Research Articles (University of Pretoria)

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This collection offers open access to the full text of research articles published by staff, students and affiliates of the University of Pretoria. These items are identical in content to their published counterparts. It is linked to the Research Information System and complements the Annual Research Report.

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Facilitators and barriers to antiretroviral therapy adherence among adolescents and young adults in Sub-Saharan Africa : a scoping review
(MDPI, 2025-06) Moyo, Enos; Moyo, Perseverance; Mangwana, Hadrian; Murewanhema, Grant; Dzinamarira, Tafadzwa
BACKGROUND : Globally, approximately 65% of adolescents undergoing antiretroviral therapy (ART) adhered to their treatment, whereas only 55% achieved viral suppression in 2023. The low rate of viral suppression is concerning, as elevated viral loads are associated with a heightened risk of opportunistic infections, progression to advanced HIV disease, increased mortality, and greater HIV transmission rates. We conducted this scoping review to identify the facilitators and barriers to ART adherence among adolescents and young adults (AYAs) in sub-Saharan Africa (SSA). METHODS : We conducted this scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) checklist. We searched for peer-reviewed articles published in English from 2014 to 2024 across the SCOPUS, ScienceDirect, PubMed, Africa Journals Online, and Google Scholar databases. Two reviewers independently selected the articles and extracted the data. We used NVivo to develop codes and categories of facilitators and barriers. RESULTS : We used 30 articles reporting on studies conducted in 13 countries in this review. The total number of participants in the studies was 12,250. Sixteen articles reported on qualitative studies, nine on quantitative studies, and five on mixed-methods studies. This scoping review identified various personal (14 articles), interpersonal and social (15 articles), healthcare system-related (9 articles), medication-related (7 articles), and economic (2 articles) factors that facilitate ART adherence among AYAs. Additionally, the scoping review also identified various personal (28 articles), interpersonal and social (13 articles), healthcare system-related (14 articles), medication-related (20 articles), school- or work-related (6 articles), and economic (14 articles) factors that hinder ART adherence among AYAs. CONCLUSIONS : Enhancing ART adherence in AYAs requires multiple strategies, including the reduction of internalized stigma, implementation of community awareness campaigns, harm reduction approaches for AYAs who misuse substances, comprehensive education on HIV, and the provision of support from school staff and leadership, alongside the adoption of differentiated service delivery (DSD), which encompasses home-based ART delivery, refills at private pharmacies, community ART distribution centers, and patient-led community ART refill groups, as well as multi-month dispensing practices.
International Consortium on Ageing-Related Pathologies (ICCARP) Audiovestibular Group : fostering international consensus to refine International Classification of Diseases (ICD-11) codes for hearing loss across the life course
(Springer, 2025) Tsimpida, Dialechti; Akeroyd, Michael A.; Bentley, Barry L.; Bhattacharjee, Shuvarthi; Bowl, Michael R.; Broome, Emma; Calimport, Stuart R.G.; Calvert, Sian; Christopher, Gary; Dening, Tom; Di Bonaventura, Silvia; Goswami, Ankita; Gougousis, Spyridon; Govaerts, Paul J.; Gupta, Mini; Henshaw, Helen; Huckstepp, Robert T.R.; Iliadou, Vasiliki Maria; Koutsimani, Theano K.; Lewis, Morag A.; Lin, Frank R.; Miotto, Cecilia Luisa; Nolan, Lisa S.; Nuttall, Helen E.; Onyekere, Chukwuebuka Prince; Phanguphangu, Mukovhe; Plack, Christopher J.; Raghavan, Ramasamy S.; Reed, Nicholas S.; Rova, Konstantina; Steel, Karen P.; Stokroos, Robert J.; Swanepoel, De Wet; Szczepek, Agnieszka J.; Whitney, Susan L.
Following the World Health Organization’s (WHO’s) decision to classify age-related aetiologies, and a global call for action to systematically classify the pathologies of ageing, the International Consortium to Classify Ageing-Related Pathologies (ICCARP) was established in 2023 under the leadership of Cardiff Metropolitan University. Within this consortium, the Audiovestibular Group is actively working to refine the classification of hearing and balance disorders, aligning with the WHO’s commitment to enhance diagnostic frameworks. This effort coincided with the release of the 2025 edition of the International Classification of Diseases 11th Revision (ICD-11) on 14th February 2025.
Global health development aid initiatives and the quality of medical laboratory services in sub-Saharan : a narrative review
(Elsevier, 2025) Musuka, Hazel; Mano, Oscar; Iradukunda, Patrick Gad; Pierre, Gashema; Munyonho, Ferris Tatenda; Moyo, Enos; Dzinamarira, Tafadzwa
BACKGROUND : Medical laboratory diagnostic services play a critical role in the diagnosis, treatment, and management of diseases, forming the cornerstone of effective healthcare systems. Despite the crucial role of laboratory services, the quality and accessibility of medical laboratory services in sub-Saharan (SSA) face significant challenges. Global health development aid has been pivotal in supporting SSA laboratory services. This study aimed to examine global health development aid initiatives that have successfully enhanced the quality of medical laboratory services and the challenges and barriers to effectively improving medical laboratory services through global health development aid in SSA. METHODS : We used a narrative review study design. We searched PubMed, Web of Science and Scopus for articles published in the last 15 years. These three databases are generally considered premier databases for peer-reviewed articles in global health, public health, health systems, and biomedical sciences. The inclusion criteria for this review included research studies, reports, and grey literature. Only articles published in English from 2010 onward were considered. The analysis followed a qualitative approach, emphasizing thematic synthesis and critical interpretation. RESULTS : Forty articles were included in this study. Of these, 18 were primary research studies, 11 were reports, 7 were commentaries, and 4 were reviews. Five sub-themes from the successful global health development aid initiative themes were capacity building and training programs, infrastructure development, partnership models, policy advocacy and regulatory support, quality control and standardization of laboratory services. The sub-themes from the challenges and barrier theme were insufficient funding and resource allocation, human resource constraints, inadequate infrastructure and equipment, and political and institutional barriers. This review revealed that several factors, including financial sustainability, human resource capacity, institutional support, resilience, and effective monitoring systems, shape the sustainability of improvements in medical laboratory services in SSA. CONCLUSION : Achieving long-term sustainability requires strategies that ensure financial self-sufficiency, foster a skilled and stable workforce, and integrate laboratory services into national health frameworks.
Entomopathogenic nematodes : commercial use and future perspectives
(Elsevier, 2025-09) Ramakuwela, Tshimangadzo; Tarasco, Eustachio; Chavarría-Hernández, Norberto; Toepfer, Stefan; tshimangadzo.ramakuwela@up.ac.za
The 100 years of research, development, commercialization and use of entomopathogenic nematodes (EPN) since their discovery in the 1920s have seen impressive progress. Nowadays, many EPN products, based on a relatively limited number of EPN species, are commercially available in most world regions. This paper presents a review of EPN commercialization and examples of EPN use in field crops such as maize and in agroforestry ecosystems. It demonstrates how EPN have become an important tool in biological control of insect pests offering many advantages over chemicals. These include farmer and consumer safety, minimal damage to natural enemies, no problems with pollinators, and no environmental pollution. All of these attributes are essential for an advanced and sustainable integrated pest management strategy. We explored future potential of commercialization and adoption of EPN-based biocontrol products. The future may lie in several advances: i) The ability to tailor the use of EPN to broad as well as to local agricultural needs. ii) Enhancing their shelf life and efficacy through genetic improvements. iii) Refining application technologies. iv) Improving mass production (including machine learning using production data). v Reducing production and delivery costs, considering EPN as safe agents and therefore reducing registration burdens. Vi) Finally, expanding their use to a larger market such as to new pest species and crops. With continued research and innovation, EPN could become a cornerstone of sustainable pest management strategies in an increasing number of countries.
Revisiting concepts of thermal physiology : understanding feedback and feedforward control, and local temperature regulation
(Wiley, 2025-07) Mitchell, Duncan; Maloney, Shane K.; Snelling, Edward P.; Hetem, Robyn S.; Fuller, Andrea
Most experts agree that the dominant mechanism through which body temperature is regulated, under a thermal challenge, environmental or metabolic, is negative feedback control. However, some consider negative feedback to be too sluggish to account for the rapid speed of response. The impression of sluggishness is based on an assumption that the body temperature that is regulated is a core temperature, whereas we concur with those who have concluded that what is regulated is an integrated temperature compiled from inputs from multiple body parts, including the skin. Negative feedback control is supplemented, though, by feedforward control, which is initiated by cues about the predicted magnitude and timing of the thermal challenge. Feedforward control is anticipatory because it can excite thermo-effectors in advance of the thermal challenge impacting on body temperature. Feedforward control is improved by learning but always is supervised by feedback control. There is disagreement about whether the pro-active excitation of thermo-effectors by temperature receptors in the skin occurs by fast feedback control or by feedforward control. We show that skin temperature receptors can provide physiologically meaningful negative feedback within seconds. Both the feedback and the feedforward regulation of integrated body temperature can be modulated by regulation of the temperature of body parts that have special thermoregulatory needs, notably the scrotum.
Effect of fermentation time and varietal difference on the pasting properties and bread-making ability of cassava starch (Manihot esculenta)
(Wiley, 2024-09) Ndjang, Marie Madeleine Nanga; Klang, Mathilde Julie; Fadimatou, Bebbe; Njapndounke, Bilkissou; Foko, Marius Edith Kouam; Kamdem, Michael Hermann Kengne; Tonga, Jordan Lembe; Mmutlane, Edwin Mpho; Ndinteh, Derek Tantoh; Kayitesi, Eugenie; Zambou, Francois Ngoufack
This research is to investigate the breadmaking ability of three cassava starch varieties (96/1414, TME15, and YARA) grown in Cameroon. To achieve this, starch samples from each variety are collected before and during fermentation to determine chemical, rheological, and bread-making properties. They are analyzed for pH, titratable acidity (TTA), lactic acid (LA), specific volume (SPV), and pasting properties using known method; These parameters are used to perform a principal component analysis (PCA). The morphological characteristics are studied by scanning electron microscope (SEM). Result shows that, there is a decrease in pH (6.21–3.8) with an increase in TTA (0.34–7.05) and LA (0.15–6.46) with fermentation time. In parallel, a decrease of pasting properties and an increase in SPV (1.15–2.82 cm3 g−1) are observed. The PCA surrounds 96/1414 day 30, YARA day 30, and TME15 day 25 α 30 as the best samples, and the SEM shows a superficial degradation of the granules after fermentation. Thus, this study suggests that the optimal sour cassava starch for bread-making can be obtained from 96/1414 day 30, TME15 day 25 α 30, and YARA day 30. The variety 96/1414 appears to have the best bread-making ability while TME15 appears to be most suitable for short fermentation time.
Thermomechanical control of microstructure and precipitation in vanadium microalloyed steel: influence of finish rolling and coiling temperatures
(Wiley, 2024-04) Wu, Zhangqin; Yang, Wen; Tang, Zhenghua; Siyasiya, Charles Witness; Zhang, Jianhua
Six hot compression tests are conducted using the Gleeble3500 thermomechanical simulator to investigate the microstructural evolution and precipitation behavior in low-C–Mn V-microalloyed steel. The specimens are subjected to hot isothermal compression deformation of 87%. The optical microscopy and transmission electron microscopy using carbon extraction replica method are used to characterize the microstructures and precipitation after the simulated thermomechanical controlled process and coiling. The results indicate that increasing the finish rolling temperature benefits the refinement of ferrite grains but has little influence on the refinement of the precipitates. It is also observed that lower coiling temperatures (CTs) promote the formation of fine precipitates. When the CT is 500 °C, the average precipitate size is found to be 86 nm. Furthermore, it is found that the CT significantly influences the nucleation sites of the precipitates inter alia, the matrix, interphase, grain boundaries, and dislocations. As expected, at higher CTs, nucleation is predominantly on the defects rather than the matrix.
Making Miss Diva : idealizing femininity and new embodied nationalism in India
(Routledge, 2024) Roy, Ahonaa
This paper summarizes a narrative-based account of a beauty pageant in India that highlights gender-liminal representations and identities. The title of the pageant – Miss Diva – suggests the internationalization of beauty, body and aesthetics. This essay has three major aims: 1) to reveal the primacy of sexuality over gender that corresponds to gender pluralism and varied gender transgressive politics within the imperative of embodied desires; 2) to discuss the ‘local’ commercial conditions and how gender-liminal subjectivities are patterned within modernity’s commodified cultural representation which is pluralistic in nature; and 3) to envision beauty and representational politics within the vocabulary of the nation-based identity. This paper provides an account of the complex interconnections between the modern nation and its gender(ed) subjectivities, maintaining a balance between global/local standards.
On the precipice of a nuclear-armed Iran and bombing in the name of survival : Whither rule of law?
(Unisa Press, 2024-12) Rossouw, Chrisna; Nienaber McKay, Annelize G.
The inherent right of individual anticipatory self-defence as a response to nuclear proliferation remains unresolved in international law. Following Israel’s attack on Osiraq in 1981, the world community of states deliberated whether the use of force to prevent a state from acquiring a nuclear weapons capability could ever be justified under the purview of the law prohibiting war (jus contra bellum). Without the concept of anticipatory self-defence being clearly defined, threatened states might invoke their inherent right of individual self-defence to ensure, as they see it, their national survival—something contrary to the principles of the UN Charter. As a non-nuclear weapon state prima facie in breach of its obligations under the Nuclear Non-Proliferation Treaty, the Islamic Republic of Iran is alleged to be in pursuit of a nuclear weapons capability. As a response thereto, threatened states are now preparing for a last resort forceful option aimed at curbing Iran’s highly advanced nuclear weapons programme. Yet, the jus contra bellum encompasses good law. As such, the anticipatory use of force against what is believed to be covert Iranian nuclear reactors is illegal. Not only does the United Nations Charter forbid such recourse, so too does the customary right of anticipatory self-defence, justifiably so.
Exploring the digital detox journey among generation Y Instagram users
(Emerald, 2025-07) Scheppe, Matiena Marie; Seiffen, Anna Luise; Berndt, Adele
PURPOSE : Social media (SM) provides a range of positive and negative benefits to users, and an SM detox has been suggested as a way to deal with its negative effects. Instagram (IG) is one of Generation Y’s most widely used SM platforms, noted for its addictive potential. Using a journey perspective, the purpose of this research is to map and describe the experiences in the various stages of a detox journey among Generation Y IG users. DESIGN/METHODOLOGY/APPROACH : Using an inductive and qualitative approach, empirical data were collected over the stages of the journey using focus groups, self-completion diaries and interviews. The data were coded, analysed and interpreted using thematic analysis. FINDINGS : The findings of the study show two main motivations for undertaking a detox, namely gaining back control and self-reformation. During the detox, five themes were identified, specifically mood and satisfaction, technological craving, mental well-being, physical well-being and social relationships. Three post-detox behaviours were noted, namely the boomerang effect, conscious consumption and a re-evaluation towards the platform, which impacts future IG use. RESEARCH LIMITATIONS/IMPLICATIONS : By following one group of participants throughout an IG detox journey, the study highlights the detox experiences in each journey stage. PRACTICAL IMPLICATIONS : The positive benefits of a detox were experienced by the participants, encouraging future detox and actions by platforms to aid in future detoxes. ORIGINALITY/VALUE : This study accompanies one group of participants throughout their detox journey. This enabled the researchers to obtain insights into the detox experience in all phases of the journey. This was undertaken using diverse qualitative methods.
Insights into malaria vectors-plant interaction in a dryland ecosystem
(Nature Research, 2024-09-04) Kinya , Fiona; Milugo, Trizah K.; Mutero , Clifford M.; Wondji, Charles S.; Torto, Baldwyn; Tchouassi, David P.
Improved understanding of mosquito–plant feeding interactions can reveal insights into the ecological dynamics of pathogen transmission. In wild malaria vectors Anopheles gambiae s.l. and An. funestus group surveyed in selected dryland ecosystems of Kenya, we found a low level of plant feeding (2.8%) using biochemical cold anthrone test but uncovered 14-fold (41%) higher rate via DNA barcoding targeting the chloroplast rbcL gene. Plasmodium falciparum positivity was associated with either reduced or increased total sugar levels and varied by mosquito species. Gut analysis revealed the mosquitoes to frequently feed on acacia plants (~ 89%) (mainly Vachellia tortilis) in the family Fabaceae. Chemical analysis revealed 1-octen-3-ol (29.9%) as the dominant mosquito attractant, and the sugars glucose, sucrose, fructose, talose and inositol enriched in the vegetative parts, of acacia plants. Nutritional analysis of An. longipalpis C with high plant feeding rates detected fewer sugars (glucose, talose, fructose) compared to acacia plants. These results demonstrate (i) the sensitivity of DNA barcoding to detect plant feeding in malaria vectors, (ii) Plasmodium infection status affects energetic reserves of wild anopheline vectors and (iii) nutrient content and olfactory cues likely represent potent correlates of acacia preferred as a host plant by diverse malaria vectors. The results have relevance in the development of odor-bait control strategies including attractive targeted sugar-baits.
Improving the antinutritional profiles of common beans (Phaseolus vulgaris L.) moderately impacts carotenoid bioaccessibility but not mineral solubility
(Nature Research, 2024-05-24) Alvarado‑Ramos , Katherine; Bravo‑Nunez , Angela; Halimi , Charlotte; Maillot , Matthieu; Icard‑Verniere, Christele; Forti, Chiara; Preite, Chiara; Ferrari, Luisa; Sala, Tea; Losa, Alessia; Cominelli, Eleonora; Sparvoli, Emanuela Camilli Francesca; Lisciani, Stefania Marconi Silvia; Georgé, Stephane; Mouquet-Rivier, Claire; Kunert, Karl J.
Common beans are a common staple food with valuable nutritional qualities, but their high contents in antinutritional factors (ANFs) can decrease the bioavailability of (i) fat-soluble micronutrients including carotenoids and (ii) minerals. Our objective was to select ANF-poor bean lines that would not interfere with carotenoid and mineral bioavailability. To achieve this objective, seeds of commercial and experimental Phaseolus vulgaris L. bean lines were produced for 2 years and the bean’s content in ANFs (saponins, phytates, tannins, total polyphenols) was assessed. We then measured carotenoid bioaccessibility and mineral solubility (i.e. the fraction of carotenoid and mineral that transfer into the aqueous phase of the digesta and is therefore absorbable) from prepared beans using in vitro digestion. All beans contained at least 200 mg/100 g of saponins and 2.44 mg/100 g tannins. The low phytic acid (lpa) lines, lpa1 and lpa12 exhibited lower phytate levels (≈ − 80%, p = 0.007 and p = 0.02) than their control BAT-93. However, this decrease had no significant impact on mineral solubility. HP5/1 (lpa + phaseolin and lectin PHA-E free) bean line, induced an improvement in carotenoid bioaccessibility (i.e., + 38%, p = 0.02, and + 32%, p = 0.005, for phytofluene bioaccessibility in 2021 and 2022, respectively). We conclude that decrease in the phytate bean content should thus likely be associated to decreases in other ANFs such as tannins or polyphenols to lead to significant improvement of micronutrient bioaccessibility.
Implication of dietary barberry (Berberis Vulgaris) leaves inclusion on growth performance, nutrient digestibility, and carcass traits in ostriches
(Nature Research, 2024-10-20) Afshin, Mojtaba; Afzali, Nazar; Hosseini-Vashan, Seyyed Javad; Hajibabaei, Ali; Ghavipanje, Navid; Vargas-Bello-Perez, Einar
This study determined production performance, nutrient intake, digestibility, and carcass traits from ostrich chicks fed with barberry (Berberis Vulgaris) leaves (BVL) as a replacement for alfalfa hay (AH). For 150 days, 30 male ostrich (Struthio camelus) (9.10 ± 0.89 kg live weight, mean ± SD) were randomly grouped into five dietary BVL inclusion levels to replace AH: a control diet based on 100% AH (CTRL), and four groups with BVL as a substitute for AH at varying levels including 25% (BVL25), 50% (BVL50), 75% (BVL75), and 100% (BVL100). The average daily feed intakes (ADFI) were recorded and birds were weighed monthly. The nutrient intake and digestibility were measured for the following final 5 days of the trial. The ADFI was higher (p = 0.025) for BVL100 and BVL75 than for CTRL. Ostriches fed on BVL50 had the highest average daily gain (ADG, p = 0.025) and the lowest feed conversation ratio (FCR, p = 0.0001). Return per kg BW gain was also enhanced (p = 0.018) with BVL50 feeding. Dietary BVL levels did not affect the digestibility of OM (p = 0.257), CP (p = 0.260), EE (p = 0.610), CF (p = 0.427), and Ash (p = 0.461). Also, there were no changes in AME (p = 0.180) or AMEn (p = 0.670). The hot carcass weight (HCW, p = 0.331) and dressing BW (p = 0.237) were not affected. Overall, the results suggest that BVL can replace AH in ostrich diets without deleterious impact on performance, however, its partial substitution (for 50% AH of diet) has been associated with improved ADG, FCR, and reduced feeding costs.
Factors associated with neonatal sepsis among neonates admitted in Kibungo Referral Hospital, Rwanda
(Nature Research, 2024-07-10) Niyoyita , Jean Claude; Ndayisenga , Jerome; Omolo , Jared; Niyompano , Hosee; Bimenyimana, Pierre Celestin; Dzinamarira, Tafadzwa; Nsekuye , Olivier; Chavez , Isabella; Hakizayezu, Francois
More than one million neonatal deaths occur every year worldwide, of which 99% take place in low-income countries. In Rwanda, nearly 71% of neonatal deaths are preventable and among these, 10% are due to neonatal sepsis. Nevertheless, limited information exists on neonatal sepsis and its associated factors in Rwanda. The objectives of the study were to find prevalence and factors associated with neonatal sepsis among neonates admitted in Kibungo Referral Hospital, Ngoma District, Rwanda. We used a retrospective cross-sectional study design reviewing a subset of neonatal, maternal and laboratory records from Kibungo Hospital in 2017. Data were reviewed and collected from March to May, 2018. Logistic regression and odds ratios were calculated to identify the factors associated with neonatal sepsis at 95% CI, p < 0.05. Of the 972 total neonates’ medical records from 2017, we randomly selected 422 of which 12.8% (n = 54) had neonatal sepsis. When blood cultures were positive, 62% grew Klebsiella pneumoniae. Among neonates with sepsis, 38 (70%) recovered while 16 (30%) died. Neonatal sepsis was strongly associated with neonatal age less than or equal to three days (aOR: 2.769, 95% CI 1.312–5.843; p = 0.008); and gestational age less than 37 weeks (aOR: 4.149; CI 1.1878–9.167; p ≤ 0.001). Increased use of blood cultures including sensitivity testing, routine surface cultures of the neonatology and maternity wards facilities, and systematic ward cleaning are all important approaches to prevent and treat neonatal infections in additional to regular neonatal sepsis evaluations.
Empirical modelling of 2205 DSS flow curves using strain-compensated Arrhenius rate-type constitutive model
(Nature Research, 2024-09-28) Gonya, Elvis M.; Siyasiya, Charles Witness; Makhatha, Mamookho E.
This work predicts, hot flow curves of 2205 DSS using strain-compensated Arrhenius rate-type constitutive model. Twenty-five (25) × Ø10 diameter × 15 mm height cylindrical samples were hot compressed at a temperature between 850 and 1050 °C at an interval of 50 °C and strain rates between 0.001 and 5 s−1, using Gleeble 1500D. After the tests, corrected flow curves were plotted followed by computation of deformations constants at various deformation conditions using steady state stress. The values of the constants were (α = 0.009708, Q = 445 kJ/mol and n = 3.7) and seemed comparable to the previous studies of DSS. Steady state predictive model was then constructed using the calculated constants and showed a reasonably good accuracy with low value of MARE = 7.78%. Furthermore, calculated strain compensated Arrhenius rate type model was used to predict flow curves at various deformation. The model had a good estimation of flow curves of flow curves at 900–1050 °C across all strain rates as reflected by MARE = 5.47%. A notable discrepancy between predicted and experimental flow stress was observed at 850 °C and across all the strain rates. A model refinement using generalised reduced gradient improved the accuracy of the model by 34.7% despite deformation conditions at 850 °C and low strain rates (0.01/ 0.1) s−1 showing minimum improvement. Further modification of Z-parameter by compensating for the strain rate improved the accuracy of the model at 850 °C/0.01 s−1/0.1 s−1. Lastly, a comparison of the current model with the other non-linear model showed that the latter was more accurate in estimation of flow curves since it relied on characteristics flow stress points controlled by underlying active deformation mechanisms.
Elicitation of security threats and vulnerabilities in Insurance chatbots using STRIDE
(Nature Research, 2024-08-02) Bokolo, Zilungile; Daramola, Olawande; wande.daramola@up.ac.za
Although chatbots are used a lot for customer relationship management (CRM), there needs to be more data security and privacy control strategies in chatbots, which has become a security concern for financial services institutions. Chatbots gain access to large amounts of vital company information and clients’ personal information, which makes them a target of security attacks. The loss of data stored in chatbots can cause major harm to companies and customers. In this study, STRIDE (viz. Spoofing, Tampering, Repudiation, Information disclosure, Denial of service, Elevation of privilege) modelling was applied to identify the data security vulnerabilities and threats that pertain to chatbots used in the insurance industry. To do this, we conducted a case study of a South African insurance organisation. The adopted methodology involved data collection from stakeholders in the insurance organisation to identify chatbot use cases and understand chatbot operations. After that, we conducted a STRIDE-based analysis of the chatbot use cases to elicit security threats and vulnerabilities in the insurance chatbots in the organisation. The results reveal that security vulnerabilities associated with Spoofing, Denial of Service, and Elevation of privilege are more relevant to insurance chatbots. The most security threats stem from Tampering, Elevation of privilege, and Spoofing. The study extends the discussion on chatbot security. It fosters an understanding of security threats and vulnerabilities that pertain to insurance chatbots, which is beneficial for security researchers and practitioners working on the security of chatbots and the insurance industry.
Electrocapacitive removal of Na and Cd ions from contaminated aqueous solution using Fe3O4-poly (3,4-ethylenedioxythiophene) poly(styrene sulfonate) modified chitosan nanosheets
(Nature Research, 2024-11-15) Saliu, Oluwaseyi D.; Leping, Omphemetse; Yusuf, Tunde Lewis; Adeniyi, Adewale G.; Ramontja, James
Chitosan nanosheets (NS) stabilized on poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) was functionalized using Fe3O4 to capacitively remove chloride ions and toxic cadmium ions at optimized pH, concentration, and number of charging cycles. The synthesis procedure was investigated by Fourier transform infrared spectroscopy (FTIR), X-Ray Diffractometer (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope – Energy Dispersive X-ray Spectroscopy (SEM-EDS), and Brunauer-Emmett-Teller (BET). The analyses confirms increase in surface area of the nanocomposite from 41 to 132 m2/g and a decrease in crystallinity from 75.3 to 66.9% after nanosheet formation. The highest sorption exchange capacity (SEC) for this work, 93% CdCO3 removal is achieved at 100 CDI cycles while 82% NaCl removal was achieved at 80 cycles. The SEC% increased with pH during Na ion deionization and decreased with pH during Cd removal. The works shows that chitosan is able to impart advanced structural properties to Fe3O4 and PEDOT and is able to reduce reverse migration of ions from electrodes to bulk solution, leading to higher SEC performance.
Investigation of the antimycobacterial activity of African medicinal plants combined with chemometric analysis to identify potential leads
(Nature Research, 2024-06-25) Moyo, Phanankosi; Ofori, Michael; Bodede, Olusola S.; Wooding, Madelien; Khorommbi, Ndivhuwo Kevin; McGaw, Lyndy Joy; Danquah, Cynthia A.; Maharaj, Vinesh J.; vinesh.maharaj@up.ac.za
The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural products drug discovery, which previously led to the discovery of rifamycins, is a valuable approach in this endeavor. Against this backdrop, we set out to investigate the in vitro antimycobacterial properties of medicinal plants from Ghana and South Africa, evaluating 36 extracts and their 252 corresponding solid phase extraction (SPE) generated fractions primarily against the non-pathogenic Mycobacterium smegmatis and Mycobacterium aurum species. The most potent fraction was further evaluated in vitro against infectious M. tuberculosis strain. Crinum asiaticum (bulb) (Amaryllidaceae) emerged as the most potent plant species with specific fractions showing exceptional, near equipotent activity against the non-pathogenic Mycobacterium species (0.39 µg/ml ≤ MIC ≤ 25 µg/ml) with one fraction being moderately active (MIC = 32.6 µg/ml) against M. tuberculosis. Metabolomic analysis led to the identification of eight compounds predicted to be active against M. smegmatis and M. aurum. In conclusion, from our comprehensive study, we generated data which provided an insight into the antimycobacterial properties of Ghanaian and South African plants. Future work will be focused on the isolation and evaluation of the compounds predicted to be active.
Synthesis of an 8-membered oxygen-containing benzo-fused heterocycle using flow technologies - an exercise in undertaking research with sustainability as a driver
(Royal Society of Chemistry, 2025-03) Currie, Bernice Mercia; Neyt-Galetti, Nicole C.; Olivier, Tanya; Van der Merwe, Petra; Dibokwane, Lerato Shirley; Reinhardt, Anshe Michelle; Van Wyk, Lorinda T.; Panayides, Jenny-Lee; Riley, Darren Lyall; darren.riley@up.ac.za
Due 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.
The synthesis and investigation of novel 3-benzoylbenzofurans and pyrazole derivatives for anti-HIV activity
(Royal Society of Chemistry, 2025-05) Khuzwayo, Sinothile S.; Selepe, Mamoalosi A.; Meyer, Debra; Gama, Ntombenhle Hlengiwe
Please read abstract in the article.

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