OpenUCT is the open access institutional repository of the University of Cape Town (UCT). It preserves and makes UCT scholarly outputs digitally and freely available, including theses and dissertations, journal articles, book chapters, technical and research reports, as well as open educational resources.

 

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Open Access
Retrospective analysis of the utilisation of DNA analyses in the identification of human remains at Salt River Mortuary (Cape Town, South Africa)
(2024) Kambowo, Sophy Celine; Heathfield, Laura Jane; Reid, Kate
Post-mortem human identification is crucial for medico-legal investigations and for social justice. Unfortunately, many people remain unidentified, particularly in developing countries. The use of forensic DNA profiling is a reliable method for human identification and was legislated in South Africa in January 2015. However, the use and success of DNA as an identification tool at Salt River Mortuary (SRM) in South Africa are unknown. Medico-legal case files were reviewed from all 3696 cases admitted in 2015, to evaluate the use of DNA in identifying human remains at SRM immediately after the implementation of the ‘DNA Act'. While 213 (5.76 %) cases were admitted in 2015 without an alleged identity, 221 individuals had no confirmed identity following post-mortem and identification attempts. DNA samples (for identification and/or investigative purposes) were taken in a total of 490 cases, yet concerningly, these samples represented many people with a confirmed identity, and not all individuals without an (alleged) identity. Of the 221 unidentified human remains, only 62 (28 %) were afforded DNA analysis, suggesting an underutilisation of DNA analysis requests. This observation highlights a potential missed opportunity to leverage DNA technology more comprehensively in cases where conventional identification methods prove insufficient. Further, DNA results were only obtained for 64 cases (13.06 %) with results from 426 cases still outstanding seven years later. Where reports were available, identification via familial matching was successful in 95.31 % of cases (n = 61/64), leading to a success rate of 12.45 % (n = 61/490) for DNA as an identification tool. This poor success rate in 2015 could be attributed to several factors including: inadequate sampling post-mortem possibly due to unclear guidelines about which state authority was responsible for sampling, the low chances of a match on the National Forensic DNA Database due to its infancy (and thus containing few reference DNA profiles), next-of-kin not providing reference samples due to lack of awareness or fear of authorities, or inadequate infrastructure or access to resources. This study highlights the need for intentional and consistent sampling of unidentified human remains and calls for larger efforts to encourage next-of-kin to provide reference samples to increase the chances of identification.
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Open Access
Assessing the chronic barriers to justice faced by domestic violence survivors in the Western Cape
(2024) Grotzinger, Lior; Moult, Kelley
This dissertation examines the chronic barriers to justice faced by victims of domestic violence survivors in the Western Cape. It delves into the factors causing domestic violence survivors to disengage from the criminal justice system and investigates why many victims do not follow through with finalizing their protection orders. The high attrition rate in domestic violence cases in South Africa is a significant issue because it hinders the delivery of justice for victims and perpetuates cycles of abuse. When victims disengage from the criminal justice system or do not follow through with finalizing protection orders, they may remain in dangerous situations without adequate protection. This lack of closure and resolution can lead to continued incidents of abuse, putting victims' safety and well-being at risk. Additionally, the high attrition rate can erode trust in the justice system among domestic violence survivors, further discouraging them from seeking help in the future. Addressing this issue is crucial for providing effective support and protection to domestic violence survivors and holding perpetrators accountable for their actions. The study involved a thematic analysis of qualitative case notes recorded in 154 preselected case files, with data entry completed using Survey Monkey. The case files were collected by MOSAIC staff between January 2022 and December 2022. The survey encompassed 16 questions, targeting various aspects such as court location, follow-up reachability by MOSAIC, client engagement with SAPS for case filing, court appearance on designated dates, type of abuse experienced by clients, and reasons behind incomplete protection order processes. The data indicates that survivors refrained from reporting domestic violence to SAPS due to unfair and arbitrary treatment by SAPS officials. Furthermore, survivors often decide not to finalize protection orders when abuse cases and the respondent's behavior improves. MOSAIC workers report that SAPS officials advised survivors to obtain a restraining order first because they take back their abusers which results in wasted time and resources. Additionally, the data also highlights that some clients are unaware of the processes that need to be followed when dealing with protection order violations. Clients are also unaware of their option to reapply for an interim protection order if they have withdrawn their application or missed the return date, leading to a miscarriage of justice. The MOSAIC Court Case Monitoring Officer contacts clients seeking assistance to ensure they have received the necessary services. However, clients are at varying stages in the protection 9 order process, and many do not return after receiving an interim or final protection order. This causes challenges in tracking clients through the justice system and assessing whether they have received the required support. A reduction in the high attrition rate in domestic violence cases can be achieved through SAPS officials demonstrating more compassion and understanding, as mandated by the Domestic Violence Act 116 of 1998 (DVA) and the Domestic Violence Amendment Act 14 of 2021 (DVAA). Additionally, an improved understanding of the interim and final protection order process by applicants is crucial. Keywords: domestic violence, interim protection order, final protection order, chronic barriers
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Open Access
How is work-integrated learning adapting to the future of work and employability? A phenomenograhic study of graduate mathematicians internship experiences across selected African
(2024) Heerden, Mark; Hall, Martin
The future of work and employability is evolving at an accelerating pace, impacted by the changes brought about by the fourth industrial revolution and the increasingly digital economy. This research study explored work-integrated learning through a sample of African graduate mathematicians' collective internship experiences. The research methodology was based in phenomenography, which seeks to understand the collective outcomes experienced by the participants from their workspace internships. Twenty participants were purposively selected to give a broad range of experiences and maximise the likelihood of variation. All were mathematics graduates or postgraduates who sought employment in industry. They represented eight African countries, and 55% were female. Although almost all responded that their internships were positive work-integrated learning experiences, they also highlighted their challenges in meeting the demands of the workspace internships. Six further distinct collective outcomes, or conceptions, were experienced centered around managing their expectations, company readiness, structured supervision, workplace training, team inclusion and independent working. The study also found that the learning experiences in the African workplace were largely comparable with those experienced in more industrialised countries, as reflected in the literature. However, a key recommendation arising from this study is the need for greater structure in the African internships, termed ‘structured hospitable learning spaces', better connecting the learning environment for interns and employers. The participants collectively believed this greater structure was necessary to improve their internship experiences, both aimed at themselves in that they should have better prepared before their internships, and then at the internship companies, where there should have been more planning for their arrivals. This study concludes by asserting the growing importance of work-integrated learning in the future of work and, in particular, data analytical roles in the accelerating digital economies of African countries. It also recognises the impact that generative artificial intelligence solutions will have on learning in the decades to come. Keywords: work-integrated learning, experientiall learning, African internships, future work, phenomenography, digital economies, workspaces
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Open Access
Fractional-N PLL-Based Waveform Synthesis for FMCW SAR
(2024) Gwasira, Thomas; Paine, Stephen
Achieving high-quality transmitted and local oscillator signals is a core objective in the design and implementation of high-resolution radar imaging systems, as the reconstructed images depict the interaction of the signals with elements in the scene. This dissertation concerns optimisation of the imaging capabilities of a frequency modulated continuous wave (FMCW) synthetic aperture radar (SAR) system, named the miloSAR, by improving the frequency synthesis aspects of the system. This is done by considering the phase-locked loop (PLL) synthesiser employed and waveforms, thereof, in terms of dynamic response characteristics and frequency response characteristics. The dynamic response component entails studying parameters which include the modulation period, modulation bandwidth, sweep rate, pulse repetition frequency (PRF) and slew rate among others and their influence on SAR image quality of the system in question. It was discovered that to better the performance of the system as it relates to these parameters, the radar system and the synthesiser had to be modelled and characterised in order to realise more optimal waveforms such as the sawtooth waveform which previously was not possible owing to limited information on the PLL's dynamics. Furthermore, the signal acquisition system was redesigned to increase the data rate of the system from 11 MB/s to 43.231 MB/s, thus, allowing support for higher PRFs and sample rates. Frequency response characteristics involve stability of both the synthesiser and the generated waveforms. The main issues related to this were identified to be ramp non-linearity, spurs and phase noise. Phase noise was the primary concern for this work since sufficient ramp linearity was achieved by the synthesiser and spurs have been addressed in another author's work on the miloSAR. Two independent synthesisers were, in fact, used to realise the heterodyne architecture required for the miloSAR and they were observed to exhibit significant phase instability. Due to the range correlation filtering effect achieved by using the same clock as the reference inputs of the PLLs and the ADC clock, phase noise caused by strong targets was considered to be less of a concern. However, the phase noise skirt of antenna leakage was identified as a major cause of performance degradation since the leakage is high in power and its phase noise skirt, in regions where range correlation filtering does not occur, swamps weaker radar returns. This becomes an even bigger problem when the PLL bandwidth is increased to improve the PLL's dynamics. The insights from both perspectives of the waveform synthesis problem were combined to give an instructive conclusion on how waveform synthesis must be carried out for the miloSAR and recommendations for a more performant system were proposed.
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Open Access
Determining the role of differential expression of candidate icroRNAs in cardiometabolic diseases among South African adults living with HIV
(2024) Govender, Leegan; Dandara, Collet; kengne Andre
Background: MicroRNAs (miRNAs) are potential prognostic/diagnostic markers that have been investigated for screening of cardiometabolic disease (CMD) risk in general populations. However, little is known about their value in people living with human immunodeficiency virus (PLWH), who have an increased susceptibility to CMDs. PLWH have an increased susceptibility to CMDs because of chronic inflammation caused by a persistent immune response, metabolic complications from antiretroviral therapies, and traditional risk factors. In this study the association of differential expression of candidate miRNAs, miR-126-3p, -223-3p, and -320a with CMDs was investigated among PLWH. Methods: Using a cross-sectional study design ≥18-year-old PLWH were recruited from 17 random HIV clinics in the Western Cape, South Africa between 2014-2015. Standard international definitions were used to diagnose CMDs. Whole blood miRNAs were isolated, and expression quantified by reverse transcription quantitative polymerase chain reaction. MiRNA expression was compared between participants with a CMD and without for each investigated outcome, using Wilcoxon rank sum/Kruskal Wallis tests. Robust correlations, robust linear regressions and logistic regressions assessed miRNAs relationships with cardiometabolic risk profiles. A p-value <0.05 was considered statistically significant. Results: Among 675 participants (81% women), prevalence of CMDs/traits was: elevated highsensitivity C-reactive protein (67.4%), raised waist circumference (WC) (63.3%), obesity (34.1%), insulin resistance (IR) (9.9%), and diabetes mellitus (8.6%). Target miRNAs were not significantly differentially expressed based on individual CMD statuses. However, target miRNAs were significantly correlated with glucose homeostasis variables [fasting glucose (r≤0.129, p≤0.046); fasting insulin (r≤0.115, p≤0.015); 2-hour insulin (r≤0.097, p≤0.029); and homeostatic model assessment of insulin resistance (HOMA-IR) (r≤0.144, p≤0.002)], and miR126-3p and -223-3p were significantly correlated with alanine transaminase (r≤0.128, p≤0.022). In linear regression models after adjusted for age and gender, miR-126-3p had a borderline association with HOMA-IR (β≤0.018, p≤0.081), while miR-223-3p was borderline associated with glucose when adjusted for age, gender, and WC (β=0.001, p=0.066). There were no significant associations in logistic regression models. Conclusion: The miRNAs tested in this study appear not to be important markers for CMDs in PLWH. A genome-wide approach is recommended to uncover other miRNAs with potential as biomarkers of CMDs in PLWH.