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Current harmonic compensation of nonlinear loads in a three phase, four wire system

  • Authors: Mtakati, Sibulele Morgen
  • Date: 2023-12
  • Subjects: Harmonics (Electric waves) , Electric power system stability , Electric power -- Conservation
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/66574 , vital:75608
  • Description: Nonlinear loads, in low voltage distribution networks, inject current harmonics which affect the quality of supply voltages. In this work, the power usage of a university student residential complex was logged over a four day period for analysis of harmonic currents injected by nonlinear loads. Student residents use nonlinear loads such as lighting, televisions, computer power supplies, and other household appliances. The harmonic analysis was performed on the quality of voltages in the university’s distribution network, the level of current distortion in the load current and the contribution of triplen harmonics to the neutral current. Standards such as the NRS048-2 (2007), IEEE-519 (2014) and IEC61000-3-2 (2009) are helpful in regulating harmonic levels in the distribution network, however, they cannot guarantee good quality supply. This work further investigates two methods of current harmonic cancellation, i.e. a shunt passive and an active current harmonic cancellation technique. A passive power filter was designed, built, and evaluated for a given nonlinear load to provide selective filtering of the dominant current harmonics. A four branch, shunt, passive filter was considered in this work for implementation in a three phase four wire distribution network due to its attractive possibility to be tuned to two different harmonic components with a minimum number of passive elements. While passive filters may be inexpensive, they suffer from several disadvantages, such as providing fixed compensation, performance that is source impedance dependent, has an inherent risk of system resonance and detuning due to ageing and component variation. To overcome the disadvantages of passive filters, a shunt connected active power filter was designed, built and evaluated to provide adjustable, wide bandwidth and dynamic correction to nonlinear loads for the compensation of harmonic currents, reactive power, and neutral currents. The controller used was an indirect FFT-based technique with a second order generalized integrator (SOGI) filter for voltage synchronization. It was digitally implemented in an FPGA programmed in VHDL to allow for fast parallel processing of input variables. , Thesis (M.Eng) -- Faculty of Engineering, the Built Environment, and Technology, School of Engineering, 2023
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  • Date Issued: 2023-12

Current harmonic compensation of nonlinear loads in a three phase, four wire system

  • Authors: Mtakati, Sibulele Morgen
  • Date: 2023-12
  • Subjects: Electric utilities -- Quality control , Electric power systems , Electric power system stability
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/66581 , vital:75607
  • Description: Nonlinear loads, in low voltage distribution networks, inject current harmonics which affect the quality of supply voltages. In this work, the power usage of a university student residential complex was logged over a four day period for analysis of harmonic currents injected by nonlinear loads. Student residents use nonlinear loads such as lighting, televisions, computer power supplies, and other household appliances. The harmonic analysis was performed on the quality of voltages in the university’s distribution network, the level of current distortion in the load current and the contribution of triplen harmonics to the neutral current. Standards such as the NRS048-2 (2007), IEEE-519 (2014) and IEC61000-3-2 (2009) are helpful in regulating harmonic levels in the distribution network, however, they cannot guarantee good quality supply. This work further investigates two methods of current harmonic cancellation, i.e. a shunt passive and an active current harmonic cancellation technique. A passive power filter was designed, built, and evaluated for a given nonlinear load to provide selective filtering of the dominant current harmonics. A four branch, shunt, passive filter was considered in this work for implementation in a three phase four wire distribution network due to its attractive possibility to be tuned to two different harmonic components with a minimum number of passive elements. While passive filters may be inexpensive, they suffer from several disadvantages, such as providing fixed compensation, performance that is source impedance dependent, has an inherent risk of system resonance and detuning due to ageing and component variation. To overcome the disadvantages of passive filters, a shunt connected active power filter was designed, built and evaluated to provide adjustable, wide bandwidth and dynamic correction to nonlinear loads for the compensation of harmonic currents, reactive power, and neutral currents. The controller used was an indirect FFT-based technique with a second order generalized integrator (SOGI) filter for voltage synchronization. It was digitally implemented in an FPGA programmed in VHDL to allow for fast parallel processing of input variables. , Thesis (MEng) -- Faculty of Engineering, the Built Environment, and Technology, School of Engineering, 2023
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  • Date Issued: 2023-12

Dietary assessment of Cape Gannets (Morus capensis) and African Penguins (Spheniscus demersus) in Algoa Bay using molecular scatology

  • Authors: Bowmaker - Falconer, Kezia , Von Der Heyden, Sophie
  • Date: 2023-12
  • Subjects: Gannets , Gannets -- Food , Sea birds -- South Africa -- Bird Island, Algoa Bay.
  • Language: English
  • Type: Master's theses
  • Identifier: http://hdl.handle.net/10948/62420 , vital:72675
  • Description: Seabirds are important marine sentinels, providing valuable information about ecosystem health and condition. Dietary studies of seabirds can inform on ecosystem functioning through identifying the condition and changes occurring in their surrounding environment. Dietary studies are also crucial as they can identify threats that seabirds face. Until recently, the diets of southern African endemic and Endangered Cape Gannets Morus capensis and African Penguins Spheniscus demersus were solely investigated through stomach content analyses, which allows for the identification and quantification of prey remains. To overcome some of the limitations associated with stomach content analysis, stable isotope and fatty acid analyses were proposed. However, these methods still require bird handling and thus impose some stress on the birds. DNA metabarcoding of faecal matter shows promise as a completely noninvasive method for seabird dietary studies. This thesis first examined whether DNA metabarcoding could be used to determine the diet of Cape Gannet and African Penguin breeding in Algoa Bay, South Africa. Then, this method was used to investigate the influence of intrinsic (both seabird species) and extrinsic (African Penguins) factors on the diet of the two seabird species. For the first data chapter, stomach content samples and faecal matter were collected concurrently from breeding Cape Gannets and African Penguins on Bird Island. DNA was successfully extracted from most faecal matter samples and the primers (18S_SSU, 16S_Fish) used for group, taxa and fish prey identification allowed amplification of prey DNA for both study species. A similar piscivorous diet was determined by both dietary methods for Cape Gannets with Sardine Sardinops sagax and Atlantic Saury Scomberesox saurus dominating the diet. Sardine also dominated the African Penguin diet in both dietary methods. In addition, DNA metabarcoding in African Penguins revealed a more diverse diet compared to the one determined by stomach content analysis. This was likely due to the limitations on the allowed number of stomach content samples to be collected for that Endangered species. Non-invasive DNA metabarcoding of faecal matter was then used to investigate whether the diet varied with breeding stages (incubation, chick-rearing) and age classes (chick-rearing adults, chicks) in both seabird species, but also breeding colonies (Algoa Bay: Bird Island, St Croix Island) in African Penguins. DNA metabarcoding revealed that breeding stages influenced the diet of Cape Gannets and African Penguins on Bird Island where prey species diversity was greater for incubating adults. On the contrary, the diet of incubating and chick-rearing penguins on St Croix Island was similar. When comparing the diet of African Penguins between Bird Island and St Croix Island, there was an increased overlap in diet composition between incubating and chick-rearing adults on St Croix Island when compared to Bird Island. Importantly, DNA metabarcoding indicated an increase in fishery interactions in Algoa Bay, particularly for Cape Gannets and the hake Merluccius spp. fishery, where the contribution of hake to chick-rearing adults and chick diet was considerably greater than incubating adult diet. In this study, I showed that DNA metabarcoding of faecal matter provides an opportunity for non-invasive dietary studies in two southern African endemic and Endangered seabird species. Incorporating non-invasive methods as a complement to other dietary methods for monitoring seabird trophic ecology is crucial when considering the worsening status of several seabird species. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2023
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  • Date Issued: 2023-12

Eco-leadership determinants necessary for effective sustainability implementation

  • Authors: May,Jodé
  • Date: 2023-12
  • Subjects: Retail trade -- Management , Leadership -- South Africa , Sustainability
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/65683 , vital:74228
  • Description: Sustainability is regarded globally as one of the key focus areas for organisations and requires also considering environmental and social performance in addition to economic performance. Eco-leadership is required to ensure operations impact society and the environment in a positive manner, in particular in the retail sector as customers have become conscious of their purchases being produced sustainably. The main objective of this study was thus to explore eco-leadership determinants necessary for sustainability implementation in retail organisations. The research was aimed at expanding knowledge about how retailers can implement or improve their sustainability status by following an eco-leadership approach. A literature review was conducted on what leadership in organisations entailed and how it can be described in terms of leaders’ characteristics, work practices and decisions. In addition a review on, leader qualities and leadership styles in general and of change leaders such as eco-leaders, sustainability strategies from both an environmental and socially responsible view in general and of the retail sector, was provided. The study followed a qualitative research approach using purposive sampling to identify the 11 participants from across the provinces in South Africa and retail product categories comprising of two hard-line retailers, five soft goods and consumables retailers, three FMCG retailers and one art retailer. A semi-structured interview guide was utilised to gather primary data using face-to-face, telephonic and email interviews. Content and constant comparative analysis was used to analyse the data. It appears that retailers ascribe eco-leadership in relation to resource management-, being people centred and practising sustainability leadership. All retailers seem to demonstrate their commitment to eco-leadership and serve society. Their sustainability status is publicised via digital and print media or visually displayed in-store. They practise eco-leadership as it is beneficial for their reputation or to ensure business continuity. Retailers use innovation and incorporate eco-leadership into their business models and have further plans to improve their sustainability. , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Management Sciences, 2023
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  • Date Issued: 2023-12

Effects of annealing on the structural and optical properties of nanostructured TiO2

  • Authors: Talla, Assane , Urgessa, Zelalem
  • Date: 2023-12
  • Subjects: Titanium dioxide , Nanostructured materials , Nanotubes
  • Language: English
  • Type: Doctorial theses , text
  • Identifier: http://hdl.handle.net/10948/62655 , vital:72907
  • Description: In this thesis, the structural, morphological and optical properties of titanium dioxide (TiO2) are investigated. Titanium dioxide (TiO2) nanotubes are prepared by anodic oxidation of titanium foil. The as-anodised samples are thermally annealed at various temperatures in nitrogen, air, oxygen and vacuum. The purpose is to study how the annealing conditions affect the properties of the nanostructures, including the anatase to rutile phase transformation. In all annealing atmospheres, except in vacuum, the dominant phase is found to be anatase when annealing is performed up to 600 oC. Above 700 oC the rutile phase becomes dominant. The anatase phase is stable above 600 oC in vacuum and does not evolve significantly up to 900 oC. The morphologies of the tubes tend to deteriorate with increased annealing temperature, in nitrogen, air and oxygen atmospheres, due to sintering effects. However, the integrity of the nanotubes is maintained up to 900 oC in vacuum. The photoluminescence (PL) spectra suggest mainly the presence of oxygen vacancies and self-trapped excitons, with respective emission bands around 2.5 eV and 2.3 eV. The results show that both the annealing temperature and atmosphere strongly influence the crystalline and optical properties of the TiO2 nanotubes. In addition, the phase transformation from anatase to rutile for samples annealed in an oxygen-rich environment is investigated in detail. Complementary structural information obtained from transmission electron microscopy and Raman analysis for oxygen-annealed samples reveals that the nucleation of the rutile phase starts from the titanium substrate and then propagates along the tubes. The results provide suitable annealing conditions to control the phase content and morphology of anodic TiO2 nanotubes. The PL characteristics of bulk crystalline anatase TiO2, namely virgin and hydrogen-annealed at 600 oC for 1 h, are studied. The low temperature PL spectra at 5.5 K shows near band edge (NBE) emissions with two dominant lines ascribed to shallow donor bound exciton and possibly free to bound recombination. The two main transitions are assisted by optical phononmodes. Temperature-dependent PL measurements performed on these anatase crystals reveal that the donor bound exciton is stable below 90 K. Hydrogen trapped in oxygen vacancies is proposed to be the shallow donor. In addition, two activation processes are involved for the thermal quenching of donor bound excitons. The total activation energy is found to correlate well with the localisation energy of the bound exciton. Site-selective PL spectra obtained from anodic TiO2 tubes reveals that the luminescence of the nanostructures depends on the morphology. The result shows unusual near-band edge emission (NBE) for these structures, which is rarely observed in indirect band gap TiO2. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2023
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  • Date Issued: 2023-12

Effects of fire on architecture and composition of canopy shrubs in subtropical dune thicket of the southeastern Cape Floristic Region

  • Authors: Strydom, Tiaan , Grobler, Adriaan
  • Date: 2023-12
  • Subjects: Plant ecology -- Research , Plant communities -- South Africa , Browsing (Animal behavior)
  • Language: English
  • Type: Doctorial theses , text
  • Identifier: http://hdl.handle.net/10948/62632 , vital:72899
  • Description: Disturbance, such as fire and megaherbivory, is a pervasive phenomenon globally and has different effects on the flora and vegetation of different ecosystems. The Cape Floristic Region (CFR) of South Africa includes the distinctive Subtropical Thicket biome, which occurs as interrupted blocks that are not exposed to fire, but also as mosaics with the fire-prone vegetation of the Fynbos biome, especially on coastal dunes where thicket species are exposed to fire. Subtropical Dune Thicket (hereafter thicket) thus co-occurs with Fynbos, capable of supporting intense fires that can lead to thicket shrub defoliation and mortality. Thicket also experiences disturbance from meso- and megaherbivores that causes defoliation and mortality of shrubs. The aim of this study was to investigate the resilience of thicket shrub species to varying disturbance levels from fire and browsing to understand what drives thicket persistence in a fire-prone landscape. Firstly, I established the architectural traits of thicket species in long unburnt and post-fire contexts and investigated the relationships between these traits and the survival, resprouting ability and persistence of thicket shrubs. In mature thicket, I identified three distinct architectural guilds, namely hedge formers, lateral spreaders, and vertical growers. In post-fire thicket I identified three resprouting architectures, namely weak resprouters, moderate resprouters and strong resprouters. There was no strong relationship between the unburnt and post-fire resprouting architectures. Secondly, I compared thicket species and architectural composition in patches of landscape that experience different levels of fire exposure to assess the potential effect of fire frequency on determining thicket structure. I recognised three thicket vegetation units, each with a distinct structure and each corresponding to the level of fire exposure in the landscape. The first unit, forest-thicket, is exposed to low levels of fire frequency (> 100 years) and harbours forest species, many of which were vertical growers. The second unit, thicket, is exposed to moderate levels of fire frequency (50-100 years) and is dominated by lateral spreaders. The last unit, fynbos-thicket, is exposed to high levels of fire frequency (10-50 years) and here hedge-forming shrubs dominate the canopy cover. Forest-thicket and fynbos-thicket had a diverse set of shrub species with many being restricted to their respective vegetation type, whereas thicket had a lower diversity with no unique shrub species. , Thesis (DPhil) -- Faculty of Science, School of Natural Resource Management, 2023
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  • Date Issued: 2023-12

Effects of selected natural flavonoids on an optimized insulin resistance induction model on myotubes and hepatocytes in vitro

  • Authors: Van de Venter, Ruben
  • Date: 2023-12
  • Subjects: Flavonoid , Insulin resistance , Myotubes and hepatocytes
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/63049 , vital:73085
  • Description: Introduction: As the third largest life-threatening non-communicable disease, further research to improve T2DM treatment remains pivotal. The approved insulin sensitizing agents, metformin and thiazolidinediones, although effective, have an array of adverse effects. This leads to the growing need for safer insulin sensitizing agents. Aims: To induce insulin resistance, an insulin resistance induction (IRI) model consisting of palmitic acid (PA), fructose, and dexamethasone (DEX), was optimized. The model was utilized to compare the insulin sensitizing efficacy of chrysin, apigenin, luteolin, and quercetin. The most effective flavonoid was extrapolated based on the hydroxylation hypothesis and relevant SAR. The flavonoid was combined with metformin to evaluate potential insulin sensitizing synergism. Methods: C3A hepatocytes and L6 myotubes were exposed to the IRI models: IR1, IR2, and OIR, for 24 and 48h. Morphological features indicative of insulin resistance were monitored through high-content analysis (HCA). Thereafter, cells were exposed to OIR and concurrently treated with the selected flavonoids. Cytotoxicity, oxidative stress (OS), mitochondrial content, mitochondrial membrane potential (MMP), and lipid accumulation, were once again evaluated through HCA. Subsequently, quercetin was combined with metformin (QM); insulin resistant conditions established through OIR exposure, and QM administered as prophylaxis. The efficacy of QM was determined through changes in phosphorylated-Akt, glucose uptake, and gluconeogenesis. Results: IR1 and IR2 demonstrated excessive potency, whereas OIR consistently generated insulin resistant C3A/L6 cells by increasing OS (↑14%/20%), lipid accumulation (0.7-fold/1.5-fold), and decreasing MMP (↓4%/6%). Of the selected flavonoids, quercetin was most effective at ameliorating each of these parameters. Furthermore, QM demonstrated potential insulin sensitizing synergism, as it improved Akt phosphorylation (Thr308: ↑31%/↑17%; Ser473: ↑29%), glucose uptake (↑10%/ 5%), and suppressed hepatic gluconeogenesis (15↓%) more effectively compared to monotherapy. Conclusions: OIR is an effective model for the induction of complete early-stage insulin resistance in myotubes and hepatocytes. Quercetin demonstrates exceptional antidiabetic activity due its unique expression of hydroxyl groups. Lastly, QM, comparative to monotherapy, improves insulin sensitivity with enhanced efficacy. , Thesis (Ma) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Enhancing the optimal use of the properties for revenue generation at the National Department of Public Works and Infrastructure

  • Authors: Twala, Zolile Donald Linda
  • Date: 2023-12
  • Subjects: Buildings -- Maintenance and repair , Buildings -- Maintenance , Public works -- South Africa , Infrastructure (Economics) -- South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/66068 , vital:74329
  • Description: Literature on property management revealed that it became a challenge in many countries to manage and maintain properties, especially in the public sector. Concerning public infrastructure, research has confirmed that even in the most developed states, such as Canada and the United States of America (USA), the maintenance of public properties and related services was in danger due to fewer funds being budgeted for maintenance during their life cycle (Kaganova & Telgarsky, 2018). It was noted that there needed to be more studies conducted in South Africa under public infrastructure. This study aimed to explore how the NDPWI could improve the optimal use of properties under its custodianship to maximise revenue generation by carrying out the identified critical success factors from the property managers (internal) and client departments (external). Trying to find a well-maintained property creates more chances for the client departments or tenants to occupy the property for a more extended period while delivering their service to its clients and the NDPWI maximising the revenue generation. “The research applied a literature review and other sources, such as internal or media reports, as a background to discover meaning-making of insights from the property manager’s experiences, which were associated with their perceptions of property management challenges”. This research applied a qualitative research approach. Qualitative content was analysed, utilising a mixture of a deductive and inductive approach. The main reason for utilising both deductive and inductive approaches is that the researcher tried to understand and develop the theory around the NDPWI low-income generation utilising state properties to their optimal use and find out if all properties were well maintained and could, which allowed the NDPWI to maximise income generation. Five conclusions emerged from the findings of this study on insight from twenty-five (25) property managers who have been in their role for a minimum of five (5) years. The proof to substantiate these conclusions came directly from insights shared by the twenty-five (25) participants from their experience in property management. Conclusions were linked to the theories and reports that informed this study. Firstly, this study revealed that the majority of the participants agreed that the role of leadership in property management was critical for giving strategic direction within the organisation, ensuring that there were clearly defined roles and responsibilities, and ensuring there were no contradictions and confusion among the staff while executing their functions. Adequate talent was recruited, but skills were required to be strengthened. Secondly, the study revealed that the non-maintenance of state buildings contributed negatively to the client departments when executing their constitutional mandate efficiently and effectively in a safe environment. Poor building conditions were revealed as among the issues that the client departments needed to be occupying and optimally utilising; instead, they relied on leased inn properties from the private sector. Thirdly, the study revealed that the client relationship and quality of service they received from the NDPWI needed to be improved to ensure that clients were prioritised on their needs and expectations. NDPWI was taking too long to respond to the instruction of the client departments, and it was frustrating the client departments leading to some client departments proposing to devolve the power of the NDPWI to assist them. Fourthly, accessibility of the state properties was not as good as it was supposed to be, as the client departments would need the properties in specific areas, they needed to offer their services, and they could not get such properties under the NDPWI. They ended up looking for leased properties that meet their specification in the procurement instruction in good condition and safety. Fifthly, innovative technology could improve communication between the clients and help save time on conducting meetings in one common place. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2023
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  • Date Issued: 2023-12

Establishment of a high-content neurodegenerative disease model screening platform

  • Authors: Swanepoel, Bresler
  • Date: 2023-12
  • Subjects: Molecular neurobiology , Nervous system -- Diseases , Nervous system -- Degeneration
  • Language: English
  • Type: Doctorial theses , text
  • Identifier: http://hdl.handle.net/10948/62644 , vital:72906
  • Description: The identification of viable therapeutic targets and new treatments for central nervous system disorders, especially neurodegenerative diseases, remain major challenges in the field of drug discovery. Over the past few years there has been a steady decline in the turnaround time of current screening processes to yield viable drugs. Therefore, an increasing need exists for better technologies, protocols, and the screening of larger libraries. High-throughput screening provides the best solution to this problem and has become a key part in the drug discovery and development process. Likewise, high-content analysis has gained popularity over the past few years and is suitable for high-throughput screening. The aim of this study was to establish a comprehensive in vitro neuroprotective screening platform incorporating high throughput screening, using Parkinson’s disease as the neurodegenerative disease of interest. To evaluate the success of this platform, the neuroprotective potential of two mushrooms (Hericium erinaceus and Phlebopus sudanicus), two plants (Lippia javanica and Myrothamnus flabellifolia) and two seaweeds (Eucheuma denticulatum and Kappaphycus alvarezii) were investigated. Aqueous and ethanolic extracts of the selected natural products were evaluated across 21 parameters associated with four hallmarks of neurodegeneration: acquiring senescence, acquiring cell death, neuroinflammation and altered metabolism/cell survival. Based on the effects of these selected natural products on the 21 parameters, their potential mechanisms of action were elucidated. In addition to this, the natural products were scored under each of these therapeutic targets in an attempt to identify the most suitable animal models for future studies. The scoring system indicated that animal models investigating anti-senescence ability would be more suited for extracts of H. erinaceus, P. sudanicus and E. denticulatum whereas studies investigating the prevention of cell death would be more suited for extracts of E. denticulatum, L. javanica and K. alvarezii. Likewise, models based on neuroinflammation would be best suited for extracts of H. erinaceus, E. denticulatum and L. javanica while studies examining altered metabolism/cell survival would be best suited to extracts of H. erinaceus, E. denticulatum, K. alvarezii and M. flabellifolia. Considering the pleiotropic nature of the selected natural products, models that can combine these therapeutic targets could be of great interest. 6-OHDA proved to be capable of inducing favourable effects, in all the parameters investigated, with regard to a neurodegenerative state. However, it is known to have some disadvantages when it comes to pathological features such as the lack of the ability to induce Lewy body formation. Choosing the correct inducer remains a daunting task and no model, whether cell-based or animal-based, exists yet in which all the features of neurodegenerative diseases have been successfully replicated. The limitations of the current models, however, does not mean that they do not produce valuable insights. This is especially true if the mechanism of action for a specific compound or natural product is unknown. Animal models are still indispensable for the validation and interpretation of the results obtained from cell models with particular importance to toxicity. Therefore, this study assessed the best studied extract with the highest overall score for its toxicity using a zebrafish larvae-based model. Assessment of the toxicity of H. erinaceus revealed that both aqueous and ethanolic extracts resulted in death at the highest concentrations. This was supported by the results obtained in the in vitro cytotoxicity screening. In conclusion, this highlighted the importance of using physiologically relevant concentrations and supported the translational value of the current cell-based screening model to animal models and possibly humans. The findings of the present study suggest that a scoring system, which categorizes the different activities of selected natural products into distinct groups, can be a useful tool to improve the translatability of in vitro results to animal models. Furthermore, the current study arguably provides the most comprehensive neuroprotective screening platform in existence. Future research can look at expanding the platform through incorporation of additional parameters based on other hallmarks of neurodegeneration, not covered in this study, including protein folding and aggregation, altered epigenetics and the examination of other neuronal markers such as the involvement of astrocytes, oligodendrocytes, and microglia. In addition to this, future research can make use of more sophisticated cell models such as differentiated, human induced pluripotent stem cells and three-dimensional cultures. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2023
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  • Date Issued: 2023-12

Evaluating antidiabetic properties of selected African medicinal plants in a cell-based model

  • Authors: Sirkhotte, Saeedah , Reddy, Shanika
  • Date: 2023-12
  • Subjects: Medicinal plants -- South Africa , Insulin resistance , Gluconeogenesis
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/62600 , vital:72827
  • Description: The World Health Organisation lists diabetes as one of the major non-communicable diseases affecting the world, and its prevalence is expected to increase rapidly. Type II diabetes mellitus (T2DM) is characterised by insulin resistance and impaired blood glucose control. T2DM is of growing concern within South Africa, with 10.8% of the population currently diagnosed. The popularity, as well as availability, of traditional plant-based medicine in South Africa, might provide a solution. Antidiabetic potential is commonly tested by in vitro assays, however the methods to test this potential via gluconeogenesis are limited. This project aimed to optimise an in vitro hepatic gluconeogenesis model. In addition, this project aimed to determine the antidiabetic properties of Prunus africana, Hypoxis stellipilis, and Eriocephalus africanus by in vitro analysis. These properties were examined in human hepatoma cells (C3A cell line) and rat pancreatic cells (INS1 cell line) and methods included: cytotoxicity analysis, Amplex® red glucose oxidase assay, antibody staining, gene expression analysis by RT-qPCR, oxidative stress analysis, and calcium signaling for insulin release. Insulin resistance was successfully induced by exposing C3A hepatocarcinoma cells to a combination treatment of 50 μM dexamethasone, 1.25 mM fructose and 0.125 mM palmitic acid for a period of three days. Thereafter, gluconeogenesis was assessed using the Amplex® red glucose oxidase assay. The established model was effective in inducing insulin resistance and upregulating gluconeogenesis. Of the tested plant extracts, H. stellipilis showed the most potential as an antidiabetic treatment. It had low toxicity, significantly decreased hepatic glucose production and reduced the amount of phosphoenolpyruvate carboxykinase (PCK) and well as PCK gene expression, and reduced lipid content and reactive oxygen species (ROS) in the C3A cell line. H. stellipilis increased calcium signalling in INS1 rat insulinoma cells, however there was a decrease in expression of genes for insulin and glucose transporter 2 after 6 hr exposure. H. stellipilis appears be beneficial as an antidiabetic treatment. Although antidiabetic studies have been done on other Hypoxis species, this is the first study on the effects of H. stellipilis on gluconeogenesis and diabetes. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2023
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  • Date Issued: 2023-12

Evaluation of the antidiabetic potential, safety and efficacy of selected natural products using zebrafish larvae and in vitro bioassays

Evidence of Late Holocene extreme marine wave event (tsunami) deposits along the South African coast and implications for coastal zone management

  • Authors: Mfikili, Athi Nkosibonile
  • Date: 2023-12
  • Subjects: Tsunamis -- South Africa , Coasts -- Risk assessment , Sediments (Geology)
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/62517 , vital:72811
  • Description: Although extreme marine wave events such as tsunamis and storm surges have always been part of human existence, their impact on ever-growing coastal population of the world’s coast was highlighted by the recent catastrophic events over the past three decades. Although in situ observations and eyewitness accounts have improved our ability to record and interpret wave inundation by modern extreme marine events, records documenting inundation by pre-historic and historical events are relatively sparse to provide reasonable information on their distribution, magnitude and frequency intervals in most parts of the world. Owing to consequences these natural coastal hazards have on coastal population and infrastructure of the world’s coast, onshore sedimentary deposits preserved in the geological records have been extensively utilized by scientists worldwide to reconstruct the record of pre-historic and historical events and establish the recurrence interval of future events. Although studies investigating inundation of past tsunami has increased worldwide over the past two decades, research on extreme marine inundation has received little attention along the South African coast, despite known inundation by recent events and potential source mechanisms. Therefore, the aim of this study is to investigate sedimentary evidence of past tsunamis and related extreme marine wave events (i.e., storm surges) preserved in the recent geological archive of several coastal environments along the South African coast. The Swartkops, Kabeljous, Kromme and Keurbooms estuaries located in log-spiral bays along the south-east coast and sheltered coastal systems of the Berg Estuary and Verlorenvlei as well as coastal lowlands of the Dwarskersbos on the west coast were selected as the study sites. The sediment cores were collected from these coastal environments and identification of extreme marine wave inundation was based on the recognition of distinct anomalous sand layers. To characterise sediment transport and reconstruct provenance source origin of the deposits, a combination of sedimentological (i.e., grain size distribution), exoscopy (i.e., quartz grain surface microtextures) and micropaleontological (i.e., foraminiferal assemblages) proxies were utilized. Furthermore, age estimation of the deposits was determined using a combination of radiocarbon (14C) and radiometric (137Cs and 210Pb) dating methods.Evidence of coastal flooding by high-energy marine wave events is found preserved in the stratigraphic records of Swartkops and Kabeljous estuaries along the south-east coast and lowlands of Dwarskersbos on the west coast in the form of anomalous sand deposits (layers). The anomalous deposits of Swartkops and Kabeljous estuaries generally consist of gravel-sized shell fragments often with a sharp erosive contact suggesting deposition by a highly energetic marine wave event. Although the preservation varies between cores, a maximum of three anomalous sand depositional layers are preserved in the Swartkops whereas only a single layer in the Kabeljous Estuary with a basal layer of calcrete deposits. 210Pb and 14C dating, constrain the ages of the younger deposits (i.e., the uppermost layer) at Swartkops between 1770-1804 AD and 339-3 cal. BP (1611-1947 cal. AD), respectively. Although these ages span over a wide period, they are interpreted to represent evidence of one of the historical tsunamis generated in the subduction zones of the Indian Ocean e.g., 1762 AD and 1797 AD events generated by 8.8 and 8.0 Mw earthquakes in the Arakan and Sunda Subduction Zones, respectively. Furthermore, the deposits could also represent geological evidence of the 1833 Mentawai events whereas evidence of 1883 Krakatau tsunami is not disregarded, since this event reportedly inundated Algoa Bay. On the other hand, the 14C dating constrain the ages of the second anomalous deposits between 1526-1253 cal. BP (424-697 cal. AD), whereas the older anomalous deposits preserved in the deeper sections of the Swartkops cores as well as the backwater channel of the Kabeljous Estuary are constrained to have been deposited around 4000 cal. BP. Although there is no known locally documented extreme marine wave event during this period, these deposits are interpreted to represent late and mid-Holocene tsunamis associated with mega-thrust subduction zones of the Indian Ocean whereas local submarine landslide generated event are also not disregarded entirely. On the west coast, three anomalous deposits representing extreme marine wave inundation are preserved in the coastal lowlands of the Dwarskersbos. Although the general sedimentary features and thickness vary between the deposits, the first anomalous deposits in the uppermost section of the cores consist of medium sand with scattered shell fragments whereas, the third anomalous deposits in the deeper section of the cores are generally coarser with gravel-sized shell fragments and sharp erosive basal contacts. By contrast, the second anomalous deposits consist of three successive sub-layers of yellow sand with variable sedimentary features and these layers represent successive wave inundation events. Although the sedimentary characteristics of these sub-layers varies, it was noted that the lowermost layers consist of coarser and less well sorted sediments often with basal erosive contact, suggesting that the first wave was more energetic than the two-succeeding waves. Furthermore, calibrated 14C dated shell fragments from the first and second anomalous deposits yielded ‘post-bomb’ ages suggesting deposition after 1950 AD. Given their position within the stratigraphic records, the two deposits are interpreted to represent first geological evidence of the 2008 west coast and 1969 Dwarskersbos events, respectively. On the other hand, the 14C dated shell fragments constrain the deposition of the third anomalous deposits between 315-0 cal. BP (1635-11950 cal. AD) and 358-0 cal. BP (1592-1950 cal. AD), respectively. The third anomalous deposits are interpreted to the 07 April 1620 event, which was described as ‘Two startling thunderclaps’ near Robben Island. Although initially associated to earthquakes, there are no records of an earthquake during this period, therefore, we postulate that the 1620 event could have been a similar event to that of 2008 that inundated the west coast region and/or an unknown event. While it is acknowledged that the absence of reliable source mechanisms poses a great challenge in the reconstruction of extreme marine wave events inundation along the south-east coast, the findings of exoscopy and micropaleontological analyses suggest that the deposits were transported to their depositional environments, although resultant microtextural features and occurrence of individual foraminiferal species and their taphonomical conditions is dependent on coastal setting. The south-east coast deposits consist of highly diverse foraminiferal assemblages, which are dominated by marine and marginal-marine taxa with relatively low abundances of estuarine-brackish species and variable taphonomical conditions. Furthermore, the mechanical-induced features such as percussion marks, fresh surfaces with sharp edges were still preserved on quartz grain surface of the Swartkops deposits, despite dominance by chemical-induced features such as dissolution. By contrast, grain surface microtextural signatures of the Dwarskersbos deposits are dominated by mechanical features such as fresh surfaces and v-percussion marks. Furthermore, the foraminiferal assemblages of the Dwarskersbos deposits consist of exclusively marine and marginal-marine species, suggesting that the sediments were sourced from shallow water environments as well as the adjacent beach. It was further noted that the foraminiferal tests of these deposits consist of higher abundance of corroded and fragmented tests indicating deposition by high-energy conditions. , Thesis (D.Phil) -- Faculty of Science, School of Environmental Sciences, 2023
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  • Date Issued: 2023-12

Experiences of mothers who are on tuberculosis treatment While caring for their children in Nelson Mandela Bay health district

  • Authors: Mwadiwa, Chiedza
  • Date: 2023-12
  • Subjects: Caring experiences -- Nelson Mandela Bay , Tuberculosis treatment
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/62935 , vital:73071
  • Description: Women and mothers have an important role to play as caregivers of their children. However, mothers are often faced with challenges with fulfilling this important role. Many women value the caring role as a mother over other areas of their lives, and for ill women, such as those with tuberculosis (TB) and those on TB treatment, it can be difficult to relinquish maternal responsibility. Indeed, many mothers in South Africa and other low- and middle-income countries develop TB during pregnancy and postpartum because their immune systems are compromised. For a mother who is chronically ill, carrying out a mother’s caregiving role presents a range of challenges. However, few studies have addressed this problem or explored the experiences of such mothers. The purpose of the study was to understand the experiences of mothers who are on TB treatment while caring for their children in order to establish their support needs and thereby develop recommendations to assist CHWs, nurses and nurse managers at primary healthcare (PHC) clinics to provide optimum care to such women. The Socio-Ecological model was used as the theoretical lens to explore the phenomenon under investigation. A qualitative, exploratory-descriptive research design was identified as most suited to respond to the research question. Purposive sampling was used to select both the participants and the clinics in the Nelson Mandela Bay Health District (NMBHD) for the purpose of this study. The population was mothers on TB treatment caring for their children (aged five years or younger) who were attending either one of the two of the largest PHC clinics in Sub-district C in the NMBH. Altogether ten mothers on TB treatment caring for their children took part in individual semi-structured interviews conducted telephonically. Ethical clearance was obtained from Nelson Mandela University and permission was obtained from the Department of Health (DoH), district office, operational managers at the respective clinics, and the participants involved in the study. Trustworthiness was enhanced by ensuring credibility, transferability, dependability, and confirmability. Ethical principles were upheld throughout the course of this study namely respect for persons, beneficence and justice. All interviews were recorded and transcribed, and the data was analysed using Tesch’s method of data analysis to identify the themes. Three themes came out of the data, namely: Theme 1: Mothers expressed having to navigate a range of physical and psychosocial challenges while caring for their v children; Theme 2: Mothers struggled to perform motherly roles while on TB treatment; Theme 3: Mothers described their relationships with their family, community members and clinic health practitioners. The experiences of the participants were described using direct quotations from the interviews followed by a literature control used to verify the participants’ experiences. Thereafter, the findings were used to develop recommendations to optimise the care and support of mothers on TB treatment who are caring for their children. Four recommendations were developed: Recommendation 1: Prepare and support mothers with TB to care for themselves and their children; Recommendation 2: Assist CHWs and nurses to care and support mothers with TB and their children; Recommendation 3: Prepare and support family members to support mothers with TB and their children and Recommendation 4: Educate community members regarding the needs of mothers with TB. There is limited existing research on mothers who are on TB treatment while caring for their children. This research study helped to fill this gap, particularly in an urban Eastern Cape context. The findings illustrated mothers’ physical and psychosocial challenges, as well their role-related challenges and finally the challenges related to the various spousal, family, community and clinic relationships that influence their experience of caring for their child while on TB treatment. , Thesis (MA) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Experiences of psychological practitioners when working with Isixhosa speaking minors in the Eastern Cape.

  • Authors: Matushe, Masakhane
  • Date: 2023-12
  • Subjects: language barriers -- Eastern Cape , Psychological practitioner
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/62884 , vital:73062
  • Description: Language barriers continue to pose challenges in education and the health sector where psychological assessments and tests are administered in a language that is different from that of the client. The implication this has on the interpretations of test-taker scores may be bias against those whose first language is not English or Afrikaans, which are two of the primary languages majority of the tests currently used in the South Africa are normed against. This study aimed to explore the implications of the current language repertoires on test-taker performance. This was achieved through exploring the experiences of psychological practitioners who use English language psychological tests on isiXhosa speaking child clients in the Eastern Cape. The methodology followed an exploratory-descriptive, qualitative design, adopting Lincoln and Guba's model of trustworthiness. The researcher employed a qualitative method with an exploratory-descriptive research design, and participants were recruited by utilizing a purposive sampling strategy. Thematic analysis was used as a means of data analysis,and the following themes emerged and were discussed: The use of translators & interpreters, and the challenges thereof; practitioner’s own language proficiencies and limitations; cultutral influence and langaage exposure of clients; Adaptation as well as revision of decolonization of testing measures; and training psychological practitioners. , Thesis (Ma) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Exploring culturally adapted psychological interventions for mental illness in South Africa: A scoping review

  • Authors: Mbatha, Andiswa
  • Date: 2023-12
  • Subjects: Cultural Adaptation , Evidence-Based Treatments
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/62898 , vital:73065
  • Description: Culturally appropriate interventions are crucial for its universal applicability. Although it is well documented that mental health practitioners need to consider cultural factors when working with clients, there is a paucity of research concerning culturally adapted psychological treatments within South Africa. Mental Health practitioners use borrowed Westernised methods of psychological interventions, whose effectiveness has been proven to work on people with different values and belief systems from those of South Africa. This study sought to map the literature on culturally adapted psychological interventions in the South African context. The main research question of the study is: “According to the literature, what are the culturally adapted psychological interventions available for use in the South African context?” Employing the scoping review methodology, published literature was sourced from various electronic databases. The data is presented in a table format using the thematic framework. The study found that out of 250 records that were retrieved, we identified nine articles describing four distinct interventions in treating three mental illnesses in South Africa. Cognitive behaviour therapy (n = 3), behaviour activation (n=2) mindfulness-based stress reduction (n=2) interpersonal therapy (n=1) and Motivational interviewing (n=1) surfaced as culturally adapted psychological interventions to treat people with depression, trauma and substance use disorder. Improvement in symptoms was a common result of all therapies. The potential benefit of the study is to provide recommendations that will inform further research and clinical practice. , Thesis (Ma) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Exploring the leadership agility in industry 4.0 for company x in Gqeberha

  • Authors: Cairncross, Merle Vera
  • Date: 2023-12
  • Subjects: Leadership -- South Africa , Industry 4.0 , Business intelligence
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/65577 , vital:74193
  • Description: In today’s dynamic business landscape, more organisations are progressively attempting to become agile by implementing agile corporate structures, processes and leadership frameworks. By effectively incorporating leadership agility into their processes, leadership can be better prepared to improve its decision-making agility, further able to deploy strategies for improved detection and response to failure as well as improve communication in the organisation. This treatise explores the critical role of leadership agility in enabling organisations to navigate the challenges of a rapidly evolving environment such as Industry 4.0 and capitalise on emerging opportunities. For this study, qualitative data was collected from functional level management by means of semi-structured, face-to-face interviews. The interviews aimed to identify behaviours and beliefs that contribute to an agile organisation, examine barriers impeding agile decision-making and explore strategies to cultivate an agile decision-making culture. By understanding the key factors that enable leadership agility and promote agility within decision-making processes, this research aimed to provide valuable insights for organisations seeking to thrive in the dynamic landscape of Industry 4.0. Through literature analysis and interviews, the researcher concluded that agile leaders possess crucial competencies and behaviours that allow them to effectively navigate the challenges and opportunities of Industry 4.0. These include effective communication, openness to change, innovative thinking, flexibility, self-management, developing others and organisational awareness. Agile leaders strategize and prepare their organisations in Industry 4.0 by adopting an adaptive leadership style, cultivating an agile decision-making culture, encouraging continuous improvement, promoting creativity and innovation and responding swiftly to changes, thus gaining a competitive edge in Industry 4.0. Embracing leadership agility enables organisations to capitalise on Industry 4.0’s opportunities and navigate its challenges, ultimately fostering a competitive business environment. By organising and synthesising the knowledge obtained in this study, a framework is proposed for agile leadership, which consolidates , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School , 2023
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  • Date Issued: 2023-12

Exploring the psychological and emotional understanding of Amagqirha within the Eastern Cape province, South Africa

  • Authors: Ncapayi, Abongile
  • Date: 2023-12
  • Subjects: traditional healers , Indigenous Knowledge , Cultural religion
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/62947 , vital:73074
  • Description: Indigenous knowledge systems influence mental health understanding and treatments. Amongst the Xhosa’s (amaXhosa), a person may receive a ‘calling’ from the ancestors, usually associated with symptoms that would be characterized as a mental illness. However, the symptoms experienced during the calling, usually dissipate once training has been received. One of the categories within traditional healers are amagqirha, also known as diviners. These are individuals who receive the ‘calling’. Thereafter, they undergo extensive training and become blessed with clairvoyant “powers” to divine and act as mediators between the living and the dead. This study aimed to explore the psychological and emotional understanding of amagqirha of the Xhosa culture, within the Eastern Cape, South Africa. In doing so, the study centralizes the experiences of individuals within cultural spaces, allowing for commentary on the psychological and emotional understanding of the amagqirha. Furthermore, this study focused on the work that amagqirha do in communities and how this ultimately affects them. This study sought to understand the experiences and perceptions of the individuals who are affected by this ‘calling’. The researcher employed a qualitative method with an exploratory-descriptive research design. Ten participants were recruited by utilizing a purposive snowball sampling strategy. Data was collected using a semi-structured interview due to the sensitivity of the demographic of the study. Ethics were adhered to. Additionally, trustworthiness was guided by Lincoln and Guba’s (1985) four constructs: credibility, dependability, transferability, and confirmability. Thematic analysis was used as a means of data analysis, as presented by Braun and Clarke (2006). The themes identified were: The collateral damage/profuse repercussions cast upon by the ancestors due to inaction (either by them or those that case before them), the severity of the emotional and psychological effects is equally prevalent prior and during their journey of vi ubugqirha, methods that may assist in alleviating the emotional and psychological symptoms, understanding of mental health, awareness of their own mental health status, and help-seeking (psychological services). The main findings suggested that there is a general understanding of the term ‘mental health’ amongst amagqirha. Additionally, the findings revealed that amagqirha experienced emotional and psychological symptoms/effects, prior to and during the journey of ubugqirha - these were due to the lack of understanding and fear. Furthermore, the findings suggesting that amagqirha embarked on various help-seeking measures, i.e., seeking psychological services or leaning into seeking guidance from their ancestors. However, they were met with barriers as well, i.e., finding a mental health practitioner with awareness on African spirituality, and dealing with the stigma that comes with help-seeking. , Thesis (Ma) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Exploring the role of livelihood diversification of household food security in Umzimvubu Local Municipality

  • Authors: Tikilili, Noluthando
  • Date: 2023-12
  • Subjects: Food security -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Food industry and trade -- South Africa -- Eastern Cape
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/66054 , vital:74324
  • Description: The study sought to explore the role of livelihood diversification for household food security in rural communities of Umzimvubu Local Municipality for sustainable development. The study adopted an interpretive paradigm as it gave the researcher appropriate information from a group of participants who better understand the livelihood assets. The qualitative research approach was adopted for the study due to its ability to appreciate the opinions, feelings and experiences of distinct individuals in order to give meaning to their behaviours. To gain better inferences and insights into this phenomenon, the researcher used semi-structured interviews with smallholder farmers who depend on practising farm activities for their livelihoods. The findings of the study revealed that due to retrenchment and the increase in unemployment rate, families are experiencing income inadequacy that has urged rural households to engage mostly in on-farm activities as a way of generating income and supplementing their livelihoods to sustain their families. Additionally, the findings unveiled that the efforts by government as well as non-government stakeholders to mitigate the effects of poverty by introducing the local entrepreneurs to the formal market, were evident. However, there are no consistent and stable programmes and policies to extend the market, or to encourage commercial farmers and smallholder farmers to work together to improve rural economies and transfer the much-needed skills to subsistence farmers. The study recommends that the government should play a leading role in capacitating rural communities and adequate funding should be made available to execute off-farm and non-farm activities to tackle the issues of food security and eliminating poverty. Also, with the emergence of a changing climate, there is a need for the Eastern Cape government to erect irrigation schemes, which can be done to sustain on-farm production and productivity for the rural communities. There is a need for the government to facilitate the introduction of stable and consistent programmes and efficient and effective policies which will enforce the commercial and small-holder farmers to work together and ensure that the much-needed skills and expertise are transferred to the marginalised group whilst improving the rural economy and meeting the market demands. , Thesis (MA) -- Faculty of Business and Economic Sciences, School of Economics, Development and Tourism, 2023
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  • Date Issued: 2023-12

Exploring university level admissions decision-making based on access testing and undergraduate admissions variables

  • Authors: Oakes, Elizabeth
  • Date: 2023-12
  • Subjects: decision-making , Social-Judgement Theory , Cognitive-Continuum TheoryLens Model Equation
  • Language: English
  • Type: Doctoral's theses , text
  • Identifier: http://hdl.handle.net/10948/62969 , vital:73078
  • Description: Decision-making is an essential everyday cognitive function. How people go about making judgements and decisions is difficult to pin down. The reason for this lies in the inherent nature of decision-making, which is uncertain and variable because decision-making is a human cognitive process that is context-dependent. However, the body of research on judgement and decision-making (JDM) is concerned with describing what people are 'actually' thinking, when they make decisions or judgements. This study applied the descriptive theories of the Social-Judgement Theory (SJT) and the Cognitive-Continuum Theory (CCT), in order to understand decision-making in an undergraduate, entry-level admission decision-making context, in which decision-makers used access testing and school results, to make admission decisions at Nelson Mandela University. The sample consisted of four consultants from the Centre for Access Assessment and Research (CAAR) who volunteered to participate in the study. While the sample was small, it was nonetheless deemed to be adequate as 57% of the consultants at CAAR were included in the sample. Using the SJT methodological approach, an experiment was conducted to mirror the real-life context of decision-making at CAAR. As CAAR consultants were used to test, and school results being presented on a profile when they made decisions, a sample of 120 of these was drawn from a repository, with 60 of them requiring decisions for degree admission (to B Com Accounting) and 60 for diploma admission (to the Diploma in Accountancy). Ten degree and 10 diploma profiles were duplicated to check for consistency in decision-making. As SJT suggests restricting the number of cues used, a process was instituted to identify the cues perceived to be used most frequently to make decisions at CAAR. This resulted in 5 cues being included on the cue profile. In Phase 1 of the experiment the CAAR consultants made admission decisions using a familiar cue profile in terms of how the information was presented visually and numerically. In phase 2 the information was presented using a different visual format, which was more closely aligned to the intuitive decision-making mode that most consultants used. A 2 x 2 within-subjects experimental design was thus employed with two independent variables, namely, profile type and program type. Descriptive statistics and correlational and regression analyses were used to describe the judgement policies of the consultants in terms of the time taken, the difficulty ratings, and the cue use and its importance). The indices of the Lens Model Equation (LME) of SJT were used to describe the decision-achievement levels, and the Task-Continuum Index (TCI) was computed to describe which cognitive modes were used. xvii The results revealed that decision-makers have unique, varied, and changeable judgement policies, with regard to the time taken, the perception of difficulty, and the decision outcomes and had a tendency to rely more on the school results, while the regression models derived indicated that test results made a stronger contribution to the decision outcome. The consultants found degree decisions easier than diploma decisions, and the consultants perceived the contribution and weighting of the cues somewhat differently, once the format of the cue profile had changed in Phase 2, although they made decisions more quickly in Phase 2. The decision-makers also displayed individualised patterns of decision achievement that differed for degree and diploma programs. Furthermore, in terms of the cognitive mode, decision-makers were thinking quasi-rationally and they largely used the cognitive modes of computer modelling or expert judgement. Thus, by synergistically using the two theories of JDM, the researcher was able to determine baseline information for understanding decision- making in an admission context. Furthermore, suggestions were made in terms of the nature of the feedback and training that could be provided to decision-makers to enhance their future decision-making. Suggestions were also made regarding how the methodology used and findings of this study could be applied in other contexts, such as when training students in psychological assessment. , Thesis (Ma) -- Faculty of Health Science, 2023
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  • Date Issued: 2023-12

Factors contributing to operational excellence in a pharmaceutical manufacturer in East London, South Africa

  • Authors: Monakali, Xolani
  • Date: 2023-12
  • Subjects: Organizational effectiveness , Performance , Production management , Industrial management Pharmaceutical industry -- South Africa -- East London
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/65795 , vital:74268
  • Description: To ensure that high quality, secure and effective pharmaceutical goods are consistently produced and supplied to the appropriate end user, pharmaceutical manufacturing companies operate in a highly regulated environment. The idea that quality is not assessed is incorrect; rather, it is built, is at the heart of this production environment. Since fulfilling deadlines on time in full is the benchmark for good customer service, to achieve this results in numerous quality limits that have an impact on the quick delivery of medicines. Companies are often competing for the same clients; thus, there is increasing competition, which is mostly due to the availability of reasonable and inexpensive generics. The most profitable company will be the one which operates and produces at low cost, with great efficiency and economies of scale. Furthermore, the generic pharmaceutical firm is not immune from the fundamental purpose of business, which is to make money for the shareholders and add value for the clients. In order to maintain competitiveness in a pharmaceutical company which operates in East London, South Africa, this study aims to identify the factors that lead to perceived operational excellence. Respondents were given a standardised questionnaire; thus the study employed a quantitative research methodology. The sample size for the study was determined by randomly selecting 100 employees, composed of Operators, General Assistants, Production Team Leaders, Production Pharmacists, Pharmacist Assistants and Artisans from Pharmaceutical Company X. With the aid of a research assistant, the questionnaire was distributed to and answered by respondents. The gathered data were analysed using the Statistical Package for Social Sciences (SPSS) version 27 for Windows. The results of the study were then shown in cross tabulations, pie charts and bar graphs. The main outcomes of the study revealed that the majority of consumers believed pharmaceutical products were of a high calibre in terms of quality. Furthermore, the majority of participants agreed that operational excellence is important in companies that produce fast-moving consumer goods, like the pharmaceutical industry does. The survey also revealed the need for operational excellence in the pharmaceutical industry. Given that quality in the pharmaceutical industry has grown to be a crucial issue, the study suggests that the importance of pharmaceutical product quality needs to be more widely understood. Academics, pharmaceutical companies and legislators will all benefit from the study. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2023
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  • Date Issued: 2023-12
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