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Item Combustion characteristics of dual swirl low nitrogen burners in small gas boilers(2025) Xiangyun, L; Zhu, L; LiangDe, L; XiuFang, K; Haitao, ZhengSwirl combustion technology is an effective method for achieving low-nitrogen (low NOx) combustion. In this study, we designed a dual-swirl low-NOx burner with the goal of minimizing NOx emissions. and the burner was evaluated in a 20t/h gas boiler through numerical simulation and experimentation. Swirl angles and excess air coefficients (1.0 to 1.20) of the burner were tested within the range of 1.0 to 1.2. The results indicated that the optimal swirl plate angles were 35° internally and 55° externally. The optimal excess air coefficient was 1.15, which balances heat transfer efficiency and minimize NOx emissions. Results show that the dual swirl combustion system can effectively reduce nitrogen oxide emissions in small gas boilers.Item Cross-realm biodiversity profile of the South African coastal zone(2025-04) Harris, LH; Adams, JB; Dayaram, A; Dunga, LV; Job, N; Kirkman, SP; Lamberth, SJ; Pfaff, MC; Van Deventer, Heidi; Van Niekerk, LaraSouth Africa’s coast is 3 113 km long and includes microtidal shores that experience semi-diurnal tides and mostly high wave energy. From west to east, the cool Benguela Current and the warm Agulhas Current drive steep gradients in climate and environmental conditions, resulting in diverse coastal ecosystem types. Here, we review the biodiversity of South Africa’s coastal zone, focusing on the constituent ecosystem types from the terrestrial, freshwater, estuarine and marine realms, and provide a brief overview of cross-realm biodiversity patterns. We also give guidance on coastal boundaries to improve standardisation in this complex area to support assessment, planning and management. The ecologically determined coastal zone currently comprises 193 ecosystem types: 83 vegetation types (e.g. seashore vegetation, strandveld, duneveld, coastal forest); 22 estuary and 3 micro-estuary ecosystem types; and 85 marine ecosystem types (e.g. shores, islands, reefs, kelp forests, bays), with planned inclusion of freshwater types (e.g. coastal lakes, forested wetlands, dune slacks) in the future. Species richness is generally highest along the south and east coasts, with the highest levels of endemism mostly reported for the south coast. The South African coast is a national asset that warrants careful management for long-term sustainability to safeguard its unique biodiversity and many associated benefits for current and future generations.Item Healthy estuaries enhance climate change resilience for fish within South African coastal seascapes(2026-07) James, NC; Edworthy, C; Van Niekerk, Lara; Lamberth, SJ; Adams, JB; Whitfield, AK; Deyzel, SHPThe capacity for estuaries in coastal seascapes to locally mitigate the effects of regional climate change should be considered in adaptation planning. In this paper we review work undertaken in South Africa’s warm-temperate estuaries to examine factors that promote climate change resilience for estuaries and associated fish and also the potential refuge provided by estuaries from climate change impacts within coastal seascapes. The thermal refuge provided by the middle and upper reaches of permanently open marine dominated estuaries for fish species is illustrated from long-term temperature monitoring in estuaries and adjacent coastlines. During extreme temperature events in the nearshore and lower estuary reaches, minimal thermal variability is maintained in middle and upper estuarine reaches, thus providing biota with a refuge against extreme thermal variability. In healthy estuaries seagrass meadows are particularly important nursery habitats, which have the added ecosystem service of maintaining pH stability and providing ocean acidification refuges for associated fauna. However, this refuge potential (resilience) declined when high water temperatures associated with a marine heat wave, interacting with nutrient enrichment, caused macroalgae blooms in seagrass meadows. We identified estuaries in the warm-temperate region that potentially provide temperature and pH refuge based on their key features (connection to the sea, habitat availability and extent). In the warm-temperate seascape 13 estuaries with marine dominated middle reaches potentially provide thermal refuge for stenohaline species seeking refuge from thermal stress. Extensive seagrass beds potentially providing ocean acidification refuges are found in 10 of these 13 estuaries. Fish communities in healthy refuge estuaries (defined as estuaries with minimal habitat alteration and loss) are more resilient to climate change impacts than those in altered systems, with eutrophication being the primary anthropogenic driver of change.Item Exploring metallic nanoparticles for enhanced multiplexed SERS for diagnostics(2025-03) Thwala, Nomcebo L; Thobakgale, Setumo L; Mcotshana, Zenande KS; Tlomatsane, Moratoa HC; Ombinda-Lemboumba, Saturnin; Lugongolo, Masixole Y; Mthunzi-Kufa, PatienceWhen it comes to diagnostics and disease management, while physicians focus on the prognosis and mortality caused by viral diseases, it is necessary to be thorough about metabolic chronic illnesses that could cause complications. Owing to its remarkable sensitivity and capability for multiplexing, Surface-Enhanced Raman Spectroscopy (SERS) emerges as a potent analytical approach with substantial promise in the realms of bioanalysis and diagnostics. This work focuses on exploring metallic nanoparticles that can be used for SERS- based pathogen and metabolic disorder-biomarkers detection for rapid viral infection and chronic disease diagnosis using SARS-CoV-2 or HIV pseudo-virus and a diabetes biomarker, glucose. Herein, metallic nanoparticles (NPs) such as gold (Au) and silver (Ag) nanoparticles, were assessed for their sensitivity in detecting both disease-biomarkers in a buffer containing HIV pseudo-virus and glucose.Item Synthesis of an 8-membered oxygen-containing benzo-fused heterocycle using flow technologies – an exercise in undertaking research with sustainability as a driver(2025-03) Currie, BM; Neyt-Galetti, NC; Olivier, T; Van der Merwe, P; Dibokwane, LS; Reinhardt, AM; Van Wyk, LT; Panayides, Jenny-Lee; Rile, DLDue to their natural abundance and biological properties, benzo-fused heterocycles are attractive targets in the field of drug discovery. Previously, a synthetic strategy for accessing 5-, 6-, 7- and 8-membered oxygen-containing benzo-fused heterocycles with the oxygen atom in the less commonly encountered 2-position was reported, however, the approach was hindered by long reaction times and a reliance on high boiling point solvents such as DMF. Targeting an 8-membered analogue as an exemplar, we highlighted that the adoption of basic green chemistry principles coupled with the use of flow chemistry techniques could be utilised (with limited development time) to improve day-to-day sustainability when performing synthetic research. In the case in hand, several key improvements were noted including (i) a higher overall yield (37% vs. 26%), (ii) a significantly reduced reaction time (110 min vs. 136 h) and (iii) the avoidance of the undesirable solvent DMF.Item Design of energetic molecular hybrids of 2-(dinitromethylene)-1,3-diazacyclopentane (DNDZ) and calculation of their detonation performance parameter(2025-07) Thungatha, Lamla; Ngcebesha, Pholisa; Mahlase, Andrew CKTheoretical design of molecular hybrids of 2-(dinitromethylene)-1,3-diazacyclopentane (DNDZ) (a derivative of FOX7) was done by linking the DNDZ to known energetic materials via a -CH 2- chain. A total of 12 novel molecular hybrids of DNDZ were designed, and their performance parameters were studied computationally. All the calculations for the molecules were done successfully to obtain these properties, which were further compared with DNDZ and RDX. Molecule 1, a hybrid of DNDZ and 2,3,4,5-tetranitro-1H-pyrrole, performed way better than the rest of the molecules and even better than DNDZ and RDX. As much as this molecule has the best detonation parameter, it is very sensitive to impact with the calculated impact sensitivity (IS) of 6 J. Molecule 12 has detonation performance better than all the molecules except molecule 1, and it has a good balance between detonation performance and impact sensitivity as compared to molecule 1.Item The Settlement-mesozone geo-frame: An evolving spatial data framework facilitating data integration in support of South Africa’s development planning(2025) Arnold, Kathryn A; Maritz, Johan; Mans, Gerbrand GIn the development planning domain, there is a critical need for enhanced understanding of the complex spatial dynamics of social, economic and environmental patterns. Data are a critical resource for evidence-based planning and decision-making, and the 2030 Agenda for Sustainable Development has underscored the need for harmonised data of increasingly high quality, accuracy, currency, timeliness and granularity to effectively measure and monitor progress towards the Sustainable Development Goals at global, regional, national and subnational levels. Integrating geospatial and statistical data is one of the most effective ways to maximise its value, and while data integration methods are well documented and widely applied, less attention has been given to determining the most suitable spatial units for publicly useable, policy-informing data. A key challenge lies in the varying units of analysis and geographical scales employed across sectors and scientific disciplines. In South Africa, the Settlement-Mesozone Geo-Frame was developed and has evolved over 20 years of focused research and development to address issues inherent in the geographically arbitrary administrative areas according to which official data are collected and reported. The geo-frame provides a robust foundation for integrating spatially misaligned national datasets, enabling better profiling, mapping, analysis and monitoring of places over space and time.Item Black carbon emissions generally underestimated in the global south as revealed by globally distributed measurements(2025-07) Ren, Y; Oxford, CR; Zhang, D; Liu, X; Zhu, H; Dillner, AM; White, WH; Chakrabarty, RK; Garland, Rebecca M; Naidoo, MogeshCharacterizing black carbon (BC) on a fine scale globally is essential for understanding its climate and health impacts. However, sparse BC mass measurements in different parts of the world and coarse model resolution have inhibited evaluation of global BC emission inventories. Here, we apply globally distributed BC mass measurements from the Surface Particulate Matter Network (SPARTAN) and complementary measurement networks to evaluate contemporary BC emission inventories. We use a global chemical transport model (GEOS-Chem) in its high-performance configuration (GCHP) for high-resolution simulations to relate BC emissions to ambient concentrations for comparison with measurements. Here we find that simulations using the Community Emissions Data System (CEDS) emission inventory exhibit skill (r2 = 0.73) in representing variability in SPARTAN measurements across primarily developed regions with low BC concentrations but exhibit pronounced discrepancy (r2= 0.00019) across high-BC regions in the Global South, underestimating BC by 38%. Alternative inventories (EDGAR, HTAP) yield similar results. These findings motivate renewed attention to the challenging task of characterizing BC emissions from low- and middle-income countries.Item Effects of encapsulation and in vitro digestion on anthocyanin composition and antioxidant activity of raspberry juice powder(2025-07) Mokale, MJ; Kesavan Pillai, Sreejarani; Sivakumar, DMicrobeads of raspberry extract were produced using encapsulation matrices alginate + pea protein isolate + psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid using freeze-drying method. The microbeads were characterised and assessed for their effectiveness on the release, bioaccessibility, of anthocyanin components and antioxidant activities during in vitro digestion. Alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid matrix showed the highest encapsulation efficiency of 91.60% while the lowest encapsulation efficiency was observed in alginate + pea protein isolate + psyllium mucilage + okra (69.94%). Scanning electron microscope images revealed spherical shapes and varying surface morphologies for different encapsulation matrices. Despite the differences observed in Fourier transform infrared spectra, microbeads showed similar thermal degradation patterns. X-ray diffractograms showed amorphous structures for different encapsulation matrices. Comparatively, alginate+ pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid microbeads exhibited the highest bioaccessibility for total phenols (93.14%), cyanidin-3-O-sophoroside (54.61%), and cyanidin-3-O-glucoside (55.30%). The encapsulation matrices of different biopolymer combinations (alginate+ pea protein isolate+ psyllium mucilage, alginate + pea protein isolate + psyllium mucilage + okra, and alginate + pea protein isolate + psyllium mucilage + Aloe ferox gel + gallic acid) enhanced anthocyanin stability and protected it against in vitro degradation of bioactive compounds.Item Advances and challenges in betulinic acid therapeutics and delivery systems for breast cancer prevention and treatment(2025-09) Selepe, Cyril T; Dhlamini, Khanyisile S; Tshweu, Lesego L; Kwezi, Lusisizwe; Ramalapa, Bathabile E; Ray, Suprakas SBreast cancer (BC) is the leading cause of cancer-related death among women worldwide. Due to limited treatment options for patients with advanced BC, preventive and innovative therapeutic strategies are essential to combat this disease. Therefore, finding safe and effective anticancer treatments remains a significant challenge in the 21st century. Plant-derived triterpenoids, widely used for medicinal purposes, exhibit various biological activities. Most triterpenoids are cytotoxic to multiple tumor cells and demonstrate anticancer effects in preclinical animal models. One example is betulinic acid (BA), a natural product mainly extracted from the bark of birch trees. BA is a promising anti-tumor compound with numerous pharmacological properties. However, its poor water solubility limits its optimal therapeutic potential. Additionally, the low BA content in plants hampers large-scale production from these sources. To address these issues, extensive research has focused on producing BA through chemical synthesis and biotransformation. Furthermore, several BA derivatives have been developed through structural modifications, and various delivery systems have been created to improve solubility and enhance therapeutic efficacy. This review discusses recent advances and challenges related to BA and its derivatives in preventing and treating breast tumors, as well as the potential obstacles and future directions for improving delivery systems in BC therapy.Item A review of smart crop technologies for resource constrained environments: Leveraging multimodal data fusion, edge-to-cloud computing, and IoT virtualization(2025-10) Olatinwo, DD; Myburgh, HC; De Freitas, A; Abu-Mahfouz, Adnan MISmart crop technologies offer promising solutions for enhancing agricultural productivity and sustainability, particularly in the face of global challenges such as resource scarcity and climate variability. However, their deployment in infrastructure-limited regions, especially across Africa, faces persistent barriers, including unreliable power supply, intermittent internet connectivity, and limited access to technical expertise. This study presents a PRISMA-guided systematic review of literature published between 2015 and 2025, sourced from the Scopus database including indexed content from ScienceDirect and IEEE Xplore. It focuses on key technological components including multimodal sensing, data fusion, IoT resource management, edge-cloud integration, and adaptive network design. The analysis of these references reveals a clear trend of increasing research volume and a major shift in focus from foundational unimodal sensing and cloud computing to more complex solutions involving machine learning post-2019. This review identifies critical gaps in existing research, particularly the lack of integrated frameworks for effective multimodal sensing, data fusion, and real-time decision support in low-resource agricultural contexts. To address this, we categorize multimodal sensing approaches and then provide a structured taxonomy of multimodal data fusion approaches for real-time monitoring and decision support. The review also evaluates the role of IoT virtualization as a pathway to scalable, adaptive sensing systems, and analyzes strategies for overcoming infrastructure constraints. This study contributes a comprehensive overview of smart crop technologies suited to infrastructure-limited agricultural contexts and offers strategic recommendations for deploying resilient smart agriculture solutions under connectivity and power constraints. These findings provide actionable insights for researchers, technologists, and policymakers aiming to develop sustainable and context-aware agricultural innovations in underserved regions.Item Fire-retardant wood polymer composite to be used as building materials for South African formal and informal dwellings — A review(2025-02) Maake, T; Asante, JKO; Mhike, W; Mwakikunga, Bonex WA demand to replace an easily combustible wood with wood–plastic–rubber composite with better thermal performance than wood is at its peak globally. Wood-based composite materials in the form of wood–polymer composite (WPC) have emerged as new materials that can replace wood to produce wood products for various use. The use of recycled polymers as biodegradable polymer blended with fiber particles, waste tire powder, and other substances to manufacture new products known as wood–rubber–plastics composite (WRPC) for building construction and other different applications, has piqued the interest of numerous researchers. High flammability and weak combustibility parameters are a setback for many wood-based composites because of the flammability of these composites. Fabricated WRPC based on non-toxic fire retardants and other additives used to modify the flame-resistant quality of these composites, the fabrication techniques, and mechanical characteristics are herein reviewed. It is hoped that better composite in the form of WRPC can be used as building materials for informal and formal dwellings.Item An empirical evaluation of the main factors of a cybersecurity culture in South African E-health institutions using multiple linear regression(2025-08) Mwim, NE; Mtsweni, Jabu S; Chimbo, BE-health institutions are prominent targets for cybercriminals due to their reliance on information technology systems and issues related to the users have been identified as the biggest security weakest. Hence, while cybersecurity culture (CSC) research emphasizes the necessity of the human factor, limited empirical work has been done in the context of e-health in Africa. Therefore, an empirical evaluation was conducted to identify how preparedness, responsibility, management, technology and environment influence cybersecurity in South African e-health institutions. This quantitative research studied e-health institutions in the Mpumalanga province of South Africa. Various methods were used to investigate the multiple linear regression effects of the main factors of CSC and the results show that although the preparedness (Beta = 0.281; p-value < 0.05) and environment (Beta = 0.500; p-value < 0.05) factors had the greatest influence, management, technology and environment had a positive effect on CSC. These factors contributed 48.2 % to the variance (R-Squared). The study seems to be the first empirical study that combines the human factor domain framework (HFD) with other theoretical frameworks to identify critical factors of CSC. Furthermore, the impact of technology on CSC was empirically tested. The study is significant as it identified key factors that contributed to the institution’s CSC and quantified their impact. These results can enable e-health institutions to make decisions based on evidence regarding their cybersecurity interventions, strategy and practices. However, the empirical evaluation was limited to one context, namely the Mpumalanga province in South Africa and at two hospitals selected based on easy access (convenience) and purposive sampling with criteria based on work experience and knowledge of CSC limited the number of participants eligible to participate.Item Meteorological Drought Trend Analysis and Forecasting Using a Hybrid SG-CEEMDAN-ARIMA-LSTM Model Based on SPI from Rain Gauge Data(2026-01) Sibiya, S; Ramroop, S; Melesse, S; Mbatha, Nkanyiso BMeteorological drought presents considerable challenges to water supplies, agriculture, and socio-economic stability, especially in areas heavily reliant on precipitation. The Standardized Precipitation Index (SPI) is esteemed for its efficacy in drought monitoring, owing to its straightforwardness and applicability across many time scales. This study examines meteorological drought dynamics in the uMkhanyakude district using the Standardized Precipitation Index (SPI) at 6-, 9-, and 12-month timescales. Trend analysis was conducted using Mann–Kendall (MK), Modified Mann–Kendall (MMK), and Innovative Trend Analysis (ITA) methods. The study also proposes a hybrid model that integrates the Savitzky–Golay (SG) filter, Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN), Autoregressive Integrated Moving Average (ARIMA), and Long Short-Term Memory (LSTM) networks, referred to as SG-CEEMDAN-ARIMA-LSTM, for forecasting of the SPI time series. Analysis of SPI trends and variability revealed statistically significant declining trends at five monitoring stations, characterized by negative Z-scores and p-values, showing a marked downward trajectory across several SPI scales. On the other hand, the forecasting results demonstrate that the SG-CEEMDAN-ARIMA-LSTM methodology outperformed benchmark models across all temporal scales, achieving high prediction accuracy with R2 values of 0.9839 (SPI-6), 0.9892 (SPI-9), and 0.9990 (SPI-12). These findings highlight the effectiveness of decomposition techniques (SG, CEEMDAN) in enhancing model performance and confirm the suitability of the hybrid model for both short-term and long-term drought forecasting. This study merges robust trend analysis with advanced hybrid forecasting techniques, providing a reliable framework for early warning systems and sustainable water resource management in drought-prone regions.Item Hybrid perovskite solar cells: A disruptive technology for hydrogen production through photocatalytic water splitting(2025-08) Akin Olaleru, S; Palaniyandy, N; Mamba, BB; Mwakikunga, Bonex WPerovskite solar cells (PSCs) have recently emerged as a viable technology for photovoltaic applications, offering high efficiency and cost-effective manufacturing. Beyond generating electricity, PSCs can also facilitate hydrogen production through water splitting. This article provides a comprehensive review of current research on PSCs for hydrogen production, highlighting their potential as a transformative technology in this field. The challenges and opportunities associated with using PSCs for hydrogen production are discussed, including their stability and efficiency under various operating conditions. The impact of device design, system integration, and materials engineering on PSC performance for hydrogen production is also examined. Furthermore, an overview of hydrogen demand is provided and how PSCs can be integrated with other renewable energy sources to contribute to a sustainable energy future through green hydrogen production is explored. The analysis suggests that hydrogen production using PSCs has the potential to become a groundbreaking technology, significantly impacting the energy sector and the transition to low-carbon energy.Item A novel hybrid path loss prediction model for 5G midband networks using empirical, machine learning, and feature prioritization techniques(2025-12) Shaibu, FE; Onwuka, EN; Salawu, N; Oyewobi, SS; Abu Mahfouz, Adnan MIAccurate path loss prediction is vital for 5G deployment, especially at midband frequencies where signal degradation is significant. This paper presents a hybrid model that integrates an optimized COST-231 Hata model with a random forest algorithm to improve prediction accuracy at 3.5 GHz. Recursive feature elimination identified eleven key features from eighteen multidimensional parameters, including novel environmental attributes, to prioritize factors influencing urban path loss. Validation against measurement and simulation datasets showed strong alignment with observed results, achieving lower errors (MAE = 1.82 dB, RMSE = 2.05 dB, and MAPE = 2.4%) compared to existing models. Additionally, cross-band validation at 1.6 GHz further demonstrated the model’s robustness, though retraining or fine-tuning is recommended for optimal performance at lower frequencies. Future research may expand the dataset to enhance generalizability.Item Colorimetric detection and removal of copper(II) ions from wastewater using a Griess reagent and cellulose nanofibers supported with mesoporous silica nanoparticles: An ImageJ and CIELAB colour space-based analytical approach(2025-12) Ninela, AM; Shange, SF; Mtibe, Asanda; Andrew, Jerome E , Jerome E Mokhothu; Mokhothu, THThis study presents a green, cost-effective, and dual-function approach for the colorimetric detection and removal of copper ions (Cu(II)) in wastewater, utilizing a cellulose nanofiber–mesoporous silica nanoparticle (CNF-MSN) composite in conjunction with the Griess reagent. The CNF-MSN composite was synthesized via a sol–gel process using cellulose nanofibers derived from natural biomass. Comprehensive characterization using FTIR, SEM, XRD, BET, TEM, and TGA confirmed the successful integration of CNF and MSN, with TEM revealing a web-like nanofiber structure (∼33 nm) and SEM showing mesoporous silica nanoparticles (2–50 nm). Hydrogen bonding between CNF hydroxyl groups and MSN silanol groups was indicated by O–H stretching shifts. For Cu(II) detection, the CNF-MSN composite produced a visible purple color change upon reaction with the Griess reagent across 1–5 mg/L Cu(II) standards. Color intensity and RGB values were quantified using ImageJ, converted to CIEXYZ and CIELAB (Lab) values, resulting in a linear response (R² = 0.9956) over the range of 0.01–5 mg/L, with a detection limit of 0.001521 mg/L. The UV–Vis spectrophotometric method validated the ImageJ approach, yielding an R² value of 0.9993 and a detection limit of 0.006253 mg/L. For Cu(II) adsorption, CNF-MSN removed nearly 100 % of Cu(II) within 45 min at pH 4–6, outperforming individual CNF and MSN with an adsorption capacity of 0.0978 mg/g and 97.85 % removal efficiency. In real samples, removal efficiencies ranged from 94.1 % to 99.1 %, with a maximum adsorption capacity of 38.9 mg/g. The adsorption data fit the Dubinin–Radushkevich isotherm (R² = 0.980) and the pseudo-second-order kinetics (R² = 0.999). Overall, the CNF-MSN composite offers a sustainable and efficient material for detecting and remediating Cu(II) in water systems.Item Case Study: Evaluation of stress concentration factors in shaft keyways through FE analysis(2025-09) Jordaan, Johannes PThe finite element method (FEM) is utilised in evaluating stresses in keyways of shafts loaded in torsion. These stress values are divided by their corresponding nominal stresses to arrive at so-called stress concentrationfactors, which are compared against published charts and experimental results for specific reference cases. FEM has become ubiquitous in the analysis and design of mechanical systems. While simple and well-known formulas for analytical solutions are employed to calculate nominal stresses in static design, dynamic or fatigue design is typically concerned with higher-than-nominal stresses that are associated with localised geometric stress raisers present in the system. These higher stresses are derived from nominal stresses by multiplication with an appropriate stress concentration factor. At present, though, the application of a multiplier to a nominal value seems somewhat redundant since the complete stress distribution – which includes the maximum stresses in areas of stress concentration – is a direct result from a finite element analysis (FEA). In this paper it is shown that FEA results not only compare favourably with available known results for commonly encountered stress raisers such as fillets and keyways but provide resolution to the stress distribution and paves the way for analysis and design of mechanical devices exhibiting uncommonly encountered stress raisers for which charts and formulas are not available.Item Synthesis of chitosan-modified poly (lactic-co-glycolic acid) microparticles with pH-dependent controlled-release kinetics to enhance the delivery of potential antidiarrheal medicinal plant extract to the lower gastrointestinal track(2025-12) Shatri, AMN; Lemmer, Yolandy; Kalombo, L; Mandiwana, Vusani; Mumbengegwi, RPhytotherapy has been used to treat gastroenteritis in many African countries, with medicinal plant extracts from Grewia tenax, Corchorus tridens, and Lantana camara showing strong antibacterial properties against bacteria that cause gastroenteritis. However, issues such as uncontrolled metabolism by gastric juices and instability in the gastrointestinal tract due to varying pH levels reduce the effectiveness of these phytomedicines. This has limited their use as an alternative or complementary treatment for gastroenteritis. To address this, nanotechnology has been employed to improve the pharmacokinetic and pharmacodynamic properties of phytomedicines. This study aimed to develop biodegradable, plant-based, chitosan-modified poly(lactic-co-glycolic acid) (CMPLGA) microparticles for targeted release in the lower gastrointestinal tract. Nanoparticles were created by mixing 12. 5 mg/ml of polymers with 120 mg/ml of antibacterial extracts from G. tenax, C. tridens. and L. camara using a modified double emulsion (W 1/O/W 2) and solvent evaporation method. The size and zeta potential of the nanoparticles were measured using photon correlation spectroscopy and electrophoretic laser Doppler anemometry. Scanning Electron Microscopy was used to examine morphology, and the encapsulation efficiency was determined via UV- vis spectroscopy. In vitro, the release kinetics of the plant extracts from the nanoparticles were investigated using sample separation techniques in simulated gastric and intestinal fluids, without the presence of enzymes. The plant-based CMPLGA nanoparticles were spherical, with sizes ranging from 524 ± 18 nm. 92 nm to 2582 ± 123 nm, and zeta potential from 2. 68 ± 0. 08 mV to 44. 2 ± 0. 100 mV; encapsulation efficiency was greater than 89.8 %. The release of phytomedicine from the nanoparticles depended on pH, with <2 % release at pH 1. 2 and over 50 % release at pH 7. 7.4. These CMPLGA nanoparticles improved the stability of the antibacterial phytomedicine in acidic conditions similar to those in the upper GI tract. They may serve as an effective vehicle for future drug delivery targeting gastrointestinal pathogens in the lower GI tract.Item Phenomenological and mechanistic insights into potential dietary nucleotide – probiotic synergies in layer chickens: A review(2025-05) Dibakoane, SR; Mhlongo, G; Moonsamy, Ghaneshree; Wokadala, OC , SR Mhlongo; Mnisi, CM; Mlambo, VDespite their growing popularity as alternatives to antibiotic growth promoters (AGPs), the individual effects of nucleotides and probiotics on poultry gut functionality remain poorly understood. In addition, inconsistent outcomes are quite common in studies where these two additives have been used separately to modify gut function and related parameters in birds. These inconsistencies, which have limited the potential of probiotics and nucleotides as AGP replacements, stem from various factors and need to be addressed. Combining probiotics and nucleotides could potentially enhance their effectiveness and lead to more consistent outcomes in layer chickens. Since their mechanisms of action complement each other, some level of synergy is expected when used together. Both additives have been shown to support gut health, boost immune function, and improve performance in chickens when used individually. However, no studies have investigated the possible synergistic effects of nucleotides and probiotics in poultry. This review makes the case for combined use of probiotics and nucleotides in layer chickens by providing phenomenological and mechanistic insights into hypothetical synergistic effects. This paper highlights the need for AGP alternatives and reviews studies on the effects and mechanisms of probiotics and nucleotides in layer chickens when used individually. We then propose potential mechanisms for their synergistic effects on gut health, performance, and egg quality based on logical deductions from observed biological responses. These proposed mechanisms are hypothetical and require experimental validation. Finally, the review explores how this synergy could lead to more consistent outcomes and enhance the feasibility of AGP-free egg production.