Metallophthalocyanines: versatile probes for microbial photoinactivation and for pollutant degradation as photocatalysts, both molecular or supported form
- Authors: Sindelo, Azole
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466614 , vital:76760 , DOI https://doi.org/10.21504/10962/466614
- Description: This thesis investigates the synthesie of metallophthalocyanines for potential use as photosensitizers in two applications: photodynamic antimicrobial chemotherapy and the photodegradation of organic pollutants. To achieve this, phthalocyanines with morpholine (substituted at alpha and beta position, to imine), ethyl and propyl pyrrolidine Schiff bases, asymmetrical mercaptobenzothiazole and morpholine substituents were synthesized for the first time. All nitrogen containing phthalocyanines were methylated to form cationic derivatives. Asymmetrical mercaptobenzothiazole were covalently linked to spherical and pyramidal zinc oxide nanoparticles, while the asymmetrical morpholine were conjugated to polyacrylonitrile (PAN) nanofibers, chitosan modified PAN and glass wool, while carboxylic acid containing phthalocyanines were also linked to glass wool. Various characterization techniques, including electronic spectroscopy, mass spectroscopy, nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR), elemental analysis, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscope (SEM), and time-resolved fluorescence measurements were employed to characterize all the phthalocyanine composites. The research aimed to establish general trends in fluorescence quantum yields, triplet and singlet oxygen generation, photodegradation rates, and fluorescence and triplet state lifetimes of the complexes. Notably, the presence of zinc oxide nanoparticles increased the triplet quantum yield of phthalocyanines, however, the singlet oxygen quantum yield decreased. The study also examined the photodynamic inactivation of various planktonic cells and biofilms using all photosensitizers. The photodynamic antimicrobial chemotherapy activities were dose-dependent, and all cationic photosensitizers were highly effective in completely inactivating the microbes in both forms, as opposed to non-charged photosensitizers. For the supports, the chitosan modified PAN showed high efficacy due to improved hydrophilicity. Furthermore, the research was conducted on the photodegradation of 4-chlorophenol, methyl orange and methylene blue using Pc-anchored PAN and glass wool supports. The immobilized photosensitizers demonstrated a strong capacity for generating singlet oxygen in aqueous media, with the cationic Pc-PAN removing methylene blue more efficiently due to its adsorption and photodegradation abilities. All supports were recoverable, showing potential application for future use in the removal of microbes and organic pollutants. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Sindelo, Azole
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466614 , vital:76760 , DOI https://doi.org/10.21504/10962/466614
- Description: This thesis investigates the synthesie of metallophthalocyanines for potential use as photosensitizers in two applications: photodynamic antimicrobial chemotherapy and the photodegradation of organic pollutants. To achieve this, phthalocyanines with morpholine (substituted at alpha and beta position, to imine), ethyl and propyl pyrrolidine Schiff bases, asymmetrical mercaptobenzothiazole and morpholine substituents were synthesized for the first time. All nitrogen containing phthalocyanines were methylated to form cationic derivatives. Asymmetrical mercaptobenzothiazole were covalently linked to spherical and pyramidal zinc oxide nanoparticles, while the asymmetrical morpholine were conjugated to polyacrylonitrile (PAN) nanofibers, chitosan modified PAN and glass wool, while carboxylic acid containing phthalocyanines were also linked to glass wool. Various characterization techniques, including electronic spectroscopy, mass spectroscopy, nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR), elemental analysis, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscope (SEM), and time-resolved fluorescence measurements were employed to characterize all the phthalocyanine composites. The research aimed to establish general trends in fluorescence quantum yields, triplet and singlet oxygen generation, photodegradation rates, and fluorescence and triplet state lifetimes of the complexes. Notably, the presence of zinc oxide nanoparticles increased the triplet quantum yield of phthalocyanines, however, the singlet oxygen quantum yield decreased. The study also examined the photodynamic inactivation of various planktonic cells and biofilms using all photosensitizers. The photodynamic antimicrobial chemotherapy activities were dose-dependent, and all cationic photosensitizers were highly effective in completely inactivating the microbes in both forms, as opposed to non-charged photosensitizers. For the supports, the chitosan modified PAN showed high efficacy due to improved hydrophilicity. Furthermore, the research was conducted on the photodegradation of 4-chlorophenol, methyl orange and methylene blue using Pc-anchored PAN and glass wool supports. The immobilized photosensitizers demonstrated a strong capacity for generating singlet oxygen in aqueous media, with the cationic Pc-PAN removing methylene blue more efficiently due to its adsorption and photodegradation abilities. All supports were recoverable, showing potential application for future use in the removal of microbes and organic pollutants. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
Metal–organic framework-based heterogeneous catalysts with tailored active sites for precise oxidative transformations
- Hulushe, Siyabonga Theophillus
- Authors: Hulushe, Siyabonga Theophillus
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466581 , vital:76754
- Description: Access restricted. Exected release in 2025. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Hulushe, Siyabonga Theophillus
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466581 , vital:76754
- Description: Access restricted. Exected release in 2025. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
Microplastics as potential vectors for selected organic chemical pollutants in river ecosystems
- Authors: Tumwesigye, Edgar
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466677 , vital:76766 , DOI https://doi.org/10.21504/10962/466677
- Description: Microplastics (MPs) as pollutants in river ecosystems have received considerable research attention in recent years. However, in Africa, research on MPs is sparse, and more needs to be done. Empirical evidence suggests that MP can act as vectors of organic chemical pollutants due to their diverse functional groups and other physical-chemical properties, such as their small sizes, crystal structure and porosity. MPs acting as vectors of chemical pollutants, adds to the complexity of understanding the risk posed to both the ecosystem and human health. Regarding the so-called vector effect, the role of seasonality, land use type, adsorption kinetics, and MP properties has yet to receive the necessary research in the literature, especially concerning pharmaceutical active compounds and other organic pollutants in river systems. This is particularly true for Africa, including South Africa. This study, therefore, aimed to fill these existing research gaps. Overall, the study aimed to investigate the potential of selected microplastic polymers of a particular size range as vectors of organic pollutants in urban rivers within the Eastern Cape of South Africa. To achieve this aim, the study explored the influence of spatial-temporal variability, MPs particle sizes, and various physicochemical variables on the adsorption of antibiotics: Sulfamethoxazole, ciprofloxacin, and endocrine disruptors: 17β-Estradiol, 4-(2, 6-dimethyl-2-heptyl) phenol. The adsorption kinetics mechanism was also investigated and established. Polyethylene Terephthalate (PET) and polypropylene (PP) MPs were seasonally deployed once in the summer and autumn seasons, i.e. 20th January 2022 in Bloukrans River and 21st January 2022 in Swartkops River for the summer season and 7th April 2022 in Bloukrans River and 8th April 2022 in Swartkops River for the autumn season. Deployed MPs were of two size ranges, type 1 (2 mm<-≤5 mm) and type 2 (0.5mm<-≤2 mm). The sites where the MPs were deployed had different land use practices: informal settlements, discharge points of wastewater treatment works (WWTWs), agricultural farms, and control sites, considered as the least impacted sites. This was done to analyse land use types' role in the adsorption of chemical pollutants onto MPs. MPs were retrieved in periodic intervals of 7 days, 14 days and 35days calculated based on the day of deployment for both summer and autumn seasons and analysed for Sulfamethoxazole, Ciprofloxacin, 17β-Estradiol, 4-(2, 6-dimethyl-2-heptyl) phenol using high-resolution liquid chromatography–mass spectrometry LC-MS/MS equipped with a triple quadrupole (QqQ) analyser. Concurrent with MP retrieval water physicochemical variables: pH, dissolved oxygen (DO), temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids, total alkalinity and total hardness. The adsorption kinetics mechanism was studied in the laboratory between PET and PP of two size ranges and Sulfamethoxazole, Ciprofloxacin, and 17β-Estradiol model chemical. The results indicate that land use practices significantly impacted the concentration of the adsorbed chemicals on MPs. Sites downstream of the WWTW had higher concentrations of Sulfamethoxazole: 11119.6001±12552.4120ngL-1 and ciprofloxacin: 30285.19± 28783.7821ngL-1 adsorbed onto MPs in the Bloukrans River compared to the concentration of same compounds from other land use types along the same River catchment. Agriculturally impacted sites had higher concentrations of 17β-Estradiol on MPs; 11624.5611 ± 15382.2923ngL-1 and 100.3635± 29.6321ngL-1 in Swartkops and Bloukrans Rivers respectively compared to other sites. These results suggest that land use is an essential factor influencing chemical inputs into rivers and their adsorption onto MPs. Adsorption was higher for the MP of smaller sizes compared to MPs with bigger sizes, indicating that size is an essential factor that influences the vector effects of MPs. Adsorption was significantly higher after 35 days than all other days during the two seasons (P< 0.05). The adoption kinetics data fitted well with the pseudo-second-order model (R2> 0.99), indicating that chemisorption mechanisms may be the rate-limiting step. Data did not fit the intraparticle diffusion model. Both film diffusion and intraparticle diffusion possibly influenced the rate-limiting adsorption step simultaneously. Regarding the relationship between adsorption and water physico-chemical variables, of special interest a positive correlation between total alkalinity, electrical conductivity, total hardness, and total suspended salts (TDS) and the concentration of the adsorbed chemicals was observed. While the relationship between adsorption and dissolved oxygen was negative. The physicochemical variables with a positive relationship with adsorption are indicative of pollution. Therefore, the result suggests that increasing pollution tends to favour higher adsorption. The results in this study highlight the insights on i) the influence of land use on adsorption, ii) the role of exposure duration on adsorption, iii) the influence of seasonality and MP sizes on adsorption iv) relationship between water physicochemical parameters and adsorption as well as v) establishing adsorption kinetic mechanism. These findings are critical to better understanding the so-called vector effects of MPs and the management associated with MPs in river systems and form essential data sets needed in developing effective pollution mitigation strategies that are region-specific. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Tumwesigye, Edgar
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466677 , vital:76766 , DOI https://doi.org/10.21504/10962/466677
- Description: Microplastics (MPs) as pollutants in river ecosystems have received considerable research attention in recent years. However, in Africa, research on MPs is sparse, and more needs to be done. Empirical evidence suggests that MP can act as vectors of organic chemical pollutants due to their diverse functional groups and other physical-chemical properties, such as their small sizes, crystal structure and porosity. MPs acting as vectors of chemical pollutants, adds to the complexity of understanding the risk posed to both the ecosystem and human health. Regarding the so-called vector effect, the role of seasonality, land use type, adsorption kinetics, and MP properties has yet to receive the necessary research in the literature, especially concerning pharmaceutical active compounds and other organic pollutants in river systems. This is particularly true for Africa, including South Africa. This study, therefore, aimed to fill these existing research gaps. Overall, the study aimed to investigate the potential of selected microplastic polymers of a particular size range as vectors of organic pollutants in urban rivers within the Eastern Cape of South Africa. To achieve this aim, the study explored the influence of spatial-temporal variability, MPs particle sizes, and various physicochemical variables on the adsorption of antibiotics: Sulfamethoxazole, ciprofloxacin, and endocrine disruptors: 17β-Estradiol, 4-(2, 6-dimethyl-2-heptyl) phenol. The adsorption kinetics mechanism was also investigated and established. Polyethylene Terephthalate (PET) and polypropylene (PP) MPs were seasonally deployed once in the summer and autumn seasons, i.e. 20th January 2022 in Bloukrans River and 21st January 2022 in Swartkops River for the summer season and 7th April 2022 in Bloukrans River and 8th April 2022 in Swartkops River for the autumn season. Deployed MPs were of two size ranges, type 1 (2 mm<-≤5 mm) and type 2 (0.5mm<-≤2 mm). The sites where the MPs were deployed had different land use practices: informal settlements, discharge points of wastewater treatment works (WWTWs), agricultural farms, and control sites, considered as the least impacted sites. This was done to analyse land use types' role in the adsorption of chemical pollutants onto MPs. MPs were retrieved in periodic intervals of 7 days, 14 days and 35days calculated based on the day of deployment for both summer and autumn seasons and analysed for Sulfamethoxazole, Ciprofloxacin, 17β-Estradiol, 4-(2, 6-dimethyl-2-heptyl) phenol using high-resolution liquid chromatography–mass spectrometry LC-MS/MS equipped with a triple quadrupole (QqQ) analyser. Concurrent with MP retrieval water physicochemical variables: pH, dissolved oxygen (DO), temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids, total alkalinity and total hardness. The adsorption kinetics mechanism was studied in the laboratory between PET and PP of two size ranges and Sulfamethoxazole, Ciprofloxacin, and 17β-Estradiol model chemical. The results indicate that land use practices significantly impacted the concentration of the adsorbed chemicals on MPs. Sites downstream of the WWTW had higher concentrations of Sulfamethoxazole: 11119.6001±12552.4120ngL-1 and ciprofloxacin: 30285.19± 28783.7821ngL-1 adsorbed onto MPs in the Bloukrans River compared to the concentration of same compounds from other land use types along the same River catchment. Agriculturally impacted sites had higher concentrations of 17β-Estradiol on MPs; 11624.5611 ± 15382.2923ngL-1 and 100.3635± 29.6321ngL-1 in Swartkops and Bloukrans Rivers respectively compared to other sites. These results suggest that land use is an essential factor influencing chemical inputs into rivers and their adsorption onto MPs. Adsorption was higher for the MP of smaller sizes compared to MPs with bigger sizes, indicating that size is an essential factor that influences the vector effects of MPs. Adsorption was significantly higher after 35 days than all other days during the two seasons (P< 0.05). The adoption kinetics data fitted well with the pseudo-second-order model (R2> 0.99), indicating that chemisorption mechanisms may be the rate-limiting step. Data did not fit the intraparticle diffusion model. Both film diffusion and intraparticle diffusion possibly influenced the rate-limiting adsorption step simultaneously. Regarding the relationship between adsorption and water physico-chemical variables, of special interest a positive correlation between total alkalinity, electrical conductivity, total hardness, and total suspended salts (TDS) and the concentration of the adsorbed chemicals was observed. While the relationship between adsorption and dissolved oxygen was negative. The physicochemical variables with a positive relationship with adsorption are indicative of pollution. Therefore, the result suggests that increasing pollution tends to favour higher adsorption. The results in this study highlight the insights on i) the influence of land use on adsorption, ii) the role of exposure duration on adsorption, iii) the influence of seasonality and MP sizes on adsorption iv) relationship between water physicochemical parameters and adsorption as well as v) establishing adsorption kinetic mechanism. These findings are critical to better understanding the so-called vector effects of MPs and the management associated with MPs in river systems and form essential data sets needed in developing effective pollution mitigation strategies that are region-specific. , Thesis (PhD) -- Faculty of Science, Institute for Water Research, 2024
- Full Text:
- Date Issued: 2024-10-11
Mining MeerKAT data for minute to hour timescale transients and variable sources
- Authors: Gcilitshana, Sihle
- Date: 2024-10-11
- Subjects: MeerKAT , Astronomy Data processing , Radio astronomy , Pipelining (Electronics) , Active galactic nuclei
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464886 , vital:76554
- Description: In radio astronomy, minute-to-hour timescale transients and variable sources present an understudied population. We now have an unprecedented view of the transient radio sky due to the advent of new telescopes (such as the MeerKAT) with high instantaneous sensitivity, excellent snapshot imaging capabilities, and a large field of view. We can now probe into this population. This thesis presents the search for minute-to-hour timescale transient and variable sources in two of MeerKAT archival observations: the COSMOS and MACS J2140.2−2339 fields. The fields were observed for eight and five hours at the UHF band, respectively. We employed the PARROT transient and variable search pipeline currently being developed by the RATT group at Rhodes University. The pipeline’s input is a cross-calibrated measurement set, and its outputs are light curves extracted from all the sources in the restored image of the field. Using the light curves from the pipeline, we detected two variable sources in the COSMOS field, scintillating Active Galactic Nuclei (AGNs), which are most likely caused by the turbulent plasma in the interstellar medium. Due to persistent ionospheric diffraction, no variable sources were detected in the MACS J2140.2−2339 field, and no transients were detected in either field. The thesis also highlights areas where improvements to the PARROT pipeline can be implemented. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Gcilitshana, Sihle
- Date: 2024-10-11
- Subjects: MeerKAT , Astronomy Data processing , Radio astronomy , Pipelining (Electronics) , Active galactic nuclei
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464886 , vital:76554
- Description: In radio astronomy, minute-to-hour timescale transients and variable sources present an understudied population. We now have an unprecedented view of the transient radio sky due to the advent of new telescopes (such as the MeerKAT) with high instantaneous sensitivity, excellent snapshot imaging capabilities, and a large field of view. We can now probe into this population. This thesis presents the search for minute-to-hour timescale transient and variable sources in two of MeerKAT archival observations: the COSMOS and MACS J2140.2−2339 fields. The fields were observed for eight and five hours at the UHF band, respectively. We employed the PARROT transient and variable search pipeline currently being developed by the RATT group at Rhodes University. The pipeline’s input is a cross-calibrated measurement set, and its outputs are light curves extracted from all the sources in the restored image of the field. Using the light curves from the pipeline, we detected two variable sources in the COSMOS field, scintillating Active Galactic Nuclei (AGNs), which are most likely caused by the turbulent plasma in the interstellar medium. Due to persistent ionospheric diffraction, no variable sources were detected in the MACS J2140.2−2339 field, and no transients were detected in either field. The thesis also highlights areas where improvements to the PARROT pipeline can be implemented. , Thesis (MSc) -- Faculty of Science, Physics and Electronics, 2024
- Full Text:
- Date Issued: 2024-10-11
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
- Authors: Lazar, Sofia
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465000 , vital:76564
- Description: Water 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, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Lazar, Sofia
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465000 , vital:76564
- Description: Water 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, 2024
- Full Text:
- Date Issued: 2024-10-11
Moral disgust in Klaus Mann’s Mephisto and Goethe’s Faust
- Authors: Neilson, Christopher John
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465934 , vital:76669
- Description: This thesis investigates the presence and effects of moral emotions within Klaus Mann’s Mephisto (1936) and Goethe’s Faust (1808) with a focus on moral disgust as understood through the theories of P. Rozin and J. Haidt. The thesis also investigates the intertextual links between Goethe’s Faust and Klaus Mann’s Mephisto, namely the presence of the katabasis and anabasis motifs found in classical literature. This is undertaken with the aim to highlight the use of moral emotions as a novel approach to the study of literature. The Faust legend features an important moment when the Faust figure enters into a deal with the devil in hopes of gaining some transitory reward in exchange for his soul, with Goethe’s Faust being the most popular rendition of the German Faust legend. It is a play that depicts the life of a restless scholar who enters into a pact with a demon named Mephistopheles in the promise that Faust will receive pleasure without satisfaction. Shortly after the National Socialists came into power in Germany in 1933, Klaus Mann would write his own interpretation of the Faust motif in response to the Nazi reign. Klaus Mann’s Mephisto details the meteoric rise of the stage-actor Hendrik Höfgen who makes a ‘deal with the devil’ by collaborating with the Nazi elite in order to further his own acting career. Mephisto is devoid of any supernatural elements; this thus removes any supernatural influence on the actions of the Nazis and the protagonist Höfgen. The moral emotion of disgust, and thus also self-directed disgust and self-knowledge, eventually saves Faust, but there is no divine force to redeem Höfgen, nor is there an actual devil or demon to blame. , Thesis (MA) -- Faculty of Humanities, Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Neilson, Christopher John
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465934 , vital:76669
- Description: This thesis investigates the presence and effects of moral emotions within Klaus Mann’s Mephisto (1936) and Goethe’s Faust (1808) with a focus on moral disgust as understood through the theories of P. Rozin and J. Haidt. The thesis also investigates the intertextual links between Goethe’s Faust and Klaus Mann’s Mephisto, namely the presence of the katabasis and anabasis motifs found in classical literature. This is undertaken with the aim to highlight the use of moral emotions as a novel approach to the study of literature. The Faust legend features an important moment when the Faust figure enters into a deal with the devil in hopes of gaining some transitory reward in exchange for his soul, with Goethe’s Faust being the most popular rendition of the German Faust legend. It is a play that depicts the life of a restless scholar who enters into a pact with a demon named Mephistopheles in the promise that Faust will receive pleasure without satisfaction. Shortly after the National Socialists came into power in Germany in 1933, Klaus Mann would write his own interpretation of the Faust motif in response to the Nazi reign. Klaus Mann’s Mephisto details the meteoric rise of the stage-actor Hendrik Höfgen who makes a ‘deal with the devil’ by collaborating with the Nazi elite in order to further his own acting career. Mephisto is devoid of any supernatural elements; this thus removes any supernatural influence on the actions of the Nazis and the protagonist Höfgen. The moral emotion of disgust, and thus also self-directed disgust and self-knowledge, eventually saves Faust, but there is no divine force to redeem Höfgen, nor is there an actual devil or demon to blame. , Thesis (MA) -- Faculty of Humanities, Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-10-11
Music in everyday life: an exploration into the various uses of music among restaurant servers in Makhanda
- Authors: Dlamini, Andile Sakhile
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466161 , vital:76702
- Description: Inspired by the theory of practice in everyday life and symbolic interactionist perspectives, this thesis offers an account and analysis of findings from a qualitative study. It aimed to investigate the everyday uses of music among restaurant servers (individuals) in Makhanda, on an intra-level of analysis. It explored music’s role in individuals’ lives, and how music as an art is influential in constructing their individuality or self in society. Ten in-depth interviews were conducted through face-to-face collaboration and an audio recording device. It was evident that music plays various roles in people’s lives. Music, seemingly intertwined with everyday life permits individuals to diversly use music, for instance with tackling their emotions and mood, as an accompaniment to tasks or even a symbol that serves subjective meaning to self, essentially transforming the routinized mundanity of every day. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Dlamini, Andile Sakhile
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466161 , vital:76702
- Description: Inspired by the theory of practice in everyday life and symbolic interactionist perspectives, this thesis offers an account and analysis of findings from a qualitative study. It aimed to investigate the everyday uses of music among restaurant servers (individuals) in Makhanda, on an intra-level of analysis. It explored music’s role in individuals’ lives, and how music as an art is influential in constructing their individuality or self in society. Ten in-depth interviews were conducted through face-to-face collaboration and an audio recording device. It was evident that music plays various roles in people’s lives. Music, seemingly intertwined with everyday life permits individuals to diversly use music, for instance with tackling their emotions and mood, as an accompaniment to tasks or even a symbol that serves subjective meaning to self, essentially transforming the routinized mundanity of every day. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
Navigating change: a critical analysis of social media’s role in shaping gender activists’ perspectives
- Authors: Dias, Sasha Elliot
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466128 , vital:76699
- Description: This research explores the unique challenges and opportunities that social media offers gender activists fighting for equality and social justice. It examines the negative and positive elements of social media, highlighting the ways it can be adopted to build communities, amplify voices, and advance social change in unique ways, but also the ways in which it can adversely contribute to existing power imbalances and inequalities. This research does not concentrate on any specific gender-based movement, but rather aims to understand how gender activists in South Africa have embraced social media in their local activism. The study followed a qualitative approach and collected the data through in-depth semi-structured interviews. It also followed a thematic framework in its analysis of the data collected from the interviews. The study found that, while online gender activism in South Africa faces challenges such as harassment and the digital gender divide, there is still progress in terms of community building and political engagement on social media. The findings suggest that, in spite of the challenges, social media can still be an important tool for advancing gender-based social justice in South Africa. This research made use of Counter-publics and Cyberfeminism as guiding theoretical frameworks. The theory of Counter-publics provides a valuable way of understanding how virtual groups emerge and challenge dominant societal norms and values. Cyberfeminism provides insight into how women have challenged contemporary inequalities through the adoption of technologies such as social media. As sub-components to Cyber-feminism, Intersectionality and Standpoint perspectives were used to understand how activists’ diverse identities and social positions influence their individual forms of activism. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Dias, Sasha Elliot
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466128 , vital:76699
- Description: This research explores the unique challenges and opportunities that social media offers gender activists fighting for equality and social justice. It examines the negative and positive elements of social media, highlighting the ways it can be adopted to build communities, amplify voices, and advance social change in unique ways, but also the ways in which it can adversely contribute to existing power imbalances and inequalities. This research does not concentrate on any specific gender-based movement, but rather aims to understand how gender activists in South Africa have embraced social media in their local activism. The study followed a qualitative approach and collected the data through in-depth semi-structured interviews. It also followed a thematic framework in its analysis of the data collected from the interviews. The study found that, while online gender activism in South Africa faces challenges such as harassment and the digital gender divide, there is still progress in terms of community building and political engagement on social media. The findings suggest that, in spite of the challenges, social media can still be an important tool for advancing gender-based social justice in South Africa. This research made use of Counter-publics and Cyberfeminism as guiding theoretical frameworks. The theory of Counter-publics provides a valuable way of understanding how virtual groups emerge and challenge dominant societal norms and values. Cyberfeminism provides insight into how women have challenged contemporary inequalities through the adoption of technologies such as social media. As sub-components to Cyber-feminism, Intersectionality and Standpoint perspectives were used to understand how activists’ diverse identities and social positions influence their individual forms of activism. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
No way to escape: a crime fiction
- Authors: Dzanibe, Nkosivumile
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465923 , vital:76668
- Description: This study presents a model for science engagement that incorporates journalistic approaches. This model emerges from a project that aimed to create engagement and communication around a genetically modified sugar cane variety, developed by the South African Sugarcane Research Institute (SASRI). In this project, we engaged with small scale growers in the North and South Coast region of KwaZulu-Natal. This study’s methodology is based in action research and an iterative approach to science communication and engagement. It draws and reflects on an action research cycle captured through video documentary as a way to effectively and thoroughly collect, analyse and interpret data and produce through the case study. Based on this action research process a model for science engagement is proposed and reflected on and interrogated by scientists and science communicators through a focus group engagement (see model here as part of this thesis): https://drive.google.com/file/d/14UD1qd4fPcqIZrkESq5v2wgJ1Y2Q7hON/view?usp=sharing. I reflect, using video, on this model and how it incorporates principles and techniques for public engagement drawn from different approaches to journalism and communication studies, I argue that science engagement can benefit from drawing from journalistic approaches to public engagement such as those emerging from development communication, public journalism and development journalism. The submission of this thesis includes various other videos as part of the overall thesis. , Thesis (MA) -- Faculty of Humanities, Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Dzanibe, Nkosivumile
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465923 , vital:76668
- Description: This study presents a model for science engagement that incorporates journalistic approaches. This model emerges from a project that aimed to create engagement and communication around a genetically modified sugar cane variety, developed by the South African Sugarcane Research Institute (SASRI). In this project, we engaged with small scale growers in the North and South Coast region of KwaZulu-Natal. This study’s methodology is based in action research and an iterative approach to science communication and engagement. It draws and reflects on an action research cycle captured through video documentary as a way to effectively and thoroughly collect, analyse and interpret data and produce through the case study. Based on this action research process a model for science engagement is proposed and reflected on and interrogated by scientists and science communicators through a focus group engagement (see model here as part of this thesis): https://drive.google.com/file/d/14UD1qd4fPcqIZrkESq5v2wgJ1Y2Q7hON/view?usp=sharing. I reflect, using video, on this model and how it incorporates principles and techniques for public engagement drawn from different approaches to journalism and communication studies, I argue that science engagement can benefit from drawing from journalistic approaches to public engagement such as those emerging from development communication, public journalism and development journalism. The submission of this thesis includes various other videos as part of the overall thesis. , Thesis (MA) -- Faculty of Humanities, Languages and Literatures, 2024
- Full Text:
- Date Issued: 2024-10-11
Optimising Integrated Multitrophic Aquaculture (IMTA) on a South African abalone farm
- Authors: Falade, Abiodun Emmanuel
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466712 , vital:76772 , DOI https://doi.org/10.21504/10962/466712
- Description: The efficiency of fed nutrient utilisation in integrated multitrophic aquaculture (IMTA) system was evaluated on a South African abalone farm. On many commercial abalone farms in South Africa, Haliotis midae are fed a combination of pelleted feed and live macroalgae cultured downstream in abalone effluent. This production technique reduces the discharge of dissolved nutrients into the environment and improves farm productivity as unquantified proportion of the waste metabolites is captured as macroalgal biomass. However, the solid waste from abalone culture tanks remains unutilised and discharged to the coastal environments. Thus, there is scope to improve the dissolved nutrients removal efficiency of the macroalgae and to reduce the discharge of particulate nutrients using detritus waste extractive organisms. The present study aimed at the production and environmental performance of a shore-based abalone/macroalgae IMTA improving farm in South Africa by improving the nutrient utilisation efficiency of farmed abalone and seaweed and testing the waste solids removal potential of a sea cucumber species. Monoculture systems, where abalone and seaweed were cultured separately, both in fresh seawater (salinity: 35 g/L), were compared with an integrated culture system where the seaweed (Ulva lacinulata) was cultured downstream in the wastewater flowing from abalone tanks that were up-channel. Based on the findings from quantifying the performance of these production systems, methods to improve the nutrient utilisation and production efficiencies of the production systems were explored. These assessed methods included (1) the removal of abalone biodeposits by detritus extractive sea cucumber production, (2) evaluating the potential of farmed macroalgae as supplement in formulated diet, and (3) replacing mineral fertilisers with eco-friendly live microbial fertilisers for seaweed farming. Furthermore, the overall environmental performance of the two farm systems was quantified using a life cycle analysis methodology. Monitoring of the nutrient flows through the monoculture and IMTA systems revealed that the highest inputs of nutrients (nitrogen and phosphorus) into the abalone and seaweed culture tanks of the two production systems were abalone feed pellet (70-81%) and mineral fertilisers respectively (63-93%). About 48-51% of the nitrogen supplied from the feed was utilised by abalone in the IMTA and monoculture systems, while the remaining portion was lost as organic waste nitrogen on the production tank floor (20-30%) and as dissolved nitrogen in post-abalone tank effluent (30-36%). In the seaweed tanks receiving abalone effluent (IMTA), 69% of the dissolved nitrogen input was absorbed by cultured Ulva while 25% of the nitrogen was lost to the post-seaweed effluent which returned to the environment. However, in the monoculture system, 52% of the nitrogen from supplemented inorganic fertiliser was absorbed by cultured Ulva while ca. 46% of the nutrient was lost to coastal waters through the post-seaweed effluent. Moreover, while the feed accounted for ca. 74-78% input of the phosphorus in abalone of the two production systems, not more than 19% and 13% of this phosphorus was utilised by H. midae in the IMTA and monoculture systems respectively, while the largest portions were lost as organic waste in the sediment (34-45%) and dissolved waste phosphorus in the effluent (33-54%). In the seaweed tanks, a small portion (11-15%) of supplied phosphorus was removed by farmed Ulva while 77-89% was lost in the post-seaweed effluent discharged to coastal environment. The substitution of 50% mineral fertilisers with live microbial fertilisers during seaweed production significantly reduced the discharge of dissolved nitrogen and phosphorus from macroalgae raceways to coastal environment by 55 and 45% respectively, without impacting their growth, yield and nutrient compositions. A life cycle analysis of the measured energy and nutrients utilisation efficiency of these production systems was compiled, and the impacts of the inputs and outputs from each production system on the environment was assessed. The electrical energy input to abalone and seaweed tanks constituted the highest contribution to all assessed environmental impact categories for the two production systems, followed by the contributions from the nutrients supplied to farmed abalone (formulated diet) and seaweed (mineral fertilisers). The impact of these inputs on the environment was most evident on marine aquatic ecotoxicity being 2.11E+03 kg 1.4-DB eq and 4.43E+03 kg 1.4-DB eq for IMTA and monoculture systems respectively. The measured impact of seaweed aquaculture on the environment was reduced by 50-52% when Ulva was cultured in abalone effluent (IMTA) compared to culture in fresh seawater (monoculture). However, the input of chemical fertilisers in the two systems of cultivation resulted in similar eutrophication potentials (8.09 - 8.41E-02 kg PO4--- eq). To reduce the solid waste discharge from abalone tanks, and create an additional high-value crop, an endemic sea cucumber species (Neostichopus grammatus) was introduced on the floor of the abalone culture tanks in a pilot abalone/detritivore/macroalgae IMTA system. The sea cucumber utilised the biodeposits in abalone tanks as food which reduced organic solid discharge to the environment by 11%. However, the sea cucumbers displayed poor nutrient utilisation, a negative growth rate (- 0.59% day-1) and 49% weight loss by the end of the trial that was probably due to sub-optimal habitat conditions (lack of a sand substrate). The potential of including farmed Ulva (IMTA and monoculture) meal in pelleted feed for H. midae was evaluated as a means of improving farming efficiency and reducing the levels of fishmeal and soya in the pellet. In an initial trial, Ulva was included at 12% dry weight in commercial diet and fed to farmed H. midae for 244 d. The 12% inclusion of IMTA and monoculture Ulva resulted in poor feed conversion and nutrient utilisation by H. midae. In a follow-up trial which tested graded inclusion levels of Ulva meal (0.75, 1.50, 3.00, 6.00 and 12.00%), the growth rate and feed utilisation of H. midae was enhanced at a 0.75-6.00% inclusion level of the seaweed in the diet, while at a 6.00-12.00% inclusion level growth rates and feed conversion efficiencies decreased. Therefore, it is recommended that for sub-adult South African abalone, up to 6.00% IMTA Ulva meal can be included in the diet formulation without impacting their growth performance and nutrient utilisation efficiency negatively. This present study contributes to the understanding of the nutrient utilisation dynamics on integrated abalone farms in South Africa. The evidence from the different trials suggests the IMTA techniques tested could be adopted to improve the production performance and reduce the impact of abalone farming on the environment. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Falade, Abiodun Emmanuel
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466712 , vital:76772 , DOI https://doi.org/10.21504/10962/466712
- Description: The efficiency of fed nutrient utilisation in integrated multitrophic aquaculture (IMTA) system was evaluated on a South African abalone farm. On many commercial abalone farms in South Africa, Haliotis midae are fed a combination of pelleted feed and live macroalgae cultured downstream in abalone effluent. This production technique reduces the discharge of dissolved nutrients into the environment and improves farm productivity as unquantified proportion of the waste metabolites is captured as macroalgal biomass. However, the solid waste from abalone culture tanks remains unutilised and discharged to the coastal environments. Thus, there is scope to improve the dissolved nutrients removal efficiency of the macroalgae and to reduce the discharge of particulate nutrients using detritus waste extractive organisms. The present study aimed at the production and environmental performance of a shore-based abalone/macroalgae IMTA improving farm in South Africa by improving the nutrient utilisation efficiency of farmed abalone and seaweed and testing the waste solids removal potential of a sea cucumber species. Monoculture systems, where abalone and seaweed were cultured separately, both in fresh seawater (salinity: 35 g/L), were compared with an integrated culture system where the seaweed (Ulva lacinulata) was cultured downstream in the wastewater flowing from abalone tanks that were up-channel. Based on the findings from quantifying the performance of these production systems, methods to improve the nutrient utilisation and production efficiencies of the production systems were explored. These assessed methods included (1) the removal of abalone biodeposits by detritus extractive sea cucumber production, (2) evaluating the potential of farmed macroalgae as supplement in formulated diet, and (3) replacing mineral fertilisers with eco-friendly live microbial fertilisers for seaweed farming. Furthermore, the overall environmental performance of the two farm systems was quantified using a life cycle analysis methodology. Monitoring of the nutrient flows through the monoculture and IMTA systems revealed that the highest inputs of nutrients (nitrogen and phosphorus) into the abalone and seaweed culture tanks of the two production systems were abalone feed pellet (70-81%) and mineral fertilisers respectively (63-93%). About 48-51% of the nitrogen supplied from the feed was utilised by abalone in the IMTA and monoculture systems, while the remaining portion was lost as organic waste nitrogen on the production tank floor (20-30%) and as dissolved nitrogen in post-abalone tank effluent (30-36%). In the seaweed tanks receiving abalone effluent (IMTA), 69% of the dissolved nitrogen input was absorbed by cultured Ulva while 25% of the nitrogen was lost to the post-seaweed effluent which returned to the environment. However, in the monoculture system, 52% of the nitrogen from supplemented inorganic fertiliser was absorbed by cultured Ulva while ca. 46% of the nutrient was lost to coastal waters through the post-seaweed effluent. Moreover, while the feed accounted for ca. 74-78% input of the phosphorus in abalone of the two production systems, not more than 19% and 13% of this phosphorus was utilised by H. midae in the IMTA and monoculture systems respectively, while the largest portions were lost as organic waste in the sediment (34-45%) and dissolved waste phosphorus in the effluent (33-54%). In the seaweed tanks, a small portion (11-15%) of supplied phosphorus was removed by farmed Ulva while 77-89% was lost in the post-seaweed effluent discharged to coastal environment. The substitution of 50% mineral fertilisers with live microbial fertilisers during seaweed production significantly reduced the discharge of dissolved nitrogen and phosphorus from macroalgae raceways to coastal environment by 55 and 45% respectively, without impacting their growth, yield and nutrient compositions. A life cycle analysis of the measured energy and nutrients utilisation efficiency of these production systems was compiled, and the impacts of the inputs and outputs from each production system on the environment was assessed. The electrical energy input to abalone and seaweed tanks constituted the highest contribution to all assessed environmental impact categories for the two production systems, followed by the contributions from the nutrients supplied to farmed abalone (formulated diet) and seaweed (mineral fertilisers). The impact of these inputs on the environment was most evident on marine aquatic ecotoxicity being 2.11E+03 kg 1.4-DB eq and 4.43E+03 kg 1.4-DB eq for IMTA and monoculture systems respectively. The measured impact of seaweed aquaculture on the environment was reduced by 50-52% when Ulva was cultured in abalone effluent (IMTA) compared to culture in fresh seawater (monoculture). However, the input of chemical fertilisers in the two systems of cultivation resulted in similar eutrophication potentials (8.09 - 8.41E-02 kg PO4--- eq). To reduce the solid waste discharge from abalone tanks, and create an additional high-value crop, an endemic sea cucumber species (Neostichopus grammatus) was introduced on the floor of the abalone culture tanks in a pilot abalone/detritivore/macroalgae IMTA system. The sea cucumber utilised the biodeposits in abalone tanks as food which reduced organic solid discharge to the environment by 11%. However, the sea cucumbers displayed poor nutrient utilisation, a negative growth rate (- 0.59% day-1) and 49% weight loss by the end of the trial that was probably due to sub-optimal habitat conditions (lack of a sand substrate). The potential of including farmed Ulva (IMTA and monoculture) meal in pelleted feed for H. midae was evaluated as a means of improving farming efficiency and reducing the levels of fishmeal and soya in the pellet. In an initial trial, Ulva was included at 12% dry weight in commercial diet and fed to farmed H. midae for 244 d. The 12% inclusion of IMTA and monoculture Ulva resulted in poor feed conversion and nutrient utilisation by H. midae. In a follow-up trial which tested graded inclusion levels of Ulva meal (0.75, 1.50, 3.00, 6.00 and 12.00%), the growth rate and feed utilisation of H. midae was enhanced at a 0.75-6.00% inclusion level of the seaweed in the diet, while at a 6.00-12.00% inclusion level growth rates and feed conversion efficiencies decreased. Therefore, it is recommended that for sub-adult South African abalone, up to 6.00% IMTA Ulva meal can be included in the diet formulation without impacting their growth performance and nutrient utilisation efficiency negatively. This present study contributes to the understanding of the nutrient utilisation dynamics on integrated abalone farms in South Africa. The evidence from the different trials suggests the IMTA techniques tested could be adopted to improve the production performance and reduce the impact of abalone farming on the environment. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-10-11
Participatory mapping of key drivers of ecological change and analysing equity dimensions of ecosystem services flow in the Kat River Catchment
- Authors: Seriki, Esther Ahuoiza
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465024 , vital:76566
- Description: Rivers are important ecosystems which supply ecosystem services critical to social-economic well-being. However, many rivers are degraded due to human activities. Degradation of river systems compromises the quality and quantity of ecosystem services they can supply. Managing important drivers of ecological change requires broad-based stakeholder participation to mobilise collective actions for an effective rehabilitation strategy. This study looked at two crucial research objectives in the Kat River catchment. The first was to undertake a multidimensional, participatory, engaged mapping of ecological changes, as well as current and changing ecosystem services in the Kat River catchment, and the second was to analyse the equity dimensions of ecosystem services flow in the Kat River catchment. Data were collected through semi-structured interviews and participatory GIS mapping exercises. A purposive sampling method was applied to recruit research participants for interviews and workshops. Between March 13th and May 31st, 2023, thirty-one (31) participants representing four social groups, non-farming individuals, catchment management forum members, commercial and subsistence farmers, participated in interviews. Additionally, twenty-two (22) stakeholders attended 2-day workshops held between 20−21 April 2022, and 30−31 May 2023. Data collected from interviews and workshops were analysed using thematic analysis. The results of stakeholder perceptions regarding the perceived ecological changes and their key drivers in the Kat River catchment revealed a concerning trend. Participants reported significant changes to the catchment area over time, including increased occurrences of flooding and water pollution and decreased aquatic biodiversity. Furthermore, degradation of ecosystem services, such as water quality, availability of medicinal plants, reeds, and fish populations, was noted. These environmental shifts have been accompanied by a rise in social-economic burdens, including the prevalence of water-borne diseases, cultural burdens (particularly the inability of certain groups to access ancestral grave sites) and declining fish populations. These findings emphasise the urgent need for intervention strategies to mitigate further degradation of the catchment area and safeguard the well-being of both the human population and the integrity of the ecosystems. Recommended intervention measures include improving wastewater management practices and creating targeted public awareness campaigns. By addressing these challenges, stakeholders can work towards preserving the integrity of the catchment area, protecting water resources and conserving biodiversity for future generations. The equity dimensions (distributive and procedural equity) analysis revealed notable disparities in access to the benefits of ecosystem services, as well as in participation of residents in the Kat River Water Users Association. Certain social groups, such as commercial farmers, were observed to receive more benefits from ecosystem services, while other groups, including the elderly and disabled individuals, seem to be negatively impacted by the activities of those who benefit most from ecosystem services in the Kat River catchment. This raises not only an equity issue but also the issue of how costs are externalised by certain groups. Of particular concern was the finding that seventy (70) per cent of the research participants were not aware of the presence of the Kat River Water Users Association, raising concerns about procedural equity in water resource management processes. Additionally, ninety (90) per cent of the participants had the perception that there was unfair water access and allocation across the various social groups, highlighting possible distributive inequities. The participants expressed a clear interest in learning more about the existence and operation of the Kat River Water Users Association, signalling a need for increased awareness and participation among social groups. Addressing these equity concerns is crucial to ensure that water resource management processes are designed to provide all stakeholders and water-dependent actors with equitable and fair access to decision making. Moving forward, efforts should be directed towards raising awareness of the Kat River Water Users Association and to promoting inclusive participation among all social groups. This awareness may involve targeted outreach campaigns, community engagement initiatives and policy reforms to foster more equitable water governance practices within the catchment. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Seriki, Esther Ahuoiza
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465024 , vital:76566
- Description: Rivers are important ecosystems which supply ecosystem services critical to social-economic well-being. However, many rivers are degraded due to human activities. Degradation of river systems compromises the quality and quantity of ecosystem services they can supply. Managing important drivers of ecological change requires broad-based stakeholder participation to mobilise collective actions for an effective rehabilitation strategy. This study looked at two crucial research objectives in the Kat River catchment. The first was to undertake a multidimensional, participatory, engaged mapping of ecological changes, as well as current and changing ecosystem services in the Kat River catchment, and the second was to analyse the equity dimensions of ecosystem services flow in the Kat River catchment. Data were collected through semi-structured interviews and participatory GIS mapping exercises. A purposive sampling method was applied to recruit research participants for interviews and workshops. Between March 13th and May 31st, 2023, thirty-one (31) participants representing four social groups, non-farming individuals, catchment management forum members, commercial and subsistence farmers, participated in interviews. Additionally, twenty-two (22) stakeholders attended 2-day workshops held between 20−21 April 2022, and 30−31 May 2023. Data collected from interviews and workshops were analysed using thematic analysis. The results of stakeholder perceptions regarding the perceived ecological changes and their key drivers in the Kat River catchment revealed a concerning trend. Participants reported significant changes to the catchment area over time, including increased occurrences of flooding and water pollution and decreased aquatic biodiversity. Furthermore, degradation of ecosystem services, such as water quality, availability of medicinal plants, reeds, and fish populations, was noted. These environmental shifts have been accompanied by a rise in social-economic burdens, including the prevalence of water-borne diseases, cultural burdens (particularly the inability of certain groups to access ancestral grave sites) and declining fish populations. These findings emphasise the urgent need for intervention strategies to mitigate further degradation of the catchment area and safeguard the well-being of both the human population and the integrity of the ecosystems. Recommended intervention measures include improving wastewater management practices and creating targeted public awareness campaigns. By addressing these challenges, stakeholders can work towards preserving the integrity of the catchment area, protecting water resources and conserving biodiversity for future generations. The equity dimensions (distributive and procedural equity) analysis revealed notable disparities in access to the benefits of ecosystem services, as well as in participation of residents in the Kat River Water Users Association. Certain social groups, such as commercial farmers, were observed to receive more benefits from ecosystem services, while other groups, including the elderly and disabled individuals, seem to be negatively impacted by the activities of those who benefit most from ecosystem services in the Kat River catchment. This raises not only an equity issue but also the issue of how costs are externalised by certain groups. Of particular concern was the finding that seventy (70) per cent of the research participants were not aware of the presence of the Kat River Water Users Association, raising concerns about procedural equity in water resource management processes. Additionally, ninety (90) per cent of the participants had the perception that there was unfair water access and allocation across the various social groups, highlighting possible distributive inequities. The participants expressed a clear interest in learning more about the existence and operation of the Kat River Water Users Association, signalling a need for increased awareness and participation among social groups. Addressing these equity concerns is crucial to ensure that water resource management processes are designed to provide all stakeholders and water-dependent actors with equitable and fair access to decision making. Moving forward, efforts should be directed towards raising awareness of the Kat River Water Users Association and to promoting inclusive participation among all social groups. This awareness may involve targeted outreach campaigns, community engagement initiatives and policy reforms to foster more equitable water governance practices within the catchment. , Thesis (MSc) -- Faculty of Science, Institute for Water Research, 2024
- Full Text:
- Date Issued: 2024-10-11
Perceptions, knowledge, and attitudes towards employee wellness programmes among private high school educators in South Africa
- Authors: Moroane, Motheo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464765 , vital:76543
- Description: Organisations can perform more effectively if their employees' health and wellbeing are optimal and considered a priority. Evidence suggests that employee wellness programmes (EWP) increase employee and overall organisational health, effectiveness, and performance. The World Competitive Report has ranked South Africa poorly regarding Human Resource Management and Development. The South African education system accommodates more than 12,3 million high school learners, 2 938 primary and secondary schools and only 37 500 educators. The South African Department of Education has implemented several initiatives to improve education and the wellbeing of South African educators. However, research investigating the work-related health and wellbeing of educators indicates that burnout, job dissatisfaction, depression, anxiety, and infections, including HIV and AIDS, TB, and Malaria, are prominent among educators. The objectives of this research were to explore whether age, sex, education, and years employed as an educator will significantly impact South African private high school educators' (i) perceptions, (ii) knowledge and (iii) attitudes toward employee wellness programmes, and to (iv) using the answers from a questionnaire; to propose a normative holistic employee wellness programme for private high school educators in South Africa. To fulfil these objectives a mixed-methods study approach was adopted. The study used a once-off, specifically designed questionnaire that explored EWP perceptions, knowledge, and attitudes among South African private high school educators. The results of the questionnaire indicated that firstly, the highest education obtained significantly influenced how educators rated their knowledge of employee wellness programmes. Specifically, the higher the level of education/more educated educators were, the better employees rated their knowledge of wellness programmes. Secondly, gender emerged as a significant factor. Female educators were more inclined to better rate their perception and knowledge regarding whether the workplace could provide valuable source of information on employee health and wellbeing. In other words, female educators rated their knowledge and perceived the workplace as a potentially valuable source of information on employee wellness programmes, than men did. Thirdly, educators with more than ten years of experience were more likely to participate in employee wellness programmes. Lastly, younger employees (younger than the age of 41 years) had the attitude that stigmas may prevent employees from participating in employee wellness programmes and seeking counselling, testing and treatment. Based on these findings, a tailored holistic EWP model was developed to address the specific needs of private high school educators, aiming to enhance their overall wellbeing. In conclusion, this dissertation emphasized the importance of EWP in improving the health and performance of educators in South Africa’s private high schools. Importantly, this study identified unique challenges faced by these educators and highlighted the need for tailored wellness initiatives. Lastly, this study emphasizes the importance of addressing educator wellbeing to enhance the overall educational environment in South Africa. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Moroane, Motheo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464765 , vital:76543
- Description: Organisations can perform more effectively if their employees' health and wellbeing are optimal and considered a priority. Evidence suggests that employee wellness programmes (EWP) increase employee and overall organisational health, effectiveness, and performance. The World Competitive Report has ranked South Africa poorly regarding Human Resource Management and Development. The South African education system accommodates more than 12,3 million high school learners, 2 938 primary and secondary schools and only 37 500 educators. The South African Department of Education has implemented several initiatives to improve education and the wellbeing of South African educators. However, research investigating the work-related health and wellbeing of educators indicates that burnout, job dissatisfaction, depression, anxiety, and infections, including HIV and AIDS, TB, and Malaria, are prominent among educators. The objectives of this research were to explore whether age, sex, education, and years employed as an educator will significantly impact South African private high school educators' (i) perceptions, (ii) knowledge and (iii) attitudes toward employee wellness programmes, and to (iv) using the answers from a questionnaire; to propose a normative holistic employee wellness programme for private high school educators in South Africa. To fulfil these objectives a mixed-methods study approach was adopted. The study used a once-off, specifically designed questionnaire that explored EWP perceptions, knowledge, and attitudes among South African private high school educators. The results of the questionnaire indicated that firstly, the highest education obtained significantly influenced how educators rated their knowledge of employee wellness programmes. Specifically, the higher the level of education/more educated educators were, the better employees rated their knowledge of wellness programmes. Secondly, gender emerged as a significant factor. Female educators were more inclined to better rate their perception and knowledge regarding whether the workplace could provide valuable source of information on employee health and wellbeing. In other words, female educators rated their knowledge and perceived the workplace as a potentially valuable source of information on employee wellness programmes, than men did. Thirdly, educators with more than ten years of experience were more likely to participate in employee wellness programmes. Lastly, younger employees (younger than the age of 41 years) had the attitude that stigmas may prevent employees from participating in employee wellness programmes and seeking counselling, testing and treatment. Based on these findings, a tailored holistic EWP model was developed to address the specific needs of private high school educators, aiming to enhance their overall wellbeing. In conclusion, this dissertation emphasized the importance of EWP in improving the health and performance of educators in South Africa’s private high schools. Importantly, this study identified unique challenges faced by these educators and highlighted the need for tailored wellness initiatives. Lastly, this study emphasizes the importance of addressing educator wellbeing to enhance the overall educational environment in South Africa. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
- Full Text:
- Date Issued: 2024-10-11
Photodynamic anticancer and antimicrobial activities of aza-BODIPY and porphyrinbased photosensitisers and their non-linear properties
- Authors: Molupe, Nthabeleng Regina
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466603 , vital:76758 , DOI https://doi.org/10.21504/10962/466603
- Description: New aza-BODIPY dyes and porphyrins were synthesised and characterised so that photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) activity studies could be performed. Several strategies were explored to achieve targeted nanoplatforms or biocompatible nanoplatforms to enhance the suitability of these compounds for use in PDT. Following earlier MSc research on the encapsulation of halogenated boron dipyrromethene (BODIPY) dyes into Pluronic® micelles, similar nanomicelles were prepared to encapsulate halogenated boron aza-dipyrromethene (aza-BODPY) dyes to enhance their aqueous solubility. However, the 1,7-dimethylthiophenyl- 2,6-diiodo-3,5-diphenyl (1) and 1,7-di-methylthiophenyl-2,6-diiodo- 3,5-dithien-3-yl (2) aza-BODIPY dyes that were prepared in this context were found to degrade when encapsulated. A different strategy was then followed in which gold nanoparticles (AuNPs) were conjugated to 1 and 2 via Au-S interactions to form biocompatible aza-BODIPY-AuNP conjugates (1-AuNP and 2-AuNP). This strategy was successful, and favourable IC50 values of 3.60 and 10.0 μM for 1-AuNP and 2- AuNP were obtained during in vitro PDT activity studies against MCF-7 human breast cancer cells, respectively, while values of 11.0 and 12.8 μM were obtained for 1 and 2. To further explore the preparation of better-targeted aza-BODIPY photosensitiser dyes, folic acid (FA) was conjugated to 1,7-dihydroxyphenyl-2,6-diiodo-3,5-di-4- bromophenyl (3) and 1,7-di-4-bromo-2,6-diiodo-3,5-dihydroxyphenylphenyl (4) aza- BODIPYs via ester bonds. Not only was the conjugation to form 3-FA and 4-FA successful, but the conjugated dyes are water-soluble, which is advantageous for drug transport in the context of PDT. These conjugates were applied in vitro against MCF-7 cancer cells and were found to have relatively high activities with IC50 values of 0.91 and 7.48 μM for 3-FA and 4-FA, respectively, while values of 11.3 and 13.0 μM were obtained for the non-conjugated 3 and 4 dyes. In a similar manner, tin (IV) and indium (III) tetrapyridylporphyrins (5 and 6) were axially conjugated to folic acid via ester bonds (5-FA and 6-FA). The conjugation was successful and enhanced the PDT activities of the dyes MCF-7 cancer cells in vitro from 48.2 to 29.6 μM for 5 and 5-FA, and from 43.9 to 13.3 μM for 6 and 6-FA. Relatively high dark toxicity was observed for 6-FA of 26.1 μM. When the nitrogen atoms of the meso-pyridyl rings were quaternized (5-FAQ and 6-FAQ) to further enhance the aqueous solubility of the complexes, it was not possible to calculate an IC50 value. When octanol-water partition coefficients (Log P) were calculated by the shake flask method, values of −0.70 and −1.70 were obtained for 5-FAQ and 6-FAQ, respectively. This provides evidence that the dyes are too water-soluble and not sufficiently lipophilic. The PACT activity properties of the synthesised diiodinated aza-BODIPYs were studied against Staphylococcus aureus (S. aureus) through photoirradiation for 60 min with Thorlabs M660L4 (280 mW.cm−2) and M730L4 (160 mW.cm−2) light emitting diodes (LEDs) mounted on the illumination chamber of Modulight® 7710-680 medical laser system providing doses at the well-plate of 100 and 57 J.cm−2.min−1. Aza- BODIPYs 2, 3 and 4 all inhibited the growth of S. aureus but with relatively low Log10 reductions of 1.37, 1.20 and 0.20. In contrast, aza-BODIPY 1 was found to have a Log10 reduction of 7.82. The PACT activities of free base and Sn(IV) 5-[4-(3- bromoethylcarboxyamidyl)phenyl]-10,15,20-triphenylporphyrins (7 and 8) prepared by Dr Balaji Babu (New Journal of Chemistry 2022, 46, 5288-5295) were tested against S. aureus to determine whether adding a triphenylphosphonium moiety to form free base and Sn(IV) 5-[4-(triphenylphosphonium)ethylcarboxyamidyl)phenyl]-10,15,20- triphenylporphyrin (18 and 19) enhances the photo-induced antibacterial activity, in addition to optimising the PDT properties due to its mitochondria-targeting properties. The PACT activities obtained against S. aureus were not favourable, but 18 exhibited enhanced activity across the studied concentration range. The potential utility of aza-BODIPY dyes 1-4 and their non-iodinated analogues (1a- 4a) for optical limiting applications was analysed by carrying out a series of Z-scan measurements, since dyes of this type have large ground state dipole moments, and this can enhance the non-linear optical limiting response. All the aza-BODIPY dyes under investigation exhibited intense non-linear absorption (NLA) behaviour with Zscan profiles that contain significant reverse saturable absorption (RSA) responses. Aza-BODIPYs 1, 2a, 2, 3, 4a, and 4 decreased the transmitted intensity of the strong laser beam to less than 50% of the linear response in organic solutions with a fixed absorbance of 1.8 for the main aza-BODIPY spectral band and a laser pulse input energy of 42 μJ. Higher second-order hyperpolarizability (γ) values were obtained for iodinated dyes 1, 2, 3 and 4. The highest value of 3.15×10−29 esu was obtained for 1. A comparative study involving the four non-iodinated dyes 1, 2, 3 and 4 and seven 1,3,5,7-tetraaryl aza-BODIPY dyes reported previously in the PhD thesis of Gugu Kubheka at Rhodes University demonstrated that there was no clear trend correlation between the γ values calculated from the Z-scan measurements and calculated dipole moments. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Molupe, Nthabeleng Regina
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466603 , vital:76758 , DOI https://doi.org/10.21504/10962/466603
- Description: New aza-BODIPY dyes and porphyrins were synthesised and characterised so that photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) activity studies could be performed. Several strategies were explored to achieve targeted nanoplatforms or biocompatible nanoplatforms to enhance the suitability of these compounds for use in PDT. Following earlier MSc research on the encapsulation of halogenated boron dipyrromethene (BODIPY) dyes into Pluronic® micelles, similar nanomicelles were prepared to encapsulate halogenated boron aza-dipyrromethene (aza-BODPY) dyes to enhance their aqueous solubility. However, the 1,7-dimethylthiophenyl- 2,6-diiodo-3,5-diphenyl (1) and 1,7-di-methylthiophenyl-2,6-diiodo- 3,5-dithien-3-yl (2) aza-BODIPY dyes that were prepared in this context were found to degrade when encapsulated. A different strategy was then followed in which gold nanoparticles (AuNPs) were conjugated to 1 and 2 via Au-S interactions to form biocompatible aza-BODIPY-AuNP conjugates (1-AuNP and 2-AuNP). This strategy was successful, and favourable IC50 values of 3.60 and 10.0 μM for 1-AuNP and 2- AuNP were obtained during in vitro PDT activity studies against MCF-7 human breast cancer cells, respectively, while values of 11.0 and 12.8 μM were obtained for 1 and 2. To further explore the preparation of better-targeted aza-BODIPY photosensitiser dyes, folic acid (FA) was conjugated to 1,7-dihydroxyphenyl-2,6-diiodo-3,5-di-4- bromophenyl (3) and 1,7-di-4-bromo-2,6-diiodo-3,5-dihydroxyphenylphenyl (4) aza- BODIPYs via ester bonds. Not only was the conjugation to form 3-FA and 4-FA successful, but the conjugated dyes are water-soluble, which is advantageous for drug transport in the context of PDT. These conjugates were applied in vitro against MCF-7 cancer cells and were found to have relatively high activities with IC50 values of 0.91 and 7.48 μM for 3-FA and 4-FA, respectively, while values of 11.3 and 13.0 μM were obtained for the non-conjugated 3 and 4 dyes. In a similar manner, tin (IV) and indium (III) tetrapyridylporphyrins (5 and 6) were axially conjugated to folic acid via ester bonds (5-FA and 6-FA). The conjugation was successful and enhanced the PDT activities of the dyes MCF-7 cancer cells in vitro from 48.2 to 29.6 μM for 5 and 5-FA, and from 43.9 to 13.3 μM for 6 and 6-FA. Relatively high dark toxicity was observed for 6-FA of 26.1 μM. When the nitrogen atoms of the meso-pyridyl rings were quaternized (5-FAQ and 6-FAQ) to further enhance the aqueous solubility of the complexes, it was not possible to calculate an IC50 value. When octanol-water partition coefficients (Log P) were calculated by the shake flask method, values of −0.70 and −1.70 were obtained for 5-FAQ and 6-FAQ, respectively. This provides evidence that the dyes are too water-soluble and not sufficiently lipophilic. The PACT activity properties of the synthesised diiodinated aza-BODIPYs were studied against Staphylococcus aureus (S. aureus) through photoirradiation for 60 min with Thorlabs M660L4 (280 mW.cm−2) and M730L4 (160 mW.cm−2) light emitting diodes (LEDs) mounted on the illumination chamber of Modulight® 7710-680 medical laser system providing doses at the well-plate of 100 and 57 J.cm−2.min−1. Aza- BODIPYs 2, 3 and 4 all inhibited the growth of S. aureus but with relatively low Log10 reductions of 1.37, 1.20 and 0.20. In contrast, aza-BODIPY 1 was found to have a Log10 reduction of 7.82. The PACT activities of free base and Sn(IV) 5-[4-(3- bromoethylcarboxyamidyl)phenyl]-10,15,20-triphenylporphyrins (7 and 8) prepared by Dr Balaji Babu (New Journal of Chemistry 2022, 46, 5288-5295) were tested against S. aureus to determine whether adding a triphenylphosphonium moiety to form free base and Sn(IV) 5-[4-(triphenylphosphonium)ethylcarboxyamidyl)phenyl]-10,15,20- triphenylporphyrin (18 and 19) enhances the photo-induced antibacterial activity, in addition to optimising the PDT properties due to its mitochondria-targeting properties. The PACT activities obtained against S. aureus were not favourable, but 18 exhibited enhanced activity across the studied concentration range. The potential utility of aza-BODIPY dyes 1-4 and their non-iodinated analogues (1a- 4a) for optical limiting applications was analysed by carrying out a series of Z-scan measurements, since dyes of this type have large ground state dipole moments, and this can enhance the non-linear optical limiting response. All the aza-BODIPY dyes under investigation exhibited intense non-linear absorption (NLA) behaviour with Zscan profiles that contain significant reverse saturable absorption (RSA) responses. Aza-BODIPYs 1, 2a, 2, 3, 4a, and 4 decreased the transmitted intensity of the strong laser beam to less than 50% of the linear response in organic solutions with a fixed absorbance of 1.8 for the main aza-BODIPY spectral band and a laser pulse input energy of 42 μJ. Higher second-order hyperpolarizability (γ) values were obtained for iodinated dyes 1, 2, 3 and 4. The highest value of 3.15×10−29 esu was obtained for 1. A comparative study involving the four non-iodinated dyes 1, 2, 3 and 4 and seven 1,3,5,7-tetraaryl aza-BODIPY dyes reported previously in the PhD thesis of Gugu Kubheka at Rhodes University demonstrated that there was no clear trend correlation between the γ values calculated from the Z-scan measurements and calculated dipole moments. , Thesis (PhD) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
Photodynamic anticancer and antimicrobial activities of novel bacteriochlorins
- Tauyakhale, Kaisano Goodness
- Authors: Tauyakhale, Kaisano Goodness
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464587 , vital:76524
- Description: The World Health Organization cautioned that the major contributing factors of cancer amongst people are the excessive usage of alcohol, smoking, lack of exercise and low intake of fruits, vegetables, and high-fibre foods. Furthermore, cancer by far is reported to be the most common and leading cause of death worldwide (1 in 6 deaths is due to cancer). Moreover, it is reported that cancer kills more people than tuberculosis, malaria and AIDS combined every year. Chemotherapy has been utilised as a mode of rehabilitation for complete being used in conjunction with surgery or to improve the state of well-being of patients until their point of death. However, it is well known for its adverse effects, such as loss of hair, altered gastric metabolism, vomiting and nausea, dehydration, weight loss, and loss of appetite. For this reason, photodynamic therapy (PDT) was developed as an alternative. A molecular dye (photosensitiser/PS) and light of a specific wavelength produce cytotoxic singlet oxygen species, which induce cell death. The aim of this project is to prepare novel structurally modified porphyrin-type dyes that absorb far into the near-infrared region. Identifying suitable dyes that absorb significantly in the 700−800 nm region is particularly important from an African perspective, since melanin significantly limits the penetration of laser light into human tissue in the 600−700 nm region, where first- and second-generation photosensitiser dyes usually absorb. The porphyrin analogues that will be investigated in this regard are bacteriochlorins (BChls), which are known to have suitable optical properties that are potentially suitable in this regard. The first step of the study would be to synthesise tetraarylporphyrins with electron- withdrawing meso-aryl rings because their reduction to BChls is more readily attainable than is the case with electron-donating rings. However, these contrasting properties can be combined to tailor the BChls for effective photodynamic therapy, so the type of porphyrins synthesised will be tetraarylBChls with different meso-aryl groups to first analyze the induction of different chemical properties in this case, the impact of introducing electron donating (4- and 3-quinoline substituents) or electron-withdrawing (pentafluorophenyl substituents) groups on the meso-positions of the dyes and more specifically whether the position of the quinoline nitrogen atom relative to the core of the BChl has any significant impact on the reactivity of the dye (the 4- or 3-position of the quinoline). The next factor to be considered is the induction of the heavy atom effect by introducing a metal in the centre of the dye in order to try to increase the singlet oxygen quantum yields for high production of reactive oxygen species and singlet oxygen and further red shift the lowest energy absorption band of the BChls in the therapeutic window for deep tissue penetration for effective. Lastly, the goal will be to explore whether the delivery of bacteriochlorin photosensitisers to cancer cells can be enhanced by introducing quaternised nitrogen atoms to the meso-aryl ligands. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Tauyakhale, Kaisano Goodness
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464587 , vital:76524
- Description: The World Health Organization cautioned that the major contributing factors of cancer amongst people are the excessive usage of alcohol, smoking, lack of exercise and low intake of fruits, vegetables, and high-fibre foods. Furthermore, cancer by far is reported to be the most common and leading cause of death worldwide (1 in 6 deaths is due to cancer). Moreover, it is reported that cancer kills more people than tuberculosis, malaria and AIDS combined every year. Chemotherapy has been utilised as a mode of rehabilitation for complete being used in conjunction with surgery or to improve the state of well-being of patients until their point of death. However, it is well known for its adverse effects, such as loss of hair, altered gastric metabolism, vomiting and nausea, dehydration, weight loss, and loss of appetite. For this reason, photodynamic therapy (PDT) was developed as an alternative. A molecular dye (photosensitiser/PS) and light of a specific wavelength produce cytotoxic singlet oxygen species, which induce cell death. The aim of this project is to prepare novel structurally modified porphyrin-type dyes that absorb far into the near-infrared region. Identifying suitable dyes that absorb significantly in the 700−800 nm region is particularly important from an African perspective, since melanin significantly limits the penetration of laser light into human tissue in the 600−700 nm region, where first- and second-generation photosensitiser dyes usually absorb. The porphyrin analogues that will be investigated in this regard are bacteriochlorins (BChls), which are known to have suitable optical properties that are potentially suitable in this regard. The first step of the study would be to synthesise tetraarylporphyrins with electron- withdrawing meso-aryl rings because their reduction to BChls is more readily attainable than is the case with electron-donating rings. However, these contrasting properties can be combined to tailor the BChls for effective photodynamic therapy, so the type of porphyrins synthesised will be tetraarylBChls with different meso-aryl groups to first analyze the induction of different chemical properties in this case, the impact of introducing electron donating (4- and 3-quinoline substituents) or electron-withdrawing (pentafluorophenyl substituents) groups on the meso-positions of the dyes and more specifically whether the position of the quinoline nitrogen atom relative to the core of the BChl has any significant impact on the reactivity of the dye (the 4- or 3-position of the quinoline). The next factor to be considered is the induction of the heavy atom effect by introducing a metal in the centre of the dye in order to try to increase the singlet oxygen quantum yields for high production of reactive oxygen species and singlet oxygen and further red shift the lowest energy absorption band of the BChls in the therapeutic window for deep tissue penetration for effective. Lastly, the goal will be to explore whether the delivery of bacteriochlorin photosensitisers to cancer cells can be enhanced by introducing quaternised nitrogen atoms to the meso-aryl ligands. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Date Issued: 2024-10-11
Platform food delivery: a study on the labour process and emotional labour experienced by gig workers in the Eastern Cape food delivery sector
- Authors: Mutshewa, Taboka Botsang
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466221 , vital:76708
- Description: As central to the gig economy, digital platforms are transforming the character of the modern economy. South Africa has seen the increased use of technology and the integration of technological changes into the labour market and labour process, including via digital platforms. The gig economy has entered a range of economic sectors in South Africa and elsewhere, including the service sector. Examples of digital platforms in this specific sector include Uber and Bolt for transportation, Sweep South for domestic help, and Mr D Food for food delivery. Undoubtedly, by inhibiting and sanctioning movements globally and locally, the COVID-19 pandemic contributed to the expansion of the gig economy in the service sector, as it restricted walk-in customers. The digital platform mediates the relationship between service sector workers and their clients and between workers and the companies operating the platforms. In this way, these technological platforms act as an ‘extra hand’ by, for example, hiring delivery workers in the first instance and then facilitating the delivery of products to customers. This thesis examines the food delivery sector in the gig economy in the Eastern Cape Province of South Africa. The digital platforms in the food sector allow consumers to place food orders at a restaurant of choice and deliver them to their doorstep in less than an hour, ensuring convenience, reliability and efficiency for restaurants and customers. However, understanding the gig economy involves identifying and unpacking the experiences and perspectives of the gig workers. In doing so, this thesis examines food delivery workers labouring for two different companies (Uber East and Mr D Foods) in two sites (Makhanda and Gqeberha). The main aim is to analyse how the digital platforms restructure the labour process in the gig economy and the emotional labour enacted by the delivery workers. The thesis draws upon labour process and emotional labour theory to pursue this primary aim. Research findings highlight a high level of precariousness and stress amongst food delivery workers as they work under algorithmic systems of labour control marked by surveillance and are constantly required to perform emotionally to maximise income. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Mutshewa, Taboka Botsang
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/466221 , vital:76708
- Description: As central to the gig economy, digital platforms are transforming the character of the modern economy. South Africa has seen the increased use of technology and the integration of technological changes into the labour market and labour process, including via digital platforms. The gig economy has entered a range of economic sectors in South Africa and elsewhere, including the service sector. Examples of digital platforms in this specific sector include Uber and Bolt for transportation, Sweep South for domestic help, and Mr D Food for food delivery. Undoubtedly, by inhibiting and sanctioning movements globally and locally, the COVID-19 pandemic contributed to the expansion of the gig economy in the service sector, as it restricted walk-in customers. The digital platform mediates the relationship between service sector workers and their clients and between workers and the companies operating the platforms. In this way, these technological platforms act as an ‘extra hand’ by, for example, hiring delivery workers in the first instance and then facilitating the delivery of products to customers. This thesis examines the food delivery sector in the gig economy in the Eastern Cape Province of South Africa. The digital platforms in the food sector allow consumers to place food orders at a restaurant of choice and deliver them to their doorstep in less than an hour, ensuring convenience, reliability and efficiency for restaurants and customers. However, understanding the gig economy involves identifying and unpacking the experiences and perspectives of the gig workers. In doing so, this thesis examines food delivery workers labouring for two different companies (Uber East and Mr D Foods) in two sites (Makhanda and Gqeberha). The main aim is to analyse how the digital platforms restructure the labour process in the gig economy and the emotional labour enacted by the delivery workers. The thesis draws upon labour process and emotional labour theory to pursue this primary aim. Research findings highlight a high level of precariousness and stress amongst food delivery workers as they work under algorithmic systems of labour control marked by surveillance and are constantly required to perform emotionally to maximise income. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
Post migration factors associated with elevated symptoms of posttraumatic stress disorder, depression, and anxiety, among refugees in Cape Town
- Authors: Mujuru, Agnes
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465810 , vital:76655
- Description: There has been a heavy influx of refugees in South Africa due to wars, conflicts, political persecution, and economic recessions around the world. As a result, South Africa hosts the highest number of African refugees, who are susceptible to mental health problems because of their exposure to war, violence, and post migration stressors. The current study assessed post migration predictors of post-traumatic stress disorder (PTSD), depression and anxiety symptoms among refugees in Cape Town South Africa. A cross-sectional survey of refugees from war- and conflict-torn countries settled in Cape Town was conducted between February and May 2023. Study participants (N = 147) were selected using respondent driven sampling technique. Data were collected using a questionnaire made up of the Post-traumatic Stress Disorder Checklist (PCL-5), Patient Health Questionnaire (PHQ-9), Generalised Anxiety Disorder-7 (GAD-7), and the Post- Migration Difficulties Checklist (PMLDs), to assess PTSD, depression, anxiety and PMLDs, respectively. Descriptive and inferential statistics were used to analyse the questionnaire data. The prevalence of PTSD, anxiety and depression symptoms was 26.5%, 33.3% and 33.3%, respectively. Regression analyses identified discrimination, poor access to health services, and poor access to food as the major predictors of common mental disorders among refugees. The document-seeking process, unemployment stress, language difficulties, not getting help with welfare, fears of being sent home and isolation, were also associated with symptoms of mental health conditions. These results suggest that psychological distress symptoms are highly elevated among refugees and are associated with post-migration stressors. Mental health interventions for refugees should not only address psychological difficulties but also consider the socio-economic needs of refugees. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Mujuru, Agnes
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/465810 , vital:76655
- Description: There has been a heavy influx of refugees in South Africa due to wars, conflicts, political persecution, and economic recessions around the world. As a result, South Africa hosts the highest number of African refugees, who are susceptible to mental health problems because of their exposure to war, violence, and post migration stressors. The current study assessed post migration predictors of post-traumatic stress disorder (PTSD), depression and anxiety symptoms among refugees in Cape Town South Africa. A cross-sectional survey of refugees from war- and conflict-torn countries settled in Cape Town was conducted between February and May 2023. Study participants (N = 147) were selected using respondent driven sampling technique. Data were collected using a questionnaire made up of the Post-traumatic Stress Disorder Checklist (PCL-5), Patient Health Questionnaire (PHQ-9), Generalised Anxiety Disorder-7 (GAD-7), and the Post- Migration Difficulties Checklist (PMLDs), to assess PTSD, depression, anxiety and PMLDs, respectively. Descriptive and inferential statistics were used to analyse the questionnaire data. The prevalence of PTSD, anxiety and depression symptoms was 26.5%, 33.3% and 33.3%, respectively. Regression analyses identified discrimination, poor access to health services, and poor access to food as the major predictors of common mental disorders among refugees. The document-seeking process, unemployment stress, language difficulties, not getting help with welfare, fears of being sent home and isolation, were also associated with symptoms of mental health conditions. These results suggest that psychological distress symptoms are highly elevated among refugees and are associated with post-migration stressors. Mental health interventions for refugees should not only address psychological difficulties but also consider the socio-economic needs of refugees. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-10-11
Potential futures: land management decision making in the Albertinia-Herbertsdale area of the Gouritz Cluster Biosphere Reserve
- Johnson, Ryana Elizabeth Milne
- Authors: Johnson, Ryana Elizabeth Milne
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464823 , vital:76548
- Description: Land use change drives biodiversity losses, and UNESCO biosphere reserves serve as laboratories for solving complex problems in the uncertain Anthropocene geological era. Land users' decisions form turning points for land use, biodiversity conservation and future trajectories of land management. This qualitative study used grounded theory, one-on-one interviews and a futures thinking workshop to explore land user decision making in the mixed agricultural Herbertsdale- Albertinia area of the Gouritz Cluster Biosphere Reserve. The study included participants using a variety of land management approaches, ranging from conservation to intensive agriculture. This study found that land managers in the study area interact with multiple complex social-ecological systems, and land management outcomes can be unpredictable for diverse reasons. Informed by learning and risk mitigation as well as their motivation for their present and future, land users are integrating sustainable land management practices in their commercial land management decisions. Their risk adaptation strategies tend to be hands on, independent and practical, as well as action oriented. This can be limiting when adaptation requires abstract, collective or systemic changes. All the participants know that they are dependent on natural resources. They all value their community and social networks. They have a strong appetite for learning, and combine an understanding of the historical context of their land management with an understanding that positive futures will require dynamic and extensive changes at multiple scales. They desire more integrated land use planning at catchment and landscape scales. Collaboration and collaborative strategies emerged as important pathways to the desired future. These include landscape level planning, lobbying for political and legal change, building community, learning, sustainable land management and social integration. It emerged that giving people time to think about abstract or large scale issues is appreciated, and not currently routine. This provides a potential leverage point for collaborative environmental stewardship in this highly biodiverse region. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Johnson, Ryana Elizabeth Milne
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464823 , vital:76548
- Description: Land use change drives biodiversity losses, and UNESCO biosphere reserves serve as laboratories for solving complex problems in the uncertain Anthropocene geological era. Land users' decisions form turning points for land use, biodiversity conservation and future trajectories of land management. This qualitative study used grounded theory, one-on-one interviews and a futures thinking workshop to explore land user decision making in the mixed agricultural Herbertsdale- Albertinia area of the Gouritz Cluster Biosphere Reserve. The study included participants using a variety of land management approaches, ranging from conservation to intensive agriculture. This study found that land managers in the study area interact with multiple complex social-ecological systems, and land management outcomes can be unpredictable for diverse reasons. Informed by learning and risk mitigation as well as their motivation for their present and future, land users are integrating sustainable land management practices in their commercial land management decisions. Their risk adaptation strategies tend to be hands on, independent and practical, as well as action oriented. This can be limiting when adaptation requires abstract, collective or systemic changes. All the participants know that they are dependent on natural resources. They all value their community and social networks. They have a strong appetite for learning, and combine an understanding of the historical context of their land management with an understanding that positive futures will require dynamic and extensive changes at multiple scales. They desire more integrated land use planning at catchment and landscape scales. Collaboration and collaborative strategies emerged as important pathways to the desired future. These include landscape level planning, lobbying for political and legal change, building community, learning, sustainable land management and social integration. It emerged that giving people time to think about abstract or large scale issues is appreciated, and not currently routine. This provides a potential leverage point for collaborative environmental stewardship in this highly biodiverse region. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2024
- Full Text:
- Date Issued: 2024-10-11
Promoting Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology in Oshakati education circuit
- Authors: Angula, Mechtilde
- Date: 2024-10-11
- Subjects: Algebra Study and teaching (Secondary) Namibia Oshakati , Technological Pedagogical Content Knowledge , Educational technology , Education Social aspects Namibia , Culturally relevant pedagogy Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463669 , vital:76430
- Description: The revised curriculum in Namibia highlights the integration of digital tools to help learners understand mathematics better. For this purpose, teachers need to possess Technological Pedagogical Content Knowledge (TPACK) to utilize technology effectively. However, using technology by itself does not guarantee better learning rather, it requires an understanding of how to integrate technology in teaching mathematics. Therefore, this case study explored Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology. An interpretive paradigm, supported by a pragmatic paradigm, underpins the study, and a qualitative case study approach was employed. The study purposively engaged ten Grade 9 mathematics teachers from four schools in Namibia. Demographic questionnaires, Semi-structured interviews, Reflective journals, notes from discussions, focus group interviews and document analysis were used to gain teachers’ insights on TPACK development. The study was guided by two educational theories: Bernstein's Sociology of Education (1971) and Bloom's Taxonomy of the Cognitive Domain (1956). Also, Mishra and Koehler’s TPACK framework (2009) was used to analyze the data. The findings showed that mathematics teachers had a positive view of technology integration in mathematics lessons and TPACK development through technology-integrated lesson planning, but they lacked the knowledge for planning lessons that integrate technology. Taking part in the intervention improved the selected mathematics teachers' understanding of TPACK, making them more confident about using technology in their teaching. The study also found different strategies to help teachers incorporate technology into their lessons, along with having a strong grasp of the subject and effective teaching methods. Based on these findings, it is suggested that in-service mathematics teachers take part in interventions focused on integrating technology into lesson planning. These interventions should demonstrate how technology can improve mathematics education and how it fits with both content and teaching methods. It is also recommended that these interventions emphasize the importance of Bloom's Taxonomy in using technology for mathematics education. The study concludes by suggesting further research on how planned lessons can be implemented in actual mathematics classrooms. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Angula, Mechtilde
- Date: 2024-10-11
- Subjects: Algebra Study and teaching (Secondary) Namibia Oshakati , Technological Pedagogical Content Knowledge , Educational technology , Education Social aspects Namibia , Culturally relevant pedagogy Namibia
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463669 , vital:76430
- Description: The revised curriculum in Namibia highlights the integration of digital tools to help learners understand mathematics better. For this purpose, teachers need to possess Technological Pedagogical Content Knowledge (TPACK) to utilize technology effectively. However, using technology by itself does not guarantee better learning rather, it requires an understanding of how to integrate technology in teaching mathematics. Therefore, this case study explored Grade 9 mathematics teachers’ TPACK development through planning algebra lessons that integrate technology. An interpretive paradigm, supported by a pragmatic paradigm, underpins the study, and a qualitative case study approach was employed. The study purposively engaged ten Grade 9 mathematics teachers from four schools in Namibia. Demographic questionnaires, Semi-structured interviews, Reflective journals, notes from discussions, focus group interviews and document analysis were used to gain teachers’ insights on TPACK development. The study was guided by two educational theories: Bernstein's Sociology of Education (1971) and Bloom's Taxonomy of the Cognitive Domain (1956). Also, Mishra and Koehler’s TPACK framework (2009) was used to analyze the data. The findings showed that mathematics teachers had a positive view of technology integration in mathematics lessons and TPACK development through technology-integrated lesson planning, but they lacked the knowledge for planning lessons that integrate technology. Taking part in the intervention improved the selected mathematics teachers' understanding of TPACK, making them more confident about using technology in their teaching. The study also found different strategies to help teachers incorporate technology into their lessons, along with having a strong grasp of the subject and effective teaching methods. Based on these findings, it is suggested that in-service mathematics teachers take part in interventions focused on integrating technology into lesson planning. These interventions should demonstrate how technology can improve mathematics education and how it fits with both content and teaching methods. It is also recommended that these interventions emphasize the importance of Bloom's Taxonomy in using technology for mathematics education. The study concludes by suggesting further research on how planned lessons can be implemented in actual mathematics classrooms. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Date Issued: 2024-10-11
Protecting and organising the apartheid and post-apartheid precarious municipal workforce: the Cape Town Municipal Workers Association and the South African Municipal Workers Union in Cape Town
- Authors: Mathekga, Jerry Mmanoko
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/467072 , vital:76812 , DOI https://doi.org/10.21504/10962/467072
- Description: The contemporary, global expansion of precarious employment poses key challenges for unions based on workers in full-time, stable employment (i.e. workers in the so-called “Standard Employment Relationship” – SER). South African unions and federations like the Congress of South African Trade Unions (COSATU), have resolved to organise these workers for decades. Most unions have, however done little to put these intentions into effect, even though precarity threatens union survival. A notable exception amongst unions in both the state and private sectors is COSATU’s South African Municipal Workers Union (SAMWU). SAMWU has a long history of consistently acting to protect and organise precarious workers. This is the puzzle with which this thesis grapples: why has SAMWU been different? This question is examined through a focus on Cape Town, the city in which the union has the deepest roots: its main, immediate predecessor, the Cape Town Municipal Workers Association (CTMWA), was founded in Cape Town in 1918. Answering the question posed above requires examining the record: how has SAMWU – and before it, the CTMWA – protected and organise precarious workers in the municipal sector over time? And further, why did CTMWA and SAMWU act this way, when many others have not? The answers lie in the distinctive character of the organisation’s trade union identity, drawing on Richard Hyman’s work, which moves beyond broad labels (business unionism, political unionism, etc.) and normative prescriptions (what unions should, ideally, do) to develop a nuanced model of what predisposes, and enables, certain union choices, actions, and responses union. The popular power resources approach (PRA) to unions helps map the resources available to unions but cannot explain why unions use power resources in specific ways. The thesis argues that the evolving union identity of the CTMWA and SAMWU predisposed it to organising workers, and that this evolving identity has been shaped by the distinctive features of the Western Cape and its political traditions, a long history of multiple municipal labour markets in Cape Town, and the specificities of that city, including the black African / Coloured division, its independent left traditions, the relative weakness of the COSATU’s allies, the African National Congress (ANC) and the South African Communist Party (SACP), in local government, and the peculiar dynamics of municipal restructuring. This thesis draws on both labour history and industrial Sociology, arguing that a dialogue between these two disciplines enriches labour studies. This thesis draws on a wide range of primary sources, both historical and contemporary, examines historical processes and change, and engages in a dialogue between historical and sociological work. It argues for the need to historicise precarity, avoiding a “year zero” approach that treats it as a novel challenge for unions, and as reducible to neo-liberalism. It insists that labour responses are shaped by place and time, and so, for the need to balance macro-level discussions of trends with local specificities. It argues that notion of a sharp rupture between the surging new wave of unionism that started in South Africa in 1973, from which COSATU emerged, and the older traditions of registered unionism has been overstated. More attention needs to be paid to the imprint of the more radical registered unions, like CTMWA, on the new unionism. Rejecting pessimistic accounts that see unions as doomed by precarity, it draws attention to long histories of relatively successful and sustained union responses, like those of CTMWA/ SAMWU. However, it questions prescriptive approaches that centre on what unions should do, highlighting how evolving union identity shapes what unions can do. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Mathekga, Jerry Mmanoko
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/467072 , vital:76812 , DOI https://doi.org/10.21504/10962/467072
- Description: The contemporary, global expansion of precarious employment poses key challenges for unions based on workers in full-time, stable employment (i.e. workers in the so-called “Standard Employment Relationship” – SER). South African unions and federations like the Congress of South African Trade Unions (COSATU), have resolved to organise these workers for decades. Most unions have, however done little to put these intentions into effect, even though precarity threatens union survival. A notable exception amongst unions in both the state and private sectors is COSATU’s South African Municipal Workers Union (SAMWU). SAMWU has a long history of consistently acting to protect and organise precarious workers. This is the puzzle with which this thesis grapples: why has SAMWU been different? This question is examined through a focus on Cape Town, the city in which the union has the deepest roots: its main, immediate predecessor, the Cape Town Municipal Workers Association (CTMWA), was founded in Cape Town in 1918. Answering the question posed above requires examining the record: how has SAMWU – and before it, the CTMWA – protected and organise precarious workers in the municipal sector over time? And further, why did CTMWA and SAMWU act this way, when many others have not? The answers lie in the distinctive character of the organisation’s trade union identity, drawing on Richard Hyman’s work, which moves beyond broad labels (business unionism, political unionism, etc.) and normative prescriptions (what unions should, ideally, do) to develop a nuanced model of what predisposes, and enables, certain union choices, actions, and responses union. The popular power resources approach (PRA) to unions helps map the resources available to unions but cannot explain why unions use power resources in specific ways. The thesis argues that the evolving union identity of the CTMWA and SAMWU predisposed it to organising workers, and that this evolving identity has been shaped by the distinctive features of the Western Cape and its political traditions, a long history of multiple municipal labour markets in Cape Town, and the specificities of that city, including the black African / Coloured division, its independent left traditions, the relative weakness of the COSATU’s allies, the African National Congress (ANC) and the South African Communist Party (SACP), in local government, and the peculiar dynamics of municipal restructuring. This thesis draws on both labour history and industrial Sociology, arguing that a dialogue between these two disciplines enriches labour studies. This thesis draws on a wide range of primary sources, both historical and contemporary, examines historical processes and change, and engages in a dialogue between historical and sociological work. It argues for the need to historicise precarity, avoiding a “year zero” approach that treats it as a novel challenge for unions, and as reducible to neo-liberalism. It insists that labour responses are shaped by place and time, and so, for the need to balance macro-level discussions of trends with local specificities. It argues that notion of a sharp rupture between the surging new wave of unionism that started in South Africa in 1973, from which COSATU emerged, and the older traditions of registered unionism has been overstated. More attention needs to be paid to the imprint of the more radical registered unions, like CTMWA, on the new unionism. Rejecting pessimistic accounts that see unions as doomed by precarity, it draws attention to long histories of relatively successful and sustained union responses, like those of CTMWA/ SAMWU. However, it questions prescriptive approaches that centre on what unions should do, highlighting how evolving union identity shapes what unions can do. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2024
- Full Text:
- Date Issued: 2024-10-11
Protecting stateless children in South Africa through nationality: a children’s rights approach
- Authors: Maziya, Nokwanda Takalanga
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466469 , vital:76733 , DOI https://doi.org/10.21504/10962/466469
- Description: This study investigates the role of nationality in protecting stateless children. Under interna-tional human rights law, all individuals, including stateless persons, are entitled to certain rights by virtue of being human. Consequently, stateless children should theoretically have access to fundamental rights such as education, healthcare, and social security, even without nationality. However, this study challenges the assumption that stateless children can access these rights merely because they are human. The study reveals that, in practice, stateless chil-dren struggle to access essential rights like education, healthcare, and social welfare without nationality. The study asserts that nationality is crucial for stateless children to access basic rights in South Africa. The study examines various treaties related to nationality and con-cludes that none impose a binding obligation on South Africa to confer nationality on state-less children. The study then draws on international children's rights principles such as the best interest of the child, the right to life, survival and development, and the right to non-discrimination to demonstrate that despite a clear obligation on South Africa in terms of trea-ty law to grant nationality to stateless, these principles, place limits on South Africa's exer-cise of sovereign power. This, in turn, makes way for granting nationality to stateless chil-dren. , Thesis (PhD) -- Faculty of Law, Law, 2024
- Full Text:
- Date Issued: 2024-10-11
- Authors: Maziya, Nokwanda Takalanga
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/466469 , vital:76733 , DOI https://doi.org/10.21504/10962/466469
- Description: This study investigates the role of nationality in protecting stateless children. Under interna-tional human rights law, all individuals, including stateless persons, are entitled to certain rights by virtue of being human. Consequently, stateless children should theoretically have access to fundamental rights such as education, healthcare, and social security, even without nationality. However, this study challenges the assumption that stateless children can access these rights merely because they are human. The study reveals that, in practice, stateless chil-dren struggle to access essential rights like education, healthcare, and social welfare without nationality. The study asserts that nationality is crucial for stateless children to access basic rights in South Africa. The study examines various treaties related to nationality and con-cludes that none impose a binding obligation on South Africa to confer nationality on state-less children. The study then draws on international children's rights principles such as the best interest of the child, the right to life, survival and development, and the right to non-discrimination to demonstrate that despite a clear obligation on South Africa in terms of trea-ty law to grant nationality to stateless, these principles, place limits on South Africa's exer-cise of sovereign power. This, in turn, makes way for granting nationality to stateless chil-dren. , Thesis (PhD) -- Faculty of Law, Law, 2024
- Full Text:
- Date Issued: 2024-10-11