Faculty of Science, Engineering and Agriculture

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Open Access
3D Cranial Morphometry, Sensory Ecology and Climate Change in African Rodents
(2019-05-15) Nengovhela, Aluwani; Taylor,, Peter; Braga, Jose
The order Rodentia is the most speciose group of mammals with muroids being the most diverse superfamily. Since they are represented in arboreal, semiaquatic, subterranean and terrestrial niches, rodents may exhibit morphological traits reflecting their adaptations to such diverse environments. This thesis focuses on the morphology of the endocranium, auditory bulla and cochlea in three tribes (Otomyini, Taterillini and Gerbillini) representing 10 species of African rodents, concentrating on their variability, function and adaptability, using micro-CT imaging and 3D shape comparative methods. Additionally, variations in cranial size were also studied in respective of global warming and climatic variables. Morphological changes/variations are a result of environmental change, therefore each chapter in this study details the effect of environmental change (in space and time) on different morphological traits i.e. general cranial size (chapter 2), cochlea and auditory bulla (chapter 3) and endocranial size and shape (chapter 4). With chapter 2 dealing specifically with climate change in its strict sense and the remaining two chapters looking at different environmental gradients. Chapter 2 tests the applicability of the “third universal response to warming” (i.e. declining body size) and the Resource Rule in two murid subfamilies, Murinae and Gerbillinae. The study shows that the third response is not as universal as only one species conformed to this response. Further, food availability (Resource Rule) was shown to be the more important factor correlated with body size variations in rodent species than Bergmann’s Rule. Chapter 3 looks at the auditory bulla and cochlea, the morphological traits that play a role in hearing capabilities of rodents. I found, with some exceptions, that bulla and cochlea modifications between species could be explained by environment, phylogeny and/or allometry. In addition, I concluded that true desert adapted laminate-toothed rats and gerbils use both bulla and associated cochlea hypertrophy. Chapter 4 shows larger brain size in Taterillini and two species of Otomyini, with life histories and environment being the most probably factors responsible for xiv this. Using a novel method of diffeomorphism (deformation models), there was more variation in endocranial morphology between the gerbils and laminate-toothed rats than within them with olfactory bulb, paraflocculi, and posterior ventral cortex showing the most variability. Overall, this thesis shows that variations in the morphological traits studied are strongly influenced by the environment and function.
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A Comparative Analysis of Machine Learning Models and Traditional Statistical Models for Continuous-Time Survival Analysis
(2026-05-19) Tshisikule, Ompha; Mulaudzi, T. B.; Bere, A.
Survival analysis is a statistical technique used to model time-to-event data, commonly applied in fields such as healthcare, engineering, and finance. Traditional approaches, including the Cox Proportional Hazards (CoxPH) model, have long been dominant due to their interpretability and theoretical foundation. However, recent advances in machine learning have shown promise in handling complex, high-dimensional datasets with nonlinear relationships. Despite this, there remains a gap in systematic comparative studies between traditional survival models and modern approaches such as regularized regression, ensemble methods, and deep learning architectures, particularly across diverse datasets with varying characteristics. This study conducts a comparative analysis of traditional, machine learning, and deep learning-based survival models, evaluating their predictive performance and computational efficiency for continuous-time survival data. The models considered include LASSO-regularized Cox regression, CoxPH, Random Survival Forest (RSF), and Long Short-Term Memory (LSTM) algorithms. Model performance was assessed using the concordance index (C-index), integrated Brier score (IBS), and Time-dependent Area Under the Curve (AUC) across three secondary datasets with different characteristics: a breast cancer dataset obtained from the SEER Program of the National Cancer Institute (2017 November update), the North Carolina Recidivism dataset (ICPSR 8987) obtained from ICPSR, and a heart failure clinical records dataset obtained from Kaggle. A rigorous statistical framework was employed, utilizing 100 iterations of stratified train-test splits to generate robust performance distributions. Distributional assumptions were systematically tested using Shapiro-Wilk and Levene’s tests to determine appropriate statistical tests, followed by omnibus tests (ANOVA, Welch’s ANOVA, or Kruskal-Wallis) and post-hoc pairwise comparisons with Bonferroni correction to control family-wise error rates. The analysis revealed that traditional survival models consistently outperformed deep learning-based approaches across all datasets. Random Survival Forest achieved the highest predictive accuracy, followed closely by CoxPH, with C-index values ranging from 0.66 to 0.73 and lower IBS scores indicating better calibration. In contrast, LSTM models performed poorly, often near random prediction levels (C-index 0.3–0.42), despite extensive optimization efforts including hyperparameter tuning, class balancing, and architectural modifications. Statistical testing confirmed that performance differences were highly significant across models and datasets (all p < 0.001), and post-hoc analyses demonstrated that RSF and CoxPH consistently outperformed LSTM for both discrimination and calibration metrics. These results suggest that traditional survival models remain the most reliable choice for moderate-sized datasets with censored observations and weak predictive signals, while LSTM networks are limited by dataset size, high censoring, and architectural mismatch with static survival data.
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A comparative analysis of perceptions on land expropration by commercial and emerging farmers in Limpopo Province of South Africa
(2026-05-19) Ngoepe, Hunadi Annah; Chauke, P. K.
The land reform programme has been very slow in achieving its goal. The slow process of the land reform program has led to the initiation of the Land expropriation in line with Section 25 of the South African Constitution. The purpose of the Land Expropriation Act is to expedite the process of giving back the land to the rightful owners, taking note that most of the current landowners have secured loans with the financial institutions. This study seeks to find out how commercial farmers and emerging farmers perceive land expropriation. The study was conducted in five districts of the Limpopo province of South Africa. A simple random sampling technique was used to select 150 participants from a population of 230 farmers. The study made use of structured interviews where questionnaires were used as a primary tool to collect data. Descriptive statistic was used to determine socio-economic characteristics. The study revealed that males dominated the farming industry, with males outnumbering females, particularly among emerging farmers. Likert scale and ordinal logistic regression were used to analyse the data. Emerging farmers expressed the view that land should be expropriated. However, commercial farmers indicated that land should not be expropriated as this would lead to increased poverty and unemployment. Inferential statistical results revealed that race is a key socio-economic factor driving differences in perception about land expropriation. Bank officials agreed that land expropriation would have negative implications on interest rates, leading to a decline in the country’s GDP. Policy implementors should consider the concerns of commercial farmers and banking officials regarding the Land Expropriation Act, which may have significant economic implications. Additionally, they should account the socio-economic characteristics that strongly influence farmers' perceptions of land expropriation.
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A comparative evaluation of machine learning models for stock price prediction and uncertainity estimation
(2026-05-19) Nengovhela, Vhukhudo; Ravele, T.; Sigauke, C.; Ndogmo, J. C.
This study compares machine learning models for stock price prediction and uncertainty estimation using high-frequency one-minute stock data. The research looks at how different models perform across developed and emerging markets, which helps with model selection for practical financial forecasting. Four models were tested for point forecasting: Random Forest (RF), Gradient Boosting (GB), Multi-Layer Perceptron (MLP), and a hybrid stacking ensemble composed of multiple base learners. For uncertainty quantification, three interval prediction methods were used: Bootstrap Residuals, Quantile Regression Forests (QRF), and Conformalised Quantile Regression (CQR). The analysis used one-minute stock price data from Microsoft Corporation (MSFT) as a developed market example and Standard Bank Group (SBK.JO) as an emerging market example, covering the period from 3rd to 26th September 2025. The results show that GB performed best for point forecasts in both markets. For MSFT, GB had RMSE of 0.2875 and MAE of 0.1869, while for SBK.JO it achieved RMSE of 25.9248 and MAE of 14.3638. Statistical tests using the Diebold-Mariano and Giacomini-White frameworks confirmed that GB significantly outperformed the other models. For interval prediction, QRF gave sharper intervals in the relatively stable developed market, while CQR achieved better coverage in the more volatile emerging market. The Hybrid Stacking model showed some advantages in volatile conditions but didn’t consistently beat well-tuned individual models. These findings suggest that ensemble methods like GB are still very effective for financial forecasting, and that uncertainty quantification methods should be chosen based on market volatility. The study provides practical guidance for selecting forecasting methods depending on market conditions and data characteristics, which should help both researchers and practitioners working in financial risk management.
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A Comparative Study on the Efficacy of Modified Clay Soil for the Decolouration of Acidic and Basic Textile Dyes: A Case Study
(2025-09-05) Chauke, Livingstone; Gumbo, J. R.; Ngulube, T.
Dyes play a crucial role in the production of various products, including paper, plastics, and leather. However, their release into the environment leads to pollution and poses health risks to both humans and animals. Therefore, it is essential to treat dye-containing effluents before they are discharged into the environment. This study employed a cost-effective method to remove dyes from wastewater by utilizing natural clay as an adsorbent. The efficacy of Mn²⁺/Al³⁺ oxide-modified Mukondeni black clay soil (smectite) in removing acidic (Methyl Orange, MO) and basic (Crystal Violet, CV) textile dyes was evaluated. A 1:3 modified smectite ratio was identified as the most effective adsorbent. Characterization using X-ray Fluorescence (XRF), Brunauer-Emmet-Teller (BET), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared (FTIR), and Point of Zero Charge (PZC) revealed that Modified-SMT contained 18.42% Al₂O₃ and 61.08% SiO₂, had a surface area of 35.30 m²/g, and featured functional groups such as C–O, C–O–C, and O–H, with a PZC at pH 4.30. Maximum dye removal efficiencies were recorded at 91.95% for MO after 90 min under the conditions (initial dye concentration = 20 mg/L, temperature = 30 °C, contact time = 90 minutes, shaking speed = 250 rpm, solution volume = 30 mL, and an adsorbent mass = 2 g). For CV, an efficiency of 96.35% was achieved after 30 minutes under conditions (initial dye concentration = 20 mg/L, temperature = 30 °C, contact time = 30 minutes, shaking speed = 250 rpm, solution volume = 30 mL, and an adsorbent mass = 0.1 g). Adsorption isotherm analysis indicated that MO followed a multilayer mechanism on heterogeneous surfaces (Freundlich model), while CV exhibited monolayer adsorption on homogeneous surfaces (Langmuir model). Kinetic studies confirmed pseudo-second-order behaviour. Thermodynamic parameters Δ𝐻 = - 47.72 KJ/mol and Δ𝑆 = -0.17 J/mol/K showed that MO adsorption was non-spontaneous and exothermic (ΔG = 12. 64 KJ/mol for 80 °C), whereas Δ𝐻 = 22.64 KJ/mol and Δ𝑆 = 0.09 J/mol/K for CV adsorption was spontaneous and endothermic (ΔG = -9.55 KJ/mol for 80 °C). The adsorbent retained its efficiency over four regeneration cycles, demonstrating its suitability as a sustainable and effective solution for dye removal in wastewater treatment. It can be concluded that Mn²⁺/Al³⁺ oxide-modified Mukondeni black clay soil (smectite) can remove both MO and CV dye from aqueous solution.
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A framework for faciltating implementation of biogas technology in rural areas of South Africa
(2026-05-19) Rasimphi, Thilivhali Eugene; Tinarwo, David; Nyamukondiwa, Pertina
Access to reliable and clean energy remains a challenge in rural South Africa, where many households continue to depend on firewood and other traditional fuels. Although biogas technology has been introduced in several communities, its uptake remains limited. This has direct implications for rural development because unsuccessful energy initiatives weaken community trust, limit sustainability, and discourage future investment in local technologies. This study examined the factors that influence biogas adoption in rural Limpopo and developed a framework to guide successful implementation in line with rural development priorities. It explored barriers and opportunities, assessed household and stakeholder perceptions, and identified strategies for integrating biogas into rural economic and social systems. A qualitative research design was used, guided by grounded theory and the Systems Thinking Framework. Data was purposively collected from households, schools, and key stakeholders through observations and semi-structured interviews. Thematic content analysis, supported by NVivo and Atlas.ti 12.0, helped identify recurring patterns, systemic constraints, and feedback loops that shape adoption. Findings showed that socio-cultural beliefs, such as taboos around waste handling, along with low awareness of biogas benefits, limited uptake. Technical challenges, including poor maintenance skills and limited access to trained personnel, further restricted adaptability. Financial barriers, such as high upfront costs and constrained access to credit, also affected household investment decisions. Enabling factors included community participation in decision-making, cost-sharing, and municipal involvement in planning and policy alignment. The study found that successful biogas implementation requires participatory approaches that align with core rural development principles. The proposed framework highlights capacity building, community-based financing, and stronger links with agricultural activities to support productive use. By integrating social, economic, and environmental dimensions, the framework contributes to improved livelihoods, clean energy access, and greater resilience in rural communities. The study advances knowledge by applying systems thinking to renewable energy adoption and offers practical guidance for policymakers, funders, and practitioners. It also supports the Integrated Rural Development Sector Strategy (DALRRD, 2023) and Sustainable Development Goals (SDGs) by promoting sustainable livelihoods, poverty reduction, and social inclusion in rural South Africa.
Open Access
A learning domain-based training approach for smallholder irrigated maize farming in Mashonaland Central Province of Zimbabwe
(2025-05-16) Binala, Livinia; Francis, J.; Mupetesi, T.
The study was carried out to investigate the effectiveness of training approaches for smallholder irrigated maize farmers in Zimbabwe, particularly their crucial role in national food security and rural livelihoods. Despite irrigation's potential to boost productivity of maize, many farmers encountered challenges in adopting improved practices partly due to inadequate training methods. Thus, the study sought to evaluate current training frameworks and propose a comprehensive model integrating Bloom's taxonomy of learning domains to enhance knowledge acquisition and practical skills among farmers. The objectives of the study were 1) to identify the key learning domains for effective use of irrigation technologies in smallholder maize farming in Mashonaland Central Province 2) to propose a training approach that is tailored to the identified learning domains and the specific needs and constraints of smallholder farmers in Mashonaland Central; 3) to evaluate the effectiveness of the developed training approach on the productivity and income of smallholder maize farmers in Mashonaland Central Province; and 4) to assess the effectiveness of the developed training approach in improving the knowledge and skills of smallholder farmers in the use of irrigation technologies for maize farming. Three irrigation schemes that focused on maize production and located in two natural regions, that is, II and IV within Mashonaland Central Province were purposively selected. Proximity to the Harare, the capital city or extent of the scheme’s rurality was considered. The census method of data collection was applied. All the 472 farmers involved in irrigation in the three schemes were earmarked for the questionnaire-based survey. Employing a mixed-methods approach, the study combined quantitative surveys and qualitative interviews with farmers and agricultural extension officers across the three irrigation schemes. Key findings indicated that Farmer Field Schools (FFS) significantly outperformed traditional Master Farmer Training (MFT) in promoting effective learning and adoption of sustainable practices (P < 0.05). The study underscored the importance of participatory training methods, which resonate more effectively with farmers' needs and educational backgrounds. Using the results of the study, a framework that includes the following as the key components was proposed: a) Incorporation of cognitive, affective, and psychomotor learning domains b) Prioritization of hands-on training with visual aids c) Promotion of sustainable farming practices d) Strengthening of farmer-extension linkages e) Investment in teaching materials and monitoring mechanisms This study advocated for a paradigm shift in agricultural training methodologies. Adopting the recommended framework would enable policymakers and practitioners to significantly enhance the productivity and livelihoods of smallholder maize farmers, thereby contributing to improved food security. Furthermore, the study highlighted the need for deploying participatory and practical training, addressing key skills gaps, in addition to developing robust farmer-extension relationships to achieve these goals. Integration of Bloom's learning domains into farmer training curricula is a strategic roadmap for designing more effective and impactful training of smallholder irrigated maize farmers.
Open Access
A metagenomic snapshot of selected wastewater treatment plants in Vhembe Region, Limpopo, South Africa: Investigating the resistome
(2024-09-06) Jacobs, Damien; Potgieter, N.; Traore, A. N.
Background: Water is crucial for human life. Rural communities often rely on natural water sources which may become polluted by wastewater due to various activities such as domestic use and agriculture. Antibiotic resistance genes (ARGs) may be transferred from wastewater to the environment and pose a global challenge they affect both human and animal-related sectors. Studying antibiotic resistance in wastewater treatment plants within Vhembe offers a representation of antibiotic resistance genes from entire communities. Knowledge of antibiotic resistance circulating in Vhembe has been sparsely studied. Metagenomics approaches allow for a broad overview of the resistome and the bacterial communities within environmental samples. Aim: To perform wastewater surveillance of antibiotic resistance genes and associated bacteria within Vhembe, Limpopo, South Africa, using a metagenomics approach. Method: A total of 32 sample duplicates were collected from the influents (n=18) and the effluents (n = 14) from nine wastewater treatment plants (WWTPs) around the Vhembe region, Limpopo, South Africa. One hundred milliliter was filtered using sterile cotton gauze and Wattman filter paper to remove debris and membrane filtered through 0.22um membrane filters to capture the bacteria within each sample. DNA was extracted directly from the 0.22 μm filters using a DNA miniprep kit. DNA was quantified using a spectrophotometer. Shotgun 18 metagenomic sequencing was performed on DNA extracts. Open-source bioinformatics pipelines were used to process and analyze raw sequence data, uncovering information of the bacterial community composition and associated ARGs in wastewater. Results: Site observations reveal animal and human activities within and near the sites. ARG analysis revealed an overall number 0f 220 ARGs detected across the WWTPs. Thirty-six genes were common to influent samples and 16 in within effluent samples, encoding predominantly against macrolides, sulfonamides and tetracyclines, beta-lactamases, and aminoglycosides. Some unique ARGS were detected at sites near South African borders. Bacterial Diversity showed the predominance of some genera, such as Arcobacter, Aeromonas, Pseudomonas and Acinetobacter. Pathogens were predominantly enteric and pulmonary, with some being linked to animals in past studies. A notable increase in some members of Mycobactericeae, among other bacteria, was noted in effluents.
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A Multi-level Model for a Vector-Borne Organ to Tissue life Cycle Dynamics
(2025-09-05) Mahada, Awelani Sydney; Netshikweta, R.; Garira, W.
Introduction: Malaria is among the World’s most lethal infectious disease. It is caused by a parasitic pathogen transmitted by the Anopheles mosquito, which inoculates sporozoites into the human host during a blood meal. The population dynamics of malaria are well-known for their complexity, stemming not only from the parasite’s lifecycle, which involves two hosts (humans and mosquitoes)but also from the intricate replication and transmission cycles across different levels of the infectious disease system organization. Like other infectious disease systems, malaria infections inherit multilevel and multiscale systems, which pose significant challenges to efforts aimed at eliminating and ultimately eradicating the infection in a malaria-endemic population. Methodology Mathematical modeling in the study of complex system has proven to be an invaluable tool for understanding and predicting the behaviour and dynamics of a complex system within the domain of complexity science. Thus, in this study, we propose a multiscale modelling framework that captures the dynamics of malaria across three organizational levels within infectious disease systems implicated in the spread of malaria in a community. We begin by formulating a mathematical model to describe the development and progression of malaria parasites within the liver and tissue(blood) stages of an infected human host. This is followed by the formulation of a multiscale model that integrates both the inside(i.e.,the organ-tissue level)host and the outside (i.e., the host level) host malaria dynamics. Results Mathematical analysis for both the malaria models presented in this study was carried out and proved that all the models are mathematically and epidemiologically well-posed. We also compute the basic reproduction number R0 for both models and use the R0 to determine the local and global stability of the disease-free equilibriumas well as the local stability of endemic equilibrium of both models, respectively. We demonstrate that if R0 < 1, then the diseasefree equilibrium pointy of both models is locally and globally asymptotically stable, respevctively. However, if R0 > 1 the endemic equilibrium point of both models is locally asymptotically stable. The numerical results for both the models have demonstrated that the goal of intervention during malaria infection should be to reduce the rates at which merozoites and gametocytes invade healthy liver tissue as well as the blood cells. Hence it is recommended that interventions during malaria infection be directed on reducing the pace at which merozoites infect healthy blood cells and the density of merozoites in circulation. Conclusion The study presents a method that incoporates the complexity of malaria pathogens which is significant not only for malaria treatment but also for other vector-borne disease system control treatment strategies.
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A private sector-inclusive governance framework for local economic development in rural areas of Limpopo Province in South Africa
(2025-09-05) Jeleni, Albert; Francis, J.; Kilonzo. B.; Chakwizira, J.
Local Economic Development (LED) remains globally recognized as a critical instrument for building inclusive and globally competitive local economies by stimulating job creation, diversifying local economies, and broadening municipal revenue bases. The concept of LED was born out of the realisation that while economic development intent and principles (that of constructing and realising a sustainable future) are universal, the outcomes are bounded by national policies and priorities and are determined by specific local societal, environmental, and business characteristics and interactions, which, if not balanced properly, can distort/contradict economic development intent and principles, leading to inefficient economic development. LED therefore seeks to address these distortions by aligning universal principles with localised realities, while maintaining adherence to free-market economic principles and ensuring that local development interventions do not unduly disrupt market dynamics. Its effectiveness hinges on capturing grassroots knowledge—honouring local expertise and traditions—and innovating on these insights to realign local economic outcomes and maximise wellbeing in line with national imperatives and global agendas. However, in South Africa, particularly in the rural context of the Limpopo Province, LED implementation continues to face significant challenges. These are primarily rooted in systemic governance shortcomings, the exclusion of private sector participation, and the enduring legacy of state-centric approaches that have perpetuated poverty, high unemployment, and spatial inequalities stemming from apartheid-era development patterns. Rural Limpopo reflects these conditions acutely, with unemployment exceeding 45%, inequality exceeding Gini coefficient of 0.59, poverty levels surpassing 67%, less than 8% of municipalities received clean audits, and municipalities being heavily reliant on subsidies & bailouts, further exacerbated by inadequate infrastructure and weak institutional capacity. To counter these challenges, South Africa has consistently looked to Local Economic Development (LED) as a solution and has recently developed an innovation-driven National Framework for LED 2018–2028. The 2018–2028 LED Framework is robust in principle, anchored on forward-looking pillars designed to spur innovation, inclusivity, and institutional resilience at the municipal level. Yet, in practice, few municipalities have successfully implemented it, particularly the enabling pillars. This disconnect stems from weak institutional capacity, poor integration into municipal planning, and the low prioritisation of LED by local governments. Crucially, there has also been significant under-inclusion of the private sector, despite its vital role in driving innovation, investment, and job creation. Without active collaboration with private businesses—especially SMMEs—municipalities struggle to leverage innovation-driven strategies effectively, leaving the framework’s transformative potential largely untapped. Moreover, failure to implement the LED framework hinders the localisation of the Sustainable Development Goals (SDGs), weakening multi-stakeholder partnerships—including government, civil society, and the private sector—that are essential for achieving the SDGs. To investigate these challenges, this study employed a mixed-methods research approach, integrating quantitative surveys and qualitative focus group discussions conducted across all five districts of Limpopo Province to develop a private sector-inclusive governance framework. The research identified three critical governance failures that inhibit LED outcomes: (i) persistent ambiguity regarding the roles and responsibilities of key ecosystem actors—government, private sector, and civil society; (ii) misalignment between national strategic frameworks and local operational realities; and (iii) epistemic disparities that result in the underutilisation of private sector expertise, capital, and entrepreneurial capacity. These governance failures are further compounded by a fundamental conceptual ambiguity surrounding LED itself. Within the South African context, LED is frequently conflated with adjacent paradigms such as socio-economic development, socio-political development, social entrepreneurship, and entrepreneurship development. This lack of definitional clarity contributes to fragmented interventions, duplication of efforts, and missed opportunities for integrated and inclusive local development. As a result, LED implementation remains inconsistent, often disconnected from territorial needs, and inadequately aligned with the potential contributions of the private sector. To redress these deficiencies, the study developed a Private Sector-Inclusive Governance Framework for LED, structured around three interrelated platforms. The first platform—the Multi-Stakeholder Platform ("WHO")—formalizes the roles of stakeholders, institutionalizes collaboration within economic principles, and establishes shared decision-making structures. The second platform—allows setting of objectives and the respective Monitoring, Evaluation, and Adaptive Capacity Platform ("WHY")—anchors LED processes in objective-based continuous learning, performance tracking, and adaptive management, aligning with the six pillars of the South Africa’s National LED Framework (2018–2028) and the global Sustainable Development Goals (SDGs). The third platform—the Standardization and Implementation Platform ("HOW")— allows for the selection of appropriate LED elements, it applies a project management-oriented approach to guide LED operationalization, including value chain optimization across all sectors and industries. Crucially, the framework asserts that the actors (government, private sector and civil society) must operate within the principles of a free-market economy, wherein the state plays an enabling rather than interventionist role. Accordingly, local governments are encouraged to institutionalise mechanisms that promote inclusive Public-Private Partnerships (PPPs), leverage Corporate Social Responsibility (CSR) initiatives, and invest in Public Goods Services (PGS) to stimulate sustainable economic growth. The framework reconceptualises LED governance not as a substitute for market processes but as a catalyst. Free-market principles—fair competition, limited distortion, and entrepreneurial innovation—are foundational to the proposed model. The framework mandates the use of market diagnostics and cost-benefit analysis to determine the most efficient delivery mechanism—prioritising private sector-driven hybrid approach where viable, and public provision only where market failure exists. Wherefore, municipalities are repositioned as enablers of competitive innovative ecosystems, investing in public goods and unlocking market participation through regulatory clarity, digital access, and transparent procurement. This approach discourages the state from running parallel or competing programmes that undermine private sector participation, and instead calls for a governance model that incentivises market-based solutions and fosters long-term enterprise development. The proposed framework allows stakeholders to systematically select development objectives (the WHY) from multiple typologies (including innovation-driven, infrastructure-led, social cohesion, and sustainability objectives), choose the leadership style (the WHO) from among state-led, private sector-led, private sector-driven hybrid, state-driven hybrid, and civil society-driven hybrid models, and implement LED through specific elements (the HOW) such as anchors, intermediaries, infrastructure, governance networks, and citizen engagement Empirical findings demonstrate that only 35% of rural municipalities currently engage private sector actors meaningfully in LED governance, despite the private sector’s essential role in mobilizing financial resources, driving innovation, and facilitating scalable development. This study proposes an innovation-driven, private sector-driven hybrid approach, and knowledge-based governance framework for Local Economic Development (LED) in rural Limpopo, South Africa. Engaging 366 respondents—including 47.5% from the private sector and over 70% with post-school qualifications—it revealed that despite 92.4% awareness of municipal institutions, only 37.9% participated in LED processes, underscoring the limited leadership role of local businesses. A review of 27 global LED frameworks showed universal emphasis on sustainability and equity, but fewer than 50% integrate innovation and adaptive governance elements. The study further illuminates recurring local impediments included corruption (14.8%), funding shortages (11%), and skills gaps (12.3%). Sectors like mining and agriculture exhibited strong value-chain comprehension, whereas digital integration and advanced manufacturing capabilities remain weak. Despite 60.8% of respondents recognizing corporate support for SMMEs, only 24.1% reported tangible engagement, indicating missed opportunities for public–private synergy. These findings carry significant implications for Limpopo and broader South African LED strategies. An innovation-driven LED model would leverage private sector dynamism and foster knowledge-based value chains, aligning with Limpopo’s development objectives to become more industrialised, labour-absorbing, and globally integrated. To unlock this potential, LED policy must embed mechanisms for strengthened collaborative governance, streamlined funding, targeted capacity-building, and proactive private sector participation. Such a transformation could drive inclusive growth, reduce rural inequalities, and align with national priorities articulated in South Africa’s LED Framework and Limpopo Development Plan. The proposed framework conceptualises LED as a multi-objective optimisation problem, where local maxima are identified, filtered through Pareto dominance, and integrated into a global Pareto front—thus transforming local successes into globally relevant solutions. Accordingly, it incorporates a mathematical modelling component designed to operationalise this optimisation process and guide decision-making. Essentially, the framework proposes that LED strategy design should be systematic and iterative—a process optimization exercise that begins by selecting desired outcomes (e.g., innovation, jobs, sustainability) in the “WHY” Platform. From there, leadership style (state-led, private-led, community-led, or hybrid) is chosen in the “WHO” platform, and lastly the enabling elements (anchors, intermediaries, infrastructure, networks) are chosen in the “HOW” platform, considering local capacity and realities. Importantly, the approach remains adaptive, acknowledging that desired elements may not always be present, necessitating either phased development or immediate pragmatic choices. The framework offers a cohesive blueprint for South African municipalities to effectively implement the national innovation-driven LED Framework 2018-2028. South Africa having chosen innovation to drive LED, this proposed governance framework allows a logical selection of the innovation-driven, private sector-driven hybrid, and knowledge-based approach, positing that a sustainable Local Economic Development (LED) governance process must recognise the interdependent triad of innovation, private sector leadership, and knowledge intensity to be succesful. Innovation, as a driver of LED, requires an enabling environment that fosters private sector leadership, which, in turn, presupposes a knowledge-based economic governance architecture. This ensures LED is not aspirational but practically executable, grounded in clear mechanisms, data-informed strategies, and cross-sector collaboration. Moreover, the proposed governance framework offers a replicable pathway for translating policy into practice, unlocking LED’s full transformative potential, which is locally grounded, but globally relevant. Wherefore, from the policy perspective this study provides a comprehensive blueprint to transform South Africa’s rural LED by addressing critical shortcomings in the National Framework for Local Economic Development (LED) 2018–2028. First, it identifies the need to reposition the private sector as lead co‑creators—rather than peripheral participants—by formally embedding business chambers and forums into Integrated Development Plan (IDP) processes and making private sector consultation and leadership mandatory. Second, it introduces a practical governance framework aligned with the DST’s Innovation‑for‑LED (ILED) initiative and which must be piloted through the District Development Model (DDM). This model incorporates multi‑stakeholder platforms, standardized project tools, and performance monitoring systems, offering municipalities a scalable structure to boost coherence and accountability. Implementation hinges on building institutional capacity in rural municipalities. The study recommends targeted training programs for LED officials covering stakeholder engagement, value‑chain facilitation, project management, and digital monitoring tools. It further proposes institutionalizing public‑private dialogue (PPD) platforms co‑chaired by private sector actors and universities, guided by clear protocols on frequency, scope, and follow‑up. These platforms would serve as engines for knowledge management and innovation. On the fiscal front, the study advocates for performance‑linked grants and competitive LED innovation funds to incentivize municipalities to achieve measurable private sector participation, such as procurement localization rates, co‑infrastructure investments, and job creation via PPPs and CSIs. It also underscores the role of development partners and civil society in supporting framework adoption, recommending targeted piloting in Limpopo districts with international donor and institutional technical assistance. Institutional realignment is another key finding: responsibility for LED must shift from CoGTA and CoGHSTA to an economic development ministry—either via reinstating the Department of Economic Development or a reassignment to DTIC. At provincial level, LED oversight should align with Economic Development, Tourism, and Environment departments, with formal coordination mechanisms to link provincial, municipal, and national policy. Further, the Department of Small Business Development (DSBD) and its agency Small Enterprise and development Agnecy (SEDFA) currently perform welfare-style interventions—providing equipment and starter goods to micro/informal enterprises—which aligns more with social protection than market-based enterprise development. These micro-targeted supports overlook medium and large firms, which are vital for CSI, PPPs, and value chain integration critical to local economic development. Consequently, DSBD and SEDFA’s current mandate is misaligned with the NFLED’s private-sector growth objectives. Their national coordination role would be better housed under a re‑established Economic Development department or within DTIC, which has stronger linkages to industrial strategy and larger enterprises essential for transformative LED. Finally, the study links LED reform to the SDGs—particularly Goals 8, 9, and 17—by embedding SDG‑aligned indicators into municipal LED metrics and enhancing transparency, innovation, and data‑driven decision‑making. This positioned framework supports inclusive, private‑sector-driven hybrid growth, transforming LED from a bureaucratic process into a dynamic engine of rural transformation.
Open Access
AB INITIO and DFT computational study of Myristinin A and A structurally- related molecule
(2019-09-20) Tshilande, Neani; Mammino, Liliana; Ghio, Caterina
The computational study of biologically active molecules is particularly important for drug development because it provides crucial information about the properties of a molecule, which determine its biological activities. The current work considers the results of a computational study of myristinin A and a structurally-related molecule (2-(4-hydroxyphenyl)-4-[2,4,6-trihydroxy-3-(9tetradecenoyl)phenyl]-3,4-dihydro-2H-benzopyran-7-ol, here denoted as DBPO). The two compounds pertain to the class of acylphloroglucinols. They were firstly isolated from Horsfieldia amygdaline, and they exhibit a variety of biological activities, including potent anti-inflammatory activity, potent DNA-damaging activity and DNA-polymerase ß inhibition. Their molecular structures differ only by the acyl chain. Both molecules have a bulky substituent meta to the acyl group consisting of a ring system (2-(4-hydroxyphenyl)-3,4-dihydro-2H-chromen-7-ol). The DBPO molecule can exist as cis and trans isomers in relation to the double bond present in the R chain, and both isomers are here investigated individually. The OHs ortho to the acyl group can form an intramolecular hydrogen bond (referred to as the first IHB) with the sp2 O atom of the acyl group. The phenol OHs neighbouring the substituent ring system can form O–Hπ interaction with the aromatic rings of the substituent, if suitable oriented. This study focuses on the identification of the stable conformers of these molecules (considering all the possible geometries obtainable by rotations about relevant single bonds), and of the factors stabilising the conformers. Full-optimisation calculations were performed in vacuo and also in three conveniently selected solvents. The results show that the dominant stabilising factors are the first IHB and the O–Hπ interactions. Other factors which have significant influence on conformational preferences are the orientation of the ring systems of the substituent, the orientation of the OHs on substituent, the mutual orientation of the OHs of the phloroglucinol moiety and also the orientation of the acyl chain. The results in solution are consistent with the findings of other acylphloroglucinols, for instance, the narrowing of the energy gaps and the increase of the dipole moment with the increase of solvent polarity.
Open Access
Access and constraints to commuting in Gauteng Province, South Africa
(2016-05) Chakwizira, James; Bikam, Peter; Adeboyejo, Aina Thompson
See the attached abstract below
Embargo
Activation of the p53 pathway in combination with photon irradiation for the treatment of neurological tumour cells
(2026-05-19) Maluleka, Musa; Nemangwele, Fhulufhelo; Fisher, Randall; Engelbrecht-Roberts, Monique
Medulloblastoma (MB) and glioblastoma (GB) are highly aggressive brain tumours for which treatment outcomes remain poor, particularly due to intrinsic and acquired resistance to radiotherapy. Molecular determinants, especially TP53 status, play a critical role in regulating tumour cell proliferation, cell-cycle control, and DNA damage response following irradiation. This study investigated the biological effects of the MDM2 inhibitor AMG232 in combination with photon irradiation in TP53- wild-type and TP53-mutant MB and GB cell lines, with the aim of assessing whether AMG232 enhances radiosensitivity in a TP53-dependent manner. Cell proliferation, cell-cycle distribution, and DNA damage were assessed using growth assays, flow cytometry, and H2AX foci analysis, respectively. The findings showed that TP53 status strongly influenced cellular responses to treatment. TP53-wild-type cell lines demonstrated clearer growth control following AMG232 treatment, consistent with activation of functional p53 signalling. In contrast, TP53- mutant cell lines showed slower growth, inconsistent cell-cycle regulation, and weaker responses to AMG232, indicating limited recovery of p53 function. Cell-cycle analysis revealed that AMG232 induced a stronger and more sustained G0/G1 arrest in TP53-wild-type cells, supporting activation of the canonical p53–p21 axis. TP53-mutant cells displayed only partial or transient G0/G1 accumulation, suggesting the involvement of p53-independent stress responses rather than effective checkpoint enforcement. H2AX foci analysis confirmed a dose-dependent induction of DNA DSBs following photon irradiation across all cell lines. AMG232 treatment was associated with increased persistence of H2AX foci, particularly in MB cell lines, indicating impaired or delayed DNA repair. Residual foci at later time points reflected the predominance of error-prone non-homologous end joining, especially in G0/G1-arrested cells. In GB cell lines, DNA repair efficiency remained limited irrespective of treatment, highlighting intrinsic radioresistance. This study demonstrates that AMG232 enhances radiosensitivity primarily by prolonging DNA damage signalling and reducing DNA repair capacity, with effects that are most pronounced in TP53-wild-type cell lines. These findings highlight the importance of TP53 status in determining the therapeutic efficacy of MDM2 inhibition combined with photon irradiation and support the potential for molecularly guided treatment strategies in aggressive brain tumours.
Open Access
Activity patterns, species composition and dietary analysis of bats on two macadamia farms in Levubu, South Africa
(2017-09-18) Mphethe, Vusani; Taylor, P. J.; Steyn, J. N.; Schoeman, M. C.
See the attached abstract below
Open Access
Adaptation strategies for climate change-induced household food and nutrition insecurity in smallholder maize farming within Thulamela Local Municipality, South Africa
(2017-09-18) Mahlawule, Khanyisa Dorris; Francis, J.; Manjoro, D.
See the attached abstract below
Open Access
Adaptive Strategies to Mitigate Water Scarcity Among Smallholder Cattle Farmers in Vulnerable Areas of the Greater Tzaneen Local Municipality
(2024-09-06) Mahlo, Dollen; Manjoro, M.; Oloo, G. B.; Mkhwanazi, M. V.
The rapid increase in demand for livestock and livestock products, driven by factors such as population growth, urbanization, and rising incomes, is projected to escalate significantly by 2050. The estimates indicate the utilization of over 60 billion livestock for meat, egg, and dairy production. This surge in demand poses substantial challenges, particularly in the context of climate change impacts on water resources. Smallholder livestock farmers, who are integral to meeting this demand, are disproportionately affected by climate change-induced water scarcity. Despite their significant contribution to the agricultural Gross Domestic Product (GDP), these farmers face daily depletion of water reserves, indicating severe water scarcity. Climate variability further exacerbates this situation, with animal water consumption expected to triple. This study aimed to examine the adaptive strategies employed by smallholder livestock farmers in vulnerable areas of the Greater Tzaneen Local Municipality to mitigate water scarcity. A convergent parallel mixed methods design was utilized, wherein both quantitative and qualitative data were collected and analyzed concurrently. Purposive sampling was used to select participants, primarily through face-to-face interviews. Secondary data was obtained from literature, journal manuscripts, policy documents, and municipal reports. Quantitative data were analyzed using the Statistical Package for Social Sciences (SPSS) version 27, while thematic content analysis was performed using Atlas.ti version 8. The findings revealed several adaptive strategies employed by farmers to address water scarcity, including changes in water sources and collaborations with government agencies such as the Department of Water and Sanitation. Challenges such as cattle mortality due to water scarcity were also identified, highlighting the need for additional adaptive measures to ensure sustainable cattle farming. The study underscores the necessity of enhancing adaptive strategies to mitigate the adverse effects of water scarcity on smallholder livestock farming in the context of increasing climate variability.
Open Access
Adoption of survival strategies by agro-small and medium enterprises in the challenging rural environment in Zimbabwe
(2014-12-11) Shoko, Dumisani; Oloo, D.; Francis, J.
There is worldwide consensus among policy makers, economists and business experts that Small and Medium Enterprises (SMEs) contribute substantially to aggregate economic growth. Agro-SMEs in particular, are regarded as the engines of economic growth and catalysts of socio-economic transformation in many countries. However, the resilience of agro-SMEs is increasingly becoming questionable due to a number of challenges which include, economic recession and climate change. Economic recession and climate change pose formidable challenges to the survival and growth of agro-SMEs. These complex challenges and barriers compel! agro-SMEs to adopt survival strategies in order to remain operational. Strategies that can appropriately enhance the resilience of agro-SMEs to shocks and how best to implement them, are still unknown. Thus, this case study investigated the survival strategies that were adopted by agro-SMEs in Kwekwe District of Zimbabwe in response to economic recession and climate change induced-stress between the year 2000 and 2010. All the agro-SMEs established before 2005, that survived the 2000-2010 challenging operating environment and were still operational during the time of the research, constituted the study population. Purposive sampling in the form of total population sampling was used. The main data collection tools that were used to gather data to answer the objectives of the study are appreciative inquiry, using key informant interviews and questionnaire survey; preference ranking using matrix scores; data mining of records kept by agro-SMEs government publications, journals and related books; and comparative scaling. The Statistical Package for Social Sciences (SPSS) was used to analyse the data. Thematic content analysis, frequency distribution analysis, measures of central tendency and the Binary Logistic Regression Model were used to analyse specific objectives of the study. Results show that a variety of strategies are available for adoption by agro-SMEs operating in a challenging environment. Adoption rates and preferences varied from one strategy to the other. Contribution of these strategies towards agro-SME survival also varied from no contribution at all to marginal to significant or very significant contribution.The study's results provide compelling scientific information that will act as a guideline on the strategies that can be adopted in challenging operating environments. This will also assist in the creation of a better platform for the implementation of improved agro-SME development strategies.
Open Access
Adsorption of oxyanions of As, B, Cr, Mo and Se from coal fly ash leachates using A1/Fe modified bentonite clay
(2014-01-10) Masindi, Vhahangwele; Gitari, Wilson Mugera; Tutu, Hlanganani
South African coal-fired power stations rely on the use of low grade bituminous coal for electricity generation. During coal combustion processes, this type of coal generates large volumes of waste materials which include Fly ash, bottom ash, boilers slag, flue gas desulphurization and un-captured particles. From the array of generated residues, coal fly ash constitute 90% and of this only 5% is beneficially used with the rest being disposed-off to land as ash dumps or slurried to ash retention ponds. On disposal, coal fly ash leaches out toxic chemical species on contact with the aqueous media hence posing hazardous effects to the aquatic and terrestrial environment. Of prime concern are Oxyanionic species such as As, B, Cr, Mo and Se. This study aims to investigate the adsorption of As, B, Cr, Mo and Se from coal fly ash leachates on Al3+/Fe3+modified bentonite clay. Coal fly ash samples used in this study were collected from Tutuka, ESKOM power plant in Mpumalanga and Bentonite clay samples were collected from ECCA (pty) Ltd. pH, Electrical Conductivity (EC) and Total Dissolved Solids (TDS) of the samples were determined using a CRISON multimeter probe. Modifications of bentonite clay with Al3+ and Fe3+ cations were done in batch procedures and the parameters optimized included contact time, adsorbent dose and adsorbate concentration. Cation Exchange Capacity (CEC), Point of Zero Charge (pHpzc) and Water Holding Capacity (WHC) of raw and modified bentonite clay were determined using standard methods. Surface areas of raw and modified bentonite clays were determined by BET. Elemental composition of raw and modified bentonite clay was determined by XRF and Mineralogical composition of raw and modified bentonite clay was determined by XRD. AAS and GFAAS were used to monitor AI3+and Fe3+concentration in the reaction mixture during and after modification while As, B, Cr, Mo, and Se were monitored using GFAAS, ICP- OES and JCP- MS. Adsorption of oxyanions of As, B, Cr, Mo and Se was carried out in batch experiments using synthetic solutions of the species. Effects of contact time, adsorbent dosage, adsorbate concentration and pH on the adsorption of As, B, Cr, Mo and Se were evaluated and optimized. The modification experiments revealed that loading of Al3+ onto bentonite clay interlayers is optimum at 60 minutes of contact time, 3 grams of adsorbent and 100 mg/L of adsorbate concentration and loading of Fe3+ onto bentonite clay matrices is optimum at 15 minutes of contact time, 2 grams of adsorbent and 100 mg/L of adsorbate. The CEC results showed that South African bentonite clay is characterized by high CEC of262 meq/l00g at pH 5.4 and 265.5 meq/l00g at pH 7.4 which decreased to 186.9 meq/l00g at pH 5.4 and 183.3 meq/l00g at pH 7.4 on introducing Al3+ onto bentonite clay interlayers and 195.5 meq/100g at pH 5.4 and 188.9 meq/100g at pH 7.4 on introducing Fe3+ onto bentonite clay interlayers. The results show that CEC is independent of pH. BET results indicated that the loading of Al3+ onto bentonite clay interlayers increased the surface area from 16 m2/g to 44.3 m2/g and 50 m2/g for Fe3+,external surface area from 11.1 m2/g to 33.1 m2/g for Al3+ and 37.4 m2/g for Fe3+,micro-pore area from 4.9 m2/g to 11.2 m2/g for AJ3+ and 12.5 m2/g for Fe3+. There was a slight difference in pHpzc of Al3+ modified bentonite clay (8.2) as compared to raw bentonite (8.0). For Fe3+ modified bentonite clay, the pHpzc was observed to increase from 8.0 for raw bentonite clay to 9.0. An increase in pHpzc shows that modification will favour adsorption of anions from aqueous media. WHC of bentonite clay was determined to be 42.7%. Elemental composition by XRF showed SiO2, AhO3, Fe2O3, CaO, Na2O, K2O and MgO as the major chemical species. XRF results also confirmed that bentonite clay is an aluminosilicate material. XRD disclosed that bentonite clay is dominated by montmorillonite as the major mineral phase. Characterization of fly ash leachates revealed that coal fly ash leachates contains 53 µg/L of As, 1730 µg/L of B, 271 µg/L of Cr, 165 µg/L of Mo and 170 µg/L of Se. Adsorption of As, B, Cr, Mo and Se onto Al3+ modified bentonite clay revealed that 30 minutes of contact time, 4 grams of adsorbent dosage, 10 mg/L of adsorbate concentration and pH 10 are the optimum conditions for removing those species from aqueous media. The adsorption affinity of those species obeyed the following order: B = Se > Mo = Cr > As. Adsorption of As, B, Cr, Mo and Se onto Fe3+ modified bentonite clay revealed that 30 minutes of contact time, 4 grams of adsorbent dosage, 10 mg/L of adsorbate concentration and pH 10 are the optimum conditions for removing those species from aqueous media. The adsorption affinity of those species obeyed the following order: B = Se > Mo > Cr = As. The adsorption capacities of modified bentonite clays were greater than the adsorption capacities of raw bentonite clay. The data fitted well to both Langmuir and Freundlich adsorption isotherm hence showing that the adsorption is energetically favourable. The unmodified clay showed poor adsorption for these chemical species. Both Al3+ and Fe3+ modified bentonite clay successfully removed As, B, Cr, Mo and Se from generated coal fly ash leachates to below DWAF water quality guidelines at the optimized conditions. This shows that AJ3+ or Fe3+ modified bentonite clay is an effective adsorbent for removal of oxyanionic species of As, B, Cr, Mo and Se from coal fly ash leachates and could be applied as a reactive barrier or liner in ash retention ponds.
Open Access
Agronomic evaluation of chickpea (Cicer arietinum L.) genotypes in contrasting agro-ecological regions of Limpopo and Mpumalanga Provinces
(2020-02-24) Shilenge, Siphiwe Kim; Ogola, J. B. O.; Odindo, A.
Chickpea (Cicer arietinum L.) is an important grain legume in the world, ranking second after soybean (Glycine max L.). It accounts for a substantial proportion of human dietary nitrogen intake and plays a crucial role in food security in developing countries. Chickpea can grow in areas with low rainfall and poor soils, and thus may be an important food security crop for smallholder resource-poor farmers in the semi-arid tropics such as the dry environments of the Limpopo and Mpumalanga Provinces of South Africa. Preliminary studies showed the huge potential of chickpea production in these environments. However, no suitable genotypes have been identified and recommended for different agro-ecological zones of Limpopo and Mpumalanga Provinces. Therefore, the objective of this study was to evaluate the performance, and hence, identify the genotypes that are adapted/suitable to the contrasting agro-ecological conditions of Limpopo and Mpumalanga Provinces for production. Field experiments were conducted in the winter cropping seasons of 2016 and 2017 at Thohoyandou (University of Venda experimental station), Syferkuil (University of Limpopo experimental station) and Nelspruit (University of Mpumalanga experimental station). Ten desi chickpea genotypes were sown in a completely randomized block design replicated three times on 10 May 2016 and 10 April 2017 (Thohoyandou), 13 May 2016 and 11 April 2017 (Syferkuil) and 03 May 2016 and 24 May 2017 (Nelspruit). Plant growth characteristics were assessed by determining plant height, crop phenology, number of primary and secondary branches, and canopy cover. Yield and yield components were assessed at harvest after physiological maturity. Carbon dioxide exchange rates (CER) was determined at different growth stages using the InfraRed Gas Analyzer (IRGA). Chlorophyll content (CC) and intercepted radiation were determined weekly using the chlorophyll content meter (CCM-200 PLUS, Opti-Science, Tyngsboro, Massachusetts), and the AccuPAR, LP-80 ceptometer (Deacon Devices Ltd., Pullman, USA), respectively. Genotypes did not vary in CC at Thohoyandou in all seasons, but CC increased with stages of growth. Genotypes varied in the proportion of intercepted radiation (IR) at all measurement dates in Thohoyandou during the 2016 and 2017 growing seasons. The proportion of IR increased with growth stage, reached a peak and declined with plant age. Genotype affected photosynthesis and intercellular CO2 concentration (Ci) but did not have any significant effect on stomatal conductance (gs), transpiration (T) and Leaf Vapour Pressure Deficit (VPDL) during the 2016 season in Thohoyandou. In contrast, genotype did not affect photosynthesis, Ci, gs, T and VPDL in the 2017 season in Thohoyandou. There was no variation among genotypes on number of primary and secondary branches in Thohoyandou in both seasons. Genotypes showed no variation in plant height in the 2016 season in Thohoyandou agro-ecological condition. However, genotypes showed significant variation in plant height at 14, 70 and 84 days after emergence (DAE) in the 2017 cropping season. Moreover, genotypes showed significant variations in days to 50% flowering in Thohoyandou during the 2016 season, but showed no variations in days to 50% emergence and 75% physiological maturity. Genotypes showed no variations in days to 50% emergence, 50% flowering, 50% podding and 75% physiological maturity in the 2017 season in all locations. Genotypes showed significant variation in grain yield in Syferkuil agro-ecological condition, but showed no significant variations on all the other studied traits, while genotypes varied in 100 seed weight (SW) in Thohoyandou, but did not show any variations on the other studied traits during the 2016 season. Moreover, genotypes did not vary for all studied traits in Nelspruit during the 2016 season. The 2016 genotype and environment (G X E) interaction results showed no significant variations. However, results showed G X E interactions during the 2017 growing season suggesting that genotypes responded to environmental variation in a different way. Syferkuil had the greatest grain yield (2811 kg ha-1 and 3122 kg ha-1) in both the 2016 and 2017 growing seasons respectively, as compared to Thohoyandou and Nelspruit. These preliminary findings show that the studied genotypes responded differently in contrasting agro-ecological regions of Limpopo and Mpumalanga Provinces and that Syferkuil might be the best environment for chickpea production in this region due to its cooler temperatures. Of the genotypes evaluated the most promising genotypes are ICCV8101, ICCV3203 and ICCV4110 in these regions in terms of grain yield.
Open Access
Alternative methods for solving nonlinear two-point boundary value problems
(2018-03-18) Ghomanjani, Fateme; Shateyi, Stanford
In this sequel, the numerical solution of nonlinear two-point boundary value problems (NTBVPs) for ordinary di erential equations (ODEs) is found by Bezier curve method (BCM) and orthonormal Bernstein polynomials (OBPs). OBPs will be constructed by Gram-Schmidt technique. Stated methods are more easier and applicable for linear and nonlinear problems. Some numerical examples are solved and they are stated the accurate findings.