Investigating a new wealth tax in South Africa: Lessons from international experience
- Arendse, Jacqueline A, Stack, Elizabeth M
- Authors: Arendse, Jacqueline A , Stack, Elizabeth M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69434 , vital:29536 , https://jefjournal.org.za/index.php/jef/article/view/175/193
- Description: In recent years, there has been an increasing focus on new sources of taxation, including wealth tax. In South Africa, two phenomena have driven the focus on wealth tax. Firstly, the need for additional tax revenue to fund an ongoing and growing budget deficit, exacerbated by a prolonged period of low economic growth, rising government debt and a very small base of individual taxpayers. Secondly, the fact that South Africa has one of the most unequal societies in the world. The dual demands of increased tax revenue and economic inequality have converged around wealth tax as a possible panacea to both problems. Although South Africa has a long history of wealth transfer tax in the form of estate duty and donations tax, there has never been a tax on the net wealth holdings of individuals during their lifetime. Internationally, numerous countries have used wealth tax in various forms, including inheritance tax, gift tax, recurrent wealth tax and non-recurrent wealth tax. This study examines some of the international experiences with these three categories of wealth tax, seeking lessons and experiences that can inform the debate around the viability of a new wealth tax in South Africa.
- Full Text:
- Authors: Arendse, Jacqueline A , Stack, Elizabeth M
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69434 , vital:29536 , https://jefjournal.org.za/index.php/jef/article/view/175/193
- Description: In recent years, there has been an increasing focus on new sources of taxation, including wealth tax. In South Africa, two phenomena have driven the focus on wealth tax. Firstly, the need for additional tax revenue to fund an ongoing and growing budget deficit, exacerbated by a prolonged period of low economic growth, rising government debt and a very small base of individual taxpayers. Secondly, the fact that South Africa has one of the most unequal societies in the world. The dual demands of increased tax revenue and economic inequality have converged around wealth tax as a possible panacea to both problems. Although South Africa has a long history of wealth transfer tax in the form of estate duty and donations tax, there has never been a tax on the net wealth holdings of individuals during their lifetime. Internationally, numerous countries have used wealth tax in various forms, including inheritance tax, gift tax, recurrent wealth tax and non-recurrent wealth tax. This study examines some of the international experiences with these three categories of wealth tax, seeking lessons and experiences that can inform the debate around the viability of a new wealth tax in South Africa.
- Full Text:
Investigating combinations of feature extraction and classification for improved image-based multimodal biometric systems at the feature level
- Authors: Brown, Dane L
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63470 , vital:28414
- Description: Multimodal biometrics has become a popular means of overcoming the limitations of unimodal biometric systems. However, the rich information particular to the feature level is of a complex nature and leveraging its potential without overfitting a classifier is not well studied. This research investigates feature-classifier combinations on the fingerprint, face, palmprint, and iris modalities to effectively fuse their feature vectors for a complementary result. The effects of different feature-classifier combinations are thus isolated to identify novel or improved algorithms. A new face segmentation algorithm is shown to increase consistency in nominal and extreme scenarios. Moreover, two novel feature extraction techniques demonstrate better adaptation to dynamic lighting conditions, while reducing feature dimensionality to the benefit of classifiers. A comprehensive set of unimodal experiments are carried out to evaluate both verification and identification performance on a variety of datasets using four classifiers, namely Eigen, Fisher, Local Binary Pattern Histogram and linear Support Vector Machine on various feature extraction methods. The recognition performance of the proposed algorithms are shown to outperform the vast majority of related studies, when using the same dataset under the same test conditions. In the unimodal comparisons presented, the proposed approaches outperform existing systems even when given a handicap such as fewer training samples or data with a greater number of classes. A separate comprehensive set of experiments on feature fusion show that combining modality data provides a substantial increase in accuracy, with only a few exceptions that occur when differences in the image data quality of two modalities are substantial. However, when two poor quality datasets are fused, noticeable gains in recognition performance are realized when using the novel feature extraction approach. Finally, feature-fusion guidelines are proposed to provide the necessary insight to leverage the rich information effectively when fusing multiple biometric modalities at the feature level. These guidelines serve as the foundation to better understand and construct biometric systems that are effective in a variety of applications.
- Full Text:
- Authors: Brown, Dane L
- Date: 2018
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63470 , vital:28414
- Description: Multimodal biometrics has become a popular means of overcoming the limitations of unimodal biometric systems. However, the rich information particular to the feature level is of a complex nature and leveraging its potential without overfitting a classifier is not well studied. This research investigates feature-classifier combinations on the fingerprint, face, palmprint, and iris modalities to effectively fuse their feature vectors for a complementary result. The effects of different feature-classifier combinations are thus isolated to identify novel or improved algorithms. A new face segmentation algorithm is shown to increase consistency in nominal and extreme scenarios. Moreover, two novel feature extraction techniques demonstrate better adaptation to dynamic lighting conditions, while reducing feature dimensionality to the benefit of classifiers. A comprehensive set of unimodal experiments are carried out to evaluate both verification and identification performance on a variety of datasets using four classifiers, namely Eigen, Fisher, Local Binary Pattern Histogram and linear Support Vector Machine on various feature extraction methods. The recognition performance of the proposed algorithms are shown to outperform the vast majority of related studies, when using the same dataset under the same test conditions. In the unimodal comparisons presented, the proposed approaches outperform existing systems even when given a handicap such as fewer training samples or data with a greater number of classes. A separate comprehensive set of experiments on feature fusion show that combining modality data provides a substantial increase in accuracy, with only a few exceptions that occur when differences in the image data quality of two modalities are substantial. However, when two poor quality datasets are fused, noticeable gains in recognition performance are realized when using the novel feature extraction approach. Finally, feature-fusion guidelines are proposed to provide the necessary insight to leverage the rich information effectively when fusing multiple biometric modalities at the feature level. These guidelines serve as the foundation to better understand and construct biometric systems that are effective in a variety of applications.
- Full Text:
Investigating Grade 3 learners’ changing mathematical proficiency in a maths club programme focused on number sense progression
- Authors: Hebe, Gasenakeletso Ennie
- Date: 2018
- Subjects: Mathematical ability -- Testing , Education, Elementary -- South Africa , Mathematics -- Study and teaching (Elementary) -- Activity programs , Mathematics -- Remedial teaching , South African Numeracy Chair Project (SANCP)
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/62200 , vital:28137
- Description: Recent international reports, for example TIMSS (2011 & 2015), point to serious challenges in South African learner performance in Mathematics and Science. Of greatest concern is that research findings (e.g. Graven, Venkat, Westaway and Tshesane 2013) suggest that many South African learners show signs of mathematical knowledge gaps in the lower grades. Hence, there is a need to address challenges of this nature very early in Foundation Phase. This study was undertaken with a view to contribute towards addressing mathematical challenges encountered by learners in Foundation Phase. This empirical enquiry was undertaken under the auspices of the South African Numeracy Chair Project (SANCP) at Rhodes University whose mission is to develop sustainable ways of improving quality teaching and learning of Mathematics in South Africa. A relatively new SANCP programme called Pushing for Progression (PfP) run as part of the after-school Maths Clubs to develop the number sense and four Operations in learners was used to achieve the research aims of this study. Research participants were drawn from the Maths Clubs established by the researcher in a small rural town of Ottosdal in the North West Province of South Africa. This Study is grounded on the Vygotskian perspective and uses the interpretivist qualitative research method for data collection and analysis. Sampling was done opportunistically by enlisting participants (12 teachers and 117 learners) on the basis of their availability and willingness to participate. Pre- and post-assessment of learners’ proficiency on the four Basic Operations was conducted at the beginning and at the end of the research project, respectively. This was done to determine the impact of the project on learner performance. Data analysis was done thematically and through the comparison of learner results of the pre- and post-assessment. The findings point to the effectiveness of the PfP Programme in learner performance. This can be deduced from improved scores between pre- and post-assessment and the observations made by participant-teachers on their respective club learners’ mathematical proficiencies. Accordingly, based on the findings, this study recommends, inter alia, that since the PfP programme is still in its early stages, similar research be conducted elsewhere. Additionally, the Department of Basic Education could consider exploring the PfP programme as one of several other strategies to help improve learner proficiency in Mathematics.
- Full Text:
- Authors: Hebe, Gasenakeletso Ennie
- Date: 2018
- Subjects: Mathematical ability -- Testing , Education, Elementary -- South Africa , Mathematics -- Study and teaching (Elementary) -- Activity programs , Mathematics -- Remedial teaching , South African Numeracy Chair Project (SANCP)
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/62200 , vital:28137
- Description: Recent international reports, for example TIMSS (2011 & 2015), point to serious challenges in South African learner performance in Mathematics and Science. Of greatest concern is that research findings (e.g. Graven, Venkat, Westaway and Tshesane 2013) suggest that many South African learners show signs of mathematical knowledge gaps in the lower grades. Hence, there is a need to address challenges of this nature very early in Foundation Phase. This study was undertaken with a view to contribute towards addressing mathematical challenges encountered by learners in Foundation Phase. This empirical enquiry was undertaken under the auspices of the South African Numeracy Chair Project (SANCP) at Rhodes University whose mission is to develop sustainable ways of improving quality teaching and learning of Mathematics in South Africa. A relatively new SANCP programme called Pushing for Progression (PfP) run as part of the after-school Maths Clubs to develop the number sense and four Operations in learners was used to achieve the research aims of this study. Research participants were drawn from the Maths Clubs established by the researcher in a small rural town of Ottosdal in the North West Province of South Africa. This Study is grounded on the Vygotskian perspective and uses the interpretivist qualitative research method for data collection and analysis. Sampling was done opportunistically by enlisting participants (12 teachers and 117 learners) on the basis of their availability and willingness to participate. Pre- and post-assessment of learners’ proficiency on the four Basic Operations was conducted at the beginning and at the end of the research project, respectively. This was done to determine the impact of the project on learner performance. Data analysis was done thematically and through the comparison of learner results of the pre- and post-assessment. The findings point to the effectiveness of the PfP Programme in learner performance. This can be deduced from improved scores between pre- and post-assessment and the observations made by participant-teachers on their respective club learners’ mathematical proficiencies. Accordingly, based on the findings, this study recommends, inter alia, that since the PfP programme is still in its early stages, similar research be conducted elsewhere. Additionally, the Department of Basic Education could consider exploring the PfP programme as one of several other strategies to help improve learner proficiency in Mathematics.
- Full Text:
Investigating the influence of ring substitution on indole hydrogen bonding, with amino acids
- Authors: Nel, Donovan
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63509 , vital:28426
- Description: Expected release date-April 2019
- Full Text: false
- Authors: Nel, Donovan
- Date: 2018
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63509 , vital:28426
- Description: Expected release date-April 2019
- Full Text: false
Investigating the viability and performance of a pilot scale Fly Ash/Lime Filter Tower (FLFT) for greywater treatment and the fate of Triclosan post treatment
- Authors: Nondlazi, Sinoyolo
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63704 , vital:28473
- Description: Expected release date-April 2020
- Full Text:
- Authors: Nondlazi, Sinoyolo
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63704 , vital:28473
- Description: Expected release date-April 2020
- Full Text:
Investigating thermal physiology as a tool to improve the release efficacy of insect biological control agents
- Authors: Griffith, Tamzin Camilla
- Date: 2018
- Subjects: Aquatic weeds -- Biological control , Water hyacinth -- Biological control , Insects -- Physiology , Miridae -- Effect of low temperatures on , Cold adaptation , Insects as biological pest control agents , Eccritotarsus catarinensis
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63301 , vital:28391
- Description: Biological control is commonly used for the control of invasive aquatic weeds, which often involves the release of multiple host-specific agents. Releasing multiple agents has inherent safety concerns as the introduction of each new agent is associated with risks, but is often required to improve control where establishment is limited. Climatic incompatibility between the agent’s thermal physiology and its introduced range often causes agents to fail to establish. However, it has been suggested that the thermal physiology of insects is plastic. Therefore, the potential to manipulate their thermal physiologies before releasing them into the field needs to be explored; reducing the need to release additional agents, thereby ensuring the safety of biological control. This thesis therefore aimed to firstly, determine whether season and locality influenced the thermal physiology of two field populations of a water hyacinth (Eichhornia crassipes) control agent, the mirid Eccritotarsus catarinensis; one collected from the hottest establishment site, and one collected from the coldest establishment site in South Africa. Their thermal physiology was significantly influenced by season and not by the sites’ climate, suggesting their thermal physiology is plastic under field conditions. Secondly, the classical method of determining the lower critical thermal limit (CTmin), and a new respirometry method of determining this limit, compared the thermal physiology of two Eccritotarsus species reared in quarantine. Eccritotarsus catarinensis was significantly more cold tolerant than the more recently released Eccritotarsus eichhorniae, despite similar maintenance conditions, and as such, was used to establish whether cold hardening under laboratory conditions was possible. Successfully cold hardened E. catarinensis had a significantly lower CTmin compared to the field cold acclimated population, suggesting that cold hardening of agents could be conducted before release to improve their cold tolerance and increase their chances of establishment, allowing for further adaptation to colder climates in the field to occur. Increasing establishment of the most effective agents will decrease the number of agents needed in a biological control programme, thus encouraging a more parsimonious approach to biological control.
- Full Text:
- Authors: Griffith, Tamzin Camilla
- Date: 2018
- Subjects: Aquatic weeds -- Biological control , Water hyacinth -- Biological control , Insects -- Physiology , Miridae -- Effect of low temperatures on , Cold adaptation , Insects as biological pest control agents , Eccritotarsus catarinensis
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/63301 , vital:28391
- Description: Biological control is commonly used for the control of invasive aquatic weeds, which often involves the release of multiple host-specific agents. Releasing multiple agents has inherent safety concerns as the introduction of each new agent is associated with risks, but is often required to improve control where establishment is limited. Climatic incompatibility between the agent’s thermal physiology and its introduced range often causes agents to fail to establish. However, it has been suggested that the thermal physiology of insects is plastic. Therefore, the potential to manipulate their thermal physiologies before releasing them into the field needs to be explored; reducing the need to release additional agents, thereby ensuring the safety of biological control. This thesis therefore aimed to firstly, determine whether season and locality influenced the thermal physiology of two field populations of a water hyacinth (Eichhornia crassipes) control agent, the mirid Eccritotarsus catarinensis; one collected from the hottest establishment site, and one collected from the coldest establishment site in South Africa. Their thermal physiology was significantly influenced by season and not by the sites’ climate, suggesting their thermal physiology is plastic under field conditions. Secondly, the classical method of determining the lower critical thermal limit (CTmin), and a new respirometry method of determining this limit, compared the thermal physiology of two Eccritotarsus species reared in quarantine. Eccritotarsus catarinensis was significantly more cold tolerant than the more recently released Eccritotarsus eichhorniae, despite similar maintenance conditions, and as such, was used to establish whether cold hardening under laboratory conditions was possible. Successfully cold hardened E. catarinensis had a significantly lower CTmin compared to the field cold acclimated population, suggesting that cold hardening of agents could be conducted before release to improve their cold tolerance and increase their chances of establishment, allowing for further adaptation to colder climates in the field to occur. Increasing establishment of the most effective agents will decrease the number of agents needed in a biological control programme, thus encouraging a more parsimonious approach to biological control.
- Full Text:
Investigation of molecular mechanism of recognition between citral and MARK4: A newer therapeutic approach to attenuate cancer cell progression
- Naz, Farha, Khan, Faez I, Mohammad, Taj, Khan, Parvez, Manzoor, Saaliqa, Hasan, Gulam M, Lobb, Kevin A, Luqman, Suaib, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Naz, Farha , Khan, Faez I , Mohammad, Taj , Khan, Parvez , Manzoor, Saaliqa , Hasan, Gulam M , Lobb, Kevin A , Luqman, Suaib , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447967 , vital:74687 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.10.143"
- Description: Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100 ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.
- Full Text:
- Authors: Naz, Farha , Khan, Faez I , Mohammad, Taj , Khan, Parvez , Manzoor, Saaliqa , Hasan, Gulam M , Lobb, Kevin A , Luqman, Suaib , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447967 , vital:74687 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.10.143"
- Description: Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100 ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.
- Full Text:
Iron (iii) porphyrin electrocatalyzed enantioselective carbon-chloride bond cleavage of hexachlorocyclohexanes (HCHs): combined experimental investigation and theoretical calculations
- Liang, Xu, Li, Minzhi, Mack, John, Lobb, Kevin A, Zhu, Weihua
- Authors: Liang, Xu , Li, Minzhi , Mack, John , Lobb, Kevin A , Zhu, Weihua
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447979 , vital:74688 , xlink:href="https://pubs.rsc.org/en/content/articlehtml/2018/dt/c8dt02510j"
- Description: Enantioselective electrocatalysis of α-, β-, γ- and δ-hexachlorocyclohexanes (HCHs) by tetrakis-pentafluorophenyl-Fe(III)porphyrin is described. The first example of the combined use of electrochemical measurements and theoretical calculations to determine the mechanism of the enantioselective C–Cl bond cleavage of the electrocatalysis is reported. The electrochemical measurements demonstrate that the reactivity of the HCHs follows the order γ-HCH > α-HCH > δ-HCH > β-HCH. Steric considerations and a molecular orbital theory approach can be used to rationalize the enantioselective nature of the catalysis based on the ease of approach of each Cl atom to the central Fe(I) ion and a consideration of the nodes on the C–Cl bonds that weaken these bonds in a manner that results in bond cleavage and the formation of an Fe–Cl bond.
- Full Text:
- Authors: Liang, Xu , Li, Minzhi , Mack, John , Lobb, Kevin A , Zhu, Weihua
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447979 , vital:74688 , xlink:href="https://pubs.rsc.org/en/content/articlehtml/2018/dt/c8dt02510j"
- Description: Enantioselective electrocatalysis of α-, β-, γ- and δ-hexachlorocyclohexanes (HCHs) by tetrakis-pentafluorophenyl-Fe(III)porphyrin is described. The first example of the combined use of electrochemical measurements and theoretical calculations to determine the mechanism of the enantioselective C–Cl bond cleavage of the electrocatalysis is reported. The electrochemical measurements demonstrate that the reactivity of the HCHs follows the order γ-HCH > α-HCH > δ-HCH > β-HCH. Steric considerations and a molecular orbital theory approach can be used to rationalize the enantioselective nature of the catalysis based on the ease of approach of each Cl atom to the central Fe(I) ion and a consideration of the nodes on the C–Cl bonds that weaken these bonds in a manner that results in bond cleavage and the formation of an Fe–Cl bond.
- Full Text:
Isolation and Characterisation of Stigmasterol and β–Sitosterol from Anthocleista djalonensis A. Chev.
- Okoro, Ijeoma S, Tor-Anyiin, Terrumun A, Igoli, John O, Noundou, Xavier S, Krause, Rui W M
- Authors: Okoro, Ijeoma S , Tor-Anyiin, Terrumun A , Igoli, John O , Noundou, Xavier S , Krause, Rui W M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126191 , vital:35857 , https://doi.org/10.9734/AJOCS/2017/37147
- Description: Aim: Anthocleista djalonensis A. Chev. is a plant with several chemical constituents whichaccounts for its ethno-pharmacological uses. The present study is aimed at identifying and characterizing the active principles from the roots of the plant. Place and Duration of Study: The study was carried out at the Department of Organic Chemistry,Rhodes University, Grahamstown, South Africa between March and July 2016. Methodology: The root powder was subjected to maceration with methanol to obtain the crude extract. The methanol extract was fractionated using hexane, ethyl acetate and acetone successively. The acetone extract was thereafter subjected to column chromatography to isolate any pure components. Results: White needle-like crystals were obtained which on spectral analysis(IR, 1H NMR, 13C NMR, 2D- NMR, and ESI-MS ) were identified as a mixture of stigmasterol and β-sitosterol. Conclusion: The compounds isolated were identified as stigmasterol and β-sitosterol.
- Full Text:
- Authors: Okoro, Ijeoma S , Tor-Anyiin, Terrumun A , Igoli, John O , Noundou, Xavier S , Krause, Rui W M
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126191 , vital:35857 , https://doi.org/10.9734/AJOCS/2017/37147
- Description: Aim: Anthocleista djalonensis A. Chev. is a plant with several chemical constituents whichaccounts for its ethno-pharmacological uses. The present study is aimed at identifying and characterizing the active principles from the roots of the plant. Place and Duration of Study: The study was carried out at the Department of Organic Chemistry,Rhodes University, Grahamstown, South Africa between March and July 2016. Methodology: The root powder was subjected to maceration with methanol to obtain the crude extract. The methanol extract was fractionated using hexane, ethyl acetate and acetone successively. The acetone extract was thereafter subjected to column chromatography to isolate any pure components. Results: White needle-like crystals were obtained which on spectral analysis(IR, 1H NMR, 13C NMR, 2D- NMR, and ESI-MS ) were identified as a mixture of stigmasterol and β-sitosterol. Conclusion: The compounds isolated were identified as stigmasterol and β-sitosterol.
- Full Text:
Isolation, identification and genetic characterisation of a microsporidium isolated from the carob moth, Ectomyelois ceratoniae (Lepidoptera: Pyralidae)
- Authors: Lloyd, Melissa
- Date: 2018
- Subjects: Pyralidae , Pyralidae -- Genetics , Pyralidae -- Phylogeny , Pyralidae -- Pathogens , Cladistic analysis , Transmission electron microscopy , Carob moth (Ectomyelois ceratoniae)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61894 , vital:28075
- Description: Carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae) is an economically important pest, yet its biology and pest status on citrus in South Africa was, until recently, poorly understood. A study was initiated to determine the cause of collapse of a laboratory carob moth colony that was established to investigate the biology of carob moth on citrus and to develop integrated management strategies for the pest. An organism was isolated from deceased larvae and was morphologically identified as a microsporidium, based on transmission electron microscopy. Microsporidia are obligate intracellular parasites that have been found to infect almost all eukaryotes. Several Nosema species have been isolated from economically important insect pests, yet little genetic information is available from online databases for identification. Mature spores were recovered and measured using transmission electron microscopy. Spores were ovocylindrical with a wrinkled exospore, and had a length of 2.8 ± 0.02 pm and a width of 1.6 ± 0.04 pm. The identity of the microsporidium was confirmed by PCR amplification, sequencing and analysis of the regions encoding the ribosomal RNA. BLAST analysis of the different rRNA regions amplified showed that the microsporidium shared a 96 - 99 % identity with Nosema sp. M-Pr, Nosema carpocapsae, Nosema oulemae, Nosema sp. CO1, Microsporidium 57864, and Nosema bombi. Phylogenetic analysis of the SSU and LSU rRNA genes showed that the microsporidium clustered with the Nosema / Vairimorpha clade, supported by a bootstrap value of 100. The organisation of the RNA cistron was determined by PCR amplification using the primer set 18f and L1328r to be 5’-SSU-ITS-LSU-IGS-5S-3’, which confirms the placement of the microsporidium within the Nosema / Vairimorpha clade. Because the BLAST results showed a close relationship with Nosema carpocapsae, a microsporidium infecting codling moth, the pathogenicity of the microsporidium was tested against codling moth by inoculating artificial diet with a high spore concentration of 1.1 x 107 spores/ml and a low spore concentration of 1.1 x 104 spores/ml. DNA was extracted from deceased larvae inoculated with the high concentration, and PCR of the SSU rRNA gene and bacterial 16S region was performed. Mortality in the high concentration experiment was significant (p = 0.05), but the cause of infection was determined to be a bacterium, through sequencing and BLAST analysis of the bacterial 16S rDNA. The bacterium shared a 99 % identity with Bacillus cereus. Percentage mortality (p = 0.09), larval mass (p = 0.09) and instar (p = 0.24) did not differ significantly between treatments in the low concentration experiment. DNA was extracted from the larvae and PCR amplification of the SSU rRNA gene was performed to determine whether microsporidia were present. No SSU bands were observed in any of the treatments and percentage mortality was not significant, thus it was determined that no infection occurred. This is the first study to report the genetic characterisation of a microsporidium isolated from carob moth and provides important genetic information for classification of microsporidia within the Nosema / Vairimorpha clade. It is also one of few studies in which the complete rRNA cistron of a species within the Nosema / Vairimorpha clade has been sequenced. The identification of a microsporidium from a laboratory colony of carob moth is important as it provides information about pathogens infecting the carob moth and constraints to carob moth rearing, which is useful for further studies on rearing carob moth and for establishment of a clean colony for research purposes.
- Full Text:
- Authors: Lloyd, Melissa
- Date: 2018
- Subjects: Pyralidae , Pyralidae -- Genetics , Pyralidae -- Phylogeny , Pyralidae -- Pathogens , Cladistic analysis , Transmission electron microscopy , Carob moth (Ectomyelois ceratoniae)
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/61894 , vital:28075
- Description: Carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae) is an economically important pest, yet its biology and pest status on citrus in South Africa was, until recently, poorly understood. A study was initiated to determine the cause of collapse of a laboratory carob moth colony that was established to investigate the biology of carob moth on citrus and to develop integrated management strategies for the pest. An organism was isolated from deceased larvae and was morphologically identified as a microsporidium, based on transmission electron microscopy. Microsporidia are obligate intracellular parasites that have been found to infect almost all eukaryotes. Several Nosema species have been isolated from economically important insect pests, yet little genetic information is available from online databases for identification. Mature spores were recovered and measured using transmission electron microscopy. Spores were ovocylindrical with a wrinkled exospore, and had a length of 2.8 ± 0.02 pm and a width of 1.6 ± 0.04 pm. The identity of the microsporidium was confirmed by PCR amplification, sequencing and analysis of the regions encoding the ribosomal RNA. BLAST analysis of the different rRNA regions amplified showed that the microsporidium shared a 96 - 99 % identity with Nosema sp. M-Pr, Nosema carpocapsae, Nosema oulemae, Nosema sp. CO1, Microsporidium 57864, and Nosema bombi. Phylogenetic analysis of the SSU and LSU rRNA genes showed that the microsporidium clustered with the Nosema / Vairimorpha clade, supported by a bootstrap value of 100. The organisation of the RNA cistron was determined by PCR amplification using the primer set 18f and L1328r to be 5’-SSU-ITS-LSU-IGS-5S-3’, which confirms the placement of the microsporidium within the Nosema / Vairimorpha clade. Because the BLAST results showed a close relationship with Nosema carpocapsae, a microsporidium infecting codling moth, the pathogenicity of the microsporidium was tested against codling moth by inoculating artificial diet with a high spore concentration of 1.1 x 107 spores/ml and a low spore concentration of 1.1 x 104 spores/ml. DNA was extracted from deceased larvae inoculated with the high concentration, and PCR of the SSU rRNA gene and bacterial 16S region was performed. Mortality in the high concentration experiment was significant (p = 0.05), but the cause of infection was determined to be a bacterium, through sequencing and BLAST analysis of the bacterial 16S rDNA. The bacterium shared a 99 % identity with Bacillus cereus. Percentage mortality (p = 0.09), larval mass (p = 0.09) and instar (p = 0.24) did not differ significantly between treatments in the low concentration experiment. DNA was extracted from the larvae and PCR amplification of the SSU rRNA gene was performed to determine whether microsporidia were present. No SSU bands were observed in any of the treatments and percentage mortality was not significant, thus it was determined that no infection occurred. This is the first study to report the genetic characterisation of a microsporidium isolated from carob moth and provides important genetic information for classification of microsporidia within the Nosema / Vairimorpha clade. It is also one of few studies in which the complete rRNA cistron of a species within the Nosema / Vairimorpha clade has been sequenced. The identification of a microsporidium from a laboratory colony of carob moth is important as it provides information about pathogens infecting the carob moth and constraints to carob moth rearing, which is useful for further studies on rearing carob moth and for establishment of a clean colony for research purposes.
- Full Text:
Jazz in service of the struggle: the New Brighton story
- Authors: Thram, Diane J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/481842 , vital:78590 , https://doi.org/10.21504/amj.v10i4.2234
- Description: This article contributes to the substantial body of publications on South African jazz with information on jazz performance and performers in New Brighton, a township adjacent to Port Elizabeth noted for its vibrant jazz scene and outstanding jazz musicians. The article covers several decades from the heyday of swing bands in the 1940s—50s through the 1960s—70s when New Brighton's premier jazz combo, the Soul Jazzmen, were at the height of their artistry. The role of swing bands in New Brighton and surrounding communities as the training ground for members of the Soul Jazzmen and other local musicians of note is discussed, as well as how the Soul Jazzmen in turn were tutors for musicians of the next generation who became widely recognized artists, composers and arrangers. This is followed by a focus on the Soul Jazzmen and compositions by its members that protested against the apartheid regime in the 1960s—70s. The article is informed by historic photographs, newspaper clippings and information from oral history interviews that richly document how jazz was performed in service of the anti-apartheid struggle in New Brighton.
- Full Text:
- Authors: Thram, Diane J
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/481842 , vital:78590 , https://doi.org/10.21504/amj.v10i4.2234
- Description: This article contributes to the substantial body of publications on South African jazz with information on jazz performance and performers in New Brighton, a township adjacent to Port Elizabeth noted for its vibrant jazz scene and outstanding jazz musicians. The article covers several decades from the heyday of swing bands in the 1940s—50s through the 1960s—70s when New Brighton's premier jazz combo, the Soul Jazzmen, were at the height of their artistry. The role of swing bands in New Brighton and surrounding communities as the training ground for members of the Soul Jazzmen and other local musicians of note is discussed, as well as how the Soul Jazzmen in turn were tutors for musicians of the next generation who became widely recognized artists, composers and arrangers. This is followed by a focus on the Soul Jazzmen and compositions by its members that protested against the apartheid regime in the 1960s—70s. The article is informed by historic photographs, newspaper clippings and information from oral history interviews that richly document how jazz was performed in service of the anti-apartheid struggle in New Brighton.
- Full Text:
Jesus, Che, Luaty: on the relationship between a digital picture and an iconic image in political iconography in Angola
- Authors: Siegert, Nadine
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145919 , vital:38478 , DOI: 10.2979/africatoday.65.1.04
- Description: This essay makes a close examination of a selection of images of the Angolan rapper Luaty Beirão, who became internationally known as a political activist during his imprisonment in June 2015, accused of staging a coup d'état. By analyzing and interpreting images that were highly mediatized during that period, this article shows how political iconography can be traced back to Christian iconography and other images. Such filiations of images and their mediatization invoke a power that contributes to the formation of political and popular icons. This article analyzes this nexus by deconstructing the transmutation of a photograph into a popular icon.
- Full Text:
- Authors: Siegert, Nadine
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145919 , vital:38478 , DOI: 10.2979/africatoday.65.1.04
- Description: This essay makes a close examination of a selection of images of the Angolan rapper Luaty Beirão, who became internationally known as a political activist during his imprisonment in June 2015, accused of staging a coup d'état. By analyzing and interpreting images that were highly mediatized during that period, this article shows how political iconography can be traced back to Christian iconography and other images. Such filiations of images and their mediatization invoke a power that contributes to the formation of political and popular icons. This article analyzes this nexus by deconstructing the transmutation of a photograph into a popular icon.
- Full Text:
Judging psycholegal reporting in civil court proceedings in the Eastern Cape
- Authors: Marais, Claire Anne
- Date: 2018
- Subjects: Court proceedings -- South Africa -- Eastern Cape , Evidence, Expert -- South Africa -- Eastern Cape , Forensic psychology -- South Africa -- Eastern Cape , Quality Rating Scale (QRS) , Psycholegal reporting -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/62999 , vital:28352
- Description: Purpose: The primary purpose for this research was to evaluate the quality of psycholegal reports, and the qualification of the authors. Previous research had revealed generalised poor practices in psycholegal report writing and the authors seemed unqualified as expert witness. This negatively influenced the impression and usefulness of expert psychological opinion in South African courts. The secondary purpose was to compare the results to those determined by Ireland (2012), which was a useful benchmark study in the UK as her findings corresponded with the literature. Method: This archival research analysed a hand-search sample of 20 reports written by 20 psychologists based nationally. These reports were submitted as expert opinion in civil proceedings in the Grahamstown Division of the Eastern Cape High Court between 2011 and 2016. Ireland and Pinschof’s (2009) measure ‘Quality Rating Scale’ was adapted for a South African context and used to evaluate quantitatively the reports. Focus was on the reports’ contents (fact and opinion), methods, process and overall rating, and the qualification of the authors. Results: Overall, two-thirds of the reports were rated as ‘good’ and ‘very good’. The results were generally more positive than Ireland’s (2012) findings. However, there were practices in the report writing that were deemed detrimental to the quality of the expert’s opinion. This included vague referral questions and unclear basis for concluding opinions and diagnosis. There was also a lack of discussions surrounding the scientific trustworthiness of testing methods and absent ethical considerations. Lastly, the specialised expertise of the experts was not adequately documented. Conclusion: The findings painted a more positive picture of psycholegal reporting in South Africa than illustrated in previous research, which seemingly relied on anecdotes and subjective surveys. This study used a systematic and objective measure. The findings of this study, previous research and ethical Rules of Conduct were used to consider recommendations for psycholegal report writing, and the improvement of the field of psycholegal work. Lastly, the focus of future research was discussed.
- Full Text:
- Authors: Marais, Claire Anne
- Date: 2018
- Subjects: Court proceedings -- South Africa -- Eastern Cape , Evidence, Expert -- South Africa -- Eastern Cape , Forensic psychology -- South Africa -- Eastern Cape , Quality Rating Scale (QRS) , Psycholegal reporting -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/62999 , vital:28352
- Description: Purpose: The primary purpose for this research was to evaluate the quality of psycholegal reports, and the qualification of the authors. Previous research had revealed generalised poor practices in psycholegal report writing and the authors seemed unqualified as expert witness. This negatively influenced the impression and usefulness of expert psychological opinion in South African courts. The secondary purpose was to compare the results to those determined by Ireland (2012), which was a useful benchmark study in the UK as her findings corresponded with the literature. Method: This archival research analysed a hand-search sample of 20 reports written by 20 psychologists based nationally. These reports were submitted as expert opinion in civil proceedings in the Grahamstown Division of the Eastern Cape High Court between 2011 and 2016. Ireland and Pinschof’s (2009) measure ‘Quality Rating Scale’ was adapted for a South African context and used to evaluate quantitatively the reports. Focus was on the reports’ contents (fact and opinion), methods, process and overall rating, and the qualification of the authors. Results: Overall, two-thirds of the reports were rated as ‘good’ and ‘very good’. The results were generally more positive than Ireland’s (2012) findings. However, there were practices in the report writing that were deemed detrimental to the quality of the expert’s opinion. This included vague referral questions and unclear basis for concluding opinions and diagnosis. There was also a lack of discussions surrounding the scientific trustworthiness of testing methods and absent ethical considerations. Lastly, the specialised expertise of the experts was not adequately documented. Conclusion: The findings painted a more positive picture of psycholegal reporting in South Africa than illustrated in previous research, which seemingly relied on anecdotes and subjective surveys. This study used a systematic and objective measure. The findings of this study, previous research and ethical Rules of Conduct were used to consider recommendations for psycholegal report writing, and the improvement of the field of psycholegal work. Lastly, the focus of future research was discussed.
- Full Text:
Key considerations for novel aptamer generation and aptasensor platform design: a case study on human α-thrombin and histamine as sensor targets
- Authors: Ho, Lance St John
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63534 , vital:28432
- Description: Expected release date-April 2020
- Full Text:
- Authors: Ho, Lance St John
- Date: 2018
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/63534 , vital:28432
- Description: Expected release date-April 2020
- Full Text:
Knowledge and knowers in Educational Leadership and Management (ELM) Master’s Programmes in South Africa
- Authors: Kajee, Farhana Amod
- Date: 2018
- Subjects: Educational leadership -- South Africa , Teachers -- Training of -- South Africa , Education, Higher -- South Africa , Master of education degree -- South Africa , Knowledge, Theory of , Educational sociology -- South Africa , Education, Higher -- Aims and objectives -- South Africa , Legitimation Code Theory (LCT)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/60698 , vital:27819
- Description: This dissertation examines the knowledge and knower practices in the Master’s in Educational Leadership and Management (ELM) coursework programmes at South African public universities. This study was prompted by my growing awareness of problems and tensions in the field of ELM generally, and at the level of programme design of the M Ed degree in particular. Many of these had been identified by a national audit of coursework M Eds in ELM (CHE, 2010), and this study sought to find a way of theorising these with a view to improving both course design and teaching. To this end I employed Maton’s Legitimation Code Theory (LCT) which enables critical engagement with knowledge and knowers in programmes, how they are positioned, and how this positioning may be problematic. Hence my first research question sought to discover and critique what counted as knowledge in these programmes and why, while the second asked how knowers were positioned, and why this had come to be the case. LCT has its roots in the work of Bernstein and Maton, whose preoccupation with curriculum was/is driven by a sense of social justice: if we can understand how and why the curriculum is organised and presented in a particular way, it becomes possible to re-imagine teaching and learning, making it accessible to a broader, more inclusive body of learners. The study also drew on critical realism as an underlabourer. This philosophy provided a nuanced understanding of ontology, encouraging and enabling me, as researcher, to unearth causal mechanisms driving the status quo. Only seven South African universities currently offer the coursework option of a Master’s degree in ELM, compared to thirteen when the audit was conducted in 2010. Six of the universities agreed to take part in the study. Data was gathered through content analysis of the six course outlines and interviews with individual co-ordinators or academics centrally involved in the programmes. Through the development of a translation device I was able to establishing that a knower code was dominant in the programmes. Using this point as my departure, I interrogated the knowledge practices and found that different types of knowledge were being privileged across the programmes, with some having a practical/professional leaning and others a more academic/theoretical orientation. The resultant tension does, I argue, restrict knowledge building and helps to account for the fact that the field is generally considered to be under-theorised. The fact all of these programme are registered with the same national qualifications authority, ostensibly following the same national guidelines for Master’s degrees is worrying. The study attempts to find underlying, historically significant reasons for this unevenness. An analysis of the programmes revealed a leaning towards supportive pedagogical approaches. While all programmes promote a cultivated gaze their purposes are not always the same. While a hegemonic practices potential for opening counts as knowledge, cultivated gaze can enable transformation, it can also encourage that can impede real change and empowerment. The study has the up much needed debate on what is meant by a Master’s in ELM, what and what kinds of knower are envisaged.
- Full Text:
- Authors: Kajee, Farhana Amod
- Date: 2018
- Subjects: Educational leadership -- South Africa , Teachers -- Training of -- South Africa , Education, Higher -- South Africa , Master of education degree -- South Africa , Knowledge, Theory of , Educational sociology -- South Africa , Education, Higher -- Aims and objectives -- South Africa , Legitimation Code Theory (LCT)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/60698 , vital:27819
- Description: This dissertation examines the knowledge and knower practices in the Master’s in Educational Leadership and Management (ELM) coursework programmes at South African public universities. This study was prompted by my growing awareness of problems and tensions in the field of ELM generally, and at the level of programme design of the M Ed degree in particular. Many of these had been identified by a national audit of coursework M Eds in ELM (CHE, 2010), and this study sought to find a way of theorising these with a view to improving both course design and teaching. To this end I employed Maton’s Legitimation Code Theory (LCT) which enables critical engagement with knowledge and knowers in programmes, how they are positioned, and how this positioning may be problematic. Hence my first research question sought to discover and critique what counted as knowledge in these programmes and why, while the second asked how knowers were positioned, and why this had come to be the case. LCT has its roots in the work of Bernstein and Maton, whose preoccupation with curriculum was/is driven by a sense of social justice: if we can understand how and why the curriculum is organised and presented in a particular way, it becomes possible to re-imagine teaching and learning, making it accessible to a broader, more inclusive body of learners. The study also drew on critical realism as an underlabourer. This philosophy provided a nuanced understanding of ontology, encouraging and enabling me, as researcher, to unearth causal mechanisms driving the status quo. Only seven South African universities currently offer the coursework option of a Master’s degree in ELM, compared to thirteen when the audit was conducted in 2010. Six of the universities agreed to take part in the study. Data was gathered through content analysis of the six course outlines and interviews with individual co-ordinators or academics centrally involved in the programmes. Through the development of a translation device I was able to establishing that a knower code was dominant in the programmes. Using this point as my departure, I interrogated the knowledge practices and found that different types of knowledge were being privileged across the programmes, with some having a practical/professional leaning and others a more academic/theoretical orientation. The resultant tension does, I argue, restrict knowledge building and helps to account for the fact that the field is generally considered to be under-theorised. The fact all of these programme are registered with the same national qualifications authority, ostensibly following the same national guidelines for Master’s degrees is worrying. The study attempts to find underlying, historically significant reasons for this unevenness. An analysis of the programmes revealed a leaning towards supportive pedagogical approaches. While all programmes promote a cultivated gaze their purposes are not always the same. While a hegemonic practices potential for opening counts as knowledge, cultivated gaze can enable transformation, it can also encourage that can impede real change and empowerment. The study has the up much needed debate on what is meant by a Master’s in ELM, what and what kinds of knower are envisaged.
- Full Text:
Knowledge practices and student access and success in General Chemistry at a Large South African University
- Authors: Mtombeni, Thabile Nokuthula
- Date: 2018
- Subjects: Chemistry -- Study and teaching (Higher) -- South Africa , Knowledge management , Education, Higher -- Curricula -- South Africa , Critical realism , Social integration -- South Africa , Educational equalization -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62873 , vital:28305
- Description: This dissertation reports on an investigation into the structuring principles of the General Chemistry curriculum at a Large South African University (LSAU). Student learning in the introductory modules of General Chemistry is critical for access to a range of fields since it is a requisite course for a variety of degree programmes. However, there is ample evidence that success in this subject remains a major challenge, particularly for black students. My quest in this study was to explore how the curriculum could enable greater epistemic access and thus include more students in science programmes at the LSAU. I investigated the organising principles underlying the curriculum practices of the General Chemistry module and explored the effects of the curriculum structure on student learning. Theoretically and conceptually, the study was underpinned by a social realist approach which holds that knowledge is stratified, differentiated, and has real emergent properties, powers and effects. The research question that I attempted to answer in this study was: How do knowledge practices privileged in the General Chemistry curriculum at the LSAU enable or constrain student learning? I adopted an intensive research design approach to conduct a qualitative case study using social realism and LCT as theoretical and analytical lenses. I used empirical data such as curriculum documents and interviews with lecturers to uncover the underlying generative mechanisms of the curriculum. I adopted a multi-layered data analysis process to make visible the underlying organising principles informing knowledge practices in the curriculum so that I could explain their potential effects on student learning. The first level of analysis explored the context of the curriculum and associated knowledge practices, and examined the pedagogic discourse evident in the curriculum. The second level of analysis revealed the inner logic structuring the curriculum and the associated knowledge practices. I used Maton’s Legitimation Code Theory (LCT): Specialisation to identify the specialisation codes, gazes and insights generated by the curriculum. For the third level of analysis, LCT: Semantics was used to generate the semantic profiles of learning activities to determine the extent to which the curriculum structure made cumulative learning possible. From the findings, it is evident that the verticality of knowledge in General Chemistry points to a recontextualising principle that prescribes the selection and arrangement of knowledge, and the special relationship of actors and discourses. As a result, the strong framing of the instructional discourse of General Chemistry curriculum structure is likely to constrain epistemological access for large numbers of students. In order to improve epistemological access to the field, weaker framing of the instructional discourse in introductory science is necessary. Weaker framing of the General Chemistry curriculum would require, in particular, changes to pacing, and that the evaluative criteria are made explicit. This is especially necessary when certain abstract and complex curricular content is taught, especially in the first semester. The findings also indicate that the nature of the organising principles in the curriculum are significant for improving epistemological access to knowledge. In terms of LCT: Specialisation, the General Chemistry curriculum generated a knowledge code and downplayed differences among social categories of students, thus positioning all equally in relation to the knowledge and practices of the field. Therefore, the structuring of the curriculum emphasises and legitimates students who have attained specialist knowledge without considering the nature of the new student coming into the educational setting. Simply, what is privileged is both the object of study (theoretical knowledge) and how it is studied (procedural knowledge). This finding is in line with the general outcomes of Chemistry education. In addition, the purist insight generated by the curriculum further attests to where the emphasis is placed in the curriculum. I argue that the lack of social relations in the curriculum poses a challenge for the holistic development of students as science knowers. The analysis of the learning activities shows rapid code shifts that indicate changes in cognitive demand and modes of thinking required of students. I argue that signposting the changes in complexity of knowledge and in the mode of thinking required could make learning, and thus epistemological access, more possible. Given the imperative of access to powerful knowledge, I contend that the curriculum should be reshaped to enable epistemological access for more students.
- Full Text:
- Authors: Mtombeni, Thabile Nokuthula
- Date: 2018
- Subjects: Chemistry -- Study and teaching (Higher) -- South Africa , Knowledge management , Education, Higher -- Curricula -- South Africa , Critical realism , Social integration -- South Africa , Educational equalization -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/62873 , vital:28305
- Description: This dissertation reports on an investigation into the structuring principles of the General Chemistry curriculum at a Large South African University (LSAU). Student learning in the introductory modules of General Chemistry is critical for access to a range of fields since it is a requisite course for a variety of degree programmes. However, there is ample evidence that success in this subject remains a major challenge, particularly for black students. My quest in this study was to explore how the curriculum could enable greater epistemic access and thus include more students in science programmes at the LSAU. I investigated the organising principles underlying the curriculum practices of the General Chemistry module and explored the effects of the curriculum structure on student learning. Theoretically and conceptually, the study was underpinned by a social realist approach which holds that knowledge is stratified, differentiated, and has real emergent properties, powers and effects. The research question that I attempted to answer in this study was: How do knowledge practices privileged in the General Chemistry curriculum at the LSAU enable or constrain student learning? I adopted an intensive research design approach to conduct a qualitative case study using social realism and LCT as theoretical and analytical lenses. I used empirical data such as curriculum documents and interviews with lecturers to uncover the underlying generative mechanisms of the curriculum. I adopted a multi-layered data analysis process to make visible the underlying organising principles informing knowledge practices in the curriculum so that I could explain their potential effects on student learning. The first level of analysis explored the context of the curriculum and associated knowledge practices, and examined the pedagogic discourse evident in the curriculum. The second level of analysis revealed the inner logic structuring the curriculum and the associated knowledge practices. I used Maton’s Legitimation Code Theory (LCT): Specialisation to identify the specialisation codes, gazes and insights generated by the curriculum. For the third level of analysis, LCT: Semantics was used to generate the semantic profiles of learning activities to determine the extent to which the curriculum structure made cumulative learning possible. From the findings, it is evident that the verticality of knowledge in General Chemistry points to a recontextualising principle that prescribes the selection and arrangement of knowledge, and the special relationship of actors and discourses. As a result, the strong framing of the instructional discourse of General Chemistry curriculum structure is likely to constrain epistemological access for large numbers of students. In order to improve epistemological access to the field, weaker framing of the instructional discourse in introductory science is necessary. Weaker framing of the General Chemistry curriculum would require, in particular, changes to pacing, and that the evaluative criteria are made explicit. This is especially necessary when certain abstract and complex curricular content is taught, especially in the first semester. The findings also indicate that the nature of the organising principles in the curriculum are significant for improving epistemological access to knowledge. In terms of LCT: Specialisation, the General Chemistry curriculum generated a knowledge code and downplayed differences among social categories of students, thus positioning all equally in relation to the knowledge and practices of the field. Therefore, the structuring of the curriculum emphasises and legitimates students who have attained specialist knowledge without considering the nature of the new student coming into the educational setting. Simply, what is privileged is both the object of study (theoretical knowledge) and how it is studied (procedural knowledge). This finding is in line with the general outcomes of Chemistry education. In addition, the purist insight generated by the curriculum further attests to where the emphasis is placed in the curriculum. I argue that the lack of social relations in the curriculum poses a challenge for the holistic development of students as science knowers. The analysis of the learning activities shows rapid code shifts that indicate changes in cognitive demand and modes of thinking required of students. I argue that signposting the changes in complexity of knowledge and in the mode of thinking required could make learning, and thus epistemological access, more possible. Given the imperative of access to powerful knowledge, I contend that the curriculum should be reshaped to enable epistemological access for more students.
- Full Text:
Kowieria alveoformis gen. nov. sp. nov., a new heterosporous lycophyte from the Latest Devonian of Southern Africa
- Gess, Robert W, Prestianni, Cyrille
- Authors: Gess, Robert W , Prestianni, Cyrille
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/73894 , vital:30239 , https://doi.org/10.1016/j.revpalbo.2017.10.002
- Description: A new lycopsid, Kowieria alveoformis gen. et sp. nov., is described from the FamennianWitpoort Formation, Grahamstown, South Africa. It possesses spirally arranged elongated falcate vegetative leaves. Terminal bisporangiate strobili are present and show loosely grouped micro- and megasporophylls. Sporophylls are similar in shape to the vegetative leaves though somewhat wider with a marked expansion to house the sporangium. One sporangium is attached directly to the adaxial surface of the lamina. Each megasporangium contains up to four heavily ornamented hologulate megaspores of the Lagenicula type. The combination of both basal and derived characters within this plant places it at an interesting position at the base of the phylogenetic tree of rhizomorphic lycopsids.
- Full Text:
- Authors: Gess, Robert W , Prestianni, Cyrille
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/73894 , vital:30239 , https://doi.org/10.1016/j.revpalbo.2017.10.002
- Description: A new lycopsid, Kowieria alveoformis gen. et sp. nov., is described from the FamennianWitpoort Formation, Grahamstown, South Africa. It possesses spirally arranged elongated falcate vegetative leaves. Terminal bisporangiate strobili are present and show loosely grouped micro- and megasporophylls. Sporophylls are similar in shape to the vegetative leaves though somewhat wider with a marked expansion to house the sporangium. One sporangium is attached directly to the adaxial surface of the lamina. Each megasporangium contains up to four heavily ornamented hologulate megaspores of the Lagenicula type. The combination of both basal and derived characters within this plant places it at an interesting position at the base of the phylogenetic tree of rhizomorphic lycopsids.
- Full Text:
Language as source of revitalisation and reclamation of Indigenous epistemologies.
- Authors: Maseko, Pamela
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/468413 , vital:77052 , ISBN 9781928314110
- Description: While history, art and archaeology, for example, have been used to present evidence of socio-cultural and other practices of precolonial Africa, the contribution of language as a source from which one can make presuppositions and conjectures about its speakers’ past has not been sufficiently explored. In a context where African knowledge has been undermined and misinterpreted by scholars whose inclination is to scrutinise African experience from a prejudiced cultural standpoint, the study of the meanings embedded in the lexicon of African languages cannot be overlooked when lifting the veil from Africa’s past. Although meanings of words in a language may shift because of contact with other linguistic societies, or because of new domains of language use, one is able to study the etymology of words to elicit original meanings and their evolution in form and meaning, and also make correspond-ence of such meanings to the thoughts of society as early as present memory can recall.
- Full Text:
- Authors: Maseko, Pamela
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/468413 , vital:77052 , ISBN 9781928314110
- Description: While history, art and archaeology, for example, have been used to present evidence of socio-cultural and other practices of precolonial Africa, the contribution of language as a source from which one can make presuppositions and conjectures about its speakers’ past has not been sufficiently explored. In a context where African knowledge has been undermined and misinterpreted by scholars whose inclination is to scrutinise African experience from a prejudiced cultural standpoint, the study of the meanings embedded in the lexicon of African languages cannot be overlooked when lifting the veil from Africa’s past. Although meanings of words in a language may shift because of contact with other linguistic societies, or because of new domains of language use, one is able to study the etymology of words to elicit original meanings and their evolution in form and meaning, and also make correspond-ence of such meanings to the thoughts of society as early as present memory can recall.
- Full Text:
Largest reported groups for the Indo-Pacific bottlenose dolphin (Tursiops aduncus) found in Algoa Bay, South Africa: trends and potential drivers
- Bouveroux, Thibaut N, Caputo, Michelle, Froneman, P William, Plön, Stephanie
- Authors: Bouveroux, Thibaut N , Caputo, Michelle , Froneman, P William , Plön, Stephanie
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67913 , vital:29168 , https://doi.org/10.1111/mms.12471
- Description: Publisher version , This study investigates how group size of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) changes temporally, spatially, and/or with predominant behavior at two discreet sites along the Eastern Cape coastline of South Africa: Algoa Bay and the Wild Coast. The mean group size of bottlenose dolphins was large with an average of 52 animals. Significantly larger groups were observed in Algoa Bay ( = 60, range = 1–600) than off the Wild Coast ( = 32.9, range = 1–250). In Algoa Bay, the mean group size increased significantly over the study period, from an average 18 animals in 2008 to 76 animals in 2016. Additionally, the largest average and maximum group sizes ever reported both in South Africa and worldwide, were recorded in Algoa Bay (maximum group size = 600). Neither season nor behavior had a significant effect on mean group size at both sites. Similarly environmental variables such as the depth and substrate type also had no influence on group size. It remains unclear which ecological drivers, such as predation risk and food availability, are leading to the large groups observed in this area, and further research on abundance and distribution of both predators and prey is necessary.
- Full Text: false
- Authors: Bouveroux, Thibaut N , Caputo, Michelle , Froneman, P William , Plön, Stephanie
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67913 , vital:29168 , https://doi.org/10.1111/mms.12471
- Description: Publisher version , This study investigates how group size of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) changes temporally, spatially, and/or with predominant behavior at two discreet sites along the Eastern Cape coastline of South Africa: Algoa Bay and the Wild Coast. The mean group size of bottlenose dolphins was large with an average of 52 animals. Significantly larger groups were observed in Algoa Bay ( = 60, range = 1–600) than off the Wild Coast ( = 32.9, range = 1–250). In Algoa Bay, the mean group size increased significantly over the study period, from an average 18 animals in 2008 to 76 animals in 2016. Additionally, the largest average and maximum group sizes ever reported both in South Africa and worldwide, were recorded in Algoa Bay (maximum group size = 600). Neither season nor behavior had a significant effect on mean group size at both sites. Similarly environmental variables such as the depth and substrate type also had no influence on group size. It remains unclear which ecological drivers, such as predation risk and food availability, are leading to the large groups observed in this area, and further research on abundance and distribution of both predators and prey is necessary.
- Full Text: false
Leadership development within a Learner Representative Council (LRC) in a rural secondary school in the Oshana region, Namibia
- Authors: Da Silva, Rolens
- Date: 2018
- Subjects: Student participation in administration Namibia , Student government Namibia , Educational leadership Namibia , Qualitative research
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/62808 , vital:28282
- Description: The Namibian Education Act (Namibia. Education Act No. 16 of 2001) mandates state secondary school learners to be included in school leadership through a body of learners known as the Learner Representative Council (LRC). The few studies carried out on the LRC in schools reveal that very little has been achieved in terms of learner leadership development. This study explored and provided insight into possible reasons for this, and recommendations. The research questions driving the study were: How is learner leadership currently understood and practised in the school? What are the enabling and constraining factors in the school as far as learner leadership development is concerned? And what can be done to promote learner leadership development? This study is an interpretive case study of learner leadership in the LRC in a Namibian state secondary school in the Oshana region. The conceptual framework used was distributed leadership. The Cultural Historical Activity Theory (CHAT) was used as an analytical tool. The research participants were the LRC members, school principal, Heads of Departments representing the school management members, the School Board Chairperson representing parents and the LRC liaison teacher and were all purposively selected. Data was collected through document analysis, open-ended questionnaires, interviews and non-participant observation. Data analysis took the form of inductively – identifying themes emerged from the data and deductively – using CHAT to surface the systemic contradictions within the learners’ activity system. The data revealed that learner leadership was mostly understood from a management perspective and equated with the formal authority of the LRC in the school. The data further revealed that the LRC performed more leadership roles stretched from inside the classroom, outside the classroom, on the School Board and outside the school. To capture this complexity, I developed a model which may prove useful for future studies of learner leadership. The data also indicated that much support was offered to the LRC members in the school; for example, support from the LRC liaison teacher, the School Management Team and generally from the school, through LRC leadership training. Using CHAT, the findings revealed that the historical context and cultural conventions contradicted the LRC leadership development in the school. In line with a distributed leadership theory, the study recommends that learner leadership should not be limited by position and authority but should be exercised by all learners, through the development and establishment of learner leader clubs in the school. The study also recommends that schools should embark on change initiatives which challenge their traditionally held beliefs and attitudes.
- Full Text:
- Authors: Da Silva, Rolens
- Date: 2018
- Subjects: Student participation in administration Namibia , Student government Namibia , Educational leadership Namibia , Qualitative research
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/62808 , vital:28282
- Description: The Namibian Education Act (Namibia. Education Act No. 16 of 2001) mandates state secondary school learners to be included in school leadership through a body of learners known as the Learner Representative Council (LRC). The few studies carried out on the LRC in schools reveal that very little has been achieved in terms of learner leadership development. This study explored and provided insight into possible reasons for this, and recommendations. The research questions driving the study were: How is learner leadership currently understood and practised in the school? What are the enabling and constraining factors in the school as far as learner leadership development is concerned? And what can be done to promote learner leadership development? This study is an interpretive case study of learner leadership in the LRC in a Namibian state secondary school in the Oshana region. The conceptual framework used was distributed leadership. The Cultural Historical Activity Theory (CHAT) was used as an analytical tool. The research participants were the LRC members, school principal, Heads of Departments representing the school management members, the School Board Chairperson representing parents and the LRC liaison teacher and were all purposively selected. Data was collected through document analysis, open-ended questionnaires, interviews and non-participant observation. Data analysis took the form of inductively – identifying themes emerged from the data and deductively – using CHAT to surface the systemic contradictions within the learners’ activity system. The data revealed that learner leadership was mostly understood from a management perspective and equated with the formal authority of the LRC in the school. The data further revealed that the LRC performed more leadership roles stretched from inside the classroom, outside the classroom, on the School Board and outside the school. To capture this complexity, I developed a model which may prove useful for future studies of learner leadership. The data also indicated that much support was offered to the LRC members in the school; for example, support from the LRC liaison teacher, the School Management Team and generally from the school, through LRC leadership training. Using CHAT, the findings revealed that the historical context and cultural conventions contradicted the LRC leadership development in the school. In line with a distributed leadership theory, the study recommends that learner leadership should not be limited by position and authority but should be exercised by all learners, through the development and establishment of learner leader clubs in the school. The study also recommends that schools should embark on change initiatives which challenge their traditionally held beliefs and attitudes.
- Full Text: