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First record of the white root rot fungus Dematophora necatrix on indigenous South African trees
(Springer, 2025-05) Balocchi, Felipe; Wingfield, Michael J.; Paap, Trudy; felipe.balocchi@fabi.up.ac.za
The soilborne fungus Dematophora (=Rosellinia) necatrix and causal agent of white root rot, has a wide host range that includes many tree species of economic importance. The pathogen has a worldwide distribution, including reports from commercial orchards in South Africa since the 1970s. During tree health surveys conducted as part of a sentinel plant project, we detected the pathogen on two symptomatic individuals from the indigenous South African tree species Diospyros whyteana and Noronhia foveolata subsp. major. Observed symptoms included wilting and root rot, with characteristic white mycelium present under the bark. Dematophora necatrix was isolated from both hosts and its identity confirmed by sequencing two gene regions (ITS and actin). Pathogenicity was confirmed through inoculation tests under semi-controlled conditions by inoculating the soil with bamboo sticks colonized with the fungus. Plants of both species developed similar symptoms to those observed naturally, and the fungus was successfully recovered from all symptomatic plants. This is the first record in South Africa of D. necatrix on indigenous species and outside of commercial orchards. Given the environmental threat posed we recommend the fungus is considered for regulation in South Africa.
Swallowing and oral-sensorimotor characteristics in a sample of young hospitalised children with severe acute malnutrition
(Wiley, 2025-05) Eslick, Casey Jane; Kritzinger, Alta M. (Aletta Margaretha; Graham, Marien Al; Kruger, Esedra
AIM : To describe swallowing and oral-sensorimotor characteristics in a sample of young hospitalised children with severe acute malnutrition (SAM).
METHODS : The Schedule of Oral-motor Assessment was used to compare oral-sensorimotor skills of 45 hospitalised patients with SAM (M = 15.98 months; SD = 8.03), to pairwise-matched controls (M = 15.96 months; SD = 8.08). Participants were matched for age, gender, TB, HIV-status, socio-economic status including maternal education, paternal employment, housing and transport access. Caregivers reported demographic information, feeding practices and behaviours during feeding.
RESULTS : In comparison to controls (n = 6; 13.3%), participants with SAM (n = 25; 55.6%) presented with significantly more oral-sensorimotor difficulties (p < 0.001), across all consistencies except liquids from the trainer cup and bottle. Difficulties included jaw opening and stabilisation, tongue and lip control for chewing, bolus formation and transport, sustained bite and uncoordinated swallowing. Delayed sitting development significantly correlated with uncoordinated swallowing and head extension on puree and cup drinking, and multiple swallows on puree and semi-solids. Force-feeding and slow swallow initiation in semi-solids significantly correlated. Disruptive feeding behaviours and higher levels of food refusal at the beginning of meals were reported. Clinical signs of aspiration were identified.
CONCLUSIONS : Oral-sensorimotor dysfunction and possible aspiration were observed in 55.6% of participants with SAM. Safe swallowing function for overall health and nutritional recovery is emphasised. Under-identification of oral-sensorimotor difficulties, lack of referral to speech-language therapists and disruption to continuity of care warrants further research.
Supernumerary teeth : a pictorial review and revised classification
(Elsevier, 2025-05) Davidson, Christy Lana; Smit, Chane; Nel, Sulette; christy.davidson@up.ac.za
Current literature regarding supernumerary teeth poses the risk of confusion as ambiguity in the terminology and classification of supernumerary teeth permits differing interpretations.
Uncertainty in this regard distorts data on the true incidence and prevalence of supernumerary teeth. This pictorial review provides an overview of the current understanding regarding the development of supernumerary teeth, their positional and morphological classification, and eruptive alterations. We highlight the ambiguity in defining supernumerary teeth and propose an updated classification for the description of these teeth.
Nurse leaders' perceptions of followership development needs : a descriptive qualitative study
(Wiley, 2025-04) Mamba, Welile Magnificent; Fourie, Willem; Heyns, Tanya; u17284229@tuks.co.za
INTRODUCTION : Followership is a critical aspect of leadership because, without followers, there can be no leaders. To be successful, organizations must develop high-performance, self-developed, and self-led followers with specific values. However, organizations have traditionally prioritized developing leaders, leaving out followers in the development equation. Followership development allows nurses to learn how to work effectively in teams, fostering teamwork skills.
AIM : To explore nurse leaders’ perceptions of followership development needs.
MATERIALS AND METHODS : A descriptive qualitative design was used. Data were collected via face-to-face, semi-structured, in-depth interviews with 10 purposively selected nurse leaders (middle and top management). The interviews were audio-recorded, transcribed verbatim, and analyzed via Braun and Clarke’s approach.
FINDINGS : Participants emphasized the need for followership education for nurses. Followership should be incorporated into undergraduate nursing curricula and in-service training. Additionally, participants verbalized the need for a followership development program that should train nurse followers in communication, inter-professional collaboration, decision-making, team building, teamwork, and leadership. The participants suggested that followership could be developed by providing incentives for good followership behavior and conducting periodic performance appraisals.
CONCLUSION : The participants emphasized the importance of a followership development program, which may enhance the relationship between nurse leaders and followers and contribute to positive patient outcomes. Future research needs to develop programs to develop nurses who are followers.
IMPLICATIONS FOR NURSING MANAGEMENT : Developing followers in a hospital setting is critical. Understanding needs and what a followership program should include assists nurse leaders in planning and implementing relevant programs.
GARCHX-NoVaS : a bootstrap-based approach of forecasting for GARCHX models
(Wiley, 2025) Wu, Kejin; Karmakar, Sayar; Gupta, Rangan
In this work, we explore the forecasting ability of a recently proposed normalizing and variance-stabilizing (NoVaS) transformation with the possible inclusion of exogenous variables in GARCH volatility specification. The NoVaS prediction method, which is inspired by a model-free prediction principle, has generally shown more accurate, stable and robust (to misspecifications) performance than that compared with classical GARCH-type methods. We derive the NoVaS transformation needed to include exogenous covariates and then construct the corresponding prediction procedure for multiple exogenous covariates. We address both point and interval forecasts using NoVaS type methods. We show through extensive simulation studies that bolster our claim that the NoVaS method outperforms traditional ones, especially for long-term time aggregated predictions. We also exhibit how our method could utilize geopolitical risks in forecasting volatility in national stock market indices. From an applied point-of-view for practitioners and policymakers, our methodology provides a distribution-free approach to forecast volatility and sheds light on how to leverage extra knowledge such as fundamentals- and sentiments-based information to improve the prediction accuracy of market volatility.