oam1998@outlook.com / Background: Obstructive sleep apnea (OSA) is associated with increased mortality, for which impaired functional capacity (IFC) has been established as a surrogate. We sought to assess whether IFC is associated with increased mortality in patients with OSA and whether IFC is predictive of increased mortality after accounting for coronary artery disease. Methods: Patients with OSA who underwent both polysomnography testing and exercise stress echocardiogram were selected. Records were reviewed retrospectively for demographics, comorbidities, stress echocardiographic parameters, and polysomnography data. Univariable and multivariable logistic regression analysis was used to evaluate the association between IFC and overall mortality. We then evaluated the variables associated with IFC in the overall population and in the subgroup with normal Duke treadmill score (DTS). Results: In our cohort, 404 (26%) patients had IFC. The best predictors of IFC were female sex, history of smoking, ejection fraction less than 55, increased body mass index, presence of comorbidities, abnormal exercise echocardiogram, abnormal heart rate recovery, and abnormal DTS. Compared with those without IFC, patients with IFC were 5.1 times more likely to die (odds ratio [OR], 5.1; 95% confidence interval [CI], 2.5–10.5; P , 0.0001) by univariate analysis and 2.7 times more likely to die (OR, 2.7; 95% CI, 1.2–6.1; P = 0.02) by multivariate analysis, when accounting for heart rate recovery, DTS, and sleep apnea severity. Among those without coronary artery disease, patients with IFC were at significantly increased risk of mortality (OR, 4.3; 95% CI, 1.35–13.79; P = 0.0088) compared with those with preserved functional capacity. Conclusions: In our OSA population, IFC was a strong predictor of increased mortality. Among those with normal DTS, IFC identified a cohort at increased risk of mortality.

[pt] Os projetos de capacidade de suporte de estacas estão baseados em dados de ensaio de campo de maneira direta ou indireta. Devido a sua praticidade, os métodos empíricos são amplamente utilizados. No Brasil os métodos de Decourt e Quaresma (1978, 1982) e de Aoki e Velloso (1975) se destacam. Este trabalho procura avaliar o uso de dados de SPT e CPT para estimativa de parâmetros geotécnicos necessários na previsão de capacidade de suporte de estacas através de métodos teóricos. São apresentadas e avaliadas formulações empíricas de estimativa de parâmetros para materiais granulares e materiais argilosos. Outro elemento importante na previsão da capacidade de suporte é o estado de tensões atuante em torno da estaca que é analisado através de considerações a respeito do coeficiente de empuxo. Finalmente, são mostrados alguns resultados de provas de carga para a análise da seleção de parâmetros e do estado de tensões, além de uma avaliação dos métodos empíricos de previsão de capacidade de suporte. / [en] The main objective of this thesis is to discuss the applicability of in-situ tests like the Standard Penetration Test (SPT) and the Cone Penetration Test (CPT) to determine directly the design parameters to predict the bearing capacity of pile foundations. In case it will be considered the use of empirical correlation to indicate the mechanical properties of the soil in terms of shear resistance, and the application of these values directly in the classic formulation based on the theory of equilibrium limit to evaluate distinctly the shaft and the base resistance of piles. Adaptations of these values will be proceeded considering aspects related with the non-linear behavior of the soil; the mechanism of load transfer and the influence of the constructive aspects.The results obtained through this new methodology will be compared with experimental results, obtained from static and dynamic load tests and also with other empiric procedures that use the results obtained from in-situ tests to evaluate directly the bearing capacity of deep foundations.

M.Com. (IT Management) / Vehicle traffic congestion on Gauteng’s metropolitan and national roads in South Africa remains a challenge, especially during peak hours and also when incidents occur. They hamper the flow of vehicle traffic. Traffic congestion has negative consequences for business and for commuters’ quality of life. The goal of this research project is to identify variables that influence the flow of traffic and to design a vehicle traffic prediction model which will predict the traffic flow pattern in advance, given a set of predictor variables that will enable motorists to make appropriate travel decisions ahead of time. The traffic flow was categorised into three classes, namely traffic jam, free flowing and flowing congestion. In this study, the artificial intelligence algorithms that include Bayesian Networks, K-Nearest-Neighbour, Multi-layer Perceptron (MLP) and C4.5 Decision Tree were used individually for predicting the vehicle traffic flow. The results obtained from these algorithms were compared using the predictive performance and prediction costs. The best predictive model is one that has lower cost and good performance. The results show that the MLP was the best performing algorithm in terms of predictive performance and low prediction costs. In order to predict a novel instance, a feed forward Multi-layer Perceptron network was built using Matlab and was used to predict the unseen vehicle traffic instance, also called a novel instance. The (MLP) model accurately predicts vehicle traffic flow on a single novel instance with a prediction performance of 80% (16 out of 20) on novel instances.

M.Cur. (Nursing Administration) / Please refer to full text to view abstract

Philosophiae Doctor - PhD / This study investigated, within the context of Brain Reserve Capacity (BRC) theory, whether repeated concussions resulted in residual deficits in cognitive and academic functioning of early adolescent rugby players relative to non-contact sports controls. / South Africa

Magister Artium (Psychology) - MA(Psych) / It is often assumed that postgraduate students and neophyte academics have the capacity to conduct research independently. Thus, upon qualification, it is expected of postgraduate students and academics to conduct research independently, publish their findings, meet publication targets and to supervise student research towards completion. However, the transition from postgraduate student or clinician to academia is considered very challenging as they are often not prepared for the multiple changes they will embark on upon entry into the Higher Education sector. As a result, various programmes and frameworks have been introduced to assist new academics in enhancing their research capacity. Such strategies included but were not limited to, writing retreats, peer monitoring, and dedicated time. However, these interventions reported on in literature are from primary sources and fail to comment on either the methodological rigour or the quality of the studies investigating these interventions. Thus there exists a gap in the literature for filtered information that has been systematically evaluated for methodological rigour and coherence. The present study aimed to establish an empirical base (filtered evidence) of literature reporting on strategies or interventions aimed at addressing research productivity in new academics. The study incorporated a systematic review methodology to identify appropriate literature for inclusion, evaluate literature for methodological quality and provide a meta-synthesis of the findings of included studies. The review considered studies, reporting on strategies or interventions with new academics during the period of 2000-2013. The review was conducted along three levels. Firstly, identification of potential titles, whereby keywords were combined and a comprehensive search of databases available at the University of the Western Cape library was initiated. Published research was also retrieved through mining the reference list of all included reports and articles. Secondly, a pair of reviewers worked together by screening the abstracts which were retrieved based on the titles identified, and thirdly, the abstracts that were successfully screened moved forward to full text reading. These studies were evaluated for methodological quality using the critical appraisal tool. Eligibility for inclusion was determined by a threshold score of 61%. As a result, the title search yielded a search result of 755, from these only 63 titles were selected for possible inclusion. The abstract screening resulted in the exclusion of 35 articles and 28 were included. After the critical appraisal, 15 articles were excluded. The findings of the present study revealed that there is good quality research on research capacity building for neophyte academics, as assessed on methodological rigour and coherence. Seven articles attained the threshold score (61% and above) for inclusion in the final summation and meta-synthesis. Evidence suggested that there are various interventions which have been implemented successfully to enhance research capacity building. The meta-synthesis revealed four core approaches to developing research capacity, namely mentoring approaches, theoretical formulations, research/evidence-based investigation as well as a multidimensional and integrated approaches. These approaches were aimed at bridging that gap between research and teaching and developing competent researchers. The core feature that emerged from these approaches was that successful or effective strategies have to include numerous components such as individual characteristics (motivation), effective leaders and institutional characteristics (rewards, incentives and resources). It was found that these components were integrated and often reciprocally influencing. Ethics clearance was obtained from the relevant committees at UWC. Furthermore, plagiarism and collaboration was taken into account as this study forms part of a larger project.

Magister Commercii - MCom / In Rwanda, there is a serious concern that the human resource capacities to formulate and implement policies and programmes and deliver quality services to meet the Government's development priorities are not only limited but are eroding as well, despite efforts to the contrary. The purpose of this study is to examine the challenges of Human Resource capacity building and retention in the Rwandan Public Sector. Specific objectives are (i) to identify the civil servants' perceived reasons that make them quit the public sector after acquiring the desired skills by their working institutions; (ii) to identify the civil servants' perceptions on the measures to improve capacity retention in Rwandan public sector; (iii) to review the capacity building and retention challenges facing the Rwandan public sector; (iv) to contextualize problems of capacity building and capacity retention within the broader literature; and (v) to make recommendations regarding the specific strategies the Rwandan Public Sector should adopt to retain civil servants. The study was carried out in Western Cape Province, at the Universities of University of the Western Cape (UWC), Cape Peninsula University of Technology (CPUT), University of Cape Town (UCT) and University of Stellenbosch (US). The eligible study participants were postgraduate Rwandan students pursuing masters and doctoral studies in various fields. A descriptive quantitative study design was used to collect data on the participants' perceived reasons as to why, after training, civil servants are likely to quit the public sector, together with the measures participants feel the Rwanda Public sector could put in place to retain the employees after training, as well as the human resource challenges facing Rwandan public sector. All 40 Rwandan postgraduate students pursuing masters and doctoral studies at the selected universities (based on Rwandan Embassy Records for 2010) were the sample for this study, and there was a 100% response rate. A structured self-administered, close-ended and pre-coded questionnaire was used to collect data. Data was analysed using the SPSS software programeme, and descriptive statistics were used to describe various variables to answer the research questions. With regard to research ethics permission was granted by the Higher Degrees Committee of UWC and ethical clearance was obtained from the Research Grants and Study Leave Committee at UWC. Permission to conduct the study among Rwandanmasters and doctoral students on capacity building programmes supported by the Government of Rwanda was granted by the Rwandan Embassy. The purpose of the study was explained to the participants using the participants' information sheet. Signed informed consent both written and verbal was obtained from each individual participant. Participation was voluntary, anonymity of participants was assured, participants information was kept confidential and voluntary withdraw from the study at any time was guaranteed to participants. The findings demonstrate that 45% of the respondents do not intend to continue working in the Public Sector after training due to both financial considerations and workplace working conditions.The findings also indicate that 55% of the respondents intend to work in the public sector after training. The research recommends, amongst other things, that a larger survey be conducted among Rwandan students on study abroad programmes to ascertain if the reasons for quitting and perceived measures to remain in the public sector after training hold for all the civil servants on capacity building programmes.

Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / This thesis examines the effect of off-farm income on a farming operation’s ability to repay their debt. The thesis develops a regression model that includes net farm income, debt repayment capacity with carryover working capital, off-farm income sources and a number of other independent variables that help define each individual borrower. The model provides an evaluation of the current farming environment and examines various income opportunities available to borrowers affects repayment capacity. This study found that the presence of off-farm income can increase the probability that the operation will be able to repay their debts. The model indicates that if off-farm income is present, the borrower’s debt repayment capacity ratio increases. This thesis further explores the model and the results produced from not only off-farm income but several different variables within the borrower’s scope of business. Results suggest that many other factors that are not available in the sample also play a large role in predicting an operation’s ability to repay debt. The study determined that the presence of one source of off-farm income was positive and statistically significant in explaining repayment capacity. An operation with a strong outside income source and one spouse working full time on the farm is more financially stable and will likely be more successful at repaying their debts.

This study, undertaken under the auspices of the Centre of Wildlife Management and the former Centre for Indigenous Knowledge (University of Pretoria) was conducted in Maputaland, with special reference to the Tembe Elephant Park, Sileza Nature Reserve and in the neighbouring traditional wards (izigodi) of Mbangweni, Bhekabantu, Kwandaba, Zama-zama, Tsokotho, Manqakulani (which includes the Tshanini Community Conservation Area), Lulwane, Mntikini, Ndlondlweni, Ndovu and Sibonisweni. The main objective of this study was to evaluate the range condition and grazing capacity of the natural veld. A management plan for the Tshanni Community Conservation Area is presented, which could potentially serve as template for similar areas. To accomplish these objectives a cattle as well as a vegetation survey were conducted. The cattle surveys were conducted among the local communities (mentioned above) to identify and to evaluate the role played by cattle in the everyday lives of the communual people and to identify the types of grazing regime (practices). The vegetation surveys were undertaken to evaluate the range condition, grazing capacity and grazing quality of the herbaceous vegetation. The study also included methods to determine the number, distribution and health status of cattle present in the study area. The results indicated that social and religious values that were associated with cattle in the older Zulu culture have clearly faded in the Tembe Traditional Area. The current values of local communal people regarding cattle were concentrated on utilization and investment for future uncertainties. Cattle were still seen as wealth and status symbols in the local communities and were highly prized possessions if they could be obtained. The official cattle numbers did not seem to reflect the actual cattle numbers in the study area at the time of study. It was also clear that cattle were distributed in areas where the water supply was sufficient. The main grazing areas were thus in the east of the study area in the hygrophilous vegetation to the east of Manqakulani and mainly in Ndlondlweni. No specific grazing management practices could be identified and the grazing system could be best described by a continuous grazing practice. Grazing was not restricted to any part or piece of land inside the specific isigodi as long as the cattle stayed out of other people’s cultivated land. Overstocking the grazing area was not occurring at the time of the study as the stocking density was well below the area’s capacity. The general perception of the majority of the cattle owners was that their cattle were in a good condition. An analysis of the results obtained from the vegetation survey indicated that the herbaceous biomass yield did not vary noticeably among the management units within a site as well as among the different sites. The small fuel loads in the Tshanini Community Conservation Area did not necessitate burning and were probably below fuel loads needed for fires to spread. However, it was frequently observed that fire could be maintained in areas where the herbaceous biomass yield was below 2 000 kg/ha. The results represented in this study also indicated that the management units of the Tshanini Community Conservation Area were generally in a good condition and that the range condition of the Tshanini Community Conservation Area compared relatively well with the other reserves in the study area. The modified Ecological Index Method was reliable and time saving, yet simplistic enough for assessing the range condition of the management units of the Tshanini Community Conservation Area and the entire Tembe Traditional Area. The stocking density must be adaptable and based on the quantity and quality of grazing available at any time. The model that was used to calculate the stocking density of the study area allows for several elements to be modified to suit the conditions on a particular wildlife reserve at a particular time. For example, in future it may become necessary to adjust the percentage composition of graze and browse in the diet of some animal types for the calculation of Grazer Units (GU) and Browser Units (BU), mainly because the diet of the same type of animal may vary regionally. Finally, changes in the choice of the types of wildlife can be accommodated depending on the preferences and objectives of the management and steering committee of the Tshanini Community Conservation Area. This model can be applied as a tool for active adaptive management because it allows more control over the quantity and quality of available food plant resources and hence the stocking density of animal resources. It is proposed that the results of the present study be combined and integrated into a Geographic Information System (G.I.S.) database that could form the ecological basis for future management planning of the Tembe Traditional Area as part of the Usuthu-Tembe-Futi Transfrontier Conservation Area. / Dissertation (MSc)--University of Pretoria, 2009. / Animal and Wildlife Sciences / unrestricted

No abstract available. / Dissertation (LLM)--University of Pretoria, 2013. / Centre for Human Rights / unrestricted