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The making of a (wild) fish
No full textIn this article, which draws on experiences of having observed Martin Davies’s trout egg and milt collection at Thrift Dam in the Eastern Cape, South Africa, interviews with Davies himself, theoretical literature on fish breeding, genealogy, animal history, science studies, legislation on genetic manipulation, literature on notions of wildness and domestication, and actually fly-fishing at venues stocked with Davies’s fish, the article’s authors consider the possibilities and paradoxes involved in the historical-biological “making” of a fish: a fish in process for more than thirty years, described by its(co)maker as “totally wild.” The article explores the question: Can one make a “wild” fish? The question is not entirely new, as there are extensive debates in animal and environmental studies about wildness. The process of answering that question leads the article’s authors to the core of Anthropocenic debates about interspecies relationships, distinctions between the domesticated and the wild, the biology and ethics of genetic manipulation, and even the limits of the human. These issues have been well explored by many scholars, but this article’s authors engage with them from the specificities of fish and their bodies, which, with the fluidity of their environment and their inherent, elusive slipperiness, frequently evade conceptual or physical capture. In particular, the case that the article’s authors consider raises challenging questions about human and nonhuman agency: Can a body of water and its multiple constituents be actors? Can fish which cannot breed “naturally” be agents in their own remaking? Can one make a fish for and with a specific environment? Are “natural” and “human” selections necessarily irreconcilable? And so on. As Claude LéviStrauss famously said, animals are good to think with. In this case, trout disturb the waters
Value-adding effect of foreign direct investment inflow on manufacturing: evidence from South Africa
No full textThe manufacturing sector drives economic growth and structural transformation by fostering job creation, innovation and exports. Achieving and sustaining high-income status is challenging without manufacturing development, except for oil-rich nations and small financial hubs. Existing studies have overlooked the relationship between foreign direct investment and manufacturing value-added in emerging markets such as South Africa. This investigation examines the influence of foreign direct investment on manufacturing value added in South Africa. We utilised annual data from 1970 to 2020 and analysed them using linear and nonlinear autoregressive distributed lag (ARDL and NARDL) models to account for possible asymmetric effects. The ARDL analysis reveals that both foreign direct investment inflow and domestic investment negatively impact manufacturing value added in the short and long runs. Under asymmetry analysis, adverse shocks to foreign direct investment negatively affect manufacturing value added more than positive shocks. Positive and negative shocks in trade openness significantly boost MVA, highlighting globalisation’s role in economic growth. These findings underscore the nuanced dynamics between investment flows, trade openness and manufacturing performance. By incorporating asymmetric effects, our study provides new insights for policymakers. The results suggest that strengthening domestic resources mobilisation can support manufacturing growth, reduce reliance on external capital inflows and mitigate vulnerabilities linked to geopolitical risks
Characterization of new pyrone-containing flavones from Helichrysum petiolare Hilliard & B.L. Burtt
No full textHelichrysum petiolare Hilliard & B.L. Burtt. (Asteraceae), native to the Cape Floral Region of South Africa, is traditionally used in the management of wounds, respiratory complaints, and diabetes. Although extensive studies on its extracts, few have focused on the bioactivity of the individual phytochemicals. In this study, chromatographic processing of the H. petiolare leaf total extract led to the isolation and identification of ten compounds C1–C10) using NMR, FTIR, and HRESIMS spectroscopy. Two pyrone-containing flavones (C1 and C2) are reported for the first time from natural sources. The known compounds identified included flavonoids (C3–C5), phenolics (C6–C9), and a sterol (C10). The MTT assay revealed dose-dependent cytotoxicity of C1–C4 only against MDA-MB-231 (breast cancer), HeLa (cervical cancer), and HEK-293 (non-cancerous kidney) cell lines after 24 h exposure. Notably, C4 demonstrated selective activity toward HeLa cells (45 % viability reduction at 100 µM; IC₅₀ = 89.19 µg/mL). This is the first report of compounds C1–C10 from H. petiolare and their in vitro cytotoxic profile. Despite moderate activity, this work provides a foundation for further pharmacological investigations of derivatives of these metabolites in cancer management
The effect of garcinia livingstonei aqueous leaf extract on hyperglycaemic-induced human sperm cell: An in-vitro study
No full textHyperglycaemia is the main instigator of the development of male infertility in men with diabetes mellitus (DM). The consequent production of excessive reactive oxidative species (ROS) and a compromised antioxidant defence system leads to testicular damage and a decline in sperm parameters. Supplementation with antioxidants sourced from medicinal plants is beneficial in the treatment of DM-related male infertility. However, a search for more efficacious and easily accessibly medicinal plants is paramount. Garcinia livingstonei is a well-known and accessible medicinal plant used in traditional practices for the treatment of diabetic complications. However, very scarce information on the plant extract's potential benefits exists in the literature. The current study investigated the effect of aqueous leaf extract of G. livingstonei on hyperglycaemic human male sperm cell parameters. Hyperglycaemia was induced using sperm media supplemented with 100 mM D-glucose over 24 h. Hyperglycaemia induction led to a significant (P<0.05) decline in sperm motility, vitality, DNA integrity, mitochondrial membrane potential (MMP), and acrosome integrity. The effect of the plant extract on spermatozoa was concentration-dependent, with the lowest concentration demonstrating the highest protective effects. A significant (P<0.05) improvement in all tested sperm parameters was observed after exposure of the hyperglycaemic spermatozoa to aqueous leaf extract of G. livingstonei. The effect of acarbose on all tested sperm parameters was comparable to that of the plant extract. The findings of this study suggest the potential therapeutic effect of G. livingstonei in the treatment of DM-related male infertility. However, the use of an appropriate dosage depending on the pathological target is paramount
Fast and accurate stellar mass predictions from broad-band magnitudes with a simple neural network: application to simulated star-forming galaxies
No full textA simple, fully connected neural network with a single hidden layer is used to estimate stellar masses for star-forming galaxies. The model is trained on broad-band photometry-from far-ultraviolet to mid-infrared wavelengths-generated by the Semi-Analytic Model of galaxy formation (shark), along with derived colour indices. It accurately reproduces the known shark stellar masses with respective root-mean-square and median errors of only 0.085 and dex over the range - M. Analysis of the trained network's parameters reveals several colour indices to be particularly effective predictors of stellar mass. In particular, the colour emerges as a strong determinant, suggesting that the network has implicitly learned to account for attenuation effects in the ultraviolet bands, thereby increasing the diagnostic power of this index. Traditional methods such as spectral energy distribution fitting, though widely used, are often complex, computationally expensive, and sensitive to model assumptions and parameter degeneracies. In contrast, the neural network relies solely on easily obtained observables, enabling rapid and accurate stellar mass predictions at minimal computational cost. The model derives its predictions exclusively from patterns learned in the data, without any built-in physical assumptions (such as stellar initial mass function). These results demonstrate the utility of this study's machine learning approach in astrophysical parameter estimation and highlight its potential to complement conventional techniques in upcoming large galaxy surveys
Decolonising forensic odontology in Sub-Saharan Africa
No full textForensic odontology plays a vital role in human identification, age estimation, and legal investigations. However, in Sub-Saharan Africa, the field has developed within a framework shaped by colonial histories, Western methodologies, and systemic underinvestment in local capacity. This article critically examines the need to decolonise forensic odontology in the region, proposing a comprehensive reform agenda grounded in four intersecting domains: historical legacies, indigenous knowledge integration, ethical considerations, and policy reform. It highlights how colonial-era forensic practices continue to influence current protocols and legal standards, often to the detriment of scientific accuracy and justice. By recognising and incorporating traditional dental knowledge, such as ritual dental modifications and community oral histories, the field can be enriched and made more contextually relevant. Ethical challenges surrounding data sovereignty, informed consent, cultural sensitivity, and the use of contested techniques are addressed, with recommendations for more equitable and transparent forensic practices. Policy reforms are proposed to institutionalise forensic odontology through education, infrastructure development, legal recognition, and collaborative networks. The article argues that decolonisation is not a rejection of global science but a reorientation toward context-appropriate, ethically grounded, and locally led forensic systems. Through these reforms, Sub-Saharan Africa can build a forensic odontology discipline that is scientifically robust, culturally responsive, and capable of delivering justice and dignity to affected communities
A good reputation must be earned, but how? Examining the role of relationship communication and employee skills in retail banking
No full textThis study examines relationship communication and employee skills as antecedents to corporate image and the latter’s relationship with corporate reputation. It also considers the mediating role of corporate image and moderating roles
of customer characteristics, such as duration of support and customer spending. Using purposive and quota sampling, responses were collected from 352 customers of South African banks using a self-administered questionnaire. Mplus version 8.5 tested the direct effects proposed, while the indirect effects were tested with the Hayes Process macro for SPSS. The study assists emerging market banks to understand how corporate image influences corporate reputation perceptions, based upon the inclusion of selected corporate image antecedents. It also emphasizes the importance of duration of support and monthly spending in the relationships between corporate image and its selected antecedents
A study exploring procedures used to select and analyse microenterprises for persons with disabilities
No full textBackground Attaining the United Nations’ 2030 Sustainable Goals, such as fighting poverty and involving adults in work, requires the involvement of professionals such as occupational therapists. Persons with disabilities are among the adults to whom occupational therapists provide work or vocational rehabilitation services for productivity and well-being. Occupational therapists have skills such as analysing tasks to determine associated demands and requirements. The analysis ensures task feasibility, suitability, and matching of persons with disabilities. However, anecdotal evidence indicates that occupational therapists lack a systematic and practical approach to select and analyse suitable microenterprises for individuals with disabilities they serve. The objectives of this study were to address the gap in occupational therapy by exploring the i) selection of a suitable microenterprise for persons with disabilities and ii) factors to consider when analysing microenterprises to ensure successful outcomes. Thus, this study aims to explore procedures used to select and analyse microenterprises for persons with disabilities. Methods Seventeen participants participated in this exploratory qualitative research, three male. They were occupational therapists based in academia, clinical settings and learners with Special Education Needs Schools, respectively. Purposive and snowball sampling were used to recruit the participants. Data was analysed using thematic analysis using the hybrid inductive and deductive approach. Ethical clearance was issued by the University of KwaZulu-Natal’s Biomedical Research Ethics Committee. Results Two themes emerged. Theme one: The process of selecting an appropriate microenterprise. This theme describes the participant’s insight into the approach to microenterprise selection, the use of the microenterprise list or options available, and the distinct features of these microenterprises. Theme two: Factors to consider when analysing a suitable microenterprise as a placement option. The theme explores microenterprise accessibility, the key role players involved, business demands, and funding availability and access. Conclusion/discussion/interpretation For microenterprise selection and suitability analysis, a comprehensive, systematic and contextualised approach is crucial to facilitate self-employment as a viable career choice. Such includes integrating a list of microenterprises found in South Africa for career choice consideration. Moreover, there are essential factors for consideration, including the involvement of various key role players, legal and regulatory frameworks, funding sources and leveraging the strengths of persons with disabilities. These factors, effectively integrated with occupational therapists’ expertise in vocational rehabilitation, can enhance the vocational success of persons with disabilitie
A study exploring procedures used to select and analyse microenterprises for persons with disabilities
No full textBackground Attaining the United Nations’ 2030 Sustainable Goals, such as fighting poverty and involving adults in work, requires the involvement of professionals such as occupational therapists. Persons with disabilities are among the adults to whom occupational therapists provide work or vocational rehabilitation services for productivity and well-being. Occupational therapists have skills such as analysing tasks to determine associated demands and requirements. The analysis ensures task feasibility, suitability, and matching of persons with disabilities. However, anecdotal evidence indicates that occupational therapists lack a systematic and practical approach to select and analyse suitable microenterprises for individuals with disabilities they serve. The objectives of this study were to address the gap in occupational therapy by exploring the i) selection of a suitable microenterprise for persons with disabilities and ii) factors to consider when analysing microenterprises to ensure successful outcomes. Thus, this study aims to explore procedures used to select and analyse microenterprises for persons with disabilities. Methods Seventeen participants participated in this exploratory qualitative research, three male. They were occupational therapists based in academia, clinical settings and learners with Special Education Needs Schools, respectively. Purposive and snowball sampling were used to recruit the participants. Data was analysed using thematic analysis using the hybrid inductive and deductive approach. Ethical clearance was issued by the University of KwaZulu-Natal’s Biomedical Research Ethics Committee. Results Two themes emerged. Theme one: The process of selecting an appropriate microenterprise
Drivers, barriers and enablers of a South African circular solar pv module supply chain: a focus on reuse
No full textEnd-of-life (EOL) solar photovoltaic (PV) module waste is a pressing issue, given the expansion of solar PV adoption and the burgeoning number of modules that will enter EOL in the next decade. The drive towards reuse is that it could offer a means to retain the value in PV modules, reduce pollution, bring renewable energy (RE) closer to the average household and offset the costs of recycling. Primary research was undertaken on the perceptions of actors along the South African PV value chain. Interviews were held with key informants in energy and e-waste, and a questionnaire was administered to the solar sector. The findings were interpreted in terms of drivers, barriers and enablers of a PV module circular economy with a specific focus on reuse. The study found that the key enablers were enforcing existing environmental legislation, which includes a mandatory Extended Producer Responsibility (EPR) system, employing EPR fees towards waste system interventions and establishing quality assurance of second-hand products through testing and standards. Barriers to reuse were identified as being complex trade-offs between reuse, recycling and design, as well as the need for international standards and ensuring the market demand and viability of second-life modules. Research on higher-order circular economy activities, such as reuse and repair, has been limited in developing countries, including South Africa. The study adds to the body of knowledge in providing a potential framework for the development of a circular economy for PV modules in South Africa and offers broad policy recommendations for reuse