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
Post caesarean section complications in women infected with COVID-19 disease
(2026) Maboko, Rendani; Matjila, Mushi; Maswime , Salome
Background: The COVID-19 pandemic had a multifaceted impact on maternal health and pregnancy outcomes. This study aimed to determine the impact of the COVID-19 on caesarean section outcomes in pregnant women with COVID-19 infection in South Africa.
Objective: To evaluate post-operative outcomes in women who were diagnosed with COVID-19 infection, who underwent a caesarean section delivery while hospitalized in South Africa, during the pandemic.
Methods: A secondary analysis was conducted on data from a multicentre national database by the International Network of Obstetric Survey Systems (INOSS). The dataset included hospitalized pregnant women diagnosed with the COVID-19 disease between 14 April 2020 and 9 December 2021 in South Africa. Statistical analyses were performed to determine the association between mode of delivery, postoperative complications and mortality.
Results: Among 456 women who delivered by caesarean section. Complications were seen in 74 of 456 (16.2%) women. There was a statistically significant association between caesarean delivery and post-operative complications (p = 0.04). Mortality in COVID-19 positive women undergoing caesarean was 6.1%. Elective caesarean sections (9.02%) were associated with a notably higher rate of mortality compared to emergency procedures (2.5%). Notably 71.4% of maternal deaths amongst those who delivered by caesarean section were due to COVID-19 related respiratory complications.
Conclusion: Caesarean section in COVID-19 positive women was associated with increased postoperative complications, especially in the elective cases. Mortality in this cohort was mainly due to respiratory complications. These findings suggest the need for more refined clinical protocols and careful surgical decision-making during pandemics, especially in resource constrained settings.
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Open Access
An analysis of the Fama and French Five-Factor models significance pre- and post-COVID-19 on 30 U.S. industry portfolios
(2026) Chaibva, Tendayi; Chun-Sung, Huang
This study examines the Fama and French Five-Factor (FF5) model's significance, explanatory ability and model fit across 30 United States (U.S.) industry portfolios in the pre- and post-COVID-19 periods. The research investigates whether the pandemic an exogenous global financial shock altered the model's explanatory power and the stability of its factor loadings. Grounded in multifactor asset pricing theory, the study aims to determine whether the relationships between expected returns and the five key risk factors market (MKT), size (SMB), value (HML), profitability (RMW) and investment (CMA) remained consistent or experienced structural change following the pandemic. Using quantitative regression analysis, the research employs Ordinary Least Squares (OLS) techniques to test the FF5 model on both daily and monthly data obtained from the Kenneth R. French Data Library. The analysis compares two distinct periods pre-COVID-19 (January 2017–December 2019) and post-COVID-19 (January 2021–December 2023) while excluding 2020 due to extraordinary market volatility. The model's performance is evaluated based on changes in factor coefficients, p-values, adjusted R² and F-statistics to assess variations in explanatory power and statistical significance. The findings indicate that the Fama and French Five-Factor model retained its overall explanatory power across both periods, with the adjusted R² increasing post-pandemic. The market (MKT) and value (HML) factors remained consistently significant across most industries, while the profitability (RMW) and investment (CMA) factors exhibited improved stability in the post-COVID-19 period, particularly in capital-intensive sectors. The OLS F-statistics also revealed a general rise in model significance, underscoring stronger factor driven relationships after the pandemic. Overall, the results support the null hypothesis (H₀) that there is no significant difference in the FF5 model's explanatory power between the pre- and post-COVID-19 periods. The study concludes that the FF5 model remains a robust and reliable framework for explaining industry-level asset returns, even amid structural economic disruptions. These findings reaffirm the model's theoretical validity and empirical relevance in evolving financial environments, providing valuable insights for both academic research and investment strategy formulation.
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Open Access
Memory and the afterlives of images: Jacqueline Quin and Leon Meyer, Maseru, 20 December 1985
(2026) Duggan, Jo-Anne; Field, Sean
This thesis takes as its starting point three photographic images of the bodies of Jackie Quin and Leon Meyer laid out in a mortuary in Maseru, following their assassination in a cross border raid into Lesotho by South African security force operatives in December 1985. In their afterlives the images, first circulated in news media, have inspired a novel and a song, been used to illustrate a poem and an educational text and repurposed in publications, documentary films, exhibitions, and on social media. Drawing on oral history dialogues with photographers, journalists, writers, artists activists, archivists and exhibition curators, and on literature on the intersection of visuality, psychology, narrative and memory studies, the thesis aims to track the way the images have been remembered, misremembered or forgotten over a period of almost four decades. Interlocutors were asked to focus on, and speak about, the images as they came into view in memory, rather than on a printed surface or a digital screen. This highlighted the complex entanglement of visuality, affect, narration and memory. An analysis of the dialogues suggest that the images live on in memory as objects of affect rather than for their indexical status. Interlocutors remembered their encounters with the images in precise detail, but their memories of the event with which they were associated were vague. Speaking about remembered images blurred the boundaries between past and present, the self and other, affect and cognition, raising into consciousness deep-seated vulnerabilities, anxieties, grief, and regrets that might otherwise have remained unsaid. The dialogues also highlighted the stark differences between the images made by photographers and those encountered in the atemporal and subjective domain of memory, constantly susceptible to embellishment, erasure or reconfiguration. Listening and watching as interlocutors recalled the images, and described them in language and gestures, offered insights into the way in which the conscious and unconscious collude to shape and frame images seen in the mind's eye. This thesis argues that oral history dialogues produce intangible traces of the images of Jackie and Leon, as well as other remembered photographs and mental images. These vestiges constitute a complex archive that loops between past/present, personal/political, and individual/collective memory and brings into consciousness the almost unthinkable, unseeable, unsayable and unrepresentable.
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Open Access
Matterightblooming Phenomenon: using George Saunders' Lincoln in the Bardo to theorise the literariness of Western Death
(2026) Devy, Shannon; Anderson, Peter; Busuku, Sindiswa
The fact that death is unknowable is, as Richard A. Cohen points out, quite simply “common sense”. But death – that is, what it is like to really die and what happens to us after we are dead – is a very special kind of unknown, one that is by its very nature unknowable, and one that puts tremendous pressure on our conceptual and symbolic systems, to interesting effects. Death's total withdrawal not only disrupts the order of representation and untethers the symbolic (for example, detaching the proper name from the body so it circulates without it, or robbing the word “loss” of its subject), but it also refuses the position of noema. As a result, as Critchley, Godly, Lacan and others have argued, death is un-experienceable, unobservable, unspeakable and even unthinkable. In order to apprehend death in our lives, we fill the void beyond the death-line with powerful literary material: metaphors, stories, myths, narratives, oral traditions, all of which “stand in” for death. This is a fundamental yet oddly under-theorised feature of death: we cannot apprehend death without deploying the literary, so death and the literary are inextricably tangled, always paired, and possibly one and the same. This dissertation aims to make an argument for the literariness of Western death, attempting to show that death's total withdrawal means it is only accessible to the living through creative, imaginative and, indeed, literary processes and materials. Building upon existing work by Critchley, Zupančič, Godly and others, it attempts to theorise both death as extra generative and the double-work of afterlife narratives. Drawing on the works of Blanchot, Derrida, and others, it surfaces and examines some of the deep entanglements between death, language and creativity, exploring the ways in which death is situated at the heart of the creative process itself and the connection between the corpse and the corpus, while expanding Blanchot's notion of the creative act as facsimile death by proposing ways in which this may be true. Lastly, it deploys George Saunders' extraordinary afterlife vision, Lincoln in the Bardo, to examine and theorise some of the ways Western death's literariness manifests in our day-to day handling of death, including applying Foucault's notion of the heterotopia to death for the first time, positioning euphemism and metaphor as “death's favourite devices”, and applying Blumenberg's concept of the absolute metaphor to death.
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Open Access
Thermofluid design and dynamic simulation of an sCO2 power cycle for a 50 MWe concentrated solar thermal tower plant in Southern Africa
(2026) Du Sart, Colin F; Bello-Ochende, Tunde; Laubscher, Ryno
Supercritical carbon dioxide (sCO2) power cycles have been identified as an attractive technology to reduce the cost, complexity and footprint, and to increase the thermal efficiency of thermal power plants. In this work, two promising sCO2 power cycles are investigated for use in a proposed dry-cooled 50 MWe concentrated solar power (CSP) plant in Southern Africa. These include the partial cooling with reheating (PCRH) cycle and the recompression with intercooling and reheating (RCICRH) cycle. Initially, a techno-economic design point study is performed to determine near optimal operating conditions and component requirements in which the recuperators are optimally sized, by volume, as printed circuit heat exchangers (PCHEs). This contrasts with other comparative studies where simplified models are used that do not consider the effect of actual recuperator geometry on heat transfer and pressure drop. The results suggest that the RCICRH cycle requires larger recuperators and turbomachinery, resulting in a marginally higher capital outlay for the power cycle, but offers superior thermal efficiencies, which suggests that a smaller solar field is required. However, the PCRH cycle requires a smaller solar receiver system and a smaller thermal energy storage (TES) system. Thereafter, conceptual designs for the cycle components (compressors, turbines, heaters and coolers) are developed. Additionally, auxiliary equipment (piping, valves, fans, TES tank and inventory tank) is sized and selected. Given the limited data available on sCO2 component modelling, unique sizing methodologies that employ fundamental one-dimensional (1D) thermofluid network modelling approaches are developed and verified. Compared to models used by others, which often contain significant simplifying assumptions, the models used in this work are more suited for off-design and transient power cycle studies, and for costing. Furthermore, by developing component designs for both cycles, the similarities and differences of the PCRH and RCICRH cycles are further clarified. A dynamic model of the RCICRH cycle is then developed. Using the model, a bypass and fan on-off control strategy for a multi-cell mechanical forced draft air-cooled heat exchanger (ACHE) system is proposed and demonstrated for the first time during changing ambient conditions. The model is also used to characterise the off-design performance of the cycle and the changing component boundary conditions for various methods of load control. Finally, the transient performance and operating requirements for the cycle are investigated. Accurate and stable load-following can be achieved using a combination of inventory and upper cycle bypass control. Furthermore, by using both upper cycle bypass control and compressor outlet throttling, the cycle can continue to operate during a load-rejection event. This is the first sCO2 study where all major cycle components are designed, fully integrated, and used to perform a comprehensive off-design and dynamic study for a cycle of this output capacity for a CSP application. While the selected boundary conditions and technological limitations considered in this study are unique to Southern Africa, many of the methods presented in this work may be used to develop conceptual designs for sCO2 power cycles of a similar scale.