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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Now showing 1 - 20 of 41653

Recent advances in MXene-based nanocomposites for photocatalytic wastewater treatment, carbon dioxide reduction, and hydrogen production : a comprehensive review
(Elsevier, 2026-02) Masekela, Daniel; Mafa, Potlako J.; Yusuf, Tunde Lewis; Balogun, Sheriff Aweda; Kuvarega, Alex Tawanda; Modibane, Kwena Desmond
Please read abstract in the article.
Genetic and environmental influences on sweet taste liking and related traits : new insights from twin cohorts
(Springer, 2025-09) Armitage, Rhiannon M.; Iatridi, Vasiliki; Gaysina, Darya; Tuorila, Hely; Yeomans, Martin R.; Kaprio, Jaakko; Zellers, Stephanie
Reducing sugar intake is a key component of global health policies and dietary guidelines. However, individuals vary substantially in sweet-liking, commonly characterized by sweet-liking status (extreme sweet-likers, moderate sweet-likers, and sweet-dislikers), yet the heritability of these categories remains unexplored. Monozygotic and dizygotic twins from Finland (FinnTwin12; n = 468; 60% female, aged 21–24) and the UK (TwinsUK; n = 967; 90% female, aged 18–81) rated their liking and perceived intensity of a 20% (w/v) sucrose solution, reported their liking and consumption-frequency of food and beverages and completed additional behavioral, eating and personality measures. We estimated the contribution of additive genetic (A), nonadditive genetic (D), shared (C), and unshared environmental factors (E) in the variance and covariance of sweet-liking (defined ordinally through sweet-liking status and continuously) with related traits to see if they share similar proportions of genetic and environmental factors. Model-fitting indicated 30–48% of the variability in sweet-liking was attributed to (A) additive genetic factors and 52–70% to (E) environmental exposures not shared by siblings. Importantly, such AE models consistently fit best, regardless of sex, cohort, or sweet-liking assessment method. Broadly, correlations between sweet-liking and behavioral, eating, and personality measures were modest (–0.19 to 0.21), mostly positive and largely driven by shared genetic rather than environmental factors, with the strongest relationship seen for reported liking, consumption-frequency and craving for sweet foods. We demonstrate that unshared environment modulates individual differences in sweet-liking alongside a substantial genetic component that is partly shared with reported liking, consumption-frequency and craving for sweet foods.
Spatiotemporal variation of small hive beetle infestation levels in honeybee host colonies
(Springer, 2025-09) Palonen, Aura; Papach, Anna; Muturi, Michael N.K.; Weinstein Teixeira, Erica; Williams, Geoffrey R.; Jacobsen, Rachel; Evans, Jay D.; Posada-Florez, Francisco J.; Pirk, Christian Walter Werner; Lattorff, H. Michael G.; Lawrence, Akinwande K.; Oluseyi, Murele O.; Spooner-Hart, Robert; House, Clarissa M.; Federico, Giovanni; Formato, Giovanni; Neumann, Peter
High infestation levels of small hive beetle (SHB), Aethina tumida, can cause more damage to honeybee, Apis mellifera, host colonies. However, the spatiotemporal variation of SHB infestations is poorly understood. Here, we show that SHB infestations can be equally high in native and invasive ranges, suggesting that differences between host populations are the key criterion for damage. The data reveal that spatial variation within locations was not correlated with migratory beekeeping, SHB management strategies, nor the number of colonies at an apiary. Despite no annual changes in SHB infestations, the data confirm seasonal variation in infestations in two locations probably due to environmental factors affecting SHB. Infestations are lower in Italy than elsewhere, possibly due to strongly implemented management strategies. It is apparent that our understanding of varying SHB infestations is still limited. This suggests that further efforts are required to elucidate our knowledge of this important host-parasite system.
Isolation, characterization, antioxidant and anticancer activities of compounds from Erythrina caffra stem bark extract
(MDPI, 2025-09) Olawale, Femi; Bodede, Olusola; Ariatti, Mario; Singh, Moganavelli
Erythrina caffra is a traditional plant used to treat cancer and inflammation. The study aimed to assess and isolate anticancer compounds from E. caffra bark. The plant material was extracted sequentially in n-hexane, dichloromethane, ethyl acetate and methanol. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and 3-(4,5-di methyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were used to evaluate the crude extracts’ antioxidant and anticancer activities, respectively. Column chromatography was used to purify the potent extracts of the stem bark in order to isolate the bioactive compounds. The crude extracts of the E. caffra bark demonstrated antioxidant and anticancer activity, with the dichloromethane (DCM) extract producing the most favorable activity. Three compounds, namely Hexacosanyl isoferulate, Tetradecyl isoferulate, and 1-Heneicosanol, were detected in fractions from the DCM extract. All the isolated compounds showed significant anticancer potential, with the hydroxycinnamic acid compounds showing better anticancer effects in the cervical (HeLa) and breast cancer (MCF-7) cells. The compounds showed greater activity than even the standard drug, 5-fluorouracil, in the MCF-7 cells, with the tetradecyl isoferulate and hexacosanyl isoferulate fractions having IC50 values of 123.62 and 58.84 µg/mL, respectively. The compounds were observed to be capable of triggering caspase cascade events, leading to apoptotic cell death. Overall, E. caffra extracts contained important bioactive compounds that induced apoptotic cell death in HeLa and MCF-7 tumor cells, warranting further investigations in vitro and in vivo.
Characterizing the quick-killing mechanism of action of azithromycin analogs against malaria parasites
(American Society for Microbiology, 2025-09) Mao, Emma Y.; Nguyen, William; Jana, Gouranga P.; Maity, Bikash C.; Pazicky, Samuel; Giannangelo, Carlo; Reader, Janette; Famodimu, Mufuliat T.; Birkholtz, Lyn-Marie; Delves, Michael J.; Creek, Darren J.; Bozdech, Zbynek; Laleu, Benoit; Burrows, Jeremy N.; Sleebs, Brad E.; Gancheva, Maria R.; Wilson, Danny W.
Drug resistance is steadily undermining the efficacy of frontline anti-malarials, highlighting the urgent need for novel therapies with alternative mechanisms of action. The chemical addition of different moieties to azithromycin yields compounds with improved quick-killing potency against malaria parasites, with the most active analogs typically containing a chloroquinoline group. Here, we investigated the quick-killing mechanism of five azithromycin analogs, two of which contain differentially oriented chloroquinoline moieties. The improvement in quick-killing activity over azithromycin for non-chloroquinoline analogs was around 10 -to 42-fold, with chloroquinoline-containing analogs showing a further 2- to 17-fold improvement over non-chloroquinoline compounds. Chemical inhibition of hemoglobin digestion and chloroquine's inhibitory effect against heme polymerization linked analogs with both chloroquinoline and non-chloroquinoline modifications to a chloroquine-like mechanism of action. However, none of the analogs showed a significant reduction in efficacy against chloroquine-resistant asexual blood-stage parasites. Multiple attempts at selecting for azithromycin analog-resistant parasites to elucidate the mechanism of quick-killing were unsuccessful. Application of cellular thermal shift proteomics revealed that azithromycin analogs significantly stabilized 34-155 different proteins in trophozoites, a high number that showed minimal overlap with chloroquine. Additionally, our most potent chloroquinoline-containing analog demonstrated a significant improvement in gametocytocidal activity over azithromycin and further maintained moderate inhibition of chloroquine-insensitive late-stage gametocytes. These findings support that this class of azithromycin analogs kills malaria parasites through a broad range of potential mechanisms, making them promising candidates for optimization as fast and broad-acting anti-malarials.
The emerging concern of IMP variants being resistant to the only IMP-type metallo-β-lactamase inhibitor, xeruborbactam
(American Society for Microbiology, 2025-07) Le Terrier, Christophe; Drusin, Salvador I.; Nordmann, Patrice; Pitout, Johann D.D.; Peirano, Gisele; Vila, Alejandro J.; Moreno, Diego M.; Poirel, Laurent
Metallo-β-lactamases (MBLs) of IMP type are not inhibited by currently commercialized β-lactamase inhibitors, including taniborbactam (TAN), which inhibits only NDM- and VIM-type enzymes. However, the development of xeruborbactam (XER), which additionally inhibits IMP enzymes, may provide effective drug combinations such as meropenem-XER (MEM-XER) against most MBL producers. Thirty-two IMP-producing clinical gram-negative isolates were tested for MEM-XER. Susceptibility testing of β-lactams with TAN or XER at 4 or 8 µg/mL was performed. Noticeably, MEM-XER remained ineffective against all IMP-producing Pseudomonas aeruginosa isolates. By contrast, supplementation with XER significantly lowered MEM MICs for several IMP-producing Enterobacterales isolates, except for isolates and recombinant E. coli strains producing IMP-6, IMP-10, IMP-14, and IMP-26. Interestingly, IMP-59 producers showed susceptibility to both TAN- and XER-based combinations, although IMP enzymes are not supposed to be inhibited by TAN. Determinations of 50% inhibitory concentration (IC50) values of XER showed values being >15-fold higher for IMP-6, IMP-10, IMP-14, and IMP-26 compared with IMP-1. Interestingly, the IC50 value of TAN for IMP-59 was found in the same range as that for NDM-1 (7 µM). Finally, structural analyses and molecular modeling simulations indicated that the Ser262Gly mutation in IMP-6 may alter the electronic properties of the active site, whereas the Phe residue in IMP-10 may exert a steric effect counteracting XER binding. Resistance to XER in IMP-6, IMP-10, IMP-14, and IMP-26 variants, conferring resistance to MEM-XER, might be considered a serious concern since MEM-XER will be supposed to be a salvage therapy for MBL-, and especially IMP-producing Enterobacterales infections.
Static vs. cidal : it's not complex; it's simply incorrect
(American Society for Microbiology, 2025-08) Spellberg, Brad; Wald-Dickler, Noah; Holtom, Paul; Meyer-Sautter, Pascal; Camp, Austin; Diaz, Alejandro Diaz; Buhamad, Ranya; Vazquez, Ali Sebastian Meza; Aguirre-Garcia, Gloria Mayela; Stanton, Matthew; Butler-Wu, Susan M.; Chiu, Isabelle; Ergenc, Zeynep; Bhoojhawon, Guru; Murri, Rita; Maraolo, Alberto Enrico; Cabanilla, Gabriela; Riccardi, Niccolo; Tshisevhe, Vhudzani; Behenna, Curtis; Williams, Karen S.; Kufel, Wesley D.; Wojciaczyk, Natalia; Pimentel, Bernardo Vidal; Muyidi, Ahmed; Costa, Rodrigo P.L.; Motta, Fabrizio; Bortolussi-Courval, Emilie; Lee, Todd C.; Mcdonald, Emily; Ghanem, Bassam; Nelson, Zachary
No abstract available.
Plant pathogen name game : Cross Kingdom Review for the naming of biotic agents associated with plants
(Annual Reviews, 2025-09) Bull, Carolee T.; Salgado-Salazar, Catalina; Romberg, Megan K.; Allen, Cavan; Kantor, Mihail; Handoo, Zafar; Aboughanem-Sabanadzovic, Nina; Sabanadzovic, Sead; Coutinho, Teresa A.
To communicate across scientific disciplines, regulatory bodies, and the agricultural community, the naming of plant pathogens assigned to specific taxa is critical. Here, we provide an overview of the nomenclatural systems governing the naming of plant-pathogenic nematodes, fungi, oomycetes, prokaryotes, and viruses. Although we focus on the nature of the nomenclatural codes, we briefly discuss fundamental principles of taxonomy, including classification and identification. Key elements of the codes of nomenclature that ensure stability and clarity when naming species of pathogens are defined. When comparing the practice of nomenclature across different kingdoms, the classification and nomenclatural systems differ, and thus unique challenges are faced. We provide guidance from the codes and current practice for naming novel species. When there are nomenclatural conflicts, international committees play a critical role in their resolution. They also play a role in updating the codes to reflect new advancements in science. With this review, we aim to assist plant pathologists, journal editors, and those in related fields by providing an entrée to the legalistic requirements of the codes. Authors must consult and follow the rules of the appropriate code for any proposal of new or new combinations of names. To those interested in naming new species (or renaming the current ones), we recommend collaborations with experts in the field of taxonomy to ensure that rules for accurate and consistent naming practices and procedures are followed and to increase the likelihood that the proposed nomenclature is correct and acceptable.
Cryphonectriaceae : biodiverse and threatening tree pathogens in the tropics and southern hemisphere
(Annual Reviews, 2025-09) Wingfield, Michael J.; Pham, Nam Q.; Marincowitz, Seonju; Wingfield, Brenda D.; mike.wingfield@fabi.up.ac.za
The chestnut blight pathogen Cryphonectria parasitica is well-known for the devastation it caused to North American forests. It is less well recognized that numerous other fungi in the Cryphonectriaceae are emerging as threats to native and planted forests in the tropics and Southern Hemisphere. Unlike C. parasitica, these fungi, such as Chrysoporthe cubensis, initially gained attention due to a canker disease in plantations of non-native Eucalyptus. More than four decades of research have revealed a wide diversity of Cryphonectriaceae species that infect many other tree genera in the Myrtales. These fungi often exist as endophytes but become problematic when trees are planted outside their native range. Growing numbers of species are also undergoing host shifts from native to susceptible trees such as Eucalyptus, posing serious risks to both natural and planted forests. These fungi provide an example of the biodiversity of tree-infecting fungi that is understudied, despite their significant potential to harm forest ecosystems.
Countability conditions in locally solid convergence spaces
(Springer, 2025-09) Bilokopytov, Eugene; Bohdanskyi, Viktor; Van der Walt, Jan Harm; janharm.vanderwalt@up.ac.za
Please read abstract in the article.
Do climate risks predict US housing returns and volatility? Evidence from a quantiles-based approach
(World Scientific Publishing, 2025-03) Bouri, Elie; Gupta, Rangan; Marfatia, Hardik A.; Nel, Jacobus
This paper analyzes the ability of textual-analysis-based daily proxies of physical (natural disasters and global warming) and transition (US climate policy and international summits) climate risks to predict daily movements in the US housing market in the entire conditional distribution of housing returns and volatility. Using data for the period 2 August 2007 to 29 November 2019, a nonparametric causality-in-quantiles test is used, accounting for nonlinearity and structural breaks between housing returns and climate risk factors. The Granger causality analysis shows that climate risk factors (and the associated uncertainty) predict housing returns and volatility across the entire conditional distribution. These results are robust to alternative daily data of aggregate housing prices for the US and 10 major metropolitan statistical areas. Insights from our findings are beneficial for the decision-making of investors, policymakers and the academic research community.
Warming has limited effects on plant growth through nutrient release : evidence from sub-Antarctic Marion Island
(Oxford University Press, 2025-09) Pallett, Nita C.M.; Ripley, Brad S.; Greve, Michelle; Cramer, Michael D.
Please read abstract in the article.
Ten-year outcomes of antiretroviral therapy : a retrospective cohort study in Tshwane district, South Africa
(BioMed Central, 2025-10) Mhlongo, Kateko; Louw, Murray; Ngcobo, Sanele; sanele.ngcobo@up.ac.za
BACKGROUND : South Africa continues to face one of the world’s highest HIV burdens, with 7.7 million people living with HIV (PLWHIV) in 2023. Despite progress toward UNAIDS 95–95–95 targets, challenges in long-term retention and treatment outcomes persist. This study aimed to evaluate 10-year antiretroviral therapy (ART) outcomes among PLWHIV initiated on treatment in 2013 within Tshwane District, South Africa. METHODS : Retrospective cohort using Tier.Net data from 1,337 adults across 10 randomly selected facilities (clinics and community health centres [CHCs]). Outcomes were retention, loss to follow‑up (LTFU), mortality, viral suppression, and CD4 recovery. We used Kaplan–Meier methods and multivariable models (Cox for LTFU and mortality, logistic for viral suppression, linear for CD4 change). Mortality analyses were limited to participants with complete ascertainment (n = 640). RESULTS : At 10 years, 47.7% were retained, 30.4% LTFU, 20.1% transferred out, and 3.3% died. Attrition was steepest early and most pronounced among 18–24-year-olds. Advanced WHO stage strongly predicted death (Stage III/IV vs. I/II: aHR 3.06, 95% CI 1.26–7.44), and younger age was protective (≤ 34 vs. > 34 years: aHR 0.28, 95% CI 0.09–0.86). Care at CHCs was associated with lower mortality (aHR 0.33, 95% CI 0.13–0.83) and greater CD4 gains (clinic care: −74.35 cells/µL vs. CHCs; p < 0.001). Female sex was associated with larger CD4 recovery (+ 90.06 cells/µL vs. males; p < 0.001). Only baseline CD4 > 200 cells/µL independently predicted viral suppression (aOR for being suppressed ≈ 1.89, derived from aOR 0.53 for non-suppression; p < 0.001). No baseline covariates were significant predictors of time to LTFU (clinic type borderline: HR 0.80, p = 0.086). CONCLUSION : A decade after initiation, fewer than half remained in care. Mortality clustered among older adults and those presenting with advanced disease, while CHC-based care conferred survival and immunologic advantages. Programme priorities should include earlier diagnosis and ART start, youth-friendly retention strategies, and scaling CHC-style differentiated service delivery to improve long-term outcomes.
Advancing legal recognition and community-led reparations for indigenous rights in combating climate change and environmental degradation
(Cambridge University Press, 2025-09) Fehun Aren, Marie-Louise
Designing meaningful reparations for Indigenous communities requires grappling with the enduring effects of historical and contemporary injustices. Despite the existence of international legal frameworks such as the United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP) and International Labour Organization Convention 169, Indigenous peoples around the world continue to experience systemic land dispossession, exclusion from decision making, and environmental harm tied to extractive and infrastructure projects. These harms are often compounded by the lack of formal legal recognition of Indigenous land rights and the failure to uphold principles like Free, Prior, and Informed Consent (FPIC). Addressing these realities demands reparative frameworks that go beyond symbolic recognition, offering structural responses grounded in accountability, restitution, and the restoration of Indigenous autonomy over land and resources.
Diversity and ethnobotanical use-value of trees outside forests on the agricultural landscape of the Mongala Province, Democratic Republic of Congo
(Springer, 2025-09) Azenge, Jean Pierre; Wassila, Ibrahim Seidou; Kassi, Justin N'Dja; Chirwa, Paxie W.
Trees outside forests on agricultural land (TOF-AL) are essential for the livelihoods of rural communities in the Democratic Republic of Congo, yet their diversity, use, and management are poorly documented, particularly in Mongala province. This study aimed to characterize the diversity of TOF-AL species, quantify their ethnobotanical use values, and analyze the management strategies of local communities. We conducted ethnobotanical surveys and tree inventories in 900 agricultural plots across 45 villages in the three territories of Mongala province. The data were analyzed using diversity indices, the total ethnobotanical use value (TUVs) index, and hierarchical clustering analysis to classify species based on their use values. We identified 136 TOF-AL species on agricultural land in Mongala, with a Shannon diversity index of 3.544. The results show that more than 62% of the total abundance is concentrated in ten most common species. The clustering analysis revealed three distinct clusters of 23 privileged species: Cluster 1 (high value for energy and construction), Cluster 2 (high value for commerce and crafts), and Cluster 3 (multifunctional species with high value for food, medicine, and commerce). The high abundance of Cluster 3 species and the rarity of Cluster 2 species indicate that use value directly influences the conservation status of the species. Our results show that the diversity and abundance of TOF-AL are the result of specific management choices guided by local ethnobotanical knowledge. Species that provide continuous and non-destructive benefits are actively conserved by farmers, while those with high commercial value are threatened by intense harvesting pressure. This study calls for the adoption of differentiated management strategies to ensure the sustainability of resources. It suggests targeted reforestation programs and economic incentives for threatened species (Cluster 2) and the strengthening of existing management practices for abundant species (Clusters 1 and 3), underscoring the importance of integrating traditional knowledge into agroforestry conservation.
Breed-specific genetic recombination analysis in South African Bonsmara and Nguni cattle using genomic data
(MDPI, 2025-08) Magagula, Nozipho A.; Mtileni, Bohani; Ncube, Keabetswe T.; Khanyile, Khulekani S.; Zwane, Avhashoni Agnes
South African cattle comprise diverse breeds with distinct evolutionary histories, potentially reflecting differences in recombination landscapes. This study assessed genome-wide recombination rates and hotspots in Bonsmara (n = 190) and Nguni (n = 119) cattle using three-generation half-sib pedigrees genotyped with the Illumina Bovine SNP50 BeadChip. Phasing across 29 autosomes was conducted using SHAPEIT v2, and crossover events were inferred using the DuoHMM algorithm. The total number of crossover events detected was higher in Nguni (n = 8982) than in Bonsmara (n = 7462); however, the average recombination rate per 1 Mb window was significantly higher in Bonsmara (0.31) compared to Nguni (0.18) (p < 0.01). This apparent discrepancy reflects differences in genomic distribution and crossover clustering across breeds, rather than overall recombination frequency. A critical limitation of the study is the reliance on half-sib families with small family sizes, which may underestimate recombination rates due to limited meiotic sampling and increased variance in crossover detection. We identified 407 recombination hotspots in Bonsmara and 179 in Nguni, defined as intervals exceeding 2.5 standard deviations above the mean recombination rate. Genes such as PDE1B and FP which are associated with productions traits were located within hotspot-enriched regions. However, functional causality between these genes and local recombination activity remains unverified. Our results provide statistically supported evidence for breed-specific recombination patterns and hotspot distributions, underscoring the importance of incorporating recombination architecture into genetic improvement strategies for South African cattle.
Investigating bark, ambrosia and nitidulid beetle (Coleoptera : Scolytinae and Nitidulidae) communities and their potential role in the movement of Ceratocystis manginecans in commercial forestry plantations in Riau, Indonesia
(Wiley, 2025-11) Lynn, Kira Mary Theresa; Wingfield, Michael J.; Tarigan, Marthin; Duran, Alvaro; Santos, Samuel A.; Nel, Wilma Janine; Barnes, Irene; irene.barnes@fabi.up.ac.za
Ceratocystis Canker and Wilt Disease (CCWD), caused by the fungal pathogen Ceratocystis manginecans, poses a significant threat to Acacia and Eucalyptus plantations in Indonesia. Infections typically occur through wounds on the main stems of trees, and infected trees, particularly Acacia, are often co-infested by various wood-associated beetles. The aim of this study was to identify the beetle species associated with Ceratocystis-infected trees and to assess their potential role in dispersing C. manginecans. Beetle and frass samples were collected from Ceratocystis-infected compartments of Acacia and Eucalyptus propagated as monocultures in Riau, Indonesia, either by using traps or by direct collection from infected trees. The samples were screened for the presence and viability of Ceratocystis propagules using a quantitative polymerase chain reaction-high-resolution melting analysis (qPCR-HRMA) diagnostic tool and a carrot baiting technique, respectively. Fourteen beetle species, predominantly collected from traps, representing nine genera of the Scolytinae and Nitidulidae, were identified from the two plantation types. The qPCR tool detected the presence of Ceratocystis DNA on 13 of the 14 beetle species at concentrations as low as 0.015–0.0019 ng. However, viable Ceratocystis propagules could not be recovered from these beetles using culture-based methods. Of the 105 frass samples screened, qPCR detected Ceratocystis DNA in 67 samples; however, only one Ceratocystis isolate was obtained using the carrot baiting method. The results of this study suggest that the beetles and beetle frass can harbour Ceratocystis propagules, as indicated by the detection of fungal DNA. However, the viability of the propagules and the ability of the beetles and/or beetle frass to spread C. manginecans requires further investigation.
Ensuring ethical test use in South Africa : the role of Assessment Standards South Africa
(AOSIS, 2025-03) Laher, Sumaya; De Beer, Marie; Maree, David J.F.; Bischof, David A.
Historically, many psychological tests in use in South Africa are imported from Western contexts, creating challenges in applying them across South Africa’s diverse cultural and linguistic groups. The Employment Equity Act No 55 of 1998 prohibits the use of psychological assessments unless they are scientifically validated, reliable and unbiased for use with South Africans. Furthermore, the Health Professions Council of South Africa (HPCSA) plays a key regulatory role in ensuring that only qualified psychology professionals use these tests. The HPCSA’s Professional Practice Committee is currently responsible for classifying tests as psychological or not. The Professional Practice Committee does not evaluate the quality of tests. Recognising gaps in the regulatory framework, the three organisations most involved with psychological assessment in practice (the Psychological Society of South Africa [PsySSA], the Society for Industrial and Organisational Psychology of South Africa [SIOPSA] and the Association of Test Publishers [ATP]) collaborated to form Assessment Standards South Africa (ASSA). As a non-governmental body, ASSA oversees the quality of assessments, ensuring that they meet local and international standards. Assessment Standards South Africa’s guidelines emphasise transparency, ethical standards and the importance of local research to ensure the relevance of tests. Through initiatives such as the Assessment Standards Test Review System, ASSA has streamlined test certification and review processes, promoting responsible and ethical use of psychological and other assessment devices in South Africa. Assessment Standards South Africa offers a best practice model for test reviews to ensure responsible and ethical use of tests in South Africa.
Narratives of risk : parents and community perspectives on food insecurity, alcohol use and sexual risk among adolescent girls in underserved communities
(MDPI, 2025-09) Davids, Eugene Lee; eugene.davids@up.ac.za
Underserved communities in South Africa face persistent inequalities that hinder the health and well-being of young people, particularly during the critical developmental phase of adolescence. This study explored perceptions of adolescent health and well-being among parents/guardians and community leaders of adolescent girls in two underserved communities in Gauteng, focusing on food insecurity, alcohol use, and transactional sex. The sample comprised 63 participants, including parents/guardians of adolescents and community leaders (such as individuals working for community-based organisations or regarded as trusted figures in the community). Two facilitators conducted 11 focus group discussions in English, Sepedi, and isiZulu. All sessions were audio-recorded, translated, and transcribed. The transcripts were analysed using reflexive thematic analysis. The findings reflect community and parental narratives of risk, showing how adolescents in Mamelodi and Soshanguve—two underserved communities in Gauteng—experience food insecurity that contributes to underage drinking and transactional sex, ultimately leading to teenage pregnancies and HIV infection. The results highlight the risks faced by adolescents, showing how social and structural factors create conditions that enable underage drinking and transactional sex, thereby increasing vulnerability to pregnancy and HIV infection. This study highlights the urgent need for interventions that can effectively address these narratives of risk.
Understanding customer grief in brand relationships
(Elsevier, 2026-01) Berndt, Adele; Tierney, Kieran D.
Brands are key in building customer-brand relationships, yet organisations change their product lines by reformulating or discontinuing brands. This results in negative customer emotions, including pain and grief. While identified in marketing, grief has received little academic attention. Thus, this research seeks to explore and develop an understanding of customer grief as pain. The empirical context is the change of a breakfast cereal. By applying netnographic research to eight customer-brand fora, this qualitative study analysed 4,080 online customer posts to understand customer grief. Applying the stages of the Kübler-Ross grief model, this study shows that grief is associated with a misalignment of customers’ expectations, practices, and emotions in response to an unexpected brand change. This generates a more fine-grained understanding of customer grief, providing theoretical and practical implications for organisations in managing their brand relationships. HIGHLIGHTS • The brand is key in building customer-brand relationships, yet organisations change their product lines. • Organisational actions can result in negative customer emotions such as grief. • The empirical context of the study is that of the withdrawal of a breakfast cereal. • This qualitative netnographic study analyses 4,080 online customer posts to understand customer grief. • The study applies the stages of the Kübler-Ross grief model in the context of marketing.

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