VIVA Comrade Moss
- NUMSA
- Authors: NUMSA
- Date: 25 April
- Subjects: NUMSA
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/109640 , vital:33163 , SALHA 14b : NUMSA
- Description: The last 'Trial Update" reported on Comrade Moss’s case until mid-March. This report covers the period from that time up until 25th April.STADLER - "ANC EXPERT" Brigadier Stadler testified that the ANC had made certain calls to organisations within the country which, according to his "research", had been followed by organisations in the country. As examples he gave the ANC’s call for ungovernability, the formation of organs of people’s power and the destruction of town councils. During cross-examination Stadler conceded that he was not able to give examples of any direct link between the ANC and organisations inside the coutry but he said an inference could be drawn by looking at the ANC’s call and the behaviour of organisations inside the country.
- Full Text:
- Authors: NUMSA
- Date: 25 April
- Subjects: NUMSA
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/109640 , vital:33163 , SALHA 14b : NUMSA
- Description: The last 'Trial Update" reported on Comrade Moss’s case until mid-March. This report covers the period from that time up until 25th April.STADLER - "ANC EXPERT" Brigadier Stadler testified that the ANC had made certain calls to organisations within the country which, according to his "research", had been followed by organisations in the country. As examples he gave the ANC’s call for ungovernability, the formation of organs of people’s power and the destruction of town councils. During cross-examination Stadler conceded that he was not able to give examples of any direct link between the ANC and organisations inside the coutry but he said an inference could be drawn by looking at the ANC’s call and the behaviour of organisations inside the country.
- Full Text:
Honorary Citation for the Conferment of Doctor of Laws honoris causa - Tandabantu Tennyson August
- Rhodes University, Martin, Tom
- Authors: Rhodes University , Martin, Tom
- Date: 2024-14-05
- Subjects: Uncatalogued
- Language: English
- Type: Speeches , Transcripts, speech , text
- Identifier: http://hdl.handle.net/10962/432591 , vital:72885
- Description: Rhodes University Honorary Doctorate Citation (5 April 2024) Tandabantu Tennyson August: 1980s. South Africa. In the Bantustans of the time, like the Transkei, the youth have little reason for hope. They have much reason for despair. Their choices seem limited to the politics of struggle or to crime, an attempt to gain some kind of advantage from the meagre and unacceptable options on offer. In those bleak times, what was needed was visionaries. People who could see beyond the current circumstances to a different future and imagine how best to prepare for it. Not as idealists, but as pragmatists. What would happen once circumstances change, once the struggle had succeeded? Would we be ready for it? What qualities would the youth need to have in order to both benefit from and participate in a new dispensation? One such visionary was Tandabantu Tennyson August, and it is my distinct pleasure to have the opportunity to tell you more about him. Born in 1948, Mr. August matriculated from Healdtown High School, before pursuing higher education at the University of Transkei, where obtained a Bachelor of Arts degree majoring in English and Geography. This was followed by Comparative Curriculum Studies at the University of South Africa, alongside obtaining teaching certificates from Lovedale and Cicira teacher training colleges, with majors in Physical Science, Mathematics, Science, and Mathematics. This solid educational foundation laid the groundwork for his impactful career in education. He taught at Wongalethu High, St Johns College and was deputy principal at Norwood, before taking up his first principalship, at Thanga High School in 1980. From 1984 to 1990 he was principal of Ndamase High School. During his tenure there, the matric pass rate never fell below 90%. From 1991 to 1995 he was principal Isivivane High School during which time the school was promoted from a primary to a high school. Following his distinguished service at schools, he worked at the Eastern Cape Department of Basic Education, first as a deputy chief education specialist (1996 – 2006) and then as chief education specialist (2006-2010). During that time, he played a pivotal role in establishing (in conjunction with Rhodes University) and being the provincial coordinator the Advanced Certificate in Education in English, followed by ACEs in mathematical literacy and life orientation. In 2016 he received a provincial teaching award for excellence. In 2017 he was awarded the Kade Asmal award for excellence in teaching. To this day, he remains an Executive member of the eastern cape Education advisory council. Quite a career. But there’s something I haven’t mentioned. He was also an accomplished rugby player of international standing. While at Lovedale College, he was selected to represent Border and then the South African African Rugby Board, playing England in Gqeberha in 1972, in a team that would later be known as the black springboks. He eventually received his green and gold springbok blazer as just recognition of his achievement. He incorporated his love of sport into his vision for the youth under his care, as part of his overriding mission of educating the whole person. He got everyone involved in sport, if not as a player, then as a supporter. Especially during his time as principal of Ndamase High School, I am led to believe, it was extremely intimidating for opposing teams to play them. Not only at Ndamase home games, but especially at their away games. There would be one bus for the team players, and six buses for the supporters. From 1986 – 1990: he was president of the Transkei schools` sports union (TSSU). But there’s yet another thing I haven’t mentioned. In 1981, just as his career as an educational leader was really taking off, he was involved in a terrible motor vehicle accident. It left him permanently disabled and, for much of his life, a wheelchair user. Rather than stopping him, it simply added another string to his bow, now as an advocate for the disabled. From 2012 – 2022: Chairperson Eastern Cape South African National Association For Special Education (SANASE): this organization cater for the education and wellbeing of learners with disabilities and special needs. In 2023, he was the national deputy president of the same organisation. From 2013 – to date: he is a Board Member on the National Council of & for persons with disabilities (NCPD). I had the pleasure of an extensive conversation with one of Mr August’s former pupils at Ndamase High, Professor Deyi Mbelani, the current director of Rhodes University’s Institute for the Study of Englishes in Africa. He told me many stories about Mr August’s leadership, that I only wish I had time to share with you now. I put it to Professor Mbelani that, having read about Mr August, the word that stood out for me was “dedication.” He agreed that “dedication” was the word, but that I must not leave out another: “vision”. It is Mr August’s status as a visionary that best defines him, he said. Going back over the above, I think he is right. Mr Chancellor I have the honour to request you to confer the degree of Doctor of Laws honoris causa on the Mr Tandabantu Tennyson August. *The above citation draws heavily on documents submitted as part of the honorary doctorate nomination process and others compiled by the Division of Communications and Advancement. - Tom Martin.
- Full Text:
- Authors: Rhodes University , Martin, Tom
- Date: 2024-14-05
- Subjects: Uncatalogued
- Language: English
- Type: Speeches , Transcripts, speech , text
- Identifier: http://hdl.handle.net/10962/432591 , vital:72885
- Description: Rhodes University Honorary Doctorate Citation (5 April 2024) Tandabantu Tennyson August: 1980s. South Africa. In the Bantustans of the time, like the Transkei, the youth have little reason for hope. They have much reason for despair. Their choices seem limited to the politics of struggle or to crime, an attempt to gain some kind of advantage from the meagre and unacceptable options on offer. In those bleak times, what was needed was visionaries. People who could see beyond the current circumstances to a different future and imagine how best to prepare for it. Not as idealists, but as pragmatists. What would happen once circumstances change, once the struggle had succeeded? Would we be ready for it? What qualities would the youth need to have in order to both benefit from and participate in a new dispensation? One such visionary was Tandabantu Tennyson August, and it is my distinct pleasure to have the opportunity to tell you more about him. Born in 1948, Mr. August matriculated from Healdtown High School, before pursuing higher education at the University of Transkei, where obtained a Bachelor of Arts degree majoring in English and Geography. This was followed by Comparative Curriculum Studies at the University of South Africa, alongside obtaining teaching certificates from Lovedale and Cicira teacher training colleges, with majors in Physical Science, Mathematics, Science, and Mathematics. This solid educational foundation laid the groundwork for his impactful career in education. He taught at Wongalethu High, St Johns College and was deputy principal at Norwood, before taking up his first principalship, at Thanga High School in 1980. From 1984 to 1990 he was principal of Ndamase High School. During his tenure there, the matric pass rate never fell below 90%. From 1991 to 1995 he was principal Isivivane High School during which time the school was promoted from a primary to a high school. Following his distinguished service at schools, he worked at the Eastern Cape Department of Basic Education, first as a deputy chief education specialist (1996 – 2006) and then as chief education specialist (2006-2010). During that time, he played a pivotal role in establishing (in conjunction with Rhodes University) and being the provincial coordinator the Advanced Certificate in Education in English, followed by ACEs in mathematical literacy and life orientation. In 2016 he received a provincial teaching award for excellence. In 2017 he was awarded the Kade Asmal award for excellence in teaching. To this day, he remains an Executive member of the eastern cape Education advisory council. Quite a career. But there’s something I haven’t mentioned. He was also an accomplished rugby player of international standing. While at Lovedale College, he was selected to represent Border and then the South African African Rugby Board, playing England in Gqeberha in 1972, in a team that would later be known as the black springboks. He eventually received his green and gold springbok blazer as just recognition of his achievement. He incorporated his love of sport into his vision for the youth under his care, as part of his overriding mission of educating the whole person. He got everyone involved in sport, if not as a player, then as a supporter. Especially during his time as principal of Ndamase High School, I am led to believe, it was extremely intimidating for opposing teams to play them. Not only at Ndamase home games, but especially at their away games. There would be one bus for the team players, and six buses for the supporters. From 1986 – 1990: he was president of the Transkei schools` sports union (TSSU). But there’s yet another thing I haven’t mentioned. In 1981, just as his career as an educational leader was really taking off, he was involved in a terrible motor vehicle accident. It left him permanently disabled and, for much of his life, a wheelchair user. Rather than stopping him, it simply added another string to his bow, now as an advocate for the disabled. From 2012 – 2022: Chairperson Eastern Cape South African National Association For Special Education (SANASE): this organization cater for the education and wellbeing of learners with disabilities and special needs. In 2023, he was the national deputy president of the same organisation. From 2013 – to date: he is a Board Member on the National Council of & for persons with disabilities (NCPD). I had the pleasure of an extensive conversation with one of Mr August’s former pupils at Ndamase High, Professor Deyi Mbelani, the current director of Rhodes University’s Institute for the Study of Englishes in Africa. He told me many stories about Mr August’s leadership, that I only wish I had time to share with you now. I put it to Professor Mbelani that, having read about Mr August, the word that stood out for me was “dedication.” He agreed that “dedication” was the word, but that I must not leave out another: “vision”. It is Mr August’s status as a visionary that best defines him, he said. Going back over the above, I think he is right. Mr Chancellor I have the honour to request you to confer the degree of Doctor of Laws honoris causa on the Mr Tandabantu Tennyson August. *The above citation draws heavily on documents submitted as part of the honorary doctorate nomination process and others compiled by the Division of Communications and Advancement. - Tom Martin.
- Full Text:
A decision support tool for equitable and sustainable water management in the Koue Bokkeveld
- Authors: Tholanah, Rodney
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464344 , vital:76503
- Description: Water is an important natural resource with multiple domestic and industrial uses. South Africa has a water scarcity problem, with domestic and industrial demand projected to increase due to population growth. One affected area is the Koue Bokkeveld (KBV), an agricultural catchment in the Western Cape. Water scarcity, especially in the summer, can cause conflicts among the farmers. This study sought to determine the extent to which Agent-Based (AB) modelling could be used to model the KBV catchment area and simulate future climate and usage scenarios. The study used the ComMod methodology as it allows stakeholders to be involved at each step of the modelling process, thus improving the model’s credibility as a decision-support tool (DST). The model was implemented using Cormas, an Agent-Based Model (ABM) implementation framework built with the Smalltalk language. The model was verified and validated through consultations with the catchment coordinator and through workshops with stakeholders. The ABM reflected the catchment characteristics. Farms known to have water shortages had water shortages in the ABM. However, there was one that did not have shortages, which is attributed to land use change. The ABM was used to run multiple simulation scenarios, and it provides simulation results at the crop field, farm and catchment levels, which allows the ABM to be used as a bottom-up DST. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
- Authors: Tholanah, Rodney
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464344 , vital:76503
- Description: Water is an important natural resource with multiple domestic and industrial uses. South Africa has a water scarcity problem, with domestic and industrial demand projected to increase due to population growth. One affected area is the Koue Bokkeveld (KBV), an agricultural catchment in the Western Cape. Water scarcity, especially in the summer, can cause conflicts among the farmers. This study sought to determine the extent to which Agent-Based (AB) modelling could be used to model the KBV catchment area and simulate future climate and usage scenarios. The study used the ComMod methodology as it allows stakeholders to be involved at each step of the modelling process, thus improving the model’s credibility as a decision-support tool (DST). The model was implemented using Cormas, an Agent-Based Model (ABM) implementation framework built with the Smalltalk language. The model was verified and validated through consultations with the catchment coordinator and through workshops with stakeholders. The ABM reflected the catchment characteristics. Farms known to have water shortages had water shortages in the ABM. However, there was one that did not have shortages, which is attributed to land use change. The ABM was used to run multiple simulation scenarios, and it provides simulation results at the crop field, farm and catchment levels, which allows the ABM to be used as a bottom-up DST. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
A review of African praying mantises (Dictyoptera: Mantodea) incorporating molecular and morphological data
- Authors: Roestof, Bruce
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464428 , vital:76510
- Description: Praying mantises (Dictyoptera: Mantodea) are an iconic group of predatory insects, comprising around 2500 species globally, that occur in all zoogeographic regions except the poles. Their presence in the social psyche of many cultures has existed for millennia, but until the past decade, Mantodea has received little attention from the scientific community as the constituent species are of little economic or medical importance. Africa is rich in praying mantis diversity, accounting for approximately 45% of all described species, yet it remains largely under-sampled compared to the New World and Asian regions. Recent exploration of Gabon and Central African Republic have proved fruitful, with new species descriptions being major highlights. A recent re-cataloguing of southern African praying mantises has proved useful as specimen identifications were checked, new distributions were recorded, and most importantly, it was revealed that museum collections have significantly more diversity than previously recorded. A meta-analysis of African praying mantises was conducted; we present a species checklist to the countries of Africa, including Madagascar and surrounding islands. Currently, 17 families, 182 genera, and 1104 species occur in Africa.Historically, the classification of praying mantises was based solely on morphological features, and the novelty of the field at the time made it unclear which characteristics were of taxonomic importance. The onset of molecular systematics brought attention to incongruences between morphological and molecular phylogenies, believed to be attributed to convergent evolution masking the underlying evolutionary processes that occurred. Significant progress has been made in the past two decades regarding Mantodean classification and most described genera have their phylogenetic position. With the addition of more African taxa, we present mantodean phylogenies for molecular and morphological data. Molecular phylogenies were estimated through Bayesian Inference and Maximum Likelihood analyses using two nuclear (28S and H3) and two mitochondrial markers (16S and COI) for 210 individuals that represented 24 of the 29 families globally. Morphological phylogenies were estimated through Maximum Likelihood analyses of a morphological data matrix comprising 149 characters for 248 individuals that represent 24 families. The same data matrix was used to produce a key to all African mantodean families, accompanied by their descriptions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Authors: Roestof, Bruce
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464428 , vital:76510
- Description: Praying mantises (Dictyoptera: Mantodea) are an iconic group of predatory insects, comprising around 2500 species globally, that occur in all zoogeographic regions except the poles. Their presence in the social psyche of many cultures has existed for millennia, but until the past decade, Mantodea has received little attention from the scientific community as the constituent species are of little economic or medical importance. Africa is rich in praying mantis diversity, accounting for approximately 45% of all described species, yet it remains largely under-sampled compared to the New World and Asian regions. Recent exploration of Gabon and Central African Republic have proved fruitful, with new species descriptions being major highlights. A recent re-cataloguing of southern African praying mantises has proved useful as specimen identifications were checked, new distributions were recorded, and most importantly, it was revealed that museum collections have significantly more diversity than previously recorded. A meta-analysis of African praying mantises was conducted; we present a species checklist to the countries of Africa, including Madagascar and surrounding islands. Currently, 17 families, 182 genera, and 1104 species occur in Africa.Historically, the classification of praying mantises was based solely on morphological features, and the novelty of the field at the time made it unclear which characteristics were of taxonomic importance. The onset of molecular systematics brought attention to incongruences between morphological and molecular phylogenies, believed to be attributed to convergent evolution masking the underlying evolutionary processes that occurred. Significant progress has been made in the past two decades regarding Mantodean classification and most described genera have their phylogenetic position. With the addition of more African taxa, we present mantodean phylogenies for molecular and morphological data. Molecular phylogenies were estimated through Bayesian Inference and Maximum Likelihood analyses using two nuclear (28S and H3) and two mitochondrial markers (16S and COI) for 210 individuals that represented 24 of the 29 families globally. Morphological phylogenies were estimated through Maximum Likelihood analyses of a morphological data matrix comprising 149 characters for 248 individuals that represent 24 families. The same data matrix was used to produce a key to all African mantodean families, accompanied by their descriptions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
An analysis of tax incentives offered for investments by individuals in South Africa and the United Kingdom
- Authors: Muzenda, Nokuthula Tafadzwa
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463516 , vital:76416
- Description: This research analysed the tax incentives available for investments by individuals in South Africa and compared them to investments in the United Kingdom. It answered the question whether, based on incentives provided in the United Kingdom, recommendations can be made for investment incentives to be implemented in South Africa. The type of investments described were venture capital schemes, tax-free investments, retirement savings, endowment policies, purchased annuities, workplace investment schemes, and fixed interest bonds. These classes of investments were discussed together with the tax incentives offered for them in South Africa and the United Kingdom. An interpretative paradigm was adopted for this research, together with a doctrinal methodology and a qualitative method. This research analysed the legislative provisions in South Africa and the United Kingdom. Information was also collected from secondary sources such as textbooks and articles written on investments and taxes. There were no ethical considerations in this research as the data that was used are publicly available. The tax incentive provisions in South Africa have not proven to be effective in increasing household savings, which remain low. The comparison of the taxes and incentives in South Africa and the United Kingdom indicated that there are some similarities on how certain investments are taxed, but for most types of investments, the United Kingdom provided more favourable tax incentives than South Africa. Recommendations were made for the venture capital company incentive previously applying to be reinstated, or to introduce some form of income tax and capital gains tax relief for direct investment into venture capital companies. The removal of the penalty for tax-free investments in excess of the maximum permitted was recommended, and to charge income tax according to the tax tables on contributions exceeding the limit. With regard to purchased annuities, it was recommended that no income tax should apply to annuities received in the case of disability, sickness, and similar circumstances. For the section 8B Broad-Based Share Incentive Scheme recommendations were made to not levy dividends tax on cash dividends retained for reinvestment into the scheme, and for employees not to be liable for income tax when shares are disposed of, where they are no longer in the relevant employment due to circumstances beyond their control. A recommendation was also made to consider introducing workplace savings schemes similar to the savings schemes applying in the United Kingdom. An education campaign by the South African Revenue Service was recommended, to inform the public of investment incentives. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2024
- Full Text:
- Authors: Muzenda, Nokuthula Tafadzwa
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463516 , vital:76416
- Description: This research analysed the tax incentives available for investments by individuals in South Africa and compared them to investments in the United Kingdom. It answered the question whether, based on incentives provided in the United Kingdom, recommendations can be made for investment incentives to be implemented in South Africa. The type of investments described were venture capital schemes, tax-free investments, retirement savings, endowment policies, purchased annuities, workplace investment schemes, and fixed interest bonds. These classes of investments were discussed together with the tax incentives offered for them in South Africa and the United Kingdom. An interpretative paradigm was adopted for this research, together with a doctrinal methodology and a qualitative method. This research analysed the legislative provisions in South Africa and the United Kingdom. Information was also collected from secondary sources such as textbooks and articles written on investments and taxes. There were no ethical considerations in this research as the data that was used are publicly available. The tax incentive provisions in South Africa have not proven to be effective in increasing household savings, which remain low. The comparison of the taxes and incentives in South Africa and the United Kingdom indicated that there are some similarities on how certain investments are taxed, but for most types of investments, the United Kingdom provided more favourable tax incentives than South Africa. Recommendations were made for the venture capital company incentive previously applying to be reinstated, or to introduce some form of income tax and capital gains tax relief for direct investment into venture capital companies. The removal of the penalty for tax-free investments in excess of the maximum permitted was recommended, and to charge income tax according to the tax tables on contributions exceeding the limit. With regard to purchased annuities, it was recommended that no income tax should apply to annuities received in the case of disability, sickness, and similar circumstances. For the section 8B Broad-Based Share Incentive Scheme recommendations were made to not levy dividends tax on cash dividends retained for reinvestment into the scheme, and for employees not to be liable for income tax when shares are disposed of, where they are no longer in the relevant employment due to circumstances beyond their control. A recommendation was also made to consider introducing workplace savings schemes similar to the savings schemes applying in the United Kingdom. An education campaign by the South African Revenue Service was recommended, to inform the public of investment incentives. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2024
- Full Text:
An assessment of the status of psylloid species (Hemiptera: Psylloidea) as potential pests of commercial citrus in southern Africa: implications for pest management
- Authors: Moagi, Raynold
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464417 , vital:76509
- Description: Psylloids (Hemiptera: Psylloidea), constitute a group of plant sap-sucking insects, some of which are economically significant pests in different ecosystems due to their potential to transmit Gram-negative bacteria, such as the Candidatus Liberibacter species. The African citrus triozid (ACT), Trioza erytreae (Del Guercio), which transmits African citrus greening and the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, which transmits Asian citrus greening are significant threats to citrus. Asian citrus psyllid poses a global economic threat due to its ability to vector “Candidatus Liberibacter asiaticus” (CLas), which can rapidly kill citrus trees. However, both ACP and CLas are currently not present in southern Africa but are present in East and West Africa. In the Afrotropical region, 71 triozid species are known to occur and approximately 41 described Diaphorina species in southern Africa. Currently, two indigenous Diaphorina species, Diaphorina punctulata and Diaphorina zebrana have been documented to feed on citrus. There is a significant knowledge gap regarding the ecological roles of other indigenous psylloid species occurring within the citrus environments. Therefore, this study aimed to: (i) determine the diversity and community structure of psylloid species in citrus environments, and (ii) their host ranges through DNA analysis of gut contents to determine if they fed on citrus. Field surveys were carried out across 12 distinct commercial citrus environments across Limpopo and Mpumalanga provinces between 2022 and 2023. Psylloids were collected using yellow sticky traps and an insect sweep-net. Collected psylloid specimens were preserved in 70% ethanol vials and identified to the lowest possible taxonomic level (i.e. genus or species) using both published and unpublished dichotomous identification keys. Furthermore, citrus leaf samples were collected from the same plants on which psylloids were found in the orchards. Genomic DNA (gDNA) was extracted from both leaf and psylloid samples using two different DNA extraction methods. To confirm if citrus DNA could be detected in the psylloid guts, all leaf gDNA samples were initially amplified using the rbcLaF/R primer pair, targeting a 530-bp region of the chloroplast rbcL gene through the polymerase chain reaction (PCR). Lastly, gut content analysis was performed on 11 psylloid species using the same primer pair through PCR to detect citrus DNA. A total of 4,900 psylloids belonging to five families (i.e. Aphalaridae, Carsidaridae, Liviidae, Psyllidae and Triozidae), 19 genera and 47 species, were collected in citrus environments. More psylloids were recorded in Limpopo (3,754) than in Mpumalanga (1,146). The most abundant species were Pauropsylla trichaeta (1,680), followed by Diaphorina punctulata (466), Trioza erytreae (426), Diaphorina virgata (371), Euryconus sp. (358), Cacopsylla sp. (311), Retroacizzia mopanei (263), Acizzia russellae-group (240), Acizzia sp.3 (216) and Acizzia sp.2 (140). Yellow sticky traps captured 3,265 psylloids in citrus orchards, while an insect sweep-net collected 1,635 psylloids (477 from citrus orchards and 1,158 from adjacent natural vegetation). Data from the insect sweep-net revealed that 22 psylloid species were recorded on citrus. In comparison, nine psylloid species were found on Vachellia spp. and unidentified plant species separately, whereas six, three and two psylloid species were recorded on marula, Ficus sp. and mopane, respectively. The abundance, richness and community structure of psylloids differed significantly between the collection methods, provinces and among plant species. The rbcLaF/R primer pair amplified all citrus leaf gDNA samples, producing amplicons of the targeted 530-bp size. The PCR analysis of 11 psylloid species showed that the rbcLaF/R primer pair amplified plant DNA, with PCR-amplified plant DNA samples producing amplicons between 500-bp and 750-bp in the gut contents of five psyllid species: Diaphorina punctulata, Diaphorina virgata, Diaphorina zebrana, Euryconus sp. and Trioza erytreae. However, the targeted 530-bp plant DNA region was only amplified from the gut contents of Euryconus sp. and Diaphorina punctulata. This study documented psylloid diversity and community structure within commercial citrus environments. The findings indicate that the community of psylloids was diverse in citrus environments, with yellow sticky traps being more effective in monitoring different psyllid species within these environments. Furthermore, the PCR analysis detected citrus DNA in the gut contents of Euryconus sp. and Diaphorina punctulata, suggesting that they could be nibbling on citrus when their specific or main host-plants adjacent to citrus orchards are depleted. However, these insects do not lay their eggs or complete their life cycle on citrus, further confirming that citrus is not their host-plant. Thus, further studies, including Sanger sequencing of PCR-amplified plant DNA, are recommended to confirm the ingested plant species, and host-specific testing including infection trials needs to be conducted. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Authors: Moagi, Raynold
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464417 , vital:76509
- Description: Psylloids (Hemiptera: Psylloidea), constitute a group of plant sap-sucking insects, some of which are economically significant pests in different ecosystems due to their potential to transmit Gram-negative bacteria, such as the Candidatus Liberibacter species. The African citrus triozid (ACT), Trioza erytreae (Del Guercio), which transmits African citrus greening and the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, which transmits Asian citrus greening are significant threats to citrus. Asian citrus psyllid poses a global economic threat due to its ability to vector “Candidatus Liberibacter asiaticus” (CLas), which can rapidly kill citrus trees. However, both ACP and CLas are currently not present in southern Africa but are present in East and West Africa. In the Afrotropical region, 71 triozid species are known to occur and approximately 41 described Diaphorina species in southern Africa. Currently, two indigenous Diaphorina species, Diaphorina punctulata and Diaphorina zebrana have been documented to feed on citrus. There is a significant knowledge gap regarding the ecological roles of other indigenous psylloid species occurring within the citrus environments. Therefore, this study aimed to: (i) determine the diversity and community structure of psylloid species in citrus environments, and (ii) their host ranges through DNA analysis of gut contents to determine if they fed on citrus. Field surveys were carried out across 12 distinct commercial citrus environments across Limpopo and Mpumalanga provinces between 2022 and 2023. Psylloids were collected using yellow sticky traps and an insect sweep-net. Collected psylloid specimens were preserved in 70% ethanol vials and identified to the lowest possible taxonomic level (i.e. genus or species) using both published and unpublished dichotomous identification keys. Furthermore, citrus leaf samples were collected from the same plants on which psylloids were found in the orchards. Genomic DNA (gDNA) was extracted from both leaf and psylloid samples using two different DNA extraction methods. To confirm if citrus DNA could be detected in the psylloid guts, all leaf gDNA samples were initially amplified using the rbcLaF/R primer pair, targeting a 530-bp region of the chloroplast rbcL gene through the polymerase chain reaction (PCR). Lastly, gut content analysis was performed on 11 psylloid species using the same primer pair through PCR to detect citrus DNA. A total of 4,900 psylloids belonging to five families (i.e. Aphalaridae, Carsidaridae, Liviidae, Psyllidae and Triozidae), 19 genera and 47 species, were collected in citrus environments. More psylloids were recorded in Limpopo (3,754) than in Mpumalanga (1,146). The most abundant species were Pauropsylla trichaeta (1,680), followed by Diaphorina punctulata (466), Trioza erytreae (426), Diaphorina virgata (371), Euryconus sp. (358), Cacopsylla sp. (311), Retroacizzia mopanei (263), Acizzia russellae-group (240), Acizzia sp.3 (216) and Acizzia sp.2 (140). Yellow sticky traps captured 3,265 psylloids in citrus orchards, while an insect sweep-net collected 1,635 psylloids (477 from citrus orchards and 1,158 from adjacent natural vegetation). Data from the insect sweep-net revealed that 22 psylloid species were recorded on citrus. In comparison, nine psylloid species were found on Vachellia spp. and unidentified plant species separately, whereas six, three and two psylloid species were recorded on marula, Ficus sp. and mopane, respectively. The abundance, richness and community structure of psylloids differed significantly between the collection methods, provinces and among plant species. The rbcLaF/R primer pair amplified all citrus leaf gDNA samples, producing amplicons of the targeted 530-bp size. The PCR analysis of 11 psylloid species showed that the rbcLaF/R primer pair amplified plant DNA, with PCR-amplified plant DNA samples producing amplicons between 500-bp and 750-bp in the gut contents of five psyllid species: Diaphorina punctulata, Diaphorina virgata, Diaphorina zebrana, Euryconus sp. and Trioza erytreae. However, the targeted 530-bp plant DNA region was only amplified from the gut contents of Euryconus sp. and Diaphorina punctulata. This study documented psylloid diversity and community structure within commercial citrus environments. The findings indicate that the community of psylloids was diverse in citrus environments, with yellow sticky traps being more effective in monitoring different psyllid species within these environments. Furthermore, the PCR analysis detected citrus DNA in the gut contents of Euryconus sp. and Diaphorina punctulata, suggesting that they could be nibbling on citrus when their specific or main host-plants adjacent to citrus orchards are depleted. However, these insects do not lay their eggs or complete their life cycle on citrus, further confirming that citrus is not their host-plant. Thus, further studies, including Sanger sequencing of PCR-amplified plant DNA, are recommended to confirm the ingested plant species, and host-specific testing including infection trials needs to be conducted. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
An evaluation study of the climate change adaptation plans for a provincial conservation authority in South Africa
- Van den Berg-McGregor, Eleanor Charmell
- Authors: Van den Berg-McGregor, Eleanor Charmell
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461930 , vital:76252
- Description: While there are natural changes in climate over time, the climate change phenomenon of global warming that the Earth is currently experiencing is human-induced. The impact of human-induced climate change has led to unprecedented global warming and has become evident as there have been increases in the frequency and intensity of extreme weather events such as inter alia, heatwaves, droughts and floods. This climate change trajectory poses a risk to the Earth’s ability to continue providing sustainable ecosystem services necessary to sustain life on Earth. Therefore, considering the risks and impacts of climate change, there is a need to strengthen the global response to the threat of climate change, and hence, there is a need for climate change adaptation (CCA). Some benefits of CCA include the reduction of risks to nature and people, biodiversity conservation, food security, livelihoods and human well-being. Through a CCA lens within the biodiversity and conservation sector, underpinned by Resilience Theory, this research study sets out to identify and evaluate the CCA plans of a provincial conservation authority. By reviewing the current literature for CCA, the insights gained allowed for the emergence of key characteristics for good CCA in the biodiversity and conservation sector, and the evaluation of CapeNature’s (a provincial conservation authority situated in the Westen Cape of South Africa) CCA plans against these key characteristics that emerged for CCA and resilience planning in protected areas and ecosystems. Qualitative data was gathered via focus groups and individual semi-structured interviews with seven key knowledge holders of CapeNature’s CCA planning processes, plans and management approaches, and through document analysis of the entity’s CCA plans, whereafter it was evaluated against the key characteristics. Challenges towards CCA and opportunities that can be explored for CCA were identified as well. This research study has revealed that CapeNature does not have a single all-encompassing CCA plan but has various CCA approaches that consider the key characteristics necessary for good CCA. However, the entity faces various challenges regarding its intention to implement these approaches over the long term. Challenges ranged from a fragmented approach to CCA to compromised capacity and capability to implement their CCA plans over time. A recurring challenge was the lack of financial resources, and this, combined with the entity’s current inability to secure sustainable financing, was emphasised as the key factor to be addressed towards facilitating the success of the entity’s CCA plans. It also emerged that CCA approaches are interdependent and linked as in various instances, when one key CCA characteristic was compromised, it had a detrimental effect on other CCA approaches. The study concludes by making recommendations to enhance CapeNature’s CCA and resilience planning, noting that these may be of relevance to other conservation agencies as well. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
- Authors: Van den Berg-McGregor, Eleanor Charmell
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461930 , vital:76252
- Description: While there are natural changes in climate over time, the climate change phenomenon of global warming that the Earth is currently experiencing is human-induced. The impact of human-induced climate change has led to unprecedented global warming and has become evident as there have been increases in the frequency and intensity of extreme weather events such as inter alia, heatwaves, droughts and floods. This climate change trajectory poses a risk to the Earth’s ability to continue providing sustainable ecosystem services necessary to sustain life on Earth. Therefore, considering the risks and impacts of climate change, there is a need to strengthen the global response to the threat of climate change, and hence, there is a need for climate change adaptation (CCA). Some benefits of CCA include the reduction of risks to nature and people, biodiversity conservation, food security, livelihoods and human well-being. Through a CCA lens within the biodiversity and conservation sector, underpinned by Resilience Theory, this research study sets out to identify and evaluate the CCA plans of a provincial conservation authority. By reviewing the current literature for CCA, the insights gained allowed for the emergence of key characteristics for good CCA in the biodiversity and conservation sector, and the evaluation of CapeNature’s (a provincial conservation authority situated in the Westen Cape of South Africa) CCA plans against these key characteristics that emerged for CCA and resilience planning in protected areas and ecosystems. Qualitative data was gathered via focus groups and individual semi-structured interviews with seven key knowledge holders of CapeNature’s CCA planning processes, plans and management approaches, and through document analysis of the entity’s CCA plans, whereafter it was evaluated against the key characteristics. Challenges towards CCA and opportunities that can be explored for CCA were identified as well. This research study has revealed that CapeNature does not have a single all-encompassing CCA plan but has various CCA approaches that consider the key characteristics necessary for good CCA. However, the entity faces various challenges regarding its intention to implement these approaches over the long term. Challenges ranged from a fragmented approach to CCA to compromised capacity and capability to implement their CCA plans over time. A recurring challenge was the lack of financial resources, and this, combined with the entity’s current inability to secure sustainable financing, was emphasised as the key factor to be addressed towards facilitating the success of the entity’s CCA plans. It also emerged that CCA approaches are interdependent and linked as in various instances, when one key CCA characteristic was compromised, it had a detrimental effect on other CCA approaches. The study concludes by making recommendations to enhance CapeNature’s CCA and resilience planning, noting that these may be of relevance to other conservation agencies as well. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
An exploratory study of the benefits of reading clubs for learners in English First Additional Language classrooms
- Authors: Mbebe, Xolela Desmond
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463724 , vital:76435
- Description: The study explored how reading clubs inculcate the love of reading in Komani, Eastern Cape Province, South Africa. Reports indicate that learners at secondary schools do not understand the vocabulary used in comprehension passages. They need exposure to a variety of texts to promote reading comprehension. This study is situated in the interpretive paradigm. The participants were three educators with 24 learners in the reading clubs. Vygotsky’s Socio-Cultural Theory was the theoretical framework to explore how reading clubs promote the love of reading. Data was analysed by using an inductive, thematic approach. The findings indicate that the reading clubs instilled the love of reading among the learners, improving their comprehension skills. The other benefits were that reading clubs are a source of pleasure, instil the culture of reading, and develop the learners’ confidence. The implications of the findings of the study are that reading boosted thinking, reading skills, fluency, knowledge, writing, and vocabulary use. Reading clubs were beneficial to both teachers and learners. Teachers improved their practice and could determine, through oral and written reviews, whether reading took place during the silent reading sessions. Involvement in reading clubs had social benefits for learners. , Thesis (MEd) -- Faculty of Education, Institute for the Study of Englishes of Africa, 2024
- Full Text:
- Authors: Mbebe, Xolela Desmond
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463724 , vital:76435
- Description: The study explored how reading clubs inculcate the love of reading in Komani, Eastern Cape Province, South Africa. Reports indicate that learners at secondary schools do not understand the vocabulary used in comprehension passages. They need exposure to a variety of texts to promote reading comprehension. This study is situated in the interpretive paradigm. The participants were three educators with 24 learners in the reading clubs. Vygotsky’s Socio-Cultural Theory was the theoretical framework to explore how reading clubs promote the love of reading. Data was analysed by using an inductive, thematic approach. The findings indicate that the reading clubs instilled the love of reading among the learners, improving their comprehension skills. The other benefits were that reading clubs are a source of pleasure, instil the culture of reading, and develop the learners’ confidence. The implications of the findings of the study are that reading boosted thinking, reading skills, fluency, knowledge, writing, and vocabulary use. Reading clubs were beneficial to both teachers and learners. Teachers improved their practice and could determine, through oral and written reviews, whether reading took place during the silent reading sessions. Involvement in reading clubs had social benefits for learners. , Thesis (MEd) -- Faculty of Education, Institute for the Study of Englishes of Africa, 2024
- Full Text:
An investigation into the causes and effect of rising public debt in South Africa, 2009-2019
- Authors: Mzumala, Mirriam
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461918 , vital:76251
- Description: This study delves into the intricate factors contributing to the rising public debt in South Africa between 2009 and 2019, while also scrutinising the efficacy of public debt expenditure during this period. By examining data sourced from the SA National Treasury of South Africa and the South African Reserve Bank (SARB), the research endeavours to elucidate the underlying causes behind the burgeoning public debt and assess the impact of expenditure patterns on economic outcomes. The global financial crisis of 2008/2009 marked a pivotal juncture for South Africa's economy, precipitating a series of fiscal challenges that reverberated throughout the subsequent decade. Against this backdrop, this study embarks on a dual mission: firstly, to decipher the drivers underpinning the surge in public debt, and secondly, to gauge the efficacy of public expenditure vis-à-vis economic growth and development objectives. From 2009 to 2019, fiscal analysis shows a clear pattern of growing budget deficits, with government spending surpassing revenue growth. South Africa's fiscal policy has heavily favoured deficit spending, relying on debt to cover revenue shortfalls and maintain expenditure growth. Most government spending goes towards current payments and social transfers, leaving little for capital formation. Despite the National Development Plan's emphasis on investing in productive assets, both public and private sector investments have consistently fallen below targets, hindering significant contributions to economic growth. The rising public debt in South Africa stems from numerous factors, including excessive spending on unproductive areas like government compensation and social transfers, alongside high borrowing costs. This consumption-focused economic approach, coupled with insufficient investment in productive assets, has hindered South Africa's economic progress compared to global counterparts. Given these challenges, it is crucial to shift fiscal priorities towards strategies focused on investment-led growth. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
- Authors: Mzumala, Mirriam
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461918 , vital:76251
- Description: This study delves into the intricate factors contributing to the rising public debt in South Africa between 2009 and 2019, while also scrutinising the efficacy of public debt expenditure during this period. By examining data sourced from the SA National Treasury of South Africa and the South African Reserve Bank (SARB), the research endeavours to elucidate the underlying causes behind the burgeoning public debt and assess the impact of expenditure patterns on economic outcomes. The global financial crisis of 2008/2009 marked a pivotal juncture for South Africa's economy, precipitating a series of fiscal challenges that reverberated throughout the subsequent decade. Against this backdrop, this study embarks on a dual mission: firstly, to decipher the drivers underpinning the surge in public debt, and secondly, to gauge the efficacy of public expenditure vis-à-vis economic growth and development objectives. From 2009 to 2019, fiscal analysis shows a clear pattern of growing budget deficits, with government spending surpassing revenue growth. South Africa's fiscal policy has heavily favoured deficit spending, relying on debt to cover revenue shortfalls and maintain expenditure growth. Most government spending goes towards current payments and social transfers, leaving little for capital formation. Despite the National Development Plan's emphasis on investing in productive assets, both public and private sector investments have consistently fallen below targets, hindering significant contributions to economic growth. The rising public debt in South Africa stems from numerous factors, including excessive spending on unproductive areas like government compensation and social transfers, alongside high borrowing costs. This consumption-focused economic approach, coupled with insufficient investment in productive assets, has hindered South Africa's economic progress compared to global counterparts. Given these challenges, it is crucial to shift fiscal priorities towards strategies focused on investment-led growth. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
- Full Text:
An investigation into the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of Tulbaghia violacea collected from the Eastern Cape and Gauteng Province
- Authors: Kader, Tasmeera
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461819 , vital:76242
- Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
- Authors: Kader, Tasmeera
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/461819 , vital:76242
- Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
- Full Text:
Aspects of the sustainability of the wild honeybush industry
- Authors: McGregor, Gillian Kathleen
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464266 , vital:76493 , DOI 10.21504/10962/464266
- Description: Honeybush products are uniquely South African, derived from plants of the fynbos genus, Cyclopia. Cyclopia intermedia is the most widespread species, distributed across 11 496 km2 of the Cape Fold Mountains, and provided the bulk of supply for the industry until 2022. While the industry is small, it is a locally significant industry affecting the livelihoods of harvesters, farmers and processors in the greater Langkloof region of the Eastern and Western Cape provinces of South Africa. The industry has evolved from a cottage one, to a commercial scale, and concerns have been raised over the sustainability of the wild resource specifically, and the industry in general. The research aimed to improve our understanding of aspects of the sustainability of the wild honeybush industry. A mixed methods design was adopted, which allowed for the inclusion of data collection approaches and analysis which tell a richer story than one with a singular modus. Four objectives were identified, which entailed: (i) mapping the resource to establish the distribution range of C. intermedia; (ii) recording of local ecological knowledge (LEK) and traditional ecological knowledge (TEK) around best practice harvesting; (iii) assessing the sustainability of harvest enterprise types through analysis of yield history and harvester loads; (iv) identifying differences between harvested and unharvested C. intermedia populations. Mapping of the resource drew on a variety of existing data sources, field mapping, GIS-based analysis, species distribution modelling and expert mapping to create a comprehensive and accurate map of the species distribution. The species is estimated to occupy a distribution range of 11 496 km2, 49% of which occurs in formally protected areas. Based on local scale mapping by experts, 100km2 is estimated to be in use for wild harvesting in the production area of the Langkloof. Information on best practice harvesting was collected through in-depth interviews with harvesters, harvest managers, processors and farmers (in the field at harvest events) and through questionnaire surveys and focus group discussions at a honeybush stakeholder workshop. In combination with harvest event surveys at which harvester practice was observed and recorded, and surveys were conducted of the harvest yield and of plants in the harvested population, the information was used to produce the first formal account of best practice for sustainable harvesting of wild honeybush. To assess the sustainability of harvest enterprises and associated harvester livelihoods, harvester managers were interviewed to create profiles of typical harvesting enterprises based on their practices and harvest yield histories. Of the three harvest enterprises considered, two showed sustained yields over time, while those of a large contract type enterprise were less sustainable with declining yields on three out of six farms. From a statistical analysis of the records it was found that the most effective team size was 10 or less harvesters in terms of livelihood sustainability. They could earn a fair livelihood (ZAR67 680.00) per annum, based on a 94 kg load per daily harvest event, sold to the processor at ZAR 5.00, for nine months of the year, working a four-day week. For a team to operate sustainably, it was found that it should consist of experienced harvesters harvesting conservatively, at intervals of at least four years, and be responsive to local environmental conditions. Detailed field surveys of C. intermedia plants at 38 sites representing harvested and unharvested populations were carried out to understand the impact of harvesting on the plants. A statistical analysis of the plant's dimensions related to the physical environment, fire and harvest history using generalised linear models revealed that while unharvested plants were slightly larger, only crown diameter and stem counts were significantly so. Seedlings were noticeably scarce at all sites, including recently burnt sites. A significant finding of the research was that in a fecundity survey, unharvested plants produced significantly more pods. The impact of this is unknown, but it has implications for management and the sustainable use of wild resources in the long term. Further understanding of the impact of harvesting came from surveys of cultivated stands of C. intermedia (different ages and harvest histories, but all harvested at three-year intervals) and surveys of a wild population, which was subjected to unregulated harvesting. For the cultivated stand: after 12 years, plants declined in all measured dimensions, while in the wild population, 45% of the plants died over a seven-year period. The surveys proved that a three-year interval or frequent, unregulated harvest is unsustainable. The research was used to produce the wild harvesting guidelines, which have become the accepted standard for the industry. It has demonstrated that under the right circumstances, harvesting of the wild C. intermedia resource is broadly sustainable. However, there needs to be informed management of the use of the resource in terms of harvest team types and their protocols, particularly with regard to harvest intervals and possible interventions to improve seed production to achieve sustainable use of the resource in social, economic and ecological terms. , Thesis (PhD) -- Faculty of Science, Geography, 2024
- Full Text:
- Authors: McGregor, Gillian Kathleen
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464266 , vital:76493 , DOI 10.21504/10962/464266
- Description: Honeybush products are uniquely South African, derived from plants of the fynbos genus, Cyclopia. Cyclopia intermedia is the most widespread species, distributed across 11 496 km2 of the Cape Fold Mountains, and provided the bulk of supply for the industry until 2022. While the industry is small, it is a locally significant industry affecting the livelihoods of harvesters, farmers and processors in the greater Langkloof region of the Eastern and Western Cape provinces of South Africa. The industry has evolved from a cottage one, to a commercial scale, and concerns have been raised over the sustainability of the wild resource specifically, and the industry in general. The research aimed to improve our understanding of aspects of the sustainability of the wild honeybush industry. A mixed methods design was adopted, which allowed for the inclusion of data collection approaches and analysis which tell a richer story than one with a singular modus. Four objectives were identified, which entailed: (i) mapping the resource to establish the distribution range of C. intermedia; (ii) recording of local ecological knowledge (LEK) and traditional ecological knowledge (TEK) around best practice harvesting; (iii) assessing the sustainability of harvest enterprise types through analysis of yield history and harvester loads; (iv) identifying differences between harvested and unharvested C. intermedia populations. Mapping of the resource drew on a variety of existing data sources, field mapping, GIS-based analysis, species distribution modelling and expert mapping to create a comprehensive and accurate map of the species distribution. The species is estimated to occupy a distribution range of 11 496 km2, 49% of which occurs in formally protected areas. Based on local scale mapping by experts, 100km2 is estimated to be in use for wild harvesting in the production area of the Langkloof. Information on best practice harvesting was collected through in-depth interviews with harvesters, harvest managers, processors and farmers (in the field at harvest events) and through questionnaire surveys and focus group discussions at a honeybush stakeholder workshop. In combination with harvest event surveys at which harvester practice was observed and recorded, and surveys were conducted of the harvest yield and of plants in the harvested population, the information was used to produce the first formal account of best practice for sustainable harvesting of wild honeybush. To assess the sustainability of harvest enterprises and associated harvester livelihoods, harvester managers were interviewed to create profiles of typical harvesting enterprises based on their practices and harvest yield histories. Of the three harvest enterprises considered, two showed sustained yields over time, while those of a large contract type enterprise were less sustainable with declining yields on three out of six farms. From a statistical analysis of the records it was found that the most effective team size was 10 or less harvesters in terms of livelihood sustainability. They could earn a fair livelihood (ZAR67 680.00) per annum, based on a 94 kg load per daily harvest event, sold to the processor at ZAR 5.00, for nine months of the year, working a four-day week. For a team to operate sustainably, it was found that it should consist of experienced harvesters harvesting conservatively, at intervals of at least four years, and be responsive to local environmental conditions. Detailed field surveys of C. intermedia plants at 38 sites representing harvested and unharvested populations were carried out to understand the impact of harvesting on the plants. A statistical analysis of the plant's dimensions related to the physical environment, fire and harvest history using generalised linear models revealed that while unharvested plants were slightly larger, only crown diameter and stem counts were significantly so. Seedlings were noticeably scarce at all sites, including recently burnt sites. A significant finding of the research was that in a fecundity survey, unharvested plants produced significantly more pods. The impact of this is unknown, but it has implications for management and the sustainable use of wild resources in the long term. Further understanding of the impact of harvesting came from surveys of cultivated stands of C. intermedia (different ages and harvest histories, but all harvested at three-year intervals) and surveys of a wild population, which was subjected to unregulated harvesting. For the cultivated stand: after 12 years, plants declined in all measured dimensions, while in the wild population, 45% of the plants died over a seven-year period. The surveys proved that a three-year interval or frequent, unregulated harvest is unsustainable. The research was used to produce the wild harvesting guidelines, which have become the accepted standard for the industry. It has demonstrated that under the right circumstances, harvesting of the wild C. intermedia resource is broadly sustainable. However, there needs to be informed management of the use of the resource in terms of harvest team types and their protocols, particularly with regard to harvest intervals and possible interventions to improve seed production to achieve sustainable use of the resource in social, economic and ecological terms. , Thesis (PhD) -- Faculty of Science, Geography, 2024
- Full Text:
Bio-vectoring by honeybees and symbiosis: a combined approach to controlling Botrytis mould on strawberry
- Authors: Starbuck, Megan
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463985 , vital:76463
- Description: Access restricted. Exxpected release in 2026. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
- Full Text:
- Authors: Starbuck, Megan
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463985 , vital:76463
- Description: Access restricted. Exxpected release in 2026. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
- Full Text:
Burgernomics: Raw BMI vs Adjusted BMI. A comparative analysis of appropriate exchange rate valuation measures
- Gumedze, Siyanda Nakiwe Nomfundo
- Authors: Gumedze, Siyanda Nakiwe Nomfundo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/462702 , vital:76327
- Description: The Big Mac Index was developed in 1986 by The Economist magazine as a playful take on the Purchasing Power Parity theory. Its purpose is to indicate whether a currency is overpriced or undervalued in relation to the real exchange rate and whether it can be used as a reliable indicator of exchange rate predictions. There are two versions of the Big Mac Index: the raw Big Mac Index and the adjusted Big Mac Index. If appropriate, this index might be developed into an economic theory that can be applied to corporate finance, international trade, and international finance. To determine which Big Mac Index measure is a better indicator of exchange rate valuation, a comparison analysis was conducted. This study set out to determine how well the adjusted Big Mac Index performed as a gauge for exchange rate valuation. The research then compares the two Big Mac Index measures' ability to anticipate future exchange rates in order to determine which is more accurate. Data from the South African Reserve Bank and The Economist databases covering 37 nations from 2000 to 2022 were used for the analysis. Exchange rate misalignment trends were assessed globally, and the results indicated that the adjusted BMI was a more accurate measure of purchasing power. Tests of correlation revealed that there was a positive association between the real exchange rate and the Big Mac Index. Findings from a panel ARDL Model indicated that taking into consideration country-specific GDP variations and group heterogeneity can enhance the real exchange rates' ability to predict the raw BMI. The research also focused on the South African Rand to ascertain whether the Big Mac Index validates the Purchasing Power Parity theoretical framework. Using cointegration tests and graphic analysis, it was possible to find evidence for a cointegrating relationship between the real exchange rate and the Big Mac Index measures during the last 20 years. Additionally, a positive correlation between the modified Big Mac Index and terms of trade was discovered in the results, confirming the hypothesis that the Big Mac Index satisfies current account assumptions. Finally, a VEC model demonstrated that the modified BMI outperforms the raw BMI in terms of forecasting estimates. Overall, the study found that the Big Mac Index is more than a bit of fun as per its origin. The results showed that the adjusted Big Mac Index has practical applications and the potential to be considered as an economic theory. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
- Authors: Gumedze, Siyanda Nakiwe Nomfundo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/462702 , vital:76327
- Description: The Big Mac Index was developed in 1986 by The Economist magazine as a playful take on the Purchasing Power Parity theory. Its purpose is to indicate whether a currency is overpriced or undervalued in relation to the real exchange rate and whether it can be used as a reliable indicator of exchange rate predictions. There are two versions of the Big Mac Index: the raw Big Mac Index and the adjusted Big Mac Index. If appropriate, this index might be developed into an economic theory that can be applied to corporate finance, international trade, and international finance. To determine which Big Mac Index measure is a better indicator of exchange rate valuation, a comparison analysis was conducted. This study set out to determine how well the adjusted Big Mac Index performed as a gauge for exchange rate valuation. The research then compares the two Big Mac Index measures' ability to anticipate future exchange rates in order to determine which is more accurate. Data from the South African Reserve Bank and The Economist databases covering 37 nations from 2000 to 2022 were used for the analysis. Exchange rate misalignment trends were assessed globally, and the results indicated that the adjusted BMI was a more accurate measure of purchasing power. Tests of correlation revealed that there was a positive association between the real exchange rate and the Big Mac Index. Findings from a panel ARDL Model indicated that taking into consideration country-specific GDP variations and group heterogeneity can enhance the real exchange rates' ability to predict the raw BMI. The research also focused on the South African Rand to ascertain whether the Big Mac Index validates the Purchasing Power Parity theoretical framework. Using cointegration tests and graphic analysis, it was possible to find evidence for a cointegrating relationship between the real exchange rate and the Big Mac Index measures during the last 20 years. Additionally, a positive correlation between the modified Big Mac Index and terms of trade was discovered in the results, confirming the hypothesis that the Big Mac Index satisfies current account assumptions. Finally, a VEC model demonstrated that the modified BMI outperforms the raw BMI in terms of forecasting estimates. Overall, the study found that the Big Mac Index is more than a bit of fun as per its origin. The results showed that the adjusted Big Mac Index has practical applications and the potential to be considered as an economic theory. , Thesis (MCom) -- Faculty of Commerce, Economics and Economic History, 2024
- Full Text:
Carbonylation of cyclohexene with carbon dioxide (CO2) using transition metals as heterogeneous and homogeneous catalysts
- Authors: Sekaleli, Bafokeng Thabelo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464565 , vital:76522
- Description: From a green chemistry perspective, carbon dioxide (CO2) emerges as an appealing C1 synthon, given its abundance in the atmosphere and cost-effectiveness. Many essential chemicals for daily life are derived from fossilized carbon sources like coal, petroleum, and natural gas. However, the by-product of these processes, CO2, poses environmental risks when excessively emitted as a greenhouse gas. Achieving a balance between carbon emissions and removal is crucial to address environmental concerns surrounding CO2. Utilizing CO2 as a C1 source in organic synthesis holds promise for mitigating this balance in the long term. Combining CO2 with other underutilized fine chemicals, such as alkanes, alkenes, and alkynes, to produce more valuable platform chemicals presents an economically viable strategy due to carbon dioxide’s abundance, low cost, and recyclability. Despite its simplicity, CO2's high thermodynamic stability and low kinetic reactivity, owing to its highly oxidized state, pose challenges to its use as a feedstock. Overcoming these hurdles requires catalysts to enhance CO2 reactivity. Our work focuses on developing and employing catalytic systems capable of activating CO2 as a C1 synthon in reactions with cyclohexene and a reducing agent to yield carboxylic acids or esters. In one approach, we have developed heterogeneous catalyst systems comprising transition metals (Au, Fe, Ni, Ru) supported on metal oxide (TiO2). Characterization techniques such as TEM, EDX, UV-Vis, BET, and XRD were used to study the properties of these materials. The catalysts were evaluated in a reaction involving cyclohexene, CO2, and H2O. In another approach, we explored the use of cyclo-tris(tetracarbonylruthenium) [Ru3(CO)12] as a homogeneous catalyst in a reaction involving cyclohexene, methanol, and CO2 in the presence of an ionic liquid, 1-Butyl-3-methylimidazolium chloride ([BMIM]+Cl-). 1H NMR and ATR-FT-IR were utilized to characterize [BMIM]+Cl-. The reaction product was characterised utilizing GC-MS. Upon seeing that Ru3(CO)12 changes color from orange to black when exposed to heat, an investigation was undertaken on the kind of transformations that the catalyst undergoes. This investigation was carried out with the hopes of finding the structures that could be resulting from Ru3(CO)12 during the reaction and their significance to it. The orange and black Ru complexes were characterized utilizing DSC, TGA, ATR-FT-IR and PXRD. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Authors: Sekaleli, Bafokeng Thabelo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464565 , vital:76522
- Description: From a green chemistry perspective, carbon dioxide (CO2) emerges as an appealing C1 synthon, given its abundance in the atmosphere and cost-effectiveness. Many essential chemicals for daily life are derived from fossilized carbon sources like coal, petroleum, and natural gas. However, the by-product of these processes, CO2, poses environmental risks when excessively emitted as a greenhouse gas. Achieving a balance between carbon emissions and removal is crucial to address environmental concerns surrounding CO2. Utilizing CO2 as a C1 source in organic synthesis holds promise for mitigating this balance in the long term. Combining CO2 with other underutilized fine chemicals, such as alkanes, alkenes, and alkynes, to produce more valuable platform chemicals presents an economically viable strategy due to carbon dioxide’s abundance, low cost, and recyclability. Despite its simplicity, CO2's high thermodynamic stability and low kinetic reactivity, owing to its highly oxidized state, pose challenges to its use as a feedstock. Overcoming these hurdles requires catalysts to enhance CO2 reactivity. Our work focuses on developing and employing catalytic systems capable of activating CO2 as a C1 synthon in reactions with cyclohexene and a reducing agent to yield carboxylic acids or esters. In one approach, we have developed heterogeneous catalyst systems comprising transition metals (Au, Fe, Ni, Ru) supported on metal oxide (TiO2). Characterization techniques such as TEM, EDX, UV-Vis, BET, and XRD were used to study the properties of these materials. The catalysts were evaluated in a reaction involving cyclohexene, CO2, and H2O. In another approach, we explored the use of cyclo-tris(tetracarbonylruthenium) [Ru3(CO)12] as a homogeneous catalyst in a reaction involving cyclohexene, methanol, and CO2 in the presence of an ionic liquid, 1-Butyl-3-methylimidazolium chloride ([BMIM]+Cl-). 1H NMR and ATR-FT-IR were utilized to characterize [BMIM]+Cl-. The reaction product was characterised utilizing GC-MS. Upon seeing that Ru3(CO)12 changes color from orange to black when exposed to heat, an investigation was undertaken on the kind of transformations that the catalyst undergoes. This investigation was carried out with the hopes of finding the structures that could be resulting from Ru3(CO)12 during the reaction and their significance to it. The orange and black Ru complexes were characterized utilizing DSC, TGA, ATR-FT-IR and PXRD. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
Carnivory submerged: aspects of the ecology and ecophysiology of the aquatic Utricularia stellaris L. fil. (Lentibulariaceae) in South Africa
- Authors: Marais, Alice-Jane
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464473 , vital:76514
- Description: The trapping structures produced by aquatic species of Utricularia have traditionally been interpreted to function as adaptations to capture and break down zooplankton prey, as in other carnivorous plants, to overcome nutrient limitations. However, an increasing number of studies have found that these plants may also rely on benefits derived from living mutualistic microbial communities contained within traps. This study documents aspects of the environmental, growth and physiological characteristics of U. stellaris to inform and to form a basis for future investigation into the plant-microbe interaction. The environmental conditions in which U. stellaris grows were documented to identify potential adverse conditions plants are subject to in situ, from which nutrient limitation was identified as a primary limitation. Plant growth and trapping structures were then assessed to identify possible adaptations of plants to overcome these limitations. The production of trapping structures likely constitutes an adaptive trait, with 30% of total biomass per node allocated to the production of these structures. Based on their capture function, traps may aid plants based on their contents, possibly supplementing plants with nutrients. Although assessments of the habitats of U. stellaris indicate that dissolved CO₂ concentrations in the ambient water are high, CO₂ may still be limiting to the photosynthetic rates of these plants due to viscous water resisting the diffusion of CO₂. The primary site of photosynthesis in U. stellaris is leaves and trap tissue’s contribution to photosynthetic output is negligible. U. stellaris plants are subject to CO₂ limitations in natural pond conditions, making the substantial allocation of resources to non-photosynthetic trapping tissue even more costly. Therefore, benefits gained from trapping structures are likely to be derived from trap contents; having ruled out the possibility that the trap tissue itself is photosynthetic. Trap contents of U. stellaris were assessed. The proportion of traps containing living microbial communities greatly exceeded the proportion containing zooplankton prey. In addition, these communities were found to be diverse, stable, and self-sustaining. These results suggest that trapping structures may be beneficial for both the carnivorous capture of prey and the housing of living microbial communities. These results indicate the plantmicrobe interaction in U. stellaris warrants further study. , Thesis (MSc) -- Faculty of Science, Botany, 2024
- Full Text:
- Authors: Marais, Alice-Jane
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464473 , vital:76514
- Description: The trapping structures produced by aquatic species of Utricularia have traditionally been interpreted to function as adaptations to capture and break down zooplankton prey, as in other carnivorous plants, to overcome nutrient limitations. However, an increasing number of studies have found that these plants may also rely on benefits derived from living mutualistic microbial communities contained within traps. This study documents aspects of the environmental, growth and physiological characteristics of U. stellaris to inform and to form a basis for future investigation into the plant-microbe interaction. The environmental conditions in which U. stellaris grows were documented to identify potential adverse conditions plants are subject to in situ, from which nutrient limitation was identified as a primary limitation. Plant growth and trapping structures were then assessed to identify possible adaptations of plants to overcome these limitations. The production of trapping structures likely constitutes an adaptive trait, with 30% of total biomass per node allocated to the production of these structures. Based on their capture function, traps may aid plants based on their contents, possibly supplementing plants with nutrients. Although assessments of the habitats of U. stellaris indicate that dissolved CO₂ concentrations in the ambient water are high, CO₂ may still be limiting to the photosynthetic rates of these plants due to viscous water resisting the diffusion of CO₂. The primary site of photosynthesis in U. stellaris is leaves and trap tissue’s contribution to photosynthetic output is negligible. U. stellaris plants are subject to CO₂ limitations in natural pond conditions, making the substantial allocation of resources to non-photosynthetic trapping tissue even more costly. Therefore, benefits gained from trapping structures are likely to be derived from trap contents; having ruled out the possibility that the trap tissue itself is photosynthetic. Trap contents of U. stellaris were assessed. The proportion of traps containing living microbial communities greatly exceeded the proportion containing zooplankton prey. In addition, these communities were found to be diverse, stable, and self-sustaining. These results suggest that trapping structures may be beneficial for both the carnivorous capture of prey and the housing of living microbial communities. These results indicate the plantmicrobe interaction in U. stellaris warrants further study. , Thesis (MSc) -- Faculty of Science, Botany, 2024
- Full Text:
Co-crystal formation of pharmaceutical and veterinary tranquilizer molecules
- Mngwengwe, Bongeka Naledi Precious
- Authors: Mngwengwe, Bongeka Naledi Precious
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464532 , vital:76519
- Description: Midazolam, a 1,4-benzodiazepine derivative is commonly used to treat anxiety, insomnia and may be used as a sedative in anaesthesia as it has calming, anti-convulsant and muscle relaxant properties. Midazolam has a rapid onset but a short duration of action resulting in fewer adverse effects. Midazolam also has the potential to form insoluble crystalline precipitates in pharmaceutical dosage forms such as syrups and solutions, which is a challenge in formulation and process development activities. The primary goal of this research was to prepare multicomponent crystals of midazolam free base, specifically targeting interactions with coformers structurally similar to methyl paraben. Key preparation techniques included neat grinding, liquid-assisted grinding, and slow evaporation. The resulting solid forms were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and powder X-Ray Diffraction (PXRD). In addition, Single-Crystal X-Ray Diffraction (SCXRD) was used to elucidate detailed structural information on the novel multicomponent crystals formed. Successful preparation of midazolam free base from the hydrochloride salt was confirmed through FTIR, DSC, and PXRD analysis. Different co-crystals and salts of midazolam with coformers such as salicylic acid (SA), benzoic acid (BA), 3-hydroxybenzoic acid (3-HBA) and p-aminobenzoic acid (PABA) were synthesized and characterized. The structure of the single crystal obtained from a veterinary tranquilizer solution was solved and found to be a salt that had formed between midazolam free base, midazolam HCl, and methyl paraben. This finding inspired further investigation of similar multicomponent crystals of midazolam and methyl paraben analogues. This study demonstrated the effectiveness of both mechanochemical and slow evaporation methods for the preparation of multicomponent crystals. PXRD and DSC provided insights into the stability and purity of the crystals that had formed and the differences in melting points and PXRD patterns were particularly important in this regard. Differences in FTIR spectra were used to distinguish between different solid forms and to confirm the successful formation of new solid forms. Extensive searches in the Cambridge Structural Database (CSD) confirmed that the multicomponent crystals of midazolam, such as MDZ‧SA, MDZ‧BA, MDZ‧3-HBA, and MDZ‧PABA, had not previously been reported, highlighting the novelty of these findings. The research successfully isolated and characterized several novel multicomponent crystals of midazolam, demonstrating the potential of mechanochemistry and solvent evaporation techniques in the development of pharmaceutical and veterinary medicinal applications. These findings contribute to the understanding of cocrystal formation and provide a foundation for future studies in which the stability and efficacy of midazolam-based formulations can be evaluated. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Authors: Mngwengwe, Bongeka Naledi Precious
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464532 , vital:76519
- Description: Midazolam, a 1,4-benzodiazepine derivative is commonly used to treat anxiety, insomnia and may be used as a sedative in anaesthesia as it has calming, anti-convulsant and muscle relaxant properties. Midazolam has a rapid onset but a short duration of action resulting in fewer adverse effects. Midazolam also has the potential to form insoluble crystalline precipitates in pharmaceutical dosage forms such as syrups and solutions, which is a challenge in formulation and process development activities. The primary goal of this research was to prepare multicomponent crystals of midazolam free base, specifically targeting interactions with coformers structurally similar to methyl paraben. Key preparation techniques included neat grinding, liquid-assisted grinding, and slow evaporation. The resulting solid forms were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and powder X-Ray Diffraction (PXRD). In addition, Single-Crystal X-Ray Diffraction (SCXRD) was used to elucidate detailed structural information on the novel multicomponent crystals formed. Successful preparation of midazolam free base from the hydrochloride salt was confirmed through FTIR, DSC, and PXRD analysis. Different co-crystals and salts of midazolam with coformers such as salicylic acid (SA), benzoic acid (BA), 3-hydroxybenzoic acid (3-HBA) and p-aminobenzoic acid (PABA) were synthesized and characterized. The structure of the single crystal obtained from a veterinary tranquilizer solution was solved and found to be a salt that had formed between midazolam free base, midazolam HCl, and methyl paraben. This finding inspired further investigation of similar multicomponent crystals of midazolam and methyl paraben analogues. This study demonstrated the effectiveness of both mechanochemical and slow evaporation methods for the preparation of multicomponent crystals. PXRD and DSC provided insights into the stability and purity of the crystals that had formed and the differences in melting points and PXRD patterns were particularly important in this regard. Differences in FTIR spectra were used to distinguish between different solid forms and to confirm the successful formation of new solid forms. Extensive searches in the Cambridge Structural Database (CSD) confirmed that the multicomponent crystals of midazolam, such as MDZ‧SA, MDZ‧BA, MDZ‧3-HBA, and MDZ‧PABA, had not previously been reported, highlighting the novelty of these findings. The research successfully isolated and characterized several novel multicomponent crystals of midazolam, demonstrating the potential of mechanochemistry and solvent evaporation techniques in the development of pharmaceutical and veterinary medicinal applications. These findings contribute to the understanding of cocrystal formation and provide a foundation for future studies in which the stability and efficacy of midazolam-based formulations can be evaluated. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
Cocrystals, salts and eutectics of anti-tuberculosis medicines
- Authors: Matlapeng, Tsebang Alice
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464521 , vital:76518
- Description: Tuberculosis remains as a prominent cause of death worldwide. This infectious disease is treated with first and second line drugs. However, challenges of multi drug resistant tuberculosis and adverse side effects such as depletion of essential B group vitamins in the body by first line drugs, as well as poor physicochemical properties of second line drugs persist. Cocrystallisation of anti-tubercular drugs with various coformers has therefore been used as an alternative method to improve the physicochemical properties of active pharmaceutical ingredients (API) while maintaining their efficacy. The main objective of this study was to carry out cocrystal screening of anti-tubercular API and vitamin B coformers to make drug-drug or drug-vitamin multicomponent complexes. Preparation of the multicomponent complexes was carried out by mechanochemical grinding (neat grinding (NG), liquid assisted grinding (LAG) and slow evaporation. All complexes were characterised using Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and crystal structures were elucidated using single-crystal X-ray diffraction (SCXRD). The cocrystal screening resulted in the formation of various solid forms, which included cocrystals, salts and eutectic products. Two cocrystals of 4-aminosalicylic acid (PAS) were isolated and characterised. The cocrystal of PAS with isoniazid (INH) demonstrated similar characteristics for both the bulk crystalline material and milled materials. The cocrystal of PAS and pyrazinamide (PYR) prepared using mechanochemical synthesis was met with challenges, while difficulties were also encountered in obtaining suitable crystals for SCXRD analysis. The ground and recrystallised samples of the PAS and pyrazinecarboxylic acid (PCBA) showed distinct differences in their thermal behaviour, with SCXRD revealing the decomposition product phenolammonium-pyrazinecarboxylate salt ‘sans’ the CO2 moiety. Salt formation involving pyridoxine (PN) yielded a salt hydrate with PAS (PN-PAS) and an anhydrous salt with PCBA (PN-PCBA). Both salts exhibited very complex packing arrangements with equally complex thermal behaviour depending on the solvent used during preparation, and the method of preparation. Three eutectic systems involving INH with PYR, PN and pyridoxine hydrochloride (PNꞏHCl) were identified, and their phase diagrams were constructed from DSC data. The eutectic compositions obtained were 1:1 for INH:PYR, 1:1 for INH:PN and 6:4 for INH:PNꞏHCl. Finally, a total of eight multicomponent complexes were prepared using selected API and vitamin B6 components. The results presented here provide motivation for further investigation and evaluation of the pharmacochemical properties of these API. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
- Authors: Matlapeng, Tsebang Alice
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464521 , vital:76518
- Description: Tuberculosis remains as a prominent cause of death worldwide. This infectious disease is treated with first and second line drugs. However, challenges of multi drug resistant tuberculosis and adverse side effects such as depletion of essential B group vitamins in the body by first line drugs, as well as poor physicochemical properties of second line drugs persist. Cocrystallisation of anti-tubercular drugs with various coformers has therefore been used as an alternative method to improve the physicochemical properties of active pharmaceutical ingredients (API) while maintaining their efficacy. The main objective of this study was to carry out cocrystal screening of anti-tubercular API and vitamin B coformers to make drug-drug or drug-vitamin multicomponent complexes. Preparation of the multicomponent complexes was carried out by mechanochemical grinding (neat grinding (NG), liquid assisted grinding (LAG) and slow evaporation. All complexes were characterised using Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and crystal structures were elucidated using single-crystal X-ray diffraction (SCXRD). The cocrystal screening resulted in the formation of various solid forms, which included cocrystals, salts and eutectic products. Two cocrystals of 4-aminosalicylic acid (PAS) were isolated and characterised. The cocrystal of PAS with isoniazid (INH) demonstrated similar characteristics for both the bulk crystalline material and milled materials. The cocrystal of PAS and pyrazinamide (PYR) prepared using mechanochemical synthesis was met with challenges, while difficulties were also encountered in obtaining suitable crystals for SCXRD analysis. The ground and recrystallised samples of the PAS and pyrazinecarboxylic acid (PCBA) showed distinct differences in their thermal behaviour, with SCXRD revealing the decomposition product phenolammonium-pyrazinecarboxylate salt ‘sans’ the CO2 moiety. Salt formation involving pyridoxine (PN) yielded a salt hydrate with PAS (PN-PAS) and an anhydrous salt with PCBA (PN-PCBA). Both salts exhibited very complex packing arrangements with equally complex thermal behaviour depending on the solvent used during preparation, and the method of preparation. Three eutectic systems involving INH with PYR, PN and pyridoxine hydrochloride (PNꞏHCl) were identified, and their phase diagrams were constructed from DSC data. The eutectic compositions obtained were 1:1 for INH:PYR, 1:1 for INH:PN and 6:4 for INH:PNꞏHCl. Finally, a total of eight multicomponent complexes were prepared using selected API and vitamin B6 components. The results presented here provide motivation for further investigation and evaluation of the pharmacochemical properties of these API. , Thesis (MSc) -- Faculty of Science, Chemistry, 2024
- Full Text:
Comparative analysis of YOLOV5 and YOLOV8 for automated fish detection and classification in underwater environments
- Authors: Kuhlane, Luxolo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464333 , vital:76502
- Description: The application of traditional manual techniques for fish detection and classification faces significant challenges, primarily stemming from their labour-intensive nature and limited scalability. Automating these kinds of processes through computer vision practices and machine learning techniques has emerged as a potential solution in recent years. With the development of and increase in ease of access to new technology in recent years, the use of a deep learning object detector known as YOLO (You Only Look Once) in the detection and classification of fish has steadily become notably popular. This thesis thus explores suitable YOLO architectures for detecting and classifying fish. The YOLOv5 and YOLOv8 models were evaluated explicitly for detecting and classifying fish in underwater environments. The selection of these models was based on a literature review highlighting their success in similar applications but remains largely understudied in underwater environments. Therefore, the effectiveness of these models was evaluated through comprehensive experimentation on collected and publicly available underwater fish datasets. In collaboration with the South African Institute of Biodiversity (SAIAB), five datasets were collected and manually annotated for labels for supervised machine learning. Moreover, two publicly available datasets were sourced for comparison to the literature. Furthermore, after determining that the smallest YOLO architectures are better suited to these imbalanced datasets, hyperparameter tuning tailored the models to the characteristics of the various underwater environments used in the research. The popular DeepFish dataset was evaluated to establish a baseline and feasibility of these models in the understudied domain. The results demonstrated high detection accuracy for both YOLOv5 and YOLOv8. However, YOLOv8 outperformed YOLOv5, achieving 97.43% accuracy compared to 94.53%. After experiments on seven datasets, trends revealed YOLOv8’s enhanced generalisation accuracy due to architectural improvements, particularly in detecting smaller fish. Overall, YOLOv8 demonstrated that it is the better fish detection and classification model on diverse data. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
- Authors: Kuhlane, Luxolo
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/464333 , vital:76502
- Description: The application of traditional manual techniques for fish detection and classification faces significant challenges, primarily stemming from their labour-intensive nature and limited scalability. Automating these kinds of processes through computer vision practices and machine learning techniques has emerged as a potential solution in recent years. With the development of and increase in ease of access to new technology in recent years, the use of a deep learning object detector known as YOLO (You Only Look Once) in the detection and classification of fish has steadily become notably popular. This thesis thus explores suitable YOLO architectures for detecting and classifying fish. The YOLOv5 and YOLOv8 models were evaluated explicitly for detecting and classifying fish in underwater environments. The selection of these models was based on a literature review highlighting their success in similar applications but remains largely understudied in underwater environments. Therefore, the effectiveness of these models was evaluated through comprehensive experimentation on collected and publicly available underwater fish datasets. In collaboration with the South African Institute of Biodiversity (SAIAB), five datasets were collected and manually annotated for labels for supervised machine learning. Moreover, two publicly available datasets were sourced for comparison to the literature. Furthermore, after determining that the smallest YOLO architectures are better suited to these imbalanced datasets, hyperparameter tuning tailored the models to the characteristics of the various underwater environments used in the research. The popular DeepFish dataset was evaluated to establish a baseline and feasibility of these models in the understudied domain. The results demonstrated high detection accuracy for both YOLOv5 and YOLOv8. However, YOLOv8 outperformed YOLOv5, achieving 97.43% accuracy compared to 94.53%. After experiments on seven datasets, trends revealed YOLOv8’s enhanced generalisation accuracy due to architectural improvements, particularly in detecting smaller fish. Overall, YOLOv8 demonstrated that it is the better fish detection and classification model on diverse data. , Thesis (MSc) -- Faculty of Science, Computer Science, 2024
- Full Text:
Computational search for nature-derived dual-action inhibitors of HIV-1 reverse transcriptase and integrase: a potential strategy to mitigate drug resistance progression
- Authors: Mwiinga, Luyando
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463930 , vital:76458
- Description: Human immunodeficiency virus Type 1 (HIV-1) is a devastating viral infection affecting millions worldwide and presents significant challenges in treatment and management. In 2022, approximately 39 million people were living with HIV with Sub-Saharan Africa having two thirds of these infections. Devastatingly, there were approximately 300 000 HIV/AIDS related deaths in Sub-Saharan Africa alone in 2022 alone. Antiretroviral therapy (ART) which is fundamental for HIV treatment, comprises of a combination of drugs such as nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTs), protease inhibitors (PIs) and integrase strand transfer inhibitors (INSTIs). However, although 28.7 million people out of the estimated 38.4 million people living with HIV in 2021 were receiving ART, the emergence of drug-resistant strains further complicates treatment efforts, highlighting the need for novel therapeutic approaches. This study aimed to address the challenges raised by drug resistance and significant side effects by identifying potential dual inhibitors against HIV-1 Reverse Transcriptase (RT) and Integrase (IN) using in silico techniques. RT RNase H and IN were chosen as targets for their shared dependency on Mg2+ ions within their active sites, which are crucial for catalytic activity. The selection of dual inhibitors was motivated by the fact that the virus would need to replicate at two points simultaneously to develop resistance, making it less likely. The objectives of this study included the creation of a natural derivative compound library using RDKit with the aid of SciFinder, utilizing (-)-epigallocatechin-3-O-gallate (EGCG), because of its dual inhibitory effects against RT and IN, as indicated by a study conducted by Sanna et al. 2019. The natural derivatives were chosen to take advantage of their chemical diversity and to explore potential novel therapeutic options for combating HIV drug resistance. The compound library created comprised of 125 203 compounds. Then docking studies were conducted to assess proteinligand binding. After the correlation of the RT and IN docking studies, 288 compounds were filtered to have potential dual inhibitory activity. Then quantitative estimation of druggability (QED) analysis identified three compounds with superior properties compared to EGCG and FDAapproved drug raltegravir (RAL). Molecular docking simulations revealed interactions between the inhibitors and the key active site residues of RT and IN, along with the chelation of at least one 3 Mg2+, suggesting the potential for enzymatic disruption. Furthermore, molecular dynamic (MD) simulations were then conducted to assess protein-ligand system behavior, through RMSD and RMSF analysis. The RMSD analysis uncovered instability in the IN-Sci30703 complex, leading to its exclusion as a potential dual action inhibitor. RMSF analysis for IN showed that all the inhibitors had the ability to limit the flexibility of the catalytic loop which is essential for catalytic activity. Therefore, further in vitro studies are required to evaluate the effectiveness of the remaining two EGCG derivatives (Sci33211 and Sci48919) in inhibiting RT and IN through the chelation of at least one Mg2+ ion to determine if they have superior dual inhibitory effects compared to EGCG. This study adds to the ongoing efforts to develop effective strategies against HIV-1 drug resistance and emphasizes the importance of continued research in this field. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
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- Authors: Mwiinga, Luyando
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463930 , vital:76458
- Description: Human immunodeficiency virus Type 1 (HIV-1) is a devastating viral infection affecting millions worldwide and presents significant challenges in treatment and management. In 2022, approximately 39 million people were living with HIV with Sub-Saharan Africa having two thirds of these infections. Devastatingly, there were approximately 300 000 HIV/AIDS related deaths in Sub-Saharan Africa alone in 2022 alone. Antiretroviral therapy (ART) which is fundamental for HIV treatment, comprises of a combination of drugs such as nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTs), protease inhibitors (PIs) and integrase strand transfer inhibitors (INSTIs). However, although 28.7 million people out of the estimated 38.4 million people living with HIV in 2021 were receiving ART, the emergence of drug-resistant strains further complicates treatment efforts, highlighting the need for novel therapeutic approaches. This study aimed to address the challenges raised by drug resistance and significant side effects by identifying potential dual inhibitors against HIV-1 Reverse Transcriptase (RT) and Integrase (IN) using in silico techniques. RT RNase H and IN were chosen as targets for their shared dependency on Mg2+ ions within their active sites, which are crucial for catalytic activity. The selection of dual inhibitors was motivated by the fact that the virus would need to replicate at two points simultaneously to develop resistance, making it less likely. The objectives of this study included the creation of a natural derivative compound library using RDKit with the aid of SciFinder, utilizing (-)-epigallocatechin-3-O-gallate (EGCG), because of its dual inhibitory effects against RT and IN, as indicated by a study conducted by Sanna et al. 2019. The natural derivatives were chosen to take advantage of their chemical diversity and to explore potential novel therapeutic options for combating HIV drug resistance. The compound library created comprised of 125 203 compounds. Then docking studies were conducted to assess proteinligand binding. After the correlation of the RT and IN docking studies, 288 compounds were filtered to have potential dual inhibitory activity. Then quantitative estimation of druggability (QED) analysis identified three compounds with superior properties compared to EGCG and FDAapproved drug raltegravir (RAL). Molecular docking simulations revealed interactions between the inhibitors and the key active site residues of RT and IN, along with the chelation of at least one 3 Mg2+, suggesting the potential for enzymatic disruption. Furthermore, molecular dynamic (MD) simulations were then conducted to assess protein-ligand system behavior, through RMSD and RMSF analysis. The RMSD analysis uncovered instability in the IN-Sci30703 complex, leading to its exclusion as a potential dual action inhibitor. RMSF analysis for IN showed that all the inhibitors had the ability to limit the flexibility of the catalytic loop which is essential for catalytic activity. Therefore, further in vitro studies are required to evaluate the effectiveness of the remaining two EGCG derivatives (Sci33211 and Sci48919) in inhibiting RT and IN through the chelation of at least one Mg2+ ion to determine if they have superior dual inhibitory effects compared to EGCG. This study adds to the ongoing efforts to develop effective strategies against HIV-1 drug resistance and emphasizes the importance of continued research in this field. , Thesis (MSc) -- Faculty of Science, Biochemistry, Microbiology & Bioinformatics, 2024
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Connecting culture and science: Utilising Oshikundu and Ombidi in biology lessons on diffusion and osmosis
- Shilomboleni, Helena Ilena Ndilimeke
- Authors: Shilomboleni, Helena Ilena Ndilimeke
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463636 , vital:76427
- Description: Various science curricula including that of Namibia recommend that teaching and learning should start with the knowledge and experiences of learners from their homes and communities. These experiences are the learners’ Indigenous Knowledge (IK) which should be integrated to make science accessible and relevant to learners from diverse sociocultural backgrounds. This suggests that science teachers are encouraged to integrate IK into their teaching to help learners grasp abstract concepts and construct their own understanding of phenomena. However, much literature has revealed that many teachers find it difficult to integrate IK into their science teaching. Some scholars further argue that teachers lack the pedagogical content knowledge to effectively integrate IK. I assume this could be because the science curriculum is not explicit on how IK should be integrated into science teaching. It is against this backdrop that in this study I mobilised the Indigenous technologies of making oshikundu and preserving ombidi to support Grade 10 Biology learners in talking and making sense of diffusion and osmosis. This study was underpinned by the interpretivist and Indigenous research paradigms. Within the Indigenous research paradigm, I focused on Ubuntu as a perspective. A qualitative case study was employed and conducted at a certain school in the northern part of Namibia, in the Ohangwena region. I worked with a group of 35 Grade 10 learners, two Indigenous Knowledge Custodians (KCs) who are the custodians of cultural heritage and one Biology teacher (critical friend) as participants in this study. Qualitative data were collected using a focus group interview (sharing circle), group activity, participatory observation, and learners’ journal reflections. Vygotsky’s sociocultural theory together with Ogunniyi’s Contiguity Argumentative Theory were used as lenses to analyse data. The findings of the study revealed that during the IKCs’ practical demonstrations learners were able to identify science concepts embedded in the cultural practices of making oshikundu and preserving ombidi. The findings further revealed that the practical demonstrations enhanced active participation and interactions among learners. I thus recommend that teachers should tap into IKCs’ cultural heritage by inviting them into their classrooms to make science relevant, accessible and meaningful to learners. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text:
- Authors: Shilomboleni, Helena Ilena Ndilimeke
- Date: 2024-10-11
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/463636 , vital:76427
- Description: Various science curricula including that of Namibia recommend that teaching and learning should start with the knowledge and experiences of learners from their homes and communities. These experiences are the learners’ Indigenous Knowledge (IK) which should be integrated to make science accessible and relevant to learners from diverse sociocultural backgrounds. This suggests that science teachers are encouraged to integrate IK into their teaching to help learners grasp abstract concepts and construct their own understanding of phenomena. However, much literature has revealed that many teachers find it difficult to integrate IK into their science teaching. Some scholars further argue that teachers lack the pedagogical content knowledge to effectively integrate IK. I assume this could be because the science curriculum is not explicit on how IK should be integrated into science teaching. It is against this backdrop that in this study I mobilised the Indigenous technologies of making oshikundu and preserving ombidi to support Grade 10 Biology learners in talking and making sense of diffusion and osmosis. This study was underpinned by the interpretivist and Indigenous research paradigms. Within the Indigenous research paradigm, I focused on Ubuntu as a perspective. A qualitative case study was employed and conducted at a certain school in the northern part of Namibia, in the Ohangwena region. I worked with a group of 35 Grade 10 learners, two Indigenous Knowledge Custodians (KCs) who are the custodians of cultural heritage and one Biology teacher (critical friend) as participants in this study. Qualitative data were collected using a focus group interview (sharing circle), group activity, participatory observation, and learners’ journal reflections. Vygotsky’s sociocultural theory together with Ogunniyi’s Contiguity Argumentative Theory were used as lenses to analyse data. The findings of the study revealed that during the IKCs’ practical demonstrations learners were able to identify science concepts embedded in the cultural practices of making oshikundu and preserving ombidi. The findings further revealed that the practical demonstrations enhanced active participation and interactions among learners. I thus recommend that teachers should tap into IKCs’ cultural heritage by inviting them into their classrooms to make science relevant, accessible and meaningful to learners. , Thesis (MEd) -- Faculty of Education, Secondary and Post-School Education, 2024
- Full Text: