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A framework for the delivery of quality physical education and school sport in the South African public-school system
Get PDFAbstract: UNESCO’s charter on physical education physical activity and sport (1978) (UNESCO 2019c) was revised in 2013 to declare that participation in physical education and sport was a fundamental human right. Free basic and further education for everyone is enshrined within the South African Constitution’s Bill of Rights. In 2016, 9,722,965 learners were in public schools receiving funding from the state. However, not all have access to quality physical education (QPE) or the opportunity to participate in school sport. The aim of the study is to develop a framework for the effective delivery of quality physical education and school sport (PESS) in the South African public school system to maximise its role in delivering on outcomes of national development goals. By utilising a social justice theoretical framework, the study investigates the factors that influence the practices manifesting within schools. Making use of a mixed a mixed-method research approach, data was collected from 53 schools across the country via questionnaires; by interviews held with principals (n=17) and sport directors (n=18); and 15 focus groups with educators (n=64) and 10 focus groups with learners (n=48) in 29 schools in the Eastern Cape, Gauteng, KwaZulu-Natal and the Western Cape. Data was coded and the influencing factors were grouped into three emerging themes: context, policy and strategy, and resourcing. This study offers and abstract and objective overview and reflection by going beyond simply reporting the state and status of PESS. Looking holistically at the contextual situation and the systemic issues that affect the delivery of PESS at all levels, the research found that international discourses in policies relating to international development translate to national transformative intentions in a myriad of complex ways. This policy framing from an international perspective is filtered through structures and systems to constitute certain practices in certain local contexts. However, South African policies governing PESS are crowded, fragmented and dysfunctional in its articulation with practices as government institutions are not sufficiently aligned to enable a greater sophistication of policy making and/or ensure consistency of policy uptake at the grass roots level to deliver quality PESS. iv The Practice Model provides a social justice framework for policymakers to understand the relationships between the influencing factors, the impact of international forces on policy, the social structures of society and how they manifest within physical education and sport. These key considerations are required for reform in determining legislation, delivery strategies, and how to determine the successful delivery of, and access to, quality physical education (QPE) and school sport (SS). Until the policy sectors are aligned meaningfully, there is a threat to the future and quality of PESS in South Africa.D.Phil. (Sport Management
Long-dated interest rate modelling
Get PDFAbstract: In this thesis, we consider problems in long-dated interest rate modelling, with particular focus on the forward-LIBOR market model (LFM) and its displaced diffusion extension, known as the displaced lognormal forward-LIBOR model (DLFM). We provide swaption volatility approximations for longer maturities and tenors that strike a balance between efficiency and accuracy when compared to the Rebonato, Hull-White and Kawai methods. Our approximations depend on a mean-update of the underlying jointly-distributed forward-LIBOR rates for which we use a multi-dimensional weak order 2.0 It¯o-Taylor scheme. The higher order scheme more accurately captures the state dependence present in the LFM dynamics. Furthermore, we develop an algorithm under the DLFM to approximate moments of the jointly-distributed forward-LIBOR rates based on a lognormal assumption. This algorithm is an iterative procedure that consists of a multi-dimensional full weak order 2.0 It¯o-Taylor expansion and a second-order Delta method that reincorporates state information that is normally frozen at a previous state. This combination more effectively captures the state dependence present in the dynamics of the DLFM. Lastly, we introduce a diagnostic tool in the form of a quantile approximation under the DLFM to analyse the behaviour of the jointly distributed long-dated forward-LIBOR rates. This is useful since the class of forward-LIBOR market models can produce unrealistically high forward rates under certain volatility parametrisations, particularly for maturities beyond liquid market calibration instruments. We further explore a methodology to keep these rates within realistic limits. All our approximations are extensively benchmarked using quasi-Monte Carlo (QMC) simulations and shown to improve upon previous approaches.Ph.D. (Mathematical Statistics
Sample preparation methodologies for preconcentration of selected emerging contaminants in environmental samples
Get PDFAbstract: The presence of pharmaceutical residues in the environment waters is a serious concern because of the possible ecotoxicological impacts related to long-term exposure of both terrestrial and aquatic ecosystem. Pharmaceuticals end up into the influent wastewater mainly through the domestic sewage system, hospital disposal of wastes, unused and expired drugs and agricultural activities. Most conventional wastewater treatment plants are not capable of efficiently removing pharmaceutical residues from wastewater before discharging effluents into the environment. This is mainly due to the presence of very low concentrations of pharmaceutical residues as well as their diverse chemical structures, modes of action and other properties. Despite the low concentrations of pharmaceutical residues in the environment, their individual toxicities as well as their combinational effects have shown to have detrimental health effects on terrestrial and aquatic organisms. However, there are no maximum discharge guidelines and standards yet, which regulates the discharges and presence of these pollutants in the environmental matrices. Therefore, it is imperative to monitor their concentrations in environmental waters to avoid health effects due to unexpected exposures of humans and other living organisms. In view of the above, the main aim of this study was to develop sample preparation methods for sample clean-up, extraction and preconcentration of pharmaceutical residues, specifically, non-steroidal antiinflammatory drugs and antiretroviral drugs in river water and wastewater matrices. This was achieved by developing four sample pre-treatment techniques which include two magnetic solid phase extraction (MSPE) methods, dispersive microsolid phase extraction (D-μSPE) and supramolecular solvent based dispersive liquid-liquid microextraction (SSDLLME). The quantification of the selected pharmaceuticals was achieved by high performance liquid chromatography equipped with diode array detector (HPLC-DAD)...Ph.D. (Chemistry
Performance evaluation of functionalized carbon aerogel as oxygen reduction reaction electrocatalyst in zinc-air cell
Get PDFAbstract: The comparable catalytic activities of non-noble metal electrocatalysts are the prime to enable their breakthrough performances for oxygen reduction reaction (ORR). In this work, the nitrogen-doped carbon aerogels were strategically functionalized with Ce/Fe elements. The increased content of pyridinic nitrogen from 16.71% to 20.28% coupled with a macro-porous structure resulted in an enhanced ORR catalytic performance. The performance evaluation showed that the ORR onset potential of the functionalized sample shifted from 0.893 V to 0.968 V comparing to the unfunctionalized sample. The open cell voltage reached 1.450 V when the optimal..
Self-employment through ride-hailing : drivers’ experiences in Johannesburg, South Africa
Get PDFAbstract: Orientation: Ride-hailing services have gained popularity in South Africa because of their ability to provide a reliable alternative to traditional modes of transport. However, little is known about ride-hailing drivers. Research purpose: The purpose of this study was to determine the ride-hailing drivers’ job satisfaction levels and the challenges they experienced. Motivation for the study: This study was motivated by the lack of scholarly information on the experiences of drivers involved in ride-hailing in the context of South Africa. Research design, approach and method: This study adopted a pragmatic approach through a mixed-method, survey-based design. Fifty-three ride-hailing drivers were randomly interviewed in Johannesburg, South Africa, using a pre-designed and piloted questionnaire. Data were analysed using methods of descriptive interpretation and inductive thematic analysis. Main findings: A descriptive statistical analysis showed that most ride-hailing drivers provide the service to earn their primary income. Furthermore, a thematic analysis found that ridehailing drivers felt unsafe providing these services because of the violence they experienced from minibus taxi operators in the region..
COVID-19 burial guidelines in Indigenous Knowledge Systems (IKS)
Get PDFAbstract: The COVID-19 pandemic has had a considerable impact on mundane daily tasks and significant cultural practices, including funerals and burials. Growing up, I observed that death in my family is a well-respected cultural process. It is believed that those who departed into the spirit world will be joining the living dead in the afterlife. For the deceased to be welcomed into the spirit world in the traditional sense, families perform specific rites of passage rituals during the burial. This is an important exercise to avert the wrath of the spirit world on the bereaved family. Attention to detail during these rituals is vital to assist the bereaved family in expressing their grief while simultaneously showing respect to the spirit world. As a non-practising sangoma, I had observed traditional funeral and burial processes long before the outbreak of the pandemic and understood their importance. While the pandemic shook traditional burial processes and made some rituals impossible, I found comfort in the knowledge that indigenous knowledge systems (IKS) could be used to appease the spirit world. In this article, I explain how IKS can assist bereaved families during funerals and burials to avert the wrath of the spirit world and find closure
A pilot-study of the use of nutrition-related Apps and Software in Africa during the COVID-19 pandemic
Get PDFAbstract: The ongoing COVID-19 pandemic and the associated lockdown measures have risen the malnutrition problem in the world, especially in Africa. The use of nutrition apps/software at individual level therefore appears as suitable solution given the context. This study aimed at assessing the actual usage level of nutrition apps/software and the determining factors. A cross-sectional study consisting of an online-survey conducted from April to May 2020 with as target Africans aged of 18 and above was carried out. A total of 460 respondents from different African countries was registered. Globally they appeared to have started using computer and smartphones since at least 5 years and this mostly at a daily frequency together with internet. A total of 52.2 % of the respondents recognized not to apply or not to know if they apply the principles of a balanced diet in their day-to-day life, but just 18% reported to be using a nutrition apps/software; COVID-19 pandemic having pushed 7% to refer more to these tools and 0.7% to start using one. South Africa nationals, people living in a household of 3-5 people and those having a monthly income above 500 USD tended to use them more. Almost half of the users report that these tools do not take into consideration foods available in their context. On the other hand, almost half of the non-users (41.5% of respondents) said they would prefer to be advised by a dietician. However up to 50.9% clearly stated they are interested in learning more about these tools, which is of quite of big interest in preventing Non-communicable diseases resurgence in relation to COVID-19 pandemic
Food security in urban cities : a case study conducted in Johannesburg, South Africa
Get PDFAbstract: The objectives of the study were to determine the prevalence of food insecurity in greater Johannesburg metropole (South Africa). A total of 1000 households were interviewed using standardised food insecurity scaling and scoring metrics. Findings revealed that 34% of households experienced food insecurity and almost 60% spent R1000($57) or less on food per month. Only half of respondents reported adequate food provisioning throughout the year. Many households frequently bought less preferred foods or only what was necessary and almost 50% borrowed food or money to cope with food insecurity. Appropriate interventions to alleviate food and nutrition security are essential
An evaluation of interpolation techniques and commonly used digital elevation models for floodline mapping in a South African environment
Get PDFAbstract: Flooding accounts for a large proportion of property loss and damage all over the world. Flood frequencies associated with intense periods of rainfall show increasing trends in both South Africa and globally. As a result, preventative measures to mitigate property loss and damage play an increasingly important role in the built environment. In hydrology terms, flood-lines refer to the maximum extent of a flood event that can either be measured retrospectively after a rainfall event of significance through in-situ measurements or proactively simulated through a digital representation of the assessment area. The proactive approach has inherent benefits of being able to run a multitude of volumes to illustrate the effect of various rainfall events on a river system but is dependent on the quality of data being fed into the system itself. A key component to the data input includes elevation information that defines the topographical environment around the river system. There are several elevation sources and methods of interpolating to create continuous elevation surfaces that can be utilized for an area-based flood modelling scenario. The usage and application of many of these sources are affected by the cost and time factors which often place restrictions on the level of detail and accuracy that the digital representation of the river system captures. Due to the multitude of variables with regards to the elevation data inputs, there is a need to 1) identify the best-suited interpolation techniques to accurately represent a hydrological environment; and 2) to identify an optimal elevation source to accurately depict a flood-line output...M.Sc. (Geography
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