Chemostratigraphy of the lowermost iron-manganese cycle of the Hotazel Formation, and implications for its primary depositional environment
- Authors: Masoabi, Ntseka Thomas
- Date: 2022-10-14
- Subjects: Chemostratigraphy , Great Oxygenation Event , Manganese ores Geology South Africa Northern Cape , Banded iron formation
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362938 , vital:65376
- Description: The giant Kalahari Manganese Field (KMF), located in the Northern Cape Province, South Africa, comprises approximately half of the world’s manganese resources, estimated at about eight billion tons at grades ranging from 20-48 wt%. The KMF is linked to a period in geological time when the Earth’s atmospheric and oceanic conditions underwent a major transition from oxygen-deficient to oxygen-enriched conditions – an event famously referred to as the Great Oxidation Event (GOE) that occurred around 2.4 Ga. The KMF deposits are hosted in Banded Iron Formation (BIF) of the Paleoproterozoic Hotazel Formation in the uppermost Transvaal Supergroup. The sedimentary Mn ores are interbedded with Hotazel BIF in the form of three alternating depositional cycles of BIF, transitional hematite lutite and laminated, carbonate-rich manganese ore. The lowermost and thickest of the three cycles is the most economically significant and has been mined for several decades on a large scale from the southernmost KMF. In this study, two drill cores from the southern KMF were inspected, logged and sampled at a high resolution of approximately half-meter interval per sample. The selected cores, namely G774, capturing the lower portion of the Hotazel Formation from the Mamatwan locality, and MP-56, capturing the corresponding portion from the Middleplaats locality, are geographically proximal to each other, with a horizontal distance of roughly 3 km separating the two of them. The G774 drill core is characterized by a conspicuously thick manganese layer covering a thickness of 50 m, with the overlying BIF reaching a total thickness of 11 m. The MP-56 drill core, on the other hand, has a relatively thinner corresponding manganese layer of 30 m in thickness, while the overlying BIF layer exhibits a thickness of 24 m. The extent of sampling up-section was constrained by an apparently coeval black shale layer which represents the chosen upper stratigraphic marker for the lower part of the Hotazel section in the broader area that is under investigation in this thesis. That way, a high resolution chemostratigraphic approach was employed to elucidate the potential factors contributing to the relative sedimentary lateral thickness variations seen across the southernmost KMF. High-resolution geochemical data were used to explore relationships and signals that might constrain relative precipitation rates for iron and manganese against detrital species, fluctuating redox conditions in the original environment of deposition, and chemostratigraphic correlation. All geochemical data (i.e., major oxides, minor and trace elements and carbonate carbon isotopes) were obtained respectively through employing X-ray Fluorescence (XRF), Laser Ablation Inductively Coupled Mass Spectrometry (ICP-MS), and Gas-source mass spectrometry. Comparative considerations made between the bulk geochemistry of the two sequences (i.e., Mamatwan and Middleplaats sections) reveal that periods of high-Mn deposition in the Hotazel Formation appear to be very Ca-carbonate rich (as indicated by high CaO, LOI and Sr concentrations). This, in turn, suggests that the Mn abundance is in the Hotazel ores is controlled mainly by the silicate phase braunite and is diluted by the deposition of Ca-carbonate through time. Bulk-rock concentration results for trace elements of the High Field Strength Element (HFSE) group (namely Zr, Hf, Y, Nb and Sc) were utilized to constrain the rates of either clastic and/or volcanic detrital inputs, as they traditionally represent refractory mineral particles of a common detrital/volcanic origin. The two chemosedimentary sequences preserve these elements in very low and thus quantitatively negligible concentrations – suggesting that the Hotazel depositional environment received very low and insignificant influx of a terrigeneous detrital component. A selection of these elements was therefore used to deduce, with caution, the relative as opposed to absolute precipitation rate of the major chemical constituents (i.e., Fe + Si vs Mn + carbonate), assuming a constant detrital flux through time. It was found that the relative abundances of Zr, Y and Nb is roughly 1.5 – 2 times as high in the BIF lithofacies relative to the Mn ones at both localities. This led to the inference that the Mn-enriched portion of the sediment must have been deposited at approximately twice the rate that the Fe-rich (BIF) portion was originally deposited. In terms of redox-sensitive elements, the elements Co and Mo seem to reveal the most valuable insights into the redox environment of primary chemical deposition. Cobalt displays a unique pattern in that its highest concentration is attained at the hematite lutite transitions (similarly with the REE in this regard), while very low and seemingly invariant concentration is exhibited within the core of the main orebodies. The same pattern seems to be reproduced to a degree by the corresponding bulk MgO component, whereby MgO abundance maxima are associated with the basal hematite lutite and the hematitic flanks of the Mn-ore zone, while the core of the Mn-rich layer attains relatively low and essentially invariant MgO concentrations. This implicates a close and direct association of Co with the hematite fraction of the rocks and a concurrent enrichment in Mn-rich carbonate (dolomite). On the other hand, Mo seems to have a direct and clear association with peak MnO2 content of the rocks, which in turn presents a high possibility of Mo having adsorbed onto primary Mn-oxyhydroxides in the water column, thus providing evidence that Mn-oxide must have acted as an important Mo sink, at least locally. Finally, the carbonate-carbon isotope results provide a useful tool that brings the two stratigraphic sections “together“, in conjunction with other correlatable chemostratigraphic parameters (e.g. Co, Mg). The results demonstrate that bulk carbon fluxes and isotopic signals in the sediments must reflect primary processes of deposition, and that correlation across two apparently disparate lithostratigraphic sections can be effected. The key finding is that, at times, manganese deposition in one part of a vii stratified basin was evidently accompanied by simultaneous BIF deposition at another, thus painting a very complex picture of massive primary chemical precipitation of Fe and Mn at the dawn of the GOE. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Masoabi, Ntseka Thomas
- Date: 2022-10-14
- Subjects: Chemostratigraphy , Great Oxygenation Event , Manganese ores Geology South Africa Northern Cape , Banded iron formation
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362938 , vital:65376
- Description: The giant Kalahari Manganese Field (KMF), located in the Northern Cape Province, South Africa, comprises approximately half of the world’s manganese resources, estimated at about eight billion tons at grades ranging from 20-48 wt%. The KMF is linked to a period in geological time when the Earth’s atmospheric and oceanic conditions underwent a major transition from oxygen-deficient to oxygen-enriched conditions – an event famously referred to as the Great Oxidation Event (GOE) that occurred around 2.4 Ga. The KMF deposits are hosted in Banded Iron Formation (BIF) of the Paleoproterozoic Hotazel Formation in the uppermost Transvaal Supergroup. The sedimentary Mn ores are interbedded with Hotazel BIF in the form of three alternating depositional cycles of BIF, transitional hematite lutite and laminated, carbonate-rich manganese ore. The lowermost and thickest of the three cycles is the most economically significant and has been mined for several decades on a large scale from the southernmost KMF. In this study, two drill cores from the southern KMF were inspected, logged and sampled at a high resolution of approximately half-meter interval per sample. The selected cores, namely G774, capturing the lower portion of the Hotazel Formation from the Mamatwan locality, and MP-56, capturing the corresponding portion from the Middleplaats locality, are geographically proximal to each other, with a horizontal distance of roughly 3 km separating the two of them. The G774 drill core is characterized by a conspicuously thick manganese layer covering a thickness of 50 m, with the overlying BIF reaching a total thickness of 11 m. The MP-56 drill core, on the other hand, has a relatively thinner corresponding manganese layer of 30 m in thickness, while the overlying BIF layer exhibits a thickness of 24 m. The extent of sampling up-section was constrained by an apparently coeval black shale layer which represents the chosen upper stratigraphic marker for the lower part of the Hotazel section in the broader area that is under investigation in this thesis. That way, a high resolution chemostratigraphic approach was employed to elucidate the potential factors contributing to the relative sedimentary lateral thickness variations seen across the southernmost KMF. High-resolution geochemical data were used to explore relationships and signals that might constrain relative precipitation rates for iron and manganese against detrital species, fluctuating redox conditions in the original environment of deposition, and chemostratigraphic correlation. All geochemical data (i.e., major oxides, minor and trace elements and carbonate carbon isotopes) were obtained respectively through employing X-ray Fluorescence (XRF), Laser Ablation Inductively Coupled Mass Spectrometry (ICP-MS), and Gas-source mass spectrometry. Comparative considerations made between the bulk geochemistry of the two sequences (i.e., Mamatwan and Middleplaats sections) reveal that periods of high-Mn deposition in the Hotazel Formation appear to be very Ca-carbonate rich (as indicated by high CaO, LOI and Sr concentrations). This, in turn, suggests that the Mn abundance is in the Hotazel ores is controlled mainly by the silicate phase braunite and is diluted by the deposition of Ca-carbonate through time. Bulk-rock concentration results for trace elements of the High Field Strength Element (HFSE) group (namely Zr, Hf, Y, Nb and Sc) were utilized to constrain the rates of either clastic and/or volcanic detrital inputs, as they traditionally represent refractory mineral particles of a common detrital/volcanic origin. The two chemosedimentary sequences preserve these elements in very low and thus quantitatively negligible concentrations – suggesting that the Hotazel depositional environment received very low and insignificant influx of a terrigeneous detrital component. A selection of these elements was therefore used to deduce, with caution, the relative as opposed to absolute precipitation rate of the major chemical constituents (i.e., Fe + Si vs Mn + carbonate), assuming a constant detrital flux through time. It was found that the relative abundances of Zr, Y and Nb is roughly 1.5 – 2 times as high in the BIF lithofacies relative to the Mn ones at both localities. This led to the inference that the Mn-enriched portion of the sediment must have been deposited at approximately twice the rate that the Fe-rich (BIF) portion was originally deposited. In terms of redox-sensitive elements, the elements Co and Mo seem to reveal the most valuable insights into the redox environment of primary chemical deposition. Cobalt displays a unique pattern in that its highest concentration is attained at the hematite lutite transitions (similarly with the REE in this regard), while very low and seemingly invariant concentration is exhibited within the core of the main orebodies. The same pattern seems to be reproduced to a degree by the corresponding bulk MgO component, whereby MgO abundance maxima are associated with the basal hematite lutite and the hematitic flanks of the Mn-ore zone, while the core of the Mn-rich layer attains relatively low and essentially invariant MgO concentrations. This implicates a close and direct association of Co with the hematite fraction of the rocks and a concurrent enrichment in Mn-rich carbonate (dolomite). On the other hand, Mo seems to have a direct and clear association with peak MnO2 content of the rocks, which in turn presents a high possibility of Mo having adsorbed onto primary Mn-oxyhydroxides in the water column, thus providing evidence that Mn-oxide must have acted as an important Mo sink, at least locally. Finally, the carbonate-carbon isotope results provide a useful tool that brings the two stratigraphic sections “together“, in conjunction with other correlatable chemostratigraphic parameters (e.g. Co, Mg). The results demonstrate that bulk carbon fluxes and isotopic signals in the sediments must reflect primary processes of deposition, and that correlation across two apparently disparate lithostratigraphic sections can be effected. The key finding is that, at times, manganese deposition in one part of a vii stratified basin was evidently accompanied by simultaneous BIF deposition at another, thus painting a very complex picture of massive primary chemical precipitation of Fe and Mn at the dawn of the GOE. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
Chinese character learning with the aid of an ICT website among Mandarin Second Additional Language learners in South Africa: a case study
- Authors: Fu, Shuying
- Date: 2022-04-08
- Subjects: Mandarin dialects Study and teaching (Secondary) South Africa , Mandarin dialects Computer-assisted instruction for English speakers , Second language acquisition , Chinese characters , Information technology South Africa , Educational technology South Africa , Arch Chinese
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263590 , vital:53641
- Description: The teaching of Mandarin as a Second Additional Language (SAL) in South African schools was only introduced in 2016. The year 2018 saw the first Mandarin as SAL National Senior Certificate examination. Little research has been done on the teaching and learning of Mandarin as a SAL subject at the high school level in South Africa. Character learning and teaching are some of the most challenging aspects of this language teaching and learning. This research sought to investigate how beginner Mandarin SAL learners can be supported by a particular Information Communication Technology (ICT) website, www.archchinese.com (Arch Chinese), in their character learning. Learners’ ability to memorise Chinese characters is of utmost importance for their success in this language learning, especially for matriculants. To support the main research goal, this study set out to investigate the requirements for Chinese character learning, the role the website Arch Chinese plays in learners’ character learning and Mandarin SAL learners’ experience of using Arch Chinese as a learning tool. This research was conducted in the form of a case study within the interpretative paradigm. It adopted a questionnaire and document analysis for data collection to gain insight into the research topic. To get answers to the research questions posed above, the study analysed the Curriculum Assessment Policy Statement (CAPS) Mandarin SAL documents from Grade 4–12, the Independent Examination Board (IEB) Mandarin Subject Assessment Guidelines (SAGs), and a textbook for beginners, Learn Chinese with me: Student’s book 1 in relation to character learning. The features and functions of the website, Arch Chinese, were also evaluated and Mandarin SAL learners’ answers to a questionnaire on their use of the website Arch Chinese were analysed. The study found that character teaching and learning has not been given enough attention in the curriculum. It was only covered in the Intermediate Phase but was seldom mentioned in the Senior and Further Education and Training Phases in the curriculum. The CAPS Mandarin SAL documents do not consider the special characteristics of the Mandarin language, as this curriculum was based on the CAPS English Generic SAL document. As a result, the assessment requirements on writing (character count requirement in particular) were not realistic. The teaching approaches promoted in the curriculum and the teaching time do not correspond well with the teaching and learning of this language. Moreover, this study found that there was no vocabulary list prescribed in the curriculum and therefore a gap exists between the curriculum on paper and the curriculum in practice. The analysis of the IEB SAGs found that the assessments were suitable for the level of Mandarin SAL learners. This is because the IEB considered the characteristics of the Mandarin language, which is non-cognate, to the alphabet-based languages that respondents in this research spoke or were familiar with. At the same time, the analysis of the website and the learners’ questionnaire found that learners held a positive attitude towards their use of the website and that it proved to help facilitate Mandarin SAL learners in their character learning. This study ends with recommendations for teachers, policy makers, the IEB, and character-learning websites. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text: false
- Date Issued: 2022-04-08
- Authors: Fu, Shuying
- Date: 2022-04-08
- Subjects: Mandarin dialects Study and teaching (Secondary) South Africa , Mandarin dialects Computer-assisted instruction for English speakers , Second language acquisition , Chinese characters , Information technology South Africa , Educational technology South Africa , Arch Chinese
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263590 , vital:53641
- Description: The teaching of Mandarin as a Second Additional Language (SAL) in South African schools was only introduced in 2016. The year 2018 saw the first Mandarin as SAL National Senior Certificate examination. Little research has been done on the teaching and learning of Mandarin as a SAL subject at the high school level in South Africa. Character learning and teaching are some of the most challenging aspects of this language teaching and learning. This research sought to investigate how beginner Mandarin SAL learners can be supported by a particular Information Communication Technology (ICT) website, www.archchinese.com (Arch Chinese), in their character learning. Learners’ ability to memorise Chinese characters is of utmost importance for their success in this language learning, especially for matriculants. To support the main research goal, this study set out to investigate the requirements for Chinese character learning, the role the website Arch Chinese plays in learners’ character learning and Mandarin SAL learners’ experience of using Arch Chinese as a learning tool. This research was conducted in the form of a case study within the interpretative paradigm. It adopted a questionnaire and document analysis for data collection to gain insight into the research topic. To get answers to the research questions posed above, the study analysed the Curriculum Assessment Policy Statement (CAPS) Mandarin SAL documents from Grade 4–12, the Independent Examination Board (IEB) Mandarin Subject Assessment Guidelines (SAGs), and a textbook for beginners, Learn Chinese with me: Student’s book 1 in relation to character learning. The features and functions of the website, Arch Chinese, were also evaluated and Mandarin SAL learners’ answers to a questionnaire on their use of the website Arch Chinese were analysed. The study found that character teaching and learning has not been given enough attention in the curriculum. It was only covered in the Intermediate Phase but was seldom mentioned in the Senior and Further Education and Training Phases in the curriculum. The CAPS Mandarin SAL documents do not consider the special characteristics of the Mandarin language, as this curriculum was based on the CAPS English Generic SAL document. As a result, the assessment requirements on writing (character count requirement in particular) were not realistic. The teaching approaches promoted in the curriculum and the teaching time do not correspond well with the teaching and learning of this language. Moreover, this study found that there was no vocabulary list prescribed in the curriculum and therefore a gap exists between the curriculum on paper and the curriculum in practice. The analysis of the IEB SAGs found that the assessments were suitable for the level of Mandarin SAL learners. This is because the IEB considered the characteristics of the Mandarin language, which is non-cognate, to the alphabet-based languages that respondents in this research spoke or were familiar with. At the same time, the analysis of the website and the learners’ questionnaire found that learners held a positive attitude towards their use of the website and that it proved to help facilitate Mandarin SAL learners in their character learning. This study ends with recommendations for teachers, policy makers, the IEB, and character-learning websites. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text: false
- Date Issued: 2022-04-08
Chipangano: vigilantism and community responses in Mbare District, Zimbabwe, c.2000-2013
- Authors: Munyarari, Tinashe
- Date: 2018
- Subjects: Vigilantism Zimbabwe Mbare , ZANU-PF (Organization : Zimbabwe) , Zimbabwe History 1980- , Vigilantism Zimbabwe Mbare Public opinion , Collective memory Zimbabwe Mbare
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/62126 , vital:28130
- Description: This study examines an aspect of Zimbabwe’s political history, namely the emergence and operations of Chipangano vigilante group in Mbare (2000-2013) and how the community responded to the scourges of this vigilante group. This study shows that Chipangano, which means a pact, was formed with the intention to extend ZANU-PF patronage system, canvassing support and regain control of Mbare district from the MDC. The group consolidated itself as a shadow militia group for ZANU-PF that intimidated the opposition parties and coerced the general populace to attend ZANU-PF functions. It also shows that the vigilante group seized Harare City Council’s duties, such as collecting gate-takings from local and long distance public transport at Mbare Bus Terminal; controlling allocations of market stalls and collecting rents from market stalls, for personal benefits. The group also politicised the access to local state property. Chipangano’s collusion with ZANU-PF and state structures licensed it to engage in criminal activities with impunity, thus this thesis seeks to understand the relationship between the vigilantes, ZANU-PF and state structures. The activities of Chipangano such as abduction, intimidation, beatings, killings and displacement of people resulted in social trauma. This thesis will also explore how this phase of violence is remembered today by the research informants. , Thesis (MA) -- Faculty of Humanities, History, 2018
- Full Text:
- Date Issued: 2018
- Authors: Munyarari, Tinashe
- Date: 2018
- Subjects: Vigilantism Zimbabwe Mbare , ZANU-PF (Organization : Zimbabwe) , Zimbabwe History 1980- , Vigilantism Zimbabwe Mbare Public opinion , Collective memory Zimbabwe Mbare
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/62126 , vital:28130
- Description: This study examines an aspect of Zimbabwe’s political history, namely the emergence and operations of Chipangano vigilante group in Mbare (2000-2013) and how the community responded to the scourges of this vigilante group. This study shows that Chipangano, which means a pact, was formed with the intention to extend ZANU-PF patronage system, canvassing support and regain control of Mbare district from the MDC. The group consolidated itself as a shadow militia group for ZANU-PF that intimidated the opposition parties and coerced the general populace to attend ZANU-PF functions. It also shows that the vigilante group seized Harare City Council’s duties, such as collecting gate-takings from local and long distance public transport at Mbare Bus Terminal; controlling allocations of market stalls and collecting rents from market stalls, for personal benefits. The group also politicised the access to local state property. Chipangano’s collusion with ZANU-PF and state structures licensed it to engage in criminal activities with impunity, thus this thesis seeks to understand the relationship between the vigilantes, ZANU-PF and state structures. The activities of Chipangano such as abduction, intimidation, beatings, killings and displacement of people resulted in social trauma. This thesis will also explore how this phase of violence is remembered today by the research informants. , Thesis (MA) -- Faculty of Humanities, History, 2018
- Full Text:
- Date Issued: 2018
Climate change and small-scale farmer livelihood adaptation in rural border communities in Southern Africa: A case study of Ezondweni Village in Mchinji, Malawi
- Authors: Simango, Kennedy Khuzwayo
- Date: 2021-10-29
- Subjects: Farms, Small Malawi Mchinji , Climatic changes Economic aspects Malawi Mchinji , Climatic changes Risk management Malawi Mchinji , Crops and climate Malawi Mchinji , Sustainable agriculture Malawi Mchinji , Farmers Social networks Malawi Mchinji , Farm income Malawi Mchinji
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190008 , vital:44955
- Description: Southern Africa is a region increasingly experiencing the detrimental effects of climate change and variability. The rural areas in particular face unprecedented climate change-induced challenges in relation to small-scale farmers being able to pursue household-based livelihoods, and these farmers seek ways of adapting to climate change and variability in doing so. Some rural communities exist along territorial borders and their attempts at adapting to climate change entails cross-border networks and activities. In this context, this thesis examines small-scale farmer adaptation to climate change and variability in the small village of Ezondweni in Malawi near the Zambian border. Analytically, the study draws upon the Sustainable Livelihoods Framework as well as social network theory and the theory of reflexive agency put forward by Margaret Archer. A qualitative research design entailed informal interviews with a small number of Ezondweni villagers, focusing on their perceptions of climate change and their practices of climate change adaptation. The study demonstrates the diverse activities pursued by villagers, both within Malawi and beyond, in seeking to maintain household-based livelihoods, as well as the significance of mutually-supportive social networks which facilitate these livelihood processes. , Thesis (MSocSci) -- Faculty of Humanities, Social Science, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Simango, Kennedy Khuzwayo
- Date: 2021-10-29
- Subjects: Farms, Small Malawi Mchinji , Climatic changes Economic aspects Malawi Mchinji , Climatic changes Risk management Malawi Mchinji , Crops and climate Malawi Mchinji , Sustainable agriculture Malawi Mchinji , Farmers Social networks Malawi Mchinji , Farm income Malawi Mchinji
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190008 , vital:44955
- Description: Southern Africa is a region increasingly experiencing the detrimental effects of climate change and variability. The rural areas in particular face unprecedented climate change-induced challenges in relation to small-scale farmers being able to pursue household-based livelihoods, and these farmers seek ways of adapting to climate change and variability in doing so. Some rural communities exist along territorial borders and their attempts at adapting to climate change entails cross-border networks and activities. In this context, this thesis examines small-scale farmer adaptation to climate change and variability in the small village of Ezondweni in Malawi near the Zambian border. Analytically, the study draws upon the Sustainable Livelihoods Framework as well as social network theory and the theory of reflexive agency put forward by Margaret Archer. A qualitative research design entailed informal interviews with a small number of Ezondweni villagers, focusing on their perceptions of climate change and their practices of climate change adaptation. The study demonstrates the diverse activities pursued by villagers, both within Malawi and beyond, in seeking to maintain household-based livelihoods, as well as the significance of mutually-supportive social networks which facilitate these livelihood processes. , Thesis (MSocSci) -- Faculty of Humanities, Social Science, 2021
- Full Text:
- Date Issued: 2021-10-29
Cloning, expression, partial characterisation and application of a recombinant GH10 xylanase, XT6, from Geobacillus stearothermophilus T6 as an additive to chicken feeds
- Authors: Sithole, Tariro
- Date: 2022-04-06
- Subjects: Chicken feed industry , Chickens Feeding and feeds , Bacillus (Bacteria) , Xylanases , Polysaccharides , Geobacillus stearothermophilus
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/292693 , vital:57007
- Description: Monogastric animal farming has largely been sustained by feeding animals with grain feedstocks containing non-starch polysaccharides (NSPs) and anti-nutritive factors, which cause adverse effects, such as increased digesta viscosity and entrapment of nutrients, which leads to the inaccessibility of nutrients. These effects have been linked to a reduction in nutrient digestion and absorption, which results in a decreased feed conversion ratio, energy metabolism and animal growth. Monogastric animals do not produce enzymes that can hydrolyse these NSPs. The application of exogenous enzymes as supplements to animal feeds has been implemented to reduce viscosity and increase nutrient absorption in poultry and pigs over the past few decades. The aim of this study was to clone, express, partially characterise and apply a glycoside hydrolase (GH) family 10 xylanase (XT6), derived from Geobacillus stearothermophilus T6, as an additive to locally produced chicken feeds. The xt6 gene (1,236 bp) was subcloned and expressed in Escherichia coli DH5α and BL21(DE3) cells, respectively. Upon expression, XT6 had a molecular weight of 42 kDa and was partially purified by Ni-NTA chromatography and ultrafiltration. The purification step resulted in a yield of 66.7% with a 16.8-fold increase in purification. XT6 exhibited maximal activity when incubated at a pH and temperature of pH 6.0 and 70°C, respectively, with a high thermostability over a broad range of pH (2–9) and temperature (30–90 °C). The specific activities of XT6 on extracted soluble and insoluble wheat flour arabinoxylans were 110.9 U/mg and 63.98 U/mg, respectively. Kinetic data showed that XT6 displayed a higher catalytic activity and affinity (Vmax = 231.60 μmol/min/mg and KM = 2.759 mg/ml) for soluble wheat arabinoxylan, compared to insoluble wheat arabinoxylan (Vmax = 99.02 μmol/min/mg and KM = 5.058 mg/ml). High-performance liquid chromatography (HPLC) analysis showed that the enzyme hydrolysed wheat flour, arabinoxylan and chicken feeds, producing a range of xylooligosaccharides (XOS), with xylotetraose and xylopentaose being the predominant XOS species. Hydrolysis of both soluble and insoluble wheat flour arabinoxylans by XT6 led to a significant reduction in substrate viscosity. The effects of simulated gastrointestinal fluid contents, such as proteases, bile salts and mucins, on XT6 stability were also studied. Exposure of XT6 to pepsin did not significantly reduce its activity; however, the inhibitory effect of trypsin and mucin on XT6 was much greater. The presence of gut-derived bile salts had no iii | P a g e significant effect on XT6 activity. Finally, it was shown that the XOS produced from the hydrolysis of chicken feeds (starter and grower feeds) by XT6 significantly enhanced the growth of the probiotic bacteria B. subtilis, while there was no significant improvement in the growth of S. thermophilus and L. bulgaricus. In conclusion, the recombinantly produced XT6 demonstrated efficient hydrolysis of starter and grower feeds, and produced XOS that showed prebiotic activity on selected probiotic bacteria. In addition, the pH, temperature and simulated gastric juice content stability of XT6 renders it an attractive candidate as an additive for chicken feeds. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Sithole, Tariro
- Date: 2022-04-06
- Subjects: Chicken feed industry , Chickens Feeding and feeds , Bacillus (Bacteria) , Xylanases , Polysaccharides , Geobacillus stearothermophilus
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/292693 , vital:57007
- Description: Monogastric animal farming has largely been sustained by feeding animals with grain feedstocks containing non-starch polysaccharides (NSPs) and anti-nutritive factors, which cause adverse effects, such as increased digesta viscosity and entrapment of nutrients, which leads to the inaccessibility of nutrients. These effects have been linked to a reduction in nutrient digestion and absorption, which results in a decreased feed conversion ratio, energy metabolism and animal growth. Monogastric animals do not produce enzymes that can hydrolyse these NSPs. The application of exogenous enzymes as supplements to animal feeds has been implemented to reduce viscosity and increase nutrient absorption in poultry and pigs over the past few decades. The aim of this study was to clone, express, partially characterise and apply a glycoside hydrolase (GH) family 10 xylanase (XT6), derived from Geobacillus stearothermophilus T6, as an additive to locally produced chicken feeds. The xt6 gene (1,236 bp) was subcloned and expressed in Escherichia coli DH5α and BL21(DE3) cells, respectively. Upon expression, XT6 had a molecular weight of 42 kDa and was partially purified by Ni-NTA chromatography and ultrafiltration. The purification step resulted in a yield of 66.7% with a 16.8-fold increase in purification. XT6 exhibited maximal activity when incubated at a pH and temperature of pH 6.0 and 70°C, respectively, with a high thermostability over a broad range of pH (2–9) and temperature (30–90 °C). The specific activities of XT6 on extracted soluble and insoluble wheat flour arabinoxylans were 110.9 U/mg and 63.98 U/mg, respectively. Kinetic data showed that XT6 displayed a higher catalytic activity and affinity (Vmax = 231.60 μmol/min/mg and KM = 2.759 mg/ml) for soluble wheat arabinoxylan, compared to insoluble wheat arabinoxylan (Vmax = 99.02 μmol/min/mg and KM = 5.058 mg/ml). High-performance liquid chromatography (HPLC) analysis showed that the enzyme hydrolysed wheat flour, arabinoxylan and chicken feeds, producing a range of xylooligosaccharides (XOS), with xylotetraose and xylopentaose being the predominant XOS species. Hydrolysis of both soluble and insoluble wheat flour arabinoxylans by XT6 led to a significant reduction in substrate viscosity. The effects of simulated gastrointestinal fluid contents, such as proteases, bile salts and mucins, on XT6 stability were also studied. Exposure of XT6 to pepsin did not significantly reduce its activity; however, the inhibitory effect of trypsin and mucin on XT6 was much greater. The presence of gut-derived bile salts had no iii | P a g e significant effect on XT6 activity. Finally, it was shown that the XOS produced from the hydrolysis of chicken feeds (starter and grower feeds) by XT6 significantly enhanced the growth of the probiotic bacteria B. subtilis, while there was no significant improvement in the growth of S. thermophilus and L. bulgaricus. In conclusion, the recombinantly produced XT6 demonstrated efficient hydrolysis of starter and grower feeds, and produced XOS that showed prebiotic activity on selected probiotic bacteria. In addition, the pH, temperature and simulated gastric juice content stability of XT6 renders it an attractive candidate as an additive for chicken feeds. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2022
- Full Text:
- Date Issued: 2022-04-06
Coaches perspective on the positional demands of school boy (u18/u19) rugby players during a 70-minute match
- Authors: Barnard, Devon Vernon
- Date: 2021-10
- Subjects: Rugby football coaches South Africa , Rugby Union football players South Africa , Rugby football injuries South Africa , School sports South Africa , School sports Coaching South Africa , School sports Physiological aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190089 , vital:44962
- Description: INTRODUCTION: Rugby union has been one of the team sports that has grown over the last few years, and the margin between success and failure for teams has become narrower as the years have gone by. The game consists of players going through different movements such as sprints and/or collisions, that vary in intensity. The demands that face schoolboy rugby players are not well understood, and the lack of research in this area leads to a potential lack of understanding of the perceptions that coaches have about the demands that schoolboys are faced with during a match. OBJECTIVE: Therefore, the purpose of this study was to determine the perceptions that the schoolboy rugby coaches had surrounding the demands that their players are faced with during a 70-minute match. There were a few secondary purposes of the study, such as determining which school, government or private, had a better understanding or perception of the demands, as well as comparing strength and conditioning coaches’ perceptions to regular coaches’ perceptions. METHODS: This was a cross-sectional, descriptive study to determine the coach’s perceptions. These perceptions were collected through an online questionnaire, which consisted of ten sections and 74 questions. The questionnaire was piloted on a subject group with different types of experience. Coaches from the top 100 schools list were contacted through their school website. RESULTS: The questionnaire had a 72% response rate: 41 responses from 51 emails. The 41 responses consisted of 23 government schools and 18 private schools, which included 11 of the top 20 rugby schools in South Africa, with most responses coming from the Eastern Cape (41.5%). Results indicated that a government school’s coaches had significantly (p<0.05) more experience than private schools’ coaches, and that they had significantly (p<0.05) better academic qualifications than private schools. However, strength and conditioning coaches had significantly (p<0.01) better academic qualifications than coach, whereas coaches had significantly (p<0.01) better coaching qualifications than strength and conditioning coaches. CONCLUSION: “Experience has been shown to be a potential reason for what is described as a good coach”. This is also another potential reason why government schools are a dominant force in schoolboy rugby in South Africa. However, this is also coupled with better qualifications showing the dual importance of both experience and education. This study has shown that coaches, within a South African cohort, overall had good general perception of the demands of school level rugby matches. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2021
- Full Text:
- Date Issued: 2021-10
- Authors: Barnard, Devon Vernon
- Date: 2021-10
- Subjects: Rugby football coaches South Africa , Rugby Union football players South Africa , Rugby football injuries South Africa , School sports South Africa , School sports Coaching South Africa , School sports Physiological aspects
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190089 , vital:44962
- Description: INTRODUCTION: Rugby union has been one of the team sports that has grown over the last few years, and the margin between success and failure for teams has become narrower as the years have gone by. The game consists of players going through different movements such as sprints and/or collisions, that vary in intensity. The demands that face schoolboy rugby players are not well understood, and the lack of research in this area leads to a potential lack of understanding of the perceptions that coaches have about the demands that schoolboys are faced with during a match. OBJECTIVE: Therefore, the purpose of this study was to determine the perceptions that the schoolboy rugby coaches had surrounding the demands that their players are faced with during a 70-minute match. There were a few secondary purposes of the study, such as determining which school, government or private, had a better understanding or perception of the demands, as well as comparing strength and conditioning coaches’ perceptions to regular coaches’ perceptions. METHODS: This was a cross-sectional, descriptive study to determine the coach’s perceptions. These perceptions were collected through an online questionnaire, which consisted of ten sections and 74 questions. The questionnaire was piloted on a subject group with different types of experience. Coaches from the top 100 schools list were contacted through their school website. RESULTS: The questionnaire had a 72% response rate: 41 responses from 51 emails. The 41 responses consisted of 23 government schools and 18 private schools, which included 11 of the top 20 rugby schools in South Africa, with most responses coming from the Eastern Cape (41.5%). Results indicated that a government school’s coaches had significantly (p<0.05) more experience than private schools’ coaches, and that they had significantly (p<0.05) better academic qualifications than private schools. However, strength and conditioning coaches had significantly (p<0.01) better academic qualifications than coach, whereas coaches had significantly (p<0.01) better coaching qualifications than strength and conditioning coaches. CONCLUSION: “Experience has been shown to be a potential reason for what is described as a good coach”. This is also another potential reason why government schools are a dominant force in schoolboy rugby in South Africa. However, this is also coupled with better qualifications showing the dual importance of both experience and education. This study has shown that coaches, within a South African cohort, overall had good general perception of the demands of school level rugby matches. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2021
- Full Text:
- Date Issued: 2021-10
Coastal movements and estuarine use of sub-adult and adult leervis, lichia amia: results from long-term acoustic tracking
- Authors: Mxo, Rebecca Vuyolwethu
- Date: 2023-03-29
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/422314 , vital:71930
- Description: Information on fish movement is important not only for understanding a species’ ecological importance, but also for developing appropriate conservation and management policies that are critical for food security and biodiversity preservation. This information is particularly important for species that occupy different habitats at different life history stages, and display predictable movement patterns, such as an annual spawning migration. Leervis Lichia amia is an estuary-dependent fishery species of high ecological and recreational importance in South Africa. There has been a steady decline in catch-per-unit-effort in the marine recreational fishery for this species over the past 20 years, and the most recent stock assessment classified the adult stock as collapsed. This study investigates L. amia multi-year coastal migrations and estuarine habitat use of sub-adult and adult fish tagged with long-life acoustic transmitters Seventy-eight L. amia (two juveniles, fifty-four subadults, and twenty-one adults) were tagged throughout their South African distribution and monitored between 2011 and 2020 producing a decade long dataset. Results show that regardless of the tagging region, clear migration patterns were observed, demonstrating that both sub-adult and adult L. amia migrate annually to KZN in the austral winter and predictably return to the WC and EC waters in the summer. The likelihood of partial migration was also identified, with the coexistence of migratory and resident behaviors within a single L. amia population. In addition, Overwintering behaviour was also observed with L. amia adults that remained resident throughout the year, foregoing the annual migration, phenomenon known as skipped spawning, and homing behaviour, where L. amia, particularly those tagged in the EC and WC, were recorded returning to previously occupied tagging locations and surrounding areas. The importance of estuaries to sub-adult and adult fish was also assessed and identified the importance of estuaries not only to subadults but also to adults. Estuary visits were strongly influenced by the environment which the fish was tagged in, temporal and seasonal changes, and life-history stages. The predictability of their migrations (almost to the day), the varied migratory behaviour (overwintering), returning to sites of familiarity post-migration, and long-term dependency on estuaries even as sub-adults and adults, provide motivation for increased protection of this species, including extending the network of estuarine protected areas in the country, and a closed fishing season, particularly during the annual winter migration. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-03-29
- Authors: Mxo, Rebecca Vuyolwethu
- Date: 2023-03-29
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/422314 , vital:71930
- Description: Information on fish movement is important not only for understanding a species’ ecological importance, but also for developing appropriate conservation and management policies that are critical for food security and biodiversity preservation. This information is particularly important for species that occupy different habitats at different life history stages, and display predictable movement patterns, such as an annual spawning migration. Leervis Lichia amia is an estuary-dependent fishery species of high ecological and recreational importance in South Africa. There has been a steady decline in catch-per-unit-effort in the marine recreational fishery for this species over the past 20 years, and the most recent stock assessment classified the adult stock as collapsed. This study investigates L. amia multi-year coastal migrations and estuarine habitat use of sub-adult and adult fish tagged with long-life acoustic transmitters Seventy-eight L. amia (two juveniles, fifty-four subadults, and twenty-one adults) were tagged throughout their South African distribution and monitored between 2011 and 2020 producing a decade long dataset. Results show that regardless of the tagging region, clear migration patterns were observed, demonstrating that both sub-adult and adult L. amia migrate annually to KZN in the austral winter and predictably return to the WC and EC waters in the summer. The likelihood of partial migration was also identified, with the coexistence of migratory and resident behaviors within a single L. amia population. In addition, Overwintering behaviour was also observed with L. amia adults that remained resident throughout the year, foregoing the annual migration, phenomenon known as skipped spawning, and homing behaviour, where L. amia, particularly those tagged in the EC and WC, were recorded returning to previously occupied tagging locations and surrounding areas. The importance of estuaries to sub-adult and adult fish was also assessed and identified the importance of estuaries not only to subadults but also to adults. Estuary visits were strongly influenced by the environment which the fish was tagged in, temporal and seasonal changes, and life-history stages. The predictability of their migrations (almost to the day), the varied migratory behaviour (overwintering), returning to sites of familiarity post-migration, and long-term dependency on estuaries even as sub-adults and adults, provide motivation for increased protection of this species, including extending the network of estuarine protected areas in the country, and a closed fishing season, particularly during the annual winter migration. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-03-29
Comparison of a novel HPLC method and conventional protein assays for the quantitation of insulin aspart in Novorapid®
- Authors: Dickson, Courtney Rae
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/290704 , vital:56776
- Description: Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Dickson, Courtney Rae
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/290704 , vital:56776
- Description: Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2022
- Full Text:
- Date Issued: 2022-04-06
Comparison of the metabolic physiology of exploited and unexploited populations of red roman (Chrysoblephus laticeps) along the south coast of South Africa
- Authors: Nabani, Xolani Prince
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424358 , vital:72146
- Description: Anthropogenic-induced climate change and exploitation pose threat to many marine fishes on which a vast majority of people around the world depend. Rapid changes in sea surface temperature have a direct impact on the physiology of ectothermic organisms such as fish, potentially resulting in changes to population distribution, abundance, and demographics. In the face of climate change, the impacts of increasing temperature variability on fish populations may be exacerbated by exploitation. Understanding how the resilience of exploited populations is affected by climate change is critical to predict how fishes will respond in the future. This study aimed to augment our knowledge on the impact of exploitation and thermal variability on fishes by comparing the thermal physiology of an exploited and unexploited population of the resident, reef-dwelling, Chrysoblephus laticeps. Twenty live fish were collected from the exploited, Cape St Francis and 18 fish from the unexploited, Goukamma Marine Protected Area and transported to the laboratory. The metabolic performance, in terms of standard metabolic rate (SMR), maximum metabolic rate (MMR) and aerobic scope (AS) of individual C. laticeps were estimated repeatedly at 10 ℃, 16 °C and 21 °C. Linear mixed effects models were used to examine the relationship between temperature, population, and metabolic rate and a ‘cvequality’ test analysis was used to compare the variance structure of the metabolic rate regression model for each population. Overall, the findings of this study show that Chrysoblephus laticeps from the unexploited population maintains a significantly higher aerobic scope (AS) across all temperature treatments (10, 16 and 21 ℃) when compared with those from the exploited population. In addition, the maximum metabolic rate (MMR) of individuals from the unexploited population was significantly higher than that of individuals from the exploited population, but there was no evidence to suggest that variability was significantly different between the populations. On the other hand, the individuals from an exploited population had a significantly higher standard metabolic rate (SMR) at high temperatures of 21 ℃, while the unexploited population had a low SMR at these high temperatures, but a high SMR at 10 ℃. Despite these differences there was no significant variation in the SMR between the two populations. The findings of this study confirm previous work on different exploited and unexploited populations of C. laticeps and together these findings suggest that hook and line exploitation lead to reduced physiological phenotypic diversity and reduced physiological performance in exploited fish populations. These findings emphasise the importance of incorporating the iii physiological information to develop viable fisheries management tools in the context of climate change. This study also highlights the effectiveness of MPAs in conserving highperformance physiological phenotypes to maintain phenotypic diversity in fish populations. Future research should aim to evaluate the efficacy of existing MPAs in preserving the physiological diversity of important hook and line fisheries species, while fisheries managers should consider augmenting their approaches through the incorporation of well-designed MPA’s to promote physiological diversity. This will be critical to advance the development of sustainable management practices, not only in a South African context but globally, where oceanic and coastal environmental conditions are expected to rapidly change in the future. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Nabani, Xolani Prince
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424358 , vital:72146
- Description: Anthropogenic-induced climate change and exploitation pose threat to many marine fishes on which a vast majority of people around the world depend. Rapid changes in sea surface temperature have a direct impact on the physiology of ectothermic organisms such as fish, potentially resulting in changes to population distribution, abundance, and demographics. In the face of climate change, the impacts of increasing temperature variability on fish populations may be exacerbated by exploitation. Understanding how the resilience of exploited populations is affected by climate change is critical to predict how fishes will respond in the future. This study aimed to augment our knowledge on the impact of exploitation and thermal variability on fishes by comparing the thermal physiology of an exploited and unexploited population of the resident, reef-dwelling, Chrysoblephus laticeps. Twenty live fish were collected from the exploited, Cape St Francis and 18 fish from the unexploited, Goukamma Marine Protected Area and transported to the laboratory. The metabolic performance, in terms of standard metabolic rate (SMR), maximum metabolic rate (MMR) and aerobic scope (AS) of individual C. laticeps were estimated repeatedly at 10 ℃, 16 °C and 21 °C. Linear mixed effects models were used to examine the relationship between temperature, population, and metabolic rate and a ‘cvequality’ test analysis was used to compare the variance structure of the metabolic rate regression model for each population. Overall, the findings of this study show that Chrysoblephus laticeps from the unexploited population maintains a significantly higher aerobic scope (AS) across all temperature treatments (10, 16 and 21 ℃) when compared with those from the exploited population. In addition, the maximum metabolic rate (MMR) of individuals from the unexploited population was significantly higher than that of individuals from the exploited population, but there was no evidence to suggest that variability was significantly different between the populations. On the other hand, the individuals from an exploited population had a significantly higher standard metabolic rate (SMR) at high temperatures of 21 ℃, while the unexploited population had a low SMR at these high temperatures, but a high SMR at 10 ℃. Despite these differences there was no significant variation in the SMR between the two populations. The findings of this study confirm previous work on different exploited and unexploited populations of C. laticeps and together these findings suggest that hook and line exploitation lead to reduced physiological phenotypic diversity and reduced physiological performance in exploited fish populations. These findings emphasise the importance of incorporating the iii physiological information to develop viable fisheries management tools in the context of climate change. This study also highlights the effectiveness of MPAs in conserving highperformance physiological phenotypes to maintain phenotypic diversity in fish populations. Future research should aim to evaluate the efficacy of existing MPAs in preserving the physiological diversity of important hook and line fisheries species, while fisheries managers should consider augmenting their approaches through the incorporation of well-designed MPA’s to promote physiological diversity. This will be critical to advance the development of sustainable management practices, not only in a South African context but globally, where oceanic and coastal environmental conditions are expected to rapidly change in the future. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2023
- Full Text:
- Date Issued: 2023-10-13
Composition and fate of triclosan in the sludge from wastewater treatment in Grahamstown, South Africa and Tiaret, Algeria
- Authors: Ncube, Mbonisi
- Date: 2017
- Subjects: Sewage sludge , Sewage Purification South Africa Grahamstown , Sewage Purification Algeria Tiaret , Sewage sludge as fertilizer , Anti-infective agents
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/65156 , vital:28697
- Description: Physicochemical properties such as pH, specific surface area (SSA), cationic exchange capacity (CEC), loss on ignition (LOI), pathogens, plant nutrients (nitrates, ammonium and phosphates), and heavy metals (manganese, copper, lead and cadmium) were determined for sewage sludge from Grahamstown and Tiaret. The values obtained were log transformed thereafter a t-test at 5 % level of significance was used to test for the difference in each parameter for both sludges. The pH of sludge was determined in 1:3 water, 16 water, 1:3 0.01 M calcium chloride and 1:3 1 M potassium chloride. The pH for Grahamstown and Tiaret sludge were in the ranges of 6.66-7.11 and 7.88-8.18 respectively. The SSA values for Grahamstown and Tiaret were 218 ± 108 and 261 ± 99.9 m2/g, and the CEC values were 119 ± 2.09 and 136 ± 6.03 mEq/100, respectively. The LOI values obtained were 1.33 ± 0.03 and 1.48 ± 0.11 % for Grahamstown and Tiaret, respectively. E. coll and heterotrophic bacteria were the pathogens determined, and were extracted from sludge using sterile saline and nutrient broth. The concentration of E. coll in Grahamstown and Tiaret sludge were 468 ± 7.63 and 7769 ± 1268 CFU/g d.w and for heterotrophic bacteria were 1.17x109 ± 7.42x108 and 1.43x109 ± 9.11 x108 CFU/g d.w. For Grahamstown sludge, the concentration of nitrates, ammonium and phosphates were 55.61 ± 55.20 mg/g d.w, 6.60 ± 2.36 mg/g d.w and 1.40 ± 0.30 mg/g d.w, respectively. For Tiaret sludge, the concentration of nitrates, ammonium and phosphates were 2.56 ± 2.90 mg/g d.w, 0.64 ± 0.45 mg/g d.w and 0.24 ± 0.19 mg/g d.w, respectively. The concentration of Mn, Cu, Pb and Cd in Grahamstown sludge were 423 ± 101, 353 ± 92, 40.2 ± 20 and 0.0 mg/kg d.w respectively, and for Tiaret sludge, the corresponding concentrations were 358± 295, 549±50, 1427± 1352 and 1.54 ± 0.61 mg/kg d.w. Sewage sludge was found to contain Triclosan, and solubility studies of the compound were conducted using sodium deoxycholate and sodium lithocholate. The apparent solubilities and rate constants indicated in brackets of TCS at 37 °C were 35.4 ± 1.21 mg/L (1.28 ± 0.36 Hr-) and 14.4 ± 0.34 mg/L (0.99 ± 0.17 Hr-) in sodium lithocholate and sodium deoxycholate, respectively. The apparent solubilities and rate constants indicated in brackets of TCS at 15 °C were 32.3 ± 0.88 mg/L (2.16 ± 0.80 Hr-) and 14.2 ± 0.39 mg/L (1.02 ± 0.17 Hr-) in sodium lithocholate and sodium deoxycholate, respectively. Triclosan was extracted from sludge using 1 g/L sodium deoxycholate and the determined concentration were 142 ± 33.5 gg/g d.w for Grahamstown sludge and 0-12 gg/g d.w for Tiaret sludge. Finally plant growth studies were conducted on radish and garden cress plants using Grahamstown sludge at 0, 20, 40, 80 and 100 % treatments. Statistical analysis (t-test and Kruskal-Wallis) at 5 % level of significance was done to compare growth parameters between control and different sludge treatments. For radish plants, the values for plant height, root length, number of leaves, leaf length and dry mass were 28.4-80-7 mm, 4.3-44.7 mm, 3.3-17.0 mm, 2.3-4.0 leaves and 6.3-15.3 %, respectively. For garden cress, the values for plant height, root length, number of leaves, leaf length and dry mass were 13.7-25.0 mm, 7.7-20.3 mm, 5.7-8.3 leaves, 3.0-8.3 mm and 8.8-15.0 %, respectively. Twenty percent (20 %) sludge treatment gave the best results in radish and garden cress plants with respect to plant height, root length, number of leaves and dry mass. Triclosan concentration in radish and garden cress plants was below the detection limit of 32.4 gg/g d.w. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2017
- Full Text:
- Date Issued: 2017
- Authors: Ncube, Mbonisi
- Date: 2017
- Subjects: Sewage sludge , Sewage Purification South Africa Grahamstown , Sewage Purification Algeria Tiaret , Sewage sludge as fertilizer , Anti-infective agents
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/65156 , vital:28697
- Description: Physicochemical properties such as pH, specific surface area (SSA), cationic exchange capacity (CEC), loss on ignition (LOI), pathogens, plant nutrients (nitrates, ammonium and phosphates), and heavy metals (manganese, copper, lead and cadmium) were determined for sewage sludge from Grahamstown and Tiaret. The values obtained were log transformed thereafter a t-test at 5 % level of significance was used to test for the difference in each parameter for both sludges. The pH of sludge was determined in 1:3 water, 16 water, 1:3 0.01 M calcium chloride and 1:3 1 M potassium chloride. The pH for Grahamstown and Tiaret sludge were in the ranges of 6.66-7.11 and 7.88-8.18 respectively. The SSA values for Grahamstown and Tiaret were 218 ± 108 and 261 ± 99.9 m2/g, and the CEC values were 119 ± 2.09 and 136 ± 6.03 mEq/100, respectively. The LOI values obtained were 1.33 ± 0.03 and 1.48 ± 0.11 % for Grahamstown and Tiaret, respectively. E. coll and heterotrophic bacteria were the pathogens determined, and were extracted from sludge using sterile saline and nutrient broth. The concentration of E. coll in Grahamstown and Tiaret sludge were 468 ± 7.63 and 7769 ± 1268 CFU/g d.w and for heterotrophic bacteria were 1.17x109 ± 7.42x108 and 1.43x109 ± 9.11 x108 CFU/g d.w. For Grahamstown sludge, the concentration of nitrates, ammonium and phosphates were 55.61 ± 55.20 mg/g d.w, 6.60 ± 2.36 mg/g d.w and 1.40 ± 0.30 mg/g d.w, respectively. For Tiaret sludge, the concentration of nitrates, ammonium and phosphates were 2.56 ± 2.90 mg/g d.w, 0.64 ± 0.45 mg/g d.w and 0.24 ± 0.19 mg/g d.w, respectively. The concentration of Mn, Cu, Pb and Cd in Grahamstown sludge were 423 ± 101, 353 ± 92, 40.2 ± 20 and 0.0 mg/kg d.w respectively, and for Tiaret sludge, the corresponding concentrations were 358± 295, 549±50, 1427± 1352 and 1.54 ± 0.61 mg/kg d.w. Sewage sludge was found to contain Triclosan, and solubility studies of the compound were conducted using sodium deoxycholate and sodium lithocholate. The apparent solubilities and rate constants indicated in brackets of TCS at 37 °C were 35.4 ± 1.21 mg/L (1.28 ± 0.36 Hr-) and 14.4 ± 0.34 mg/L (0.99 ± 0.17 Hr-) in sodium lithocholate and sodium deoxycholate, respectively. The apparent solubilities and rate constants indicated in brackets of TCS at 15 °C were 32.3 ± 0.88 mg/L (2.16 ± 0.80 Hr-) and 14.2 ± 0.39 mg/L (1.02 ± 0.17 Hr-) in sodium lithocholate and sodium deoxycholate, respectively. Triclosan was extracted from sludge using 1 g/L sodium deoxycholate and the determined concentration were 142 ± 33.5 gg/g d.w for Grahamstown sludge and 0-12 gg/g d.w for Tiaret sludge. Finally plant growth studies were conducted on radish and garden cress plants using Grahamstown sludge at 0, 20, 40, 80 and 100 % treatments. Statistical analysis (t-test and Kruskal-Wallis) at 5 % level of significance was done to compare growth parameters between control and different sludge treatments. For radish plants, the values for plant height, root length, number of leaves, leaf length and dry mass were 28.4-80-7 mm, 4.3-44.7 mm, 3.3-17.0 mm, 2.3-4.0 leaves and 6.3-15.3 %, respectively. For garden cress, the values for plant height, root length, number of leaves, leaf length and dry mass were 13.7-25.0 mm, 7.7-20.3 mm, 5.7-8.3 leaves, 3.0-8.3 mm and 8.8-15.0 %, respectively. Twenty percent (20 %) sludge treatment gave the best results in radish and garden cress plants with respect to plant height, root length, number of leaves and dry mass. Triclosan concentration in radish and garden cress plants was below the detection limit of 32.4 gg/g d.w. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2017
- Full Text:
- Date Issued: 2017
Composition and physiological roles of gut microbiota in the False Coding Moth (Thaumatotibia leucotreta)
- Authors: Richardson, Perryn Heather
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424457 , vital:72155
- Description: Gut microbiota can have a profound influence on host performance, behaviour and fitness. For False Codling Moth (FCM), Thaumatotibia leucotreta (Lepidoptera: Tortricidae), a major pest of citrus in South Africa, little work has been undertaken to date on gut microbe diversity or its influence on the host. This thesis aimed to i) characterise the gut microbiome of FCM under laboratory conditions and in FCM from the field, ii) and produce moths with reduced gut microbiota through egg dechorionation, which was followed by iii) the measurement of a suite of physiological traits, namely mass, survival and thermal stress in FCM from normal laboratory, dechorionated laboratory and field collected larvae that may be indicative of overall field performance. We aimed to directly test the hypothesis that gut microbial diversity partly determines insect performance and fitness by measuring its effects on growth, development, and tolerance to cold temperatures in FCM. FCM eggs that underwent dechorionation with sodium hypochlorite had an overall effect on larval survival, egg morphology and both larval and adult moth physiological measures. Increasing concentrations of sodium hypochlorite significantly decreased insect survival, (𝜒2(1, n = 10 850) = 21.724, p-value < 0.0001), with a concentration of ≈3.69% as the concentration limit (p-value < 0.001). Successful dechorionation of FCM was achieved with a wash of sodium hypochlorite at around 3.69% concentration and was visually confirmed by reduction of FCM egg surface area, (𝜒2(25, n = 260) p-value < 0.0001) and Scanning Electron Micrographs of the egg morphology. The gut microbiome of FCM from the different focus treatments was successfully characterized. Identification of the dominant bacterial families in these microbiomes revealed Xanthobacteraceae, Beijerinckiaceae and Burkholderiaceae in both the laboratory reared and field collected larvae, which suggests their systematic association with T. leucotreta. The most abundant genera were revealed as Bradyrhizobium, Methylobacterium and Burkholderia-Caballeronia-Paraburkholderia. Comparison of larval mass showed that treatment (dechorionated or not) had a significant effect on larval mass (𝜒2(2, n = 230) = 22.703, p-value < 0.001), field larvae were heavier than both control larvae and larvae with a disrupted gut microbiome. However, adult insects with a disrupted gut microbiome had more mass than individuals from the control and field-collected larvae with intact gut microbiomes (𝜒2(2, n = 230) = 39.074, p-value < 0.001). Despite the difference in mass between larval treatments, there was no significant difference in relative protein (𝜒2(2, n = 24) = 5.680, p-value = 0.06), carbohydrate (𝜒2(2, n = 24) = 3.940, p-value = 0.14) or lipid (𝜒2(2, n = 24) = 6.032, p-value = 0.05) content between individuals from the control and dechorionated treatments and field-collected individuals. Turning to thermal physiology, insects collected from the field took significantly longer to recover from chill coma than both laboratory treatments with intact and disrupted gut microbiomes (𝜒2(2, n = 129 = 39.659, p-value < 0.001). In addition, exposure to cold stress showed that treatment had a significant effect on insect mortality (𝜒2(2, n = 272) = 9.176, p-value = 0.01), with individuals from the control and dechorionated treatment being less likely to die after experiencing cold stress compared to field-collected individuals. Differences in the mass and thermal tolerance of insects with intact and disrupted gut microbiota suggest that gut microbiota may play an important role in the cold performance of T. leucotreta, and these findings constitute the basis for future molecular work on the functions of these bacterial taxa. This research highlights the need for consideration of the effects of T. leucotreta microbiome in current pest control programs. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Richardson, Perryn Heather
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424457 , vital:72155
- Description: Gut microbiota can have a profound influence on host performance, behaviour and fitness. For False Codling Moth (FCM), Thaumatotibia leucotreta (Lepidoptera: Tortricidae), a major pest of citrus in South Africa, little work has been undertaken to date on gut microbe diversity or its influence on the host. This thesis aimed to i) characterise the gut microbiome of FCM under laboratory conditions and in FCM from the field, ii) and produce moths with reduced gut microbiota through egg dechorionation, which was followed by iii) the measurement of a suite of physiological traits, namely mass, survival and thermal stress in FCM from normal laboratory, dechorionated laboratory and field collected larvae that may be indicative of overall field performance. We aimed to directly test the hypothesis that gut microbial diversity partly determines insect performance and fitness by measuring its effects on growth, development, and tolerance to cold temperatures in FCM. FCM eggs that underwent dechorionation with sodium hypochlorite had an overall effect on larval survival, egg morphology and both larval and adult moth physiological measures. Increasing concentrations of sodium hypochlorite significantly decreased insect survival, (𝜒2(1, n = 10 850) = 21.724, p-value < 0.0001), with a concentration of ≈3.69% as the concentration limit (p-value < 0.001). Successful dechorionation of FCM was achieved with a wash of sodium hypochlorite at around 3.69% concentration and was visually confirmed by reduction of FCM egg surface area, (𝜒2(25, n = 260) p-value < 0.0001) and Scanning Electron Micrographs of the egg morphology. The gut microbiome of FCM from the different focus treatments was successfully characterized. Identification of the dominant bacterial families in these microbiomes revealed Xanthobacteraceae, Beijerinckiaceae and Burkholderiaceae in both the laboratory reared and field collected larvae, which suggests their systematic association with T. leucotreta. The most abundant genera were revealed as Bradyrhizobium, Methylobacterium and Burkholderia-Caballeronia-Paraburkholderia. Comparison of larval mass showed that treatment (dechorionated or not) had a significant effect on larval mass (𝜒2(2, n = 230) = 22.703, p-value < 0.001), field larvae were heavier than both control larvae and larvae with a disrupted gut microbiome. However, adult insects with a disrupted gut microbiome had more mass than individuals from the control and field-collected larvae with intact gut microbiomes (𝜒2(2, n = 230) = 39.074, p-value < 0.001). Despite the difference in mass between larval treatments, there was no significant difference in relative protein (𝜒2(2, n = 24) = 5.680, p-value = 0.06), carbohydrate (𝜒2(2, n = 24) = 3.940, p-value = 0.14) or lipid (𝜒2(2, n = 24) = 6.032, p-value = 0.05) content between individuals from the control and dechorionated treatments and field-collected individuals. Turning to thermal physiology, insects collected from the field took significantly longer to recover from chill coma than both laboratory treatments with intact and disrupted gut microbiomes (𝜒2(2, n = 129 = 39.659, p-value < 0.001). In addition, exposure to cold stress showed that treatment had a significant effect on insect mortality (𝜒2(2, n = 272) = 9.176, p-value = 0.01), with individuals from the control and dechorionated treatment being less likely to die after experiencing cold stress compared to field-collected individuals. Differences in the mass and thermal tolerance of insects with intact and disrupted gut microbiota suggest that gut microbiota may play an important role in the cold performance of T. leucotreta, and these findings constitute the basis for future molecular work on the functions of these bacterial taxa. This research highlights the need for consideration of the effects of T. leucotreta microbiome in current pest control programs. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2023
- Full Text:
- Date Issued: 2023-10-13
Composition portfolio
- Authors: Moss, Keith
- Date: 2007
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193724 , vital:45390
- Description: Whitacre's music is primarily diatonic with subtle modulations, where the new key is always preserved diatonicaliy as well. I refer to this style as expanded diatonicism. Examples in my work of expanded diatonicism within this portfolio are to be found in navem ad somnium, Wynken, Blynken and Nod, as well as Hymn for Brass. My applications of expanded diatonic practices within each of these works are discussed in a separate appendix within the body of this portfolio. That these works are vocal or have a vocal inspiration (Hymn for Brass) reveals the extent of my initial reaction to Whitacre's music during a choral rehearsal. Furthermore, in my vocal compositions especially I chose texts which frequently gravitate towards ideas related to water, the ocean and ships. Whilst water has a soothing and inspiring influence upon me, presumably evidenced in my expanded diatonicism, it also represents my journey and investigation into the sound work of Whitacre in particular. It may be noticed that many of my works in this portfolio have religious orientated themes. I am a Christian, and belong to a Berean 2 Congregational Church. Whilst I am not Catholic or Anglican, I nonetheless have made use of texts from the liturgy of these denominations, as they emphasise the basis of my Christian faith. Why I chose Hymn for Brass as a title could possibly be construed as a religious reference, however it was named after the piece was written, and had no theological connotations in its inception save for the hymnody style of the orchestration. Providence and The Eventide both have a Christian philosophical foundation which is explored in depth in the accompanying appendix. The latter work explores an extension of my expanded diatonic style through incorporating aspects of chromaticism. The rationale for this is dealt with in my discussion of this work. This portfolio represents an overview of my compositional activities to date and displays my growing confidence with the technical aspects of composition as well as my yearning for experimentation with new ideas and manners of expression. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2007
- Full Text:
- Date Issued: 2007
- Authors: Moss, Keith
- Date: 2007
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193724 , vital:45390
- Description: Whitacre's music is primarily diatonic with subtle modulations, where the new key is always preserved diatonicaliy as well. I refer to this style as expanded diatonicism. Examples in my work of expanded diatonicism within this portfolio are to be found in navem ad somnium, Wynken, Blynken and Nod, as well as Hymn for Brass. My applications of expanded diatonic practices within each of these works are discussed in a separate appendix within the body of this portfolio. That these works are vocal or have a vocal inspiration (Hymn for Brass) reveals the extent of my initial reaction to Whitacre's music during a choral rehearsal. Furthermore, in my vocal compositions especially I chose texts which frequently gravitate towards ideas related to water, the ocean and ships. Whilst water has a soothing and inspiring influence upon me, presumably evidenced in my expanded diatonicism, it also represents my journey and investigation into the sound work of Whitacre in particular. It may be noticed that many of my works in this portfolio have religious orientated themes. I am a Christian, and belong to a Berean 2 Congregational Church. Whilst I am not Catholic or Anglican, I nonetheless have made use of texts from the liturgy of these denominations, as they emphasise the basis of my Christian faith. Why I chose Hymn for Brass as a title could possibly be construed as a religious reference, however it was named after the piece was written, and had no theological connotations in its inception save for the hymnody style of the orchestration. Providence and The Eventide both have a Christian philosophical foundation which is explored in depth in the accompanying appendix. The latter work explores an extension of my expanded diatonic style through incorporating aspects of chromaticism. The rationale for this is dealt with in my discussion of this work. This portfolio represents an overview of my compositional activities to date and displays my growing confidence with the technical aspects of composition as well as my yearning for experimentation with new ideas and manners of expression. , Thesis (MMus) -- Faculty of Humanities, Music and Musicology, 2007
- Full Text:
- Date Issued: 2007
Composition Portfolio
- Authors: Bessey, Warren Gregory
- Date: 2023-04-10
- Subjects: Composition (Music) , Zulu (African people) Songs and music , Music Cross-cultural studies , uMkabayi kaJama , Nandi , Nobility South Africa Zululand History
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/404940 , vital:70123
- Description: Excerpt from Introduction: My interest in the Zulu royal family intensified as I began to read many stories and have lengthy conversations with members of the Zulu royal family and others, including Dr Maxwell Shamase (University of Zululand), about Zulu history. I was struck by the power and prowess of Princess Mkabayi (1750-1843). The elders were said to be speechless when she spoke. According to Shamase, a common Zulu expression which references Mkabayi’s well-known verbal skill is Umuntu ukhuluma kome umlomo, and translates as [like Mkabayi] the speaker speaks clearly and leaves no room for misunderstandings and misinterpretations. I found her to be a brilliant strategist with a servant heart and one whom history had not given due credit, and I was inspired to bring her story to life by setting it to music. I wanted to explore whether or not the events surrounding Mkabayi led to a change of consciousness among the Zulu nation, and I used this as a theme for my symphonic work about her. The lives of Queen Nandi (King Shaka’s mother) and Princess Mkabayi (King Shaka’s aunt) made for fascinating stories I had been privileged to discover, and I felt they were South African treasures to be elevated and shared with the world. The two works listed above form part of my repertoire based on Zulu royal history which are collectively known as “The Royal Trilogy,” and I have come to think of them as part of a developing “urban classical repertoire”. The Royal Trilogy is a set of three compositions with 33 independent scenes linking historical events and people. It includes the following entitled symphonic works for full orchestra: Nandi iNdlovukazi yezi Ndlovukazi (hereinafter “Queen Nandi”), Inkosazane Mkabayi (hereinafter “Princess Mkabayi”), and iNkosi uShaka: Umbono, Isizwe, Isiphetho - King Shaka: A Vision, A Nation, A Destiny (hereinafter “King Shaka”). Nandi premiered on 22 September 2016 as part of “A Musical Tribute Celebrating 200 Years of the Zulu Monarchy,” and “Mkabayi” premiered on 6 September 2018 under a programme titled “Princess Mkabayi: Celebrating Heritage Month”. Both pieces were performed at the Durban City Hall by the KwaZulu-Natal Philharmonic Orchestra with a mass Zulu choir (combination of the Clermont Community Choir, Prince Mshiyeni Choir, and Thokozani Choral Society) for socio-economic and ethnically diverse audiences. The final work, “King Shaka,” is expected to premiere in 2023. A future adaption of the Royal Trilogy is envisioned as an Afro Fusion Contemporary Ballet. , Thesis (MMus) -- Faculty of Humanities, Music & Musicology, 2023
- Full Text:
- Date Issued: 2023-04-10
- Authors: Bessey, Warren Gregory
- Date: 2023-04-10
- Subjects: Composition (Music) , Zulu (African people) Songs and music , Music Cross-cultural studies , uMkabayi kaJama , Nandi , Nobility South Africa Zululand History
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/404940 , vital:70123
- Description: Excerpt from Introduction: My interest in the Zulu royal family intensified as I began to read many stories and have lengthy conversations with members of the Zulu royal family and others, including Dr Maxwell Shamase (University of Zululand), about Zulu history. I was struck by the power and prowess of Princess Mkabayi (1750-1843). The elders were said to be speechless when she spoke. According to Shamase, a common Zulu expression which references Mkabayi’s well-known verbal skill is Umuntu ukhuluma kome umlomo, and translates as [like Mkabayi] the speaker speaks clearly and leaves no room for misunderstandings and misinterpretations. I found her to be a brilliant strategist with a servant heart and one whom history had not given due credit, and I was inspired to bring her story to life by setting it to music. I wanted to explore whether or not the events surrounding Mkabayi led to a change of consciousness among the Zulu nation, and I used this as a theme for my symphonic work about her. The lives of Queen Nandi (King Shaka’s mother) and Princess Mkabayi (King Shaka’s aunt) made for fascinating stories I had been privileged to discover, and I felt they were South African treasures to be elevated and shared with the world. The two works listed above form part of my repertoire based on Zulu royal history which are collectively known as “The Royal Trilogy,” and I have come to think of them as part of a developing “urban classical repertoire”. The Royal Trilogy is a set of three compositions with 33 independent scenes linking historical events and people. It includes the following entitled symphonic works for full orchestra: Nandi iNdlovukazi yezi Ndlovukazi (hereinafter “Queen Nandi”), Inkosazane Mkabayi (hereinafter “Princess Mkabayi”), and iNkosi uShaka: Umbono, Isizwe, Isiphetho - King Shaka: A Vision, A Nation, A Destiny (hereinafter “King Shaka”). Nandi premiered on 22 September 2016 as part of “A Musical Tribute Celebrating 200 Years of the Zulu Monarchy,” and “Mkabayi” premiered on 6 September 2018 under a programme titled “Princess Mkabayi: Celebrating Heritage Month”. Both pieces were performed at the Durban City Hall by the KwaZulu-Natal Philharmonic Orchestra with a mass Zulu choir (combination of the Clermont Community Choir, Prince Mshiyeni Choir, and Thokozani Choral Society) for socio-economic and ethnically diverse audiences. The final work, “King Shaka,” is expected to premiere in 2023. A future adaption of the Royal Trilogy is envisioned as an Afro Fusion Contemporary Ballet. , Thesis (MMus) -- Faculty of Humanities, Music & Musicology, 2023
- Full Text:
- Date Issued: 2023-04-10
Conceptualising mental distress from an African psychology paradigm: using an interpretative phenomenological analysis of the views of traditional healers
- Nabo-Bazana, Sandisiwe Sifanelwe
- Authors: Nabo-Bazana, Sandisiwe Sifanelwe
- Date: 2022-10-14
- Subjects: Healers South Africa , Traditional healer , Mental distress , Black psychology , Afrocentrism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406213 , vital:70249
- Description: With South Africa's long history of colonialism and racial oppression, there are still services in the country that many South Africans cannot relate to, including psychology. Research shows that many South Africans experience and are affected by mental distress due to several factors, including poverty, unemployment, and traumatic experiences. Managing and treating such distress has always been challenging for most South Africans. Some debates question the relevance of psychological services from the West in a South African context. This study explores other approaches to psychology that look beyond the Biopsychosocial model when dealing with certain types of disorders in an African context. African psychology, or the Afrocentric approach, looks at what is beneath the surface, not just the presenting problem. Mainstream psychology strives to be universal and applicable to all. However, African psychology disagrees with this notion. African psychology perceives human beings as strongly influenced by social and cultural influences. The focus of this approach includes the spiritual realm and the attached meanings. There is evidence for the need to merge Traditional and Western medicine. The research methodology for this study is qualitative, using Interpretative Phenomenological Analysis. IPA allows for a critical engagement with the ways in which participants construct their reality. The researcher carried out semi-structured interviews to enable participants, all traditional healers (3 female and 2 male), to narrate their experiences dealing with mentally distressed clients. The accounts of these traditional healers were analysed focusing on people who have experienced mental distress. From the analysis and synthesis of the themes, findings illustrate how traditional healers conceptualise and construct mental distress from an African Psychology paradigm. An emerging core theme was the importance of the divine call and its influence on the chosen treatments. More studies are needed to illustrate the potential for collaboration between African Traditional healing and EuroAmerican healing practices, to provide holistic services to people in need. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Nabo-Bazana, Sandisiwe Sifanelwe
- Date: 2022-10-14
- Subjects: Healers South Africa , Traditional healer , Mental distress , Black psychology , Afrocentrism
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406213 , vital:70249
- Description: With South Africa's long history of colonialism and racial oppression, there are still services in the country that many South Africans cannot relate to, including psychology. Research shows that many South Africans experience and are affected by mental distress due to several factors, including poverty, unemployment, and traumatic experiences. Managing and treating such distress has always been challenging for most South Africans. Some debates question the relevance of psychological services from the West in a South African context. This study explores other approaches to psychology that look beyond the Biopsychosocial model when dealing with certain types of disorders in an African context. African psychology, or the Afrocentric approach, looks at what is beneath the surface, not just the presenting problem. Mainstream psychology strives to be universal and applicable to all. However, African psychology disagrees with this notion. African psychology perceives human beings as strongly influenced by social and cultural influences. The focus of this approach includes the spiritual realm and the attached meanings. There is evidence for the need to merge Traditional and Western medicine. The research methodology for this study is qualitative, using Interpretative Phenomenological Analysis. IPA allows for a critical engagement with the ways in which participants construct their reality. The researcher carried out semi-structured interviews to enable participants, all traditional healers (3 female and 2 male), to narrate their experiences dealing with mentally distressed clients. The accounts of these traditional healers were analysed focusing on people who have experienced mental distress. From the analysis and synthesis of the themes, findings illustrate how traditional healers conceptualise and construct mental distress from an African Psychology paradigm. An emerging core theme was the importance of the divine call and its influence on the chosen treatments. More studies are needed to illustrate the potential for collaboration between African Traditional healing and EuroAmerican healing practices, to provide holistic services to people in need. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
Concerning Marya Schechtman’s narrative account
- Authors: Simuja, Clement
- Date: 2021-10-29
- Subjects: Schechtman, Marya, 1960- Criticism and interpretation , Narrative inquiry (Research method) , Identity (Psychology) , Identity (Philosophical concept) , Self , Individuality
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190748 , vital:45024
- Description: The persistence of personal identity stands at the heart of many human practices, such as paying individuals for their work or holding people responsible for their actions. As such, it seems important that theories of personal identity are able to account for the practical implications of continuity of personal identity. Mindful of the practical importance of personal identity, Marya Schechtman (1994) argues that her narrative view only accounts for the four features that persons must possess. Any account of personal identity is supposed to make persons capable of possessing these features. She then posits her narrative self-constitution view as an account of personal identity she feels is capable of explaining the link between personal identity and certain features of persons. In this thesis project, I present how the narrative views, as described by Schechtman and others, are interpretive enterprises and that this leads them to a potentially devastating conclusion. The narratives must be constructed from something, and I argue that it is memory. But empirical facts about memory do not allow for it to persist in a quantitative way, but rather in a qualitative way, much like persons. Upon making this argument, I further argue that if mainstream psychological views is correct, this reduces the persistence of memory to resemblance relations. And memory is the building blocks of narrative. If this is the case, then narrative is also reduced to resemblance relations. Narrative, therefore, does not persist through time in a non-qualitative way, and one is better off accepting a psychological theory by virtue of parsimony. Ultimately, I argue that Schechtman and narrative theorists may save narrative views by adopting what I call as a ‘causal narrative view’. A causal narrative view will encapsulate all of the relevant features of the typical narrative view, including the emphasis on construction, but will also add the addendum that narrative states must be placed in a causal relation to each other. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Simuja, Clement
- Date: 2021-10-29
- Subjects: Schechtman, Marya, 1960- Criticism and interpretation , Narrative inquiry (Research method) , Identity (Psychology) , Identity (Philosophical concept) , Self , Individuality
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/190748 , vital:45024
- Description: The persistence of personal identity stands at the heart of many human practices, such as paying individuals for their work or holding people responsible for their actions. As such, it seems important that theories of personal identity are able to account for the practical implications of continuity of personal identity. Mindful of the practical importance of personal identity, Marya Schechtman (1994) argues that her narrative view only accounts for the four features that persons must possess. Any account of personal identity is supposed to make persons capable of possessing these features. She then posits her narrative self-constitution view as an account of personal identity she feels is capable of explaining the link between personal identity and certain features of persons. In this thesis project, I present how the narrative views, as described by Schechtman and others, are interpretive enterprises and that this leads them to a potentially devastating conclusion. The narratives must be constructed from something, and I argue that it is memory. But empirical facts about memory do not allow for it to persist in a quantitative way, but rather in a qualitative way, much like persons. Upon making this argument, I further argue that if mainstream psychological views is correct, this reduces the persistence of memory to resemblance relations. And memory is the building blocks of narrative. If this is the case, then narrative is also reduced to resemblance relations. Narrative, therefore, does not persist through time in a non-qualitative way, and one is better off accepting a psychological theory by virtue of parsimony. Ultimately, I argue that Schechtman and narrative theorists may save narrative views by adopting what I call as a ‘causal narrative view’. A causal narrative view will encapsulate all of the relevant features of the typical narrative view, including the emphasis on construction, but will also add the addendum that narrative states must be placed in a causal relation to each other. , Thesis (MA) -- Faculty of Humanities, Philosophy, 2021
- Full Text:
- Date Issued: 2021-10-29
Constraints on Cr-PGE Mineralisation Models: Geochemical and petrological studies in the Middle Group 1 and 3 Chromitites, Western Limb, Bushveld Complex, South Africa
- Authors: Arunachellan, Yogendran
- Date: 2022-10-14
- Subjects: Chromite South Africa Bushveld Complex , Mineralogy South Africa Bushveld Complex , Geochemical surveys South Africa Bushveld Complex
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362730 , vital:65357
- Description: The Bushveld Complex in South Africa has been of interest in various research groups for decades, along with diverse theories regarding its origin, formation, and emplacement. These theories include magma mixing, contamination, and changes in the chamber's ephemeral parameters. Of interest for our current study is the formation of the middle group chromitite layers in the Western Limb. In this research, we aimed to determine the emplacement mechanism of the MG group chromitites by scrutinising the MG 1 and MG 3 layers. In core KD 151, the focus was placed on the MG 3 and MG 1 chromitite layers and their associated silicate rocks; on these regions of the core, time was spent for detailed observations. The differences and similarities of these layers were explored as the study advanced. The objectives were to determine the in-situ or proximal crystallisation of the chromitite by evaluating mineral textures and compositions. This required that we determine the characteristics of the immediate HW (hanging wall) and FW (footwall) to these chromitites, with insights into the relationship that anorthositic zones may offer and examine the PGE profiles of the chromitites in contrasting lithological settings. The sampled borehole was in the Western Limb of the Bushveld Complex; the immediate HW, chromitite layers and FW were divided into sections (2.5 x 5 cm) along selected horizons for a microscale study. The preliminary results of a study on the sub-economic Middle Group (MG) layers within the Critical Zone (CZ), contrasting the MG 1 (Lower CZ) and MG 3 (Upper CZ) chromitite layers of the Rustenburg Layered Suite of the Bushveld Complex, South Africa were analysed. The MG 3 and 1 suites of silicate rocks show disequilibrium textures between the pyroxenes and plagioclase, forming discontinuous olivine rims. These reaction rims are interpreted as products of magmatic aqueous fluid-facilitated reactions with minerals in a sub-solidus state. Deformation of the plagioclase was also noted in MG 1; this fracturing indicates either the transportation of these minerals or compaction by an overlying crystal mush. The MG 3 package of plagioclase, pyroxene and chromite compositions range from An67-78, En71-86 and Cr# of 68-84, respectively. The MG 1 package of plagioclase, pyroxene and chromite compositions are An64-91, En79-88 and Cr# of 70-80, respectively. The Cu/Pd ratio decreases from the base of the FW as it approaches the base of the chromitite, then remains low within the chromitite layer and finally increases upwards in the HW. These trends are observed in both the MG 3 and 1 package, therefore not influenced by the sulphide control. There is a decrease in both IPGE and PPGE upwards as the HW progresses into the chromitite. The FW levels of Ir and Ru increase upwards immediately adjacent to the FW contact, while Pd and Rh concentrations decrease. The whole-rock Mg# indicates a decrease in the MG 3 with a uniform increase in the HW and an erratic upward increase observed in the FW. The chondrite normalised PGE plots show a bell-shaped curve which is evident for the En content of the pyroxenes and the content of plagioclase with the highest values in the chromitite layer itself. The Cr# of the chromite decreases upwards with the highest values along the FW. The Cu/Pd ratio for MG 1 indicates chromitite control rather than sulphide control of the PGE. The whole-rock Mg# decreases in MG 1 with higher uniform values observed in the HW and FW. The geochemical and petrological data from the MG group study revealed that in situ fractional crystallisation seems unlikely as the sole mechanism for their formation in the CZ. A model is suggested in which the migration and transport of a magmatic slurry type suspension with accompanying hydrous fluids would likely have resulted in the emplacement of these chromitite packages along with the PGE mineralisation of the chromitites. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Arunachellan, Yogendran
- Date: 2022-10-14
- Subjects: Chromite South Africa Bushveld Complex , Mineralogy South Africa Bushveld Complex , Geochemical surveys South Africa Bushveld Complex
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/362730 , vital:65357
- Description: The Bushveld Complex in South Africa has been of interest in various research groups for decades, along with diverse theories regarding its origin, formation, and emplacement. These theories include magma mixing, contamination, and changes in the chamber's ephemeral parameters. Of interest for our current study is the formation of the middle group chromitite layers in the Western Limb. In this research, we aimed to determine the emplacement mechanism of the MG group chromitites by scrutinising the MG 1 and MG 3 layers. In core KD 151, the focus was placed on the MG 3 and MG 1 chromitite layers and their associated silicate rocks; on these regions of the core, time was spent for detailed observations. The differences and similarities of these layers were explored as the study advanced. The objectives were to determine the in-situ or proximal crystallisation of the chromitite by evaluating mineral textures and compositions. This required that we determine the characteristics of the immediate HW (hanging wall) and FW (footwall) to these chromitites, with insights into the relationship that anorthositic zones may offer and examine the PGE profiles of the chromitites in contrasting lithological settings. The sampled borehole was in the Western Limb of the Bushveld Complex; the immediate HW, chromitite layers and FW were divided into sections (2.5 x 5 cm) along selected horizons for a microscale study. The preliminary results of a study on the sub-economic Middle Group (MG) layers within the Critical Zone (CZ), contrasting the MG 1 (Lower CZ) and MG 3 (Upper CZ) chromitite layers of the Rustenburg Layered Suite of the Bushveld Complex, South Africa were analysed. The MG 3 and 1 suites of silicate rocks show disequilibrium textures between the pyroxenes and plagioclase, forming discontinuous olivine rims. These reaction rims are interpreted as products of magmatic aqueous fluid-facilitated reactions with minerals in a sub-solidus state. Deformation of the plagioclase was also noted in MG 1; this fracturing indicates either the transportation of these minerals or compaction by an overlying crystal mush. The MG 3 package of plagioclase, pyroxene and chromite compositions range from An67-78, En71-86 and Cr# of 68-84, respectively. The MG 1 package of plagioclase, pyroxene and chromite compositions are An64-91, En79-88 and Cr# of 70-80, respectively. The Cu/Pd ratio decreases from the base of the FW as it approaches the base of the chromitite, then remains low within the chromitite layer and finally increases upwards in the HW. These trends are observed in both the MG 3 and 1 package, therefore not influenced by the sulphide control. There is a decrease in both IPGE and PPGE upwards as the HW progresses into the chromitite. The FW levels of Ir and Ru increase upwards immediately adjacent to the FW contact, while Pd and Rh concentrations decrease. The whole-rock Mg# indicates a decrease in the MG 3 with a uniform increase in the HW and an erratic upward increase observed in the FW. The chondrite normalised PGE plots show a bell-shaped curve which is evident for the En content of the pyroxenes and the content of plagioclase with the highest values in the chromitite layer itself. The Cr# of the chromite decreases upwards with the highest values along the FW. The Cu/Pd ratio for MG 1 indicates chromitite control rather than sulphide control of the PGE. The whole-rock Mg# decreases in MG 1 with higher uniform values observed in the HW and FW. The geochemical and petrological data from the MG group study revealed that in situ fractional crystallisation seems unlikely as the sole mechanism for their formation in the CZ. A model is suggested in which the migration and transport of a magmatic slurry type suspension with accompanying hydrous fluids would likely have resulted in the emplacement of these chromitite packages along with the PGE mineralisation of the chromitites. , Thesis (MSc) -- Faculty of Science, Geology, 2022
- Full Text:
- Date Issued: 2022-10-14
Constructions of Ukuyalwa and marriage satisfaction: experiences of Xhosa couples in the Eastern Cape
- Authors: Bikwe, Siphuxolo
- Date: 2023-03-30
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408805 , vital:70527
- Description: Marital satisfaction may be described as the extent to which one’s expectations, desires and needs are being satisfied in their marriage. Studies that concern marital satisfaction provide us with crucial insights into factors that support or compromise the longevity of long-term, committed relationships. Little work has been done in understanding the role of cultural practices in marital satisfaction particularly in Africa, and South Africa more specifically. Ukuyalwa is a Xhosa ritual that takes place during a Xhosa traditional wedding, whereby the bride is introduced to the (traditional) guiding practices of her new home by the women of the family together with her sisters-in-law. This study informs the practice of African psychology as formulated by Ratele (2017b).Critical African psychology as a framework recognizes the construction of culture alongside political, socioeconomic, and historical matrices. These are acknowledged as an important element in psychological theories, methods, and explanations. This research project aimed to identify the discourses that circulate around ukuyalwa as a Xhosa cultural practice and consider the implications for the marital satisfaction of amaXhosa couples. The study interviewed 3 Xhosa couples of varying ages who had been married for different durations to develop an understanding of their experiences of ukuyalwa and marital satisfaction. Data was analyzed using a Foucauldian Discourse Analysis (FDA) which allowed for the identifications of the discourses that the couples used to construct ukuyalwa and marital satisfaction. The couples discursively constructed marriage as ‘divine unity’, ‘unification of families’ and ‘partnership’. Ukuyalwa was constructed as a ‘gendered process’, ideas of tradition and modernity, and a ‘foundation’ also became apparent. Satisfaction was constructed as ‘open communication’ and ‘work’. The couples’ positions shifted in their conversations, where in some instances they were 'learners’, ‘initiates’, and/or ‘passive’, and in other instances, they were ‘in charge’, ‘knowledgeable’, and ‘experts’. The discourses of culture, religion, and partnership circulated prominently in relation to marriage, ukuyalwa, and marital satisfaction. The findings of the study speak to how the couples’ constructions of marriage and cultural customs such as ukuyalwa are valuable as they often inform how couples behave in their marriage relationships and what they regard as satisfactory to them when it comes to marriage. These insights into what informs the couples’ ideas on marriage and satisfaction can be utilised in informing couples therapy interventions. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-03-30
- Authors: Bikwe, Siphuxolo
- Date: 2023-03-30
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408805 , vital:70527
- Description: Marital satisfaction may be described as the extent to which one’s expectations, desires and needs are being satisfied in their marriage. Studies that concern marital satisfaction provide us with crucial insights into factors that support or compromise the longevity of long-term, committed relationships. Little work has been done in understanding the role of cultural practices in marital satisfaction particularly in Africa, and South Africa more specifically. Ukuyalwa is a Xhosa ritual that takes place during a Xhosa traditional wedding, whereby the bride is introduced to the (traditional) guiding practices of her new home by the women of the family together with her sisters-in-law. This study informs the practice of African psychology as formulated by Ratele (2017b).Critical African psychology as a framework recognizes the construction of culture alongside political, socioeconomic, and historical matrices. These are acknowledged as an important element in psychological theories, methods, and explanations. This research project aimed to identify the discourses that circulate around ukuyalwa as a Xhosa cultural practice and consider the implications for the marital satisfaction of amaXhosa couples. The study interviewed 3 Xhosa couples of varying ages who had been married for different durations to develop an understanding of their experiences of ukuyalwa and marital satisfaction. Data was analyzed using a Foucauldian Discourse Analysis (FDA) which allowed for the identifications of the discourses that the couples used to construct ukuyalwa and marital satisfaction. The couples discursively constructed marriage as ‘divine unity’, ‘unification of families’ and ‘partnership’. Ukuyalwa was constructed as a ‘gendered process’, ideas of tradition and modernity, and a ‘foundation’ also became apparent. Satisfaction was constructed as ‘open communication’ and ‘work’. The couples’ positions shifted in their conversations, where in some instances they were 'learners’, ‘initiates’, and/or ‘passive’, and in other instances, they were ‘in charge’, ‘knowledgeable’, and ‘experts’. The discourses of culture, religion, and partnership circulated prominently in relation to marriage, ukuyalwa, and marital satisfaction. The findings of the study speak to how the couples’ constructions of marriage and cultural customs such as ukuyalwa are valuable as they often inform how couples behave in their marriage relationships and what they regard as satisfactory to them when it comes to marriage. These insights into what informs the couples’ ideas on marriage and satisfaction can be utilised in informing couples therapy interventions. , Thesis (MA) -- Faculty of Humanities, Psychology, 2023
- Full Text:
- Date Issued: 2023-03-30
Contextualising job satisfaction amongst lowest paid support staff in a Higher Education institution
- Madito, Gotlannamang Moloiesi Boipelo
- Authors: Madito, Gotlannamang Moloiesi Boipelo
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405984 , vital:70225
- Description: Thesis embargoed. To be relased in 2024. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
Contextualising job satisfaction amongst lowest paid support staff in a Higher Education institution
- Authors: Madito, Gotlannamang Moloiesi Boipelo
- Date: 2022-10-14
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/405984 , vital:70225
- Description: Thesis embargoed. To be relased in 2024. , Thesis (MA) -- Faculty of Humanities, Psychology, 2022
- Full Text:
- Date Issued: 2022-10-14
Controls of lateral and vertical variations in the geochemistry of the Hotazel Fe-Mn Formation at Nchwaning and Gloria mines, Kalahari Manganese Field, South Africa
- Authors: Dorbor Jr., Stephen Baysah
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424621 , vital:72169
- Description: The Paleoproterozoic Kalahari manganese field (KMF) in the Northern Cape Province, South Africa, hosts a large resource of manganese ores that has been of great interest over many decades. The Kalahari Manganese deposit (KMD), which is the largest of five erosional relics of the Hotazel Formation in the KMF, hosts three beds of Mn ores with alternating layers of banded iron formation (BIF) and hematite lutite. These three rock types are all evaluated for their mineralogy and geochemistry in this study, with emphasis on lateral and vertical distributions across the Gloria and Nchwaning Mines in the northernmost KMF, an area of high-grade, hydrothermally altered Mn mineralisation. The Mn ores of the Hotazel formation are traditionally categorised into two types. The carbonate-rich low Mn grade (Mn≤40 wt. %) ores (Mamatwan-type) domninates the largest part of the KMD, while carbonate-free, high Mn grade (Mn≥ 45 wt.%) ore (Wessels-type) occurs in the northernmost KMD. The Wessels-type ores are considered as the hydrothermally altered product of Mamatwan-type ores, and as indicated above, are the focus of this study. Five drill cores containing Wessels-type ores from the Nchwaning and Gloria area of the northern KMD were analysed to help understand the petrographic and particularly the geochemical variations in the Hotazel Fe-Mn Formation, both laterally for a given Mn layer of the three, and vertically across Mn layers as captured in specific drillcores. Petrographic and whole-rock geochemical results obtained from the three rock types of the Hotazel Formation show variations in their mineralogical and geochemical compositions, especially in the high-grade Mn ores themselves. Most of the samples of the BIFs layers are dominated by hematite and chert occurring in banded fashion, which is typical of a normal carbonate-free altered BIF discussed in this thesis. The BIFs can also be locally enriched in hematite (ferruginised), occurring as massive hematite ores usually at the top of the stratigraphic profiles. The presence of aegirine-rich assemblages is also noted occurring in some of the BIF and hematite lutite sections immediately above and below the Mn ore beds. The high-grade Mn ore beds vary greatly in mineralogy and texture of the ores laterally and even within a single drill core. In an extreme case, a single drillcore sampled from the Gloria mine (GL57) contains high-grade Wessels-type ore in the upper Mn bed and low-grade, Mamatwan-type ore in the lower Mn layer. Geochemically, the Mn ore bodies also show substantial geochemical variability, although a net increase in the Mn grade downward is usually characterised by a corresponding depletion in mainly bulk Ca, Si and carbonate. However, the Fe content appears to be consistently higher in the upper ore bodies of the drillcores than the lower ones, and the increase in the concentration of the Fe-oxide expectedly causes a relative decrease in the bulk Mn-oxide concentration, usually expressed as an antithetic relationship between the two elements. In terms of trace element distributions, this appears to be more significant in the Mn ores than the other two rock types affected by the same alteration process, probably due to the presence of Mn phases such as hausmannite and braunite serving as good hosts to several trace elements. Cu, Zn, Pb and to a lesser extent Mo are trace metals that appear to show elevated concentration levels (net enrichments) in high-grade Mn ore by comparison to the presumed Mamatwan-type protolith. Ba is an additional element of clear enrichment, manifested mainly as the mineral barite. The Northern KMD has a complex post-depositional history, which includes the intrusion of NE-SW-trending dykes, formation of the Mapedi/Gamagara erosional unconformity, normal faulting associated with the Wessels event and major thrust faults in the western part of the northern KMD. These structural events all have the potential to have contributed to the alteration and subsequent enrichment of the Mn ores in the Nchwaning and Gloria area. As such, the mineralogical, textural, and geochemical variations observed here can tentatively be attributed to the different structural features in the northern KMD. Classic interpretations suggest that normal N-S-trending fault structures have acted as fluid conduits for hydrothermal fluids, which led to the metasomatic alteration of the Mn ore body laterally. Drill cores proximal to and evidently affected by fault-controlled alteration in the SE and SW-portions of the Nchwaning area, have comparable mineralogical and geochemical characteristics for both ore bodies (upper and lower) with subdued alteration effects from the unconformed contact above. Fluids associated with the Mapedi/Gamagara unconformity, would have percolated down-stratigraphy causing oxidative ferruginisation, which led to the formation of massive hematite ores in the top BIF layers and ferruginised Mn ores in the Mn ore beds. This alteration effect appears more prominent in a drill core from the northern part of the study area where the unconformity contact appears more proximal to the upper Mn bed. Drill cores located in the western part of the Nchwaning area seem to also capture evidence of fluid alteration with enrichment in Na recorded in the local abundance of the mineral aegirine. Finally, the dyke structures appear to have acted as impermeable fluid barriers to both lateral and possibly down-dip fluid-flow. , Thesis (MSc) -- Faculty of Science, Geology, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Dorbor Jr., Stephen Baysah
- Date: 2023-10-13
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424621 , vital:72169
- Description: The Paleoproterozoic Kalahari manganese field (KMF) in the Northern Cape Province, South Africa, hosts a large resource of manganese ores that has been of great interest over many decades. The Kalahari Manganese deposit (KMD), which is the largest of five erosional relics of the Hotazel Formation in the KMF, hosts three beds of Mn ores with alternating layers of banded iron formation (BIF) and hematite lutite. These three rock types are all evaluated for their mineralogy and geochemistry in this study, with emphasis on lateral and vertical distributions across the Gloria and Nchwaning Mines in the northernmost KMF, an area of high-grade, hydrothermally altered Mn mineralisation. The Mn ores of the Hotazel formation are traditionally categorised into two types. The carbonate-rich low Mn grade (Mn≤40 wt. %) ores (Mamatwan-type) domninates the largest part of the KMD, while carbonate-free, high Mn grade (Mn≥ 45 wt.%) ore (Wessels-type) occurs in the northernmost KMD. The Wessels-type ores are considered as the hydrothermally altered product of Mamatwan-type ores, and as indicated above, are the focus of this study. Five drill cores containing Wessels-type ores from the Nchwaning and Gloria area of the northern KMD were analysed to help understand the petrographic and particularly the geochemical variations in the Hotazel Fe-Mn Formation, both laterally for a given Mn layer of the three, and vertically across Mn layers as captured in specific drillcores. Petrographic and whole-rock geochemical results obtained from the three rock types of the Hotazel Formation show variations in their mineralogical and geochemical compositions, especially in the high-grade Mn ores themselves. Most of the samples of the BIFs layers are dominated by hematite and chert occurring in banded fashion, which is typical of a normal carbonate-free altered BIF discussed in this thesis. The BIFs can also be locally enriched in hematite (ferruginised), occurring as massive hematite ores usually at the top of the stratigraphic profiles. The presence of aegirine-rich assemblages is also noted occurring in some of the BIF and hematite lutite sections immediately above and below the Mn ore beds. The high-grade Mn ore beds vary greatly in mineralogy and texture of the ores laterally and even within a single drill core. In an extreme case, a single drillcore sampled from the Gloria mine (GL57) contains high-grade Wessels-type ore in the upper Mn bed and low-grade, Mamatwan-type ore in the lower Mn layer. Geochemically, the Mn ore bodies also show substantial geochemical variability, although a net increase in the Mn grade downward is usually characterised by a corresponding depletion in mainly bulk Ca, Si and carbonate. However, the Fe content appears to be consistently higher in the upper ore bodies of the drillcores than the lower ones, and the increase in the concentration of the Fe-oxide expectedly causes a relative decrease in the bulk Mn-oxide concentration, usually expressed as an antithetic relationship between the two elements. In terms of trace element distributions, this appears to be more significant in the Mn ores than the other two rock types affected by the same alteration process, probably due to the presence of Mn phases such as hausmannite and braunite serving as good hosts to several trace elements. Cu, Zn, Pb and to a lesser extent Mo are trace metals that appear to show elevated concentration levels (net enrichments) in high-grade Mn ore by comparison to the presumed Mamatwan-type protolith. Ba is an additional element of clear enrichment, manifested mainly as the mineral barite. The Northern KMD has a complex post-depositional history, which includes the intrusion of NE-SW-trending dykes, formation of the Mapedi/Gamagara erosional unconformity, normal faulting associated with the Wessels event and major thrust faults in the western part of the northern KMD. These structural events all have the potential to have contributed to the alteration and subsequent enrichment of the Mn ores in the Nchwaning and Gloria area. As such, the mineralogical, textural, and geochemical variations observed here can tentatively be attributed to the different structural features in the northern KMD. Classic interpretations suggest that normal N-S-trending fault structures have acted as fluid conduits for hydrothermal fluids, which led to the metasomatic alteration of the Mn ore body laterally. Drill cores proximal to and evidently affected by fault-controlled alteration in the SE and SW-portions of the Nchwaning area, have comparable mineralogical and geochemical characteristics for both ore bodies (upper and lower) with subdued alteration effects from the unconformed contact above. Fluids associated with the Mapedi/Gamagara unconformity, would have percolated down-stratigraphy causing oxidative ferruginisation, which led to the formation of massive hematite ores in the top BIF layers and ferruginised Mn ores in the Mn ore beds. This alteration effect appears more prominent in a drill core from the northern part of the study area where the unconformity contact appears more proximal to the upper Mn bed. Drill cores located in the western part of the Nchwaning area seem to also capture evidence of fluid alteration with enrichment in Na recorded in the local abundance of the mineral aegirine. Finally, the dyke structures appear to have acted as impermeable fluid barriers to both lateral and possibly down-dip fluid-flow. , Thesis (MSc) -- Faculty of Science, Geology, 2023
- Full Text:
- Date Issued: 2023-10-13
Corporate failure and ethical resources: a case study of Steinhoff and Carillion
- Authors: Mthombeni, Seyijeni Koos
- Date: 2023-10-13
- Subjects: Corporate governance , Business ethics , Steinhoff International (Firm) Corrupt practices , Carillion (Firm) Corrupt practices , Business failures , Accounting fraud
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/419165 , vital:71621
- Description: This study aimed to investigate the impact of disregarding ethical resources on company performance, with a particular focus on Carillion and Steinhoff as case studies. A pragmatist research philosophy was employed using a mixed methods approach, utilizing deductive inferencing to produce archival research. Data was collected from annual financial statements and existing literature on Steinhoff and Carillion's corporate failures. Both content analysis and statistical analysis were employed to analyse the data. The study found that both Carillion and Steinhoff were at the top of their respective industries when they began to underperform due to poor governance. On the part of Carillion, much of its failure can be attributed to aggressive bidding, while for Steinhoff, its failure was due to unscrupulous accounting practices. Corruption and fraud at the top echelon of each of these respective companies began to trickle down to the bottom of the hierarchy. Additionally, Steinhoff used a two-tier board system that promotes information asymmetry between a management board and a supervisory board. This gave Steinhoff’s management board leverage to manipulate company reports and hide information from the supervisory board. Steinhoff equally violated the board’s independence by making former management executives part of the supervisory board, who could potentially be lenient to the management board due to past relationships. This was further exacerbated by the CEO duality, which contributed to Steinhoff’s lack of board independence. Furthermore, Steinhoff’s board was reported to have served as board members for a long time, eventually leading them to create a group culture that negatively affected its board’s independence. Different from Steinhoff, which lacked board independence and board diversity, at face value, Carillion appeared to have a predominantly independent board with diverse experience and external commitments. However, Carillion also lacked board independence in a different way, as some of its board members were previously employed by KPMG. KPMG was also the external auditor of Carillion. This created a scenario where Carillion and KPMG were conniving, which may have affected the objectivity of the external audits on financial performance. Further to this, the CEO held outsized power over the board, which could have also resulted in a lack of independence. This, in turn, facilitated corrupt behaviour within the organisation, which may have contributed to its corporate failure. iv The findings of the study highlight the following three conclusions: i) profits that are premised on reckless, irregular, and fraudulent business and accounting practices are not sustainable; ii) governance structures that do not adhere to sound corporate governance principles result in impaired board independence and negatively affect firm performance; and iii) companies that reach the pinnacle of their success through unethical conduct are ultimately short-lived. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Mthombeni, Seyijeni Koos
- Date: 2023-10-13
- Subjects: Corporate governance , Business ethics , Steinhoff International (Firm) Corrupt practices , Carillion (Firm) Corrupt practices , Business failures , Accounting fraud
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/419165 , vital:71621
- Description: This study aimed to investigate the impact of disregarding ethical resources on company performance, with a particular focus on Carillion and Steinhoff as case studies. A pragmatist research philosophy was employed using a mixed methods approach, utilizing deductive inferencing to produce archival research. Data was collected from annual financial statements and existing literature on Steinhoff and Carillion's corporate failures. Both content analysis and statistical analysis were employed to analyse the data. The study found that both Carillion and Steinhoff were at the top of their respective industries when they began to underperform due to poor governance. On the part of Carillion, much of its failure can be attributed to aggressive bidding, while for Steinhoff, its failure was due to unscrupulous accounting practices. Corruption and fraud at the top echelon of each of these respective companies began to trickle down to the bottom of the hierarchy. Additionally, Steinhoff used a two-tier board system that promotes information asymmetry between a management board and a supervisory board. This gave Steinhoff’s management board leverage to manipulate company reports and hide information from the supervisory board. Steinhoff equally violated the board’s independence by making former management executives part of the supervisory board, who could potentially be lenient to the management board due to past relationships. This was further exacerbated by the CEO duality, which contributed to Steinhoff’s lack of board independence. Furthermore, Steinhoff’s board was reported to have served as board members for a long time, eventually leading them to create a group culture that negatively affected its board’s independence. Different from Steinhoff, which lacked board independence and board diversity, at face value, Carillion appeared to have a predominantly independent board with diverse experience and external commitments. However, Carillion also lacked board independence in a different way, as some of its board members were previously employed by KPMG. KPMG was also the external auditor of Carillion. This created a scenario where Carillion and KPMG were conniving, which may have affected the objectivity of the external audits on financial performance. Further to this, the CEO held outsized power over the board, which could have also resulted in a lack of independence. This, in turn, facilitated corrupt behaviour within the organisation, which may have contributed to its corporate failure. iv The findings of the study highlight the following three conclusions: i) profits that are premised on reckless, irregular, and fraudulent business and accounting practices are not sustainable; ii) governance structures that do not adhere to sound corporate governance principles result in impaired board independence and negatively affect firm performance; and iii) companies that reach the pinnacle of their success through unethical conduct are ultimately short-lived. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2023
- Full Text:
- Date Issued: 2023-10-13