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Item The Care-Climate Nexus - A Conceptual Framework(2025-01) Phalatse, Sonia; Taylor, Julia; Valodia, ImraanAs is widely acknowledged and evidenced, climate change threatens food security and sovereignty; water availability, accessibility and quality; health and livelihoods. Where women bear the primary responsibility of unpaid care work such as food provision, water collection, and care for the young, sick and elderly, climate change disproportionately disadvantages them. This applies to the work of care and, more broadly, to social reproduction. Climate change thus contributes to an ongoing crisis of care, exacerbating the injustices associated with women carrying a disproportionate share of unpaid care. As such, fostering a value for care could be a means through which social and environmental inequalities are equally addressed in an ecological transition. This paper expands on the conceptual linkages of a care-climate nexus, with the aim of supporting climate policy.Item Batch and semi-continuous fermentation with Parageobacillus thermoglucosidasius DSM 6285 for H2 production(BMC, 2025) de Maayer, Pieter; Ardila, Magda S.; Aliyu, Habibu; Neumann, AnkeBackground Parageobacillus thermoglucosidasius is a facultatively anaerobic thermophile that is able to produce hydrogen (H2) gas from the oxidation of carbon monoxide through the water–gas shift reaction when grown under anaerobic conditions. The water–gas shift (WGS) reaction is driven by a carbon monoxide dehydrogenase– hydrogenase enzyme complex. Previous experiments exploring hydrogenogenesis with P. thermoglucosidasius have relied on batch fermentations comprising defned media compositions and gas atmospheres. This study evaluated the efects of a semi-continuous feeding strategy on hydrogenogenesis. Results A batch and two semi-continuous fermentations, with feeding of the latter fresh media (with glucose) in either 24 h or 48 h intervals were undertaken and H2 production, carbon monoxide dehydrogenase (CODH) activity, and metabolite consumption/production were monitored throughout. Maximum H2 production rates (HPR) of 0.14 and 0.3 mmol min−1, were observed for the batch and the semi-continuous fermentations, respectively. Daily feeding attained stable H2 production for 7 days, while feeding every 48 h resulted in high variations in H2 production. CODH enzyme activity correlated with H2 production, with a maximum of 1651 U mL−1 on day 14 with the 48 h feeding strategy, while CODH activity remained relatively constant throughout the fermentation process with the 24 h feeding strategy. Conclusions The results emphasize the signifcance of a semi-continuous glucose-containing feed for attaining stable hydrogen production with P. thermoglucosidasius. The semi-continuous fermentations achieved a 46% higher HPR than the batch fermentation. The higher HPRs achieved with both semi-continuous fermentations imply that this approach could enhance the biohydrogen platform. However, optimizing the feeding interval is pivotal to ensuring stable hydrogen production.Item Making a mark: Wits School of Construction Economics and Management and Its Contribution to the Construction and Property Fields(University of the Witwatersrand, Johannesburg, 2024) Laryea, Samuel; Smit-Stachowski, Alexandra; Mphuti, BongiThis book is a historical account on the Wits School of Construction Economics and Management, its contributions and impact in society, which is very significant and leaves a positive impression of academic and industry development, despite historical hurdles. It looks at the past, present, and future of the School in the broader context of South African history and the overall development of the university. The process of writing this book has been both challenging and exciting with interesting discoveries about the academic disciplines and the growth trajectory of the School. It was challenging uncovering information from various sources within the university and external sources. It has also been an interesting process learning about the rich history and contributions of a key School within the university to the South African and global society. This book chronicles the careers of some graduates of the School who served in the highest leadership and management roles, and made an indelible mark in the construction industry locally and internationally. The School’s graduates have made substantial contributions to the growth and advancement of the South African construction and property sectors and their respective statutory councils including the South African Council for Quantity Surveying Profession (SACQSP), South African Council for Project and Construction Management Professions (SACPCMP) and the South African Council for the Property Valuers Profession (SACPVP). The School’s graduates have also played leading roles in major construction firms that have built some of the iconic buildings in South Africa and other parts of the world. In recent years, many of the School’s graduates are increasingly being recruited by firms in Europe, Middle East, Australia, and the US, indicating the quality of their education and their value to employers and the global construction industry. Through a meticulous search through the Wits university archives and available published material, a huge amount of history and contributions of the School could be produced in this book. As these sources spoke their minds, many of their quotes are produced verbatim - so we can appreciate their wisdom. When gaps emerged in the historical chronology, we turned to those who studied and taught at Wits in the various phases of our Faculty. The Alumni and past Academics took time from their busy schedules as many are still instrumental in building our country, to answer several questions and share their fondest memories and what they believe is the state of the industry currently. The original 15-page document has grown and developed, as has the School, into a fully-fledged manuscript of interviews, yet-unheard-of stories and a vibrant and vital document, to be read and shared widely. The story arc includes the factual history of the School of Construction and Economic Management from birth until now, and is peppered with amusing anecdotes and pictures. Students’ awards were mentioned, where the information was available. This also serves to remember the inspiring academics including Professors Harry Bell-John, Geoff Pearse, Doug Calderwood, Ronnie Schloss and the lecturers who led our current leaders in the fields of quantity surveying, construction management, building sciences and property development, onto the path they have carved, so they can make a mark. This story is filled with chutzpah, grit, determination, humour and a few mishaps, but proves without a doubt that the time spent by students at Wits and SCEM has resulted in lasting friendships, business savvy and in professionals in the built environment who are making their mark across the country, the continent and the world. This is their story and the story of the School of Construction and Economic Management.Item Price discrimination in merger review in South Africa: Implications of recent case precedent(Southern Centre for Inequality Studies (SCIS) University of the Witwatersrand, Johannesburg, 2025-02-12) Leuner, RahmaMergers have the potential to give firms access to more data from which to draw insights about consumers. This may help firms to better discern which consumers are price insensitive or captive, or exhibit behavioural biases, that they can exploit by charging them higher prices or nudging them towards higher priced options. Based on recent case precedent, we believe that the transfer or sharing of data or techniques in mergers involving price-discriminating firms may be sufficient for meeting the requirement of merger-specificity without there needing to be an increase in market power. Recent local case precedent also provides insight into when mergers impact on just a small group of consumers are likely to matter. It suggests that the competition authorities in the country should be more concerned where consumers are vulnerable and where access to the services/products is particularly important to this group.Item Budget 2025 Preview: Pressures and tensions along the austerity road to fiscal sustainability(Southern Centre for Inequality Studies, 2025-02) Sachs, Michael; Amra, Rashaad; Madonko, Thokozile; Willcox, OwenThis policy brief, ahead of the tabling of the 2025 Budget Review, considers the policy context and the fiscal and economic environment in which the Budget will be tabled. It considers the merits, limitations, and likely consequences of the government’s approach to budget policy over the medium term, as contained in the 2024 Medium-Term Budget Policy Statement (MTBPS), which redoubled efforts to consolidate public finances while attempting to promote capital spending. Since the MTBPS, several material expenditure pressures have emerged, some of which were flagged in the Public Economy Project’s (PEP) 2024 MTBPS analysis, and the economic outlook has been revised. Based on this, the Public Economy Project’s revised outlook for public finance finds that the government’s ambitious plan to stabilise debt over the medium term is unlikely to be realised.Item New modern and Pleistocene fossil micromammal assemblages from Swartkrans, South Africa: Paleobiodiversity, taphonomic, and environmental context(Elsevier, 2024-03) Steininger, Christine; Clarke, Ronald J.; Caruana, Matthew V.; Kuman, Kathleen; Pickering, Travis Rayne; Linchamps, Pierre; Stoetzel, Emmanuelle; Amberny, LaurieThe oldest deposit at the hominin-bearing cave of Swartkrans, South Africa, is the Lower Bank of Member 1, dated to ca. 2.2 million years ago. Excavations of this unit have produced a diverse and extensive mammalian fossil record, including Paranthropus robustus and early Homo fossils, along with numerous Oldowan stone tools. The present study focuses on the taxonomic analysis of the micromammalian fossil assemblage obtained from recent excavations of the Lower Bank, conducted between 2005 and 2010, as part of the Swartkrans Paleoanthropological Research Project. The taxonomic composition of this assemblage is dominated by Mystromys, a rodent indicative of grassland environments. Taphonomic analysis indicates an accumulation of prey by Tyto alba (Barn owl) or a related species. Environments inferred from this evidence reflect an open landscape primarily covered by grassland vegetation, but they also feature components of wooded areas, rocky outcrops, and the proximity of a river. The Swartkrans fossil assemblage is compared with Cooper's D (dated to ca. 1.4 Ma) and a modern coprocoenosis of Bubo africanus (spotted eagle-owl) collected within the Swartkrans cave for taxonomic, taphonomic, and paleoecological perspectives. Contrasting fossil and modern micromammalian data provide a better understanding of accumulation processes and facilitate a diachronic reconstruction of changes in climate and landscape evolution. Issues regarding paleoenvironmental reconstruction methodologies based on micromammals are also discussed.Item Developing a density functional theory model of glassy carbon via carbon defect induction and relaxation(Elsevier, 2025-01) Falch, A.; Meerholz, K.; van Sittert, C.G.C.E.Glassy Carbon (GC) is a non-graphitising carbon known for its thermal stability, conductivity, and resistance to chemical attack, making it valuable in industrial and scientific applications, especially as an electrode substrate in catalysis research. Despite its widespread use, GC’s precise structural characteristics is unclear due to synthesis variability. This study developed and validated a computational model to simulate GC’s structure. Starting from the R3-carbon allotrope, density functional theory calculations were used to construct a representative GC model, incorporating induced defects to mimic its structural imperfections. Multiple GC slab models were created for comparative analysis. Validation involved comparing theoretical X-ray diffraction data with published data, confirming the model’s accuracy in representing the GC’s structure. The model showed high correlation with existing models, particularly those by Jurkiewicz et al., emphasizing the effect of formation temperature on GC’s structural evolution. These findings enhance the understanding of GC’s structural complexities, providing a solid foundation for future research and applications in material science, especially for robust and conductive substrates used in electrocatalysis.Item Unprecedented Association: bilateral UPJ obstruction with grade 3 hydronephrosis caused by Type 2 circumcaval right ureter and left lower pole crossing vessels(Elsevier, 2025-01) Salem, Mohammed Salah E. Khalifa; Abdul, Alherek; DaSilva, Daniel; Mukendi, Alain Mwamba; Jacob, VargheseBilateral ureteropelvic junction obstruction resulting from distinct vascular anomalies on each side, with a preureteric vena cava on the right and crossing vessels on the left, has not been previously documented in the literature. Even more intriguing is the association between a grade 3 hydronephrosis and a type 2 circumcaval ureter. This unprecedented report discusses this association and its management.Item Time and frequency nexus among public debt, exchange rate, inflation, monetary policy rate and economic growth in Ghana(Elsevier, 2025-01) Owusu Junior, Peterson; Odoom, Absalom; Adu-Asare Idun, Anthony; Akorsu, Patrick KwashieThe debate about the influence of public debt on an economy has gained long-standing attention among policy-makers, regulators and academic scholars. The excessive expansion of Ghana’s public debt to GDP demands a fresh insight into the macroeconomic variables that are connected to economic growth. This study utilised wavelet techniques to investigate the nexus and effect of public debt, exchange rate, inflation rate, and monetary policy rate on economic growth in Ghana using monthly data from 2000 to 2022. Diks and Panchenko (2006) was used as a battery test for the wavelet results. We found a significant negative correlation between public debt and GDP at both short- and long-term frequencies, though there was no notable connection in the medium term. The causality analysis suggests a possibility of bidirectional causality between GDP and public debt in both the short and medium term. Interestingly, the COVID-19 pandemic had minimal impact on this relationship when comparing the pre-pandemic and during-pandemic periods. The only observed coherence (negative) between monetary policy and GDP occurred between 2000 and 2003, at low and medium frequencies. The WMCC results depicted that no variable was seen to lead or lag during the pandemic period however, GDP (exchange rate) reacted to shocks first (last) in the short run (long run) prior to the pandemic. The result of this research is crucial for policy implementation. The GDP-public debt negative nexus offers strong evidence for the government to make determined efforts to reduce external borrowing. The positive coherence of exchange rates and the public debt offers a strong incentive to the monetary authorities to make determined efforts to stop the rapid rise of exchange rates.Item Impact of witnessing abuse of their mother and childhood trauma on men’s perpetration of intimate partner violence in the cross-sectional UN multi-country study on men and violence in Asia and the Pacific(Elsevier, 2025-01) Jewkes, Rachel; Shai, Nwabisa; Chirwa, Esnat; Naved, Ruchira Tabassum; Abrahams, Naeema; Ramsoomar, Leane; Dekel, Bianca; Gibbs, Andrew; Nothling, Jani; Willan, SamanthaTrauma exposure and witnessing intimate partner violence (IPV) in childhood are recognised risk factors for IPV. Using the UN Multi-country Study on Men and Violence in Asia and the Pacific dataset, we describe the pathways through which they influence adult IPV perpetration. Methods: In nine sites, from six countries, data were collected in a two-stage, randomly-selected household survey, with one man aged 18–49 years interviewed per house. 8379 interviews were completed with ever partnered men in Bangladesh, Cambodia, China, Indonesia, Papua New Guinea (Bougainville) and Sri Lanka. We present a Structural Equation Model (SEM) to understand paths through which childhood trauma and witnessing IPV impacted perpetration of physical or sexual IPV in adulthood. Results: Among the men, 25.5% had witnessed IPV, 47.0% had perpetrated physical or sexual IPV. Both wit nessing IPV and childhood trauma elevated the likelihood of such perpetration. The SEM showed four paths from witnessing IPV and childhood trauma to the latent variable for physical/sexual IPV perpetration. One was direct and three indirect. Paths were mediated by food insecurity, depression, and a latent variable measuring gender inequitable and anti-social masculinities. The masculinity variable indicators were drug use, harmful alcohol use, bullying, gang membership, fighting with other men, having sex with a sex worker and having raped a non partner. The direct and indirect effects showed both childhood trauma and witnessing maternal IPV to be important, but childhood trauma the more so. Conclusions: Both childhood trauma and witnessing IPV were important in driving IPV perpetration, with in dependent effects, however, broader childhood trauma exposure was most strongly associated. The effects were mediated by food insecurity, depression and gender inequitable and anti-social masculinities, all recognised risk factors for IPV perpetration. Thus, gender transformative IPV prevention interventions that include mental health and economic elements can mitigate the influence of these key exposures.