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We acknowledge the existing educational inequalities that South Africa faces as a result of differences in developmental and equal educational opportunities. The aim with this study was to investigate the role of non-cognitive learning performance variables that affect the learning performance and success of secondary-school learners. Data were collected from a sample of 395 Grade 9 learners. The proposed learning performance structural model was empirically evaluated by using various instruments and was analysed by means of structural equation modelling. The results indicate statistically significant positive relationships between learning performance and cognitive engagement, learning performance and grit, cognitive engagement and conscientiousness, grit and learning motivation, grit and cognitive engagement, learning motivation and parental quality, learning motivation and tenacity, learning motivation and cognitive engagement, and conscientiousness and resilience. Both tenacity and parental quality acted as moderators of the relationship between environmental unfavourableness and cognitive engagement. The selection of variables was more effective in explaining variance in cognitive engagement than in learning performance. The results of the study could be used to facilitate cognitive engagement as a pivotal variable in learning success among secondary-school learners.

The aim of this study was to validate the Teacher Stress Inventory (TSI) for use in a South African context. The process of scale validation also sheds significant light on this culturally diverse group of participants' levels of psychological wellbeing and physical health, and its association with the level of stress that teachers reported. Using a cross-sectional survey design, Caucasian (n = 209) and African (n = 200) educators' subsiding in the North-West Province of South Africa, completed the TSI, together with a number of self-report and physiological measures of stress and well-being. In contrast to the five factors of the TSI identified in US samples, statistical analysis yielded a two-factor model (i.e. "General circumstance-related stress and Learner-related stress") with satisfactory reliability indices. Significant correlation with measures of psychological and physiological health also reflected positively on the criterion-related validity of the scale. The TSI proved to be a useful, brief self-report questionnaire for the assessment of teacher stress in this cohort of South African teachers.

Student engagement is crucial for learning, especially in online learning. For a student to be a successful online learner, they need to engage socially and collaboratively through their behaviours, emotions and cognition. This paper discusses an accounting module of a fully online degree where engagement was purposely integrated using an engagement framework. An action research design was followed to determine the degree of engagement within the module and to improve on it. The findings indicated that incorporating five forms of engagement into the module was positively received by students and resulted in more students successfully completing the module. Student reflections showed that the module was cognitively engaging, that personal preference will guide social engagement and that working collaboratively will always be a challenge. Where, due to COVID-19, entire programmes need to convert to online learning, the findings of this study, could be implemented to ensure the continued engagement of students.

For higher education institutions to produce graduates capable of contributing to society and the economy in a productive manner, educational emphasis is placed on the development of critical thinking. The above necessitates that higher education institutions are able to engage in responsive curriculum design and delivery for enhanced student success and access. Public Administration programmes focus on equipping students to work within the broader government sector, able and capable of delivering public functions responsive to the needs of society. Literature suggests that there are a number of factors which influence the success ratio of any undergraduate programme in the South African context, including, inter alia, increased enrolments, student--staff ratios and the overall decline of professional and intellectual life in the country. Further complicating matters are classes too big to be participatory and crammed syllabi preventing in-depth discussions. The notion of embedding academic literacy development in curriculum design through a scaffolded approach aims to influence the academic performance of students through engaged and active learning in order to attain a higher level of achievement as well as benefit from the process of scaffolding. The research comprises a mixed method approach using a case study of the first-year students enrolled for a Public Administration degree. Data collected included an analysis of 2015, 2016 and 2017 student cohorts in: determining their academic literacy level upon registration (set as a baseline before any academic literacy intervention); tracking their academic performance through their formative and summative assessments (through a scaffolded approach); and reflecting upon their learning through their completion of a semi-structured survey. The research intends to argue that the use of a scaffolded approach to learning enhances epistemic access, which sees students moving beyond propositional, or foundation knowledge to epistemic or reflexive knowledge.

Objective: to investigate the predictors of vitamin D (vitD) status of undernourished and well-nourished children aged under five years in the North West Province of South Africa. Design: this cross-sectional study assessed sociodemographic data, nutritional supplement intake, vitD-rich food consumption, and sunlight exposure via a structured questionnaire. Venous blood samples were collected to evaluate vitD, iron, and inflammatory markers. Setting: the maternal and child wellness departments of six community clinics in the JB Marks Municipality. Participants: 121 undernourished and 51 well-nourished children, 6–59 months old. Results: The prevalence of serum 25(OH)D < 30 ng/ml was 20.3%, 19.9%, and 21.6% in the total, undernourished, and well-nourished groups, respectively. The total mean 25(OH)D concentration was 38.41 ± 9.64 ng/ml. Age showed a negative association trend with 25(OH)D in the well-nourished group (β: −0.172, 95% CI −0.353, 0.010, p = 0.063), while household income was inversely associated with 25(OH)D (β = −1.86, 95%CI = −2.99, −0.733, p = 0.001) in the total group. Among the undernourished children, iron-deficiency anaemia (IDA) was associated with almost five times greater odds for 25(OH)D < 30 ng/ml (OR: 4.646, 95% CI 1.339, 16.123, p = 0.016). Intake of vitD supplements, therapeutic foods, multivitamins, and formula milk was associated with significantly higher 25(OH)D concentrations and was adjusted for in subsequent analyses. Additionally, consumption of eggs more than once a month was associated with higher 25(OH)D levels in the well-nourished children aged 24–59 months. Nutritional status, inflammation, and sunlight exposure were not associated with 25(OH)D concentrations. Conclusion: vitD insufficiency exists in both the undernourished and the well-nourished. Age, egg consumption, and IDA should be considered in the correction of vitD insufficiency in children. Trial registration: Pan African Clinical Trial Registry identifier: PACTR202110646172601.. [ABSTRACT FROM AUTHOR]

IMPACT: The authors explain why municipal capacity should be significantly improved for the successful implementation of audit recommendations by the Auditor-General of South Africa (AGSA). Municipalities need robust systems of financial delegation, oversight and internal controls. Such systems should make provision for record-keeping, financial risk assessments, processing and reconciling of financial transactions, regular, accurate, and complete financial and performance reports, as well as the reviewing and monitoring of compliance with applicable legislation. Audit action plans must be developed to outline key details. In addition, municipal councils should adopt a consequence management and accountability framework to enforce due diligence and compliance with council resolutions. Support mechanisms, such as disciplinary boards and municipal misconduct regulations, can add significant value in this regard. The lessons in this article have value beyond South Africa and particularly for senior local government officials, members of audit and risk committees, internal auditors, members of political oversight committees, and senior managers of national and provincial government overseeing municipal financial affairs. This study is a situational analysis of municipal audit outcomes and key audit findings of the Auditor-General of South Africa (AGSA). It draws on desktop and document analyses, and an empirical survey conducted among randomly sampled local districts and metropolitan municipalities. It delves into the institutional layers within municipalities at governance and administrative levels, shedding light on the responsiveness, accountability, and measures taken to address audit findings. This article concludes with an exploration of remedial measures to best address the AGSA's findings, seeking to contribute to the development of effective solutions for municipalities to improve their financial accountability and responsiveness. As such, it contributes to the existing corpus of knowledge by providing a guide for municipalities to translate theoretical concepts of financial oversight into actionable steps. [ABSTRACT FROM AUTHOR]

This article reports on the qualitative aspects of a study that examined whether introducing a "Problem-based Learning" ("PBL") approach in a one-year foundation programme can create conditions for learners to develop and sustain self-directed learning skills. This interpretive constructivist case study was located in evaluation research. Data were collected by means of classroom observations and interviews with 35 students and 14 former students. Findings indicated that introducing students to a PBL approach did promote more meaningful learning patterns, typified by processing the subject matter critically and self-regulating learning processes. The sustainability of the meaning-directed learning skills was questionable if student beliefs in the approach did not support the activities employed. Introducing PBL into a foundation programme can develop self-directed learning skills in students and set in motion a process of growth towards lifelong learning.

Poor iron status is detrimental to physical and cognitive performance in adolescents. Due to the limited studies investigating the association between iron status and physical fitness components in adolescents from low- and middle-income countries, we aimed to determine the association of iron status with selected physical fitness components in South African adolescents. A cross-sectional study design, including 178 adolescents (102 girls and 76 boys) from the Physical Activity and Health Longitudinal Study (PAHLS), was followed. Height and weight were measured to calculate the body mass index (BMI). Subsequently, WHO BMI-for-age-specific categorised body fatness. Cardiorespiratory fitness was determined with a 20-m shuttle run test ( V ˙ O 2 max ), and lower-body explosive power by the standing broad jump (SBJ). Fasting haemoglobin (Hb) and ferritin were analysed from blood samples. Correlation analyses determine the association between iron status, explosive power and cardiorespiratory fitness. Of the 178 participants, 18.5% (n = 33) had low Hb, and 14% (n = 25) iron deficiency without anaemia. Significant positive correlations were found between the selected physical fitness components, ferritin, and Hb. In boys, a positive association was found between Hb and SBJ (r = 0.30, p = 0.006), whilst in girls, positive associations were found between ferritin (r = 0.25, p = 0.04) and SBJ, and Hb with both SBJ (r = 0.21, p = 0.03) and V ˙ O 2 max (r = 0.32, p = 0.001). Hb concentration remained associated with V ˙ O 2 max and SBJ in girls after adjustment for age, whilst in boys, Hb concentration was associated with SBJ. Higher iron status in South African adolescents is associated with higher lower-limb explosive power and cardiorespiratory fitness. We suggest monitoring of haematological parameters, and interventions to improve the iron status of South African adolescents. [ABSTRACT FROM AUTHOR]

The New Zealand bottlebrush, Metrosideros excelsa (Myrtaceae), was introduced into South Africa in the 1940s as an ornamental plant and subsequently naturalized in coastal parts of the Cape Floristic Region. Knowledge of M. excelsa's propagule pressure and response to fire in South Africa can inform evaluation of the species' invasion potential and management. We assessed M. excelsa's canopy and soil seed banks in burnt and unburnt stands; and post‐fire regeneration via reseeding and resprouting in relation to fire severity and tree size. Soil seed banks were assessed using an emergence technique, but no seedlings emerged from soil collected under burnt or unburnt plants suggesting that the species does not maintain a viable soil‐stored seed bank or germination triggers were not met (though unlikely). The annual seed crop in the canopies of unburnt trees was approximately 0.5–23 million seeds per tree. Viability, assessed through tetrazolium stain testing, of canopy‐borne seeds on unburnt trees was 18%, whereas a canopy fire, ranging in severity from low to extreme, killed all canopy‐borne seeds. Fifteen months post‐fire, the seedling to pre‐fire (live) tree ratio was 0.01, whereas 43% of burnt trees survived via basal resprouting. Fire severity had a non‐linear effect on tree survival (survival was highest after medium and high fire severity and lowest after low and extreme fire severity), while larger trees were more likely to survive fire. These results suggest that even low‐severity (safe) burning may be a useful control measure as it kills canopy‐borne seeds and causes substantial mortality, particularly of smaller trees. An opportunistic evaluation of an uncontrolled (no comparison with untreated individuals) foliar herbicide application to post‐fire resprouting individuals also showed considerable (91%) mortality. However, rigorous herbicide trials (also with herbicide in conjunction with burning) are required to inform the management of M. excelsa. [ABSTRACT FROM AUTHOR]

This article reports on one of the objectives of a larger study aiming at the development of an adolescent risk-behavior management program for foster parents. The objective relevant to this article entailed the exploration of parenting behaviors and attitudes of parents fostering adolescents presenting with risk behavior. The respondents were recruited from the clientele of designated welfare organizations in the North West Province of South Africa. A quantitative survey using the multi-dimensional Parental Style Dimension Questionnaire (PSDQ) was administered to a purposive sample of 150 respondents. A response rate of 64.5% was achieved, with only foster mothers participating in the study. Data analysis was done by the Statistical Consultation Services of the North-West University (Potchefstroom Campus) using IBM SPSS Statistics Version 25, Release 25.0 SPSS. In addition, T-Tests and ANOVAs were used to test the hypothesis at a 0.05 level of significance and Spearman's correlations examine correlations between sub-scale scores and biographical data. Sub-scales of the PSDQ were tested for internal consistency reliability and reasonable coefficients were rendered, except for the permissive parenting style scale that was excluded from analysis. The results showed a significant, positive correlation between authoritative and authoritarian parenting styles amongst the respondents. Parental attitudes and responses to risk behavior significantly affected their actual behavior towards fostered adolescents presenting with risk behavior. The researchers concluded that consideration of parenting styles in the foster care relationship context will greatly determine the nature of further interventions. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. (Asteraceae), commonly known as famine weed in South Africa, is one of the most invasive weeds worldwide, accountable for losses to biodiversity, agriculture, the economy, and the health of livestock and human beings. The spread of this weed is not easy to manage or reverse. With globalization, trade, and human movement, it will continue to spread, allowing its range to expand into new areas. This weed has serious adverse effects on rangeland and agricultural crop production. Because of its unique characteristics, its invasiveness and competitive success rates are attributed to its high reproductive ability, fast growth rate, tolerance to environmental stresses, climate change adaptability, allelopathic potential, and unpalatability to animals. Parthenium hysterophorus dominates diverse habitats by spreading quickly as a contaminant of grain and other crop products and through farm machinery. It is widely distributed and has become problematic in various countries, including South Africa. It has successfully invaded several provinces in the country since its introduction in 1880. Since plant invasions are not universal, this study aimed to review research that has been conducted on the aggressive weed P. hysterophorus to understand the ecological characteristics that enable its successful establishment, the economic costs associated with its detrimental impacts, and to briefly assess knowledge gaps to improve its management strategies. [ABSTRACT FROM AUTHOR]

Phlyctinus callosus and P. xerophilus (Coleoptera: Curculionidae) are two cryptic species of native entimine weevils, previously grouped together under the P. callosus sensu lato concept, that are pests of economic importance to the deciduous fruit and vine industry in the Western Cape province of South Africa. Laboratory bioassays were conducted using entomopathogenic fungi (EPF) isolates of Beauveria and entomopathogenic nematodes (EPNs), Heterorhabditis indica and Steinernema yirgalemense, to determine differences in susceptibility of adult P. callosus and P. xerophilus to potential biological control agents. The test arena used was 24‐well bioassay plates with an inoculation rate of 200 infective juveniles (IJs)/insect for EPNs and 5 × 105 conidia/insect for EPF. Insects were inoculated using a 12.7 mm filter paper impregnated with 50 μL of entomopathogen suspension. Infection was determined after 96 h incubation for EPNs through dissection of cadavers. Insects inoculated with EPF were incubated in the wells for 18 days and mortality recorded daily. Cadavers were surface sterilized and observed for overt mycosis. Differential susceptibility between P. callosus and P. xerophilus was observed in EPF but not in EPN bioassays. Differential susceptibility to EPF could be due to methodology. Low adult weevil pathogenicity was found for all entomopathogens, with variable results obtained from different bioassay batches. [ABSTRACT FROM AUTHOR]

Summary: Considerable progress has been made in the surveying, taxonomy, screening, mass production and formulation of entomopathogenic nematodes (EPN) and their associated symbiotic bacteria in South Africa. Steinernema yirgalemense isolate 157-C is one of the most promising native EPN candidates with regards to virulence, its broad insect-host spectrum, and can be readily mass-produced and formulated into a commercial product. The banded fruit weevils, Phlyctinus callosus sensu stricto and Phlyctinus xerophilus , previously grouped together under the Phlyctinus callosus sensu lato species concept, are native entimine weevils of economic importance to deciduous fruit, grapevine and berries in the Western Cape province of South Africa. This study investigated potential differences in baseline susceptibility of larvae and pupae of the two weevil species to S. yirgalemense in laboratory screenings. The test arena used was 24-well bioassay plates, with an inoculation concentration of 200 infective juveniles (IJ) insect−1 for larvae and 100 IJ insect−1 for pupae. Infection was determined 48 h and 96 h after inoculation. Field-efficacy of S. yirgalemense , applied at a concentration of 60 IJ cm−2, against larvae of the two weevil species was determined in an ecologically relevant semi-field trial. In all cases in vitro mass-produced IJ of S. yirgalemense were used. No baseline differential susceptibility between P. callosus and P. xerophilus larvae was obtained in laboratory screenings. Phlyctinus pupae were approximately twice as susceptible compared to larvae, with significant differences between bioassay batches. Approximately 45% control of P. xerophilus larvae was obtained after 96 h of exposure to S. yirgalemense in the field, differing significantly from the control and P. callosus treatment. Low levels of Phlyctinus larval infection by native EPN (confirmed as Heterorhabditis bacteriophora from one P. xerophilus cadaver) occurred in both control and EPN treatment groups under field conditions. [ABSTRACT FROM AUTHOR]

Road safety education is a complex phenomenon which should be viewed holistically if taken into account the interconnectedness of education, infrastructure and enforcement. Effective road safety education is specifically important for learners in the Further Education and Training (FET) band, as they are active contributors to a community. The greatest criticism against road safety education is that it is aimed at changing learners' knowledge about the subject, but not necessarily influencing their attitudes as road users. The aim of this discussion article is to explore a strategy to integrate road safety education into the formal curriculum of specifically schools responsible for the FET band. By applying the desktop research method, the article conceptualises what the specific purpose of the FET band is and what the possible focus of road safety education and training should be. The article then explores international common practices in road safety education and training, and considers the necessary synergy between education, engineering and enforcement. The article uses secondary data collected from documents which are then thematically analysed. A coordinated and comprehensive education and training strategy is needed, facilitating partnerships in various sectors to implement such education in the FET band, in multidisciplinary ways, in a contextualised curriculum.

Resilience pertains to an individual's ability to withstand, adapt, and recuperate from adversity and stress. As the world grapples with unprecedented challenges such as the COVID-19 pandemic, understanding the relationship between resilience and psychological well-being becomes essential. Preliminary observations suggest that those with a higher resilience tend to have better psychological well-being, indicating a possible symbiotic relationship between the two. This study was structured using a cross-sectional survey design. A convenience sampling technique was employed, including 631 respondents in South Africa. Data collection took place between June 11 and July 9, 2022, facilitated through a Google Forms questionnaire. This questionnaire encompassed various instruments, namely a biographical questionnaire, the CD-RISC 10, the WHO Well-being Index, the FACIT-Sp-12, and the PMHS. The findings from the collected data highlighted a strong correlation between resilience and overall well-being during the COVID-19 pandemic. This elevation in resilience can be instrumental in augmenting psychological well-being. As such, interventions or programs aimed at enhancing individual and community well-being might benefit from incorporating elements that bolster resilience, especially during periods of global adversity. [ABSTRACT FROM AUTHOR]

We acknowledge the existing educational inequalities that South Africa faces as a result of differences in developmental and equal educational opportunities. The aim with this study was to investigate the role of non-cognitive learning performance variables that affect the learning performance and success of secondary-school learners. Data were collected from a sample of 395 Grade 9 learners. The proposed learning performance structural model was empirically evaluated by using various instruments and was analysed by means of structural equation modelling. The results indicate statistically significant positive relationships between learning performance and cognitive engagement, learning performance and grit, cognitive engagement and conscientiousness, grit and learning motivation, grit and cognitive engagement, learning motivation and parental quality, learning motivation and tenacity, learning motivation and cognitive engagement, and conscientiousness and resilience. Both tenacity and parental quality acted as moderators of the relationship between environmental unfavourableness and cognitive engagement. The selection of variables was more effective in explaining variance in cognitive engagement than in learning performance. The results of the study could be used to facilitate cognitive engagement as a pivotal variable in learning success among secondary-school learners. [ABSTRACT FROM AUTHOR]

The combined sandwich-ELISA (s-ELISA; VitMin Lab, Germany) and the Quansys Q-Plex™ Human Micronutrient Array (7-Plex) are multiplex serum assays that are used to assess population micronutrient status in low-income countries. We aimed to compare the agreement of five analytes, α -1-acid glycoprotein (AGP), C-reactive protein (CRP), ferritin, retinol-binding protein 4 (RBP4) and soluble transferrin receptor (sTfR) as measured by the 7-Plex and the s-ELISA. Serum samples were collected between March 2016 and December 2017. Pregnant women (n 249) were recruited at primary healthcare clinics in Johannesburg, and serum samples were collected between March 2016 and December 2017. Agreement between continuous measurements was assessed by Bland–Altman plots and concordance measures. Agreement in classifications of deficiency or inflammation was assessed by Cohen's kappa. Strong correlations (r > 0·80) were observed between the 7-Plex and s-ELISA for CRP and ferritin. Except for CRP, the 7-Plex assay gave consistently higher measurements than the s-ELISA. With the exception of CRP (Lin's ρ = 0·92), there was poor agreement between the two assays, with Lin's ρ < 0·90. Discrepancies of test results difference between methods increased as the serum concentrations rose. Cohen's kappa for all the five analytes was < 0·81 and ranged from slight agreement (vitamin A deficiency) to substantial (inflammation and Fe deficiency) agreement. The 7-Plex 1.0 is a research and or surveillance tool with potential for use in low-resource laboratories but cannot be used interchangeably with the s-ELISA. Further optimising and validation is required to establish its interchangeability with other validated methods. [ABSTRACT FROM AUTHOR]

Background: Antenatal iron deficiency and anaemia are associated with gestational hypertension and diabetes mellitus, but so are elevated iron stores and haemoglobin. In South Africa, pregnant women receive routine iron supplementation regardless of iron status. Aim: This study aimed to assess associations of antenatal iron status and anaemia with blood pressure in pregnant women in urban South Africa. Secondary to this, associations with heart rate, fasting glucose and glucose tolerance were also investigated. Setting: Johannesburg, South Africa. Methods: A total of 250 pregnant women, aged 27 (24--32) years, were recruited using consecutive sampling. The authors measured biomarkers of iron status and anaemia at < 18 and ± 22 weeks', blood pressure and heart rate at ± 36 weeks', and fasting glucose and glucose tolerance between 24 and 28 weeks' gestation. Associations were determined using multivariable regression models adjusted for confounders. Results: The odds of prehypertension in late pregnancy among women with anaemia at ± 22 weeks' gestation were three times higher than among women without anaemia (odds ratio [OR]: 3.01, 95% confidence interval [CI]: 1.22, 7.42). Participants with anaemia at ± 22 weeks' gestation had 2.15 times higher odds of having elevated mean arterial pressure than women without anaemia (OR: 2.15, 95% CI: 1.01, 4.60). Conclusion: Anaemia at mid-pregnancy could be a predictor of hypertensive disorders in pregnancy. The cause of antenatal anaemia may need further investigation apart from iron deficiency. The effective management of anaemia in pregnant women living in urban South Africa remains a challenge. Contribution: This study provides evidence about the health impact of pregnant women regarding antenatal supplementation practices in South Africa. [ABSTRACT FROM AUTHOR]

To describe the evolution of swallowing and feeding abilities of neonates with hypoxic-ischaemic encephalopathy (HIE) during hospitalisation. A longitudinal cohort study was used. Twenty-nine participants (median age 39.0 weeks [IQR = 2.0 weeks]) with mild (n = 7), moderate (n = 19) and severe (n = 3) HIE were included. Clinical swallowing and feeding assessments were conducted at introduction of oral feeds and at discharge using the Neonatal Feeding Assessment Scale (NFAS). Videofluoroscopic swallow studies (VFSS) supplemented the NFAS before discharge. Approximately two thirds of participants showed symptoms of oropharyngeal dysphagia (OPD) during initial NFAS and VFSS. Significantly fewer OPD symptoms occurred at discharge NFAS (p = 0.004). Endurance during non-nutritive sucking (p < 0.001) and nutritive sucking (p < 0.001) significantly improved. Nine participants (31.0%) demonstrated penetration or aspiration. Most aspiration events were silent (60%). Instrumental assessment identified pharyngeal phase dysphagia more effectively than bedside evaluation. High proportions of participants displayed OPD symptoms regardless of HIE severity. The correlation between OPD severity and the length of hospitalisation (p = 0.052) was not significant. All grades of HIE should be considered for early intervention by speech-language pathologists before discharge. Findings may be valuable to neonatal feeding teams. [ABSTRACT FROM AUTHOR]

Objective: To conduct a comprehensive systematic review and meta-analysis of the available literature on the anthropometric nutritional status of South African infants and children, 0–18 years old and to report on trends of changes in nutritional status over the period 1997–2022. Design: Systematic review and meta-analysis. Setting: Review of the available literature on the anthropometric nutritional status of South African infants and children, 0–18 years old, over the period 1997–2022. Participants: South African infants and children, 0–18 years old. Results: Only quantitative data from ninety-five publications that described the nutritional status in terms of anthropometry were included. Most recent studies applied the WHO 2006 and 2007 definitions for malnutrition among children 0–5 years old and 5–19 years old, respectively. Meta-analysis of all prevalence data shows the highest stunting prevalence of 25·1 % among infants and preschool children, compared to 11·3 % among primary school-age children and 9·6 % among adolescents. Furthermore, the overweight and obesity prevalence was similar among children younger than 6 years and adolescents (19 %), compared to 12·5 % among primary school-age children. In national surveys, adolescent overweight prevalence increased from 16·9 % in 2002 to 23·1 % in 2011. Meta-regression analysis shows a decrease in stunting among children 6–18 years old and an increase in combined overweight and obesity in the 10–19 years age group. Conclusion: The double burden of malnutrition remains evident in South Africa with stunting and overweight/obesity the most prevalent forms of malnutrition among children. [ABSTRACT FROM AUTHOR]

Summary: The bacterial strain SF857 was isolated from the entomopathogenic nematode, Steinernema bakwenae SF857, found in soil samples of St Lucie cherry, a species of cherry tree, from the Muriti farm, close to Kroondal (25°44′E, 59°99′S) in the northwest province of South Africa. Strain SF857 is Gram-negative, catalase and oxidase-negative, and lecithinase-positive. Strain SF857 shared the highest 16S rRNA gene sequence similarity (97.7%) with the type strain of Xenorhabdus ishibashii. However, a comparison of housekeeping gene sequences showed that strain SF857 grouped closer to X. griffiniae , X. ehlersii and X. thuongxuanensis than to X. ishibashii. Digital DNA-DNA hybridisation (dDDH) between strain SF857 and all Xenorhabdus spp. is less than the 70% species threshold, confirming that the strain belongs to a separate species. Furthermore, the biochemical characteristics of strain SF857 differ from other Xenorhabdus spp. Based on these findings, strain SF857 represents a novel species within the genus Xenorhabdus , for which the name Xenorhabdus bakwenae sp. n. (type strain SF857T) is proposed. Pathogenicity bioassays with last-instar Cydia pomonella showed S. bakwenae to be highly virulent, with potential use as a biocontrol agent in apple orchards. [ABSTRACT FROM AUTHOR]

Summary: Optimising the in vitro liquid mass production process for entomopathogenic nematodes (EPN) is a critical step in the development of a cost-effective EPN biopesticide product. Recording the nematode population and growth dynamics in an Erlenmeyer shake flask environment is essential to gaining a better understanding of which factors may influence the final yield. Although infective juvenile (IJ) inoculum concentration has previously been studied, no consensus yet exists as to whether it influences the final yield. This study sought to determine the impact of IJ inoculum concentration and timing on the recovery, growth and yield of the South African EPN isolate of Steinernema yirgalemense in shake flasks. The results indicated that the IJ inoculum concentration positively affects the final IJ yield of 2.88 × 155 IJ ml−1. Moreover, at higher IJ inoculum concentrations, a higher number of reproductive females and males are produced, when recovery percentages were similar. The lowest IJ inoculum concentration treatment was also the only treatment to show signs of an unwanted second generation in the final yield. The IJ inoculation timing trials confirmed that once the bacterium, Xenorhabdus indica , has ended the exponential growth phase and entered the stationary phase, it is ideal to then inoculate the IJ. However, it was found that the S. yirgalemense can be inoculated into the X. indica bacteria solution after 36 h of growth, instead of after 44-48 h. These trials demonstrated the need for further optimisation to produce consistent yields of the highly pathogenic South African EPN isolate of S. yirgalemense. [ABSTRACT FROM AUTHOR]

The Pied Kingfisher Ceryle rudis is a fishing kingfisher that employs two hunting modes. The bird can either hunt from a perch or hover and then dive into the water. The former method is energetically cheap but limits prey searching to the area below the perch, whereas hovering is costly but gives access to feeding areas that lack perches. This exploratory study examined how the provision of artificial perches influences the frequency of hover and perch hunting. In the hunting tracts with additional perches, 82% of 175 hunts were successful, but there was no correlation between the success of hunts and the presence of perches. However, hunting rates in tracts with extra perches were four-times higher than in control tracts. These results suggested that even though more perches did not improve the hunting success of Pied Kingfishers, the birds could increase their hunting rates, which probably enabled them to catch their daily fish requirements in a shorter time. [ABSTRACT FROM AUTHOR]

This study investigated the use of a limit equilibrium model to simulate the time-dependent scaling of hard rock pillars. In the manganese bord and pillar mines in South Africa, extensive scaling is observed for pillars characterised by a high joint density. It appears that the scaling occurs in a time-dependent fashion. Evidence for this is the ongoing deterioration of pillars in old areas, even after the pillars are reinforced with thin spray-on liners. Monitoring of selected pillars were conducted in an attempt to quantify the rate of time-dependent scaling. Contrary to expectations, almost no additional scaling was recorded for the pillars during a 3-month monitoring period. The scaling distance for pillars of different ages could be measured and it seems as if most of the scaling occurred soon after the pillars are formed. Only a limited amount of additional time-dependent scaling seems to occur after this. Numerical simulations of the time-dependent scaling were conducted using a displacement discontinuity code and a limit equilibrium constitutive model. The postulated exponential decay of the failed rock mass strength at the edges of the pillars resulted in simulated behaviour that is qualitatively similar to the underground observations. The results from this study are encouraging and the method can be used to investigate the long-term stability of bord and pillar excavations. Further work is required to improve on the calibration of the model and to better quantify the rate of scaling of the underground pillars. Highlights: Time-dependent scaling gradually reduces the strength of pillars. This paper presents a study of this behaviour in a hard rock bord and pillar mine. A numerical modelling approach to simulate time-dependent pillar failure, on a mine-wide scale, is described in the paper. It consists of a displacement discontinuity boundary element method with a time-dependent limit equilibrium model. The behaviour of the hard rock pillars in the manganese mines in South Africa is used to test the proposed model. It provides valuable data for researchers interested in case studies of time-dependent pillar strength. The proposed modelling methodology seems valuable to design layouts where long-term stability is a requirement. Although the focus in this paper is on hard rock mines, it can also be used for coal pillars. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the association between maternal postpartum depressive symptoms, household demographic, socioeconomic, and infant characteristics with infant physical growth, and how these factors correlate to determine latent factors. This study was based on the baseline data of a 6-month randomised controlled trial aimed at providing an egg a day to infants aged 6 to 9-months from a low socioeconomic community in South Africa. Information collected on household demographic, socioeconomic, and infant characteristics was by face-to-face structured interviews, and trained assessors took anthropometric measurements. The Edinburgh Postnatal Depression Scale (EPDS) was used to assess maternal postpartum depressive symptoms. The analysis was based on 428 mother-infant pairs. Total EPDS score and its subscales score were not associated with stunting or underweight risk. However, a three- to four-fold increased risk of stunting and underweight, respectively was observed for premature birth. Low birthweight was associated with an estimated six-fold increased risk of underweight and stunting. Being female was associated with about 50% reduced risk of stunting and underweight. In conclusion, more robust studies are needed to substantiate these findings, with more awareness creation on the consequences of LBW and prematurity on the physical growth of infants from resource-limited settings. [ABSTRACT FROM AUTHOR]

Invasive alien species represent one of the main threats to biodiversity and species extinction. This is the case for the genus Prosopis, among which Prosopis velutina is the most invasive and common tree species along the Molopo River in the North-West Province, impacting native plant communities. However, its impact on the composition and diversity of native woody species remains poorly investigated in the area. Thus, this study aimed to assess the impact of P. velutina on native woody plant composition and diversity across three sites along the Molopo River. At each site, five quadrats of 20 × 20 m2 were randomly established in invaded and adjacent uninvaded stands. A comparative methodological approach was adopted, and the woody plants in invaded and uninvaded stands with similar site conditions were sampled. The results showed that native woody species density differed significantly (p < 0.05) between invaded and uninvaded stands, except for Bray sites, where there was a marginal difference (p = 0.6). The overall native woody species density decreased by 79.7% in the invaded stand. However, non-metric multidimensional scaling (nMDS) and analysis of similarity (ANOSIM) indicated significant differences in native tree composition between invaded and uninvaded stands at all sites. In all three sites, all ecological indices had significantly lower values in invaded stands compared to uninvaded stands. The decrease in all ecological indices in invaded over uninvaded stands indicated that P. velutina invasion reduced the diversity of native woody plant species. Due to the incessant spread of P. velutina, it may become a long-term dominant species with an increasing impact on the native vegetation. Therefore, the findings of this study call for urgent management and appropriate control measures against the ongoing spread of this invader within the riparian zones of the Molopo River in North-West Province. [ABSTRACT FROM AUTHOR]

Anaemia continues to be a persistent concern among South African women of reproductive age (WRA), yet population specific information on its determinants remains sparse. We used baseline data from the Healthy Lives Trajectory Initiative a randomised trial (n = 480) to quantify factors associated with anaemia in Soweto, South Africa aged 18–25 years. We used multivariable logistic regression to describe associations with anaemia and used structural equation modelling to assess a theoretical model, which tested three categories socioeconomic status (household asset score, education level), nutritional factors (food security, leafy green vegetable and chicken and beef consumption, iron status and vitamin A status) and biodemographic factors (parity, age at start of menarche, HIV status, contraception use, anthropometry, and inflammation status). The multiple logistic regression showed that ID (OR: 2.62, 95% CI: 1.72, 3.98), iron deficiency erythropoiesis (IDE) (OR: 1.62, 95% CI: 1.07, 2.46), and elevated CRP (OR: 1.69, 95% CI: 1.04, 2.76), increased the odds of being anaemic. SEM analysis revealed Hb was directly and positively associated with adjusted ferritin (0.0031 per mg/dL; p≤0.001), and CRP (0.015 per mg/dL; p≤0.05), and directly and negatively associated with soluble transferrin receptor sTfR (-0.042 per mg/dL; p≤0.001). While contraception use had both a direct (0.34; p≤0.05) and indirect (0.11; p≤0.01) positive association with Hb. Additionally, chicken and beef consumption had a positive indirect association with Hb concentrations (0.15; p≤0.05) through adjusted ferritin. Iron deficiency was the main anaemia risk factor in this low resource setting. However, anaemia of inflammation is present. Therefore, we suggest that in our setting, WRA anaemia control programs that include interventions to reduce ID and inflammation should be tested. [ABSTRACT FROM AUTHOR]

Summary: Steinernema bakwenae n. sp. isolate SF857 has been isolated from a soil sample from the North West province of South Africa. The infective juveniles were isolated using Cobb's decanting and sieving method, hand-picked from the nematode population and inoculated directly onto wax moth larvae. Morphological and molecular characterisation provides evidence for placing the new species in the Khoisanae -clade, adding a fifth member to this all-African clade. The new species is characterised by the following morphological features: third-stage infective juveniles with a body length of 1106 (1013-1233) μ m, a distance from the anterior end to the excretory pore of 90 (81-103) μ m, and a tail length of 87 (76-103) μ m. The first-generation males can be recognised by a spicule length of 80 (66-89) μ m and by a gubernaculum length of 51 (44-56) μ m. The new species was confirmed by means of crossbreeding and characterised by means of sequences of the internal transcribed spacer (ITS), the partial 28S regions (D2-D3) of the ribosomal DNA and the mitochondrial cytochrome oxidase subunit (COI). Phylogenetic analyses show that S. innovationi and S. tophus are the closest relatives to S. bakwenae n. sp. in the Khoisanae -clade. [ABSTRACT FROM AUTHOR]

Orientation: The study attempted to establish the role played by different perceived corporate social responsibility (CSR) activities on the organisational commitment of employees. Research purpose: To investigate the nomological network of variables playing a role in the relationship between Perceived CSR and Affective Commitment. Motivation for the study: Understanding the contribution of perceived corporate social responsibility to the organisational commitment of employees could inform managerial attempts to facilitate positive employee attitudes. Research approach/design and methods: The current study utilised structural equation modelling to evaluate the hypothesised multivariate causal relationships in the proposed model. A convenience sample of 172 employees of a consumer goods company completed several questionnaires, including measures of Affective Commitment, Perceived CSR, Organisational Social Identity, Perceived Organisational Justice, Psychological Contract , as well as three cultural value orientations. Main Findings: The most significant finding of the study was the positive relationship between Perceived CSR and Affective Commitment. The results revealed that Perceived CSR has a positive impact on Perceived Organisational Justice and fulfilment of the Relational Psychological Contract. Both variables impacted on Organisational Social Identity , which was positively related to Affective Commitment. Practical/managerial implications: Organisations should ensure that employees are made aware of their CSR policies and activities through corporate communication. Organisations should also invest their resources in dealing with social problems that are regarded as important by employees and engage in fair human resource practices. Contribution/Value-add: Engagement in CSR activities could help retain and attract talented candidates and increase commitment and identification with the organisation. [ABSTRACT FROM AUTHOR]

This paper is a case study of a large-scale pillar collapse at the Everest Platinum Mine. A major contributing factor to the collapse was the presence of weak alteration layers in the pillars. These alteration layers are found in the Bushveld Complex in South Africa where the pyroxenite layers have been exposed to hydrothermal fluid flow, serpentinisation and layer-parallel shearing. The resulting clay-like material and the weak partings substantially reduce the pillar strength. From the literature survey, it is clear that weak seams in pillars reduce their strength and conventional pillar strength formulas overestimate the strength in these cases. As an alternative, a novel numerical modelling approach is proposed to study the pillar failure and to conduct a back analysis of the mine collapse. This consists of a limit equilibrium constitutive model implemented in a displacement discontinuity code. Two areas of the mine were simulated, namely part of the collapsed area and a second area, with larger pillars that is still stable. This allowed for a preliminary calibration of the limit equilibrium model. The model illustrated that a reduction in friction angle on the partings, owing to the presence of water in the collapse area, seems to be a factor that contributed to the collapse. Although encouraging results are obtained, calibration of the limit equilibrium model remains a challenge. Laboratory testing is required in future to determine the strengths of the weak partings and in particular, the difference in strength of the wet and dry alteration zone material. Highlights: Geological alterations substantially reduce the strength of hard rock pillars and the classical approach of using empirical pillar strength formulae for layout design does not work in these cases. A novel approach to simulate the pillar failure on a mine-wide scale is presented in this paper and this consists of a displacement discontinuity boundary element method using a limit equilibrium model to represent the pillar failure. The collapse of the Everest Platinum Mine in South Africa is described in the paper, it is used to test the proposed methodology, and it provides valuable data for researchers interested in case studies where pillar strength is reduced by weak layers. The proposed modelling methodology seems valuable to simulate the pillar failure and to design layouts for these types of ground conditions. Calibration of the limit equilibrium model remains a challenge, however. [ABSTRACT FROM AUTHOR]

White grubs are root feeding larvae of beetles (Coleoptera: Scarabaeidae) that are sporadic pests in agriculture and can lead to economic damage. The grubs feed on the roots of plants, while the adult beetle can bore into underground stems, as well as cause defoliation of plants. Sporadic incidence of larvae with symptoms of nematode infections were detected in wattle and sugarcane plantations in the KwaZulu-Natal province of South Africa. The larvae with infection symptoms were isolated, washed, and put on water traps to collect infective juveniles of possible nematode infections. Three species of entomopathogenic nematodes (EPNs) were isolated from the white grub larvae. These included Steinernema bertusi isolated from Maladera sp. 4., Oscheius myriophila from Maladera sp. 4 and Schizonchya affinis, and Steinernema fabii isolated from Maladera sp. 4., Pegylis sommeri, and S. affinis. Of these S. fabii was the most common species in the sample (87%). This is the first report of such a high diversity of locally occurring EPNs found naturally associated with white grub species in this region of South Africa. [ABSTRACT FROM AUTHOR]

This study aimed to analyse the diet of a pair of Bat Hawks Macheiramphus alcinus, based on regurgitated pellets, and the associated habitat-foraging groups that the prey species belonged to. A total of 908 regurgitated pellets were collected from underneath one nest tree in north-eastern South Africa, over a 24-month period. A total of 26 prey species were identified, of which 17 comprised bats and nine were birds. Seven prey species qualified as common in the diet (≥11 individuals): Pipistrellus hesperidus, Tadarida aegyptiaca, Scotophilus dinganii, Zosterops virens, Chaerephon pumilus, Afronycteris nana and Laephotis capensis. Most prey individuals were clutter-edge foragers: 41 individuals (67%) were birds, and 181 (42%) were bats. The Bat Hawks therefore foraged predominantly adjacent to vegetation. Future studies should examine the environmental factors that drive the abundance of insects in these habitats and the foraging techniques that birds and bats employ to prey upon them, to ultimately increase our understanding of the foraging framework that flying Bat Hawks exploit when hunting these flying animals. [ABSTRACT FROM AUTHOR]

Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a major phytosanitary pest of citrus in South Africa. Although several management tools exist, control options registered for use against the soil-dwelling life stages are limited. Both entomopathogenic nematodes (EPNs) and entomopathogenic fungi have been investigated previously, but they have not been studied in combination against T. leucotreta. Thus, this study investigated the interaction of an indigenous entomopathogenic fungus, Metarhizium pinghaense (previously anisopliae) FCM Ar 23 B3 with three indigenous EPNs: Steinernema yirgalemense 157-C, S. jeffreyense J194 and Heterorhabditis noenieputensis 158-C for increased late instar T. leucotreta larval mortality. Before interaction experiments, lethal concentration (LC) values for each of these microbial agents were determined through dose–response bioassays. Heterorhabditis noenieputensis recorded the highest LC50 amongst the nematodes (7.11 IJs/50 µl). Using the pre-determined LC70 value of M. pinghaense and the LC50 values for each of the nematode species, interaction experiments were conducted. Combinations of the nematodes either applied simultaneously with the fungus or at 24, 48, 72 or 96 h post-fungal application showed predominantly additive interactions. Synergy between the simultaneous application of S. yirgalemense and M. pinghaense was found, whilst the interaction between H. noenieputensis and M. pinghaense applied simultaneously and S. jeffreyense applied 24 h post-fungal application, recorded antagonistic interactions. The use of these agents in combination may therefore have the potential to increase control of T. leucotreta soil-dwelling life stages in citrus orchards across South Africa and should be further investigated. [ABSTRACT FROM AUTHOR]

Hypertension is a pressing global health issue, contributing to an increase in cardiovascular risk, as well as being the most common condition seen in South Africa. Lack of compliance with the prescribed therapy is one of the largest obstacles to achieving goal blood pressure in antihypertensive patients. The complexity of the drug therapy is a very important factor that is associated with noncompliance, as most patients require treatment with two or more drugs. The use of fixed-dose combination (FDC) therapy has various advantages, including simplification of the regimen, resulting in improved adherence. However, there are also disadvantages, e.g. the inability to provide individualised dose flexibility. This article provides an overview of available FDC therapy for hypertension in South Africa and the rational use thereof, by taking into account each combination’s complementary action, efficacy, safety and tolerability. [ABSTRACT FROM AUTHOR]

Soil properties are important drivers of species distribution and community structure in grassland. This study was undertaken to assess the influence of soil properties on woody plant distribution around six selected communally managed rangelands in the District. At each communal rangeland, a total of 25 plots of 20 × 20 m were surveyed to record the density, frequency, and composition of woody species. Soil samples were collected for thirteen soil variables. A Tukey HSD (Tukey's honestly significant difference) post hoc test was used to compare soil properties and canonical correspondence analysis (CCA) to relate the soil properties to the woody species distribution. The study recorded a total of 17 woody species in 9 families. Fabaceae was the most dominant family, and Senegalia mellifera was the most abundant and frequent encroaching species. Most of the species were native, whereas Prosopis velutina was the only invasive alien species recorded. Senegalia mellifera, P. velutina, and Terminalia sericea were considered the most encroaching in the study sites, with densities exceeding 2000 TE ha-1 (i.e., tree equivalent). CCA results exhibited the strong effect of soil variables on the distribution of woody plant species. CCA ordination analyses showed that K was the most influential soil variable on woody species distributions, followed by Mg, CEC, Na, pH, sand, clay and silt. In terms of woody distribution, the CCA diagram showed similarities between Disaneng, Logageng and Tshidilamolomo. This study provides baseline information on woody species diversity for future management of this ecosystem. [ABSTRACT FROM AUTHOR]

The potato leaf miner, Liriomyza huidobrensis (Diptera: Agromyzidae), is an important economic pest of potatoes across the world, causing substantial damage in most potato-growing areas. The use of local entomopathogens for the control of insect pests has been widely encouraged, coupled with several environmental advantages being contrasted to the effects achieved using chemical pesticides. The current study surveyed potato field soil to determine the presence of entomopathogenic nematode (EPN) and entomopathogenic fungi (EPF) species in the Sandveld region of the Western Cape province. Susceptibility of L. huidobrensis larvae and pupae to the isolated pathogens and other locally sourced isolates was evaluated. The results of the survey indicated the presence of an unknown free-living bacteria feeding insect-associated nematode species of the genus Acrobeloides, the EPN Heterorhabditis zealandica and two EPF species, Metarhizium robertsii and M. majus. All L. huidobrensis pupal (45–57%) and larval stages (52–72%) of the potato leaf miner showed susceptibility to the EPN species tested. Laboratory bioassays showed that the pupal and larval stages was the most susceptible (>72% infection) to Heterorhabditis baujardi. Liriomyza huidobrensis pupal stage showed high pathogenicity to isolates of M. robertsii (10C). Overall, all isolates of M. robertsii showed pupal pathogenicity ranging between 80% and 91%. Metarhizium robertsii outperformed Beauveria bassiana as a biocontrol agent against L. huidobrensis pupae in the laboratory. Results from this study indicate the potential of biologicals as future biocontrol agents in an integrated pest management system for potato production. [ABSTRACT FROM AUTHOR]

Plangia graminea, locally known as a katydid or “krompokkel”, is a minor pest of vineyards in the Western Cape province of South Africa. It feeds on leaves, and sporadically on the skin of grapevine berries. Under natural conditions, katydids are not of much agricultural importance, but pest outbreaks during favourable conditions can result in significant foliar damage. Observations indicate an increase in katydid abundance and damage intensity in recent years. Currently, no agrochemicals are registered for the control of this species, and its present natural enemies are unlikely to provide sufficient control without augmentation. In this study, 12 entomopathogenic nematode (EPN) species were evaluated against the nymphs of Plangia graminea in laboratory bioassays, and mortality by infection was investigated. Seven locally occurring nematode species achieved significant mortality, with H. zealandica, H. indica, S. jeffreyense and S. yirgalemense being found to perform the best (> 90% mortality). [ABSTRACT FROM AUTHOR]

• The expansion of bush encroachment threatens biodiversity of the riparian zone. • Knowing the density of different species could provide insight into how plant communities function in riparian zone. • There is evidence that Prosopis tends to encroach in the riparian areas in many parts of the arid and semi-arid areas in Southern Africa. • There is a need to promote the management of woody plant encroachment along the riparian zone in South Africa. Woody plant encroachment has become increasingly problematic in arid and semi-arid ecosystems with the potential to pose serious threats to natural vegetation composition and structure. Although several studies have documented the structure of woody plants in riparian zones, little attention has been given to quantifying woody plant encroachment along the Molopo River. This study was conducted to assess the composition and structural patterns of woody species in the encroached and benchmark sites situated along the riparian zone of the Molopo River near the Tshidilamolomo, Makgori and Loporung villages. Three 20 × 20 m plots were evenly laid out along five 200 m transects spaced approximately 30 m from each other to best represent woody vegetation variability at each site. Woody species were recorded and categorized into six height classes and tree densities were calculated. A total of ten woody plant species were identified, but not all species were a manifestation of woody encroachment. However, the invasive Prosopois velutina and the indigenous Senegalia mellifera , were dominant in the areas, with a tree cover above 40% and densities exceeding 2 000 Tree Equivalent per hectare (TE ha−1). These two woody species were considered as an indication of considerable woody encroachment in the study sites. Regarding woody density near the three villages, there were significant differences between the encroached and the benchmark sites. In both encroached and benchmark sites near the Makgori and Loporung villages, plant species exhibited an inverted J-shaped distribution which suggests the potential for long-term proliferation. In an encroached site near the Tshidilamolomo village, vegetation dominated by the invasive alien P. velutina revealed a bell-shaped pattern indicating an unstable population. Knowledge of the composition and structure of woody plant species near the three communally managed sites proves to be a relevant indicator of the ecological status of riparian ecosystems that could be used to identify high-risk areas, which may provide future opportunities for reducing and managing invasions. [ABSTRACT FROM AUTHOR]

Pseudococcus viburni (Hemiptera: Pseudococcidae), the obscure mealybug, is a serious polyphagous, cosmopolitan agricultural insect pest that affects deciduous fruit production in South Africa. The presence of the mealybug in orchards results in significant damage to crops, with economic implications. The potential use of two entomopathogenic fungi (EPF) and entomopathogenic nematodes (EPN), as biological control agents against P. viburni, was assessed under laboratory conditions, using screening bioassays. The EPF isolates, Metarhizium robertsii (6EIKEN) and M. pinghaense (5HEID), tested at a conidial concentration of 1 × 107 conidia/ml, proved to be effective against the adult stage female mealybugs, causing 96% ± 6% and 91% ± 13% mortality, respectively, 7 days post inoculation, when incubated at 25°C with humidity levels of > 95%. Heterorhabditis indica, applied at a concentration of 200 infective juveniles per insect, was found to be the most effective EPN against P. viburni, causing 79% mortality, 48 h post inoculation, while incubated at 25°C. Further bioassays showed a positive correlation between insect mortality and conidial concentration as well as exposure time. The study represents the first report on the pathogenicity of multiple local and commercial EPF isolates to control P. viburni and several local EPN isolates against P. viburni. [ABSTRACT FROM AUTHOR]

Trimen's false tiger moth, Agoma trimenii (Lepidoptera: Agaristidae), has developed pest status in vineyards in the Northern Cape and Groblersdal areas of South Africa, and an integrated pest management system is required. The objective of this study was to test the susceptibility of A. trimenii larvae to three commercial products (Delegate®WG, Steward®150 EC and three doses of DiPel® DF). Bioassay tests using all three products, and semi-field trials to test the potential of DiPel® DF against A. trimenii larvae, applied at different water volumes (50 g/1 000 L/ha and 50 g/1 430 L/ha) were performed. The residual activity of DiPel® DF, when applied at different water volumes, was investigated daily. Delegate® WG, Steward®150 EC and the recommended dose of DiPel® DF showed 100% larval mortality within seven days. Delegate® WG and the recommended dose of DiPel® DF proved to be the fastest acting products. The product label recommended dose of DiPel® DF (0.25 g/500 mL distilled water) proved the most effective dose (in comparison to halved and doubled dosages) and showed 100% mortality five days after application. Increasing the water volume per ha of a spray application of DiPel® DF for the same application area, showed no significant increase in larval mortality. A reduction in insecticidal activity for DiPel® DF applied at both water volumes was seen between leaves picked four days after spraying and leaves picked five days after spraying, and no mortality was observed after day 6. To help improve efficacy, attention should be given to increasing spray coverage and residual activity of DiPel® DF, as well as using all tested products within an integrated pest management system. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) of the genera Steinernema and Heterorhabditis have demonstrated great potential as useful bio-control agents in the management of certain important soil-inhabiting insect pests of agricultural crops. In a survey of nematodes associated with organic honeybush cultivation, soil samples were obtained from nine organic honeybush plots, which are located in the Bredasdorp area of the Western Cape province of South Africa. The EPNs were isolated from soil by baiting with larvae of Galleria mellonella (greater wax moth) and identified by the amplification of the internal transcribed spacer region using the primer set TW81 and AB28. EPNs were abundant in the honeybush orchards, accounting for about 50% of the sampled fields and five EPN species were identified including Heterorhabditis bacteriophora, Heterorhabditis safricana, Steinernema khoisanae,. Steinernema nguyeni, Oscheius sp. and an unknown EPN, therefore suggesting a substantial diversity of EPNs in the sampled fields. A 100% mortality of infected G. mellonella larvae was recorded within 48 h of exposure to the nematodes. However, although these EPNs have been previously reported in South Africa, it is the first time they are found in such diversity on a conservative tillage management system in organic honeybush cultivation. [ABSTRACT FROM AUTHOR]

Adequate intake of iodine is important during pregnancy because of its essential role in foetal growth and neurodevelopment. Data on iodine status of South African pregnant women are scarce, and the salt reduction policy implemented in 2016 may decrease iodine intake of South Africans. This cross‐sectional study assessed the iodine status of pregnant women residing in urban Johannesburg, South Africa. A total of 250 pregnant women were enrolled into the 'Nutrition during Pregnancy and Early Development' (NuPED) study and 312 pregnant women into the 'Assessment of dried blood spot thyroglobulin in pregnant women to redefine the range of median urinary iodine concentration that indicates adequate iodine intake, South Africa' (STRIPE‐SA) study and were included in this analysis. Urinary iodine concentration (UIC) was analysed in a spot urine sample. Thyroglobulin (Tg) was measured in serum, and thyroid‐stimulating hormone (TSH) and total thyroxine (tT4) were measured in dried blood spots. The median [interquartile range (IQR)] UIC of pregnant women was 144 (84–234) μg/L. Women in the first (n = 99), second (n = 262) and third (n = 174) trimester had a median UIC of 133 (81–316), 145 (84–236) and 156 (89–245) μg/L, respectively (p = 0.419). Median TSH, tT4 and Tg were 2.7 (2.3–3.2) mU/L, 202 (163–236) nmol/L and 9.2 (5.4–17.9) μg/L, respectively. Based on the median UIC, pregnant women residing in urban Johannesburg may be borderline iodine deficient. These findings highlight the need for ongoing monitoring of iodine status among vulnerable pregnant women, especially considering the recently introduced salt reduction policy in South Africa. [ABSTRACT FROM AUTHOR]

Nematodes play an important role in agricultural soil in terms of their pest status and their contribution to soil quality, where they may serve as a valuable indicator of soil health. The aim of the study was to assess changes occurring in nematode community structure, as affected by soil tillage applied to high N-input and irrigated pastures in South Africa. Such practices were investigated by means of analysing diversity and ecosystem function indices, as well as the faunal profile, to enable analysis of their effect on soil quality. The pre-treatment soil analyses showed a low overall mean nematode density. No clear and predictable pattern was present in the nematode community structure in relation to tillage. The lack of indicative information leading from the nematode community structure to the tillage disturbance types might be linked to the fact that such systems were able to recover from soil disturbance within the relatively short period of less than a year. [ABSTRACT FROM AUTHOR]

Pratylenchus bolivianus (Nematoda, Pratylenchidae) an important parasitic lesion nematode of ornamental and crop plants was found in association with rooibos (Aspalathus linearis) tea in the Cederberg region of South Africa. The population distribution and frequency of occurrence of P. bolivianus on the rooibos orchards were determined, and nematode characterization was done using a combination of traditional morphological characteristics, scanning electron microscopy (SEM), morphometrics and molecular marker by amplifying the D2-D3 expansion segment of the 28S ribosomal RNA gene. P. bolivianus occurred at 84.6% frequency in the sampled fields, with a mean population density that ranged between 10 and 770 lesion nematodes per 250 ml. The morphological features are similar to previous reports, with a slight variation in stylet length and ratio of 'a' due to intraspecific geographical variations. The en face view of the SEM shows pattern of the oral disc and first labial annule that is characteristic of P. bolivianus a pattern that falls under Group 2 classification. The phylogenetic relationships as inferred from Maximum Likelihood and Maximum Parsimony revealed a close relationship between the South African isolate of P. bolivianus and those published from other geographical locations. The study confirmed a morphological and genetic similarity between the amphimictic population of P. bolivianus from South Africa and those reported from Costa Rica. [ABSTRACT FROM AUTHOR]

The severe 2014–2020 drought in the southern Kalahari of South Africa resulted in extensive herbaceous cover and standing biomass losses. Droughts are a common phenomenon in this semi-arid savanna. The plants of this region have adapted to survive extreme rainfall variability and drought events. This adaptability and the inherent resilience (i.e. the ability to recover to its original state) of vegetation in the southern Kalahari enables it to recover quickly when conditions become more favourable. Droughts in the region are, however, predicted to increase in frequency and intensity due to global climate change. The associated increased aridity may also push many species beyond their tolerance threshold, leading to permanent shifts in vegetation dynamics. The aim of this study was to determine: (i) the growth vigour, cover abundance and productivity of herbaceous plant functional groups during the drought, (ii) the rate of post-drought recovery and (iii) the relative resilience and resistance of herbaceous plant functional groups. The drought affected all herbaceous plant functional groups as growth vigour, cover abundance and productivity were extremely low during the drought. All herbaceous growth started to recover post-drought but differed in their rate of response. Annual herbaceous species were found the be remarkably resilient to drought while perennial grasses were less resilient but far more resistant to the drought. Despite the resilience and rapid recovery of herbaceous growth, compositional changes post-drought were limited due to the degraded condition of the rangeland prior to the drought. The results emphasised the importance of sound management practices in the face of climate change. • Droughts reduces the growth vigour, cover abundance and productivity of herbaceous vegetation. • The rate of recovery post-drought of herbaceous vegetation differs among herbaceous plant functional groups. • Annual herbaceous species of the Kalahari are highly resilient while perennials are more resistant to drought. • Rangeland condition plays an important role in post-drought recovery. [ABSTRACT FROM AUTHOR]

Acute mental stressor–induced cardiac stress responses might contribute to excessive myocardial strain and resultant cardiovascular episode risk. We assessed ethnicity-specific acute cardiac stress (by measuring cardiac troponin T (cTnT) and N-terminal prohormone of brain natriuretic peptide) related to hemodynamic activity. The prospective Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study was conducted during 2007–2008 in South Africa. In the cross-sectional phase of the SABPA study, 388 black and white participants underwent a 1-minute acute mental stressor, during which blood pressure was continuously measured. Fasting blood samples for cardiac stress markers were obtained before and 10 minutes after stress (% change). Resting 10-lead electrocardiogram measured the R wave of the aVL lead (RaVL). Black participants exhibited greater cardiac stress responses (P < 0.001), diastolic blood pressure, total peripheral resistance, and stroke volume compared with white participants, who displayed decreases in cardiac stress and increases in cardiac output. Prestress and stressor cTnT cutpoints of 4.2 pg/mL predicted 24-hour, daytime, and nighttime diastolic hypertension in black participants (P < 0.001). These cTnT cutpoints were associated with an ethnicity-specific RaVL cutpoint of 0.28 mV (odds ratio = 3.49, 95% confidence interval: 2.18, 5.83; P = 0.021). Acute mental stress elicited an α-adrenergic activation pattern and cardiac stress hyperreactivity only in black participants. Mental stress might increase the black population's risk for ischemic episodes and heart disease. [ABSTRACT FROM AUTHOR]