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The demographic-specific prey preferences of lions and cheetahs, and potential impacts on prey populations
Get PDFUnderstanding prey selection offers predictive insights into predator-prey interactions, which can be extended to explore the impacts of predators on prey populations. Prey availability and vulnerability vary across species, demographic classes, body sizes, and seasons. Traditional prey selection models for large carnivores, based on estimates of prey body size, assume uniform vulnerability across prey demographic classes and seasons, failing to account for these variations. This study aims to contrast seasonal shifts in demographic-specific prey preferences between lions and cheetahs and examine the potential impact of their demographic-specific predation patterns on a range of prey species across a body size spectrum. It was predicted that cheetahs would shift their selection from adults and juveniles of smaller prey species in the dry season to neonates and juveniles of both smaller and larger prey species in the wet season, while lions would select adults irrespective of the season. Additionally, predation focusing on adults would have a greater impact on prey populations compared to predation focusing on non-adults. Furthermore, it was predicted that prey populations experiencing demographic-specific selection from both lions and cheetahs would be impacted more than species selected by only one predator. Degrees of preference (DOP) were estimated based on prey availability (camera traps) and prey use (GPS clusters) for lion and cheetah populations in Lapalala Wilderness Reserve. Generalized Additive Models for Location, Scale, and Shape (GAMLSS) were used to determine seasonal shifts in demographic-specific prey preferences. The seasonal-demographic specific predation patterns of lion and cheetah, along with prey vital rates extracted from the literature, were then used to model potential predation impacts on prey populations using both Leslie-Usher and Lefkovitch matrix models. Lions preferred larger adult prey such as blue wildebeest, eland, and buffalo, while cheetahs preferred smaller prey, particularly juveniles of small to intermediate-sized species like impala, kudu, blue wildebeest, and zebra. Both predators showed seasonal shifts in demographic-specific prey preferences, with lions selecting adult buffalo during the dry season and juvenile buffalo in the wet season, and cheetahs selecting juveniles in the dry season and neonates and juveniles during the wet season. Lions and cheetahs exerted the highest degree of top-down limitations on their preferred prey. Predation on adult prey had a greater effect on prey population growth rates than predation on non-adults, especially in the dry season. Intermediate-sized prey species experienced the highest predation pressures, while larger prey species were more affected than smaller ones, contrary to the size-nested predation hypothesis. My study represents a first effort in the southern hemisphere to model the demographic impacts of multiple predators on diverse prey species, incorporating seasonal and demographic-specific prey preferences. The findings emphasise the importance of incorporating prey demographics and seasonality in predator-prey studies as these refined studies have implications for the management and conservation of both predator and prey populations.Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 202
The Camdeboo-Mountain Zebra mega-reserve as an opportunity to protect viable populations of medium- to large-sized mammals
Get PDFConservation planning has focused extensively on representation of species in protected areas (PAs), rather than achieving the persistence of these species in PAs. Consequently, most PAs do not support viable populations of many species represented within them, particularly large mammals, resulting in extinction debt risks. The challenge is therefore to identify opportunities to achieve viable populations and to develop and implement conservation plans to achieve this, e.g., expand and connect existing PAs. A recent meta-analysis provides a minimum viable population (MVP) estimate of 5 000 individuals for mammals. This value was used as the target for modelling conservation opportunities for the South African endemic Cape mountain zebra (Equus zebra zebra), blesbok (Damaliscus pygargus phillipsi), black wildebeest (Connochaetes gnou) and co-existing medium- and large-sized mammal species. This study focused on the region between the Camdeboo and Mountain Zebra national parks (ca. 736 000 ha). Within the envisaged Camdeboo-Mountain Zebra (C-MZ) mega-reserve, a spreadsheet model was used to estimate potential herbivore population sizes, spatial requirement data were used to estimate potential omnivore and insectivore population sizes, and herbivore densities were used to estimate potential large carnivore population sizes. I show that 12 (the three endemic grazers and nine co-existing species) of the 28 modelled medium- and large-sized mammal species will potentially exceed 5 000 individuals, the MVP target, within the envisaged mega-reserve. The remaining 16 species show potential to reach substantial population sizes, however, will likely require ongoing metapopulation management. Using a conservation planning approach, I identify priority areas for the conservation of suitable habitat for Cape mountain zebra, blesbok, and black wildebeest within the envisaged mega-reserve, thus indirectly identifying priority areas for the conservation of these endemic species. I show that the potential incorporation of these priority areas within the envisaged mega-reserve will contribute considerably to the conservation of all focal species. In addition, the potential incorporation of these priority areas will contribute to PA expansion and significantly improve connectivity between existing PAs within the envisaged C-MZ mega-reserve. The importance of adequately-sized PAs to support viable populations of focal species is thus evident, and will ensure their long-term survival and ability to persist by allowing population and evolutionary scale processes.Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 202
IL-4/ IL-13 directed microglial activation and differentiation in response to LPS-induced neuroinflammation
Get PDFMicroglia activation is a common hallmark of neuroinflammation that occurs during pathogen invasion or lipopolysaccharide (LPS)-induced inflammation. A neuroinflammatory response is elicited by the release of proinflammatory cytokines which stimulates microglia in an autocrine manner to be polarized into classically activated, pro-inflammatory M1 cells. Prolonged exposure to the inflammatory response can have disastrous effects on the central nervous system (CNS). However, microglia can alternatively be polarized into the activated M2 anti-inflammatory phenotype, but the exact molecular mechanism mediating this phenotypic switch remains poorly understood. Studies have shown that interleukin (IL)-4 can induce the M2 phenotype and activate the signal transducer and activator of the transcription 6 (STAT6) signalling pathway that in turn provokes a beneficial Th2 immune response. Since IL-4 and IL-13 share a common IL-4 receptor alpha (IL-4Rα) chain, it is possible that alternative microglia differentiation and its anti-inflammatory action also involve IL-13. This study aimed to investigate how IL-13 and STAT6 signalling orchestrates the microglial response and differentiation associated with LPS-induced inflammation. Furthermore, the molecular mechanisms that relieve LPS-induced neuroinflammation and neural protection through IL-13-enhanced BDNF signalling were also investigated. C8-B4 microglial cells were induced with LPS to exhibit an M1 pro-inflammatory phenotype or stimulated with IL-4 and/or IL-13 to exhibit an M2 anti-inflammatory microglial phenotype. The cell viability following LPS, IL-4, and/ or IL-13 exposure was determined. The LPS-induced neuroinflammatory response and the anti-inflammatory response induced by IL-4 and IL-13 which promotes STAT-6 signalling were determined by measuring TNFα, IL-1β, and BDNF protein concentrations using ELISA assays. The polarising effects of LPS and IL-4/IL-13 cytokines were also examined via changes in the expression of Iba-1, CD206, CD86, and STAT-6 determined by immunofluorescence analysis. These changes were further investigated by quantifying the mRNA transcripts of TNFα, IL-1 β, Arg-1, CD206, IL-4R, and STAT-6 and BDNF using qRT-PCR.Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 202
Relationship Management in All-Boys’ Fee-paying Public Schools in the Eastern Cape, South Africa : Experiences and Perspectives of LGBTQ Alumni
Get PDFThis study explores the perspectives and experiences of LGBTQ alumni of all-boys’ schools in the Eastern Cape. The context of increased competition between schools in the education sector and the importance of inclusion within the sector necessitated a study to investigate the extent to which relationship management is conducted with an orientation towards LGBTQ inclusion in all-boys’ schools in the Eastern Cape. Student protests in South Africa over the past 10 years have expanded concerns about student belonging beyond the widely studied lenses of race and class. A growing body of literature and wider discourse emphasises student belonging as a challenge in the South African education sector. Marginalised students continue to experience educational spaces negatively. LGBTQ student experiences in the South Africa are characterised by violence and ostracisation, thus warranting further investigation and inquiry. The study locates itself in the intersections between gender and sexual diversity and economic citizenship in the broader discourse of school inclusivity. A qualitative research approach was employed, making use of semi-structured, in-depth individual interviews. The sample was derived from alumni of all-boys’ schools in the Eastern Cape through snowball sampling. Ten LGBTQ-identifying alumni of boys’ schools in the Eastern Cape were interviewed. The findings reveal the need to question the extent to which LGBTQ alumni can enjoy the fullness of the value proposition of all-boys’ schools, and what can be done to ensure LGBTQ belonging. The findings of this study concur with existing literature about LGBTQ experiences. Participants defined their school experiences as exclusionary and characterised by fear of failing to assert themselves in a hypermasculine school environment. LGBTQ alumni of all-boys’ schools in the Eastern Cape view relationship management as under-utilised as a tool to facilitate LGBTQ belonging. Instead, relationship management is used to affirm those who fit the mould of the quintessential ‘old boy’ network, by defining the masculine behaviours that learners in all-boys’ schools are compelled to aspire towards. v ABSTRACT The findings illustrate that the culture of silence around non-confirming sexuality is sustained in the post-schooling relationship management life-cycle and results in the absence of the LGBTQ customer voice in the drafting of school strategy and policy. LGBTQ alumni who speak out about controversial issues often face admonition from their former teachers and peers. LGBTQ alumni criticise the relationship management of their former schools for the over-emphasis on fundraising and the complete absence of discussions on diversity. LGBTQ alumni are therefore marginalised in the process of value co-creation, as LGBTQ alumni feel they will never be viewed as legitimate collaborators by their former schools. The suggested recommendations emerging from this study include the need to codify school policies that speak specifically to LGBTQ marginalisation. Furthermore, schools must endeavour to make specific enquiries into LGBTQ student experiences and include LGBTQ concerns in wider school discourse.Thesis (Ma) -- Faculty of Business and Economic Sciences, 202
A critical analysis of the music educator’s role in managing adolescent music performance anxiety
Get PDFMusic performance anxiety (MPA hereafter) has been widely reported in adolescent musicians (Braden, Osborne & Wilson, 2015; Dempsey & Comeau, 2019; Fehm & Schmidt, 2006; Kenny & Osborne, 2006; Osborne & Kenny, 2008; Papageorgi, 2021; 2022; Patston & Osborne, 2016; Rae & McCambridge, 2004; Thomas & Nettelbeck, 2014). Even though adolescent musicians experience MPA, research indicates that music educators do not necessarily discuss MPA with them (Fehm & Schmidt, 2006; Gill, Osborne & McPherson, 2022; MacAfee & Comeau, 2022; Ryan, Boucher & Ryan, 2021). Music educators have also indicated that they are rarely taught about MPA in tertiary courses (Moura & Serra, 2021; Norton, 2016). However, adolescents have expressed wanting more assistance managing MPA from their music educators (Fehm & Schmidt, 2006). Since adolescents expressed the need for assistance from music educators in managing MPA, my interest grew in researching the music educator’s role as depicted in literature, hence the motivation for this research study. Therefore, the purpose of this study was to critically analyse the role of music educators in managing MPA in adolescent musicians. The role of music educators in managing adolescents’ MPA was addressed through the following primary research question: How does literature reflect the role of the music educator in managing adolescent MPA? In addition, the following sub-question was developed: Which coping strategies and treatments are mentioned in literature to assist music educators in managing adolescent MPA? An integrative literature review was chosen as the study’s methodology to critique and synthesise literature on the topic. Critical analysis and synthesis were used to identify aspects of adolescent MPA, music educators and MPA management that have been omitted or partially addressed in past research to form a new perspective. The critical analysis yielded areas in which new knowledge is needed. These results highlight the need for school music curriculums to contain guidelines regarding MPA and that music educators should be equipped with relevant knowledge to manage MPA effectively in adolescents. A research agenda was created to address the identified shortcomings. The research agenda demonstrates that information about MPA could be included in the school music curriculum in South Africa.Thesis (MMus) -- Faculty of Humanities, School of Visual and Performing Arts, 202
Communicating positive representations of wheelchair users’ disability identities through illustration and participatory design
Get PDFThe study highlights the misrepresentation of people with disabilities in the media, and how it can lead to social exclusion of people with disabilities and misunderstanding of the disability identity. The research question involves disability representation, wheelchair-disabled identity, illustration and participatory design. The study focuses specifically on wheelchair disability and uses a participatory design approach, which allows for wheelchair users collectively to be part of the research. The three different models of disability, namely the medical model, the social model and the cultural model. The South African definition of disability is explored, and images and photographic examples of past representations of disability are examined to identify stereotypes, such as the freak, the medicalised disabled body and the pitiful victim. Positive illustrations, paintings and posters of people living with disabilities are analysed, focusing on physical disability and representation, which reveals that illustration can instil good staring habits from non-disabled viewers, to create a more inclusive society. A qualitative research approach is employed to gain a better understanding of a specific phenomenon. The specific phenomenon was the representation of wheelchair disability identities, and to untangle this, three research approaches were used, namely autoethnography, case studies and participatory design. A total of 10 wheelchair-disabled persons, from Cheshire Home Summerstrand in Gqeberha participated in the study. It was found that by involving participants in the practical development process, more positive illustrations of disability representation can be produced, allowing for clearer communication of the disability identity. The responses to the interview questions confirmed that people with disabilities believe that non-disabled people have misconceptions about the disability identity. The research thus aims to challenge these misconceptions and motivate more positive interpretations and understanding of the disability identity through visual communication.Thesis (MVA) -- Faculty of Humanities, School of Visual and Performing Arts, 202
The influence of board member competency on the organisational performance of private sector companies in Eastern Cape, South Africa
Get PDFThis study investigates the significant influence that board member competency has on the organisational success of South African companies. Employing a quantitative analysis, the study concentrates on key areas of board competence, such as finance, policy interpretation, human resource management, and educational backgrounds. The results show that board members with expertise improve the effectiveness of governance, the calibre of financial reporting, and the choice of strategic investments. Furthermore, there is a correlation between enhanced decision-making procedures to better organisational results and the board members' proficiency in personnel management. The study also emphasises the critical role that board members have in interpreting policies, stressing their impact on the strategic direction and operational efficacy of businesses. Diverse perspectives and critical thinking are fostered by a board membership with a range of educational backgrounds, which has a favourable effect on return on investment and corporate governance. Overall, this study highlights how crucial a diverse board of directors is to advance organisational success and accomplish strategic goals in the ever-changing environment of South African private sector businesses.Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 202
Synthesis of two tartaric acid-derived host compounds and their behaviour in mixed pyridines and mixed heterocyclic guest compounds
Get PDFThe host compounds (4R,5R)-bis(diphenylhydroxymethyl)-2-spiro-1’-cyclopentane-1,3-dioxolane (TADDOL5) and (4R,5R)-bis(diphenylhydroxymethyl)-2-spiro-1’-cyclohexane-1,3-dioxolane (TADDOL6) were successfully synthesized after initially reacting diethyl tartrate with either 1,1-dimethoxycyclopentane or 1,1-dimethoxycyclohexane to afford the intermediates diethyl 2-spiro-1’-cyclopentane-1,3-dioxolan-4,5-dicarboxylate or diethyl 2-spiro-1’-cyclohexane-1,3-dioxolan-4,5-dicarboxylate. These were then each subjected to a Grignard addition reaction with PhMgBr to furnish TADDOL5 and TADDOL6 in reasonably high yields (77 and 80%, respectively). Computational calculations were performed on TADDOL5 and TADDOL6 using the software programs Avogadro and ORCA. The optimised geometries of these host molecules were obtained using the MMFF94 force field in Avogadro, while ORCA was used to perform the computational modelling at the BLYP level using the 6-31G*, 6-31G**, 6-311G* and 6-311G** basis sets and, also, the B3LYP functional (with the same basis sets) to obtain the three lowest energy conformers. The final geometries of each conformer for both TADDOL5 and TADDOL6 at the B3LYP 6-311G* level were overlaid with the molecules obtained from their crystal structures. Significantly different geometries were thus noted for the calculated conformers compared with the guest-free TADDOL5 and TADDOL6 structures obtained from the SCXRD experiments. When TADDOL5 was crystallized independently from each of PYR, 2MP, 3MP and 4MP, 1:1 H:G inclusion complexes formed in each instance. This host compound was then investigated for its host separation ability of mixed pyridines through supramolecular chemistry protocols. These mixed guest experiments revealed that TADDOL5 possessed a notable selectivity towards 3MP and PYR (in the absence of 3MP) followed by 4MP and 2MP, and it was shown that TADDOL5 is a suitable host candidate for the separation of many of the mixed pyridines employed here. The results of the SCXRD analyses indicated that the only significant (host)π···π(guest) stacking interaction present was between TADDOL5 and the most favoured guest species PYR and 3MP. Furthermore, significantly shorter (host)O‒H···N(guest) iv hydrogen bonds were also observed in the complexes formed between this host compound and 3MP and PYR compared with these bonds involving disfavoured 4MP and 2MP. Hirshfeld surface considerations provided an explanation for the affinity of TADDOL5 for PYR (but not 3MP), while thermal analyses successfully explained this affinity: the 3MP-containing complex with the most preferred guest species was the most thermally stable one, followed by TADDOL5·PYR, as obtained through a consideration of the Ton values (the temperature at which the guest release event initiated) of the four complexes. As with TADDOL5, TADDOL6 formed 1:1 H:G inclusion compounds with each of the four pyridines. TADDOL6 was, furthermore, also assessed for its separation ability for mixed pyridines, and these guest competition experiments showed that the selectivity of TADDOL6 was for PYR and 3MP (in the absence of PYR), followed by 4MP and 2MP. (Interestingly, TADDOL5 preferred 3MP and then PYR, while both host compounds disfavoured 4MP and 2MP.) The results obtained in this work indicated that TADDOL6 may also serve as an efficient host candidate for the separation of many of these pyridyl solutions. SCXRD experiments demonstrated that the only significant (host)π···π(guest) stacking interactions were those between TADDOL6 and preferred PYR and 3MP, as was the case for TADDOL5. These experiments also revealed that the strongest (host)O‒H···N(guest) hydrogen bonds were between TADDOL6 and these favoured guest species. A consideration of Hirshfeld surfaces and quantification of the (guest)N···H(host) intermolecular interactions correlated with the host selectivity order, as did thermal analyses, where the Ton values confirmed that the thermal stabilities of these complexes decreased in the guest order PYR > 3MP > 4MP > 2MP. The behaviour of TADDOL5 was further investigated in guest compounds DIO, PYR, PIP and MOR. Each guest solvent formed 1:1 H:G inclusion complexes with the host species, with the exception of DIO, which formed a 2:1 H:G complex. Mixed guest experiments revealed a clear preference for PIP and MOR, while PYR and DIO were less favoured. The host selectivity was demonstrated to be in the order PIP > MOR > PYR > DIO. SCXRD experiments showed that TADDOL5 formed a much shorter (and more linear) (host)O‒H···N(guest) hydrogen bond with the most favoured guest, PIP, compared to those involving MOR and PYR. A (host)O‒H···O(guest) hydrogen bond v was also observed in the DIO-containing inclusion complex. A consideration of the Hirshfeld surface interactions was not useful in explaining the host selectivity order for these heterocyclic guests, but thermal analyses confirmed that the most stable complex was the one with favoured PIP, followed by those with PYR, MOR and DIO. TADDOL6, on the other hand, formed 1:1 H:G inclusion compounds with all four of the heterocyclic guest solvents. Experiments in mixed guests showed that the selectivity of this host compound for these guests was in the order PYR > PIP > MOR > DIO, which differed from the TADDOL5 (which favoured PIP and then MOR). Interestingly, the strongest classical hydrogen bond was not formed with the most favoured guest PYR, but with PIP instead (this bond with TADDOL5 was also strongest with PIP, but PIP was favoured in that work). Hirshfeld surface investigations again were not useful in understanding the host selectivity behaviour. However, thermal analyses agreed with the observations made in the mixed guest experiments: the most stable complex was with PYR (favoured) and the least stable one was with DIO (least preferred).Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 202
Evaluating factors influencing quality of service delivery in the Nelson Mandela Bay Municipality
Get PDFThe provision of quality service continues to be a challenge in South Africa. This research was triggered by the quality of service delivery, which indicated a downward trend in the Nelson Mandela Bay Municipality during the past five years. Notably, deficiencies in the quality of service delivery are a prevalent problem for municipalities, including the Nelson Mandela Bay Municipality. Insufficient strategic leadership skills in management lead to a lack of satisfaction, motivation and a loss of loyalty among employees, which leads to poor quality of services delivered to the community. In order to understand the relationship between employee loyalty, employee satisfaction, leadership styles, and quality of service delivery, this study aimed to evaluate the factors influencing the quality of service delivery in the Nelson Mandela Bay Municipality with the intention to enhance these from the employee’s perspective. This study followed a quantitative approach with stratified random sampling. Online surveys were used to collect data from sampled Nelson Mandela Bay Municipality employees. The sample size was 110 respondents, and a 66.09% response rate was achieved. Data analysis techniques used in the study included exploratory factor analysis (EFA) to extract statistically significant factors. Multiple regression analysis was employed to evaluate the predictive power of independent variables (Employee Empowerment, Loyalty of Employees, Employee Satisfaction, Transformational Leadership) over the dependent variable (Quality of Service). The Pearson Product Moment Correlation analysis was used to determine the relationship between the independent and dependent variables. The findings revealed that Employee Empowerment did not influence the quality of service in the Nelson Mandela Bay Municipality. The study's findings reveal that at 95% confidence level and alpha = 0.05, Loyalty of Employees, Employee Satisfaction, and Transformational Leadership significantly positively influence the Quality of Service. The study recommends that Nelson Mandela Bay Municipality management must embark on initiatives like life-work balance, organisational commitment, innovation behaviour, and benchmarking to improve the quality of service delivery. The study has contributed to the existing body of knowledge on quality of service by introducing Loyalty of Employees, Employee Satisfaction, and Transformational Leadership as factors significantly positively influencing the quality of service delivery compared to the renowned SERVQUAL dimensions (Empathy, Responsiveness, Assurance, Reliability, and Tangibility). The study's finding indicatedThesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 202
A critical analysis of the interpretation of a permanent establishment created where a subsidiary acts as a dependent agent for its parent company
Get PDFIn recent years, the need arose to amend the DAPE provisions in the OECD MTC due to the ever-evolving nature of the tax avoidance strategies employed globally. This research study analysed the amendments that were made to the DAPE provisions of Article 5(5) of the 2014 OECD MTC, including the related OECD Commentary thereto and the extent to which the Commentary can be relied on. The relevance of the amended DAPE provisions were discussed by analysing the PE definition in SA’s domestic tax law, SA’s position on the MLI and consequently its position on Article 12 of the MLI which incorporates the amended DAPE provisions into existing DTAs. The scope of the research was limited to the DAPE provisions, and the research did not focus on the PE provisions in general. The focal point of the study was specifically on SA subsidiaries acting as dependent agents for its parent companies located in foreign jurisdictions, thereby creating deemed PEs for the foreign parent companies in SA based on the relevant criteria set out in Article 5(5) of the OECD MTC. The research study further explored specific French court cases that focussed on the interpretation of the DAPE provisions in the relevant DTAs and commented on the appropriateness of the decisions reached in these cases. The primary objective of the research was to determine how the DAPE provisions should be interpreted for purposes of SA’s domestic law, as well as its DTAs concluded with both France and Ireland. The research study therefore concluded with an interpretation of a case study based on a similar set of facts to the foreign court cases explored, where an SA subsidiary acted as a dependent agent on behalf of its foreign parent company. The conclusion reached on the appropriate interpretation for domestic law purposes differed significantly to the interpretation for purposes of the DTAs as a result of the significant amendments that were made to the DAPE provisions in the 2017 MTC.Thesis (MCom) -- Faculty of Business and Economic Sciences, School of Accounting, 202