4. Electronic Theses and Dissertations (ETDs) - Faculties submissions

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Prevalence and factors of HIV associated Oral Kaposi Sarcoma at Wits Oral Health Centre, Johannesburg
(University of the Witwatersrand, Johannesburg, 2024-07) Chetty, Hasita; Padayachee, Sankeshan; Mafojane, Tumane
Introduction: HIV associated Oral Kaposi Sarcoma (OKS) is a neoplasm predominantly occurring in immunocompromised patients. Therefore, it is often observed in an HIV positive and AIDS population (Moore & Chang, 2003). KS is caused by the Kaposi Sarcoma Herpes Virus (KSHV) or Human Herpes Virus-8 (HHV8) (Naidoo et al, 2016). The risk of acquiring KS increases in the presence of HIV infection and immunosuppression (Kamulegeya & Kalyanyama, 2008). HIV-KS can occur at any stage of HIV infection but has been more prevalent at the stage of AIDS or severe immune impairment (Khammissa et al., 2012). Both HHV8 infection and HIV/AIDS are highly prevalent in Africa (Kamulegaya and Kalyanyama, 2008). There is a lack of current evidence documenting the relationship between HIV/AIDS and OKS since the implementation of ART, therefore this study intends to augment the existing literature. This study aimed to determine the prevalence and factors of HIV associated OKS, on histopathologically diagnosed patients attending the WITS Oral Health Centre, Johannesburg, between 2008 and 2018. This period predates and postdates the roll out of ART in the South African public health sector in 2012 and speaks to the relationship between ART and the occurrence of HIV associated OKS. Materials and Method: This is a cross-sectional study using records from the Wits Oral Health Centre (WOHC) and National Health Laboratory Service (NHLS). The study period is 10 years from January 2008 to December 2018. Prevalence of OKS was calculated based on patients with a positive histopathological diagnosis of OKS within the study period from the NHLS database. Ethical Considerations: Permission was requested from the Academic Affairs and Research Management System (AARMS) National Health Laboratory Service (NHLS) and WOHC to access patient files. Records of patients with a positive OKS histopathological diagnosis were noted. They were allocated a study number and patient number on a data sheet. The corresponding patients’ files were accessed from WOHC to attain further information (as per the data sheet). Patient confidentiality was be maintained as no names were recorded and files were allocated a number for cross-referencing between NHLS and WOHC data. Ethics clearance was attained from the Wits Human Research Ethics Committee to carry out this study. Results: The prevalence of OKS that was found in this population (137679 patients seen at WOHC) was 0.017432%(n=24). There were more females that presented with OKS than males. The mean age of presentation was 39.11 years of age (SD 12.459). There was a significant relationship between high viral loads and a low CD4 count. The palate was the site most frequently biopsied in diagnosed OKS cases. Conclusion: The prevalence of OKS over the study period was very low. The mean age of OKS presentation was 39.21 years of age. More females presented with HIV associated OKS than males and the palate was the site, from which most biopsy samples were taken in OKS diagnoses. There is a significant relationship between high viral loads and low CD4 cell counts. This study is suggestive that a possible reason for the low number of OKS cases could be administration of ART by state institutions in South Africa, this can be further investigated to establish the effect of ART on OKS.
Occupational exposure to chemicals, and health outcomes, among nail technicians in Johannesburg, South Africa
(University of the Witwatersrand, Johannesburg, 2023-08) Keretetse, Goitsemang; Brouwer, Derk H.; Nelson, Gill
Introduction: Nail technicians are exposed to chemicals emitted from activities performed in nail salons, including simple buffing of nails, basic manicures and pedicures, application of nail polish, and the application and sculpting of artificial nails. The various products used during these processes may contain volatile organic compounds (VOCs), which pose a health risk to both the nail technicians and their clients. Associated health effects include skin, eye, and respiratory irritation, neurologic effects, reproductive effects, and cancer. The aim of this study was to effects within the formal and informal sectors in Johannesburg, South Africa. In this study, informal nail technicians are defined as those working in nail salons that are not licensed or registered with any formal enterprise or establishment, or in their own capacity. The objectives were 1) to estimate the prevalence of self-reported symptoms associated with the use of nail products, 2) to measure exposures to chemicals in nail products used in the formal and informal nail salons, 3) to investigate the feasibility and reliability of self-assessment of exposure as a method of estimating exposure to chemicals, and 4) to investigate the association between respiratory symptoms (chronic and acute) and chemical exposures in both formal and informal nail technicians. Methods: This was a cross-sectional study. A questionnaire, adapted from other studies, was piloted before being administered to the participating nail technicians. Data were collected from 54 formal and 60 informal nail technicians, regarding sociodemographic characteristics, perceptions of working with nail products, and self-reported symptoms of associated health effects. A subset of 20 formal and 20 informal nail technicians was conveniently selected from the 114 participants for the exposure assessment phase. The two groups were further divided into two groups of 10 for the controlled/expert exposure assessment (CAE) and the self-assessment of exposure (SAE). Personal 8-hr exposure measurements were performed using VOC and formaldehyde passive samplers attached to the participant’s breathing zone over three consecutive days. For the SAE approach, participants conducted their own exposure measurements, while the CAE approach was fully conducted by the principal researcher. Task-based measurements were carried out using a photoionization detector (PID) to measure peak concentrations during specific nail application activities. A probabilistic risk assessment was conducted to estimate the carcinogenic and non-carcinogenic life time risks from exposure to VOCs. Chemical analysis was conducted by a SANAS-accredited laboratory. After correcting for their respective evaporation rates, relative to the evaporation rate of d-limonene (the VOC with the lowest evaporation rate), the adjusted total VOC (TVOC) concentrations were calculated using the 13 VOCs that were detected at a frequency of 30% or more. VOC concentration data below the limit of detection (LoD) were imputed, using the regression on order statistic (Robust ROS) approach. The self-reported symptoms were categorised into neurological effects, respiratory effects, eye irritation, and skin irritation. The ACGIH additive effects formula was used to calculate the combined respiratory effect of selected VOCs. Different statistical tools were used to analyse the data for each objective. Results: Formal and informal nail technicians used different nail products, performed different nail applications, serviced different mean numbers of clients, and were exposed to different concentrations of selected VOCs. Acetone concentrations were higher in formal nail salons, due to the soak-off method used for removing existing nail applications, while methyl methacrylate (MMA) concentrations were higher in informal nail salons - related to acrylic methods being used more frequently in the informal than the formal nail salons. All VOC concentrations were below their respective occupational exposure limits, with the exception of formaldehyde (0.21 mg/m3). TVOC levels were higher in formal nail salons, due to the bystander effect from multiple nail technicians performing nail applications simultaneously. Sixty percent of the informal nail technicians reported health-related symptoms, compared to 52% of the formal nail technicians, and informal male nail technicians reported more symptoms than their female counterparts. All nail technicians' median and 95th percentile non-cancer risks exceeded the acceptable risk of 1 for xylene, 2-propanol, and benzene, while the cancer risk estimates (medians and 95th percentiles) for benzene and formaldehyde exceeded the US EPA cancer risk threshold of 1 x 10-6. Conclusion: This is the first study to assess exposures to VOCs in the often-overlooked informal sector and compare these exposures with those in the formal sector of the nail industry. Personal breathing zone concentration data for nail salon workers were generated in this study, including the informal sector, which is always challenging to access for research. Although banned in many countries, MMA is still used in South Africa in the informal nail sector. The SAE study showed that participatory research is feasible and enables a more reliable estimate of the exposure by expanding the amount of data. Using a combination of shift and task-based measurements was particularly effective in creating exposure profiles of employees and identifying activities that require targeted interventions. There is a need for the nail industry, especially the informal salons, to be more closely regulated, concerning the hazardous chemicals frequently encountered in nail products. Nail salons should reduce exposure frequency by regulating working hours, making informed decisions regarding the procurement of nail products, and adopting safe work practices to reduce emissions from harmful chemicals and thus exposure among nail salon workers and their clients.
Preventing Coal Mine Dust Lung Disease: Application of Bayesian Hierarchical Framework for Occupational Exposure Assessment in The South African Coal Mining Industry
(University of the Witwatersrand, Johannesburg, 2023-10) Made, Felix; Brouwer, Derk; Lavoue, Jerome; Kandala, Ngianga-Bakwin
Background: The world's largest energy source is coal with nearly 36% of all the fuel used to produce power. South Africa is the world's top exporter and the seventh-largest producer of coal. In the upcoming years, it is expected that South Africa's coal production output rate will rise. Coal mine dust lung disease (CMDLD) is an irreversible lung disease caused by the production of coal, the emission of dust, and prolonged exposure to the dust. When conducting safety evaluation, exposure is typically reported as an eight-hour time-weighted average dust concentration (TWA8h). In occupational exposure contexts, occupational exposure limits (OEL) are often used as a threshold where workers can be exposed repeatedly without adverse health effects. The workers are usually grouped into homogenous exposure groups (HEGs) or similar exposure groups (SEGs). In South Africa, a HEG is a group of coal miners who have had similar levels and patterns of exposure to respirable crystalline silica (RCS) dust in the workplace. Several statistical analysis methods for compliance testing and homogeneity assessment have been put into use internationally as well as in South Africa. The international consensus on occupational exposure analysis is based on guidelines from the American Industrial Hygiene Association (AIHA), the Committee of European Normalisation (CEN), and BOHS British and Dutch Occupational Hygiene Societies' guidelines (BOHS). These statistical approaches are based on Bayesian or frequentist statistics and consider the 90th percentile (P90) and 95th percentile (P95), with- and between-worker variances, and the lognormal distribution of the data. The current existing practices in South Africa could result in poor or incorrect risk and exposure control decision-making. Study Aims: The study aimed to improve the identification of coal dust overexposure by introducing new methods for compliance (reduced dust exposure) and homogeneity (similar dust exposure level) assessment in the South African coal mining industry. Study Objectives: The objectives of this study were: 1. To compare compliance of coal dust exposure by HEGs using DMRE-CoP approach and other global consensus methods. 2. To investigate and compare the within-group exposure variation between HEGs and job titles. 3. To determine the posterior probabilities of locating the exposure level in each of the OEL exposure categories by using the Bayesian framework with previous information from historical data and compare the findings and the DMRE-CoP approach. 4. To investigate the difference in posterior probabilities of the P95 exposure being found in OEL exposure category between previous information acquired from the experts and the current information from the data using Bayesian analysis. Methods: The TWA(8h) respirable coal dust concentrations were obtained in a cross-sectional study with all participants being male underground coal mine workers. The occupational hygiene division of the mining company collected the data between 2009 and 2018. The data were collected according to the South African National Accreditation System (SANAS) standards. From the data, 28 HEGs with a total of 728 participants were included in this study. In objectives 1 and 2, all 728 participants from the 28 HEGs were included in the analysis. For exposure compliance, the DMRE-CoP accepts 10% exceedance of exposure above the OEL (P90 exposure values from HEGs should be below the OEL). The 10% exceedance was compared to the acceptability criterion from international consensus which uses 5% exceedance above the OEL (P95 exposure is below the OEL) of the lognormal exposure data. For exposure data to be regarded as homogenous, the DMRE-CoP requires that the arithmetic mean (AM) and P90 must fall into the same DMRE-CoP OEL exposure category. The DMRE-CoP on assessment of homogeneity was also compared with the international approaches which include the Rappaport ratio (R-ratio) and the global geometric standard deviation (GSD). A GSD greater than 3 and an R-ratio greater than 2 would both indicate non-homogeneity of the exposure data of a HEG. The GSD and DMRE-CoP criteria were used to assess the homogeneity of job titles exposure within a HEG. In objective 3 a total of nine HEGs which have 243 participants, were included in the analysis. To investigate compliance, a Bayesian model was fitted with a Markov chain Monte Carlo (MCMC) simulation. A normal likelihood function with the GM and GSD from lognormal data was defined. The likelihood function was updated using informative prior derived as the GM and GSD with restricted bounds (parameter space) from the HEGs' historical data. The posterior probabilities of the P95 being located in each DMRE exposure band were produced and compared with the non-informative results and the DMRE approach DMRE-CoP using a point estimate inform of the 90 percentiles. In objective 4, a total of 10 job titles were analysed and selected. The selection of the job titles was based on if they have previous year's data so it can be used to develop prior information in the Bayesian model. The same job titles were found across different HEGs, so to ensure the mean is not different across HEGs, the median difference of a job title exposure distribution across HEGs was statistically compared using the Kruskal-Wallis test, a non-parametric alternative to analysis of variance (ANOVA). Job titles with statistically non-significant exposure differences were included in the analysis. Expert judgements about the probability of the P95 located in each of the DMRE exposure bands were elicited. The IDEA (Investigate", "Discuss", "Estimate" and "Aggregate) expert elicitation procedure was used to collect expert judgements. The SHELF tool was then used to produce the lognormal distribution of the expert judgements as GM and GSD to be used as informative prior. A similar Bayesian analysis approach as in objective 3 was used to produce the probability of the P95 falling in each of the DMRE exposure bands. The possible misclassification of exposure arising from the use of bounds in the parameter space was tested in a sensitivity analysis. Results: There were 21 HEGs out of 28 in objectives 1 and 2 that were non-compliant with the OEL across all methods. According to the DMRE-CoP approach, compliance to the OEL, or exposure that is below the OEL, was observed for 7 HEGs. The DMRE-CoP and CEN both had1 HEG with exposures below the OEL. While the DMRE-CoP showed 6 homogeneous HEGs, however, based on the GSDs 11 HEGs were homogeneous. The GSD and the DMRE-CoP agreed on homogeneity in exposures of 4 (14%) HEGs. It was discovered that by grouping according to job titles, most of the job titles within non-homogenous HEGs were homogenous. Five job titles had AMs above their parent HEG. For objective 3, the application of the DMRE-CoP (P90) revealed that the exposure of one HEG is below the OEL, indicating compliance. However, no HEG has exposures below the OEL, according to the Bayesian framework. The posterior GSD of the Bayesian analysis from non-informative prior indicated a higher variability of exposure than the informative prior distribution from historical data. Results with a non-informative prior had slightly lower values of the P95 and wider 95% credible intervals (CrI) than those with an informative prior. All the posterior P95 findings from both non-informative and informative prior distribution were classified in exposure control category 4 (i.e., poorly controlled since exceeding the OEL), with posterior probabilities in the informative approach slightly higher than in the non-informative approach. Job titles were selected as an alternative group to assess compliance in objective 4. The posterior GSD indicated lower variability of exposure from expert prior distribution than historical data prior distribution. The posterior P95 exposure was very likely (at least 98% probability) to be found in exposure control category 4 when using prior distribution from expert elicitation compared to the other Bayesian analysis approaches. The probabilities of the P95 from experts' judgements and historical data were similar. The non-informative prior generally showed a higher probability of finding the posterior P95 in lower exposure control categories than both experts and historical data prior distribution. The use of different parameter values to specify the bounds showed comparable results while the use of no parameter space at all put the posterior P95 in exposure category 4 with 100% probability. Conclusions: In comparison to other approaches, the DMRE-CoP tend to show that exposures are compliant more often. Overall, all methods show that the majority of HEGs were non-compliant. The HEGs that suggest non-homogeneity revealed that the constituent job titles were homogenous. Application of the GSD criterion indicated that HEGs are more likely to be considered as homogeneous than when using the DMRE-CoP approach. When using the GSD and the DMRE-CoP guidelines, alternative grouping by specific job titles showed a greater agreement of homogeneity. The use of job titles showed that using HEGs following the DMRE-CoP current guidelines might not show high-exposure job titles and would overestimate compliance. Additionally, since job titles within a HEG may be homogeneous or have a different exposure to the parent HEG, exposure variability is not properly recorded when using HEGs. In compliance assessment, it is important to use the P95 of the lognormal distribution rather than the DMRE-CoP approach that use the empirical P90. Our findings suggest that the subgrouping of exposure according to job titles within a HEG should be used in the retrospective assessment of exposure variability, and compliance with the OEL. Our results imply that the use of a Bayesian framework with informative prior from either historical or expert elicitation may confidently aid concise decision making on coal dust exposure risk. Contrary to informative prior distribution derived from historical data or expert elicitation, Bayesian analysis using the non-informative uniform prior distribution places HEGs in lower exposure categories. Results from noninformative prior distributions typically show high levels of uncertainty and variability, so a decision on dust control would be reached with less confidence. The Bayesian framework should be used in the assessment of coal mining dust exposure along with prior knowledge from historical data or professional judgment, according to this study. For exposure, findings are to be reported with high confidence and for sound decisions to be reached about risk mitigation, an exposure risk assessment should be considered while using historical data to update the current data. The study also promotes the use of experts in situations where it is necessary to combine current data with historical data, but the historical data is unavailable or inapplicable.
Investigating the effectiveness of a blended professional development intervention in improving the teaching of Physical Sciences: A study of novice teachers in South African rural schools
(University of the Witwatersrand, Johannesburg, 2024) Radebe, Nomfundo Knowledge; Mushayikwa, Emmanuel
Professional development is a cornerstone in shaping the teaching practice of novice teachers as well as those teachers who are teaching subjects they are not qualified to teach (off-field teachers). However, such support is scarce in rural schools because of the shortage of qualified teachers and geographical constraints, leaving teachers with two options, either to sink or swim, particularly in getaway subjects such as Physical Sciences. This is possible because Physical Sciences has fewer teachers graduating each year and is most likely being taught by off-field and novice teachers due to the lack of desired posts in other schools besides those in rural areas. As such, a blended professional development intervention for Physical Sciences teachers in a circuit consisting of rural schools in Mpumalanga province was administered by another study (referred to as larger study). This province was selected because of the persisting poor performance in Physical Sciences. The intervention was blended because it consisted of online and face-to-face teacher workshops, using the training model from the transmissive category of professional development aimed at transmitting information. The blended nature of the professional development intervention also emanates from the utilisation of WhatsApp, an online tool, to establish a community of practice, promoting collaboration amongst teachers and facilitators. The aim of the intervention was to shape the teaching practices of the Physical Sciences teachers in the circuit. It was also aimed at helping the teachers improve the performance of their learners by sharing with them skills they can use to prepare their learners for examinations. However, research has shown that professional development initiatives tend to fail to meet their intended objectives, exacerbating the need for its effectiveness to be continuously determined. Given this background, this study examined the effectiveness of the intervention in shaping the teaching practice of novice teachers only due to the challenges they experience as outlined above. The novice teachers were defined as teachers with less than five years of experience teaching Physical Sciences, inclusive of off-field teachers. A total of three novice teachers, out of thirteen Physical Sciences teachers, were available in the circuit and participated in the intervention. Two of these novice teachers (Mr Jones and Mr Smith) were not qualified to teach Physical Sciences unlike Mr Brown. In addition, Mr Smith has been teaching Mathematics for sixteen years and had only two years’ experience in teaching Physical Sciences. Page | XXI To determine the effectiveness of the intervention, the following research questions were answered: (1) What are the teaching and learning needs of novice Physical Sciences teachers in the rural schools of Mpumalanga province? (2) What are the views of the novice Physical Sciences teachers about the effectiveness of the blended professional development intervention workshops? (3) In what ways have the teaching practices of Physical Sciences novice teachers changed after participating in a blended professional development intervention? (4) How were the identified teaching and learning needs of novice Physical Sciences teachers in the rural schools of Mpumalanga addressed by the blended professional development intervention? As such, two lessons per teachers were observed before and after they participated in the intervention. Semi- structured interviews were conducted with the teachers individually before and after participating in the intervention. Furthermore, field notes were written down during the intervention workshops. Triangulation of data methods and data sources (all collected data) was used to analyse the data in order to determine the teaching and learning challenges of these novice teachers as well as how the identified needs were addressed. The data was organised into two themes, classroom and professional efficacy, sub-categories of teacher efficacy which refer to teachers’ own set of beliefs about their capability to successfully perform tasks related to teaching. To determine the views of the teachers about the effectiveness of the blended intervention workshops, patterns from the interviews were sought and categorised into themes. Triangulation of data sources was utilised to strengthen the reliability and validity of the emerging findings by drawing mainly on the written field notes as well as lesson observations collected before and after the intervention. To determine ways in which the teaching practice of these three novice teachers changed, triangulation of frameworks was used to categorise and analyse all the lesson observations. The frameworks used were the knowledge building approach from the pedagogical links making (PLM) framework and semantic codes from the legitimation code theory (LCT). Their lesson observations before the intervention were compared with those conducted after the intervention to note changes, or lack thereof, in the teaching practice of these teachers. Using the described analysis process, this study found that the blended professional development intervention failed to shape the teaching practice of these teachers. This failure was primarily the result of poor design of the blended professional development intervention. For example, insufficient time was allocated to some topics that were identified as challenging by the teachers. Page | XXII Additionally, those topics that the majority of the teachers found challenging and needed professional development on were not addressed in the intervention workshops. Furthermore, there was poor attendance in online workshops perpetuated by the lack of active engagement as well as lack of sufficient digital tools, particularly internet data to access the workshops. Moreover, there was lack of individual support in online workshops, which has a potential to promote opportunities of assistance tailor made to the needs of the teachers through coaching and/or mentoring. Although the intervention did not succeed in shaping the teaching practices of these novice Physical Sciences teachers, it was able to assist them in improving the performance of their learners. This success was because of the explicit focus on this aspect, whereby the strategies to prepare learners to pass the examination were shared with the teachers per topic. Due to improved learner performance, this study noted a newfound confidence in these teachers, particularly Messrs Jones and Brown, resulting in an improvement in their classroom and professional efficacy. As such, this study recommends that professional development initiatives should consider learner performance as a separate entity that requires explicit focus instead of treating it as a byproduct of improved teaching practice. Furthermore, blended professional development interventions must be carefully designed to shape teaching practice by focusing on developing teachers’ subject content knowledge and pedagogical content knowledge. It must be informed by the needs and goals of all education stakeholders, be of long duration - not less than twenty hours of contact time, encourage active engagement, provide individual support, make provisions for required digital tools, promote active collaboration and it must be sustainable. However, Mr Smith did not see any improvement in the performance of his learners. This study attributed this to the attitude Mr Smith has about learners who can take Physical Sciences, thereby affecting his teaching practice. Furthermore, he is not qualified to teach Physical Sciences and showed lack of competence in teaching the Chemistry component of Physical Sciences compared to the other teachers. Therefore, great care should be taken in professional development initiatives to ease such attitudes and provide the required support to all novice teachers with distinct backgrounds.
Development of an instrument to measure the quality of care after the withdrawal of life-sustaining treatment in the adult intensive care unit
(University of the Witwatersrand, Johannesburg, 2023-09) Korsah, Emmanuel Kwame; Schmollgruber, Shelley
Background: The majority of deaths in the intensive care unit occur after the withdrawal of life-sustaining treatment. Most patients often die within 24 hours after treatment has been withdrawn. The short time interval between treatment withdrawal and death has highlighted the urgent need to prioritize the quality of care provided for patients and their families during this period. In South Africa, the quality of care provided for patients after treatment withdrawal has been plagued with cultural differences, challenges, and ethical dilemmas. Currently, no instrument exists to measure the quality of care provided for patients at the end of life and their families after treatment is withdrawn in the adult ICU. Existing measuring instruments have been developed for western countries with no consideration for the South African context. Hence, using these measuring instruments, especially in a country where non-western cultures exist, may be inappropriate, unrealistic, and liable to fail, necessitating revision. Purpose: To develop an instrument to measure the quality of care provided for patients after the withdrawal of life-sustaining treatment and their family members in the adult intensive care unit. Methodology: An exploratory sequential mixed-methods research design was used. The study was conducted in two phases, namely: domain identification and item generation; and instrument development and validation. In Phase 1, a summary of findings from a scoping review of the literature and qualitative interviews with nurses, doctors, and family members were used to generate relevant content domains and items. Relevant items generated were synthesised and reduced to develop the first version of the measuring instrument in Phase 2. The instrument underwent further expert panel review for relevance and clarity. A content validity index and modified Kappa statistic were performed. Comments and feedback from the panel of nine experts were also used to assess the face validity of the instrument. Results: The instrument development and validation process yielded a final instrument that consisted of 64 items across 7 domains. From an initial set of 143 items, the content validity process found seven domains and 64 items. These included patient- and family-centered decision making (9 items), communication among the ICU team and with patients and families (12 items), continuity of care (3 items), emotional and practical support for patients and families (12 items), symptom management and comfort (7 items), spiritual care (5 items), and modifying the ICU environment (12 items). A study of content validity revealed that this instrument recorded an appropriate level of content validity. The overall content validity index of the instrument was high (S-CVI/Ave = 0.97) when using the average approach and moderate (S-CVI/UA = 0.77) when using the universal agreement approach. The moderate value of the S-CVI/UA can be advocated with respect to the high number of content experts that make consensus difficult. The instrument items also obtained excellent kappa values that ranged from 0.89 to 1.00. Conclusion: The researcher developed and validated the content of an instrument to measure the quality of care provided for patients and their families after the withdrawal of life-sustaining treatments in the adult ICU. This instrument will support the provision of care for patients and their families following treatment withdrawal and the training and education of healthcare providers in end-of-life care. It will also aid future research in the care of critically ill and dying patients in the ICU. Future research should conduct more assessments and pilot test the instrument.
Exploring students experiences of receiving e-formative feedback during emergency remote learning: A case study of first-year students at a teacher education university in South Africa
(University of the Witwatersrand, Johannesburg, 2024) Simelane, Raudina Madina; Pillay, Preya
The COVID-19 pandemic necessitated an abrupt transition to Emergency Remote Teaching and Learning (ERT&L) across the higher education landscape globally, including teacher education programs in South Africa. This seismic shift profoundly disrupted conventional assessment approaches dependent on face-to-face teaching and continuous formative assessments. Consequently, instructors were compelled to reconceptualise formative assessment for the realities of remote learning, adopting digital tools to administer e-assessments and provide e-formative feedback. Concurrently, first- year student teachers faced monumental challenges accessing and productively responding to digitally-mediated formative feedback amidst the isolating remote context lacking traditional supports. Against this backdrop, this qualitative case study explored the lived experiences of thirty- six first-year Bachelor of Education students receiving e-formative feedback through a university’s Canvas Learning Management System during ERT&L conditions in South Africa. Framed by an interpretive paradigm combining Social Constructivist, Feedback Intervention, and Feedback Design theoretical tenets, the study aimed to explore how students perceived and engaged with e-formative feedback to facilitate their self- regulated remote learning. Through Thematic Analysis of semi-structured interviews and focus group discussions, findings unveiled diverse student realities shaped by multifaceted technological, cognitive, and motivational barriers. Prominent obstacles included lack of digital access, connectivity issues, deficient computer literacy skills, and unfamiliar vocabulary – factors impeding feedback reception. Moreover, untimely and unspecific feedback further undermined its value, with many students prioritising marks over substantive comments. Ultimately, suboptimal design coupled with insufficient feedback literacy and self-regulation capacities among this vulnerable population severely constrained productive feedback engagement and autonomous learning progress during the emergency transition. This study’s findings highlight the need for reconceptualised e-formative feedback approaches that holistically account for technological equity gaps, targeted skills development, and psychosocial support mechanisms to foster meaningful feedback utilisation during disruptions. Crucially, it calls for elevating student voices to better understand their contextualised needs, informing responsive interventions. Emergent insights illuminate opportunities to enhance digital feedback literacy, diversify feedback modes, accelerate feedback turnaround, and nurture conducive ecosystems where first- year students thrive as empowered, self-regulating learners even amid crises. Such learner-centric innovations have lasting relevance for optimising equitable, sustainable assessment design across evolving educational futures.
Histo-morphological Perturbations in the Testes of Diabetic Sprague Dawley Rat Following Atripla® And Alcohol Co-administration
(University of the Witwatersrand, Johannesburg, 2023-08) Owembabazi, Elna; Nkomozepi, Pilani; Mbajiorgu, Ejikeme Felix
A decline in male fertility is increasingly becoming a major concern in this millennium. However, the associated effects of diabetes, alcohol abuse, and cART use and their interaction which are clinically important in male reproductive health have not received proper attention. Each of these conditions (diabetes, alcohol abuse, and cART use) has been shown to negatively impact the male reproductive system. Moreover, diabetes, alcohol abuse, and cART are intricately connected and thus can and occur simultaneously in an individual, a scenario that might provoke severe reproductive dysfunctions. Therefore, this study investigated the impact of diabetes, alcohol abuse, cART use, and their combinations on testicular histomorphometry, reproductive hormone profile, oxidative and inflammatory markers, germ cell proliferation and apoptosis, and androgen receptor expression. A total of forty-eight HIV naive rats (48) were divided into two main groups, non-diabetic and diabetic groups, which were further subdivided into four subgroups consisting of six rats each. The non-diabetic groups (1-4); Group 1; Control, Group 2: Alcohol treated (A), Group 3: combination antiretroviral therapy treated (cART), and Group 4: alcohol plus cART treated (A+cART). The diabetic groups (5-8); Group 5: diabetic only (DM), Group 6: diabetic treated with alcohol (DM+A), Group 7: diabetic treated with cART (DM+cART), and Group 8: diabetic treated with both alcohol and cART (DM+A+cART). The rats were fed normal rat chow and terminated after 90 days of treatment. Blood was drawn through a cardiac puncture into plain vacutainers, thereafter, animals were perfused with 0.1M phosphate buffer, and the testes harvested, weighed, and then fixed in 10% neutral buffered formalin for histology and immunohistochemistry analysis. During the experimental period, hyperglycemia, low glucose tolerance, and polydipsia were observed in the diabetic groups (5-8) only. Though, a general decrease in testis weight, volume, and size was found in all treated groups compared to the control group, a significant (p˂0.05) decrease was detected in the DM+A group only. With exception of the DM+A+cART group, the epithelial area fraction, epithelial height, and tubule area and diameter reduced significantly in all treated groups. The luminal area fraction and luminal diameter which significantly reduced in cART, DM, and DM+cART groups, were increased in A+cART. Further, connective tissue and interstitial area fractions increased significantly in all treated groups. The spermatogonia increased significantly in A, cART, DM, and DM+A+cART groups relative to control group, but reduced significantly in DM+A. However, spermatocytes, round spermatids, and elongated spermatids decreased significantly in all treated groups, with exception of spermatocytes of the alcohol group. All treated groups showed a decrease in the number of Sertoli cells relative to the control but a significant decrease was only found in the DM+A group, but all treated groups had significantly decreased Leydig cell diameter and volume. Johnsen’s testicular score was significantly reduced in A, A+cART, DM, and DM+A treated groups. Additionally, varying severity of seminiferous tubules (ST) lesions such as shrinkage of ST, lifting of epithelium, widened intercellular space, karyolysis, epithelial sloughing, ST atrophy, multinucleated giant cells, and germinal epithelium derangement were observed in the treated animal groups. Further, the thickness ST basement membrane increased significantly in cART, DM, and DM+cART groups but testis capsule thickness increased significantly in A+cART, DM+A, and DM+A+cART groups. The testicular interstitial connective tissue fibers viz. collagen, reticulin, and elastin reduced significantly in all treated groups, except for the reticulin which was non-significantly decreased in the alcohol (A) group. Furthermore, luteinizing hormone was significantly elevated in A and A+cART groups but significantly reduced in the DM+A+cART group. However, follicle-stimulating hormone increased significantly in all treated groups, with exception of DM+cART group. Testosterone levels were significantly reduced in DM, DM+A, and DM+A+cART groups, but no significant difference (p>0.05) was found in the inhibin B level in all treated groups compared to the control. In addition, the intensity and number of Sertoli and Leydig cells expressing androgen receptor were significantly reduced in all treated groups, except for the number of Sertoli cells expressing androgen receptor in the alcohol group. Expression of inflammatory markers (IL-1β, TNF-α, and IL-6) was upregulated in all treated groups, with exception of IL-1β of the A+cART group and TNF-α of cART and A+cART groups. The markers for oxidative stress (iNOS, MDA, and 8-OHDG) and apoptosis (caspase 3) were upregulated in all treated groups, with exception of MDA in the alcohol group. Though, the number of germ cells expressing proliferation marker Ki-67 was significantly reduced in all treated groups, the staining intensity was significantly increased compared to the control group. The results show that diabetes, alcohol abuse, cART, and their combinations have deleterious effects on the testicular histoarchitecture and function, which are suggested to result from the upregulation of oxidants and cytokines and androgen receptor depletion. The results further suggest that the interaction arising from a co-presence of cART and alcohol in diabetic condition could mildly diminish their independent effects due to their common cytochrome P450 metabolic pathway. This study yielded invaluable data on the contribution of cART alcohol-diabetes interaction on the male reproductive functioning/dysfunction and hopefully will help clinicians in managing reproductive challenges in patients of this category.
Inclusive education and the plight of children without legal documentation: A case study of Cosmo Oasis in Johannesburg, South Africa
(University of the Witwatersrand, Johannesburg, 2024) Matanhire, Vimbayi; Carrim, Nazir
Children without documentation are excluded from formal school due to contestations and contradictions between the South African Constitution and the Admission Policy for Ordinary Schools and the practices of the Department of Home Affairs alongside legislative gaps and inconsistencies in South African schools regarding the admission of children without legal identification documents. This study investigated the plight of children without legal documents in relation to inclusive education in South Africa using a case study of a non- governmental organisation named Cosmo Oasis. I argue that a human rights approach to inclusive education within the social model paradigm is essential for this study because education is in itself a human right. I further develop a framework of inclusive education for undocumented children and outline the intricacies surrounding the origins and debates around the universality and enjoyment of human rights specifically by children without documentation. This study was a qualitative study that used mixed methods and it had the characteristics of a case study. Semi-structured audio-recorded interviews and questionnaires with open and closed questions were used as data collection tools. Data was analysed using qualitative data analysis methods by organising and sorting data into major themes and presented in the form of figures, tables, excerpts and descriptions. The findings of the study showed that, the South African education system was not inclusive to children without legal documents. These children are not integrated into the mainstream leading to varied socio-economic and political implications on the children without documents, their parents and on the South African education system. Contradictions between policies, the legal aspect, the Home Affairs Department, revealed the contestation between citizenship rights and problems with the social contract which continues to create an impasse between the realisation of rights by non-citizens and the rigidness of the social contract.
Internships & intentions: A grounded theory study of a South African government graduate internship programme
(University of the Witwatersrand, Johannesburg, 2024) Hendricks, Sumaya; Hewlett, Lynn; Wedekind, Volker
The researcher used a grounded theory approach to understand the factors which affected intern learning on a graduate internship programme run by the South African government, with a focus on one national government department. In particular, the focus was on understanding how factors worked to create a disjuncture between the intended and experienced curriculum. To conduct this research, interviews were conducted with interns who completed their internship in the 2018-2021 period; HR officials; and mentors – all of whom were based in the department of focus. This was complemented with document analysis and intern demographic data. While the interest in this subject matter was from a learning perspective, this programme is also a labour market intervention to help alter the bias towards these young, black and unemployed graduates who are the target audience of this programme. In this study, the central phenomenon that emerged is that of Curricular fission which is a metaphor to describe a situation in which various factors worked to create a rupture between what interns were intended to learn compared to what they actually learned. In short, the metaphorical large atom which caused the fission were institutional, individual and task related factors with these factors preventing interns from moving from legitimate peripheral participants to full participants. Institutional factors operated at the level of the department, individual factors concerned the individual - whether that be the intern themselves; the government officials that interns reported to; or other people interns interacted with - while task related factors were related to the tasks allocated to interns, which had a direct bearing on intern learning. While the interns had control over some of the factors, many were ‘beyond’ their control which reinforces the view of learning as being shaped, hindered or aided by factors beyond the learners themselves. With a situation of curricular fission characterising the overall intern learning experience, the programme could be considered a form of ‘warehousing’ which in a South African context carries a transformation component arising from the ‘special’ burden that workplaces have in addressing the bias towards black graduates.
Teachers' Discourse, Language, Genetics, Life Sciences, South Africa, classrooms
(University of the Witwatersrand, Johannesburg, 2024) Mupfawa, Shungu
South Africa has consistently ranked close to the bottom in international studies on the quality of mathematics and science education. This poor performance portrays a negative picture of the quality of teaching and learning science and mathematics in the country. Local reports such as the South African National Diagnostic Report on grade 12 performance attest to this as it shows that the quality of passes in life sciences at the matric level is low. As a result, fewer matriculants enrol for life sciences-related careers at higher institutions of learning. The overall quality of passes in life sciences could be aggravated by the poor performance of learners in genetics-related questions which make a substantial contribution to scores in the Life Sciences examination. Literature on the teaching and learning of genetics also points to difficulty with the teaching and learning of this topic, including the use of language by the teachers. This thesis reports on a case study in which I investigated the classroom Discourse of four life sciences teachers while teaching basic genetics to grade 12 learners. The study aimed to characterise the teachers’ Discourse during the teaching of basic genetics. In this study, my conception of Discourse was influenced by Gee’s Theory of Discourse which makes a distinction between Discourse with an upper-case ‘D’ denoting language and other factors associated with it and discourse with a lower-case ‘d’ as referring to language. Therefore, in this study, the teachers’ Discourse ‘D’ was conceptualised in terms of language ‘d’ (the language of science) and context which entailed Discourse strategies, interaction patterns, teacher Discourse moves, and multimodal representations. This study drew on literature and research from the fields of Discourse analysis, language, teacher talk, science teaching, and classroom Discourse to develop a complex picture of the classroom. A case study was conducted in three high schools in Johannesburg, South Africa. Data was collected from four teachers each of whom was observed three times, and video recorded while teaching basic genetics concepts to grade 12 learners. A follow-up interview was conducted with each teacher. These post-observation interviews together with field notes were added for data triangulation purposes. The interviews helped me to access teachers’ rationale for taking certain actions during the observed lessons. Moreover, the interviews enhanced the trustworthiness of my analysis. The lesson observation transcripts were analysed using Lemke’s Thematic Analysis merged with Mortimer and Scott’s Communicative Approaches and Discourse patterns. This study unveiled two major types of Discourse of teachers who followed an examination based approach and teachers whose Discourse followed a conceptual approach. This led to the development of a Discourse Teaching Strategy Model which portrays teachers as being either conceptually or assessment focused. My Discourse Teaching Strategy Model shows that amongst other characteristics, conceptually focused teachers used higher-order questions to build conceptual understanding and logical exposition for consolidation. Further, the model shows that logical exposition was sometimes replaced by selective summary where the teachers justified the curriculum. Teachers adopting a conceptual focused strategy used controlling pacing and marking importance as pedagogical measures and admonition for maintaining discipline. This study contributes to the effective teaching of genetics by offering the Discourse Teaching Strategy Model as a model to guide thinking about the planning and development of science teaching as well as a tool for reflection upon one’s teaching strategies. Thus, this model can be used to expand self-development or in-service development especially if one is to teach for ii conceptual understanding. Researchers can use the model as an analytical tool for identifying a particular teacher’s Discourse practices.

4. Electronic Theses and Dissertations (ETDs) - Faculties submissions

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