Research Articles (University of Pretoria)

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

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Spectral adventures in quantum realms : nonlinear schrödinger dynamics, quantum vortices and time-resolved wave mechanics
Owolabi, Kolade M.; Pindza, Edson; Mare, Eben (World Scientific Publishing, 2026)
In this paper, we present a comprehensive study of quantum wave phenomena using Fourier spectral numerical methods. The focus is on three interrelated topics: (1) the nonlinear Schrödinger equation (NLS) in physical systems, including optical solitons and Bose–Einstein condensates (via the Gross–Pitaevskii equation, GPE); (2) simulations of the time-dependent Schrödinger equation (TDSE) to explore quantum tunneling, wavepacket dynamics and interference; and (3) the characteristics of quantum turbulence and vortices in superfluid systems. We develop the mathematical formulations of NLS and GPE, highlighting how spectral methods efficiently capture their solutions’ high-frequency content and conserved quantities. We detail the implementation of Fourier pseudo-spectral discretization combined with split-step (operator splitting) time integration, evaluating its accuracy and stability. We also discuss numerical error analysis and comparisons with alternative discretization approaches (finite differences and finite elements). The results include simulations of soliton propagation over long distances without shape distortion, quantum tunneling of wavepackets through potential barriers, and formation of vortex lattices and turbulent energy cascades in condensates. Visualizations such as soliton amplitude profiles, probability density snapshots of tunneling wave functions, and vortex lattice images are provided to illustrate these phenomena. Our findings underscore the spectral method’s superior accuracy (exponential convergence for smooth solutions) and its ability to preserve physical invariants over long simulation times. We conclude that Fourier spectral techniques offer a robust and precise framework for graduate-level research and emerging applications in nonlinear and quantum wave systems.
Ring the alarm: Project 2025's anti-DEI threat to higher education
Holmes Iv, Oscar; Nkomo, Stella M., 1947-; Ruggs, Enrica N. (Emerald, 2026)
PURPOSE : The purpose of this essay is to shed light on the implications of Project 2025 for diversity, equity and inclusion (DEI) in management education and practice. DESIGN/METHODOLOGY/APPROACH : We review the Project 2025, corresponding executive orders, and state laws that relate to reduce or eliminating DEI programs and goals. FINDINGS : We highlight the ways in which anti-DEI actions are harming and may continue to harm DEI scholars and practitioners. We then offer recommendations on ways to resist anti-DEI attacks. ORIGINALITY/VALUE : This essay highlights the role of scholars in the larger battle to uphold DEI values.
Creativity levels of engineering graphics and design students in conventional and digital modelling
Ndlela, Lucky; Rauscher, Willem Johannes; Candiotes, Vernon John (Springer, 2026-01)
Creativity is an important skill for the 21st century, prompting schools to emphasise it as an essential educational goal. The literature suggests that a problem-based learning environment supported by digital technology has the potential to foster students’ creativity. However, little is known about the influence of digital technology on students’ creativity in the context of engineering design within the field of Technology Education. Therefore, this study aimed to investigate the creativity levels of Engineering Graphics and Design (EGD) students in both conventional and digital modelling during problem solving. Using the postpositivist paradigm and a one-group pre-test post-test design, this study reports the creativity levels of 32 s-year Bachelor of Education degree students majoring in EGD. The students were tasked with designing a house individually, first using conventional modelling tools, and then using a digital modelling tool. The creativity in producing their products was measured using the Creative Product Semantic Scale (CPSS). The findings indicated that the students achieved a higher mean creativity score in the post-test than in the pre-test. A paired-sample t-test revealed a statistically significant difference between the mean creativity scores of conventional modelling and digital modelling. This finding indicates a robust association between digital modelling and enhanced student creativity, accompanied by a large effect size. This study has the potential to provide insights into classroom pedagogy for fostering students’ creativity. Future research should explore how different digital modelling tools and design problems influence students’ creativity. Additionally, research should focus on how students collaboratively solve design problems using digital tools.
Strategies and outcomes in school meal programmes : analysing the impact of domestic and international sourcing on feeding modalities
Huni, Chamunorwa; Sari, Ni Putu Wulan Purnama; Duong, Minh-Phuong Thi; Mazenda, Adrino; Budiono, Davy; Nguyen, Minh-Hoang; Vuong, Quan-Hoang (Emerald, 2026)
PURPOSE : The feeding modalities used in school meal programmes – such as breakfast, lunch, dinner, snacks and take-home rations – are influenced by various factors, including supply chain constraints and technical challenges in food distribution. The methods of supply sourcing, whether through domestic or foreign food reserves via in-kind donations or purchases, play a critical role in shaping the feeding options provided. Therefore, this study aims to examine the relationship between various supply-sourcing strategies, i.e. domestic and foreign in-kind donations and purchases and the feeding modalities applied in school meal programmes. DESIGN/METHODOLOGY/APPROACH : The Bayesian Mindsponge Framework, combining the reasoning strengths of Mindsponge Theory and inference advantages of Bayesian analysis, was employed on a dataset of government representatives who manage large-scale school meal programmes across 126 countries. FINDINGS : The findings revealed that sourcing supplies through in-kind donations from neighbouring or distant countries showed a highly reliable negative relationship with the feeding modalities of school meal programmes, while those from the national bodies showed an ambiguous relationship. The purchasing methods – whether domestic or foreign – tended to exhibit positive relationships with feeding modalities, though these relationships were only weakly reliable. ORIGINALITY/VALUE : The findings reveal substantial room for improvement in the effectiveness of supply purchasing strategies in enhancing school meal programmes’ feeding modalities. Further research is needed to examine the impact of sourcing supplies through domestic in-kind donations on feeding outcomes. Additionally, developing strategic plans to optimize the use of in-kind donations from international organizations is strongly recommended to avoid their negative consequences and further enhance programme effectiveness.
Optimal consumption of traditional green leafy vegetables among young children aged 2–6 years in South Africa : a scoping review
Semenekane, Nkululeko Milton; Pretorius, Beulah; Schonfeldt, H.C. (Hettie Carina) (Springer, 2026-01-10)
BACKGROUND : One major global public health concern is the incidence of micronutrient deficiencies in young children, which significantly impacts populations in Low and Middle-Income Countries (LMICs). Traditional Green Leafy Vegetables (TGLVs) are an essential component of regular diets in many cultures around the world. It has been part of the food system for decades and its consumption has been associated with numerous health benefits and bioactive compounds. OBJECTIVE : To map the available evidence on the consumption, nutritional benefits, cultural significance, or potential challenges towards the consumption of traditional green leafy vegetables in the diets of young children aged 2–6 years. METHODS : A comprehensive search strategy was used to identify relevant literature tailored to PubMed/MEDLINE, Scopus, Web of Science, CAB Abstracts and other sources. The selection criteria were based on the Arksey and O’Malley framework and guided by PRISMA with extension for Scoping Reviews (PRISMA-ScR). The search was mainly focused in South Africa (296 articles). After removing 139 duplicates, a total of 157 research articles were screened. In the data extraction phase, 36 articles were selected. RESULTS : The review revealed that TGLV consumption among young children in South Africa varies considerably by region, socioeconomic status with urban versus rural settings. Sample sizes ranged from 30 to 1530 participants which includes young children, caregivers and household heads. CONCLUSION : The review findings provide a foundation for developing contextually appropriate, evidence-informed recommendations to optimise TGLV consumption among young South African children, which may provide a long-term solution to ongoing nutritional challenges while preserving cultural food identities.
Emerging strategies for targeting vasculogenic mimicry in breast cancer treatment
Sekoba, Nare; Demetriou, Demetra Danielle; Chauke-Malinga, Nkhensani; Mabeta, Peaceful Lucy (Springer, 2026-01-20)
Breast cancer represents the most commonly diagnosed malignancy worldwide and is the fourth leading cause of cancer-related mortality. Approximately 2.3 million new cases of breast cancer were diagnosed worldwide in 2022, accounting for 11.6% of all cancer cases, with approximately 670,000 associated deaths. Breast tumors frequently present with abnormal and highly vascularized networks, promoting accelerated growth and contributing to metastatic potential. Increased vascularization often indicates a more aggressive cancer and significantly affects breast cancer treatment. While angiogenesis offers potential therapeutic targets, it also complicates treatment strategies. Anti-angiogenic drugs such as bevacizumab, which target vascular endothelial growth factor-A signaling, have shown potential in limiting tumor growth. However, their success has been limited, as tumors can develop resistance through alternative pathways. Aggressive breast cancer cells, regardless of estrogen-receptor status, can form vessel-like structures through vasculogenic mimicry. This phenomenon also enables them to evade anti-angiogenic treatment and contributes significantly to tumor resistance to various therapeutic interventions. Moreover, vasculogenic mimicry-positive breast cancer patients exhibit high tumor grade, increased invasiveness, metastasis, and poorer survival outcomes as compared to vasculogenic mimicry-negative breast cancer patients. At present, there are no clinically approved therapies that specifically target vasculogenic mimicry in breast cancer. The intricate molecular mechanisms involved in vasculogenic mimicry within breast cancer present considerable challenges to the development of effective therapeutic strategies. Achieving therapeutic breakthroughs that address this phenomenon would represent a major step in the management of breast cancer. This review examines key molecular pathways that regulate vasculogenic mimicry in breast cancer and assesses the potential of targeting vasculogenic mimicry for therapeutic intervention.
Reasoning and proof in mathematics education : a systematic literature review
Lessing, Mary-Jane; Ogbonnaya, Ugorji Iheanachor (Springer, 2026)
This study presents a systematic literature review of 80 publications on reasoning and proof in mathematics education from 2019 to 2024. This review examined the distribution of the studies across mathematics content areas, educational levels, year of publication, and countries. In addition, it examined the instructional strategies and interventions that promote students’ reasoning and proof, the common challenges students encounter in understanding and engaging with reasoning and proof in mathematics, and teachers’ knowledge, beliefs, and attitudes towards reasoning and proof. The results show that most studies focused on geometry, with an apparent increase in research activity between 2019 and 2023. There were studies from 29 nations, thus signifying that reasoning and proof in mathematics education are internationally important. Türkiye, the United States, and Indonesia were the top three countries where the studies were carried out. Most of the studies were at the pre-service teacher education level, followed by the secondary school education level. The Guide-redirecting Warrant Construction instructional approach was found to be effective in improving students’ reasoning and proof. Furthermore, students have difficulty with reasoning and proof, which is aggravated by teachers’ low proficiency in these areas. The study identified important gaps in the literature and offered recommendations to address them.
Coaxial electrospinning as a promising technique for fabricating advanced materials for energy storage applications
Alli, Yakubu Adekunle; Bamisaye, Abayomi; Ige, Akinsanmi S.; Elabor, Rabi; Ife-Adediran, Oluwatobi; Samson, Adanlawo Olayinka; Oni, Samuel Oluwadadepo; Yeboah, Alfred; Bankole, Owolabi Mutolib; Fapojuwo, Dele Peter; Ogunlaja, Adeniyi Sunday (Springer, 2026-01-12)
As the demand for efficient, high-performance energy storage systems intensifies, the need for innovative materials that can enhance energy density, power output, and cycle stability has become paramount. Coaxial electrospinning, a versatile nanofabrication technique, has emerged as a powerful method for producing advanced core-shell nanofibers with tailored properties specifically designed for energy storage applications. This review delves into the principles of coaxial electrospinning, highlighting its advantages over conventional fabrication techniques in creating multifunctional materials for batteries and supercapacitors. By manipulating the core and shell compositions, coaxial nanofibers offer superior ion/electron transport, mechanical stability, and electrochemical performance. The review discusses the latest breakthroughs in the field, including material selection, fiber design strategies, and the resulting improvements in energy storage capacity and durability. Challenges and future opportunities for scaling coaxial electrospinning to meet commercial demands are also explored, positioning this technique as a promising frontier for next-generation energy storage solutions.
Taxonomy, distribution and dispersal of Calonectria species : important pathogens of forestry, agricultural and horticultural crops
Liu, QianLi; Wingfield, Michael J.; Duong, Tuan A.; Wingfield, Brenda D.; Crous, Pedro W.; Chen, ShuaiFei (Springer, 2026-01-19)
PURPOSE OF THE REVIEW : Calonectria is a globally distributed genus of plant-pathogenic fungi causing destructive diseases across a wide range of woody and herbaceous hosts. This review synthesizes recent advances in the species delimitation, host range dynamics, reproductive strategies, and global dispersal patterns of Calonectria. Particular attention is given to the ecological adaptability, cryptic diversity, and climate-driven shifts in distribution of these important fungi. The review identifies key knowledge gaps and provides recent research regarding genome-based diagnostics, adaptive disease management, and forward-looking biosecurity measures. RECENT FINDINGS : Polyphasic taxonomic approaches and molecular systematics have substantially refined the classification of Calonectria, which now includes 136 species grouped into 11 species complexes. Some species, such as Ca. pseudonaviculata, exhibit strict host specificity; others like Ca. pauciramosa have wide host ranges and are globally invasive. Both sexual and asexual reproduction enhance persistence and facilitate dispersal, often via infected nursery stock and contaminated substrates. Climate change is projected to expand the distribution of multiple Calonectria species into new regions. Despite increasing reports of international spread, genomic surveillance remains limited, and diagnostic inconsistencies continue to hinder effective detection and containment. SUMMARY : The broad host range, complex reproductive biology, and environmental adaptability of Calonectria species enhances their growing threat to plant health worldwide. Their spread is accelerated by global trade and climate change, while unresolved taxonomic challenges and underdeveloped molecular tools constrain opportunities for their management. Integrated strategies that combine phylogenomics, risk modeling, and coordinated surveillance are urgently needed to mitigate its impact across agricultural, horticultural, and forest systems.
Increasing targeted poaching of lions for trade has the potential to pose an existential threat to the species in Africa
Lindsey, Peter Andrew; Nicholson, Samantha K.; Coals, Peter G.R.; Taylor, William Andrew; Becker, Matthew Smith; Rademeyer, Kerri; Briers-Louw, Willem Daniel; Almeida, João S.; Chase, Michael J.; Dore, Ashleigh; Henschel, Philipp H.; Kwiyega, Jonathan Lucas; Loveridge, Andrew J.; Mandisodza-Chikerema, Roseline L.; Mandinyenya, Bob R.; Nampindo, Simon; Roodbol, Marnu; Whittington-Jones, Gareth M.; Uiseb, Kenneth Heinrich; Naude, Vincent N.; Williams, Vivienne Linda (Wiley, 2026-01)
Lions (Panthera leo) in Africa are targeted for the illegal wildlife trade, driven by demand in African and Asian markets, for their body parts. This threat is distinct from traditional drivers of lion decline such as prey depletion, habitat loss, and persecution and is poorly understood, underreported, growing, and prone to the influence of organized transnational crime. Here, we synthesize the current state of knowledge on targeted poaching for lion parts, identify key conservation and legal challenges, and propose a coordinated response agenda, drawing on examples from around the continent. We call for consideration in six critical areas: improving in situ protection, effective engagement of communities in conservation interventions, improved understanding of trade dynamics, disrupting the trade via multiple mechanisms, strengthening legal frameworks, and demand reduction. We recommend a proactive approach to prevent entrenchment of poaching and illicit markets and avert severe impacts on lion populations. Without coordinated action to address targeted poaching, there is a significant risk of lion population declines and extirpations. Urgent action is needed to acknowledge and address this issue, because it represents a potentially existential threat to the species.
The strong path partition conjecture holds for α=9
De Wet, Johan P.; Frick, Marietjie (University of Zielona Góra, 2026)
Please read abstract in the article.
Cross-continental soil prokaryotic traits driven by precipitation regime and land cover
Donhauser, Jonathan; Han, Xingguo; Doménech-Pascual, Anna; Jordaan, Karen; Casas-Ruiz, Joan P.; Ramond, Jean-Baptiste; Romaní, Anna Maria; Frossard, Aline; Priemé, Anders (Nature Research, 2026-01)
Trade-offs among traits determine microbial community dynamics and affect soil carbon-cycling feedback to climate change. Here, we determined soil prokaryotic traits based on a novel marker gene-based workflow using cross-continental temperature and aridity gradients. Genome streamlining and high 16S rRNA gene copy numbers per genome (RRN) conferred high maximal growth rates, possibly by allowing for smaller cells with higher surface to volume ratio. Small genomes and high maximal growth rates were found under high precipitation seasonality and in barren soils. Large genomes and low maximal growth rates were found in forests, characterized by high water availability and by abundant and complex organic resources. Our findings suggest that large genomes confer versatility to cope with resource fluctuations and moderate climatic fluctuations while extreme climatic fluctuations and scarcity of resources promote genome streamlining. Seasonal fluctuations in water availability were associated with the ability to form spores and with rapid resuscitation, promoted by high RRN. Moreover, Prokaryotes were less dispersal limited compared to Fungi, presumably due to their smaller size, but within Prokaryotes, small taxa were not more ubiquitous. Our trait-based framework highlights that particularly changes in precipitation patterns and vegetation type will cause changes in microbial processes under future climate.
Breeding male mole-rats (Fukomys) use strong bites to defend reproductive monopoly
Sumbera, Radim; Kraus, Andrea; Mikula, Ondrej; Okrouhlik, Jan; Measey, John; Begall, Sabine; Bennett, Nigel Charles; Zottl, Markus; Herrel, Anthony; Lovy, Matej (Nature Research, 2026-01)
Bite force is a simple trait indicating an animal’s performance related to foraging, social dominance, and defence, all of which influence individual reproductive success. We examine the effect of breeding status on bite force in four social species of Fukomys, a genus of subterranean African rodents (Bathyergidae). These species are cooperative breeders, where reproduction is limited typically to a breeding pair. We collected in vivo bite force data, head width, and upper incisors width from 404 individuals from 75 families and tested whether breeders exhibit stronger bite force. We reveal that breeding males of all four species outperform non-breeders, with bite force in non-breeding males and females being 12% and 22% lower, respectively. In contrast, breeding females underperform relative to other categories, with bite force approximately 31% lower than in breeding males, and many are reluctant to bite. Head width and upper incisors width corroborate these findings. We propose that breeding males require a stronger bite force because of repeated competition with non-related males that may try to enter the family. In contrast, there is much less competition for the breeding position among females, as females rarely intrude into established families.
Relative validity of surrogate measures within the global leadership initiative on malnutrition (GLIM) phenotypic criteria for diagnosing adult malnutrition in resource-constrained settings
Van Tonder, Esmarie; Wenhold, Friedeburg Anna Maria; Esterhuizen, Tonya M.; Blaauw, Reneé (Wiley, 2026-02)
BACKGROUND AND AIM : Implementing the Global Leadership Initiative on Malnutrition (GLIM) diagnostic criteria may improve adult malnutrition identification. Some GLIM parameters are challenging to obtain in resource-constrained settings. We assessed the relative validity of accessible surrogates in substituting accepted phenotypic diagnostic criteria within GLIM. METHODS : In a prospective diagnostic accuracy study, adult ambulatory patients with diverging diagnoses from five South African hospitals were consecutively sampled. The Malnutrition Universal Screening Tool (MUST score≥1) and GLIM diagnostic criteria determined malnutrition risk and diagnosis respectively. Surrogates investigated for appendicular skeletal muscle mass index (ASMMI), measured by multifrequency bio-electrical impedance, were mid-upper arm circumference (MUAC) and body mass index-adjusted calf circumference (CC). Pearson correlation coefficients, receiver operating characteristics curve analysis, Youden's index, sensitivity (Se), specificity (Sp), and Cohen's kappa were used. RESULTS : Among 480 patients screened (51% male; mean age: 47.03 years, SD 14.87), 73% (n = 350) were at malnutrition risk. Of these, 54% (n = 189) were malnourished (GLIM criteria). MUAC and CC moderately correlated with ASMMI (r = 0.645; P<0.001 and r = 0.515; P<0.001 respectively). Optimal cut-offs for surrogates, with corresponding diagnostic accuracy, were: MUAC for ASMMI: 24.9 cm (area under the curve (AUC) = 0.857, Se = 85%, Sp = 74%) and CC for ASMMI: 29.1 cm (AUC = 0.819, Se = 73%, Sp = 83%). Substituting MUAC and CC for ASMMI at study-specific cut-offs - within the GLIM phenotypic criteria - was relatively valid (MUAC: kappa = 0.925, Se = 100%, Sp = 91%; CC: kappa = 0.849, Se = 100%, Sp = 91%). CONCLUSION : Within GLIM and using the reported cut-offs, MUAC reflects ASMMI. BMI-adjusted CC can replace low skeletal muscle mass. Valid, easy-to-use surrogates may enhance the feasibility of the GLIM diagnostic framework, particularly where resources are constrained.
Climate change risks and climate adaptation in agro-processing enterprises
Mazenda, Adrino; Obi, Ajuruchukwu; Kisaka-lwayo, Maggie; Antwi, Michael (Wiley, 2026-06)
While climate change research has focused mainly on primary agriculture, evidence shows that Agro-processing enterprises also face climate risks affecting resource availability and use. Using Partial Least Squares-Structural Equation Modelling (PLS-SEM), this study analysed how socio-demographic factors (sex, age, marital status, education, and training) influence participation in agro-enterprises and climate adaptation strategies among 113 agro-processing enterprises in Gauteng, South Africa. Results show that direct participation in Agro-processing does not significantly predict adaptation (β = 0.025), indicating profit-driven rather than resilience-oriented engagement. Education significantly enhances participation in Agro-processing (β = 0.325, 95% CI = [0.196, 0.457]) and adaptation (β = 0.325, 95% CI = [0.168, 0.477]), with a positive indirect effect (β = 0.106, 95% CI = [0.049, 0.173]). Sex negatively predicts participation (β = –0.181), showing higher female involvement, while other variables were insignificant. Policy interventions should integrate climate education, targeted training, and capacity-building initiatives to strengthen resilience among Agro-processing enterprises.
The potential of phytochemicals to overcome multidrug resistance in metastatic melanoma
Maphutha, Jacqueline; Twilley, Danielle; Dawood, Mona; Efferth, Thomas; Lall, Namrita (Wiley, 2026-01)
Metastatic melanoma is the most lethal form of skin cancer, accounting for most skin cancer-related deaths. Immunotherapies and targeted therapies have improved overall and progression-free survival rates in metastatic melanoma patients. The effectiveness of these therapies decreases due to multidrug resistance (MDR). In contrast to previous reviews, this review extensively highlights the hallmarks of MDR and strategies for reversal of MDR. The review also critically evaluates the challenges in clinical translation of phytochemicals for metastatic melanoma and strategies to overcome these challenges. This review also highlights the various gaps that exist in metastatic melanoma (e.g., vascularized organ-on-a-chip model has not been developed for melanoma which is largely influenced by angiogenesis). These gaps offer novel avenues that could be explored for clinical translation of phytochemicals.
Top-down drivers of savanna ecosystems promote bird foraging : effects of fire and large mammals on granivorous and insectivorous birds
Caminho, Jónata; Monadjem, Ara; André, Arquimedes; Bendana, Isaías Simão; Félix Mundoza, Diolinda; Da Graça Elias, Clementina; Greedes Fernando Marcolino, Iolanda; Massad, Tara Joy (Wiley, 2026-01)
ENGLISH : Fire and large mammal herbivores play major roles in shaping plant communities in savannas. However, the interactive effects of these drivers on other components of savanna biodiversity are less well understood. This study, conducted in Gorongosa National Park, Mozambique, tested the effects of fire and large mammals on the abundance and richness of foraging granivorous and insectivorous birds. We manipulated the presence of large mammals and early and late dry season burns and measured multiple aspects of grasses and woody plants as well as bird foraging. We modeled the abundance and richness of foraging birds in response to tree basal area, shrub abundance, grass biomass, grass cover, and grass richness in plots with and without large mammals and fire in the wet season prior to experimental burns, in the dry season following the burns, and in the subsequent wet season. Early and late dry season burns increased granivorous bird foraging in the wet season following the fires. Foraging insectivores increased in plots with cold burns 4 months after fire. The exclusion of large mammals generally reduced bird foraging, although positive effects of large mammal exclosures were detected when resources were limited, and fire and large mammals indirectly affected foraging by changing vegetation and therefore seed and arthropod food resources. Foraging was higher for both guilds where tree cover was greater, and foraging of insectivores increased with shrub cover and grass biomass and richness. These results emphasize the importance of considering fire-herbivore interactions for the conservation of savanna biodiversity.
Sustainable synthesis of energy-dense hydrochar from food waste blends via hydrothermal carbonisation : process optimisation and characterisation using response surface methodology
Pasipanodya, Danai; Seedat, Naadhira; Patel, Bilal; Roopchund, Rishen (Elsevier, 2026-05)
Hydrothermal carbonisation (HTC) was used to convert food waste (FW), comprising butternut waste (BW) and potato peels (PP), into hydrochar (HC). A central composite design (CCD) with response surface methodology (RSM) was used to investigate the effects of HTC temperature (140–300 °C), residence time (22–248 min), solid-to-liquid (S/L) ratio (1:11–1:15), and BW/PP ratio on HC yield, surface area (SA), and higher heating value (HHV). The quadratic model well-described the yield, SA, and HHV responses. The RSM-CCD maximum yield (40.22 %), SA (7.86 m2/g), and HHV (29.351 MJ/kg) was achieved at temperature of 204 °C, residence time of 131.39 min, S/L ratio of 1:12.89, and BW/PP ratio (0.5:0.5). The predicted responses were closer to experimental runs, proving good model reproducibility. Notably, temperature had the most significant influence on SA and HHV, except for yield, which depends greatly on the FW ratio. This is because at higher temperatures, volatiles are more effectively driven off, concentrating the carbon-rich components that enhance both SA and HHV. At the same time, the yield is more dependent upon the FW ratio due to variations in feedstock composition. Elemental analysis showed lower H/C and O/C ratios at elevated temperatures, indicating improved carbonisation typically leads to a higher HHV and improved fuel quality. SEM and FTIR confirmed the flask-like structures and functional groups, which can play a significant role in the adsorption capabilities of HC for pollutant removal. The valorisation of FW into adsorbents and biofuels represents a dual breakthrough, transforming waste management practices while simultaneously reducing greenhouse gas emissions. HIGHLIGHTS • Hydrothermal carbonisation of butternut and potato peel waste produces energy-dense hydrochar. • Response surface methodology optimised temperature, time, S/L ratio, and feedstock blend for yield, HHV, and surface area. • Optimised hydrochar at 220 °C, 113 min, 1:13 S/L ratio, and equal butternut and potato peel blend shows high HHV, surface area, and thermal stability.
From beginning to end : the synecology of tree-killing bark beetles, fungi, and trees
Six, Diana L.; Hammerbacher, Almuth; Trowbridge, Amy; Bullington, Lorinda (Wiley, 2026-02)
Over a century of research has revealed an amazing complexity of behaviours and physiological adaptations that allow tiny bark beetles to overcome large trees, sometimes resulting in outbreaks that kill millions of trees. Turning a tree into a home and successfully raising offspring involves constant interactions among the beetles, the tree, its microbiome, and the beetles' associated microbes, all influenced by abiotic factors that can determine success or failure. While we have learned much about these systems, substantial knowledge gaps remain. This synthesis aims to clarify and integrate current understanding, identify gaps, challenge long-held assumptions, and address interpretative issues that impede progress toward a holistic understanding of these systems. We advocate for expanding perspectives using synecological approaches to understand these complex systems better. We encourage expanding research into how colonization by the bark beetle–fungi complex influences subsequent tree decay and forest carbon dynamics. An explicit goal is to provide a comprehensive resource for new researchers while encouraging them to question established hypotheses and to explore new avenues of enquiry.
Innate resistance to African swine fever virus : current knowledge and future directions
Auer, Agathe; Blome, Sandra; Rozstalnyy, Andriy; Penrith, Mary-Louise (BioMed Central, 2026-01)
This review explores the biological basis and epidemiological implications of natural resistance to ASFV. It dispels the misconception that African wild suids are persistent virus reservoirs and clarifies the role of Ornithodoros ticks in virus maintenance and transmission. Resistance mechanisms appear multifactorial, potentially involving host genetics and immune responses. Genomic studies have begun identifying genes potentially linked to ASFV resistance, including in pigs from areas with more recent ASF incursions. Understanding and harnessing natural resistance is a promising avenue to develop ASFV-resilient pig populations, especially for smallholder farmers in resource-limited settings. While vaccines remain limited, promoting and protecting naturally resistant pigs offers an immediate, practical tool to mitigate the impact of ASF in endemic regions.

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