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Item Time-Interleaved noise jamming(2022-12) Claasen, Gert; Du Plessis, Warren PModern jamming systems are faced with the reality that multiple threat radars will be encountered simultaneously, and potentially, all simultaneously encountered threat radars will need to be countered to prevent detection. Modern jammer systems are capable of extremely rapid reconfiguration, allowing them to counter multiple simultaneous threats in a time-interleaved manner. However, simultaneously encountered threats cause jamming pulses to coincide in time, leading to the problem of deciding which of the threats to jam when such coincidences occur. In this article, an approach to determining the relative priority of jammer pulses is proposed and evaluated to show that time-interleaved jamming is a viable approach to effectively countering multiple simultaneous threats.Item A blockchain-based bimodal voter accreditation system (Block-BVAS): A framework for adoption in electronic voting systems(2026-08) Ohize, HO; Onumanyi, Adeiza James; Ajao, LA; Umar, BU; Ijalija, JM; Olosunde, SA; Abdullahi, AO; Olaniyi, OMDespite significant advances in electronic voting technologies, voter accreditation in many electoral systems remains vulnerable to identity fraud, database tampering, equipment failure, and centralized security breaches. Existing accreditation solutions often rely on single-modal biometric authentication and centralized architectures, limiting their robustness, transparency, and public trust. This paper proposes a Blockchain-based Bimodal Voter Accreditation System (Block-BVAS), together with a practical framework for its deployment in electronic voting systems. The proposed system integrates multimodal biometric authentication using facial and fingerprint recognition with a private Ethereum blockchain and conventional cryptographic mechanisms to provide secure, tamper-resistant, and auditable voter accreditation to provide secure, decentralized, and tamper-resistant voter accreditation. A Raspberry Pi 5 serves as the embedded processing platform, demonstrating the feasibility of implementing the framework on cost-effective hardware. By combining distributed-ledger technology with encrypted biometric verification, the proposed architecture enhances the integrity, confidentiality, and immutability of election-related records while addressing limitations associated with single-factor authentication and conventional centralized record management. Experimental evaluation of the biometric authentication module performed effectively, with fingerprint recognition achieving an average authentication accuracy (AA) of 97.8% and facial recognition averaging 95.1%. The blockchain storage overhead (BSO) displayed a near-linear growth pattern relative to the number of transactions, consistent with theoretical expectations for blockchain architectures. Reliability analysis indicated system uptime exceeding 95%, with only minimal operational failures recorded during the test period. This blockchain implementation further demonstrated reliable transaction processing and secure record management, indicating the effectiveness of the proposed Block-BVAS in enhancing the security, transparency, and trustworthiness of electronic voter accreditation.Item A framework for enabling data sharing and accessibility in a transdisciplinary federated marine spatial infrastructure(2026-08) Sibolla, Bolelang H; Molapo, Nkadimeng R; Vhengani, Lufuno M; Madanga, Diego; Maduenyane, GasethataThe Sustainable Development Goals and the United Nations Ocean Decade require preservation of the oceans and the efficient management of marine resources, contributing to sustainable use of oceans resources and the blue economy. Oceans span a wide area with exclusive economic zones of different countries adjacent to each other. This therefore necessitates the collaborative management of these resources across several countries in a region. Data is essential for providing trusted information, which in turn drives knowledge generation from science to policy implementation, towards informed decision making regarding the ocean resources. Harmonising data into decision support tools becomes a challenge due to two main reasons. Firstly, this is due to the transdisciplinary nature of the ocean, where data is governed by a variety of standards. Secondly, regional collaboration requires the data and knowledge to be shared in a federated environment in order to preserve data ownership by the custodians, while also cognisant of the network challenges in developing countries. This paper presents a standards compliant framework for enabling data sharing and access in these environments based on lessons learnt in the Marine and Coastal Operations for Southern Africa and Western Indian Ocean region, a project supported by the African Union Commission’s GMES and Africa program.Item Drug-resistant tuberculosis in rural Eastern Cape: Integrating whole-genome sequencing, conceptual transmission modelling and community-based participatory research(2026-09) Sineke, N; Faye, LM; Dlatu, N; Ombinda-Lemboumba, Saturnin; Apalata, TBackground: Drug-resistant tuberculosis (DR-TB) remains a major challenge in high-burden rural settings where biological, health-system, and social determinants interact. This study integrated whole-genome sequencing (WGS), mathematical modelling and Community-Based Participatory Research (CBPR)-informed principles to examine DR-TB within a conceptual biosocial framework. Methods: WGS data from 32 Mycobacterium tuberculosis isolates were analysed for resistance-associated mutations, phylogenetic lineages and genomic relatedness. A deterministic two-strain model explored drug-susceptible (DS) and DR-TB transmission. Hypothetical CBPR-informed scenarios modified transmission (β), treatment initiation (γ) and resistance amplification (α) parameters over 10 years. Results: Twenty-seven isolates (84.4%) showed resistance to at least one anti-TB drug, and 15 (46.9%) met MDR-TB criteria. Lineages 2 and 4 predominated. Under predefined assumptions, community-informed scenarios produced approximately 40–60% reductions in modelled DS-TB transmission and 20–35% reductions in DR-TB transmission relative to baseline. Conclusions: Integrating genomic evidence with transmission modelling and community-informed assumptions provides a useful hypothesis-generating framework for examining DR-TB. However, the modelled scenarios are exploratory and do not demonstrate the effectiveness of the CBPR intervention. Prospective studies using larger genomic datasets, longitudinal epidemiological data, and empirically measured community-level parameters are required.Item A socio-technical systems (STS) analysis of road fatalities in Gauteng province (2015-2019)(2026) Masuku, Freeman N; Sinclair, MRoad safety in Gauteng represents a persistent and complex socio-technical challenge, shaped by dynamic interactions between human factors, engineering design, institutional governance, and socio-economic contexts. This study employs a socio-technical systems (STS) framework to analyse the multifaceted contributors to road traffic fatalities in the province for 2015 to 2019; data from 2020 was excluded due to covid-19 mobility distortions that would have confounded analysis of underlying systemic risk factors. Utilising a mixed methods, convergent design, the research integrates qualitative institutional data with quantitative fatality and exposure metrics to model the interplay of social and technical subsystems. Key findings reveal that temporal variables (time of day, seasonal weather patterns), infrastructural and operational factors (road class, posted speed limits), and socio-economic pressures (unemployment rates, population density, GDP per capita) are interconnected within the STS and collectively exacerbate fatality risk. The Spatially Aware Poisson Random Forest (SAPRF) model achieved MAE ≈ 0.031, RMSE ≈ 0.109, and R² ≈ 0.958, substantially outperforming standard random forest (R² ≈ 0.872) and Poisson regression (R² ≈ 0.06). The novelty lies in the first application of SAPRF in a South African road safety context, integrating STS theory with spatially aware machine learning. The study concludes that prevailing behaviour-centric interventions are insufficient and argues for a paradigm shift toward integrated, multi-level policy and design interventions targeting the root systemic couplings and feedback mechanisms inherent in the road transport system.Item Urban planning to strengthen resilience to extreme climate events - a systematic review(2026-09) Birkmann, J; Rembold, M; Hampel, F; Mack, SL; Jamshed, A; Ehring, BD; Schick, D; Ramirez Herrera, AC; Thomae-Pohl, L; Pieterse, AmyA growing body of literature shows that cities are key actors in mitigation and adaptation to climate change. However, there is less knowledge about the approaches and challenges urban planners face in building resilience. Existing studies often focus on specific planning tools in selected cities, while limited attention is given to the wider assessment of challenges and tools used in different world regions and across income classes. This paper explores how urban planning-related challenges and measures for strengthening resilience vary across city sizes, regions, and income groups based on a systematic review of scientific papers applying the ROSES standards. The first analysis included 3410 articles, and following multiple screening iterations, 398 papers were ultimately considered for in-depth review. Data extraction was supported by LLM-based software, and the results were verified through in-person checking. We find that administrative issues (institutional fragmentation and lack of cooperation) are mentioned most frequently as a challenge across regions. In contrast, land-use conflicts differ significantly between world regions, though less so between cities of different size. Differences also emerge, e.g. in terms of the use of nature-based approaches (NbA) and digital tools. NbA are more frequently discussed in the literature that refers to small and very small cities compared to megacities and large cities. NbA are not solely common in Europe, but also in Africa and Small Island States. IT and digital tools are more frequently mentioned in papers that deal with cities in high-income countries. This digital divide points to the fact that the resources available to invest in such tools and technology also depend on income levels and financial resources. Overall, the findings underscore that multi-level governance and development conditions are important factors that influence the challenges faced by urban planning and its capacity to support resilience building.Item Bridging the in situ data gap: a satellite- and model-based framework for operational monitoring of marine harmful algal blooms and temperature-related threats in emerging economies(2026-09) Smith, Marie E; Bernard, S; Fearon, G; Krug, M; Molapo, Nkadimeng R; Veitch, J; Vhengani, Lufuno M; Williams, LEmerging and developing economies often face constrained financial, technical, and institutional capacities to establish and maintain the ocean-based in situ observational networks that underpin marine decision support applications. This limitation heightens their exposure and sensitivity to the cumulative impacts of marine environmental hazards, including harmful algal blooms and marine heatwaves. In this perspective, we present an example of an operational, co-developed ocean monitoring framework that is explicitly structured around user requirements, local scientific expertise, established software engineering practices, and openly available satellite and numerical model data and algorithms. The framework is instantiated through the South African National Oceans and Coastal Information Management System (OCIMS) Fisheries and Aquaculture Decision Support Tool, which is employed as a representative implementation case study and potential reference architecture for application in other regional contexts. We demonstrate that satellite-derived and model-based products can markedly accelerate the establishment of operational marine environmental monitoring capabilities in settings where dense, long-term in situ observing systems are absent or sparse, thereby enhancing societal preparedness and adaptive capacity in relation to intensifying, climate-driven marine risks. Furthermore, we discuss how such frameworks can underpin resilient, equitable, and evidence-based blue economy development in the Global South.Item Physical vertical fluxes decouple iron and manganese supply in the Southern Ocean(2026-05) Ramalepe, Thapelo; Roychoudhury, AN; Baudet, C; Bowie, A; Bucciarelli, E; Van Horsten, Natasha; Latour, P; Planquette, H; Sarthou, G; Sohrin, YSub-nanomolar concentrations of dissolved iron and manganese seasonally limit phytoplankton growth in the Southern Ocean, as both are essential cofactors for metabolic processes. These trace metals are supplied from the subsurface to the surface through physical processes, including winter entrainment, diapycnal diffusion and Ekman pumping, where they are made available for biological uptake. Whilst the quantification of these processes for iron has been previously reported, no large-scale quantification exists for manganese in the Southern Ocean. We analysed regridded dissolved iron and manganese data from all available Southern Ocean cruises, to quantify these physical supply processes. Here we show that winter entrainment (18.58 ± 4.82 μmol m⁻² yr⁻¹ manganese; 29.78 ± 5.23 μmol m⁻² yr⁻¹ iron), followed by diapycnal diffusion (1.59 ± 1.51 μmol m⁻² yr⁻¹ manganese; 0.55 ± 1.58 μmol m⁻² yr⁻¹ iron), dominates the supply across the Southern Ocean. Matched low iron: manganese supply ratios along the zero meridian and near the Antarctic Peninsula suggest potential iron–manganese co-limitation, with the latter consistent with field observations in the Drake Passage. Accurately reproducing this spatial variability in models will improve projections of trace metal control on the Southern Ocean carbon pump.Item Systematic Review: Governance mechanism in mitigating privacy breaches and restoring trust(2026-09) Mlambo, Tlangelani P; Zuva, TData breeches are eroding trust in institutions, despite regulations such as the “GDPR” and “POPIA”. Principles of governance, including accountability, transparencies and ethical leadership have been heralded as essential to prevent breaches and regain trust, although their specific contributions remain poorly understood. This research adopted a systematic review based on the PRISMA 2020 guidelines to explore peer-reviewed literature published between 2020 and 2025. The review consisted of reports sourced from Google Scholar, IEEE, Springer and Sage that covered governance into privacy and security and comprehensive service provision. Only peer reviewed articles in the English language were included, and technical only papers were excluded. The review looked at governance methods, breach situations, trust-building strategies, and differences between regions, with quality checked using CASP and AMSTAR 2 tools. Results show that flexible governance frameworks that use privacy-by-design, involve stakeholders, and include ESG principles are most effective for reducing breaches and restoring trust. The review suggests that governance should go beyond just following rules and should include ethical leadership and adaptable methods to strengthen institutions and support responsible digital change. The study reviewed 100 articles from 2020 to 2025 and selected 25 for detailed analysis across different industries. Future research could look at articles beyond 2025 and examine which governance factors are most often studied.Item Hybrid-additive manufacturing cost model: A sustainable through-life engineering support for maintenance repair overhaul in the aerospace(2020) Oyesola, MO; Mpofu, K; Mathe, Ntombizodwa R; Daniyan, IAThe drive for a more flexible Through-life Engineering servicing technology that can enhance both productivity and profitability for the operation of maintenance, repair, overhaul (MRO) in the aerospace implores harnessing the innovation of hybrid-additive manufacturing (HAM). Hybrid manufacturing system seeks to reduce cost by utilizing the tool-less production principle of additive manufacturing combine with the conventional subtractive manufacturing for product finishing or post-processing. HAM has many merits that make it an attractive option in manufacturing of high performance products as peculiar to MRO businesses. Therefore, this paper aims to establish a cost model derived from a “Time Driven Activity Based Costing” approach for the technological integration of Hybrid system to increase economic competitiveness of highly MRO services in the aerospace industry. Hence, a unique cost formulation method was investigated through analytical technique in cost engineering models for the purpose of manufacturing processes.Item In vitro antioxidant and anti-inflammatory effects of plantago major, cannabis sativa and ranunculus multifidus on LPS-stimulated raw 264.7 macrophages(2026-10) Nxumalo, Precious Z; Gom, Buntubonke; Masuku, N; Theron, Anjo; Mokoka, T; Bareetseng, Andries; McGaw, LChronic inflammation is a major contributor to cancer progression, driven by persistent pro-inflammatory signalling and oxidative stress. Plant-derived bioactive compounds offer therapeutic potential by modulating these pathways. This study evaluated the antioxidant and anti-inflammatory effects of leaf extracts from Cannabis sativa L., Plantago major L., and Ranunculus multifidus Forssk. in LPS-stimulated RAW 264.7 macrophages. Extracts were tested for cytotoxicity (MTT assay), nitric oxide (NO) inhibition (Griess assay), cytokine modulation (ELISA), antioxidant activity (DPPH and ABTS assays), and 15-lipoxygenase (15-LOX) inhibition. UPLC-MS analysis was used to identify potential phytochemical constituents. All extracts were non-cytotoxic at 5 - 15 µg/mL concentrations. The extract from R. multifidus had the highest NO inhibition (20%), followed by P. major (17%), while C. sativa exhibited no significant effect. The ELISA assay revealed extract-specific cytokine modulation. P. major strongly suppressed IL-6 and IL-1β and enhanced IL-10 secretion, while C. sativa inhibited IL-6, PTGS2 and moderately reduced iNOS. In contrast, R. multifidus showed variable effects and did not inhibit iNOS and IL-1β. However, it induced variable effects on IL-6 inhibition and IL-10 secretion. The antioxidant assays revealed potent radical scavenging: C. sativa achieved 92.5% DPPH scavenging comparable to ascorbic acid, while ABTS scavenging exceeded 90% for P. major and R. multifidus, closely matching Trolox. All extracts inhibited 15-LOX, with C. sativa showing the highest inhibition (96.2%). UPLC-MS identified the presence of cannabigerolic acid (CBGA) and Δ⁹-THC in C. sativa and verbascoside in P. major, while no major compounds were conclusively identified in R. multifidus. These findings provide the first evidence of cytokine modulation and anti-inflammatory activity by R. multifidus. Moreover, they highlight the complementary antioxidant and anti-inflammatory potential of C. sativa and P. major, supported by phytochemical evidence. These extracts represent promising natural immunomodulatory agents.Item Wear characteristics of laser-deposited AlCoCrCuFeNi high entropy alloy with finite element analysis(2022-11) Dada, M; Popoola, P; Mathe, Ntombizodwa R; Adeosun, SWear is a destructive phenomenon and one of the principal causes of material failure in moving components during surface interaction while in service. AlCoCrCuFeNi high-entropy alloy with its many properties is a potential material for aero-engine applications attributed to its outstanding relatively lightweight, high strength, good thermal, oxidation, and corrosion resistance properties. Hence, the investigation into the tribological behaviour of AlCoCrCuFeNi high-entropy alloys is essential to reduce maintenance costs and prolong the service life of this advanced material for aerospace applications. Most AlCoCrCuFeNi high-entropy alloy compositions were fabricated via arc melting, which has been reported to have defects attributed to slow solidification, consequently reducing the mechanical properties of the alloy with limited reports on other fabrication methods. Therefore, there is a need for the use of advanced manufacturing techniques for fabricating these alloys to improve the tribological properties. In this study, AlCoCrCuFeNi high-entropy alloy was fabricated via laser metal deposition. The influence of the laser processing parameters, rapid solidification, and the applied load on the tribological properties of the as-built alloys under dry conditions has been studied for aerospace applications. The counter ball rolling friction analysis was also investigated using COMSOL Multiphysics.Item High-temperature corrosion of Ti6Al4V and in-situ reinforced composites fabricated by laser additive manufacturing(2026-09) Kgomo, Matsela TH; Masina, Bathusile N; Mathoho, Ipfi; Mulaudzi, VThis study investigates the high-temperature corrosion behaviour of directed energy deposited (DED) Ti6Al4V (Ti64) and its in-situ composites (TiC/Ti64 and TiBw/Ti64) in oxygen-rich NaCl- Na2SO4 environments at 300 °C, 600 °C, and 900 °C. DED produces refined microstructures with reinforcement phases distributed along grain boundaries, fundamentally altering corrosion mechanisms. Thermogravimetric analysis revealed that TiBw/Ti64 exhibited superior resistance (activation energy: 282 kJ/mol) due to the formation of stable boron oxides (B2O3) that maintained protective layer integrity through self-healing mechanisms. TiC/Ti64 showed intermediate performance (276 kJ/mol), with TiC particles acting as oxygen diffusion barriers but undergoing oxidation at > 800 °C to form TiO2 and carbon residues. Unreinforced Ti64 suffered severe material loss (198 kJ/mol) via volatile TiCl4 formation that disrupted the oxide scale. Microstructural analysis demonstrated that AM-induced grain refinement enhanced oxide nucleation site density, while reinforcement distribution influenced galvanic interactions. These findings establish that in- situ TiBw/Ti64 fabricated by DED offers optimal performance for aerospace and marine. applications below 600 °C, with degradation mechanisms transitioning from surface oxidation to bulk volatilization above this threshold.Item Insights from ‘Unlocking COVID-19 current realities, future opportunities: Artificial intelligence in the time of COVID-19’(2021-03) Mathe, Ntombizodwa RThe University of Cape Town, in partnership with Standard Bank, hosted a webinar entitled ‘Unlocking COVID-19 current realities, future opportunities: Artificial intelligence in the time of COVID-19’ on 19 August 2020. The webinar was facilitated by Professor Tommie Meyer from the University of Cape Town’s Centre of Artificial Intelligence Research at the Department of Computer Science. The two speakers for the event were Professor Tshilidzi Marwala, Vice Chancellor and Principal of the University of Johannesburg and a pioneer in the field of artificial intelligence (AI) in South Africa and the Deputy Chair of the Presidential Commission on the Fourth Industrial Revolution (4IR). The second speaker was Mr Nanda Padayachee, Head AI, Automation and APIs at the Standard Bank Group. He has extensive experience in digitisation of capabilities and established the Inaugural Data Science capabilities within the Standard Bank Group.Item Terrain-aware head gesture recognition for turret control using helmet-mounted IMUs and vehicle vibration fusion(2026-09) Rooibaard, Lonwabo; Modungwa, Dithoto M; Sibiya, M; Pandelani, THead gesture-based control using inertial measurement units (IMUs) provides an intuitive alternative to conventional human–machine interfaces for mobile and vehicle-mounted systems. However, gesture recognition reliability degrades significantly under terrain-induced vibration and mechanically dynamic operating conditions. This study investigates terrain-aware head gesture recognition through the integration of helmet-mounted IMU measurements and vehicle vibration sensing to improve discrimination between intentional gestures and non-intentional motion artefacts. Vehicle vibration data were collected from a patrol vehicle traversing the Ndumo Border Patrol route, characterised by variable terrain roughness and dynamic excitation profiles. Triaxial seat-rack acceleration data were acquired at 10 kHz, anti-alias filtered and down sampled to 100 Hz before being integrated with IMU-derived head motion measurements using both vibration-aware data augmentation and early sensor fusion strategies. FFT-based spectral processing and classification using a lightweight fully connected neural network (FCNN) were implemented using the Edge Impulse framework. Experimental evaluation was performed using temporally independent training and testing segments to reduce overlap leakage and ensure realistic generalisation assessment. Results demonstrate that terrain-informed sensing substantially improves operational robustness under mobile conditions. The early-fusion approach achieved 98.45% independent-test accuracy under float32 inference and maintained 90.02% accuracy after int8 quantization, corresponding to an accuracy reduction of 8.43 percentage points. In comparison, the Clean IMU and vibration-augmented models exhibited reductions of 20.13 and 27.02 percentage points, respectively, demonstrating greater sensitivity to quantization. The evaluated models also exhibited low inference latency and compact memory requirements, supporting their suitability for real-time edge implementation. These findings demonstrate that treating terrain vibration as contextual information, rather than solely as environmental noise, can improve the quantization robustness and deployment characteristics of IMU-based gesture-recognition systems intended for mechanically dynamic platforms.Item In-situ reactive synthesis and characterization of a high entropy alloy coating by laser metal deposition(2022-03) Dada, M; Popoola, P; Mathe, Ntombizodwa R; Pityana, Sisa L; Adeosun, SIn this study, we investigate the influence of in situ reactive synthesis of Ti6Al4V– AlCoCrFeNiCu high entropy alloys by laser metal deposition on the microstructural and mechanical properties of the as-built alloy as opposed to the traditional method of mixing powders via a ball mill prone to contamination and segregation. We explore the capability of a new alloy design by combining two base alloys via in situ reactive alloying, delivering the Ti6Al4V and AlCoCrFeNiCu high entropy alloy powders from multiple powder feeders and regulating their feed rate ratios. The nano mechanical, tribological and microstructural morphologies of the alloys were characterized using a nanoindentation tester, a tribometer, XRD and SEM, respectively. The results showed that satelliting the high entropy alloys powder and the Ti6Al4V powder fraction using double powder feedstock had a homogeneous distribution with dendritic structures. Optimization was achieved at a laser power of 1600 W, a scan speed of 12 mm/s and a powder flow rate of 2 g/min. The surface roughness (Ra) for Ti–6Al–4V, AlCoCrCuFeNi and (Ti–6Al–4V)-(AlCoCrCuFeNi) alloy was 0.5 μm, 0.63 μm and 0.80 μm, respectively. The high wear resistance of the novel Ti6Al4V– AlCoCrFeNiCu alloy was influenced by the hardness of the alloy which was higher than the Ti6Al4V alloy and the AlCoCrFeNiCu alloy. This study successfully defines the capabilities of in situ fabrication of high entropy alloys and presents novel techniques for multiple powder preparation of high entropy alloys using laser additive manufacturing, to permit the next generation of compositionally graded materials for aerospace components.Item Optimization of selective laser melting process parameters for surface quality performance of the fabricated Ti6Al4V(2021-03) Oyesola, M; Mpofu, K; Mathe, Ntombizodwa R; Fatoba, S; Hoosain, Shaik E; Daniyan, DThe purpose of this study is to study the influence of the laser power and the scanning speed on the surface hardness, and top surface and side surface roughness of Ti6Al4V metal specimens fabricated via the selective laser melting (SLM) technique. The laser power was varied between 150 and 300 W while the scan speed was varied between 800 and 1400 mm/s. Response surface methodology (RSM) in the Design Expert 11 software environment was used for the design of experiment and results analysis. The distance for surface indentations were targeted at 10–20 μm for the top surface and 60–80 μm for the side surface while the surface hardness profiling was studied using an indenter with the indentation performed at a load of 500 gf and at a dwelling time of 15 s. The study revealed that as the laser power was increased, the surface hardness increases, while the top surface and side surface roughness reduces. Then, when the scanning speed increased, the surface hardness, and top surface and side surface roughness were found to also increase. The optimum range of the process parameters selected are laser speed 300 W and scan speed 1400 mm/s. This produces a minimum surface roughness of 13.006 μm for the top surface roughness and 62.166 μm for the side surface roughness with a corresponding hardness value of 409.391 HV. The findings of this study will assist manufacturers in the process design of the SLM of titanium alloy for aerospace applications.Item A review and synthesis of the Consultative Group on International Agricultural Research’s work on climate-induced extreme rainfall and floods, 2012–2023(2026-09) Chikozho, C; Mukherji, A; Bosire, C; Kujinga, K; Managa, Lavhelesani RIn recent decades, the increased frequency of extreme rainfall events has significantly affected agri-food systems, accounting for 19% of the total crop damage across the world and 18–43% of observed anomalies in global crop yields. Some studies indicate a global weighted mean rice yield loss of 9.0% by 2080 under a high-emissions scenario. In sub-Saharan Africa, crop yield losses from extreme rainfall can vary significantly, with one source citing a 33% reduction over the past 60 years due to climate-induced weather extremes, including floods. It is estimated that in Africa, about 12% of the people that experienced food insecurity from 2009 to 2020 had their food security status affected by flooding. The Sixth IPCC assessment report warns that climate change could push an additional 32–132 million people into extreme poverty by 2030 if the world does not immediately scale up adaptation solutions. This review articulates the CGIAR’s contribution to scientific knowledge on climate-induced extreme rainfall for the period 2012–2023. The review discusses research methods applied, main impacts of extreme rainfall on agri-food systems, and innovative adaptation solutions deployed. Out of 2846 identified papers, 73 studies met our search criteria and were included in the review. Our analysis reveals that the main impacts of extreme rainfall addressed by the CGIAR include physical loss of crops due to coastal area inundation, waterlogging, and salinity intrusion. Adaptation options that build the resilience of smallholder farming systems include scientific methods for forecasting changes in rainfall patterns; flood early warning systems; climate-smart agricultural technologies; flood-resilient seed varieties; and agroforestry. However, lack of finance and knowledge tends to limit smallholder farmers’ ability to adopt some of the technological innovations, suggesting the need for capacity building and policies for better access to microcredit, low-interest loans, and climate risk insurance schemes. Research gaps identified in the study call for the CGIAR to also focus on currently underexplored themes such as roots and tubers, livestock, fish, and peri-urban agriculture. The integration of attribution studies that address direct links between extreme rainfall and climate change could inform targeted interventions arising from CGIAR research. Studies that specifically quantify economic losses from floods could also generate important insights for effective agricultural investment and risk management. This review identifies key areas of focus and critical knowledge gaps to be addressed by future CGIAR research. It informs the agenda of decision makers and policy makers who grapple with the challenges of scaling adaptation solutions to strengthen farmers’ resilience to extreme rainfall.Item Bioinspired electrospun chitosan–based materials for tissue regeneration(2026-06) Mokhena, TC; Mtibe, Asanda; Hlekelele, Lerato; Nhlapo, A; Shingange, K; Mapukata, S; Mapossa, AB; Mochane, MJ; Mathete, E; Shumbula, N; Ntwaeaborwa, OMChitosan (CS) is a cationic biopolymer that has shown unique opportunities in tissue engineering. The well-defined geometry, porosity, easy processability, and antimicrobial and antifungal properties are particularly beneficial for tissue regeneration. This review outlines the progress made in the preparation of bioinspired electrospun CS for tissue regeneration. The article concentrates on bioinspired electrospun CS and CS-based composites which have appeared in a good number of publications in the literature and enriched the field of tissue engineering. It also highlights the upscaling of electrospun nanofibers with recent advanced technologies. Finally, the overall summary, challenges, and future perspective in tissue regeneration based on bioinspired CS and related composite materials is presented.Item Functionalized bio-based materials for water treatment: Advances in cellulose, lignin, melanin, and hybrid systems(2026-10) Paolino, F; Mtibe, Asanda; Nomadolo, Elizabeth E; D'Orsi, R; Lucejko, JJ; Operamolla, A; Maya, Mathew JAccess to safe drinking water remains a global challenge due to increasing contamination by heavy metals, organic pollutants, dyes, pharmaceuticals, oils, and pathogenic microorganisms. In this context, sustainable and low-impact materials for water purification are gaining increasing attention. This review focuses on bio-based materials, specifically cellulose, lignin, and melanin, as well as their functionalized derivatives and hybrid systems, for water purification applications. These materials are integrated within a common framework, allowing direct comparison of their structure–property–performance relationships and highlighting potential complementary functionalities. Emphasis is placed on adsorption–filtration processes, membrane technologies, and electrospun fibrous systems. Nanocellulose-based materials, including cellulose nanocrystals, nanofibers, and bacterial cellulose, are discussed in terms of extraction methods, surface functionalization, adsorption behavior, and performance toward a wide range of contaminants. Lignin-based systems, such as sorbents, hydrogels, foams, aerogels, and hybrid membranes, are examined with attention to the effects of chemical modification on adsorption capacity, selectivity, and reusability. Emerging melanin and melanin-like materials, particularly polydopamine-based systems, are also considered, highlighting their ability to bind metal ions and organic pollutants and their integration into multifunctional composites and membranes. Across all material classes, the role of surface chemistry, porosity, and structural organization in determining adsorption performance is discussed, together with adsorption models, regeneration behavior, practical constraints, and the current level of technological maturity of the different material systems. After an overview of biodegradability and sustainability aspects, the review critically examines key limitations, including long-term stability, regeneration efficiency, validation under realistic wastewater conditions, and scalability, which currently hinder large-scale implementation. These aspects are discussed to outline future research directions toward the development of effective and sustainable water purification technologies based on renewable bio-based materials.