1. Academic Wits Research Publications (Faculties submissions)
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Item Evidence for igneous differentiation in Sudbury Igneous Complex and impact-driven evolution of terrestrial planet proto-crusts(Nature Research, 2019-01) Latypov, Rais; Chistyakova, Sofya; Grieve, Richard; Huhma, HannuBolide impact is a ubiquitous geological process in the Solar System, which produced craters and basins filled with impact melt sheets on the terrestrial planets. However, it remains controversial whether these sheets were able to undergo large-scale igneous differentiation, or not. Here, we report on the discovery of large discrete bodies of melanorites that occur throughout almost the entire stratigraphy of the 1.85-billion-year-old Sudbury Igneous Complex (SIC) – the best exposed impact melt sheet on Earth – and use them to reaffirm that conspicuous norite-gabbro-granophyre stratigraphy of the SIC is produced by fractional crystallization of an originally homogeneous impact melt of granodioritic composition. This implies that more ancient and compositionally primitive Hadean impact melt sheets on the Earth and other terrestrial planets also underwent large-volume igneous differentiation. The near-surface differentiation of these giant impact melt sheets may therefore have contributed to the evolution and lithological diversity of the proto-crust on terrestrial planets.Item Assessing runs of Homozygosity: a comparison of SNP Array and whole genome sequence low coverage data(BMC, 2018-01) Ceballos, Francisco C.; Hazelhurst, Scott; Ramsay, MichèleBackground: Runs of Homozygosity (ROH) are genomic regions where identical haplotypes are inherited from each parent. Since their first detection due to technological advances in the late 1990s, ROHs have been shedding light on human population history and deciphering the genetic basis of monogenic and complex traits and diseases. ROH studies have predominantly exploited SNP array data, but are gradually moving to whole genome sequence (WGS) data as it becomes available. WGS data, covering more genetic variability, can add value to ROH studies, but require additional considerations during analysis. Results: Using SNP array and low coverage WGS data from 1885 individuals from 20 world populations, our aims were to compare ROH from the two datasets and to establish software conditions to get comparable results, thus providing guidelines for combining disparate datasets in joint ROH analyses. By allowing heterozygous SNPs per window, using the PLINK homozygosity function and non-parametric analysis, we were able to obtain non-significant differences in number ROH, mean ROH size and total sum of ROH between data sets using the different technologies for almost all populations. Conclusions: By allowing 3 heterozygous SNPs per ROH when dealing with WGS low coverage data, it is possible to establish meaningful comparisons between data using SNP array and WGS low coverage technologiesItem The effect of a ketogenic diet versus a high-carbohydrate, low-fat diet on sleep, cognition, thyroid function, and cardiovascular health independent of weight loss: study protocol for a randomized controlled trial(BMC, 2018-01) Iacovides, Stella; Meiring, Rebecca M.Background: Many physiological health benefits observed after following a ketogenic diet (KD) can be attributed to the associated weight loss. The KD has become more prominent as a popular health choice, not only in obese/ overweight individuals, but also in healthy adults. The study aims to determine the effects of a KD, independent of weight loss, on various aspects of physiological health including: sleep, thyroid function, cognition, and cardiometabolic health. The study will also aim to determine whether a change in basal metabolic rate may be associated with any changes observed. Methods: Twenty healthy men and women between 18 and 50 years of age will take part in this study. In a randomized controlled, cross-over design, participants will follow two isocaloric diets: a high-carbohydrate, low-fat diet (55% CHO, 20% fat, 25% protein) and a KD (15% CHO, 60% fat, 25% protein). Each dietary intervention will last for a minimum of 3 weeks, with a 1-week washout period in between. Before and after each diet, participants will be assessed for sleep quality, cognitive function, thyroid function, and basal metabolic rate. A blood sample will also be taken for the measurement of cardio-metabolic and immune markers. Discussion: The present study will help in understanding the potential effects of a KD on aspects of physiological health in healthy adults, without the confounding factor of weight loss. The study aims to fill a significant void in the academic literature with regards to the benefits and/or risks of a KD in a healthy population, but will also explore whether diet-related metabolic changes may be responsible for the changes observed in physiological health.Item The importance of morphological identification of African anopheline mosquitoes (Diptera: Culicidae) for malaria control programmes(BMC, 2018-01) Erlank, Erica; Koekemoer, Lizette L.; Coetzee, MaureenBackground: The correct identification of disease vectors is the first step towards implementing an effective control programme. Traditionally, for malaria control, this was based on the morphological differences observed in the adults and larvae between different mosquito species. However, the discovery of species complexes meant that genetic tools were needed to separate the sibling species and today there are standard molecular techniques that are used to identify the two major malaria vector groups of mosquitoes. On the assumption that species-diagnostic DNA polymerase chain reaction (PCR) assays are highly species-specific, experiments were conducted to investigate what would happen if non-vector species were randomly included in the molecular assays. Methods: Morphological keys for the Afrotropical Anophelinae were used to provide the a priori identifications. All mosquito specimens were then subjected to the standard PCR assays for members of the Anopheles gambiae complex and Anopheles funestus group. Results: One hundred and fifty mosquitoes belonging to 11 morphological species were processed. Three species (Anopheles pretoriensis, Anopheles rufipes and Anopheles rhodesiensis) amplified members of the An. funestus group and four species (An. pretoriensis, An. rufipes, Anopheles listeri and Anopheles squamosus) amplified members of the An. gambiae complex. Conclusions: Morphological identification of mosquitoes prior to PCR assays not only saves time and money in the laboratory, but also ensures that data received by malaria vector control programmes are useful for targeting the major vectors.Item Feeding children with autism in South Africa: the teachers’ perspectives(AOSIS Publishing, 2024-02) Adams, Skye N.; Matsimela, NthabisengBackground: Over 80% of children diagnosed with autism spectrum disorders (autism) exhibit disruptive behaviours during mealtimes, highlighting the need for personalised care. In South Africa, teachers often take on the responsibility of feeding due to resource constraints and the time children spend at school. Moreover, children with autism have unique and individualised feeding requirements, which many teachers may not have the necessary training or skills to address adequately. Objectives: To explore the ways in which teachers of autistic children manage feeding difficulties in the classroom. Method: A qualitative research design was employed using semi-structured interviews. Eight teachers were interviewed on feeding autistic children between the ages of 3 years - 9 years in Johannesburg, South Africa. Data were transcribed and analysed using thematic analysis. Results: The findings revealed that teachers encountered distinct challenges when it came to feeding autistic children in the classroom, particularly concerning the management of associated feeding difficulties. Teachers employed several strategies to encourage eating in the classroom setting including: (1) bolus modification, (2) behaviour modelling, (3) positive reinforcement and (4) offering choices and alternatives. Conclusion: The study concludes the need for specialised support and training for teachers to address the individualised feeding needs of children with autism. Implementing targeted interventions and providing resources for teachers could enhance their abilities to effectively support children with autism during mealtimes and promote a more inclusive classroom environment. Contribution: This study highlighted the importance of including the teacher in the multidisciplinary team when managing the feeding challenges in children with autism.Item Exploring quality of life post sudden onset hearing loss: a convergent parallel approach(AOSIS Publishing, 2024-02) Ntlhakana, Liepollo; Hamid, SabeehahBackground: Sudden onset hearing loss (SOHL) is rare and presents differently to individuals; hence, it is complex to diagnose. The impact on the quality of life (QoL) varies for individuals and their support structure. However, the exploration of research designs is warranted. Objectives: This study explored the lived experiences of adults post-SOHL diagnosis and the impact on the QoL. Facilitators of emotional and social aspects of counselling provided by audiologists post-SOHL diagnosis were established. Method: This was a convergent parallel research study. Data were collected from the two primary participants and three secondary participants, face-to-face and telephonically. The Hearing Handicap Inventory for Adults (HHIA) screening tool and the semi-structured interviews were used for data collection. The data sets were analysed independently, viz. descriptive analysis and thematic analysis, to confirm the impact on the QoL post-SOHL diagnosis. Results: The HHIA scores obtained were 84% and 50% for P1 and P2, respectively. Key themes that emerged from the interviews revealed that communication difficulties mostly impacted the QoL, which in turn influenced their mental and social well-being. Aural rehabilitation was perceived as ineffective support, thus the inability to reduce the impact on the QoL post-SOHL diagnosis. Conclusion: The integrated findings indicated the impact on the QoL post-SOHL diagnosis. Convergent parallel methods should be considered by researchers to understand rare auditory pathologies and their impact on the QoL. Contribution: Person-centred care (PCC) and family-centred care (FCC) are facilitators of counselling that audiologists can employ as QoL management strategies post-SOHL diagnosis.Item The assessment and aetiology of drug-induced ischaemic priapism(Springer Nature, 2024-12) Moodley, Divyen; Badenhorst, Anja; Choonara, Yahya; Adam, AhmedIschaemic priapism is a urological emergency characterised by a prolonged, painful erection unrelated to sexual stimulation. While several aetiological factors contribute to this condition, the pharmacological causes have gained significant attention in recent years. This narrative review aims to comprehensively assess ischaemic priapism, specifically focusing on its pharmacological aetiology. We propose an approach and assessment strategy to the numerous factors associated with pharmacologically induced ischaemic priapism. By enhancing our understanding of the harmacological causes of this condition, healthcare professionals can improve patient management and reduce the long-term complications associated with ischaemic priapism.Item E-learning assessment framework for the public service sector(Public Service Sector Education and Training Authority (PSETA), 2021) Centre for Researching Education & Labour (REAL); University of the Witwatersrand, JohannesburgThe purpose of this research project was to develop an understanding of the change drivers and difficulties linked to implementing e-learning in the South African Public Service Sector in line with policy imperatives and global trends. The project aimed to investigate specific challenges and contextual variables that need to be addressed to strengthen skills development within the public sector. It also aimed to explore how to enhance ways in which the public sector utilises e-learning to upskill and re-skill its workforce. The research was undertaken over a 12-month period, from September 2020 to September 2021, and involved five main phases. Phase One comprised the inception and orientation of the project. The second phase involved a literature review on e-learning including an analysis of relevant public sector documents, reports, and policies on e-learning practices within the public and private sector. This contextual profile describes e-learning practices in the sector and enabled us to structure the public e-learning system as an activity system. The third phase consisted of the development of mediating tools including a comprehensive evaluation tool to offer a potential way forward to enhance strategic planning implementation for e-learning. This will assist with addressing the challenges faced by the public sector in terms of training and the processes of change involved in transitioning the conceptualisation of e-learning to contextualised capacity building. The e-learning criteria framework provides basic guidelines for designing an optimum e-learning experience in the public sector. The elearning review tool (Appendix A) supports and complements the criteria as a tool for analysis of the e-learning programme. The e-learning criteria and tool were sent to ten e-learning experts in the same field of research for comments on further development and improvement. Phase Four consisted of data analysis. Insights from stakeholder engagement and framework development processes were assessed and key emergent themes to inform the e-learning needs of the public sector were identified. In the final phase the findings were reviewed and recommendations proposed and the final report presented here is based on reviewer feedback.Item The shift to outcomes based frameworks: key problems from a critical perspective(The Federal Institute for Adult Education (bifeb), 2011) Michael, Young; Allais, Stephanie MatselengThis paper takes a step back from the discussions and debates about qualifications frameworks per se, to think more broadly about the role of „qualifications“ in educational reform. The aims of the paper are to locate the reform of qualifications in its broader social and institutional context, to propose a way of conceptualizing the change from qualification systems as they have emerged historically to qualifications frameworks andoutcomes-based qualifications and to explore the tensions involved in the different goals that the introduction of a (National) Qualifications Framework – (N)QF will achieve. We argue that what is at stake in current reforms is the role of educational institutions in the education and training of the next generation, the balance between institution-based education and informal (in some cases work-based) learning, and the ways in which trust in qualifications is established and maintained. Our two-model analysis explores the balance between an emphasis on institutions and outcomes. This paper was written to provoke debate, and help all involved in researching qualifications frameworks to think more clearly about the issues.Item The Miocene primate Pliobates is a pliopithecoid(Nature Research, 2024-04) Amélie Beaudet; Zanolli, Clément; Urciuoli, Alessandro; Almécija, Sergio; Fortuny, Josep; Robles, Josep M.; Bouchet, Florian; Moyà-Solà, Salvador; Alba, David M.The systematic status of the small-bodied catarrhine primate Pliobates cataloniae, from the Miocene (11.6 Ma) of Spain, is controversial because it displays a mosaic of primitive and derived features compared with extant hominoids (apes and humans). Cladistic analyses have recovered Pliobates as either a stem hominoid or as a pliopithecoid stem catarrhine (i.e., preceding the cercopithecoid–hominoid divergence). Here, we describe additional dental remains of P. cataloniae from another locality that display unambiguous synapomorphies of crouzeliid pliopithecoids. Our cladistic analyses support a close phylogenetic link with poorly-known small crouzeliids from Europe based on (cranio)dental characters but recover pliopithecoids as stem hominoids when postcranial characters are included. We conclude that Pliobates is a derived stem catarrhine that shows postcranial convergences with modern apes in the elbow and wrist joints—thus clarifying pliopithecoid evolution and illustrating the plausibility of independent acquisition of postcranial similarities between hylobatids and hominids.