect of WBV data analysis techniques; and the influence of external factors on WBV stimulus and neuromuscular responses. Three main studies were completed: 1. An individualised response of both EMG and jump performance appears to exist dependent on vertical WBV frequency, in trained participants. This is in spite of no overall frequency dependent effect of EMG or performance responses across participants as a group. The influence of the role of expectancy effect appears minimal following this particular WBV protocol. 2. There was a significant effect of filter technique on EMG data recorded during vertical WBV. A tailored, WBV specific notch filter technique may offer an effective balance; excluding WBV noise artifacts without removing significant portions of valuable muscle signal EMG data. 3. The influence of external load on WBV acceleration output also appears minimal. Platform acceleration output was dependent on WBV frequency, as expected. Lower accelerations were recorded in superior body segments, suggesting a dampening mechanism, which was also proportionally dependent on frequency. EMG activity of upper and lower leg segments may differ in response to frequency, likely due to transmission distances involved. This may partially account for a potential dampening mechanism. In addition, a protocol to quantify WBV stimuli delivered by this particular WBV type illustrated significant differences in theoretical and actual parameters. This may explain not only the lack of overall explosive performance effect reported earlier; but also the inconsistent WBV literature. Future research should quantify WBV stimulus before investigating possible neuromuscular responses to individualised protocols, which may be assessed via EMG activity.

Herniation of the intervertebral disc is a pathological condition characterized by protrusion of the tissue posterio-laterally, often impinging on the spinal chord or nerve roots. The disease is accompanied by a reduction in the average molecular weight and viscosity of the disc proteoglycans, in excess of that which normally occurs with increasing age. The proteoglycans of disc however have not been examined in terms of the modern concepts of cartilage matrix structure. Bovine nasal cartilage, has been shown to contain proteoglycan aggregates, trapped in the intersticess of a collagen network, which can be dissociated with 4M guanidine hydrochloride into diffusible proteoglycan subunits and a multicomponent "linking" fraction. A similar system was thought to occur in the intervertebral disc. It seemed possible that, if such a system was present in the disc, the reduction in the molecular weight and viscosity of the proteoglycans with increasing age and herniation could be due to a decrease in proteoglycan aggregation. The present study showed that proteoglycan aggregates similar to those of bovine nasal cartilage are found in the human intervertebral disc, but that they only represent 5% of the total proteoglycans in the tissue. In contrast, bovine nasal cartilage contained 70% of the proteoglycans in the aggregated form. A novel modification of the extraction procedure was devised by which it was possible to assess the degree of proteoglycan aggregation. Sequential extraction of the tissue with a weak and strong electrolyte (0.4 M and 4M guanidine hydrochloride) selectively removed non-aggregated and aggregated proteoglycans respectively. This procedure provides a new and rapid method for assessing the degree of proteoglycan aggregation in a variety of connective tissues. The small proportion of aggregate in the disc was almost exclusively located in the annulus fibrosus. Re-aggregation studies suggested that both disc and cartilage contain two proteoglycans, only one of which is capable of forming aggregates. Examination of the proteoglycans in a limited number of discs suggested that the degree of aggregation did not change with increasing age. Since, in addition, aggregates represent only a small proportion of the disc proteoglycans, it appeared unlikely that a decrease in the degree of aggregation could account for the decrease in molecular weight and viscosity of the disc proteoglycans observed with increasing age and/or degenerative disc disease. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate