Postprints (Articles)

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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.
Tree biomass carbon stocks and biodiversity, and their determinants in a traditional agroforestry landscape in the Vhembe Biosphere Reserve, South Africa
(Springer, 2025-01) Makhubele, Lucky; Chirwa, Paxie W.; Araia, Mulugheta Ghebreslassie
Traditional agroforestry systems have been recognized worldwide for their positive contribution to biodiversity conservation, climate change mitigation, and improving socio-economic livelihood. Little has been reported regarding the effects of ecological determinants (tree density, species richness and diversity) on the biomass carbon accumulation potential of traditional agroforestry in South Africa, especially in the Vhembe Biosphere Reserve (VBR). The main objective of this study was to quantify tree biomass carbon stock and biodiversity in the VBR traditional agroforestry landscape along three distance levels (immediate, intermediate, and far distance) from villages to the forest. Vegetation data was collected using forestry inventory tools. In each distance, nine (9) linear transects (250 m long) were established with five rectangular plots (20 × 10m2) in 10 m apart. The sampling intensity was 10% and the sampling effort achieved was > 80%. Tree diversity metrics and above-and below ground carbon estimates were calculated from the data and then analyzed using PERMANOVA, ANOVA, Spearman’s correlation, and linear regression models. Tree species richness and diversity had no significant effect on carbon stocks, while an effect was found on tree density and elevation. The results showed no statistically significant differences in above-and below ground carbon stocks (F = 0.888, p = 0.413) among distance levels from villages while tree density (F = 19.353, p < 0.05) was found to be increasing with increasing distance from the village to the forest. The results suggest that biomass carbon stocks in traditional agroforestry landscape are independent of species richness and diversity, dependent on tree density. The lower tree density, species richness and diversity at immediate distance implies the effect of proximity disturbance. The immediate distance has a greater potential for high biomass carbon accumulation if the disturbance can be minimized and tree density augmented through planting indigenous tree species and conservation.
Uncertain times require new thinking for agri-food science to ensure food security and nutrition for all
(Elsevier, 2025-11) Fraser, Evan D.G.; Adeyemo, Olanike; Amiot-Carlin, Marie-Josephe; Azam-Ali, Sayed; Caron, Patrick; Cole, Martin; Clapp, Jennifer; Duwayri, Mahmud; Echeverria, Ruben; Elizondo, Cecilia; Elver, Hilal; Lehman, Bernard; Recine, Elisabetta; Schonfeldt, H.C. (Hettie Carina); Serraj, Rachid; Suwa-Eisenmann, Akiko; Tangermann, Stafan; Webb, Patrick; Wright, Iain; hettie.schonfeldt@up.ac.za
For over six decades, international policy has enabled agricultural products to move relatively easily across national borders. Currently, however, the landscape is changing. Deglobalization and the erosion of multilateral principles threaten international food supply chains while climate change is increasingly undermining production. In addition, today's food systems contribute to major environmental and human health problems. The global agri-food research agenda must adapt quickly to these realities. Here we propose that a new research agenda be established based on three principles to help respond to challenging times, promote human rights, sustain gains made in the past, and support greater positive impacts in the future. Principle one – a strengthened commitment to community engagement. Principle two – better supporting interdisciplinary systems thinking. Principles three – combatting misinformation by enabling enhanced public communication. We believe that today's crises present an opportunity to establish the foundations of a food system transformation that is more equitable, transparent, sustainable, and democratic. HIGHLIGHTS The global agri-food research agenda must adapt to multiple environmental, economic and political disruptions.Three principles can frame a new research agenda: • community engagement • interdisciplinary systems thinking • combatting misinformation Today's crises create an opportunity to enhance the impacts of applied science and support human rights.
Maintaining inclusive leadership in a virtual work environment
(AOSIS, 2025-10) Tshabalala, Bridget; Bussin, Mark H.R.
ORIENTATION : The outbreak of the coronavirus disease 2019 (COVID-19) pandemic has pushed companies to reconsider and change how they operate. This article explores how leaders maintain inclusive leadership in a virtual work environment, which promotes employee well-being and inclusivity. RESEARCH PURPOSE : There is minimal literature on how the COVID-19 pandemic has affected workplaces in how they operate. This study aims to explore how leaders maintain inclusive leadership in this new virtual work environment. MOTIVATION FOR THE STUDY : The effectiveness of a leader is enabled by their ability to influence their followers. The virtual work setup necessitates leaders to ensure the contribution of employees, and this can be achieved by an inclusive leader. RESEARCH APPROACH/DESIGN AND METHOD : A qualitative exploratory research method was followed. An inductive thematic analysis was conducted from semi-structured interviews. Fourteen middle- to senior-level managers from various financial institutions, insurance companies and government entities were interviewed. MAIN FINDINGS : There is still a lack of trust by leaders, as they do not give staff freedom to fully make the decisions. Leaders are not adequately trained to adapt to managing virtual teams. PRACTICAL/MANAGERIAL IMPLICATIONS : Leaders are expected to be the driving force of inclusive leadership, thereby contributing positively to employee well-being. Organisations need to fully equip managers by providing continuous training and development. CONTRIBUTION/VALUE-ADD : Inclusion is a capability needed for leaders as they are expected to motivate employees in any organisation. Employees who feel included will positively contribute to the organisation, resulting in the organisation achieving their objectives.
High-order flux splitting schemes for the Euler equations of gas dynamics
(Elsevier, 2025-09) Chu, Shaoshuai; Herty, Michael; Toro, Eleuterio F.
We develop high-order flux splitting schemes for the one- and two-dimensional Euler equations of gas dynamics. The proposed schemes are high-order extensions of the existing first-order flux splitting schemes introduced in Toro and Vázquez-Cendón (2012) where the Euler equations of gas dynamics are split into two subsystems: the advection and pressure systems. In this paper, we formulate the TV splitting within the semi-discrete framework to extend it to higher orders of accuracy for the first time. The second-order extension is obtained by using piecewise linear interpolant to reconstruct the one-sided point values of the unknowns. The third- and fifth-order schemes are developed using the finite-difference alternative weighted essentially non-oscillatory (A-WENO) framework, which is particularly effective in handling multidimensional problems and provides a more straightforward approach to constructing higher-order WENO schemes. These extensions significantly improve the resolution of discontinuities and the accuracy of numerical solutions, as demonstrated by a series of numerical experiments of both the one- and two-dimensional Euler equations of gas dynamics. HIGHLIGHTS • Extended first-order TV splitting to higher orders of accuracy. • Compared the efficiency against CU, HLL, and HLLC schemes. • Demonstrated improved resolution in 1D and 2D Euler equations of gas dynamics.
Design thinking as a pedagogical approach for the Jam, a fast-paced cross-institutional programme with a focus on social justice
(Taylor and Francis, 2025) Nerantzi, Chrissi; Kioupi, Vasiliki; Malone, Cathy; McDonald, Damian; Mushonga, Tafadzwa; Vallance, Simon; Borde, Radhika; Rofe, J. Simon; Parsons, Megan; Roxby Wardle, Naomi; Michel-Villarreal, Rosario; Mack, Annalisa; Bezbaruah, Rishabh; Nyabundi, Agnetta Adiedo; Pullman, Charles
This contribution reports on the design phase of the Jam, a short, fast-paced, cross-institutional online programme over three days. Its focus is on social justice and specifically access, use and management of community space, as integral part of sustainability. This novel programme aims to enable learning, generate ideas to address complex issues, build connections and support diverse community members engage in cultural exchanges. Developed by the University of Leeds in collaboration with the University of Pretoria, ls14trust in Seacroft, and Mothong African heritage in Mamelodi, it brings together educators, professional services staff and students and the public in non-hierarchical ways to inspire new and different ways to interact and learn. We present an account of the design phase of the Jam, including an account of our institutional design context, an overview of literature on Jams and Jamming that informed our design of the Social Justice Jam: Spaces for Change 2024.
Improved class separation by GC x GC of volatile hydrocarbons with an unconventional increase in the second dimension plate number
(Elsevier, 2025-11) Potgieter, H.; Rohwer, Egmont Richard; Joubert, T.
Light petroleum fractions are produced during crude and synthetic oil refining processes and are upgraded to useful products in various markets. These fractions are upgraded using various refining processes, and the characterization of these fractions is essential for process control and ensuring final product specifications. These light fractions can be very complex and multidimensional gas chromatography (GC × GC) is used to characterise these complex samples. ASTM method D1319, Fluorescent Indicator Adsorption (FIA), is used routinely for the determination of the total volume percent of saturates, olefins and aromatics in petroleum fractions and is used in the certification of final gasoline products. There would be several advantages if chemical group-type separation for gasoline can be achieved on GC × GC. Even though excellent GC × GC chemical group-type separation has been achieved, the separation of ≤C6 aliphatics (alkanes, alkenes and cyclic alkanes) in light fuels like gasoline remains a challenge with insufficient resolution between these compounds. In this study, the GC × GC parameters for the optimum separation of the ≤C6 aliphatics were determined with group-type separation of light fuels in mind. The study showed that it is possible to achieve this separation under GC × GC wrap-around conditions whereby two modulations of analytes are moving through the second dimension column at any time, allowing for the use of 2 - 4 times longer second dimension columns. For the first time the optimum separation of the ≤C6 aliphatics were determined while maintaining good separation for the heavier hydrocarbons. Good GC × GC chemical group-type separation for gasoline samples was obtained with this method. Quantitative results, combined with bromine number analysis, compared well with the results obtained by the FIA method. HIGHLIGHTS • GC × GC parameters for the optimum separation of the ≤C6 aliphatics were determined. • Separation under GC × GC wrap-around conditions, allowing longer 2nd dimension columns. • GC × GC chemical group-type separation for gasoline samples obtained with this method. • This method potentially provides an alternative to the FIA method.
Fine-scale associational effects : single plant neighbours can alter susceptibility of focal plants to herbivores
(Public Library of Science, 2025-08) Finnerty, Patrick B.; Banks, Peter B.; Shrader, A.M. (Adrian); McArthur, Clare
The neighbourhood of plants in a patch can shape vulnerability of focal plants to herbivores, known as an associational effect. Associational effects of plant neighbourhoods are widely recognised. But whether a single neighbouring plant can exert an associational effect is unknown. Here, we tested if single neighbours indeed do influence the likelihood that a focal plant is visited and eaten by a mammalian herbivore. We then tested whether any refuge effect is strengthened by having more neighbours in direct proximity to a focal plant. We used native plant species and a browser/mixed feeder mammalian herbivore (swamp wallabies (Wallabia bicolor)) free-ranging in natural vegetation. We found that a single neighbouring plant did elicit associational effects. Specifically, plant pairs consisting of one high-quality seedling next to a single low-quality plant were visited and browsed by wallabies later and less than pairs of two high-quality seedlings. Having more neighbours did not strengthen these associational effects. Compared with no neighbours, one or five low-quality neighbours had the same effect in delaying time taken for wallabies to first visit a plot and browse on a high-quality focal seedling. While traditionally a ‘patch’ refers to a broad sphere-of-influence neighbouring plants have on a focal plant, our findings suggest the influence of plant neighbours can range from the nearest individual neighbour to the entire plant neighbourhood. Such fine-scale associational effects are fundamentally important for understanding intricate plant-herbivore interactions, and ecologically important by potentially having knock-on effects on plant survival, in turn influencing plant community structure.
The BRICS expanded : shaped by - or shaping - the global order?
(Routledge, 2025) De Carvalho, Gustavo; Gruzd, Steven; Wu, Yu-Shan
Policymakers and academics face a persistent puzzle when analysing the BRICS: determining what exactly this grouping wants to achieve. The uncertainty stems from contradictory signals – BRICS countries simultaneously call for reforming global institutions while building their own parallel alternatives; champion multilateralism while actively coordinating positions that challenge Western (especially United States) leadership of multilateralism; and advocate for inclusive governance, while often excluding traditional powers from their arrangements. Is BRICS shaped by, or shaping, the unfolding global order? The contributions to this special issue illuminate different aspects of the ‘shaped vs shaping’ dialectic through three analytical approaches that collectively reveal recurring themes and competing interpretations of BRICS’ transformative potential. The aim is to present new insights for policymakers at the national as well as international level, and to provide valuable research to scholars and students of international affairs.
Fiscal autonomy and the path to sustainable local economic development : a multilevel municipal analysis in South Africa
(Wiley, 2025-10) Monkam, Nara F.; Saba, Charles Shaaba
Despite fiscal reforms aimed at achieving Sustainable Development Goal Target 17.1—strengthening domestic resource mobilization for development—the impact of fiscal autonomy on local economic development (LED) in South Africa remains underexplored. Therefore, this study examines the impact of fiscal autonomy across 248 municipalities from 2009 to 2023, employing a range of advanced econometric methods. The results highlight a complex relationship: System Generalized Method of Moments analysis shows fiscal autonomy negatively affects LED in metropolitan municipalities (Category A) but has positive effects in the full sample, as well as in district (Category C) and local municipalities (Category B). The methods of moments quantile bootstrap regression shows that fiscal autonomy promotes LED across all quantiles for the full sample and in Category B. However, Category A exhibits a negative impact, whereas Category B shows an insignificant negative effect across all quantiles. These findings emphasize the need for differentiated policies. Metropolitan municipalities require targeted governance and fiscal reforms to mitigate negative outcomes while expanding fiscal autonomy for local and district municipalities could significantly enhance LED. This research offers practical insights for tailored fiscal strategies, promoting sustainable economic growth across South Africa's varied municipal landscapes.
Process capability indices for Marshall–Olkin inverse log-logistic distribution
(Springer, 2025) Aako, Olubisi Lawrence; Adekeye, Kayode Samuel; Adewara, Johnson Ademola; Malela-Majika, Jean-Claude; malela.mjc@up.ac.za
Process capability analysis is a vital tool in quality management that enables organizations to evaluate and enhance their processes. Real-world data are mostly non-normal, they often deviate from the assumption of normality. The estimators of process capability indices (PCIs) for normal processes are not sufficient to characterize non-normal processes and can give misleading results. The Marshall-Olkin inverse log-logistic (MO-ILL) distribution is a flexible distribution that can effectively model data exhibiting positive skewness, asymmetry and heavy tails. In this paper, we derived the process capability indices (PCIs) based on the MO-ILL distribution when the process is assumed to be in a state of statistical control. Two PCIs based on MO-ILL mean and variance, and MO-ILL quantiles are proposed. The proposed PCIs were compared with the traditional PCIs and percentile-based PCIs using two real life data and data generated from MO-ILL distribution. Moreover, the effect of the sample size and parameters of the MO-ILL distribution on the PCI measures is also investigated. The results showed that PCIs values based on the proposed MO-ILL mean and variance, and MO-ILL quantiles are respectively lower and better than the traditional PCIs and percentile-based PCIs. This is an indication that MO-ILL distribution-based methods developed have narrow margin of error and are more appropriate in assessing the performance of a skewed process.
Numerical investigation of heat transfer performance of hybrid nanofluid in porous substrate in microchannel heat sink
(Springer, 2025-07) Oladetan, Jeremiah O.; Fujah, Faridat M.; Omosehin, Oluwasegun S.; Atofarati, Emmanuel O.; Nwabuko, Uzo; Olakoyejo, Olabode T.; Adelaja, Adekunle O.; omosehin.os@up.ac.za
With the increasing integration of integrated circuits (ICs) in electronic devices such as electric vehicles, computer data centers, heat pipe technology, solar energy, and heating ventilation, air conditioning, and refrigeration (HVACR) systems, optimizing heat transfer becomes essential to ensure optimal performance and longevity. This study numerically investigates the thermal and hydraulic performance of a microchannel heat sink (MCHS) enhanced by hybrid nanofluids and porous substrate integration. A two-phase Eulerian–Eulerian model implemented in ANSYS Fluent is employed to simulate Al₂O₃/Cu–water hybrid nanofluid flow at volume concentrations ranging from 0.1 to 3.0%, and flow Reynolds number (200 < Re < 1000) with a porous substrate embedded midway along the flow path. The results reveal that both the nanoparticle concentration and Reynolds number significantly enhance heat transfer, reflected in higher average Nusselt numbers and reduced thermal resistance. The incorporation of a porous substrate further amplifies heat transfer, achieving a maximum enhancement of 80.29% compared to the baseline configuration. Overall, employing hybrid nanofluids and porous substrates improves MCHS performance, offering augmented heat transfer efficiency and thermal performance.
Approaches to modelling spatial data using skewed distributions with an application to disease mapping
(Taylor and Francis, 2025) Ayalew, Kassahun Abere; Manda, S.O.M. (Samuel); Cai, Bo
In disease mapping, estimating spatial patterns is typically done by fitting Gaussian spatial models. However, this assumption may not always be correct, as there is a possibility that the spatial random component could follow a skewed and non-symmetric distribution. We propose two spatial statistics methods based on the skew-normal and skew-Laplace spatial distributions to model the spatial random effects. These approaches leverage the unique properties of skewed distributions to capture the inherent asymmetry in spatial data, providing a more accurate representation of complex disease risk. We compared the performance of our proposed non-normal spatial models with existing methodologies through simulation studies. To demonstrate the applicability of our approach, we analysed adult HIV and infant mortality in South Africa. This demonstration highlights our models' effectiveness and provides valuable insights into their practical relevance in public health research.
Derivation of a multivariate longitudinal causal effects model
(Taylor and Francis, 2025) Twabi, Halima S.; Manda, S.O.M. (Samuel); Small, Dylan S.; Kohler, Hans-Peter
This paper presents a causal inference estimation method for longitudinal observational studies with multiple outcomes. The method uses marginal structural models with inverse probability treatment weights (MSM-IPTWs). In developing the proposed method, we re-define the weights as a product of inverse weights at each time point, accounting for time-varying confounders and treatment exposures and possible correlation between and within (serial) the multiple outcomes. The proposed method is evaluated by simulation studies and with an application to estimate the effect of HIV positivity awareness on condom use and multiple sexual partners using the Malawi Longitudinal Study of Families and Health (MLSFH) data. The simulation study shows that the joint MSM-IPTW performs well with coverage within the expected 95% level for a large sample size (n = 1000) and moderate to strong between and within outcome correlation strength (𝜌𝑗=0.3, 0.75, 𝜌𝑘=0.4, 0.8) when the effects are similar. The joint MSM-IPTW performed relatively the same as the adjusted standard joint model when the treatment effect estimate was the same for the outcomes. In the application, HIV positivity awareness increased the usage of condoms and did not affect the number of sexual partners. We recommend using the proposed MSM-IPTWs to correctly control for time-varying treatment and confounders when estimating causal effects for longitudinal observational studies with multiple outcomes.
Understanding barriers to pre-exposure prophylaxis (PrEP) uptake among young people in Lower Gweru, Zimbabwe. A qualitative study
(Routledge, 2025) Jimu, Christopher; Nyamaruze, Patrick; Moyo, Freely Tanatswa; Makaye, Jeriphanos
Pre-exposure prophylaxis (PrEP) is a highly effective strategy for preventing HIV infection when taken as prescribed. Most studies have focused on adult populations and other vulnerable groups, such as men who have sex with men (MSM) while few studies have explored the barriers young people face toward PrEP uptake yet they contribute a worrying percentage of new infections and HIV related deaths. We conducted 17 in-depth interviews with young people aged 15–24 years and key informants in Lower Gweru, Zimbabwe. Findings highlighted that young people face numerous barriers such as fear of side effects, pill burden, and lack of PrEP awareness. We concluded that addressing challenges to PrEP uptake requires a multifaceted approach that includes improving accessibility and education, as well as addressing cultural and social barriers. Implementing these recommendations can significantly enhance PrEP uptake, ultimately contributing to national HIV prevention goals and better health outcomes for young populations
Diuresis during 18F-flotufolastat (rhPSMA-7.3) PET/CT improves recurrence detection after prostatectomy : a prospective Phase II trial
(Society of Nuclear Medicine and Molecular Imaging, 2025-02) Lawal, Ismaheel Opeyemi; Mushtaq, Aliza; Jani, Ashesh B.; Rupji, Manali; Dhere, Vishal R.; Patel, Sagar A.; Bilen, Mehmet A.; Patel, Pretesh R.; Sebastian, Nikhil T.; Switchenko, Jeffrey M.; Schuster, David M.; Marcus, Charles
Please read abstract in the article.
Cancer and fertility management : FIGO best practice advice
(Wiley, 2025-10) Purandare, Nikhil; Ruiloba, Francisco; Nguyen-Hoang, Long; Wilailak, Sarikapan; Yanaihara, Nozomu; Chung, Jacqueline P.W.; Malhotra, Jaideep; Mocanu, Edgar; Amant, Frederic; McNally, Orla; Peters, Inge; Flynn, Katie; El Helali, Aya; Maxwell, Cynthia; Adam, Sumaiya; Bergman, Lina; Nanda, Surabhi; Guinto, Valerie Tiempo; McAuliffe, Fionnuala M.; Nelson-Piercy, Catherine; Nana, Melanie; Smith, Graeme; Berek, Jonathan; O'Reilly, Sharleen; O'Brien, Pat; Jacobsson, Bo; Poon, Liona C.
Cancer diagnoses in patients of reproductive age require balancing urgent oncological treatment with the need to preserve fertility. This FIGO Best Practice Advice outlines key considerations for fertility management in this population given the rising cancer incidence among young women and the reproductive risks posed by cancer treatments. The guidance evaluates the impact of chemotherapy, radiotherapy, surgery, and emerging therapies—such as targeted agents and immunotherapies—on gonadal function and fertility. Established fertility preservation methods, including oocyte/embryo cryopreservation, sperm banking, and ovarian tissue freezing, are detailed alongside barriers to their adoption, such as cost and limited access. Early collaborative counseling with oncologists and fertility specialists is central to addressing timelines, psychological impacts, and priorities. Post-treatment pathways, including assisted reproduction and surrogacy, are also explored. The guidance stresses the importance of integrating fertility-sparing interventions and fertility preservation into cancer care while advocating for equitable access to resources. Further research is needed to refine preventive interventions, evaluate long-term outcomes, and expand options for survivors globally. By prioritizing fertility preservation within oncological care, healthcare providers can better support the holistic needs of young individuals facing cancer.
‘Silent losses–silent data’ : reviewing stillbirth data quality in low- and middle-income countries using data quality dimensions
(Wiley, 2025) Pandey, Anuj Kumar; Neogi, Sutapa Bandyopadhyay; Gautam, Diksha; Thomas, M. Benson; Basu, Jayati; Basu, Debashis; Widyastari, Dyah Anantalia
Precise data is crucial for policy decision-making, especially in sensitive outcomes like stillbirth, where each data element have significant effects. Following years of advancement in the healthcare domain, there is a pressing need to improve data-based policymaking by addressing both the social context and emotional dimensions. This holds true for any healthcare condition including stillbirth, which demands the attention of healthcare managers, researchers and policymakers. Conditions such as stillbirth signify more than a birth devoid of vital signs. A mother endures months of discomfort and excruciating labour pain and faces the devastating reality that her baby is no longer alive. The absence of her child's initial cry disrupts her life, causing her to struggle with confusion and sadness on the factors that may have led to this catastrophe. In spite of this significant loss, we typically perceive it as merely one death, often neglecting to acknowledge it adequately. Significant advancements in averting stillbirths can be achieved by viewing it as a loss of life, rather than only perceiving it as the birth of a lifeless infant. Examining stillbirth data and comprehending its causes can aid in formulating strategies to avert future incidents. This publication seeks to compile information on the principal issues associated with the reporting and recording of stillbirths in low- and middle-income countries (LMICs) from the perspective of data quality aspects. Furthermore, it also proposes strategies to enhance each aspect of data quality like harmonising stillbirth definitions, linking routine data systems with surveys, facility audits for better data capture, and increasing funding for stillbirth-related research etc. HIGHLIGHTS • Progress in stillbirth prevention needs robust data for informed decision making. • Concerns in LMIC stillbirth data: no targets, misclassification, fear, stigma etc. • Study recommends better data capture via audits, system links and funding.
Infection rates of Fasciola spp. in cattle slaughtered at 13 abattoirs in six of nine provinces of South Africa
(Elsevier, 2025-06) Nukeri, Sophy; Malatji, Mokgadi Pulane; Sithole, Msawenkosi I.; Ngcamphalala, Philile I.; Nyagura, Ignore; Tembe, Danisile; Ndlovu, Innocent Siyanda; Chaisi, Mamohale E.; Mukaratirwa, Samson
Fasciolosis or liver fluke infection is a snail-borne disease that affects the productivity of domestic ruminants including liver condemnation especially in cattle. However, there is paucity of information on the burden of infection due to lack of accurate data on liver condemnation related to correct geographical origin of infected animals. This distorts perception of the geographical occurrence of fasciolosis, particularly in South Africa among other countries. We aimed to determine the infection rates of Fasciola spp. in cattle slaughtered at selected abattoirs in South Africa. A total of 13 abattoirs consisting of 10 high throughput and three low throughput abattoirs across six provinces, were visited to screen for liver fluke infection in slaughtered cattle including tracing of the animals' geographical origin. A total of 57 livers from 673 slaughtered cattle (8.5 %) from 10 abattoirs were infected with Fasciola spp.. The highest infection rate from the study sites was 37 % and the lowest 4.5 %. Tracing of infected cattle showed that some abattoirs slaughtered cattle originating from other provinces. Forty-nine percent (29/57) of infected cattle had moderate body condition score (BCS) and recorded the highest intensity of fluke infection (>100 flukes per liver). Furthermore, young animals had high infection rates (51 %; 29/57) compared to adults (49 %; 28/57) and females (54 %; 31/57) compared to males (46 %; 26/57). The overall results highlighted the presence of Fasciola spp. in five provinces of South Africa, represented by more than four agro-ecological zones. Fasciola hepatica occurred in all six provinces while both Fasciola spp. co-occurred in one province. Furthermore, F. hepatica constituted the highest percentage (74 %; 710/960) of Fasciola spp. specimens collected. Fasciola gigantica were collected from abattoirs in one province and constituted 26 % (250/960) of the total collected flukes. Results from the study provide information on the burden of fasciolosis in cattle. This is based on abattoir surveys in South Africa, considering the traced geographical origin of animals slaughtered. Using data from surveys of this nature might support efforts to map the geographical distribution of fasciolosis in South Africa. Thus, contribute towards the development of effective control and treatment programs of fasciolosis to mitigate the burden of the disease in cattle. HIGHLIGHTS • Fasciolosis is prevalent in cattle slaughtered at abattoirs from six provinces of South Africa. • Cattle movement for slaughter distorts the true prevalence at provincial level. • Cattle movement may contribute to introduction of infections to new areas. • Fasciola hepatica was recorded in all six provinces. • Fasciola gigantica co-occurred with F. hepatica in the Limpopo province.
Turing patterns across geometries : a proven DSC-ETDRK4 solver from plane to sphere
(Elsevier, 2025-08) Owolabi, Kolade M.; Pindza, Edson; Mare, Eben
This paper presents a unified and robust numerical framework that combines the Discrete Singular Convolution (DSC) method for spatial discretization with the Exponential Time Differencing Runge–Kutta (ETDRK4) scheme for temporal integration to solve reaction–diffusion systems. Specifically, we investigate the formation of Turing patterns – such as spots, stripes, and mixed structures – in classical models including the Gray–Scott, Brusselator, and Barrio–Varea–Aragón–Maini (BVAM) systems. The DSC method, employing the regularized Shannon’s delta kernel, delivers spectral-like accuracy in computing spatial derivatives on both regular and curved geometries. Coupled with the fourth-order ETDRK method, this approach enables efficient and stable time integration over long simulations. Importantly, we rigorously establish the necessary theoretical results – including convergence, stability, and consistency theorems, along with their proofs – for the combined DSC-ETDRK4 method when applied to both planar and curved surfaces. We demonstrate the capability of the proposed method to accurately reproduce and analyze complex spatiotemporal patterns on a variety of surfaces, including the plane, sphere, torus, and bumpy geometries. Numerical experiments confirm the method’s versatility, high accuracy, and computational efficiency, making it a powerful tool for the study of pattern formation in reaction–diffusion systems on diverse geometries.

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