Acacia dealbata invasion and clearing in Upper Tsitsana communal areas of South Africa: human perceptions and ecological impacts
- Authors: Coka, Nwabisa
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434876 , vital:73113
- Description: The number of invasive alien plants in South Africa and globally continue to increase mostly due to increased human movement and climate change. It is estimated that approximately 10 000 hectares of South Africa’s terrestrial land is invaded by invasive alien species. Recent studies have reported that invasion by invasive alien plants cost South Africa billions of Rands every year through loss of water and ecosystem services. Although much has been done to understanding invasion trends, patterns, and processes in South Africa, little is knowns regarding human benefits linked to alien plant invasion as well as human perceptions regarding management interventions, particularly clearing by the national Working for Water programme. This thesis took a socio-ecological approach to assess (i) local people perceptions and knowledge of Acacia dealbata invasion and clearing, and (ii) extent of grazing grass diversity and composition recovery following A. dealbata clearing. To answer the above-mentioned objectives, both qualitative (face-to-face interviews) and quantitative (vegetation surveys) methods were used in grasslands located in upper Tsitsana catchment, South Africa. Results from the 165 interviews conducted in six villages show that most villagers are aware of A. dealbata in the area, but do not know that it is an invasive alien plant. Respondents accrue several benefits from the plant that include firewood (98% across all villages), construction pools (34% across all villages), and shade (3% across all villages). Respondents identified several costs associated with A. dealbata invasion, such as roots damage to houses (37% across all villages), hindering growth of crops (15% across all villages), and takes up yard space (29% across all villages). Most of the villages ranked the effects of A. dealbata on grazing as highly severe. Villages indicated that the Working for Water clearing programme presents them with socio-economic benefits such as employment and money. Some villagers noted that the clearing of A. dealbata in the area restores grazing grass (62% across all villages) and water (32% across all villages). Based on these interview survey results, the study concludes that A. dealbata has both costs and benefits that support local people’s livelihoods; therefore, its management should consider views for local users. Grass surveys conducted in 1 m2 quadrats that were replicated 15 times across four paired A. dealbata cleared and grassland sites showed that the removal of A. dealbata facilitates the recovery of native grasses. Of the 14 different grazable grass species that were identified across all quadrats only one (Bulbostylis sp.) is not palatable to livestock. Although grass cover was significantly (p < 0.05) higher in the grasslands than the cleared patches, grass richness was significantly (p < 0.05) higher in the cleared patches an indication that recovery of different grasses is taking place. Based on these vegetation survey results; the study concludes that recovery of grazing grasses after A. dealbata clearing four years ago is following a positive trajectory as the cleared sites are looking like the grassland sites. Overall, the study recommends that management of A. dealbata in Tsitsana landscape requires a socio-ecological approach to understand user benefits whilst at the same time developing measure to control the plant. The study has provided evidence that A. dealbata clearing facilitates passive restoration of grazing grass and local villages are aware of these restoration benefits. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2024
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- Date Issued: 2024-04-04
Application of the modified pitman and swat models for groundwater recharge estimation in the upstream area of the Uitenhage artesian basin, South Africa
- Authors: Wasswa, Peter
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435400 , vital:73154
- Description: The world's most plentiful source of freshwater is thought to be groundwater. During extended dry times, it serves as an essential storage component and guards against environmental catastrophes. Despite its critical functions in the aforementioned scenarios, it is often insufficiently understood and inadequately managed. As a result, it calls for the adoption of integrated methods to comprehend the dynamics of groundwater recharge. Thus, the current study evaluated the applicability and suitability of the Modified Pitman and SWAT models for groundwater recharge estimation in the upstream area of UAB for the period that spanned from 1993 to 2021. It was achieved by using a qualitative conceptual-perceptual model to inform the two hydrological models, Modified Pitman, and SWAT. The developed qualitative conceptual-perceptual model depicted the dominancy of irregularly folded and fractured TMG rock outcrops coupled with fault systems in the upstream area. In the downward section, TMG is overlaid by the aquiclude from the Uitenhage Group which is responsible for the artesian conditions. Groundwater potential zones were classified as Poor, Fair, Good, and Excellent, with 65.4% and 8.7% of the upstream area attributed to Good and Excellent zones respectively. Both Modified Pitman and SWAT predicted decreasing rates of groundwater recharge in the upstream area over time, though Mann-Kendal trend tests done at 5% signifance level depicted significant decreasing rates in SWAT predicted recharge compared to Modified Pitman predicted recharge. The two models did also predict recharge and other water balance components with differing peaks, lows and timings. Modified Pitman predicted mean annual recharge of 63.3-92.8 mm where as SWAT predicted mean annual recharge of 14.4-182.8 mm. In reference to earlier findings within TMG areas, estimated percentages of groundwater recharge were close to those simulated by both Pitman and SWAT models. Modified Pitman and SWAT models appear to both be reasonable tools to estimate recharge in TMG setting, producing relatively similar results to one another and to other regional estimates. Since the current study estimated low recharge rates (Modified Pitman; ~9.3-13.6% MAP), (SWAT; ~2.1-26.7% MAP) which are close to those predicted in other TMG areas, the study recommends exercising caution when developing a water supply strategy in the current study area. The recharge rates within the pertinent recharging areas should be considered when designing and sitting abstraction points such as boreholes and a sustainable abstraction rate in any one borehole for improved sustainable management of groundwater resources. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2024
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- Date Issued: 2024-04-04
Aptamer-based biosensor for prostate specific antigen detection using cobalt phthalocyanine-exfoliated graphite composites
- Authors: Benise, Emihle
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434850 , vital:73110
- Description: The work focuses on the development of biosensors and their use for the detection of prostate specific antigen (PSA). Four cobalt phthalocyanines (CoPcs) complexes: (1) cobalt tetra pyridyloxy phthalocyanine, (2) cobalt tetra acetamidophenoxy phthalocyanine, (3) cobalt tris(acetamidophenoxy) mono benzoic acid phthalocyanine, and (4) cobalt tris(acetamidophenoxy) mono propionic acid phthalocyanine, an exfoliated graphite (EG), and aptamer are used to make probes for PSA detection. Each complex is π-π stacked onto the EG to form EG-CoPc(π-π) hybrid which was used to modify a glassy carbon electrode (GCE). EG and CoPc were also used to modify the GCE sequential (seq) with CoPc on top to give GCE-EG-CoPc(seq). For the detection PSA, PSA specific aptamer was either sequential added or covalently linked to complexes 3 and 4 on the modified electrodes and was only sequentially added onto complexes 1 and 2 modified electrodes. Electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) were the techniques used for the detection of PSA. The electrodes were found to be selective in bovine serum albumin, glucose and cysteine and stable when 50 DPV scans were run. Electrodes gave good % recovery when human serum was spiked with different PSA concentrations. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
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- Date Issued: 2024-04-04
Attitudes and achievement in statistics: a meta-analytic and functional near-infrared spectroscopy approach
- Authors: Wagenaar, Emma Kate
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435490 , vital:73162
- Description: Statistics anxiety describes the extensive worry and apprehension that students may experience when faced with statistics content as part of their university curriculums. Student’s perfunctory disposition towards statistics has been indicated to negatively affect performance outcomes in statistics courses. Two meta-analyses were conducted to investigate the relationship between statistics anxiety and achievement in statistics. The first meta-analysis was inclusive of 22 studies investigating the relationship attitudes towards statistics and achievement, whilst the second meta-analysis focused on the relationship, primary amongst Psychology students. Student’s attitudes towards statistics were measured using the Survey of Attitudes Towards Statistics (SATS), whilst achievement in statistics courses was quantified using different outcome measures. Finding from the meta-analysis were supplemented by cortical mapping of the neural correlates of statistical reasoning using functional near-infrared spectroscopy (fNIRS). Results from the meta-analysis indicated a small significant relationship between university students’ Affect, r = 0.28, Value, r = 0.22 and Difficulty, r = 0.18, and subsequent achievement in statistics courses. A medium significant relationship between Cognitive Competence, r = 0.31, and achievement was also noted. Findings from the second meta-analysis, indicated a medium, significant relationship between Affect, r = 0.32, and Cognitive Competence, r = 0.35, and achievement. Moreover, a small significant relationship was found between Value, r = 0.24, and Difficulty, r = 0.23, in relation to achievement in statistics courses. Case study analysis of the neural correlates of statistics reasoning revealed varied signal quality findings of cortical mapping of the neural correlates of statistics in the dorsolateral prefrontal cortex (DLPFC). Moreover, seed-based correlation analysis indicated cortical activation of the dorsolateral prefrontal cortex paired with diverse prefrontal regions. Recommendations from the study include improvements to the fNIRS research design and the inclusion of larger samples to investigate the cortical mapping of the DLPFC in relation to statistics reasoning and statistics anxiety. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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- Date Issued: 2024-04-04
Case in modern standard Arabic
- Authors: Ghammaz, Hamzah Saleh Theyab
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435593 , vital:73171 , DOI 10.21504/10962/435593
- Description: This thesis provides a novel account of case checking in Modern Standard Arabic (henceforth MSA). It argues against the concept that nominative case in topic and comment structures is default. Default or inherent case is not related to case filter, nor is it assigned by any syntactic method. Some linguists claim that the default case in Arabic language is employed only when no case assigner is available. I argue, in light of the minimalist program (henceforth MP), that default (inherent) case is always a problem for syntactic theory and that the nominative case which the topic and comment sentences bear is valued by a functional head. The topic and comment constructions contain a predicational head (Pred)- a functional head, that is equivalent to vP which occurs in verbal constructions. The head of PredP is accountable for nominative case value on the topic and comment structures. This thesis also provides a novel paradigm regarding the clitics that appear at the end of verbs in MSA. This paradigm proves that these clitics are not agreement, tense, nor mood markers but rather Verbal Case markers and it provides a minimalist program account to explain case checking on verbs in MSA. Regarding sentence initial DP, and contra to the proposal that in SVO sentence initial DP is a subject, I have scrutinised the nature of this DP and provided enough evidence that it is a topic. Additionally, I have investigated the relationship between agreement asymmetry and the position of the subject in MSA from the minimalist feature inheritance account viewpoint. Mainly, I reviewed null pro hypothesis which proved to be redundant to account for the derivation of VSO or SVO word orders. I have also proved what were considered agreement markers are not agreement markers but resumptive pronouns. Finally, I proved that there is not agreement asymmetry in MSA. Agreement pattern in MSA results from the agree operation and it is achieved under Probe-Goal alignment; regardless of whether the Goal is raised up to Spec-TP or remains in situ (Spec-VP), the agreement is not supposed to change. This conclusion is in harmony with the principles of MP Agree Theory. , Thesis (PhD) -- Humanities, Linguistics and Applied Language Studies, 2024
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- Date Issued: 2024-04-04
Computational design for genome reduction of Lactococcus lactis towards microbial chassis development
- Authors: Hamese, Saltiel
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435321 , vital:73147
- Description: Access restricted. Expected release date 2026. , Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2024
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- Date Issued: 2024-04-04
Developing a community of practice to promote the use of biological control in the integrated management of Prosopis in South Africa
- Authors: Van Staden, Gretha
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434998 , vital:73122
- Description: Prosopis spp. are non-native species present in the arid parts of southern Africa. These trees originated in the Americas and were first introduced as a source of fodder, shade, and wood, but have become invasive, negatively impacting local biodiversity, and disrupting the delivery of ecosystem services. Some species of Prosopis hybridise freely, complicating identification and subsequent control. The control of Prosopis in the Northern Cape Province of South Africa is still contentious, because of the perceived benefits to some landowners. The effectiveness of biological control agents to control the spread of Prosopis has been quantified, more damaging agents have been considered in recent years because of the continued increase in Prosopis density. Research into the establishment of a Community of Practice (CoP) to address the differences in perceptions regarding the control of Prosopis in the Northern Cape Province is considered an appropriate starting point to conceptualise the challenges to the successful integrated management of Prosopis. As farmers are the main stakeholders involved with Prosopis control, understanding the role of farmers and the functioning of farming enterprises in the Northern Cape is imperative for the development of both a CoP as well as the appropriate management of Prosopis. To foster engagement with as many stakeholders as possible, workshops dealing with biological control as part on an integrated approach to the control of Prosopis were held in towns in the Northern Cape Province: Groblershoop, Brandvlei, Kenhardt, Upington, Prieska and Williston. Some of the main concerns of the landusers include the host specificity of the released biocontrol agents, as well as increased transparency and communication. This is especially in regards to the research on present and future biological control agents that will possibly improve the perceptions of stakeholders. The mechanical harvesting and use of biomass as a control method was supported, especially where farmers were removing Prosopis from their properties, leaving large amounts of biomass in the veld. Continued research into Prosopis in the Northern Cape needs to consider the possibility of secondary invasions, especially in areas where native bush encroachment is already a concern. The impact of clearing in terms of natural grazing and animal improvement needs to be quantified, to conceptualise the importance of maintaining better veld quality versus using Prosopis for fodder. Biological control targeting not only the reproductive output of the trees, but also the standing biomass has support from the majority of the land users in the Northern Cape Province following these workshops and this study shows the importance of a socio-ecological approach to the control of landscape scale invasion. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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- Date Issued: 2024-04-04
Educators’ experiences of psychosocial support workshops during COVID-19 in Eastern Cape, South Africa
- Authors: Mabasa, Rendani Mirriam
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435457 , vital:73159
- Description: There is growing awareness of the value and central role of immediate and long-term mental health and psychosocial support (MHPSS) interventions, especially during times of crisis such as Covid-19. The World Health Organization has identified the education sector as a crucial intervention site for public mental health promotion. In collaboration with members of the Makhanda education community, the Rhodes University Community Engagement office identified psychosocial support for educators and educational practitioners as a key societal and educational challenge. Focusing specifically on the experiences of educators, this study sought to solicit their experiences of MHPSS workshops in a rural city of the Eastern Cape province of South Africa. Focus groups with educators and educational practitioners in non-government organisations, care centres and other educational settings who participated in the psychosocial support workshops were conducted. Data was analysed using community psychology’s social action framework. Four broad themes emerged from the data: the responsibilisation of educators during and post-Covid-19, educators’ resilience and support for each other, educators’ mental health promotion through psychosocial support workshops, and top-down intervention strategies that fall short in addressing educators’ and learners’ needs. This study demonstrates the value of university-community partnerships in education settings which are key sites for public mental health promotion. In this study, I advocate psychosocial support as a standard practice available for educational practitioners and show how professional training programmes in higher education can be responsive to societal challenges via collaborative approaches. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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- Date Issued: 2024-04-04
Elucidation of the roles of the carbonic anhydrase enzymes, CanA & CanB, in the physiology of Mycobacterium smegmatis
- Authors: Jackson, Gabriella Teresa
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435299 , vital:73145
- Description: The bacterial pathogen Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB) and one of the leading infectious causes of death globally. The success of Mtb as a pathogen depends on its ability to detect and respond to a variety of physical and chemical stresses it encounters during infection of its human host. These environmental stresses include shifts in temperature, oxygen concentration, osmolarity and nutrient availability. Mtb is, in addition, exposed to changes in pH and CO2 concentration in the intracellular and extracellular environments it inhabits, which the bacterium has to adapt to in order to ensure its growth, survival and/or persistence during infection. Carbonic anhydrases (CAs) are a widely distributed family of enzymes that catalyse the reversible hydration of carbon dioxide (CO2) to bicarbonate (HCO3−) in the reaction: CO2 + H2O ⇄ HCO3− + H+. In microbes, CA activity is important for the activity of enzymes involved in carbon fixation as well as for maintaining pH homeostasis. Mtb is known to express three CAs, encoded by the Rv3588c, Rv1284 and Rv3273 genes (canA, canB and canC, respectively). The role(s) of these CA enzymes in the physiology of Mtb and other mycobacterial species, such as Mycobacterium smegmatis (Msm), has not been elucidated to date. To gain insights into the function of the CanA and CanB enzymes in mycobacterial species, we generated both canA and canB knockdown (KD) and knockout (KO) mutants in the fast-growing mycobacterial species, Msm, and analysed their growth phenotypes under several growth conditions where CA activity is known to be required. Notably, Msm lacks the CanC homologue, which makes it an ideal surrogate to focus on CanA and CanB. The Msm canA KD mutant was found to display a growth defect following anhydrotetracycline (ATc)-mediated gene silencing at atmospheric (low) CO2 concentrations [~0.035% CO2 (v/v)]. The growth defect could be rescued by incubating cells at physiological (high) CO2 concentrations [~5% CO2 (v/v)] or by supplementing the growth media with either HCO3− or the metabolic end-products of certain HCO3−-dependent-carboxylase enzymes at low CO2 concentrations. The ability of these compounds to rescue the growth of the canA KD mutants was, however, dependent on the extent of ATc-mediated gene silencing, suggesting that the canA gene is required for Msm growth at both low and high CO2 concentrations. This was confirmed by our findings that canA could only be genetically inactivated when a second copy of the gene was provided on the chromosome in trans, regardless of the CO2 concentration used. In contrast to our observations for canA, no differences in the growth phenotypes of the Msm wild type (WT) and canB KD or knockout (KO) mutant strains were observed following silencing or inactivation of the canB gene at either low or high CO2 concentrations or different pH values. These observations suggest that, in contrast to canA, the canB gene is dispensable for the growth of Msm under standard laboratory growth conditions. The canB KO mutant strain, nevertheless, displayed a slight decrease in its ability to form biofilms when compared to the WT strain, which could be restored by genetic complementation. CanB activity may, therefore, be required to promote bacterial growth and/or survival under biofilm conditions where CO2 diffusion into cells is limited, a phenomenon that has recently been observed in other microbes. Further studies are required to confirm the role of CanB in biofilm formation and to determine how the different CA enzymes cooperate to promote the growth and survival of mycobacterial species in the various environments they are known to inhabit. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2024
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- Date Issued: 2024-04-04
English morphological awareness and reading comprehension in deaf and hearing grade 3 to 7 learners from Lesotho
- Authors: Tšehla, Puleng Magret
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/${Handle} , vital:73169
- Description: There is a noticeable literacy crisis observed in both Deaf and hearing learners from Lesotho. This study investigates the English Morphological Awareness and reading comprehension of 26 Deaf and 82 hearing learners enrolled in grades 3 to 7 in two schools in Lesotho. This study employs a correlational cross-sectional quantitative design. Each participant completed two literacy assessment tasks: a reading comprehension task and a Morphological Awareness task. The Morphological Awareness task encompassed five subtasks that assessed the learners’ inflectional, derivational, and compound awareness. The results of these assessments are analysed through appropriate statistical analyses. In addition, errors made by the Deaf and hearing learners on the literacy assessments are compared and analysed. This analysis determines the types of errors made by each group and identifies the factors that influence these errors. The performance of both groups in terms of task scores, in general, was low. Deaf learners and hearing learners’ performance on the tasks was similar. This outcome contradicts most previous studies, which indicate that Deaf learners typically exhibit lower levels of Morphological Awareness development and reading comprehension compared to their hearing counterparts. The results of this study also suggest that there is a statistically significant relationship between Morphological Awareness and reading comprehension in both groups. Finally, Deaf and hearing learners made similar errors on the tasks. There was some evidence of influence from both the Deaf and hearing learners’ first languages (Sesotho and Lesotho Sign Language, respectively). The study demonstrates the need for more explicit morphological instruction to improve both Deaf and hearing learners’ literacy. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2024
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- Date Issued: 2024-04-04
Functional significance of mixed-species groups for zebra (Equus quagga) in savanna habitats
- Authors: Corry-Roberts, Carys Alexandra
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434925 , vital:73116
- Description: Globally, herbivore populations are facing decline, which threatens their crucial role within the ecosystems they inhabit. Herbivores are essential to ecosystem structure and function because they act as prey for higher trophic levels, cycle soil nutrients, and alter vegetation structure. Understanding the drivers that shape herbivore habitat use and selection are therefore critical for making informed conservation and management decisions. Like all prey species, herbivores must balance a trade-off between acquiring resources and avoiding predation which is influenced by a number of species-specific intrinsic traits and various ecological drivers. Herbivores can also track risk over space and time, and certain habitat structures and landscape features can influence risk perception; this is termed the landscape of fear. To mitigate the risk-reward trade-off, herbivores employ a suite of behavioural responses. Group formation is likely the most well-documented of these responses. However, grouping results in the information-competition trade-off, wherein group members may obtain valuable information regarding the location of resources and/or the risk of predation, but may suffer from increased competition, especially among larger group sizes. Mixed-species groups—an assemblage of two or more species in close spatial association—have the potential to mitigate some of the competitive costs of larger conspecific groups and enhance the anti-predator and/or foraging benefits of grouping. African savannas provide a particularly useful natural laboratory to study mixed-species groups, due to the high diversity of prey species and habitat heterogeneity present. Previous studies have investigated the mixed-species effect within these systems, but have yet to quantify some of the identity-dependent costs and benefits associated with mixed-species herding. Thus, the overall aim of my study was to quantify the functional significance of mixed-species groups for zebra (Equus quagga) herding with two of their most common herding partners, impala (Aepyceros melampus) and wildebeest (Connochaetes taurinus). My study was conducted at multiple spatial scales in the southern portion of the Kruger National Park, South Africa between 2021 and 2022. I found that mixed-species herding altered zebra landscape use, resulting in a quantifiable intensification of habitat use compared to when they herd with conspecifics. I did not observe significant habitat expansion for zebra in mixed-species herds compared to single-species herds, likely because the anti-predator benefits of mixed-species herding convey enhanced foraging opportunities in already-safe habitats. Zebra foraging with impala achieved greater foraging success and experienced lower levels of competition, compared to zebra foraging with wildebeest. However, compared to foraging with conspecifics, the levelled landscape of fear zebra experienced when foraging with wildebeest resulted in increased foraging success across the landscape. My findings highlight the context-dependency of the costs and benefits associated with different herding partners for zebra, and suggest that in mixed-species herds with wildebeest, zebra experience increased potential fitness benefits compared to herding with impala or conspecifics. Overall, the findings of my study suggest that mixed-species herding is an important tool in the suite of anti-predator behaviours employed by prey species, and one with significant implications for survivorship, habitat use, and ultimately, community level interactions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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- Date Issued: 2024-04-04
High-altitude temporary systems and macroinvertebrate composition in La Nina cycle, Maloti-Drakensberg
- Authors: Moyo, Sibusisiwe
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434963 , vital:73119
- Description: The Maloti-Drakensberg Mountain is an important water catchment area for South Africa and Lesotho. It is rich in biodiversity in terms of endemic flora and fauna and has a high density of temporary wetlands in the form of Afromontane tarns and rock pools. There is, however, limited information on the distribution of macroinvertebrates in these ecosystems and environmental factors that drives their composition. To that end, this study investigated macroinvertebrate diversity and the effect of environmental factors on community assemblage in the Maloti-Drakensberg Mountain temporary wetlands, specifically tarns and rock pools. The main aims were to describe the abundance, diversity, and distribution of macroinvertebrates in temporary wetlands in the Maloti-Drakensberg Mountain. Furthermore, it aimed to investigate the effect of environmental variables on habitat structuring, spatial variations, and macroinvertebrate community composition in tarns and rockpools in the Maloti-Drakensberg Mountain. Seventy temporary wetlands (29 tarns and 41 rock pools) were surveyed over a once-off sampling (3 March – 7 April 2022). The wetlands were from 3 provinces including Eastern Cape, Free State, and KwaZulu-Natal. 15278 individual macroinvertebrates from 13 orders, 35 families, and 46 genera were collected and identified. Species accumulation curves incorporating both tarns and rock pools showed that observed results were significantly lower than Chao 1 and Chao 2 estimates meaning that the sampled sites were not enough to provide a comprehensive picture of the biodiversity in the region. This was also observed for rock pools when the temporary wetlands were analysed separately, however, the Chao 1 and Chao 2 values for tarns were almost equal to the observed values implying that sampled sites were enough to give a detailed picture of macroinvertebrate composition in tarns. Tarns and rock pools were significantly different in terms of species richness and Shannon-Wiener diversity index but showed no significant differences for relative abundance and Pielou’s evenness. Of the 35 families identified, 19 were considered core taxa with Dytiscidae and Corixidae being the most dominant. Additionally, there was moderate Nestedness metric based on Overlap and Decreasing Fill (NODF) value of 33.05369, with 32 out of 35 families being idiosyncratic. Predators were the dominant feeding group with omnivores being the least common. Non-Metric multi-Dimensional Scaling (NMDS) and PERMANOVA results showed that tarns and rock pools supported distinctly different macroinvertebrate communities per wetland type and location respectively. Physicochemically, tarns and rock pools were significantly different in terms of water temperature, depth, area, and chlorophyll-a concentration with tarns exhibiting higher values. Temporary wetlands in the sampled localities differed in terms of pH, EC, DO, water temperature, altitude, and phosphate. Principal Component Analysis showed that tarns were positively associated with area and depth whereas rock pools with phosphate. Akaike’s Information Criterion (AICc) selection showed that area, pH, and water temperature were significantly influencing community assemblage in temporary wetlands. Furthermore, area significantly influenced all four measured biodiversity indices: relative abundance, species richness, Pielou’s evenness and Shannon-Wiener Index, with water temperature also influencing relative abundance and altitude, species richness. Overall, the species composition showed that the sites were sampled later in the hydroperiod as evidenced by the dominance of active dispersers. The extended distribution of Prosthetops gladiator in the Eastern Cape highlights the need for extensive surveys to provide valuable insight into the distribution patterns of macroinvertebrates in the region. Furthermore, the interplay between physicochemical variables and biodiversity indices emphasized area, water temperature and pH as significant factors. However, their limited explanatory power suggests that obscure factors also influence the diversity cementing the need for further exploration of these enigmatic systems. Taxonomic challenges, especially regarding large branchiopods, hindered precise species distribution and conservation status determination. This study is the first to provide a comprehensive list of macroinvertebrates from temporary wetlands in the Maloti-Drakensberg Mountain. These results establish a valuable baseline for future biological monitoring studies, particularly in assessing species composition and responses to anthropogenic activities. It is a timeous study considering the sensitivity of these systems to climate change as they act as sentinel sites hence the need for foundational data on which to make future projections. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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- Date Issued: 2024-04-04
Home is in the wandering
- Authors: Purdon, Bradley Michael
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435547 , vital:73167
- Description: Submitted in partial fulfilment of the requirements for the degree of Master of Arts in Creative Writing , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
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- Date Issued: 2024-04-04
Identifying the factors that influence parents and caregivers to commit child maltreatment: systematic review
- Authors: Dipholo, Mamdlalose Emily
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435421 , vital:73156
- Description: Child maltreatment, encompassing various forms of abuse and neglect, poses a significant global public health concern. This study provides a comprehensive examination of the multifaceted dimensions of child maltreatment, including physical, emotional, and sexual abuse, as well as neglect. The impact of maltreatment on the developing child is profound, resulting in a range of adverse physical and mental health outcomes, developmental delays, behavioural challenges, and social difficulties. The aim of this study was to comprehensively review and synthesise peer-reviewed research on the factors influencing parents and caregivers in committing child maltreatment. This systematic review identified the multifaceted factors influencing parents and caregivers to engage in child maltreatment. Using a social ecological framework, ten key themes emerged, namely poverty and lack of access to services, intergenerational transmission of abuse, childhood trauma, substance abuse, domestic violence, neighbourhood violence, cultural practices, social factors, children’s individual factors, and caregivers' mental health concerns. Personal history, caregiver’s mental health, substance abuse, poor awareness of self-protection, and gender emerged as significant individual-level contributors. Non biological caregivers and domestic violence were identified as relationship-level factors. At the community level, poverty, lack of access to services, unemployment, and neighbourhood violence were found to impact child maltreatment. Cultural values and the intergenerational transmission of abuse were reported as influential societal-level factors. The study underscores the complex interplay of personal, environmental, and cultural influences in child maltreatment, highlighting the need for comprehensive strategies to address this critical issue. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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- Date Issued: 2024-04-04
Insights: elucidation of squalene monooxygenase inhibitors for lowering cholesterol in cardiovascular diseases
- Authors: Leoma, Mofeli Benedict
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434861 , vital:73111
- Description: Statins have been used to lower high cholesterol levels in the past few decades. However, several studies have shown that some people taking statins experience side effects over time, especially elderly patients, women of childbirth possibility, and children. Several studies have shown that the majority of people with underlying cardiovascular complications caused by high cholesterol are at a greater risk of fatality due to COVID-19, regardless of age and sex. The literature suggests that antimycotic squalene monooxygenase inhibitors, terbinafine and its derivatives, and anticholesterolemic squalene monooxygenase (SM) inhibitors could be another option and a safer remedy for lowering cholesterol in mammals. Molecular docking calculations, molecular dynamics (MD) simulations, molecular mechanics generalized born surface area (MM-GBSA) calculations, quantum mechanics/molecular mechanics calculations (QM/MM), and density functional theory (DFT) calculations were used in this study. An early stage in drug discovery, in which small molecular hits from high- throughput screening (HTS) are evaluated and undergo limited optimization to identify promising lead compounds, is referred to as lead generation. To address the first step of lead generation, the number of compounds to be tested was narrowed down, and the hit compounds that could be taken for further tests were obtained. Thus, the molecular docking technique was taken advantage of, which assisted us in identifying the antimycotic ligand SDZ 18, which had a good binding affinity of about -8,4 kcal mol−1. Another widely employed strategy, the molecular mechanics-generalized born surface area (MM-GBSA), was used to investigate the binding free energies of the protein-ligand complexes to validate the binding affinities obtained from molecular docking. Despite the excellent docking results, it must be emphasized that the stability of the ligand in the binding pocket must be investigated. To address this, the protein-ligand complexes were then taken through molecular dynamics for 100 ns simulations calculations which showed that the inhibitors stayed in the binding pocket with the RMSD values below 3.5 Å for most systems. This provided insight into a realistic model because the docked complexes were placed in conditions closer to the physiological environment at 300 K and 1.01325 bar, and in an explicitly solvated dynamic environment. Density functional theory (DFT) at the B3LPY level of theory using the standard 6-31G(d,p) basis set was used to assess the reactivity and other properties of the SM inhibitors. ONIOM calculations were performed to explain what was happening at the microscopic level by calculating the total energy of the complex. The aim of this project was to efficiently uncover the non-physical aspects of SM inhibitors with the help of computational techniques to identify new drugs that can lower high cholesterol levels. From a theoretical perspective, the results obtained from docking indicated that the antimycotic ligands SDZ SBA 586 18 and TNSA 84 (trisnor-squalene alcohol ) have good binding affinities, and the MM-GBSA method provided free energy calculations. MD results indicated that the stability of the ligand in the binding pocket was achieved during the 100 ns simulations. The HOMO-LUMO energy gaps obtained from DFT calculations provided information on the reactivity of the ligands. Other insights into the protein-ligand complexes were obtained from a hybrid ONIOM QM/MM study. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
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- Date Issued: 2024-04-04
Interlingual and intercultural communication discordances as impediments to the provision of quality public healthcare services: cases of Cecilia Makiwane Hospital, Nkqubela Chest Hospital and Frere Hospital
- Authors: Hlitane, Nkosekaya
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435501 , vital:73163
- Description: This study seeks to explore interlingual and intercultural discordances between clinicians and patients during treatment processes in selected public hospitals in the Eastern Cape. The two languages under investigation are English and isiXhosa. Intercultural communication refers to a phenomenon in which people who speak different native languages are engaged in a conversation (Gudykunst 1993). , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
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- Date Issued: 2024-04-04
Investigating changes in pineapple (Aananas comosus) cultivation in the Eastern Cape, South Africa, from 1984 to 2020
- Authors: Marriner, Paul Joseph
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435354 , vital:73150
- Description: Land use and land cover change (LULCC) resulting from agricultural activities have significantly impacted landscape transformation and fragmentation. The Albany Thicket Biome in the Eastern Cape Province stands out for its exceptional vegetation diversity and remarkable rates of species endemism. However, the relationship between agricultural activities and the Albany Thicket Biome has not received sufficient attention in the literature, creating a significant gap in understanding the extent of landscape transformation and the vegetation's recovery rate. This study aims to address this gap by utilising remote sensing technologies to investigate the LULCC specifically caused by pineapple cultivation in the Lower Albany area between 1984 and 2020. Analysis, using remotely sensed imagery and spatial analytical tools, provide accurate identification of pineapple fields and enable monitoring of their effects on LULCC dynamics across a wide spatial and temporal scale. Complementary field assessments examined the impacts of pineapple cultivation on land use and cover. Twelve image classifiers were tested to identify the most appropriate technique for mapping pineapple fields, and the Supervised Pixel-based Support Vector Machine (SVM) image classifier was found to be the most suitable. Utilising Landsat 4, 5, 7, and 8 satellite imagery, 27 land cover maps were created, spanning the period from 1984 to 2020. Additionally, field verification was conducted at 59 randomly generated sites to validate the findings. Spatial analysis of the data revealed that the pineapple industry in the study area has expanded by 733 hectares since 1984. Significant land use changes were observed, including converting land to wildlife ranches, grazing areas, and alternative agricultural practices. The land cover analysis identified the emergence of pioneer species in former pineapple fields, suggesting the potential for Albany Thicket regrowth if appropriately managed. This research contributes to a better understanding of the impacts of pineapple cultivation on the Albany Thicket Biome and provides valuable insights for land use planning and monitoring efforts. A comprehensive assessment of LULCC dynamics can be achieved by utilising remote sensing techniques, informing sustainable land management practices in the study area and beyond. , Thesis (MSc) -- Faculty of Science, Geography, 2024
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- Date Issued: 2024-04-04
Investigating playing-related musculoskeletal disorders in South African instrumental musicians
- Authors: Green, Erryn Mae
- Date: 2024-04-04
- Subjects: Musculoskeletal disorder , Musculoskeletal system Diseases , Musicians Wounds and injuries , Musicians Health and hygiene , Human engineering South Africa , Musicians Health risk assessment , Biomechanics , Musical instruments , Music genre
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435310 , vital:73146
- Description: This study, one of the first studies in SA to investigate PRMD in a wideranging sample of instrumental musicians using a validated self-report tool, shows that PRMDs are highly prevalent among a range of SA musicians and have a considerably negative effect on musicians’ performance ability and quality of life. However, making inferences about most affected genre or instrumental group was challenging due to the small sample sizes in some categories. The results from this study confirm that the nature of PRMD development is indeed multi-factorial, with factors numerous individual and playing-related factors playing a role in the development of PRMDs in SA musicians. Better support and education on health promotion for musicians, including awareness of and prevention strategies for PRMDs in the SA context are needed which may reduce the prevalence of PRMDs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
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- Date Issued: 2024-04-04
Investigating unimodal isolated signer-independent sign language recognition
- Authors: Marais, Marc Jason
- Date: 2024-04-04
- Subjects: Convolutional neural network , Sign language recognition , Human activity recognition , Pattern recognition systems , Neural networks (Computer science)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435343 , vital:73149
- Description: Sign language serves as the mode of communication for the Deaf and Hard of Hearing community, embodying a rich linguistic and cultural heritage. Recent Sign Language Recognition (SLR) system developments aim to facilitate seamless communication between the Deaf community and the broader society. However, most existing systems are limited by signer-dependent models, hindering their adaptability to diverse signing styles and signers, thus impeding their practical implementation in real-world scenarios. This research explores various unimodal approaches, both pose-based and vision-based, for isolated signer-independent SLR using RGB video input on the LSA64 and AUTSL datasets. The unimodal RGB-only input strategy provides a realistic SLR setting where alternative data sources are either unavailable or necessitate specialised equipment. Through systematic testing scenarios, isolated signer-independent SLR experiments are conducted on both datasets, primarily focusing on AUTSL – a signer-independent dataset. The vision-based R(2+1)D-18 model emerged as the top performer, achieving 90.64% accuracy on the unseen AUTSL dataset test split, closely followed by the pose-based Spatio- Temporal Graph Convolutional Network (ST-GCN) model with an accuracy of 89.95%. Furthermore, these models achieved comparable accuracies at a significantly lower computational demand. Notably, the pose-based approach demonstrates robust generalisation to substantial background and signer variation. Moreover, the pose-based approach demands significantly less computational power and training time than vision-based approaches. The proposed unimodal pose-based and vision-based systems were concluded to both be effective at classifying sign classes in the LSA64 and AUTSL datasets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
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- Date Issued: 2024-04-04
It's all in your head
- Authors: Namukuta, Sonia Charity Sajjabi
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435536 , vital:73166
- Description: My thesis is a collection of short stories that delve into the multifaceted nature of death, with a specific emphasis on murder, violence, death and their profound aftermath, including themes of loss, grief, and trauma. These stories offer diverse perspectives, narrated by perpetrators, voiceless victims, and those left to pick up the shattered pieces. Additionally, some stories are seen through the eyes of those tasked with handling the bodies. Often set in unnamed locations, they delve into imaginary and fantastical worlds, while remaining grounded in recognisable situations and spaces. I draw inspiration from popular and genre fiction such as horror, crime fiction and true crime stories, but approach my writing from a psychological lens, employing stylistic experimentation to challenge readers' expectations. The power of silence is a recurring motif. Rather than focusing on unearthing facts or revealing the "truth" like crime fiction often does, my narratives delve into what isn't or at times cannot be told — the unsayable. Some of my stories explore silence inherent in violence, grief, and the inability to articulate one's experience in the face of a violent act or a life prematurely ended. Others delve into the silence of untold stories and the dark secrets of the perpetrators. By exploring these contrasting perspectives, I aim to offer a nuanced exploration of death and its aftermath. The writing styles of Stephen Graham Jones, Lydia Davis, and Kuzhali Manickavel influence my work. Lydia Davis, known for her mastery of very short, flash fiction, ranging from single sentences to a paragraph or two, inspires me with her precise observations of the human condition. Her minimalist prose, carefully selecting and arranging words and sentences, encapsulates the power of less-is-more storytelling. Manickavel creates surreal yet tangible worlds, combining idiosyncratic, intense and eerie elements with unfiltered expression. Drawing from her ability to blur the lines between the surreal and the real, I infuse my stories with a sense of disquieting authenticity. Stephen Graham Jones stands out for his ability to explore morbid themes in a compelling and unconventional manner. His experimentation with horror fiction tropes, the visceral realism of his prose, and his complex characters inspire me to capture the unsettling feeling that something dreadful has occurred without explicitly detailing the facts and intricacies. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
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- Date Issued: 2024-04-04