Investigating multi-thread utilization as a software defence mechanism against side channel attacks
- Frieslaar, Ibraheem, Irwin, Barry V W
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430190 , vital:72672 , https://doi.org/10.1145/3015166.3015176
- Description: A state-of-the-art software countermeasure to defend against side channel attacks is investigated in this work. The implementation of this novel approach consists of using multi-threads and a task scheduler on a microcontroller to purposefully leak out information at critical points in the cryptographic algorithm and confuse the attacker. This research demonstrates it is capable of outperforming the known countermeasure of hiding and shuffling in terms of preventing the secret information from being leaked out. Furthermore, the proposed countermeasure mitigates the side channel attacks, such as correlation power analysis and template attacks.
- Full Text:
- Date Issued: 2016
- Authors: Frieslaar, Ibraheem , Irwin, Barry V W
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430190 , vital:72672 , https://doi.org/10.1145/3015166.3015176
- Description: A state-of-the-art software countermeasure to defend against side channel attacks is investigated in this work. The implementation of this novel approach consists of using multi-threads and a task scheduler on a microcontroller to purposefully leak out information at critical points in the cryptographic algorithm and confuse the attacker. This research demonstrates it is capable of outperforming the known countermeasure of hiding and shuffling in terms of preventing the secret information from being leaked out. Furthermore, the proposed countermeasure mitigates the side channel attacks, such as correlation power analysis and template attacks.
- Full Text:
- Date Issued: 2016
Investigating soil microbial interactions of Portulacaria afra
- Authors: Fulmaka, Aviwe
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54598 , vital:26592
- Description: Portulacaria afra commonly known as Spekboom contributes significantly to carbon sequestration and has been widely planted in degraded areas of the Eastern Cape. Approximately 50% of planted cuttings do not survive although the cause of this decline is unknown. Like many indigenous plants, Spekboom forms a symbiotic relationship with mycorrhizal fungi and the interaction with rhizobacteria may enhance and improve plant growth and establishment. This study aims to investigate these relationships which will include a survey of the arbuscular mycorrhizal (AM) fungal populations associated with Spekboom, determination of the causal agent of Spekboom decline, isolation and identification of the associated rhizobacteria and investigation of their plant growth promotion properties and assessing the ability of arbuscular mycorrhizal fungi and selected rhizobacteria to enhance establishment and growth of Spekboom. Soil and root samples from selected trial sites were used to assess AM fungal spore abundance and colonisation; isolation, characterization, and identification of rhizobacteria and determine the interaction of the microbes on Spekboom growth and tolerance to Fusarium. AM spore abundance and percentage root colonisation did not differ between the three Spekboom plots. Molecular analyses of the SSU region from the plots showed 4 families of AM fungi and were identified as Ambisporaceae, Glomeraceae, Claroideoglomeraceae and Paraglomeraceae. A suspected Fusarium pathogen was isolated and molecularly identified. Pathogenicity tests indicated reduced Spekboom growth with poor root development. Thirty four rhizobacterial isolates were tested for various plant growth promoting abilities. Of these, 6 were able to produce IAA which may promote plant root growth, 27 siderophores and 23 were phosphate solubilisers. Bacterial isolates were molecularly identified to be from various species of Bacillus, with some Arthrobacter, Enterobacter, Pseudomonas and Microbacterium. Inoculation of Spekboom cuttings with mycorrhizal fungi and selected rhizobacterial isolates significantly improved shoot height. Spekboom cuttings challenged with Fusarium and inoculated with mycorrhizal fungi and two rhizobacterial isolates significantly improved growth. The inoculation of cuttings in the nursery with mycorrhizal fungi and selected rhizobacteria is recommended prior to establishing Spekboom in the field.
- Full Text:
- Date Issued: 2016
- Authors: Fulmaka, Aviwe
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54598 , vital:26592
- Description: Portulacaria afra commonly known as Spekboom contributes significantly to carbon sequestration and has been widely planted in degraded areas of the Eastern Cape. Approximately 50% of planted cuttings do not survive although the cause of this decline is unknown. Like many indigenous plants, Spekboom forms a symbiotic relationship with mycorrhizal fungi and the interaction with rhizobacteria may enhance and improve plant growth and establishment. This study aims to investigate these relationships which will include a survey of the arbuscular mycorrhizal (AM) fungal populations associated with Spekboom, determination of the causal agent of Spekboom decline, isolation and identification of the associated rhizobacteria and investigation of their plant growth promotion properties and assessing the ability of arbuscular mycorrhizal fungi and selected rhizobacteria to enhance establishment and growth of Spekboom. Soil and root samples from selected trial sites were used to assess AM fungal spore abundance and colonisation; isolation, characterization, and identification of rhizobacteria and determine the interaction of the microbes on Spekboom growth and tolerance to Fusarium. AM spore abundance and percentage root colonisation did not differ between the three Spekboom plots. Molecular analyses of the SSU region from the plots showed 4 families of AM fungi and were identified as Ambisporaceae, Glomeraceae, Claroideoglomeraceae and Paraglomeraceae. A suspected Fusarium pathogen was isolated and molecularly identified. Pathogenicity tests indicated reduced Spekboom growth with poor root development. Thirty four rhizobacterial isolates were tested for various plant growth promoting abilities. Of these, 6 were able to produce IAA which may promote plant root growth, 27 siderophores and 23 were phosphate solubilisers. Bacterial isolates were molecularly identified to be from various species of Bacillus, with some Arthrobacter, Enterobacter, Pseudomonas and Microbacterium. Inoculation of Spekboom cuttings with mycorrhizal fungi and selected rhizobacterial isolates significantly improved shoot height. Spekboom cuttings challenged with Fusarium and inoculated with mycorrhizal fungi and two rhizobacterial isolates significantly improved growth. The inoculation of cuttings in the nursery with mycorrhizal fungi and selected rhizobacteria is recommended prior to establishing Spekboom in the field.
- Full Text:
- Date Issued: 2016
Investigating the role of the South African Schools Choral Eisteddfod in introducing learners to music career
- Authors: Sibene, Vuyelwa
- Date: 2016
- Subjects: Choral music -- South Africa , Choral singing -- Instruction and study -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26382 , vital:65298
- Description: This research investigates the role of South African Schools Choral Eisteddfod (SASCE) in introducing learners in high schools to music career. It attempts to identify learners in grade 12 who want to study music at university and students who were involved in SASCE and are now in university. These learners and students have limited music background and are/were involved in the South African Schools Choral Eisteddfod (SASCE) program. Within the study, I felt to also include a graduated music student to validate the study. The study proceeds with the investigation by exploring numerous areas such as SASCE as a music program, music education, music careers, national curriculum, music literacy etc. Also, I write about the background to the study in which I share my motivation and experiences about the SASCE programme and how it influenced me and other former SASCE participants’ decisions about musical careers. Data collection is executed through the involvement of the sampled learner and students through participating in semi-structured interview, document analysis and personal observations. Four interviews which were in qualitative method were conducted with 4 participants, one interview each participant was in a semi-structure form. Interviews were aimed in recognizing the current status of the learner/students in music literacy and are they coping in their respected places of study. The data is analyzed using a qualitative analyses technique. Further, the study outlines problems and one research question of the investigation, 'To which extent do University music students with limited music background succeed or fail to obtain their music degrees?’. , Thesis (BMUS) -- Faculty of Humanities, 2016
- Full Text:
- Date Issued: 2016
- Authors: Sibene, Vuyelwa
- Date: 2016
- Subjects: Choral music -- South Africa , Choral singing -- Instruction and study -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/26382 , vital:65298
- Description: This research investigates the role of South African Schools Choral Eisteddfod (SASCE) in introducing learners in high schools to music career. It attempts to identify learners in grade 12 who want to study music at university and students who were involved in SASCE and are now in university. These learners and students have limited music background and are/were involved in the South African Schools Choral Eisteddfod (SASCE) program. Within the study, I felt to also include a graduated music student to validate the study. The study proceeds with the investigation by exploring numerous areas such as SASCE as a music program, music education, music careers, national curriculum, music literacy etc. Also, I write about the background to the study in which I share my motivation and experiences about the SASCE programme and how it influenced me and other former SASCE participants’ decisions about musical careers. Data collection is executed through the involvement of the sampled learner and students through participating in semi-structured interview, document analysis and personal observations. Four interviews which were in qualitative method were conducted with 4 participants, one interview each participant was in a semi-structure form. Interviews were aimed in recognizing the current status of the learner/students in music literacy and are they coping in their respected places of study. The data is analyzed using a qualitative analyses technique. Further, the study outlines problems and one research question of the investigation, 'To which extent do University music students with limited music background succeed or fail to obtain their music degrees?’. , Thesis (BMUS) -- Faculty of Humanities, 2016
- Full Text:
- Date Issued: 2016
Investigating the use of Arbuscular Mycorrhizas and Plant Growth Promoting Bacteria to improve the drought tolerance of maize (Zea mays L.)
- Authors: Moore, Nicolle Maureen
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54587 , vital:26591
- Description: Maize (Zea mays L.) is a direct staple food crop in Africa and remains an essential component of global food security, with maize crops accounting for over 60% of the total harvested area of annual food crops. Stress caused by drought and high soil salinity limits crop growth and productivity more than any other single environmental factor, with grain yield reductions up to 76% depending on the severity of the drought and the plant growth stage. Arbuscular mycorrhizal (AM) fungi and Plant Growth Promotion Rhizobacteria (PGPR) have previously been shown to improve tolerance of plants to drought stress through a number of chemical and physiological processes. The aim of this investigation was to determine whether mycorrhizal fungi and rhizobacteria adapted to drought and saline conditions and possessing plant growth promoting (PGP) traits were able to stimulate plant growth responses when applied to Zea mays seeds growing under greenhouse conditions Bacterial isolates selected were tolerant to concentrations of NaCl up to 600 mM and maintained 50% growth at low water potentials (-1.44 MPa). They were positive for Indole Acetic Acid (IAA) production, phosphate solubilisation and secretion of siderophores. Bacterial isolates showing plant growth promoting potential were identified using 16S rDNA gene sequencing as Achromobacter xylosoxidans strains A8 and C54 and Klebsiella oxytoca strain M1. Mixed inoculum was prepared from indigenous communities of mycorrhizas in soils sampled from the Cerebos Salt Pan and the Kalahari Desert. Mycorrhizal diversity was investigated using 454-Pyrosequencing which revealed that the community composition was dominated by species in the Ambispora, Glomus and Paraglomus genera with a rare component represented by species in the Redeckera, Archaeospora and Geosiphon genera. Microscopic examination of plant roots at the end of the trial revealed the presence of diagnostic mycorrhizal structures within the root cells, confirming that colonization was successful. Plant growth response to microbial inoculation was assessed by monitoring changes in plant photosynthetic capacity over the duration of a 7 week pot trial. A significant difference in photosynthetic and biomass data was observed between drought and well-watered groups but no mycorrhizal or bacterial treatment effect was evident within the groups, despite the high levels of colonization by mycorrhizas. These results suggest that the beneficial effects of mycorrhizal colonization may be primarily attributed to improved nutrient and mineral uptake in conditions where nutrients are limiting, resulting in improved growth. The improved growth may then have secondary effects on the plant‟s ability to withstand drought. Having controlled for nutrient deficiency, it was not evident in this study that mycorrhizal fungi were able to stimulate a change in plant physiology and confer drought tolerance under the conditions imposed.
- Full Text:
- Date Issued: 2016
- Authors: Moore, Nicolle Maureen
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/54587 , vital:26591
- Description: Maize (Zea mays L.) is a direct staple food crop in Africa and remains an essential component of global food security, with maize crops accounting for over 60% of the total harvested area of annual food crops. Stress caused by drought and high soil salinity limits crop growth and productivity more than any other single environmental factor, with grain yield reductions up to 76% depending on the severity of the drought and the plant growth stage. Arbuscular mycorrhizal (AM) fungi and Plant Growth Promotion Rhizobacteria (PGPR) have previously been shown to improve tolerance of plants to drought stress through a number of chemical and physiological processes. The aim of this investigation was to determine whether mycorrhizal fungi and rhizobacteria adapted to drought and saline conditions and possessing plant growth promoting (PGP) traits were able to stimulate plant growth responses when applied to Zea mays seeds growing under greenhouse conditions Bacterial isolates selected were tolerant to concentrations of NaCl up to 600 mM and maintained 50% growth at low water potentials (-1.44 MPa). They were positive for Indole Acetic Acid (IAA) production, phosphate solubilisation and secretion of siderophores. Bacterial isolates showing plant growth promoting potential were identified using 16S rDNA gene sequencing as Achromobacter xylosoxidans strains A8 and C54 and Klebsiella oxytoca strain M1. Mixed inoculum was prepared from indigenous communities of mycorrhizas in soils sampled from the Cerebos Salt Pan and the Kalahari Desert. Mycorrhizal diversity was investigated using 454-Pyrosequencing which revealed that the community composition was dominated by species in the Ambispora, Glomus and Paraglomus genera with a rare component represented by species in the Redeckera, Archaeospora and Geosiphon genera. Microscopic examination of plant roots at the end of the trial revealed the presence of diagnostic mycorrhizal structures within the root cells, confirming that colonization was successful. Plant growth response to microbial inoculation was assessed by monitoring changes in plant photosynthetic capacity over the duration of a 7 week pot trial. A significant difference in photosynthetic and biomass data was observed between drought and well-watered groups but no mycorrhizal or bacterial treatment effect was evident within the groups, despite the high levels of colonization by mycorrhizas. These results suggest that the beneficial effects of mycorrhizal colonization may be primarily attributed to improved nutrient and mineral uptake in conditions where nutrients are limiting, resulting in improved growth. The improved growth may then have secondary effects on the plant‟s ability to withstand drought. Having controlled for nutrient deficiency, it was not evident in this study that mycorrhizal fungi were able to stimulate a change in plant physiology and confer drought tolerance under the conditions imposed.
- Full Text:
- Date Issued: 2016
Investigation of α-aryl substituted 3-indolylethanones as potential antiplasmodial agents
- Authors: Svogie, Archibald Lesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/55487 , vital:26704
- Description: According to the World Health Organisation (WHO), deaths attributed to Plasmodium falciparum exceeded 584 000 in 2013, with 198 million new cases of malaria being reported. One contributing factor to these alarming figures is the emergence of drug resistance against available antimalarial agents. Therefore, there is a pressing need to develop new therapeutic antimalarial drugs with novel mechanisms of action in order to curb the increasing spread of malaria. The indole scaffold is often associated with biologically active compounds, recently exemplified by the antimalarial agent NITD609, which is currently in phase 1 clinical trials. Based on the biological evaluation of a small series of indolyl-3-amides and esters which showed moderate antimalarial activity, coupled to significant toxicity, we were prompted to investigate the synthesis of a series of indolyl-3-ethanone-α-amines (3.37 and 3.41), ethers (3.39 and 3.44) and thioethers (3.42, 3.43, 3.40, 3.45 – 3.73), where the carbonyl moiety and respective heteroatom were separated by a methine spacer. We further investigated these compounds for in vitro biological activity against P. falciparum and a human HeLa cell line. Our study explored the synthetic pathway of a three-step procedure toward our target compounds, with the initial Friedel-Crafts acetylation of indole, followed by α-bromination of the respective 3-acetylindoles. Finally, the halogen of the α-bromo ketone was substituted with an appropriate nucleophile, to yield our desired compounds. Various reagents were explored to optimise the nucleophilic displacement step, including potassium carbonate and various silver containing compounds. While many of the silver salts were found to assist in nucleophilic substitution, none were superior to the addition of potassium carbonate. The majority of compounds, chiefly the thioethers, displayed promising antimalarial activity, against the chloroquine sensitive 3D7 P. falciparum strain, with two thioethers in particular (3.54 and 3.65) inhibiting P. falciparum in the low nanomolar range. Additionally, active compounds were generally found to be non-toxic against HeLa cells, indicating that indolyl-3-thioethers are selective for the malaria parasite. These findings allowed us to begin hypothesising a structure activity relationship of this class, as well as elucidating the possible pharmacophore. In a speculative attempt to uncover the possible mechanism of action of these active compounds, in silico docking studies were conducted against Staphylococcus aureus HPPK (PDB ID: 4CRJ), which is an enzyme that immediately precedes DHPS in the microbial folate biosynthesis. Inhibition of folate biosynthesis is a validated selective antimalarial pathway and HPPK also exists in P. falciparum. Results from these docking studies suggested that our inhibitors bound well in the HPPK ATP pocket and were supportive of our hypothesized structure activity relationship.
- Full Text:
- Date Issued: 2016
- Authors: Svogie, Archibald Lesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/55487 , vital:26704
- Description: According to the World Health Organisation (WHO), deaths attributed to Plasmodium falciparum exceeded 584 000 in 2013, with 198 million new cases of malaria being reported. One contributing factor to these alarming figures is the emergence of drug resistance against available antimalarial agents. Therefore, there is a pressing need to develop new therapeutic antimalarial drugs with novel mechanisms of action in order to curb the increasing spread of malaria. The indole scaffold is often associated with biologically active compounds, recently exemplified by the antimalarial agent NITD609, which is currently in phase 1 clinical trials. Based on the biological evaluation of a small series of indolyl-3-amides and esters which showed moderate antimalarial activity, coupled to significant toxicity, we were prompted to investigate the synthesis of a series of indolyl-3-ethanone-α-amines (3.37 and 3.41), ethers (3.39 and 3.44) and thioethers (3.42, 3.43, 3.40, 3.45 – 3.73), where the carbonyl moiety and respective heteroatom were separated by a methine spacer. We further investigated these compounds for in vitro biological activity against P. falciparum and a human HeLa cell line. Our study explored the synthetic pathway of a three-step procedure toward our target compounds, with the initial Friedel-Crafts acetylation of indole, followed by α-bromination of the respective 3-acetylindoles. Finally, the halogen of the α-bromo ketone was substituted with an appropriate nucleophile, to yield our desired compounds. Various reagents were explored to optimise the nucleophilic displacement step, including potassium carbonate and various silver containing compounds. While many of the silver salts were found to assist in nucleophilic substitution, none were superior to the addition of potassium carbonate. The majority of compounds, chiefly the thioethers, displayed promising antimalarial activity, against the chloroquine sensitive 3D7 P. falciparum strain, with two thioethers in particular (3.54 and 3.65) inhibiting P. falciparum in the low nanomolar range. Additionally, active compounds were generally found to be non-toxic against HeLa cells, indicating that indolyl-3-thioethers are selective for the malaria parasite. These findings allowed us to begin hypothesising a structure activity relationship of this class, as well as elucidating the possible pharmacophore. In a speculative attempt to uncover the possible mechanism of action of these active compounds, in silico docking studies were conducted against Staphylococcus aureus HPPK (PDB ID: 4CRJ), which is an enzyme that immediately precedes DHPS in the microbial folate biosynthesis. Inhibition of folate biosynthesis is a validated selective antimalarial pathway and HPPK also exists in P. falciparum. Results from these docking studies suggested that our inhibitors bound well in the HPPK ATP pocket and were supportive of our hypothesized structure activity relationship.
- Full Text:
- Date Issued: 2016
Islamic compliant short term insurance: an exploratory study to develop an Islamic compliant insurance model within a South African context
- Authors: Jeeva, Shakir
- Date: 2016
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193633 , vital:45375
- Description: In a world where there is ever increasing risks to be mitigated, either by choice or due to the law of the country, an insurance instrument is the most popular risk mitigation tool. However, from an Islamic perspective, Muslims have certain parameters to adhere to due to the laws and boundaries as set out in the Quraan, as well as the teachings of the final prophet, Prophet Muhammed (Peace Be Upon Him). This has relevance in this context as, according to Islam, the conventional insurance models are in contravention of certain Islamic laws as they contain elements which are not acceptable in the Muslim faith. Therefore, the Islamic insurance models, or Takaful models, have removed the impermissible elements of usury, speculation, and uncertainty, which are all contained in the current conventional insurance models. By removing these impermissible elements from the insurance model, the Takaful model is acceptable for Muslims to use as a risk mitigation tool. The primary aim of the study sought to propose a short term Islamic compliant insurance model within a South African framework. The secondary aims were to ascertain the Islamic requirements for an Islamic insurance model, how these requirements fit into an insurance model, to then compare and contrast the differences between conventional insurance and Islamic insurance and, lastly, to explore awareness and attitudes towards Islamic insurance. Therefore, from the above, a proposed short term Islamic insurance model was developed within a South African context which conforms to the laws and boundaries of Islam, making this insurance model permissible to use as a Takaful tool. Additionally, semi structured interviews were conducted with certain research participants, using purposive sampling, to examine the attitudes and knowledge of the Muslim community towards the Takaful model within a South African context. It was concluded that while the majority of the research participants understand the Takaful model and the significance of this, they have chosen to use the conventional insurance offerings due to the fact that they were unaware of other Takaful alternatives, or due to the fact that the Takaful alternative was out-priced when compared to the conventional insurance offerings. It was therefore concluded that while there is a need for Takaful offerings within South Africa, this must be done in conjunction with additional marketing, education and competitive pricing for potential clients to consider this as an insurance option. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2016
- Full Text:
- Date Issued: 2016
- Authors: Jeeva, Shakir
- Date: 2016
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193633 , vital:45375
- Description: In a world where there is ever increasing risks to be mitigated, either by choice or due to the law of the country, an insurance instrument is the most popular risk mitigation tool. However, from an Islamic perspective, Muslims have certain parameters to adhere to due to the laws and boundaries as set out in the Quraan, as well as the teachings of the final prophet, Prophet Muhammed (Peace Be Upon Him). This has relevance in this context as, according to Islam, the conventional insurance models are in contravention of certain Islamic laws as they contain elements which are not acceptable in the Muslim faith. Therefore, the Islamic insurance models, or Takaful models, have removed the impermissible elements of usury, speculation, and uncertainty, which are all contained in the current conventional insurance models. By removing these impermissible elements from the insurance model, the Takaful model is acceptable for Muslims to use as a risk mitigation tool. The primary aim of the study sought to propose a short term Islamic compliant insurance model within a South African framework. The secondary aims were to ascertain the Islamic requirements for an Islamic insurance model, how these requirements fit into an insurance model, to then compare and contrast the differences between conventional insurance and Islamic insurance and, lastly, to explore awareness and attitudes towards Islamic insurance. Therefore, from the above, a proposed short term Islamic insurance model was developed within a South African context which conforms to the laws and boundaries of Islam, making this insurance model permissible to use as a Takaful tool. Additionally, semi structured interviews were conducted with certain research participants, using purposive sampling, to examine the attitudes and knowledge of the Muslim community towards the Takaful model within a South African context. It was concluded that while the majority of the research participants understand the Takaful model and the significance of this, they have chosen to use the conventional insurance offerings due to the fact that they were unaware of other Takaful alternatives, or due to the fact that the Takaful alternative was out-priced when compared to the conventional insurance offerings. It was therefore concluded that while there is a need for Takaful offerings within South Africa, this must be done in conjunction with additional marketing, education and competitive pricing for potential clients to consider this as an insurance option. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2016
- Full Text:
- Date Issued: 2016
Isolation, characterization and biomimetic oxidation of selected marine natural products and their analogues
- Authors: Mutsvairo, Tafadzwa
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64685 , vital:28592
- Description: Marine brown algae produce a variety of terpenes with a wide range of biological activities. However, very few phytochemical studies of brown algae have been conducted in South Africa. Therefore, in our continued search for biologically active natural products, we examined the South African brown alga Brassicophycus brassicaeformis. The dichloromethane-methanol extract of B.brassicaeformis was fractionated by silica gel column chromatography followed by normal phase HPLC to give pure four pure compounds which were identified by spectroscopic methods as; fucosterol, fucoxanthin and two monogalactosyldiacylglycerol lipids. Many potential drug molecules such as natural products have failed to reach the market due to poor pharmacokinetic and metabolic profiles despite having potent biological activity. Therefore the importance of early drug metabolism studies in the drug development process is clear. A biomimetic oxidation model was used for in vitro drug metabolism studies to predict any possible metabolites that could be produced by these natural products. Two biomimetic oxidation models catalyzed by two water soluble metalloporphyrins as biomimics of cytochrome P450, in the presence of two terminal oxidants either hydrogen peroxide or iodobenzene diacetete were successfully developed. The models were applied to a range of natural products. The oxidation of the quinone natural products, sargahydroquinoic acid, and lapachol was most easily achieved by metalloporphyrins employed in this study.
- Full Text:
- Date Issued: 2016
- Authors: Mutsvairo, Tafadzwa
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64685 , vital:28592
- Description: Marine brown algae produce a variety of terpenes with a wide range of biological activities. However, very few phytochemical studies of brown algae have been conducted in South Africa. Therefore, in our continued search for biologically active natural products, we examined the South African brown alga Brassicophycus brassicaeformis. The dichloromethane-methanol extract of B.brassicaeformis was fractionated by silica gel column chromatography followed by normal phase HPLC to give pure four pure compounds which were identified by spectroscopic methods as; fucosterol, fucoxanthin and two monogalactosyldiacylglycerol lipids. Many potential drug molecules such as natural products have failed to reach the market due to poor pharmacokinetic and metabolic profiles despite having potent biological activity. Therefore the importance of early drug metabolism studies in the drug development process is clear. A biomimetic oxidation model was used for in vitro drug metabolism studies to predict any possible metabolites that could be produced by these natural products. Two biomimetic oxidation models catalyzed by two water soluble metalloporphyrins as biomimics of cytochrome P450, in the presence of two terminal oxidants either hydrogen peroxide or iodobenzene diacetete were successfully developed. The models were applied to a range of natural products. The oxidation of the quinone natural products, sargahydroquinoic acid, and lapachol was most easily achieved by metalloporphyrins employed in this study.
- Full Text:
- Date Issued: 2016
Karoo dolerite intrusions: shaping the landscapes of the Great Karoo
- Authors: Marsh, Julian S
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/145111 , vital:38409 , ISBN 9781775845386 , https://books.google.co.za/books?id=YQ5bDwAAQBAJanddq=Karoo+dolerite+intrusions+JULIAN+MARSHandsource=gbs_navlinks_s
- Description: Karoo dolerite intrusions: shaping the landscapes of the Great Karoo.
- Full Text:
- Date Issued: 2016
- Authors: Marsh, Julian S
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/145111 , vital:38409 , ISBN 9781775845386 , https://books.google.co.za/books?id=YQ5bDwAAQBAJanddq=Karoo+dolerite+intrusions+JULIAN+MARSHandsource=gbs_navlinks_s
- Description: Karoo dolerite intrusions: shaping the landscapes of the Great Karoo.
- Full Text:
- Date Issued: 2016
Keeping it in the family: coevolution of latrunculid sponges and their dominant bacterial symbionts
- Matcher, Gwynneth F, Waterworth, Samantha C, Walmsley, Tara A, Matsatsa, Tendayi, Parker-Nance, Shirley, Davies-Coleman, Michael T, Dorrington, Rosemary A
- Authors: Matcher, Gwynneth F , Waterworth, Samantha C , Walmsley, Tara A , Matsatsa, Tendayi , Parker-Nance, Shirley , Davies-Coleman, Michael T , Dorrington, Rosemary A
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65603 , vital:28818 , https://doi.org/10.1002/mbo3.417
- Description: publisher version , The Latrunculiidae are a family of cold water sponges known for their production of bioactive pyrroloiminoquinone alkaloids. Previously it was shown that the bacterial community associated with a Tsitsikamma sponge species comprises unusual bacterial taxa and is dominated by a novel Betaproteobacterium. Here, we have characterized the bacterial communities associated with six latrunculid species representing three genera (Tsitsikamma, Cyclacanthia, and Latrunculia) as well as a Mycale species, collected from Algoa Bay on the South African southeast coast. The bacterial communities of all seven sponge species were dominated by a single Betaproteobacterium operational taxonomic unit (OTU0.03), while a second OTU0.03 was dominant in the Mycale sp. The Betaproteobacteria OTUs from the different latrunculid sponges are closely related and their phylogenetic relationship follows that of their hosts. We propose that the latrunculid Betaproteobacteria OTUs are members of a specialized group of sponge symbionts that may have coevolved with their hosts. A single dominant Spirochaetae OTU0.03 was present in the Tsitsikamma and Cyclacanthia sponge species, but absent from the Latrunculia and Mycale sponges. This study sheds new light on the interactions between latrunculid sponges and their bacterial communities and may point to the potential involvement of dominant symbionts in the biosynthesis of the bioactive secondary metabolites. , This research was supported by a SARChI grant from the South African National Research Foundation (NRF, GUN: 87583) and the Rhodes University Sandisa Imbewu Programme. S. C. W. was supported by an NRF Innovation PhD Scholarship and a Rhodes University Henderson PhD Scholarship. T. A. W. was supported by PhD Fellowships from the NRF and the German Academic Exchange Service (DAAD)
- Full Text:
- Date Issued: 2016
- Authors: Matcher, Gwynneth F , Waterworth, Samantha C , Walmsley, Tara A , Matsatsa, Tendayi , Parker-Nance, Shirley , Davies-Coleman, Michael T , Dorrington, Rosemary A
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65603 , vital:28818 , https://doi.org/10.1002/mbo3.417
- Description: publisher version , The Latrunculiidae are a family of cold water sponges known for their production of bioactive pyrroloiminoquinone alkaloids. Previously it was shown that the bacterial community associated with a Tsitsikamma sponge species comprises unusual bacterial taxa and is dominated by a novel Betaproteobacterium. Here, we have characterized the bacterial communities associated with six latrunculid species representing three genera (Tsitsikamma, Cyclacanthia, and Latrunculia) as well as a Mycale species, collected from Algoa Bay on the South African southeast coast. The bacterial communities of all seven sponge species were dominated by a single Betaproteobacterium operational taxonomic unit (OTU0.03), while a second OTU0.03 was dominant in the Mycale sp. The Betaproteobacteria OTUs from the different latrunculid sponges are closely related and their phylogenetic relationship follows that of their hosts. We propose that the latrunculid Betaproteobacteria OTUs are members of a specialized group of sponge symbionts that may have coevolved with their hosts. A single dominant Spirochaetae OTU0.03 was present in the Tsitsikamma and Cyclacanthia sponge species, but absent from the Latrunculia and Mycale sponges. This study sheds new light on the interactions between latrunculid sponges and their bacterial communities and may point to the potential involvement of dominant symbionts in the biosynthesis of the bioactive secondary metabolites. , This research was supported by a SARChI grant from the South African National Research Foundation (NRF, GUN: 87583) and the Rhodes University Sandisa Imbewu Programme. S. C. W. was supported by an NRF Innovation PhD Scholarship and a Rhodes University Henderson PhD Scholarship. T. A. W. was supported by PhD Fellowships from the NRF and the German Academic Exchange Service (DAAD)
- Full Text:
- Date Issued: 2016
Knowledge and knowers in teaching and learning: an enhanced approach to curriculum alignment
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59823 , vital:27655 , http://www.legitimationcodetheory.com/pdf/2016Clarence-c.pdf
- Description: John Biggs’ well-known curriculum design approach, constructive alignment, is widely used in higher education in the United Kingdom, Australia and South Africa. Developed with one dominant account of learning through curriculum, this approach has a gap in terms of accounting for other kinds of knowledge building, and associated knower development. This paper proposes a complementary approach that accounts for different kinds of knowledge and knower building. Using Legitimation Code Theory’s concept of Specialisation, the paper argues that accounting for what makes a discipline ‘special’ in terms of its basis for legitimate achievement can enable curriculum writers to align curricula more effectively with that basis in different disciplines. Using a case study approach, this paper shows how this tool can provide lecturers and academic development practitioners with a useful mode of analysing curriculum alignment to more ably account for differential development of disciplinary knowledges and knowers.
- Full Text:
- Date Issued: 2016
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59823 , vital:27655 , http://www.legitimationcodetheory.com/pdf/2016Clarence-c.pdf
- Description: John Biggs’ well-known curriculum design approach, constructive alignment, is widely used in higher education in the United Kingdom, Australia and South Africa. Developed with one dominant account of learning through curriculum, this approach has a gap in terms of accounting for other kinds of knowledge building, and associated knower development. This paper proposes a complementary approach that accounts for different kinds of knowledge and knower building. Using Legitimation Code Theory’s concept of Specialisation, the paper argues that accounting for what makes a discipline ‘special’ in terms of its basis for legitimate achievement can enable curriculum writers to align curricula more effectively with that basis in different disciplines. Using a case study approach, this paper shows how this tool can provide lecturers and academic development practitioners with a useful mode of analysing curriculum alignment to more ably account for differential development of disciplinary knowledges and knowers.
- Full Text:
- Date Issued: 2016
Knowledge structures and their relevance for teaching and learning in Introductory Financial Accounting
- Authors: Myers, Peta L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text
- Identifier: vital:21107 , http://hdl.handle.net/10962/6413 , http://dx.doi.org/10.1080/10291954.2015.1099215
- Description: The structure of knowledge within a discipline has implications for the teaching and learning within the discipline. This research examines how the hierarchical knowledge structure of Accounting impacts on the teaching and learning which takes place in a first semester Introductory Financial Accounting course. Students used on-line questionnaires and interviews to explain how they engaged with the discipline and difficulties which they experienced during the semester. Bernstein's pedagogic Device and Maton's Legitimation Code Theory were used to analyse the structure of knowledge within the discipline and as theoretical lenses through which to view these students' perceptions. The research provides a theoretical explanation for the impact that a hierarchical knowledge structure has on teaching and learning within the discipline; how students need to develop a 'trained gaze' and thereby gain mastery over the 'procedures of investigation' to be able to produce the 'legitimate text' required for success in the course. The research also explains why some students experience a 'code clash' and the implications this has for their success in the discipline. Other pedagogical difficulties which were experienced by these students, as a result of the hierarchical knowledge structure within the discipline, are also discussed. In addition to providing a better understanding of the phenomena that drive or hinder student learning, which could contribute towards improving pedagogy and hence student learning, theorising these concepts provides a common language to enable more informed debate on these issues.
- Full Text:
- Date Issued: 2016
- Authors: Myers, Peta L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text
- Identifier: vital:21107 , http://hdl.handle.net/10962/6413 , http://dx.doi.org/10.1080/10291954.2015.1099215
- Description: The structure of knowledge within a discipline has implications for the teaching and learning within the discipline. This research examines how the hierarchical knowledge structure of Accounting impacts on the teaching and learning which takes place in a first semester Introductory Financial Accounting course. Students used on-line questionnaires and interviews to explain how they engaged with the discipline and difficulties which they experienced during the semester. Bernstein's pedagogic Device and Maton's Legitimation Code Theory were used to analyse the structure of knowledge within the discipline and as theoretical lenses through which to view these students' perceptions. The research provides a theoretical explanation for the impact that a hierarchical knowledge structure has on teaching and learning within the discipline; how students need to develop a 'trained gaze' and thereby gain mastery over the 'procedures of investigation' to be able to produce the 'legitimate text' required for success in the course. The research also explains why some students experience a 'code clash' and the implications this has for their success in the discipline. Other pedagogical difficulties which were experienced by these students, as a result of the hierarchical knowledge structure within the discipline, are also discussed. In addition to providing a better understanding of the phenomena that drive or hinder student learning, which could contribute towards improving pedagogy and hence student learning, theorising these concepts provides a common language to enable more informed debate on these issues.
- Full Text:
- Date Issued: 2016
Knowledge, perceptions and willingness to control designated invasive tree species in urban household gardens in South Africa
- Shackleton, Charlie M, Shackleton, Ross T
- Authors: Shackleton, Charlie M , Shackleton, Ross T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180445 , vital:43389 , xlink:href="https://doi.org/10.1007/s10530-016-1104-7"
- Description: Many biological invasions result in negative impacts on the environment and human livelihoods, but simultaneously some also provide benefits that are valued differently by various stakeholders. To inform policy and management of invasive species it is important to assess landowners’ and broader society’s knowledge and perceptions of invasive species, something which is lacking in many contexts, especially in urban settings. In this study we interviewed 153 householders living in a medium-sized South African town who had declared invasive alien trees in their gardens. Less than half of the respondents could identify the invasive tree on their property and only one-third knew that it was an invasive alien species. There was a positive association between income and education levels with exposure to media about invasive alien species and respondents’ ability to identify the species and name any other invasive alien tree species. Knowledge levels were unequal across species. Amongst those who knew the tree was an invasive alien species, reasons why they retained it in their gardens included that it would be costly or too much effort to remove, they liked the tree, that it was not causing any harm and that the property was rented and so its removal was not their responsibility. However, the majority of people (83 %) were willing to have it removed from their garden if done for free by appropriate agencies, which is promising for compliance with new regulations on invasive species implemented at the end of 2014 in South Africa. The results also highlight the need for targeted and appropriate education and awareness programs amongst urban householders on invasive alien species, relevant legislation and their obligations.
- Full Text:
- Date Issued: 2016
- Authors: Shackleton, Charlie M , Shackleton, Ross T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180445 , vital:43389 , xlink:href="https://doi.org/10.1007/s10530-016-1104-7"
- Description: Many biological invasions result in negative impacts on the environment and human livelihoods, but simultaneously some also provide benefits that are valued differently by various stakeholders. To inform policy and management of invasive species it is important to assess landowners’ and broader society’s knowledge and perceptions of invasive species, something which is lacking in many contexts, especially in urban settings. In this study we interviewed 153 householders living in a medium-sized South African town who had declared invasive alien trees in their gardens. Less than half of the respondents could identify the invasive tree on their property and only one-third knew that it was an invasive alien species. There was a positive association between income and education levels with exposure to media about invasive alien species and respondents’ ability to identify the species and name any other invasive alien tree species. Knowledge levels were unequal across species. Amongst those who knew the tree was an invasive alien species, reasons why they retained it in their gardens included that it would be costly or too much effort to remove, they liked the tree, that it was not causing any harm and that the property was rented and so its removal was not their responsibility. However, the majority of people (83 %) were willing to have it removed from their garden if done for free by appropriate agencies, which is promising for compliance with new regulations on invasive species implemented at the end of 2014 in South Africa. The results also highlight the need for targeted and appropriate education and awareness programs amongst urban householders on invasive alien species, relevant legislation and their obligations.
- Full Text:
- Date Issued: 2016
Knowledge-building: educational studies in Legitimation Code Theory
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: book review , text
- Identifier: http://hdl.handle.net/10962/61300 , vital:28013 , http://dx.doi.org/10.1080/14703297.2016.1231751
- Description: A challenge facing higher education researchers, especially those new to the craft of research, is that of moving between theory and data effectively in order to mediate research findings clearly to readers. For postgraduate students and academics publishing their research, working with data and designing effective and fit-for-purpose methodologies can be a challenge. Moreover, this is not necessarily an easy area for supervisors and research mentors to assist with. In addition to researchers, practitioners working in academic development also need ways of using research – either empirical or conceptual – to augment their work with lecturers to improve teaching and learning. There are many handbooks that detail the differences between qualitative, quantitative and mixed-methods research. There are many theoretical texts to choose from. But there are few texts that offer researchers and those mentoring researchers insight into how methodology and theory connect in research studies, as well as practical tools to navigate the chaos of research, bringing theory and data into conversation in relevant and problem-oriented ways that can influence practice effectively. Karl Maton, in his introduction to this edited collection, argues that in spite of many claims within educational and social research for the need to connect research with theory more effectively, ‘the two frequently remain divorced or, at best, not on speaking terms’ (p. 1). The central premise of the book flows from this: we need to move beyond calls for more theory-informed research into education and society towards generating ways of demonstrating enactments of research that bring theory and research together meaningfully. The need for the research we publish to make clear its theoretical and methodological underpinning and enactments is crucial for effecting sustainable and meaningful change in practice within the field. This text, located within the growing field of Legitimation Code Theory (LCT) research, within the broader field of sociology of education, takes a generous step in that direction. Building on Maton’s 2014 text, Knowledge and knowers. Towards a realist sociology of education, this text delves into how LCT concepts – particularly in the dimensions of Specialisation and Semantics – can be enacted within educational research and practice.
- Full Text: false
- Date Issued: 2016
- Authors: Clarence, Sherran
- Date: 2016
- Language: English
- Type: book review , text
- Identifier: http://hdl.handle.net/10962/61300 , vital:28013 , http://dx.doi.org/10.1080/14703297.2016.1231751
- Description: A challenge facing higher education researchers, especially those new to the craft of research, is that of moving between theory and data effectively in order to mediate research findings clearly to readers. For postgraduate students and academics publishing their research, working with data and designing effective and fit-for-purpose methodologies can be a challenge. Moreover, this is not necessarily an easy area for supervisors and research mentors to assist with. In addition to researchers, practitioners working in academic development also need ways of using research – either empirical or conceptual – to augment their work with lecturers to improve teaching and learning. There are many handbooks that detail the differences between qualitative, quantitative and mixed-methods research. There are many theoretical texts to choose from. But there are few texts that offer researchers and those mentoring researchers insight into how methodology and theory connect in research studies, as well as practical tools to navigate the chaos of research, bringing theory and data into conversation in relevant and problem-oriented ways that can influence practice effectively. Karl Maton, in his introduction to this edited collection, argues that in spite of many claims within educational and social research for the need to connect research with theory more effectively, ‘the two frequently remain divorced or, at best, not on speaking terms’ (p. 1). The central premise of the book flows from this: we need to move beyond calls for more theory-informed research into education and society towards generating ways of demonstrating enactments of research that bring theory and research together meaningfully. The need for the research we publish to make clear its theoretical and methodological underpinning and enactments is crucial for effecting sustainable and meaningful change in practice within the field. This text, located within the growing field of Legitimation Code Theory (LCT) research, within the broader field of sociology of education, takes a generous step in that direction. Building on Maton’s 2014 text, Knowledge and knowers. Towards a realist sociology of education, this text delves into how LCT concepts – particularly in the dimensions of Specialisation and Semantics – can be enacted within educational research and practice.
- Full Text: false
- Date Issued: 2016
Land acquisition for and local livelihood implications of biofuel development in Zimbabwe
- Authors: Thondhlana, Gladman
- Date: 2016
- Subjects: Biomass energy -- Government policy -- Zimbabwe Biomass energy -- Economic aspects -- Zimbabwe Biomass energy -- Environmental aspects -- Zimbabwe
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/49940 , vital:25944
- Description: In recent years, proponents of 'green and clean fuel' have argued that the costs of overreliance on fossil fuels could be reduced through transition to biofuels such as bio-ethanol. Global biofuel discourses suggest that any transition to biofuel invariably results in significant benefits, including energy independence, job creation, development of agro-industrial centres at local level and high revenue generations for the state with minimum negative impacts on the environment. With many risks and costs associated with traditional 'dirty' fuels, it is likely that many countries, particularly African countries, will move towards the 'green and clean fuel' alternative. However, until recently research has arguably paid limited attention to the local livelihood impacts related to land acquisition for biofuel development or the policy frameworks required to maximise biofuel benefits. With regards to biofuel benefits, some recent studies suggest that the much bandied potential for greater tax revenue, lowered fuel costs and wealth distribution from biofuel production have all been perverted with relatively little payoff in wage labour opportunities in return (e.g. Richardson, 2010; Wilkinson and Herrera, 2010). Based on work done in Chisumbanje communal lands of Zimbabwe (Thondhlana, 2015), this policy brief highlights the local livelihood impacts of biofuel development and discusses policy implications of the findings. By highlighting the justifications of biofuel development at any cost by the state, the study sheds some light on the conflicts between state interests and local livelihood needs.
- Full Text:
- Date Issued: 2016
- Authors: Thondhlana, Gladman
- Date: 2016
- Subjects: Biomass energy -- Government policy -- Zimbabwe Biomass energy -- Economic aspects -- Zimbabwe Biomass energy -- Environmental aspects -- Zimbabwe
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/49940 , vital:25944
- Description: In recent years, proponents of 'green and clean fuel' have argued that the costs of overreliance on fossil fuels could be reduced through transition to biofuels such as bio-ethanol. Global biofuel discourses suggest that any transition to biofuel invariably results in significant benefits, including energy independence, job creation, development of agro-industrial centres at local level and high revenue generations for the state with minimum negative impacts on the environment. With many risks and costs associated with traditional 'dirty' fuels, it is likely that many countries, particularly African countries, will move towards the 'green and clean fuel' alternative. However, until recently research has arguably paid limited attention to the local livelihood impacts related to land acquisition for biofuel development or the policy frameworks required to maximise biofuel benefits. With regards to biofuel benefits, some recent studies suggest that the much bandied potential for greater tax revenue, lowered fuel costs and wealth distribution from biofuel production have all been perverted with relatively little payoff in wage labour opportunities in return (e.g. Richardson, 2010; Wilkinson and Herrera, 2010). Based on work done in Chisumbanje communal lands of Zimbabwe (Thondhlana, 2015), this policy brief highlights the local livelihood impacts of biofuel development and discusses policy implications of the findings. By highlighting the justifications of biofuel development at any cost by the state, the study sheds some light on the conflicts between state interests and local livelihood needs.
- Full Text:
- Date Issued: 2016
Latrunculid sponges, their microbial communities and secondary metabolites: connecting conserved bacterial symbionts to pyrroloiminoquinone production
- Dorrington, Rosemary A, Hilliar, Storm Hannah, Kalinski, Jarmo-Charles J, Krause, Rui W M, McPhail, Kerry L, Parker-Nance, Shirley, Wlalmsley, Tara A, Waterworth, Samantha C
- Authors: Dorrington, Rosemary A , Hilliar, Storm Hannah , Kalinski, Jarmo-Charles J , Krause, Rui W M , McPhail, Kerry L , Parker-Nance, Shirley , Wlalmsley, Tara A , Waterworth, Samantha C
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65915 , vital:28858 , https://doi.org/10.1055/s-0036-1596655
- Description: publisher version , The Latrunculiidae are cold water sponges known for their production of bioactive pyrroloiminoquinone alkaloids (e.g. makaluvamines, discorhabdins and tsitsikammamines). Since pyrroloiminoquinones have also been isolated from sponges belonging to other families, ascidians and microorganisms, the biosynthetic origin of these alkaloids in latrunculid sponges is likely microbial. This study focuses on the secondary metabolites produced by closely-related Tsitsikamma species and Cyclacanthia bellae, all latrunculid sponges endemic to Algoa Bay on the South African southeast coast. The sponges produced suites of related pyrroloiminoquinones, including tsitsikammine A and B, and discohabdin C and V, the combination and relative abundance of which is species-specific. Characterisation of the diversity of sponge-associated bacterial communities revealed the unprecedented conservation of two dominant bacterial species. The first, a Betaproteobacterium, is also found in other latrunculids and related sponge families, representing a novel clade of sponge endosymbionts that have co-evolved with their hosts. The second conserved bacterial symbiont is a spirochaete found only in Cyclacanthia and Tsitsikamma species that is likely to have been recruited from free-living spirochaetes in the environment. This study sheds new light on the interactions between latrunculid sponges, their dominant bacterial symbionts, and the potential involvement of these bacteria in pyrroloiminoquinone biosynthesis.
- Full Text: false
- Date Issued: 2016
- Authors: Dorrington, Rosemary A , Hilliar, Storm Hannah , Kalinski, Jarmo-Charles J , Krause, Rui W M , McPhail, Kerry L , Parker-Nance, Shirley , Wlalmsley, Tara A , Waterworth, Samantha C
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/65915 , vital:28858 , https://doi.org/10.1055/s-0036-1596655
- Description: publisher version , The Latrunculiidae are cold water sponges known for their production of bioactive pyrroloiminoquinone alkaloids (e.g. makaluvamines, discorhabdins and tsitsikammamines). Since pyrroloiminoquinones have also been isolated from sponges belonging to other families, ascidians and microorganisms, the biosynthetic origin of these alkaloids in latrunculid sponges is likely microbial. This study focuses on the secondary metabolites produced by closely-related Tsitsikamma species and Cyclacanthia bellae, all latrunculid sponges endemic to Algoa Bay on the South African southeast coast. The sponges produced suites of related pyrroloiminoquinones, including tsitsikammine A and B, and discohabdin C and V, the combination and relative abundance of which is species-specific. Characterisation of the diversity of sponge-associated bacterial communities revealed the unprecedented conservation of two dominant bacterial species. The first, a Betaproteobacterium, is also found in other latrunculids and related sponge families, representing a novel clade of sponge endosymbionts that have co-evolved with their hosts. The second conserved bacterial symbiont is a spirochaete found only in Cyclacanthia and Tsitsikamma species that is likely to have been recruited from free-living spirochaetes in the environment. This study sheds new light on the interactions between latrunculid sponges, their dominant bacterial symbionts, and the potential involvement of these bacteria in pyrroloiminoquinone biosynthesis.
- Full Text: false
- Date Issued: 2016
LCT and systemic functional linguistics: Enacting complimentary theories for explanatory power
- Maton, Karl, Martin, James R, Matruglio, Erika S
- Authors: Maton, Karl , Martin, James R , Matruglio, Erika S
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/66491 , vital:28955
- Description: publisher version , Interdisciplinarity is the future. Such is the thrust of pronouncements repeatedly heard across the social sciences and humanities. Interdisciplinarity is often equated with intellectually and socially progressive stances and greater responsiveness to business and workplace needs. Yet such axiological and economic benefits are more often assumed or proclaimed than evidenced or demonstrated (Moore 2011). Moreover,what is declared to be 'interdisciplinary' often comprises the appropriation by literary or philosophical discourses of ideas from other fields rather than genuinely interdisciplinary dialogue. Nonetheless,to highlight the vacuity of much written in its name is not to dismiss the potential of interdisciplinarity itself. There are serious ontological and epistemological arguments for bringing disciplines together in substantive research (Bhaskar and Danermark 2006). Simply put,the social world comprises more than the phenomena addressed by any one discipline. Education,for example,involves at least knowledges, knowers, knowing, and the known, implicating insights from, among others,sociology,linguistics,psychology,and philosophy (Maton 2014b: 212-13). This is not to suggest a single study must encompass the disciplinary map in order to recreate reality in its entirety, Rather,it highlights that drawing on more than one disciplinary approach may offer greater explanatory power when exploring a specific problem-situation.
- Full Text: false
- Date Issued: 2016
- Authors: Maton, Karl , Martin, James R , Matruglio, Erika S
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/66491 , vital:28955
- Description: publisher version , Interdisciplinarity is the future. Such is the thrust of pronouncements repeatedly heard across the social sciences and humanities. Interdisciplinarity is often equated with intellectually and socially progressive stances and greater responsiveness to business and workplace needs. Yet such axiological and economic benefits are more often assumed or proclaimed than evidenced or demonstrated (Moore 2011). Moreover,what is declared to be 'interdisciplinary' often comprises the appropriation by literary or philosophical discourses of ideas from other fields rather than genuinely interdisciplinary dialogue. Nonetheless,to highlight the vacuity of much written in its name is not to dismiss the potential of interdisciplinarity itself. There are serious ontological and epistemological arguments for bringing disciplines together in substantive research (Bhaskar and Danermark 2006). Simply put,the social world comprises more than the phenomena addressed by any one discipline. Education,for example,involves at least knowledges, knowers, knowing, and the known, implicating insights from, among others,sociology,linguistics,psychology,and philosophy (Maton 2014b: 212-13). This is not to suggest a single study must encompass the disciplinary map in order to recreate reality in its entirety, Rather,it highlights that drawing on more than one disciplinary approach may offer greater explanatory power when exploring a specific problem-situation.
- Full Text: false
- Date Issued: 2016
LCT in mixed-methods research: evolving an instrument for quantitative data
- Maton, Karl, Howard, Sarah Katherine
- Authors: Maton, Karl , Howard, Sarah Katherine
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/66479 , vital:28954
- Description: publisher version , A mantra of social science declares a fundamental divide between the quantitative and the qualitative that involves more than methods. According to this depiction, the two methodologies are intrinsically associated with a range of ontological, epistemological, political and moral stances. Each of these constellations of stances is strongly integrated, such that choice of method is held to involve a series of associated choices. Each constellation is also strongly opposed to the other, along axes labelled positivism/constructivism, scientism/humanism, conservative/critical, old/new, among others. These ‘binary constellations’ (Maton 2014b: 148-70) offer a forced choice between two tightly-knit sets of practices that are portrayed as jointly exhaustive and mutually exclusive. So widespread is this methodological binarism that many scholars ‘are left with the impression that they have to pledge allegiance to one research school of thought or the other’ (Johnson and Onwuegbuzie 2004: 14). A competing mantra disclaims this divide. Distinctions underpinning the picture of binary constellations have been regularly dissolved. Arguments that one deals with numbers, the other with words, one studies behaviour, the other reveals meanings, one is hypothetico-deductive, the other inductive, one enables generalization, the other explores singular depth, among others, have been repeatedly undermined (e.g. Hammersley 1992). Indeed, the death of the divide is frequently declared. Calls for ‘transcending’ (Salomon 1991) or ‘getting over’ (Howe 1992) the quantitative-qualitative debate and arguments for mixed-methods research (Brannen 2005; Johnson and Onwuegbuzie 2004) are recurrent. These calls highlight how the methodologies offer complementary insights for research and demonstrate that eschewing either methodology on principle is unnecessarily renouncing potential explanatory power. However, the call to mixed-methods research remains more breached than honoured. Methodological monotheism remains dominant – studies of education and society typically adopt either quantitative or qualitative methods. As we shall discuss, the former is typically associated with the influence of psychology and the latter is often claimed as emblematic of sociology. Studies utilizing the sociological frameworks on which Legitimation Code Theory (LCT) builds have echoed this pattern by overwhelmingly adopting qualitative methods. Accordingly, Part I of this volume begins by exploring how LCT concepts can be enacted in qualitative research (Chapter 2). However, LCT is not limited to one methodology and a growing body of mixed-methods research is engaging with both qualitative and quantitative data. In this chapter we illustrate how this research works and the gains it offers. For resolutely qualitative researchers, the prospect of reading anything quantitative, even in mixed-methods research, may be unenticing. However, it would be a mistake to pass over this chapter, for several reasons. First, we offer insights into research practice that might surprise such scholars. As Bourdieu argued, ‘methodological indictments are too often no more than a disguised way of making a virtue out of necessity, of feigning to dismiss, to ignore in an active way, what one is ignorant of in fact’ (Bourdieu and Wacquant 1992: 226). Our aim is to contribute towards removing this reason for one-sidedness. We show, for example, how quantitative methods confound their common portrayal as neat, straightforward and procedural; they are complex and involved and require craft work and judgement. Our focus is, therefore, more practical than metaphysical. We shall not enter seemingly endless debates over whether the ‘quantitative-qualitative divide’ refers to paradigms, epistemologies or methods and whether these are complementary or incommensurable. Rather, we discuss the development of an instrument for enacting LCT concepts in quantitative methods and ground this account in real examples of mixed-methods research. Specifically, we trace the evolution of an instrument for embedding specialization codes within questionnaires through its creation for research into school music and then its development within studies of educational technology. Given that mathematics can be off-putting to the noviciate, we minimize discussion of statistics and explain measures in lay terms. Second, this is much more than a story of quantitative methods. The evolution of the instrument both shaped qualitative methods and was shaped by the data they generated, offering insights into how qualitative research can more fully engage with LCT. Its development also involved intimate dialogue with theory that shed fresh light on LCT itself, making explicit the ‘gaze’ embodied by the framework (Chapter 1, this volume). We shall highlight wider lessons learned about the craft of enacting LCT in research, lessons of direct relevance for studies using any methods. Third, we shall illustrate the explanatory power offered by using quantitative and qualitative methods together, such as providing a robust basis for detailed findings, identifying wider-scale trends typically inaccessible to qualitative methods that provide a context for their data, and facilitating knowledge-building through greater replicability across contexts and over time. For example, the technology studies built directly on the music studies to cumulatively develop the instrument and generated probably the largest data set in code sociology: 97,386 responses (83,937 student and 13,449 staff surveys) on the organizing principles of academic subjects, alongside 20 in-depth qualitative case studies of secondary schools. This offers a foundation of substantial breadth and depth for making claims about knowledge practices across the disciplinary map and a firm basis on which future research into disciplinary differences can build. Moreover, the quantitative instrument itself can be adopted or adapted in new studies, further enabling cumulative knowledge-building. Given these substantive, methodological and theoretical gains, it is perhaps surprising there exists any temptation to skip past discussion of mixed-methods research. This reflects the methodological character of the fields in which LCT emerged. We thus begin by briefly illustrating how the sociological frameworks on which the theory builds have become distanced from quantitative methods.
- Full Text: false
- Date Issued: 2016
- Authors: Maton, Karl , Howard, Sarah Katherine
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/66479 , vital:28954
- Description: publisher version , A mantra of social science declares a fundamental divide between the quantitative and the qualitative that involves more than methods. According to this depiction, the two methodologies are intrinsically associated with a range of ontological, epistemological, political and moral stances. Each of these constellations of stances is strongly integrated, such that choice of method is held to involve a series of associated choices. Each constellation is also strongly opposed to the other, along axes labelled positivism/constructivism, scientism/humanism, conservative/critical, old/new, among others. These ‘binary constellations’ (Maton 2014b: 148-70) offer a forced choice between two tightly-knit sets of practices that are portrayed as jointly exhaustive and mutually exclusive. So widespread is this methodological binarism that many scholars ‘are left with the impression that they have to pledge allegiance to one research school of thought or the other’ (Johnson and Onwuegbuzie 2004: 14). A competing mantra disclaims this divide. Distinctions underpinning the picture of binary constellations have been regularly dissolved. Arguments that one deals with numbers, the other with words, one studies behaviour, the other reveals meanings, one is hypothetico-deductive, the other inductive, one enables generalization, the other explores singular depth, among others, have been repeatedly undermined (e.g. Hammersley 1992). Indeed, the death of the divide is frequently declared. Calls for ‘transcending’ (Salomon 1991) or ‘getting over’ (Howe 1992) the quantitative-qualitative debate and arguments for mixed-methods research (Brannen 2005; Johnson and Onwuegbuzie 2004) are recurrent. These calls highlight how the methodologies offer complementary insights for research and demonstrate that eschewing either methodology on principle is unnecessarily renouncing potential explanatory power. However, the call to mixed-methods research remains more breached than honoured. Methodological monotheism remains dominant – studies of education and society typically adopt either quantitative or qualitative methods. As we shall discuss, the former is typically associated with the influence of psychology and the latter is often claimed as emblematic of sociology. Studies utilizing the sociological frameworks on which Legitimation Code Theory (LCT) builds have echoed this pattern by overwhelmingly adopting qualitative methods. Accordingly, Part I of this volume begins by exploring how LCT concepts can be enacted in qualitative research (Chapter 2). However, LCT is not limited to one methodology and a growing body of mixed-methods research is engaging with both qualitative and quantitative data. In this chapter we illustrate how this research works and the gains it offers. For resolutely qualitative researchers, the prospect of reading anything quantitative, even in mixed-methods research, may be unenticing. However, it would be a mistake to pass over this chapter, for several reasons. First, we offer insights into research practice that might surprise such scholars. As Bourdieu argued, ‘methodological indictments are too often no more than a disguised way of making a virtue out of necessity, of feigning to dismiss, to ignore in an active way, what one is ignorant of in fact’ (Bourdieu and Wacquant 1992: 226). Our aim is to contribute towards removing this reason for one-sidedness. We show, for example, how quantitative methods confound their common portrayal as neat, straightforward and procedural; they are complex and involved and require craft work and judgement. Our focus is, therefore, more practical than metaphysical. We shall not enter seemingly endless debates over whether the ‘quantitative-qualitative divide’ refers to paradigms, epistemologies or methods and whether these are complementary or incommensurable. Rather, we discuss the development of an instrument for enacting LCT concepts in quantitative methods and ground this account in real examples of mixed-methods research. Specifically, we trace the evolution of an instrument for embedding specialization codes within questionnaires through its creation for research into school music and then its development within studies of educational technology. Given that mathematics can be off-putting to the noviciate, we minimize discussion of statistics and explain measures in lay terms. Second, this is much more than a story of quantitative methods. The evolution of the instrument both shaped qualitative methods and was shaped by the data they generated, offering insights into how qualitative research can more fully engage with LCT. Its development also involved intimate dialogue with theory that shed fresh light on LCT itself, making explicit the ‘gaze’ embodied by the framework (Chapter 1, this volume). We shall highlight wider lessons learned about the craft of enacting LCT in research, lessons of direct relevance for studies using any methods. Third, we shall illustrate the explanatory power offered by using quantitative and qualitative methods together, such as providing a robust basis for detailed findings, identifying wider-scale trends typically inaccessible to qualitative methods that provide a context for their data, and facilitating knowledge-building through greater replicability across contexts and over time. For example, the technology studies built directly on the music studies to cumulatively develop the instrument and generated probably the largest data set in code sociology: 97,386 responses (83,937 student and 13,449 staff surveys) on the organizing principles of academic subjects, alongside 20 in-depth qualitative case studies of secondary schools. This offers a foundation of substantial breadth and depth for making claims about knowledge practices across the disciplinary map and a firm basis on which future research into disciplinary differences can build. Moreover, the quantitative instrument itself can be adopted or adapted in new studies, further enabling cumulative knowledge-building. Given these substantive, methodological and theoretical gains, it is perhaps surprising there exists any temptation to skip past discussion of mixed-methods research. This reflects the methodological character of the fields in which LCT emerged. We thus begin by briefly illustrating how the sociological frameworks on which the theory builds have become distanced from quantitative methods.
- Full Text: false
- Date Issued: 2016
Learning style of Chinese event management students
- Louw, Mattheus J, Louw, Lynette, Li, Yanxia
- Authors: Louw, Mattheus J , Louw, Lynette , Li, Yanxia
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69167 , vital:29438 , https://doi.org/10.1515/9783110366778-028
- Description: There is a demand for social development in China by establishing, inter alia, a framework focusing on the employability of university graduates and developing self-directed learners. The key to achieving this would be to gain a better understanding of how learning styles, as one of the cognitive factors, contribute towards academic performance in order to provide meaningful learning experiences.
- Full Text: false
- Date Issued: 2016
- Authors: Louw, Mattheus J , Louw, Lynette , Li, Yanxia
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69167 , vital:29438 , https://doi.org/10.1515/9783110366778-028
- Description: There is a demand for social development in China by establishing, inter alia, a framework focusing on the employability of university graduates and developing self-directed learners. The key to achieving this would be to gain a better understanding of how learning styles, as one of the cognitive factors, contribute towards academic performance in order to provide meaningful learning experiences.
- Full Text: false
- Date Issued: 2016
Legal ethics education in South Africa: possibilities, challenges and opportunities
- Robertson, Michael, Kruuse, Helen
- Authors: Robertson, Michael , Kruuse, Helen
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68941 , vital:29341 , http://dx.doi.org/10.1080/02587203.2016.1210934
- Description: Publisher version , The South African legal profession has been subject to harsh criticism in the last few years, leading to what some have called ‘an ethical crisis.’ Although this perception may or may not be warranted, there have been numerous calls for improved ethical legal practices by South African lawyers. This article seeks to contribute to a discussion about the importance of implementing legal ethics education in South African law schools. The authors (a) explore the meaning of ‘ethical legal practice’ by reference to the international literature; (b) examine the way in which legal ethics has so far been presented in the limited South African literature on the topic; (c) argue the need for a more thorough and critical literature on South African lawyers’ ethics, coupled with a commitment to developing a stronger legal ethics culture within the profession and the legal academia; and (d) suggest a possible approach for South African legal ethics education in the future, with reference to recent developments in other countries.
- Full Text: false
- Date Issued: 2016
- Authors: Robertson, Michael , Kruuse, Helen
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68941 , vital:29341 , http://dx.doi.org/10.1080/02587203.2016.1210934
- Description: Publisher version , The South African legal profession has been subject to harsh criticism in the last few years, leading to what some have called ‘an ethical crisis.’ Although this perception may or may not be warranted, there have been numerous calls for improved ethical legal practices by South African lawyers. This article seeks to contribute to a discussion about the importance of implementing legal ethics education in South African law schools. The authors (a) explore the meaning of ‘ethical legal practice’ by reference to the international literature; (b) examine the way in which legal ethics has so far been presented in the limited South African literature on the topic; (c) argue the need for a more thorough and critical literature on South African lawyers’ ethics, coupled with a commitment to developing a stronger legal ethics culture within the profession and the legal academia; and (d) suggest a possible approach for South African legal ethics education in the future, with reference to recent developments in other countries.
- Full Text: false
- Date Issued: 2016
Linking the ‘know-that’ and ‘know-how’ knowledge through games: a quest to evolve the future for science and engineering education
- Vahed, Anisa, McKenna, Sioux, Singh, S
- Authors: Vahed, Anisa , McKenna, Sioux , Singh, S
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66785 , vital:28993 , ISSN 1573-174X , https://doi.org/10.1007/s10734-015-9956-9
- Description: Publisher version , This paper responds to Muller’s notions of ‘knowing-that’ and ‘knowing how’. The paper addresses how educational interventions that are designed in line with targeted discipline-specific subjects can enhance the balance between professional practice and disciplinary knowledge in professionally accredited programmes at universities of technology. The context is a Dental Technology programme at a University of Technology in South Africa. Teaching through discipline-specific games, conceptualised from a game literacies perspective, is proposed as an engaging, interactive pedagogy for learning disciplinary knowledge that potentially encourages access to a particular affinity group. The authors use concepts from Bernstein and Maton to investigate whether epistemic relations or social relations are emphasised through board and digital games designed for two Dental Technology subjects. This paper offers valuable insight into alternative pedagogies that can be adopted into science, technology, engineering, and mathematics education with the aim of paving a pathway towards Muller’s Scenario 3.
- Full Text: false
- Date Issued: 2016
- Authors: Vahed, Anisa , McKenna, Sioux , Singh, S
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66785 , vital:28993 , ISSN 1573-174X , https://doi.org/10.1007/s10734-015-9956-9
- Description: Publisher version , This paper responds to Muller’s notions of ‘knowing-that’ and ‘knowing how’. The paper addresses how educational interventions that are designed in line with targeted discipline-specific subjects can enhance the balance between professional practice and disciplinary knowledge in professionally accredited programmes at universities of technology. The context is a Dental Technology programme at a University of Technology in South Africa. Teaching through discipline-specific games, conceptualised from a game literacies perspective, is proposed as an engaging, interactive pedagogy for learning disciplinary knowledge that potentially encourages access to a particular affinity group. The authors use concepts from Bernstein and Maton to investigate whether epistemic relations or social relations are emphasised through board and digital games designed for two Dental Technology subjects. This paper offers valuable insight into alternative pedagogies that can be adopted into science, technology, engineering, and mathematics education with the aim of paving a pathway towards Muller’s Scenario 3.
- Full Text: false
- Date Issued: 2016