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Analysing the equity dimensions and governance drivers of water security challenges in Hammanskraal, City of Tshwane, South Africa
Get PDFSouth Africa is faced with a national water security challenge that is increasingly worsening due to a myriad of structural and governance factors. Over the past few years, several municipalities across the country have experience temporary loss of water access, while some have come dangerously close to Day Zero – a day when water levels of the major dams supplying water to residents would become critically low, resulting in households having no running water. But for the people of the township of Hammanskraal in the City of Tshwane metropolitan municipality, water insecurity has reached crisis point. Since 2005, the township has been battling with a chronic lack of access to safe drinking water. The water quality in Hammanskraal has been so dire that in 2019, the South African Human Rights Commission declared it unfit for human consumption and deemed it a violation of human rights. Despite this, the crisis has persisted. In 2023, Hammanskraal became the epicentre of a cholera outbreak that claimed a number of lives in several provinces across the country. Using a qualitative approach, this study analyses the equity dimensions and governance drivers of water security challenges in Hammanskraal. Through interviews with residents in Hammanskraal and government officials in the City of Tshwane metropolitan municipality and the Gauteng Provincial Government, the study explores the lived experiences of those affected by the water insecurity, as well as the governance drivers that inform the crisis. The study, using water justice theory and conflict theory/Marxism, contends that the water security challenges in Hammanskraal are driven by physical, economic and political factors. These factors have their roots in the geo-history of the township as well as contemporary responses to spatial development and water resource management by the post-apartheid government. The study finds that there are equity dimensions to the water security challenges in Hammanskraal. Contextually, the legacy of apartheid’s policy of separate and uneven development, coupled with contemporary failings of the implementation of the National Water Act, impact water access. In terms of water governance, while factors such as climate change and urbanisation are contributing determinants, the water security challenges in Hammanskraal are fundamentally the result of institutional failings that include lack of planning and investment as well as lack of infrastructure maintenance. The implications for South Africa in general is that failure to resolve water inequities and to strengthen water governance will result in the reproduction and persistence of structural inequalities. Key recommendations of the study include the expansion of the Temba Water Purification Plant, strengthening and coordination of institutions for water security, the setting of water allocation ceilings in Gauteng municipalities and investment in alternative water sources and tools for water conservation. The study also recommends further study into the extent to which water security challenges impact social unrest in South Africa.Thesis (MSc) -- Faculty of Science, Institute for Water Research, 202
Modelling water quality dynamics by integrating PYWR, climate change, and land-cover scenarios: a case study in the Grootdraai Dam Catchment, Upper Vaal, South Africa
Get PDFWater resource management faces global challenges in allocation, quality, and sustainability. Despite extensive focus on quantity, water quality remains neglected, especially in developing nations, owing to data scarcity and funding issues. Water quantity modelling is more advanced, leaving water quality modelling lagging, as it requires finer spatiotemporal scales. Global water quality models, including those used in South Africa, encounter complexity and data requirements, and some proprietary models limit access. In South Africa, a water quality model is integrated with the less accessible Water Resources Yield Model (WRYM). However, WRYM's spatial lumping may not suffice for water quality assessment, emphasising the need for improvement. This study aims to address the gap in water quality modelling by transitioning from lumped, proprietary, and monthly time-step models applied in South Africa to more spatially distributed, user-friendly, transparent, fast models and daily time-step models, using the Grootdraai Dam Catchment in the Upper Vaal as a study region. The study examines providing water quality simulation for various variables under different tested scenarios, including (i) land-use scenarios (e.g., urbanisation, industrialisation, population growth and expansion in agricultural areas); (ii) mixed scenarios (e.g., climate change, mine closure, and demand increase). The study proposed a framework shifting from the WRYM to a Python water resources (Pywr) model, linked with the Water Quality Systems Assessment Model (WQSAM) in the Grootdraai Dam Catchment. This integration, the Python water resources-Water Quality (Pywr-WQ) model, was developed by the Water Research centre (WRc) in the United Kingdom. The study employed multiple regression models to develop land-use models, the outcomes of which were integrated into the Pywr-WQ model for medium and long term land-use scenario predictions. The study resulted in the following findings: (1) significant patterns emerge concerning the impacts of urbanisation, mining, and agricultural expansion on water quality; (2) urban areas exhibit elevated levels of nitrate plus nitrite and ammonium over the long term associated with human activities and infrastructure development; (3) increased cultivation leads to heightened phosphate levels, indicative of agricultural runoff and potential high fertiliser usage, while the expansion of mining activities results in elevated concentrations of sulphate and Total Dissolved Solids (TDS), attributed to the discharge of mine effluents; (4) noticeable declines in the concentrations of TDS and sulphate are evident in the medium to long term when compared to the baseline simulations. However, the worst-case scenario (i.e., a 70% abstraction increase) exhibits elevated peaks and concentrations compared to scenarios with more probable demand increases (e.g., a 5% increase).Thesis (MSc) -- Faculty of Science, Institute for Water Research, 202
Fluorescence-doped silica nanoparticles for ultrasensitive detection of prostate specific antigen
Get PDFProstate cancer (PCa) is the topmost diagnosed cancer in males in South Africa according to the National Cancer Registry 2020, affecting both adolescent and young adult men. Currently, PCa is diagnosed using the dreaded digital rectal examination (DRE) followed by tissue biopsy, and prostate-specific antigen (PSA) test for confirmation. DRE is an invasive method and can detect PCa in late stages when the tumour has formed. Therefore, there is a need for early diagnosis technology, that can detect PCa during carcinogenesis. PSA test offers this opportunity even though it is non-specific. This test is a non-invasive, well-established, and conventional method used as a confirmatory test. However, the test suffers from shortfalls like the misdiagnosis of benign prostatic hyperplasia (BPH) or prostatitis as prostate cancer. In this work, we have developed an ultrasensitive fluorescence-based PSA test based on the oriented immobilization of anti-PSA monoclonal and polyclonal antibodies. Anti-PSA polyclonal antibodies (anti-PSA-pAb) were bioconjugated via boronate ester onto the fluorescein-5-isothiocyanate (FITC) doped silica nanoparticles for detection. Anti-PSA monoclonal antibodies were used as capture antibodies on dark fluorescence microplate or magnetic nanoparticles. A sandwich immunoassay was used for the detection of PSA. The anti-PSA-pAb was bioconjugated on the surface of the FITC-doped silica nanoparticles. In the design, the FITC-(3-aminopropyl)triethoxysilane (APTES) organosilane precursor was encapsulated into the silica nanoparticles to form fluorescent silica nanoparticles (FITC@SiO2NPs). The silica shell prevented dye leakage and promoted fluorescent signal amplification. Optimization of the as-prepared fluorescent silica nanoparticles was investigated at altered FITC-dye loadings of 3.0% and 6.0% (for high loading). The fluorescent silica nanobioconjugates exhibited a strong excitation-dependent emission property at 518 nm and was photostable over time. The fluorescent silica nanoparticles exhibited 65% dye loading for both 3.0% and 6.0% silica nanoparticles respectively for 30 ± 3 nm and 46 ± 2 nm. The fluorescent nanobioconjugates’ performance was evaluated using black 96-well microplates. A fluorescence sandwich-type immunoreaction was achieved via the antibody-antigen reaction of the FITC@SiO2-prAmPBA-anti-PSA-pAb/glucose nanobioconjugates binding to the captured PSA analyte. NaOH was used for alkali hydrolysis of the sensing nanobioconjugates to release the FITC-APTES molecules, leading to fluorescence signal amplification. The proposed fluorescence immunobiosensor exhibited a linear relationship between the fluorescent signals and the concentration of PSA obtained in the range of 2.0 pg.mL-1 to 50 ng.mL-1, with excellent limit of detection and limit of quantification both in the pg.mL-1 range in PBS buffer (pH 7.4) and PSA in spiked serum samples. The immunosensor was based on the immunometric sandwich protocol, using nanomagnetic-silica antibody bioconjugates for capture and fluorescent nanobioconjugates as sensing probes. The use of nanomagnetic-silica antibody bioconjugates allowed concentration of PSA as the analyte and ease of separation using a magnet. Alkali hydrolysis of the sensing fluorescent nanobioconjugates is achieved using NaOH, resulting in the release of FITC molecules and an amplified fluorescence detection signal. The analytical performance of the proposed fluorescence immunobiosensor exhibited a linear relationship between the fluorescent signals and the concentration of PSA obtained in the range of 2.0 pg.mL-1 to 100 ng.mL-1, with excellent limit of detection and limit of quantification both in the pg.mL-1 range in PBS buffer (pH 7.4) and PSA in spiked serum samples. The immunosensor also exhibited good specificity and selectivity for PSA with 94.8% - 102.5% recovery rates. The proposed fluorescence immunoassay exhibited high selectivity and specificity for the detection of PSA.Thesis (MSc) -- Faculty of Science, Chemistry, 202
Co-crystal formation of pharmaceutical and veterinary tranquilizer molecules
Get PDFMidazolam, a 1,4-benzodiazepine derivative is commonly used to treat anxiety, insomnia and may be used as a sedative in anaesthesia as it has calming, anti-convulsant and muscle relaxant properties. Midazolam has a rapid onset but a short duration of action resulting in fewer adverse effects. Midazolam also has the potential to form insoluble crystalline precipitates in pharmaceutical dosage forms such as syrups and solutions, which is a challenge in formulation and process development activities. The primary goal of this research was to prepare multicomponent crystals of midazolam free base, specifically targeting interactions with coformers structurally similar to methyl paraben. Key preparation techniques included neat grinding, liquid-assisted grinding, and slow evaporation. The resulting solid forms were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and powder X-Ray Diffraction (PXRD). In addition, Single-Crystal X-Ray Diffraction (SCXRD) was used to elucidate detailed structural information on the novel multicomponent crystals formed. Successful preparation of midazolam free base from the hydrochloride salt was confirmed through FTIR, DSC, and PXRD analysis. Different co-crystals and salts of midazolam with coformers such as salicylic acid (SA), benzoic acid (BA), 3-hydroxybenzoic acid (3-HBA) and p-aminobenzoic acid (PABA) were synthesized and characterized. The structure of the single crystal obtained from a veterinary tranquilizer solution was solved and found to be a salt that had formed between midazolam free base, midazolam HCl, and methyl paraben. This finding inspired further investigation of similar multicomponent crystals of midazolam and methyl paraben analogues. This study demonstrated the effectiveness of both mechanochemical and slow evaporation methods for the preparation of multicomponent crystals. PXRD and DSC provided insights into the stability and purity of the crystals that had formed and the differences in melting points and PXRD patterns were particularly important in this regard. Differences in FTIR spectra were used to distinguish between different solid forms and to confirm the successful formation of new solid forms. Extensive searches in the Cambridge Structural Database (CSD) confirmed that the multicomponent crystals of midazolam, such as MDZ‧SA, MDZ‧BA, MDZ‧3-HBA, and MDZ‧PABA, had not previously been reported, highlighting the novelty of these findings. The research successfully isolated and characterized several novel multicomponent crystals of midazolam, demonstrating the potential of mechanochemistry and solvent evaporation techniques in the development of pharmaceutical and veterinary medicinal applications. These findings contribute to the understanding of cocrystal formation and provide a foundation for future studies in which the stability and efficacy of midazolam-based formulations can be evaluated.Thesis (MSc) -- Faculty of Science, Chemistry, 202
Do the Cytochrome P450 1A2 allele variations have an effect on the structure and function of the protein?
No full textAccess restricted. Expected release in 2025.Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 202
Teacher professional development as a mechanism to advance education for sustainable development (ESD) integration in Namibia: a senior primary English language case study
Get PDFNamibia is a signatory to the Sustainable Development Goals of Agenda 2030 and responds to the United Nations Decade of Education for Sustainable Development by incorporating Education for Sustainable Development (ESD) into its education curriculum and policies. In 2020, Namibia launched its National Environmental Education and Education for Sustainable Development Policy. Despite these policy commitments, research indicates that most teachers continue to struggle with integrating ESD into their teaching practices. The integration of ESD in English language teaching classrooms is no exception. This qualitative case study is an attempt to understand how a Teacher Professional Development programme named Teach for ESD offered by NaDEET, a non-governmental organisation in Namibia, aided three Senior Primary Phase English Language teachers to integrate ESD into their teaching practice. The study also aims to unveil the teaching practice of the selected English Language teachers in the Otjozondjupa region who participated in the Teach for ESD programme. Data was gathered using semi-structured interviews (three interviews per teacher), document review, and lesson observation (one per teacher). Theoretically, the study is framed by socio-cultural learning theory after the work of Lev Vygotsky, supplemented by Mavhunga and Rollnick’s (2013) account of Topic Specific Pedagogical Content Knowledge (TSPCK). The qualitative data was analysed inductively to identify themes and sub-themes relevant to the research questions. The study findings might be of value to NaDEET as they implement future TPD courses in ESD, and they may also be of interest to English Language Teaching stakeholders as Namibia implements the EE and ESD Policy in the national school curriculum. The findings showed that the English Language teachers need ESD training; ESD-oriented teaching and learning materials; continuing support for monitoring and evaluation of their ESD practices; and more time allocated to English Language teaching in the timetable so that the environmental / sustainability content can be explored in more depth alongside the development of English Language skills. The study recommends that further research be conducted into effective ways of teaching English Language skills through environmental themes (developing Pedagogical Content Knowledge); and exploring up-scalable models of teacher professional development so that more English Language teachers can receive ESD training.Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 202
The relationship between financial sector deepening and income inequality in South Africa
Get PDFThis research analyzes the relationship between financial sector deepening and income inequality in South Africa from 1980 to 2019, using data from the World Bank Database and the Standardized World Income Inequality Database. An autoregressive distributed lag (ARDL) model is used to explore both the long- and short-run relationships that exist between these variables. Additionally, control variables like GDP, inflation, and structural changes that occurred, which include 1994 and 2005 are considered. According to the findings, the financial sector exacerbates income inequality in the long run. These findings highlight the need for policymakers to prioritize inclusive financial sector reforms. One recommendation is to enhance the access of Small, Medium, and Micro Enterprises (SMMEs) to formal financial services. For example, promoting more black industrialists and SMMEs in the supply of financial products and services. Possible reforms may include adjusting credit requirements for different income groups or offering lower interest rates on loans for businesses. Ensuring that more financial sector gains are retained within black communities can foster inclusive growth by generating jobs and ensuring a more equitable distribution of income.Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 202
Drug development and animal welfare: bioethical analysis of emergency situations and the research settings
No full textAccess restricited. Expected release date 2026.Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 202
MeerKAT observations of the Abell 141 galaxy cluster
Get PDFThis study is aimed at being an overview and investigation of the behaviour and morphology of radio quiet (RQ) active galactic nuclei (AGN) in the radio and optical/near-infrared (NIR) bands. It is hoped that a concise description of the relation that exists between accretion activity and star formation (SF) will be achieved through utilization of multiwavelength astronomy analysis. This analysis includes the processing of data acquired from the MeerKAT International GHz Tiered Extragalactic Exploration survey (MIGHTEE), the Southern African Large Telescope (SALT), the Hyper Suprime Camera (HSC) mounted on the Subaru telescope and the VISTA telescope. In this thesis, several targets were observed using SALT spectroscopy, but a redshift of only one of them was obtained. Lastly, it was established that for the sample of RQ AGN studied, the AGN contribute a large fraction of the radio emission observed.Thesis (MSc) -- Faculty of Science, Physics and Electronics, 202
A MIGHTEE Investigation of radio quiet AGN
Get PDFThis study is aimed at being an overview and investigation of the behaviour and morphology of radio quiet (RQ) active galactic nuclei (AGN) in the radio and optical/near-infrared (NIR) bands. It is hoped that a concise description of the relation that exists between accretion activity and star formation (SF) will be achieved through utilization of multiwavelength astronomy analysis. This analysis includes the processing of data acquired from the MeerKAT International GHz Tiered Extragalactic Exploration survey (MIGHTEE), the Southern African Large Telescope (SALT), the Hyper Suprime Camera (HSC) mounted on the Subaru telescope and the VISTA telescope. In this thesis, several targets were observed using SALT spectroscopy, but a redshift of only one of them was obtained. Lastly, it was established that for the sample of RQ AGN studied, the AGN contribute a large fraction of the radio emission observed.Thesis (MSc) -- Faculty of Science, Physics and Electronics, 202