Research Articles (University of Pretoria)

Permanent URI for this collectionhttp://hdl.handle.net/2263/121

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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Synthesis, structural characterization, biological and in silico evaluation of halogenated Schiff bases as potential multifunctional agents
(Elsevier, 2026-02) Nthehang, Tsholofelo S.; Waziri, Ibrahim; Yusuf, Tunde Lewis; Oselusi, Samson Olaitan; Muller, Alfred J
Please read abstract in the article. HIGHLIGHTS • Three new halogen substituted Schiff bases (SB1, SB2, and SB3) were synthesized. • Detailed spectroscopic and theoretical investigations were carried out. • All compounds were tested for cyto-toxicity, antioxidant, and antibacterial. • Biological study results revealed SB1 and SB3 as the most potent across all the assays, with SB1 been more superior.
A MeerKAT study of a neutral hydrogen rich grouping of galaxies with megaparsec-scale filamentary-like structure
(EDP Sciences, 2025-09) Lawrie, G.D.; Deane, Roger; Dave, R.
CONTEXT. Environmental effects within cosmological overdensities, such as galaxy groups and clusters, have been shown to impact galaxies and their cold gas reservoirs and thereby provide constraints on galaxy evolution models. Galaxy groups foster frequent galaxy-galaxy interactions, making them rich environments in which to study galaxy transformation. AIMS. In this work, we study a serendipitously discovered large overdensity of neutral hydrogen (H I) galaxies at z ∼ 0.04. The galaxies appear to lie in a filamentary-like structure of megaparsec scale. Using MeerKAT’s angular resolution and field of view, we were able to spatially resolve the H I galaxies while simultaneously probing large-scale structure. METHODS. The H I and sub-arcsec Dark Energy Survey (DES) imaging have revealed a large number of both interacting and disturbed galaxies in this collective group. MeerKAT data enabled us to derive H I masses and investigate interacting galaxies. We used DES and Wide-field Infrared Survey Explorer (WISE) data to quantify the star formation rates, stellar masses, and stellar morphologies of member galaxies and compared these with field scaling relations. To place this discovery and the environmental effects in context, we used the SIMBA cosmological hydrodynamical simulation to investigate the prevalence of qualitatively similar H I overdensities and their large-scale morphological properties. This enabled us to make a prediction of how frequently such structures might be serendipitously discovered with MeerKAT and SKA-Mid H I observations in comparable observation time. RESULTS. The combination of spatially resolved H I data and optical imaging revealed a group rich in interactions, suggesting environmental processes are already shaping galaxy properties within the structure. CONCLUSIONS. More of these serendipitous discoveries are expected, and alongside ongoing targeted programmes, they will provide a rich, unbiased sample to study galaxy transformation and enable a MeerKAT H I perspective on large-scale structure, including filaments.
Sensitivity of the endwall flow in a linear vane cascade to blade fillet geometry
(Elsevier, 2025-09) Shote, Adeola Suhud; Mahmood, Gazi; u14145295@tuks.co.za
Based on the blade chord and inlet velocity, the current computational study uses a linear vane cascade with a large filleted blade-endwall junction with a 2.01 x 105 Reynolds number. Three fillets with related profiles are explored. To evaluate the upshots of geometric differences in a fillet attached to the endwall flow-field, the height and endwall-width of the fillets are changed. The RANS k-ω turbulent model is used in the computations, and the results are compared to experimental results from a similar cascade without the fillet. The computed results of the secondary flow-field in the endwall region along the cascade are compared for baseline (no fillet) and filleted passages. As a result of diminished leading-edge and passage vortices, the fillets lower pitchwise pressure gradients, flow separation, axial vorticity, and overall pressure losses when compared to the baseline. The pros of fillets on endwall secondary flows are however unaffected by fillet's geometric changes.
Electropolymerization of polyaniline on coated activated carbon derived from human hair as a bilayer electrode for supercapacitor applications
(Elsevier, 2025-09) Adam, Rashed Ali Mohamed; Maphiri, Vusani Muswa; Otun, Kabir Opeyemi; Fasakin, Oladepo; Rutavi, Gift; Thior, Souleymane; Manyala, Ncholu I.; Maphiri, Vusani Muswa; Maphiri, Vusani Muswa; Otun, Kabir Opeyemi; Otun, Kabir Opeyemi; Maphiri, Vusani Muswa; Otun, Kabir Opeyemi; Fasakin, Oladepo; Rutavi, Gift; Thior, Souleymane
In this study, electropolymerization was used to deposit polyaniline (PANI) layer on the surface of coated activated carbon derived from human hair (HH-AC) using nickel foam as conducting substrate via cyclic voltammetry (CV) at different cycle numbers. The bilayer HH-AC/PANI electrode was prepared in a non-acidic medium unlike other conventional electrochemical polymerization methods, and characterized using Raman spectroscopy, UV–visible spectroscopy, scanning electron microscope (SEM), and nitrogen physisorption measurements to determine the chemical composition, electronic structure, surface morphology, and textural properties, respectively. The results showed that a PANI layer was successfully deposited on the surface of HH-AC. The electrochemical evaluation was carried out using CV, galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques in 2.5 M KNO3 neutral electrolyte. The optimal bilayer electrode prepared by 8-cycles and denoted as HH-AC/PANI-8 shows an excellent specific capacitance of 220 F g−1 at a positive potential, which is almost twice of 121 F g−1 for that of pristine HH-AC operated in a three-electrode system. Furthermore, for practical application, a symmetric device comprising HH-AC/PANI-8 bilayer electrode was assembled and tested in a two-electrode system configuration, leading to a specific energy of 28.6 W h kg−1 and a specific power of 800W kg−1, at a specific current of 1 A g−1 and voltage window of 1.6 V. Besides, the capacitance retention of the device remained 83 % after 10,000 cycles at 5 A g−1, indicating a long lifespan. These results suggest that the HH-AC/PANI-8 bilayer electrode is a promising candidate for high-performance supercapacitors.
Applications of graphitic carbonaceous materials in photosupercapacitors : recent breakthroughs and future perspectives
(Elsevier, 2025-10) Mombeshora, Edwin Tonderai; Muchuweni, Edigar; Ndungu, Patrick Gathura; et.mombeshora@up.ac.za
Photosupercapacitors (PSCs) have recently attracted extensive research interest as one of the most promising energy storage devices owing to their self-charging attributes, small sizes, portability, lightweight, and ability to support emerging wearable electronics. With the recent emergence of high-specific energy density (Es) applications, including powering hybrid and electric vehicles, noteworthy research efforts are centred on increasing electrochemical performance, cost-effectiveness, and cycle lifespan of PSCs. This is being pursued by developing low-cost electrode materials with high reversible capacity and Es. One potential route to advancements in PSCs is turning to graphitic carbonaceous materials as promising electrode materials. Graphitic carbonaceous materials can be favourably derived from waste biomass, offer tailorable porosity and electro-active area, promote exciton dissociation during PSC charging by acting as electron transport layers, function dually as counter electrodes in solar cells and as electrodes in SCs, and are compatible with binder-free designs, among other merits. Therefore, this review focuses on the current understanding of the shortfalls and merits of using graphitic carbonaceous materials in PSCs. It also highlights the challenges and provides recommendations for improvement regarding PSC design, electrolyte selection, material compatibility, binder usage, fabrication processes, characterisation protocols, and components. Finally, the merits, demerits, and prospects of employing graphitic carbonaceous materials to advance PSC sustainability and performance are outlined.
The incidence of electrocardiographic (ECG) changes suggestive of myocardial infarction in patients attending Kalafong Provincial Tertiary Hospital diabetes clinic
(Medpharm Publications, 2025-09) Xhekwani, Boneswa N.; De Villiers, Maryke; Van Zyl, Danie G.
AIMS: This study aims to determine the incidence of new electrocardiographic (ECG) changes suggestive of myocardial infarction (MI) in diabetic patients, both with and without typical symptoms. Additionally, it seeks to identify other ECG abnormalities indicative of the effects of diabetes mellitus (DM) on the heart. METHODS : Patients aged 30 years and older were selected from the DM clinic database covering the period from 2008 to 2023. A total of 732 patients were initially identified, of whom 634 were eligible for inclusion in the study. A subgroup of 568 patients had normal baseline ECGs. ECG abnormalities were reviewed and discussed with the senior physician, with findings documented in the electronic database. Two ECGs, at least one year apart, were compared. In patients with more than two ECGs, the first one with abnormal findings was compared with the baseline ECG. Kaplan–Meier analyses were performed to assess the time to new ischaemia and MI in patients without baseline ECG abnormalities comparing patients with Type 1 and Type 2 DM (hazard ratio [HR] 2.082, 95% confidence interval [CI] 1.049–4.133). RESULTS : Of the patients eligible for the study, 83% (n = 568) had normal ECGs at baseline. Among them, 33.1% (n = 210) developed ECG abnormalities at follow-up. Ninety-seven patients (15.3%) showed ECG signs suggestive of myocardial infarction/ischaemia, with 66 (16.7%) females and 31 (13%) males exhibiting these changes. The most common myocardial regions affected were the inferior wall, followed by the inferolateral wall, while the anterior wall was the least commonly affected. Type 2 DM patients exhibited a higher incidence of ECG changes suggestive of MI compared with those with Type 1 DM (16.7% vs. 9.8%). Other common ECG abnormalities included atrioventricular (AV) conduction defects (right and left bundle branch blocks, first-degree AV block), P-wave abnormalities (P mitrale), increased incidence of left ventricular hypertrophy (LVH), and poor R wave progression. CONCLUSIONS : A higher incidence of myocardial ischaemia and other ECG abnormalities were observed in diabetic patients, particularly those with Type 2 DM.
Interrogating the role of contextual intelligence when applying professional discretion by South African public-school principals
(University of Venda, 2025-06) Beyers-Prinsloo, René; Du Plessis, A. (Andre); rene.beyers@up.ac.za
This research, rooted in the contextual intelligence theory, aimed to investigate how contextual intelligence influences the capacity of public-school principals to exercise professional discretion. The research delved into the decision-making processes of principals when confronted with challenging decisions related to legislation, policy, leadership, and management within the distinctive operational context of their schools. Utilising pragmatism as a paradigm, this was a mixed-methods study during which survey questionnaires and semi-structured interviews were the data collection techniques. The findings revealed that principals frequently encounter context-specific scenarios that require contextual intelligence to appropriately apply professional discretion in their decision-making. In prioritising the well-being of learners and staff, principals often find themselves compelled to deviate from official policies that fail to consider the contextual nuances of their schools. The study used an explanatory sequential mixed-methods design. Findings from the quantitative phase during which a survey was used, informed the semi-structured interviews in the qualitative data collection phase. Probability and non-probability sampling techniques were respectively applied in the quantitative and qualitative phases of the study. Quantitative data was analysed using Google Forms and descriptive statistics. In the qualitative phase, thematic analysis was conducted using Atlas. Ti software, allowing for detailed exploration and elaboration of the quantitative results.
Causal links between public debt and inflation in sub-Saharan African countries
(Elsevier, 2025-11-25) Aimola, Akingbade U.; Monkam, Nara F.; akingbade.aimola@up.ac.za
This study aims to investigate and compare both symmetric and asymmetric causal relationships between public debt and inflation across a panel of 14 sub-Saharan African countries over the period 1990 to 2021. It also examines trends in Country Policy and Institutional Assessment (CPIA) scores, particularly in the domains of debt policy and the efficiency of revenue mobilization. The analysis employs Konya's (2006) symmetric bootstrap panel causality test and an asymmetric approach developed by Yılancı and Aydın (2017), which builds on Granger and Yoon (2002) and Konya's methodology. The results reveal notable nonlinearity and considerable cross-country variation. Under the symmetric specification, causality from public debt to inflation is found in only four countries. However, when asymmetry is incorporated, this number increases to twelve. Similarly, while causality from inflation to debt is observed in four countries using the symmetric model, the asymmetric framework reveals evidence in eleven countries. These findings contribute to literature by offering a comparative perspective on the debt-inflation nexus. Moreover, the results indicate the presence of cross-sectional dependence across the panel and confirm country-specific heterogeneity. The analysis of CPIA indicators also points to varied levels of institutional capacity in public debt management and revenue mobilization across the region. Notably, Kenya's top performance in revenue mobilisation suggests that robust institutional frameworks can enhance the predictive relationship between increase public debt levels and inflation. The study's findings carry significant implications for fiscal and monetary policy in sub-Saharan Africa.
John Chrysostom’s Interpretation of the Book of Ruth in His Homilies on the Gospel of Matthew
(Taylor and Francis, 2024-03-25) De Wet, Chris Len; chris.dewet@up.ac.za
This article examines John Chrysostom’s interpretation of Ruth, highlighting how he frames her as a marginal yet important figure within the late antique Christian discourse on gender, power, and ethnicity. While Chrysostom is often labelled a literalist interpreter, his reading of Ruth demonstrates a complex figurative and typological approach that aligns her with the church while associating figures like Tamar and Rahab with the synagogue. This figurative reading serves both a polemical and pedagogical function, reinforcing his broader anti-Jewish rhetoric while using Ruth’s foreignness and poverty to model Christian identity. Ironically, Chrysostom presents Ruth as an emblem of the church, despite her historical choice to embrace Judaism, showing the adaptability of biblical figures in Christian exegesis. By exploring how Chrysostom employs gendered and ethnic tropes, this article sheds light on the exegetical strategies that shaped Christian identity formation and biblical interpretation in the fourth century.
Exploring the pedagogical value of game design for landscape architects
(Wichmann Verlag, 2025) Bartelse, Gabrielle; Steyn, Raita
This study forms part of the ongoing project entitled THEATRUM conducted by Gabrielle Bartelse, which explores the pedagogical value of game design in landscape architecture, emphasising the role of virtual landscapes as educational tools. By applying game design principles such as narrative, immersion and flow, the paper investigates how Open-World Video Games (OWVG) can support landscape architects in developing design and research skills. Furthermore, in the framework of the THEATRUM project’s aims, Mór Grommers (2022) proposes in his Bachelor Thesis six core functions of landscapes namely creating atmosphere, storytelling, providing consistency, integrating with objectives and puzzles, offering topographic guidance, and implementing gating mechanisms. Grommers’s original research establishes a strong foundation for further interdisciplinary studies. Employing a mixed-methods approach, combining literature review, theoretical synthesis, and empirical data from a survey of 204 gamers, the study examines how the above mentioned functions align with the motivations of different player types, such as Killers, Achievers, Socialisers, and Explorers, as defined by Bartle’s taxonomy. Findings reveal that detailed landscapes, freedom of exploration, and narrative elements are critical for promoting immersion. These insights offer valuable guidance for integrating game design principles into landscape architecture education, mainly through innovative technologies such as VR and AR. The study also highlights the importance of collaboration between game designers and landscape architects to create virtual environments that are experimental, functional, and visually compelling. Such environments can serve as platforms for creative exploration, participatory design, and experiential learning, giving landscape architecture students giving landscape architecture students a deeper understanding of the dynamic interactions between humans and landscapes.
Global challenges, local responses : exploring curriculum reform in South African engineering education
(Wiley, 2025-07) Wolff, Karin; Hattingh, Teresa; Smith, Lelanie
BACKGROUND AND AIM : There have been significant higher education curriculum reform initiatives over the past 30 years across different global regions in response to a range of drivers such as employability, global citizenship, and sustainability. In professions such as engineering, a key focus has been on holistic graduate attribute development for scarce skills needs in increasingly complex socio-technical sectors. This paper sets out to explore the drivers of engineering curriculum reform in higher education institutions (HEIs) in a Global South context. DESIGN/METHOD : Drawing on semi-structured, recorded focus group inter-views with 28 program coordinators and academics across 15 of the 16 HEIs offering engineering qualifications in South Africa, the research team set out to determine what kinds of curriculum reform initiatives were being under-taken, who was responsible for initiating, implementing, and supporting these initiatives, and what were perceived to be challenges and successes. The emergent drivers were framed in relation to curriculum responsiveness theory analyzed using an overarching “critical realist” framework with structure, culture, and agency dimensions that systemically influence how curriculum reform is constrained or enabled. RESULTS : The findings reveal both internal and external drivers that align with economic, institutional, and pedagogical responsiveness. The dominance of some levers over others is influenced by the underlying structural and cultural dimensions that affect agency. While some institutions show agency in curriculum reform, the dominant structure–culture dynamic often constrains innovation and maintains the status quo. CONCLUSION : The structure–culture–agency relationships that are presented high-light factors that constrain or enable curriculum reform, which has implications for practice and policy. To drive meaningful and sustainable reform, policymakers must develop frameworks that incentivize not only compliance with accreditation standards but also pedagogical innovation and social responsiveness, ensuring that curriculum transformation aligns with both economic demands and societal needs.
Investigating the use of sugar alcohol as an alternative non-toxic binder to conventional coal tar/coal tar pitch for use in taphole clay
(Göller Verlag, 2025-09) Cameron, Izak Jian-Pierre; Garbers-Craig, Andrie Mariana
Currently, the main purpose for obtaining alternative binders for use in taphole clay is to reduce the exposure to harmful polycyclic aromatic hydrocarbons (PAH) associated with conventional coal tar (CTht) binders. Some advances have been made such as using lower-PAH alternative binders or phenolic resole resins (resin-bonded) in taphole clays. The use of non-toxic binders has become exceedingly difficult due to the versatility of CTht in taphole clay. This study investigated a combination binder system that consisted of a sugar alcohol (research-grade glycerine) and phenolic resole resin as a potential non-toxic binder for use in platinum smelting taphole clay. The binder system was characterized according to its composition by means of Fourier-transform infrared spectroscopy and the PAH content (16-EPA-PAH) was determined using targeted gas chromatography mass spectroscopy. Flow behaviour of the binder was determined based on rotational rheology, and the volatilization and rheological thermal stability of the binders were assessed by means of thermogravimetric analysis and thermorheology, respectively. The effect of mixing these binder constituents on the cross-linking behaviour of the phenolic resin was evaluated using differential scanning calorimetry. The combination binder had a higher average mass loss and lower carbon yield compared to conventional CTht, but with a lower total PAH content, making it a more health-friendly alternative.
Advancing cervical cancer treatment : integrating cannabinoids, combination therapies and nanotechnology
(Springer, 2025-10) Mathibela, Sanele Priscilla; Ncube, Keith Ntokozo; Lebelo, Maphuti Tebogo; Steenkamp, Vanessa; vanessa.steenkamp@up.ac.za
BACKGROUND : Cervical cancer remains a major global health challenge, with the highest incidence and mortality rates observed in sub-Saharan Africa. Despite progress in prevention and treatment, the management of advanced and recurrent disease remains difficult. AIM : This review explores the potential role of cannabinoids in cervical cancer therapy, with a focus on their integration into existing treatment strategies, combination therapies, and nanotechnology-based delivery systems. METHODS : A critical synthesis of preclinical studies and emerging therapeutic approaches was conducted, examining the anticancer properties of cannabinoids, their mechanisms of action, and their application within combination and nanotechnology-based treatment modalities. RESULTS : Cannabinoids such as tetrahydrocannabinol (THC) and cannabidiol (CBD) demonstrate anticancer effects by inducing apoptosis, inhibiting cell proliferation, and suppressing metastasis. Mechanistic studies highlight their ability to promote oxidative stress, modulate key signalling pathways, and influence immune responses in cervical cancer cells. Combination therapies involving cannabinoids with chemotherapy, radiotherapy, and immunotherapy show enhanced efficacy and reduced drug resistance. Furthermore, nanotechnology-based delivery systems offer advantages including targeted drug release, improved solubility, controlled dosing, and decreased systemic toxicity. CONCLUSION : Cannabinoids represent a promising adjunct in cervical cancer management. However, successful clinical translation requires optimisation of formulations, establishment of dosing protocols, and comprehensive safety evaluation. Future research should also explore biomarker-driven personalised medicine approaches. Standardisation, along with addressing regulatory and ethical challenges, will be crucial for the integration of cannabinoid-based therapies into mainstream cervical cancer treatment.
Conscientious corporate brands : the roles of organisational purpose, organisational culture, brand authenticity and corporate social responsibility
(Palgrave Macmillan, 2025-09) Abratt, Russell; Quaye, Emmanuel Silva; Kleyn, Nicola Susan; kleynn@gibs.co.za
The Conscientious corporate brand (CCB) is a nascent concept whose importance has grown in recent years due to stakeholder demands for organisations to address environmental and social changes as well as to display ethical behaviour in business dealings. Amidst calls for the identification and validation of the antecedents and mediators of CCBs, the purpose of this paper is to establish the role organisational purpose, ethical organisational culture, CSR and brand authenticity plays in shaping stakeholder perceptions of a CCB. Two studies were conducted, using samples obtained from Prolific. In study 1, the results show that organisational purpose is a powerful concept that positively influences the perception of a strong CCB by stakeholders, and that organisational culture moderates the relationship between organisational purpose and brand authenticity. In study 2, our results show that brand authenticity mediates the link between organisational purpose and stakeholder perceptions of a CCB and our findings also suggest that corporate brands with a strong organisational purpose are more likely to be perceived by stakeholders to be a CCB. The theoretical and managerial implications of these findings are discussed, and recommendations for future research are suggested.
Professional skepticism and behavioral bias in financial professionals
(Elsevier, 2025-09) De Klerk, Charisa; Enslin, Zack; Hall, J.H. (John Henry); charisa.deklerk@up.ac.za
Over the past few years professional skepticism has received attention from various stakeholders such as policymakers, practitioners, regulators, and the public. The interest was driven by financial professionals’ failure to apply professional skepticism and the damage it has caused the reputation of the accounting profession. This study investigates the relationship between professional skepticism as a trait and decision-making biases, while also exploring how factors such as gender, age, experience, and personality traits influence financial professionals’ susceptibility to decision-making biases. The study adopted an advanced statistical technique using structural equation modelling to explore the relationship between professional skepticism and decision-making biases. Online surveys were distributed and completed by professional accountants who have professional accreditation with the International Auditing and Assurance Board (IAASB). Findings revealed the presence to a significant extent among financial professionals of confirmation bias, misconceptions of regression to the mean bias, conjunctive event bias, overconfidence bias, and affect bias. Further findings reveal that specific constructs within the professional skepticism trait such as questioning mind, suspension of judgement, search for knowledge, and self-determining, show significant positive (and in some instances negative) relationships with decision-making biases. Gender, experience, and personality traits (such as extraversion and neuroticism) were found to influence susceptibility to certain biases. This research contributes to literature, offering insights into the relationship between professional skepticism and decision-making biases, underlining the importance of understanding skepticism’s implications for decision-makers. HIGHLIGHTS • Relationship between professional skepticism and bias in decision-making identified. • Using SEM to measure relationships between professional skepticism and decision-making biases. • Unpacking professional trait skepticism constructs.
Bark and ambrosia beetle communities (Coleoptera: Curculionidae: Scolytinae: Platypodinae) across five mangrove forests in South Africa
(SpringerOpen, 2025-06) Osorio, Jhon Alexander; Chara, Jenny
BACKGROUND : Mangrove forests are of fundamental significance that support a diverse array of species, but despite their importance and the benefits they provide, the health of these trees is under constant threat. This is due to a variety of environmental and human factors, which lead to their weakening and susceptibility to colonization by insect pests. Although the diversity of bark and ambrosia beetles has been well documented worldwide, there is limited information available regarding their relationships with mangroves. To investigate the diversity and distribution of ambrosia and bark beetles associated with mangrove habitats in South Africa, extensive field surveys and species sampling across various mangrove sites were carried out, as well as Lindgren and Panel traps were installed along five estuaries in KwaZulu–Natal and one in the Eastern Cape Province, from October to December 2013 and January to February 2014. RESULTS : A total of 8677 individuals comprising 11 genera and 16 species of ambrosia and bark beetles were captured. Of these, the most abundant was Hypothenemus eruditus (n = 2178; 25.10%), followed by Ambrosiodmus natalensis (n = 863; 10.36%), Xyleborus affinis (n = 844; 9,73%) and Premnobius cavipennis (n = 833; 9,60%), respectively. The remaining species registered an incidence lower than 7%. From the analysis of representativeness by rarefaction curves, there was no trend toward an increase in species as the number of trajectories increased. CONCLUSIONS : This research contributes to understanding the biodiversity of ambrosia and bark beetle assemblages within South African mangrove ecosystems and underscores the importance of conserving these habitats in the face of environmental and anthropogenic pressures. The findings provide a valuable baseline for future studies and management strategies aimed at preserving mangrove health and monitoring beetle community dynamics in these critical coastal environments.
Symptoms of ADHD and other common mental disorders influence academic success in South African undergraduates
(Sage, 2025-03) Mohamad, Nawal; Rousseau, Kim-Louise; Dowlut, Fatimah; Gering, Milton; Thomas, Kevin G.F.
OBJECTIVE : ADHD symptoms are highly prevalent among university students. These symptoms, particularly the inattentive cluster, predispose students to poorer academic performance and worse academic adjustment. Moreover, ADHD symptoms are often comorbid with other common mental disorders; this comorbidity also leads to poor outcomes. South African students often have fewer resources to successfully transition to university. Hence, our longitudinal study used data from a sample of South African first-year undergraduate students to investigate (a) associations between ADHD symptoms and academic performance/adjustment, (b) separate influences of the inattentive and hyperactivity-impulsivity clusters on academic performance/adjustment, and (c) the influence of the combination of ADHD and psychiatric comorbidities on academic performance/adjustment. METHOD : We collected data three times through the first semester of 2023. Predictors within our regression models included sociodemographic variables, psychological variables (self-reported symptoms of ADHD, depression, anxiety, and risky alcohol use), and high school academic performance. Outcomes were first-semester GPA and self-reported academic adjustment (magnitude of change across the semester and overall adjustment at the end of the semester). RESULTS : Analyses showed that, unlike academic performance (N = 506), magnitude of change in academic adjustment (N = 180) was significantly predicted by ADHD symptoms and the combination of ADHD (p = .02), depression (p < .001), and anxiety symptoms (p = .01). Inattentive ADHD symptoms predicted both academic performance and magnitude of change in academic adjustment. CONCLUSIONS : Our findings suggest that the presence of ADHD symptoms (both with and without other common mental disorders) is associated with a smaller magnitude of academic adjustment, and that the presence of inattentive symptoms of ADHD is associated with both poorer academic performance and smaller magnitude of academic adjustment. These findings are significant in informing future interventions targeting the academic outcomes of first-year university students.
Coordination complexes of N-((4-pyridyl)methyl)-1,8-naphthalimide and divalent metal halides : structures and solid-state fluorescence
(Taylor and Francis, 2025) Beebeejaun-Boodoo, B.M. Parveen; Rademeyer, Melanie; parveen.beebeejaun@up.ac.za
Please read abstract in the article.
Uncertainty avoidance, perceptions of emergency remote education, and university commitment : a cross-country analysis
(Routledge, 2025) Donohue, Dana K.; Bornman, Juan; Osborne, Randall; Tidikis, Viktoria; Buzdar, Muhammad Ayub; Graham, Marien Alet
Worldwide, there were significant changes in university courses due to COVID-19. One was a rapid transition to online courses, described as emergency remote education. The purpose of this research was to examine how students’ uncertainty avoidance (UA) affected their university commitment (UC) and whether their perceptions of emergency remote education (PERE) mediated this relationship. The b path of the mediation analysis (from PERE to commitment) was expected to be moderated by two variables: income and perceived quality of instruction. Students from universities in three countries (i.e., the United States (US), Pakistan, and South Africa (SA)) were assessed. The findings revealed that there were direct and indirect effects for this relationship for students from Pakistan, with a partial moderated mediation effect of perceived quality of instruction for students from Pakistan. Positive main effects of UA on UC were found for students from the United States, Pakistan,
Whole genome characterization of Listeria welshimeri isolates recovered from cattle abattoirs and retailers in Gauteng province in South Africa
(Springer, 2025-06) Gana, James; Pierneef, Rian Ewald; Gcebe, Nomakorinte; Moerane, Rebone; Adesiyun, Abiodun Adewale; abiodun.adesiyun@up.ac.za
The study used whole-genome sequencing (WGS) to characterize 12 isolates of L. welshimeri recovered from the beef production chain in Gauteng province, South Africa. Two sequence types (STs) were identified, with ST3294 accounting for 75% (9/12) and ST1084 for 16.7% (2/12) of the isolates. Antimicrobial resistance (AMR) plasmids detected included conjugative plasmid (MOBP2; T_virB11; virb4) in 58.3% and AMR plasmid (NFO33156) in 41.7% of the isolates. Two AMR genes, fosX (25%) and vga (G) (100%), along with 11 virulence factors, were present in all 12 isolates of L. welshimeri. The phylogenomic tree of L. welshimeri clustering based on the ST according to the source, type, and class of beef and beef products revealed three groups: ST3294 (n = 9), ST1084 (n = 2), and unassigned ST (n = 1). The findings of this study demonstrate the potential for transferring genetic materials from non-pathogenic L. welshimeri to pathogenic L. monocytogenes within the same ecological niche.

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