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Item Assessing the influence of solid waste knowledge and concern on pro-environmental action in South Africa: Implications for waste management and circular economy strategies(2026-10) Haywood, Lorren K; Dunn, S; Oelofse, Suzanna HH; Roberts, BJThis study investigates public awareness, concern, personal pro-environmental norms, and household recycling behaviour in South Africa using data from the 2022 and 2024 rounds of the South African Social Attitudes Survey. The findings indicate that recycling behaviour remains limited, with approximately 30% reporting that they “always” or “often” recycle. Regression analyses show that environmental knowledge and waste-specific concern are positively associated with recycling behaviour, although these relationships explain only a modest proportion of the variation in behaviour. Environmental knowledge shows a relatively stronger association, while concern plays a more limited role once knowledge is accounted for, suggesting that awareness of recycling is an important, but not sufficient, influence on action. The association between personal pro-environmental norms and recycling behaviour is weak and inconsistent across survey years, indicating a context-dependent role. The results highlight a persistent gap between environmental awareness and consistent pro-environmental behaviour. In the South African context, this gap is shaped not only by behavioural factors but also by structural constraints, including uneven access to waste collection services, variability in municipal infrastructure, and differences in service delivery capacity across municipalities. The findings provide support for the Theory of Planned Behaviour and Value-Belief-Norm frameworks, while also showing that psychological drivers such as knowledge, concern, and norms are mediated by real-world conditions that influence perceived behavioural control and the translation of environmental values into action. Improving recycling outcomes in South Africa requires an integrated approach that combines behavioural interventions, such as strengthening environmental literacy and reinforcing pro-environmental norms, with systemic improvements in waste management infrastructure and service delivery.Item Mechanical property comparison of AISI 5120 steel produced by LENS and DMD systems(2026-06) Sibisi, TH; Mathoho, Ipfi; Shongwe, BS; Tshabalala, Lerato C; Skhosane, Besabakhe S; Motau, R; Mndebele, N; Vithi, NThis study presents a comparative investigation of the microstructure and mechanical properties of AISI 5120 low-alloy steel fabricated using two Directed Energy Deposition (DED) systems: Laser Engineered Net Shaping (LENS) and robotic Direct Metal Deposition (DMD). The objective was to evaluate process–structure–property relationships under optimized operating conditions representative of each system. Microstructural characterization was performed using optical microscopy and scanning electron microscopy (SEM), while tensile strength, microhardness, and Charpy impact toughness were evaluated according to ASTM standards. The LENS-fabricated samples exhibited a predominantly ferrite–pearlite microstructure and demonstrated higher surface hardness (217 HV) and superior impact energy (137 J). In contrast, the DMD specimens displayed refined microstructural features with bainitic-like characteristics inferred from SEM morphology and achieved significantly higher tensile properties, including an ultimate tensile strength of 754.3 MPa, yield strength of 675.97 MPa, and elongation of 17.63%. Fractographic analysis indicated ductile failure modes in both systems; however, LENS samples showed a higher qualitative presence of porosity. The improved tensile performance of the DMD system is attributed primarily to reduced porosity and enhanced interlayer bonding resulting from higher energy input and improved melt pool stability. While LENS provided enhanced surface hardness and impact resistance, DMD demonstrated superior overall mechanical integrity. The findings highlight the importance of system-level process optimization when selecting DED platforms for load-bearing or wear-critical industrial applications. Further investigation including fatigue testing, quantitative porosity analysis, and phase confirmation using diffraction techniques is recommended.Item Lasers in health care - How light is revolutionising medicine(2026) Thwala, Nomcebo L; Ramokolo, Lesiba ROnce confined to science fiction movies and high-tech laboratories, lasers are now playing an increasingly important role in healthcare. From precise surgeries to advanced diagnostic tools, laser technology is reshaping how we diagnose, treat and even prevent diseases.Item Workforce skills gaps and human-AI collaboration in adaptive factories(2026-05) Nelufule, Nthatheni; Siphambili, Nokuthaba; Shadung, Lesiba D; Senamela, Pertunia MThe transition from Industry 4.0 to Industry 5.0 has repositioned humans at the center of adaptive, resilient, and sustainable manufacturing systems. It has been projected that by then end of November 2025, over 68 % of global manufacturers will report lack of critical workforce skills that also impede full adoption of AI-enabled adaptive factories. In this article, a survey results on the nature, magnitude, and evolution of the lack of critical workforce skills, and the emerging paradigms of human-AI collaboration are presented. A PRISMA framework was used to synthesize peerreviewed articles between 2020 to 2026 to examine the existing dominant themes, ranging from technical deficiencies in AI literacy and data science to socio-emotional and creative skills required for effective robot interaction. The main research contribution in this article is the Human-AI Synergy Competency Framework, which is a multilevel, dynamic model that maps required competencies, assesses maturity, and prescribes personalized reskilling pathways using generative AI tutors and digital twins. This research has also revealed that current AI tutoring technologies have demonstrated faster upskilling of about 57 % and 28–54 % of productivity gains based on the simulated data. This article has also recommended the adoption of regulatory mandates particularly for the lifelong learning credits and enterprise adoption of Human-AI Synergy Competency Framework frameworks to reduce the projected global manufacturing talent shortfall of 8.5 million workers, by 2030.Item Removal of pharmaceuticals and personal care products in conventional and advanced wastewater treatment processes(2026-10) Kaium, A; Nocanda, Xolani W; Fick, JBWater scarcity and contamination of surface waters with chemicals and pathogens pose significant challenges to global public health. Effective wastewater treatment is essential to safeguard water quality for reuse and to protect the environment. Here, we analyzed influent and effluent samples from seven wastewater treatment plants in Durban, South Africa, employing conventional and tertiary treatment processes. Using advanced analytical methods, we quantified concentrations of 140 pharmaceuticals and personal care products, detecting 75 compounds in influents at elevated levels, including antibiotics and antivirals linked to regional health burdens. Average measured concentrations in the influents ranged from 19,000 ng l-1 to 6100 ng l-1, caffeine had the highest measured value (1,600,000 ng l-1). Removal efficiencies varied widely, between >95% to 30%, with tertiary treatments such as membrane filtration and advanced oxidation achieving superior reductions compared to conventional methods. These findings underscore the importance of advanced treatment technologies in mitigating pharmaceutical and personal care products pollution in wastewater effluents, informing strategies to enhance water reuse safety and addressing emerging contaminants in water-scarce regions.Item Zero trust for NHIs based on robust identity and access management for a resilient IoT future(2026-04) Mthethwa, S; Dlamini, Thandokuhle M; Jembere, EThe pervasive adoption of Internet of Things (IoT) devices has profoundly reshaped digital connectivity by enabling real-time data exchange and autonomous interactions on a global scale. While this transformation presents substantial operational benefits, it simultaneously introduces significant security challenges, especially in terms of Identity and Access Management (IAM) for non-human entities, such as sensors, devices, machine agents, and service accounts. Historically, traditional perimeter-based security models, which depend on static trust boundaries and implicit trust for internal actors, have been applied to human identities. However, these models prove inadequate for managing non-human identities. This inadequacy has spurred interest in Zero Trust Architecture (ZTA), an advanced security paradigm based on the principle of “never trust, always verify.” This paper examines the application of ZTA in safeguarding IoT ecosystems, with a particular emphasis on managing non-human identities. The study delves into ZTA’s fundamental principles, such as least privilege, micro-segmentation, continuous monitoring, and identity-centric access control, and evaluates their effective implementation in resource-constrained IoT settings. The research identifies critical implementation challenges and considerations for applying identity-based ZTA within IoT contexts. The findings of this paper underscore that ZTA, when meticulously implemented, provides a robust framework for mitigating the cyber risks inherent in IoT ecosystems. Furthermore, the paper delineates prospective research avenues aimed at integrating ZTA into IoT environments. Ultimately, this study contributes to the expanding body of scholarly knowledge by endorsing Zero Trust as a foundational strategy for contemporary IoT security.Item Nutritional composition, Β-carotene and vitamin a contribution of orange-fleshed sweet potato (OFSP) products from selected South African cultivars and beauregar(2026-05) Shikwambana, K; Mashitoa, FM; Melane, Pumeza P; Dlamini, Nomusa; Bairu, M; Chakauya, E; Laurie, SMVitamin A deficiency (VAD) is widely recognised as a major public health problem in sub-Saharan Africa (SSA). Orange-fleshed sweet potato (OFSP), rich in β-carotene, offers a sustainable food-based intervention strategy to address VAD. However, the nutritional contribution of OFSP products depends on cultivar characteristics, formulation and processing methods, which influence proximate composition and carotenoid retention. This study evaluated the nutrient content of various OFSP-products developed from South African sweet potato (SP) cultivars (Khumo, Bophelo) and USA cultivar Beauregard. Four OFSP products, including flakes, instant porridge, crisps and pasta, were developed, and proximate composition, β-carotene content and retinol activity (RAE) were determined. The contribution of each product to the recommended dietary allowance (RDA) for vitamin A was calculated across different age groups. Statistically significant differences (p < 0.001) were observed among OFSP-products. Moisture content ranged from 5.15 ± 0.03% to 9.68 ± 0.17%, protein from 2.18 ± 0.01% to 15.37% and fat from 0.74 ± 0.12% to 29.14 ± 0.29%. Carbohydrate was the major macronutrient, with energy values between 1527 ± 2.0 and 2113.3 ± 0.57 kJ/100 g. Furthermore, β-carotene ranged from 7.52 ± 0.09 to 22.56 ± 0.65 mg/100 g, equivalent to RAE values of 626.94 ± 7.87 to 1880.0 ± 54.16 µg/100 g. OFSP crisps retained the highest provitamin A, while instant porridge and pasta provided a balanced macronutrient profile due to composite formulation. This study demonstrated that 100 g of serving of OFSP flour or puree-based products could supply 100% of the vitamin A of RDA for children between 1–3, 4–8 and 9–13 years and pregnant women. These findings demonstrated that properly formulated OFSP products can serve as an effective, culturally adaptable vehicle for improving vitamin A intake and enhancing nutritional security.Item Can Sentinel-2-derived spectral indices improve the accuracy of retrieving optically active water quality parameters using machine learning algorithms?(2026-06) Rathupetsane, EM; Kganyago, M; Madonsela, Sabelo; Mvandaba, VuyelwaStudy region: This study was conducted in the Cradle of Humankind World Heritage Site (COHWHS), South Africa, an area characterised by interconnected surface waters and sensitive dolomitic aquifers. The region is subject to increasing pressure from land use change, tourism, and nutrient enrichment, making reliable and spatially explicit water quality monitoring essential for protecting its ecological, cultural, and hydrological integrity. Study focus: The study aimed to assess whether Sentinel-2-derived spectral indices improve the retrieval accuracy of optically active water quality parameters, namely Chlorophyll-a (Chl-a) and Total Suspended Solids (TSS). Three input configurations were tested: traditional Landsat-like bands, Sentinel-2 bands, and Sentinel-2 bands combined with spectral indices. These inputs were used within Random Forest and Gaussian Process Regression models to evaluate model performance across wet (summer) and dry (winter) seasons. New hydrological insights for the region: The results show that integrating Sentinel-2 spectral indices substantially improves Chl-a estimation during wet conditions, while TSS retrieval benefits mainly from Sentinel-2 red, red-edge, and SWIR bands. Model performance was strongly seasonal, with reduced accuracy during dry periods due to lower optical variability. The findings provide new insight into how seasonal hydrological conditions and spectral sensitivity influence water quality retrievals in optically complex inland waters of the COHWHS. This approach supports improved regional water quality monitoring and contributes to the protection of connected surface water-groundwater systems in this vulnerable heritage landscape.Item Spatial and temporal resolution effects on object-based mapping of termite mounds(2026-05) Maponya, MG; Mashimbye, ZE; Clarke, CE; Cho, Moses ABiogenic mounds play a crucial role in shaping soil salinity patterns, carbon storage, nutrient redistribution, and rangeland functioning, making accurate information on their spatial distribution essential for effective ecosystem management. This study investigates the impact of spatial and temporal resolution on the mapping accuracy of termite mounds using remote sensing imagery. Mapping performance was evaluated using object-based image analysis combined with machine learning across multi-resolution datasets, including GeoEye-1, aerial imagery, and Sentinel-2. Two experimental designs were implemented to quantify resolution-driven differences in detection accuracy. The first set of experiments evaluated the effect of temporal resolution with 1) a seasonal Sentinel-2 image composite (June to August 2019), 2) a monthly Sentinel-2 image composite (June 2019), and 3) a single date Sentinel-2 image (June 2019). The second set of experiments assessed the impact of spatial resolution using 1) Geoeye-1 imagery, 2) aerial imagery, and 3) Sentinel-2 imagery. Classification results were analysed by comparing overall accuracies (OA) and kappa coefficients, with McNemar’s test used to assess the statistical significance of accuracy differences among experiments. Results indicated that very high spatial resolution images (Geoeye-1 and aerial) based on GEOBIA and SVM allow for the classification of termite mounds with accuracies exceeding 95%. Although lower spatial resolution evidently decreased classification accuracy, increasing temporal resolution can minimise these limitations. This is demonstrated by the 10.4% and 10.8% improvements in overall accuracy (OA) using seasonal (91.1%) and monthly (90.7%) Sentinel-2 composites compared to a single-date Sentinel-2 image (80.3%).Item Not all CO2 is equal: Source-specific constraints and viability trade-offs in methanol synthesis from industrial emissions(2026-05) Macheli, L; Mukeru, BM; Duma, Zama G; Patel, B; Jewell, LLMethanol synthesis from captured CO2 is widely regarded as a promising pathway for carbon utilization, yet its feasibility depends heavily on the characteristics and constraints of the CO2 source. This review evaluates four industrial point sources—biogas, steel plants, cement kilns, and waste-to-energy facilities—highlighting key differences in CO2 purity, contaminant load, hydrogen integration, and catalyst stability. We propose a five-axis viability framework, developed through a synthesis of current literature, to structure source-specific comparison and guide system-level evaluation. The framework includes CO2 usability, hydrogen vulnerability, contaminant burden, integration potential, and policy exposure. By applying this structured lens, the review identifies key performance-limiting trade-offs, techno-economic constraints, and integration barriers across point sources. Results show that biogas and steel off-gases offer favourable trade-offs (scores of 15–18/25), while cement and waste-to-energy streams face major integration and degradation challenges (≤9/25). Reforming pathways, gas conditioning requirements and modular deployment considerations are also discussed. This review concludes that effective CO2-to-methanol deployment requires source-specific process design, improved ontaminant-tolerant catalysts, and better alignment of infrastructure and policy to the heterogeneous nature of industrial CO2 sources.Item Microstructure, phase stability, and mechanical properties of binary Ti-Mo and ternary Ti-Mo-Fe alloys for biomedical applications(2026-03) Moshokoa, NA; Makhatha, ME; Raganya, Mampai L; Makoana, Nkutwane W; Phasha, M; Moema, JMetastable β-Ti alloys with non-toxic and low-cost alloying elements, with high biocompatibility and improved mechanical properties, are being developed globally for biomedical applications. Howerver, there is still limited published work on Ti-Mo and Ti-Mo-Fe alloys with high Mo content and low cost alloying element with high strength designed for biomedical applications such as vascular stents. Thus, the current study uniquely investigates the combined influence of Fe addition and theoretical methods on β stability and mechanical performance of Ti-Mo alloys with high Mo content vascular stents. Two metastable β-Ti alloys, namely, binary Ti-20Mo wt% (referred to as Alloy 1) and ternary Ti-16.5Mo-1.1Fe wt% (referred to as Alloy 2), were designed using the theoretical predictive methods such as the molybdenum equivalence (Moeq), the average Bo-Md method, and the electron-to-atom ratio (e/a). Microstructural characterization and tensile properties of the alloys after solution treatment at 1100 °C and quenched in ice-brine were analysed. The X-ray diffraction (XRD) patterns and optical micrographs showed stability of the β phase in both alloys due to similarity in e/a ratio value and a slight difference in Moeq. Alloy 1 showed a high ultimate tensile strength (UTS) of 920 MPa and yield strength (YS) of 906 MPa, whereas a much lower UTS of 540 MPa was observed in Alloy 2. The elastic modulus decreased from 85 GPa in Alloy 1 to 74 GPa in Alloy 2, while micro-Vickers hardness increased significantly from 353 Hv0.5 in Alloy 1 to 428 Hv0.5 in Alloy 2. The high strength and modulus in Alloy 1 illustrated that the alloy could be considered as a potential alloy for biomedical applications such as those in vascular stents.Item Additively manufactured carbide and nitride doped Co22.2Cr22.2Ni22.2Cu22.2Nb11.2 high-entropy alloy for surface engineering application(2026-06) Alabi, AS; Popoola, API; Popoola, OM; Mathe, Ntombizodwa RMetal-matrix composites have gained wide recognition owing to their superior tailorability, which surpasses that of traditional alloys. The development of multicomponent metal-based high-entropy alloy (HEA) systems has increased the potential for fabricating tunable composites for surface engineering applications. It has been established that the intrinsic properties of the composites are determined by the phases present in their base alloys, reinforcement types, and volumes. Herein, 5 wt% of vanadium carbide, titanium nitride, and a combination of both ceramics were added to Co22.2Cr22.2Ni22.2Cu22.2Nb11.2 HEA and fabricated via directed-energy deposition. The investigation highlights the first-time use of both ceramics and their synergistic utilisation as hybrid reinforcement in the directed-energy-deposited HEA. The candidate with the best hardness, tribological properties, and corrosion resistance was identified after various characterisations. It was found that the composite reinforced with a combination of both ceramics had the best microhardness value of 736 ± 30.79 HV. The titanium nitride-reinforced composite exhibited the highest wear resistance with 6.69 × 10⁻⁶ mm³ /Nm at 20 N applied load. However, the synergy of both reinforcements offers enhanced lubricity, resulting in the lowest coefficient of friction of 0.071. A worn track analysis revealed that the samples were characterised by a transition from severe adhesive wear to cold-welded tribo-layer formation. The unreinforced HEA demonstrated the highest corrosion resistance with 567.79 Ω polarisation resistance and a corrosion rate of 0.6909 mm/year. It was concluded that the developed HEA and its composites are promising candidates for surface engineering application.Item Exploring the utility of a multivariate soil hyperspectral reflectance model for estimating soil moisture using sentinel-2 Data(2026-05) Atyosi, Yonwaba; Cho, Moses A; Majozi, Nobuhle P; Bonnet, Wessel J; Ramoelo, AAccurate and spatially transferable estimation of soil moisture is critical for sustainable agriculture, water resource management, and drought monitoring, particularly in data-scarce semiarid regions. However, soil moisture retrieval from optical satellite data remains challenging due to heterogeneous soil conditions and limited model generalizability, especially when interactions between soil moisture and clay content are neglected. This study presents a physically informed, simulation-based multivariate framework for estimating soil moisture from freely available Sentinel-2 multispectral imagery that explicitly accounts for soil clay content and its interaction with moisture. A Monte Carlo look-up table comprising 100,000 synthetic soil reflectance spectra was generated under varying soil moisture and clay conditions and resampled to Sentinel-2 spectral bands. Soil moisture-sensitive spectral band combinations, ratios, and newly developed soil moisture indices were derived and used to train machine learning models, which were evaluated using group-aware cross-validation to assess spatial robustness and transferability. Model application across multiple agricultural sites in South Africa’s Eastern Cape and Limpopo provinces, regions geographically distinct from calibration areas and spanning contrasting ecological and climatic conditions demonstrated high predictive performance (R² up to 0.91; RMSE as low as 0.71) and strong spatial transferability. The results indicate that explicitly integrating soil property interactions within a synthetic spectral modeling framework substantially improves Sentinel-2–based soil moisture estimation. The proposed approach advances operational optical remote sensing of soil moisture by bridging physically consistent spectral simulations and scalable multispectral observations, providing a transferable methodology for precision irrigation, drought early warning, and sustainable agricultural water management in semiarid environments.Item Green synthesis of crystalline silicon nanoparticles (SiNPs) via magnesiothermic reduction of mesoporous silica extracted from sugarcane bagasse ash (SCBA)(2026-11) September, LA; Kheswa, N; Seroka, Ntalane S; Khotseng, LIn this study, crystalline silicon nanoparticles (SiNPs) were successfully produced utilising a low-temperature magnesiothermic reduction method of mesoporous silica nanoparticles (SiO2NPs). Silicon nanoparticles (SiNPs) have gained attention in recent years due to their range of applications and specific properties. However, producing high-purity SiNPs necessitates high-energy production, such as carbothermic reduction at >2000 °C, in addition to the significant pollutants and CO2 emissions generated throughout the process. Thus, there has been an increase in research on extracting SiNPs from various agricultural wastes as a cost-effective source. This study investigates the extraction of SiO2NPs using sol-gel synthesis from sugarcane bagasse ash (SCBA) and resulted in a purity of 94.8% utilising XRF. After magnesiothermic reduction of SiO2NPs at 650 °C, XRD and Raman confirmed the resulting crystalline SiNPs. Furthermore, SEM and TEM were used to investigate the morphology along with BET to determine specific surface area, pore volume, and pore diameter, which resulted in 57.85 m2/g, 0.18 cm3/g, and 12.4 nm, respectively, for the produced SiNPs. Additionally, this study includes the use of a green-sustainable synthesis method to decrease energy usage and attempts to replace toxic counterparts with reagents such as the use of L-cysteine hydrochloride monohydrate and citric acid, while obtaining high-purity SiNPs. SiNPs have a variety of possible applications in new advancements, including energy production like solar photovoltaic cells and energy storage devices, which contribute towards the UN's sustainable development goals (SDG), particularly SDG 7 (Affordable and clean energy) and SDG 13 (Climate Action), as this study exhibits sustainability and increases the potential to reduce biomass waste production.Item Recent advancement and prospects of graphite nanocomposites as anode materials for lithium-ion batteries(2026-09) Seroka, Ntalane S; Modibedi, Remegia M; Zheng, Haitao; Khotseng, L; Luo, HongzeRechargeable batteries in the energy storage sector are seen as both current and future critical energy production and storage technologies. They are essential in the day-to-day of hybrid and electric vehicles, given their reliable sustainability and performance metrics amongst energy storage technologies. The pertinent challenges such as flammable electrolytes, safety concerns, costs, and environmental recovery impede their widespread adoption in energy storage efficiency, i.e lithium-ion batteries. This study gives key insights on lithium-ion batteries that are not limited to reaction mechanisms, storage mechanisms, material development, structural features, and preservation. Provides key aspects in optimal solid electrolyte interfaces and graphite intercalation compounds; investigates innovative materials such as biochar, as well as their composites with graphite. The review delves into reaction mechanics and kinetics in rechargeable batteries and current trends in the advancement of these technologies. Lithium-ion storage in graphite, and nanocomposites with factors influencing oxygen defects, interlayer spacing, and stacking attributes. These structural and morphological properties affect the diffusion pathways within the expansive framework pores of lithium ion, these defects, and in addition improve the surface area. The structural, morphological, and textural and their synergistic effects on the overall performance metrics are also discussed in the paper.Item A review of failure mechanisms and advanced remanufacturing technologies for gears and sprockets in mining machinery(2026-03) Belete, MB; Omogbehin, GS; Regesa, AI; Setswalo, K; Leso, TP; Satya, PRV; Olakanmi, EO; Botes, A; Ndeda, R; Pityana, Sisa L; Ematang, NYThis review systematically identifies, quantifies, and synthesizes the failure modes of heavy-duty gears and sprockets in mining equipment, examines their underlying causes or contributing factors, and evaluates remanufacturing strategies to enhance component durability. Despite the critical role of these drivetrain components, the number of mining-specific studies is limited, making this synthesis essential for understanding trends, informing practical interventions, and proposing further research areas. Analysis of the literature indicates that tooth fracture dominates gear failures, representing approximately 75% of reported cases in open-pit mines, primarily due to extreme shock loads, and 50% in underground mines, driven by fatigue and contamination. In contrast, abrasive wear is the primary mode of sprocket degradation (> 60% in both mining environments), resulting from continuous exposure to abrasive particulates, moisture, and high-humidity conditions. Manufacturing-induced defects, particularly quenching micro-cracks and unfavorable residual tensile stresses from conventional heat treatments, emerge as a primary contributor to premature failures, independent of operational conditions. Advanced remanufacturing techniques provide targeted solutions for these recurring failures. Laser cladding using wear-resistant iron-based matrix metal composites (IMMCs) enables precision restoration of gear teeth, while wire-arc additive manufacturing (WAAM) is well-suited for repairing extensively fractured components. By integrating insights on failure mechanisms, operational environments, and remanufacturing effectiveness, this review bridges critical gaps in mining-specific knowledge of component degradation and restoration. The synthesis offers actionable guidance for extending the service life and improving the operational reliability of heavy-duty mining drivetrain components.Item A Retrospective on South Africa’s Student Cluster Competition and its Model for Inclusive HPC Outreach and Training (2012-2020)(2026-03) Johnston, Bryan J; Thorne, N; Cawood, M; De Beste, E; Macleod, David N; John Poole, JThe Centre for High Performance Computing (CHPC) is South Africa's national supercomputing facility. In 2012, it launched an outreach initiative to raise awareness of High-Performance Computing (HPC) among undergraduate students through the creation of the Student Cluster Competition (SCC). A national contest was designed to train and showcase student talent in a spirited, hands-on environment. The initial stage of the CHPC SCC saw twenty teams of four undergraduate students undergo an intensive week of HPC training, covering Linux fundamentals, cluster design, and system administration. Finalists from this selection round would then compete in a live challenge using HPC systems of their own design, with the top competitors selected to represent the CHPC at the International Student Cluster Competition hosted at the ISC High Performance conference in Germany. From its inception, the CHPC SCC has prioritised demographic diversity and equal opportunity, actively recruiting students from historically disadvantaged communities to ensure inclusive participation and representation. A rapid teaching framework was developed to address key knowledge gaps in HPC system design, administration, and optimisation: the empowerment of students with limited prior exposure in the field of HPC to excel. This approach has proven highly effective: South African teams ranked in the top three internationally for eight consecutive years, demonstrating the strength of the program. This paper presents the strategy and structure behind the CHPC SCC, detailing the training model, selection process, and evaluation methods used for both national and international rounds. It highlights how the initiative has evolved into a recognised platform for HPC education, enabling students to learn about HPC and become global contenders in the field.Item Editorial: Framing extreme weather and climate: Anomalous meteorological events (AMEs)(2026-03) Sweijd, N; Sarvajayakesavalu, S; Charlotte McBride, C; John, JuanetteIn May of 2024, a set of researchers, practitioners and officials gathered in Stellenbosch, South Africa to confer on Integrated responses to the intensification of extreme climate and weather events in developing economies. The event, co-sponsored by the Government of South Africa, the Centre for Science & Technology of the Non-Aligned & other Developing Countries, the Scientific Committee on Problems in the Environment (SCOPE) and Stellenbosch University, was attended by over 100 delegates from 11 different countries. As one of the outcomes of this meeting, Environmental Development has produced a series of peer-reviewed research papers emanating from the meeting presentations. Key points that emerged from discussions at the event are noted, followed by the features of this Special Issue. The phrases “Extreme Climate Events” or “Extreme Weather Events” are now common parlance in the field of climate research. However, to address the growing need to understand and manage these phenomena, it is essential to clearly define and specify this terminology, ensuring that we have agreement on how new knowledge in this area is acquired and applied.Item Quantifying the extent and rates of change in wetland ecosystem functional groups in the Maputaland Coastal Plain of South Africa(2026-05) Van Deventer, Heidi; Apleni, P; Naidoo, L; Tsele, PDespite global concerns highlighting the threats to wetlands, monitoring and quantifying changes in palustrine wetland ecosystem extent remains inadequate. The feasibility of mapping the extent and rates of change of wetland Ecosystem Functional Groups (EFGs) in the Maputaland Coastal Plain, South Africa, using Earth Observation (EO) was evaluated. Seven wetland EFGs were mapped, including two estuarine (Coastal saltmarshes, and Intertidal forests and shrublands (mangroves)) and five freshwater EFGs (Lacustrine wetlands and palustrine wetlands: Large macrophytes, Permanent marshes, Seasonal marshes, and Subtropical-temperate forested wetlands). Changes in their extent were quantified across seven epochs across a 32-year period (1990–2022), including three above-average rainfall years (2000, 2006, and 2022), and four years that corresponded with the South African National Land Cover datasets (SANLCs: 1990, 2014, 2018, and 2020). Landsat images between 1990 and 2014 and a combination of Sentinel-1 and -2 images between 2018 and 2022 were modelled with a Random Forest classifier using EFG reference spectra informed by fieldwork. The classifications achieved overall accuracies between 78% and 87%, with user accuracies of the EFGs ≥ 73% for all years. Over the last 32 years, 53% of the extent of wetland EFGs remained unchanged, whereas 35% experienced interclass transformation and 8% were converted to anthropogenic pressures (5% speckle ignored). Four of the wetland EFGs showed an annual decline of 1% to 3%. Projections indicate that, under current conditions, four EFGs could face total collapse by 2050, with Intertidal forests and shrublands at the highest risk. The findings highlight the need for enhanced EO-based monitoring and protective measures to preserve wetland biodiversity and its ecosystem services.Item A review of feedstock diversification for methanol production: From fossil fuels to renewable resources(2026-03) Reddy, Trishen; Seodigeng, TMethanol is a critical platform chemical and an increasingly important energy carrier. While global production is currently dominated by fossil-based pathways primarily natural gas (average 65%) and coal (average 35%), there is however an urgent industrial mandate to decarbonize the supply chain. This review provides a rigorous quantitative evaluation of conventional and emerging carbonaceous feedstocks, including biomass, agricultural residues, municipal solid waste, and captured carbon dioxide (CO2). Quantitative analysis reveals that while traditional biogas offers methane concentrations averaging 50–80%, emerging substrates can also provide superior methane yields. A significant contribution of this work is the integration of the latest 2025 findings on semolina processing waste, which demonstrates a high-hydrogen (H2) potential (average 23.0% H2) for biomethanol synthesis. Furthermore, the paper delves into the relevance of process intensification, identifying membrane reactor technology as a primary solution to thermodynamic equilibrium constraints. By addressing critical technical hurdles such as membrane fouling often cited as a major barrier to the 0.2% renewable share in global supply. This review serves as a vital roadmap for industries aiming to transition toward carbon-negative methanol production and enhanced energy resilience.