An in silico analysis, purification and partial kinetic characterisation of a serine protease from Gelidium pristoides
- Authors: Ntsata, Zolani
- Date: 2020
- Subjects: Gelidium Proteolytic enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12076 , vital:39149
- Description: The aim of this study was to characterize the protease enzyme (s) from red algae. An in silico analysis of red algae genomes was used to identify gene coding for protease. Protease sequences identified from these genomes were examined for conserved domains, active site and structures. The domain search revealed that the identified sequences were from the five classes of protease enzymes. For function inference, the red algae sequences were aligned to identify the catalytic sites, and the tertiary structures were predicted using homology modelling. An in silico analysis provides an indication of the class and potential functions of the enzymes. However, it cannot predict whether the gene is constitutively expressed in the red algae or under which conditions it may be induced, and it cannot determine the kinetic efficiency of an enzyme against various substrate, or the optimum conditions for the protein activity. Attempts to clone and recombinantly express selected red algae proteases, proved unsuccessful, as the available genomes where from red algae species found mainly in Asia, and the designed primers, therefore, did not amplify a corresponding PCR product from the red algae harvested in South Africa. Crude extracts of red algae collected from Kenton-on-Sea, along the East Coast of South Africa, were screened for protease activity using Benzoyl-Arginine-pNitroAnilide (BApNA) as substrate. The proteases detected in the crude extract were purified using ammonium sulphate precipitation and HiPrep DEAE FF 16/10; CM FF 16/10, and HiPrep Q FF 16/10 columns for ion-exchange chromatography. The HiPrep Q FF 16/10 column yielded active protein, which revealed two bands of 11kDa and 17kDa on SDS-PAGE. It was assumed that these bands represented two subunits of the purified protease. Kinetic characterisation of the purified protease revealed a pH optimum of 9, using BApNA as substrate, a temperature optimum at 60ºC, and sensitivity to temperature when stored above 4ºC. The protease activity was inhibited by Ferric chloride (32%), induced by calcium chloride (156%), no inhibition by magnesium chloride (97%) and slight inhibition by potassium chloride (77%) and manganese chloride (70%). Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, almost totally inhibited the protease activity, indicating that the protease from red algae was most likely a serine protease. The Km and kcat values were 1.96 µM, and 0.364 s -1 , respectively using BApNA as the substrate. This study revealed that the red algae genome contains numerous genes that encode for proteases from almost all the classes of proteases. A serine protease from the red algae Gelidium pristoides was partially purified and kinetically characterised, confirming that red algae found along the Eastern Coast of South Africa contain genes that express active proteases that may be of medical or industrial interest. Further studies, however, are required to recombinantly express, purify and characterise the numerous proteases encoded by the genes identified in the in silico analysis of this study.
- Full Text:
- Date Issued: 2020
An initial investigation into biological control options for Schinus terebinthifolia in South Africa
- Authors: Magengelele, Nwabisa Laurencia
- Date: 2020
- Subjects: Anacardiaceae -- Biological control -- South Africa , Plants, Ornamental -- South Africa , Invasive plants -- Biological control -- South Africa , Insects as biological pest control agents -- South Africa , Brazilian pepper tree -- Biological control -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/103835 , vital:32306
- Description: Schinus terebinthifolia Raddi (Anacardiaceae) (Brazilian pepper tree) is a native tree to subtropical South America that was introduced into South Africa as an ornamental plant. Globally, it is regarded as one of the world’s worst invasive trees. In South Africa, this aggressive pioneer species is becoming increasingly problematic and is being considered as a target for biological control. In South Africa the tree has acquired a native seed-feeding wasp, Megastigmus transvaalensis Hussey (Hymenoptera: Torymidae). The wasp’s native hosts are indigenous Rhus species (Anacardiaceae), but it has expanded its host range to form a new association with both S. terebinthifolia and its close relative S. molle L. (Anacardiaceae). In order to quantify the seed predation by M. transvaalensis on S. terebinthifolia seeds, tree populations were surveyed across the Eastern Cape and KwaZulu-Natal provinces. The wasp was present at 99% of the S. terebinthifolia populations with an average of 22% of the seeds being destroyed. In the Eastern Cape Province, the highest seed damage occurred at the start of the winter months, when about 35% of seeds were damaged. This fell to less than 12% in spring and summer when the plants were flowering. Megastigmus transvaalensis may have slowed the rate of spread of the plant, but it is unlikely to reduce population sizes of S. terebinthifolia in South Africa in the long-term. Biological control efforts can be assisted by knowing the origin and invasion history of the target species. Genetic analyses are often the only way to elucidate the invasion history of invasive alien plants because it is rare to find detailed records of plant introductions. Both microsatellite and chloroplast DNA analysis were conducted on S. terebinthifolia trees from the plant’s introduced distribution in South Africa and both Florida and Hawaii, USA. These samples were compared to plants from the native distribution of South America. The analysis indicated that the S. terebinthifolia in South Africa was most likely sourced from the state of Rio de Janeiro in Brazil, which is the same source of the invasive populations in Florida and Hawaii. Importantly, the South African populations were all found to be “haplotype A”. Plants samples collected from Hawaii USA were the closest match to the South African plants. Biological control agents known to damage haplotype A which have been considered for use in Hawaii and Florida should therefore be prioritised for South Africa. Schinus terebinthifolia has a broad distribution in South Africa; however, the majority of the current distribution is limited to the coastal regions along the eastern coast in KwaZulu-Natal Province. This suggests that the species may be climatically limited. Species distribution models in MaxEnt were used to predict the suitable ecological niche of the species. Using occurrence localities from both the native and invaded range to calibrate the models resulted in 56% of the modelled areas being considered suitable for the growth of S. terebinthifolia in South Africa. This included areas in the Eastern Cape, Western Cape and Limpopo provinces. When the models were calibrated using just the native range data, or just the invaded range data, predicted distributions were more restricted and limited to the coastal areas of the Eastern Cape and KwaZulu-Natal provinces. The coastal areas between Florianopolis and Santos in Brazil were highlighted as the most climatically similar to the invasive populations of S. terebinthifolia in South Africa. These areas should be prioritised if native range surveys for potential biological control agents are conducted in South America. Although the native seed-feeding wasp is damaging to S. terebinthifolia in South Africa, the tree is still not under suitable levels of biological control and is likely to spread and increase in density. New biological control agents are therefore required. Genetic and climatic matching has determined where the most appropriate region to collect new potential biological control agents is. The genetic matching data has also indicated that biological control agents that have been released, or are being considered for release, in Hawaii and Florida, are likely to be suitable for the South African plants because they have been shown to be damaging to ‘haplotype A’. These agents should therefore be the first to be considered for release in South Africa.
- Full Text:
- Date Issued: 2020
An inquiry on the efficacy of structures by South African government to promote intergration of traditional medicine and modern medicine: A case of Mossel Bay, Western Cape Province
- Authors: Heynes, Derick Vincent
- Date: 2020
- Subjects: Traditional medicine -- South Africa -- Western cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46890 , vital:39723
- Description: The two health systems are currently functioning parallel to one another as it seeks to contribute towards improving the health care delivery systems in South Africa. The myriad of literature available on the topic has nudged this phenomenon into the spotlight, and this realisation became even more apparent since South Africa’s transition from a system of separate development (also known as apartheid) to a democratic dispensation in 1994. Traditional Medicine, also known as folk medicine or complementary and Alternative Medicine (also known as CAM), is regarded as the oldest form of health care system that has been around since the dawn of time. It is in ancient cultures that method of healing have used to cope and deal with various diseases that have threatened their existence and survival (Abdullahi, 2011). Botha (2004) puts it succinctly as she notes that the clash between traditional methods of healing and Western medical science in places like South Africa requires that we ask questions like “What is health?” “What does healing mean?” and outlines that the contemporary move towards the recognition of alternative medicine is concurrent with a shift in Western thinking on the nature of science, healing and human being. These concepts namely; “What is health?” and “What does healing mean?” will be expounded in the chapters that follow. The researcher concurs with Botha (2004) views in that access to basic health services, as well as related infrastructure, such as water supplies, sanitary works and roads, generally remains one of the biggest problems on the continent and this has a huge impact on health care delivery systems, particularly in South Africa.
- Full Text:
- Date Issued: 2020
An internal audit expectation gap: South African Revenue Services project audit engagements
- Authors: Sekhwela, Mmanapo Bella
- Date: 2020
- Subjects: Electronic data processing -- Auditing , Business enterprises -- Computer networks -- Security measures Information technology -- Security measures Computer security
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/47139 , vital:39815
- Description: South African Revenue Services (SARS) was established as a quasi-government organisation with a mandate to efficiently and effectively collect revenue based on the export, import, movement, manufacture and storage of specific goods. Information Technology (IT) governance is strategically important to SARS in that its business processes are technology driven and that technology projects are implemented to support the SARS strategic objectives. In alignment to the King code for corporate governance and ethical business practices, an Internal Audit Function (IAF) as a regulatory requirement of all public sector entities in South Africa exists at SARS. The aim of the research was to evaluate the perspectives of SARS stakeholders regarding the organisation’s IT project auditing process. The study focused on gathering data from various SARS stakeholders involved in the delivery of IT projects and IT projects auditing. Through a qualitative research approach, interviews were conducted with practitioners such as Internal Auditors, Internal Audit managers, and executives as well as project managers and ownersso asto obtain a holistic understanding of stakeholder expectations of an IT project audit. An analysis of the data collected led to the deduction of recommendations meant to enhance stakeholder perceptions of the IT audit function within SARS. The study found that there is a perceived value derived from IA reviews of IT projects. The findings also revealed that rather than lack of resources and expertise, skill set deficiencies were the major setback in achieving IA goals. The findings further revealed that there are deficiencies in the quality of IA reports. Some of the main recommendations were to expand the scope of the Internal Audit roles, intensify engagements of Internal Audits by the Enterprise Project Management Office (EPMO), improve the quality of reports, and capacitate Internal Auditors with reporting skills. This study presents a modest contribution that is expected to enrich knowledge on how to audit IT projects. Moreover, the study contributes towards a methodological position of design science by producing results from a smaller sample augmented by interview results in an environment characterised by smaller populations so that inferences can be made.
- Full Text:
- Date Issued: 2020
An investigation into the emergence of teacher leadership: a case study at an urban state senior secondary school in the Oshana Region, Namibia
- Authors: Nakafingo, Saara Lovisa
- Date: 2020
- Subjects: Educational leadership -- Namibia , Action research in education -- Namibia , Active learning -- Namibia , Continuing education -- Namibia , School management and organization -- Namibia , Cultural Historical Activity Theory
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144645 , vital:38365
- Description: Promoting a collaborative culture and collective leadership in school has the potential to improve school performance. This may be realised through, among others, the development of teacher leadership. Teacher leadership can be referred to as the opportunities that teachers have to exercise leadership in their schools. Teacher leadership has a potential as a mechanism to bring about change in schools (Grant, 2012). Nevertheless, the concept of teacher leadership seems to be a dream, as little or no attention is being given to the phenomenon. The literature on leadership focuses mostly on those in formal leadership positions. This study thus aims to critically investigate the emergence of teacher leadership (a more informal leadership) in a case study school in order to create opportunities for teacher leadership development. As a qualitative case study adopting a formative interventionist approach, the study engaged teachers and SMT members using questionnaires, interviews and observation as data generating tools for a deeper understanding of the concept. Additionally, some documents in the school were analysed for the purpose of crystallisation. The study was guided by five research questions namely: How is the concept teacher leadership understood by teachers and SMT members in the school? What leadership roles do teachers currently fulfil in their school? What are the cultural-historical factors that enable or constrain teacher leadership in a school? How can a series of change laboratory workshops develop teacher leadership in a school? How did the change laboratory workshop sessions benefit the participants? Data was analysed adopting the teacher leadership model as a framework (Grant, 2017b) and the lens of Cultural Historical Activity Theory was also utilised in the analysis which enabled the participants to surface the systemic causes of challenges in the development of teacher leadership. The findings revealed that teachers and SMT members had an understanding of the concept teacher leadership, but their perceptions were different. Furthermore, evidence of teacher leadership existed across the various zones when teacher leaders fulfilled different roles; however, it was evident that teachers led more at the classroom level. Additionally, the study also found that certain factors enabled the practice of teacher leadership. However, it also emerged that challenges constrained the development of teacher leadership in the case study school. Some of these challenges included: the notion of top-down school management structure, time constraints and demanding teacher workloads, limited leadership knowledge, and teachers’ lack of courage and motivation to lead. For this reason, four change laboratory workshops were conducted and findings suggested that the establishment of a Teachers’ Continuous Professional Development club as a transformative agency for teacher leadership development was necessary.
- Full Text:
- Date Issued: 2020
An investigation into the fire regimes of the upper Tsitsa River catchment
- Authors: Snyman, Gareth
- Date: 2020
- Subjects: Prescribed burning -- Environmental aspects -- South Africa , Fire ecology -- South Africa , Tsitsa River catchment (South Africa) , Soil erosion -- South Africa , Grasslands -- Management -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145256 , vital:38422
- Description: South African grasslands are rich in flora and fauna and are a dominant vegetation cover in many of the water catchment areas, while providing a multitude of services to local communities and the environment. Fires have been the primary tool used to manage grasslands for livestock production for many years. However, there is debate about how they impact and alter landscapes and there are two schools of thought throughout literature. One argument is that fires are detrimental to landscapes; altering hydrological processes by causing excess soil erosion and changing soil properties. The other opinion is that fires are beneficial to ecosystems; maintaining vegetation structure, preventing bush encroachment, cycling nutrients and allowing for new plant growth. This study focused on the effects of fire regimes on soil properties in order to better understand the role that fire plays in geomorphic processes in the upper Tsitsa River catchment. The catchment falls under two land management types- commercial and communal, with the latter being severely degraded. Fire regimes were determined using a combination of Landsat and MODIS remotely sensed data and testing was carried out on soils exposed to different Fire Return Intervals (FRI). It was found that soils that were exposed to a high fire frequency (1-2-year FRI) exhibited a significantly higher degree of water repellency (p< 0.001) and surface hardness (p< 0.001) than soils that were exposed to a low fire frequency (3-4 year FRI), which indicates increased erosion potential. However, whilst a higher fire frequency resulted in altered soil characteristics, it contributed to landscape degradation as suggested in the literature, and soils are able to return to their previous state in over a short period of time. Further investigation into factors affecting fire regimes found that geology influenced vegetation type, resulting in differences in biomass in the two land management areas. The commercially managed land supported a high biomass, which resulted in a more natural fire regime with frequent fires, whilst the communally managed land supported less biomass. Smaller fuel loads and increased landscape fragmentation through overgrazing and road networks resulted in an altered fire regime with less frequent fires. Although the communally managed land has an altered fire regime, this research suggests that fires are not influencing the severe degradation present in these areas, and this is rather a function of geology and mismanagement of land. Whilst fire and grazing management plans can be implemented to alter the modified fire regime in the communal areas back to its natural state, this would take a long time and an increase in fires would pose a threat to surrounding communities. Overall the fire regimes in the upper Tsitsa River catchment are being altered by human influence and land management type, and whilst fire frequency is negatively altering soil properties, these soils can return to their natural state. The severe land degradation present in the communally managed areas are not a function of fire frequency and rather of geology and land management.
- Full Text:
- Date Issued: 2020
An investigation into the knowledge a Grade one teacher uses to develop the number sense of learners with mathematics learning difficulties
- Authors: Fleming, Kirsty Ann
- Date: 2020
- Subjects: Learning disabled children -- Education -- South Africa , Mathematics -- Study and teching (Elementary) -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/141533 , vital:37983
- Description: Learners in South Africa continue to underperform in the international and national mathematics benchmarking tests. In the primary school, poor performance in mathematics is viewed as an indicator of limited number sense. Since the end of Apartheid, there has been a proliferation of classroom-based research that attempts to explain why learners are underperforming and find solutions to the problem. Research that seeks to explain learner underperformance attributes poor learner performance to social-economic issues, teachers’ poor content and pedagogical knowledge, the complexity of the Language of Learning and Teaching, and insufficient support for learners with Mathematics Learning Difficulties (MLD). With regards to the latter, research suggests that Foundation Phase teachers are not equipped to assist learners with MLD develop their number sense. This qualitative case study aims to investigate the knowledge that an expert Foundation Phase teacher draws on, in the process of teaching, to assist learners with MLD develop their number sense. Data generated from observations and interviews with a Grade One teacher was analysed using Rowland, Turner and Thwaites’ (2013) Knowledge Quartet. The study found that the participant Grade One teacher employed all four categories of the Knowledge Quartet when developing her learners’ number sense. In particular, she placed strong emphasis on vocabulary development as a means of circumnavigating MLD when developing number sense in a Grade One mathematics lesson. She demonstrated knowledge of: the importance of vocabulary in learning mathematics; how to develop the learners’ understanding of mathematics vocabulary (and concepts); and how to adapt her approach to support the number sense development of learners with MLD. This research has value for teacher education programmes, both pre- and in-service, as it highlights the knowledge that a Grade One teacher draws on as she develops the number sense of all her learners, including those with MLD.
- Full Text:
- Date Issued: 2020
An investigation into the readiness of open source software to build a Telco Cloud for virtualising network functions
- Authors: Chindeka, Tapiwa C
- Date: 2020
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/124320 , vital:35593
- Description: Cloud computing offers new mechanisms that change the way networks can be created and managed. The increased demand for multimedia and Internet of Things (IoT) services using the Internet Protocol is also fueling the need to look more into a networking approach that is less reliant on physical hardware components and allows new networks and network components to be created on-demand. Network Function Virtualisation (NFV) is a networking paradigm that decouples network functions from the hardware on which they run on. This offers new approaches to telecommunication providers who are looking to new ways of improving Quality of Service (QoS) in cost effective ways. Cloud technologies have given way to more specialised cloud environments such as the telco cloud. The telco cloud is a cloud environment where telecommunication services are hosted utilising NFV techniques. As the use of telecommunication standards moves towards 5G, network services will be provided in a virtualised manner in order to keep up with the demand. Open source software is a driver for innovation as it is has a collaborative culture to support it. This research investigates the readiness of open source tools to build a telco cloud that supports functions such as autoscaling and fault tolerance. Currently available open source software was explored for the different aspects involved in building a cloud from the ground up. The ETSI NFV MANO framework is also discussed as it is a widely used guiding standard for implementing NFV. Guided by the ETSI NFV MANO framework, open source software was used in an experiment to build a resilient cloud environment in which a virtualised IP Multimedia Subsystem (vIMS) network was deployed. Through this experimentation, it is evident that open source tools are mature enough to build the cloud environment and its ETSI NFV MANO compliant orchestration. However, features such as autoscaling and fault tolerance are still fairly immature and experimental.
- Full Text:
- Date Issued: 2020
An investigation into the tax consequences for individuals performing work abroad
- Authors: De Ponte, Celeste Lidia
- Date: 2020
- Subjects: South Africa. Income Tax Act, 1962 , Income tax -- Law and legislation -- South Africa , Double taxation -- South Africa , International business enterprises -- Taxation -- Law and legislation -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/141235 , vital:37955
- Description: This thesis considered the income tax implications for South African tax resident individuals who render services abroad. The research included an analysis of the impact that the amendment to the section 10(1)(o)(ii) exemption has on individuals rendering services abroad and companies who send their employees abroad. In doing so, this thesis sought to highlight the key factors for consideration, for both employers and individuals. A doctrinal methodology was applied, and an analysis was carried out of relevant tax legislation, commentary of experts in the field of tax law and the relevant case law of South Africa, the United Kingdom (UK), Australia and the United States of America (US), where relevant. It was established that residency is key to determining the tax liability of a person and has an impact on the relief mechanisms that are available where double taxation arises. In addition, the amendment to section 10(1)(o)(ii) was considered. It was concluded that when rendering services abroad, both the employer and employee need to consider the tax consequences that may arise and highlights the factors which may be relevant. The thesis illustrates that, whilst the R1 million exemption alleviates the double tax consequences to a certain extent, further guidance is needed as to how the R1 million threshold will be calculated.
- Full Text:
- Date Issued: 2020
An investigation into the use of visualisation processes as a teaching strategy to enhance number sense
- Authors: Griqua, Ronald Max
- Date: 2020
- Subjects: Mathematics -- Study and teaching -- South Africa , Mathematics -- Study and teaching -- Psychological aspects , Visualization , Number concept , RUMEP (Rhodes University Mathematics Education Project)
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/147226 , vital:38606
- Description: The literature agrees that in order to improve learning outcomes, instruction in classrooms should be improved first. Mathematics educationists therefore advocate that schools should make extensive and deep efforts to rethink their instructional programmes. Research furthermore suggests that increasingly, indicators on school performance and teaching reveal largely unacknowledged problematic teaching of mathematics in the great majority of South African schools. This research study is therefore a contribution towards rethinking the teaching strategies within mathematics classrooms. The study examined the use of visualisation processes in order to understand how these interact with the pedagogy of selected mathematics teachers when they teach number sense after participating in an intervention programme. This study argues that the effective use of visualisation processes enhanced the teaching of number sense. The research study was framed as a case study that was grounded within the interpretive paradigm. The study was located in classrooms where the participating teachers promoted active learning after taking part in an intervention programme. A constructivist theoretical underpinning was therefore adopted. At the heart of the study was the Visualisation Intervention Programme (VIP), which involved seven Rhodes University Mathematics Education Project (RUMEP) teachers within the John Taolo Gaetsewe District of the Northern Cape Province. The content of the VIP was informed by initially working with five teachers of well-resourced schools within the Northern Cape who made interesting use of visualisation processes and manipulatives to teach number sense. With the assistance of these five teachers, the VIP was then implemented by seven selected RUMEP teachers to investigate the role of visualisation processes in the teaching of number sense understandings. The study employed a mixed method approach. Qualitative data was collected through observations and interviews, while quantitative data was collected with a series of pre- and post-tests. The analysis of the findings of this research study revealed that the effective use of visualisation processes was instrumental in enhancing the teaching of number sense understandings. Furthermore, the use of visualisation processes by the selected teachers fostered independent thought and conceptual understanding of number sense topics on the part of their learners.
- Full Text:
- Date Issued: 2020
An investigation of how selected Namibian grade 9 geography textbooks are reorienting school geography to education for sustainable development
- Authors: Uusiku, Naftal Amutenya
- Date: 2020
- Subjects: Geography -- Study and teaching -- Namibia , Geography -- Study and teaching -- Namibia -- Textbooks , Sustainable development -- Study and teaching -- Namibia , Environmental education -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/145524 , vital:38446
- Description: The World Social Science Report (UNESCO, 2013) describes environmental issues and challenges, many of which are driven by human activities. These include: changing consumption patterns, climate change, deforestation, desertification, water, population growth, poverty, food security, waste products and cultural diversity and globalization. Education for sustainable development [ESD], a vital tool for achieving the Sustainable Development Goals, requires a rethinking and reorienting of education to address sustainability (UNESCO, 2016). The International Geographical Union Commission on Geographical Education (2007, 2016) acknowledges the importance of reorienting of school geography to ESD. In Namibia, ESD has been embedded in the national curriculum. However, teachers play a critical role in reorienting school geography to ESD at the level of the classroom. They need appropriate resources to do so, the most widely used of which is the textbook. This study addresses the need for empirical research on how Namibian textbooks are reorienting geography to ESD. Using a qualitative interpretive research design, the study had the goals of understanding how selected Grade 9 textbooks are reorienting geography to ESD in what is taught (content) and how it is taught and learned (pedagogy), and how textbook authors perceive the reorienting of geography to ESD. Data were gathered through an online questionnaire of authors’ perceptions of their educational goals, important ESD content, the teaching strategies they use and the challenges they face. Document analysis was done on two causes of environmental deterioration — deforestation and population explosion in the theme Ecology — in three approved Grade 9 textbooks. The study provides evidence of how the selected textbooks are helping to reorientate school geography to the ESD content prescribed by the Namibian geography syllabus in a way that emphasizes knowing about, as opposed to critically engaging with the environmental challenges and issues at hand. With the exception of one textbook, the textbooks generally do not help to reorientate pedagogy to the transformative, change-oriented, futures-focused pedagogy advocated by the literature. Furthermore, the authors’ responses do not contain evidence that suggests their thinking is informed by contemporary perspectives on ESD or geography education. The findings provide insights for understanding how textbooks are helping to reorient Namibian school geography that may be of value to textbook authors and curriculum developers. Furthermore, it illuminates the need for theoretically informed curriculum and textbook writing workshops.
- Full Text:
- Date Issued: 2020
An investigation of the influence of knowledge-production and learning processes on complex practices in a community-driven citizen science initiative: A nature conservation case study
- Authors: Alexander, Jaclyn
- Date: 2020
- Subjects: Science -- Citizen participation , Western Leopard Toad Conservation Committee , Environmental education , Frogs -- South Africa
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/138173 , vital:37603
- Description: Community-driven citizen science initiatives have become an increasingly popular tool for combating social-ecological challenges that arise within communities. Scientific protocols have been designed to strengthen and support the accuracy and reliability of data collection and information sharing; however, little is understood of the dynamic social processes that reinforce and co-ordinate such community-driven action. This qualitative case study was undertaken to identify and understand complex organisational, political and socio-cultural processes (in particular knowledge-production and learning processes) that have guided, sustained and informed complex practices in a community driven citizen science initiative. The study aimed to inform the development of a social protocol that might be transferable to other citizen science contexts. The study drew on the theory of ‘Landscapes of Practice’, which highlights how multiple communities of practice overlap, interrelate, share knowledge and cross boundaries to create potential learning across a landscape. Additionally, ideas and typologies in recent citizen science literature offered perspective on the community-driven citizen science practices. This qualitative case study focused on the bounded case of the Western Leopard Toad Conservation Committee. Specific data generation tools (interviews, observations, document analysis and diagrams) were used from multiple perspectives over time to provide rigor and depth to the data. The study demonstrated how multiple ‘nexes of practice’ co-engaged in collective knowledge creation practices, which helped to enhance ‘knowledgeability’ across the landscape. This coordinated effort, however, was sporadic and inconsistent. Recommendations are made for the development of social protocols that could assist collaborators in citizen science initiatives to scrutinise and rethink their practices and to examine both their successes and shortfalls towards their shared interest.
- Full Text:
- Date Issued: 2020
An investigation of the internal challenges that hinder sustainability of the Furntech Nyanga incubates
- Authors: Sakuba, Siyasanga
- Date: 2020
- Subjects: Business incubators -- South Africa -- Cape Town , Business incubators -- Training of -- South Africa -- Cape Town , Entrepreneurship -- South Africa – Cape Town , Unemployment -- South Africa , Rate of return -- South Africa , Economic development -- South Africa , Training needs -- South Africa -- Cape Town , Furntech (Nyanga)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/142830 , vital:38121
- Description: The South African unemployment rate is currently at 27.6 per cent (Statistics South Africa, 2019). In an effort to combat unemployment, the South African government has implemented various mechanisms to provide opportunities to the people and combat unemployment. One of these mechanisms is to invest in the establishment of entrepreneurship incubators while the Furntech incubator is one of the incubators established for this purpose. It is imperative that the government spending on these mechanisms is justified by a return on investment which, in this case, should be to reduce unemployment and increase the overall entrepreneurial activity. In view of Furntech, with specific reference to the Nyanga incubation centre, there is a high failure rate with very little output of sustainable enterprises from the two-year incubation period. This study seeks to investigate the internal challenges that hinder the sustainability of these entrepreneurs to either drop out before the end of the two-year incubation period or to furnish the two years without becoming sustainable entrepreneurs. This study seeks to investigate this matter by using a semi -structured interview schedule that was geared towards investigating the research problem from the view of the incubates. The findings of the study showed that Furntech can be commended in respect of the transfer of technical skills. Furntech, however, failed to support the entrepreneurs with the other business support services that are part of their services, namely the business advisory, financial support and business skills. These findings provide a guideline of where Furntech needs to improve its service offering to gain a higher output of sustainable entrepreneurs. It is important to note that even though Furntech has representation in three provinces with two incubators in the Western Cape (Cape Town and Nyanga), however, this study was limited to the Furntech Nyanga incubates.
- Full Text:
- Date Issued: 2020
An investigation of the morphological and electrochemical properties of anode titanate materials used in li-ion batteries
- Authors: Gelant, Charmaine
- Date: 2020
- Subjects: Electrodes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48346 , vital:40851
- Description: The chemistry involved in the synthesis of lithium titanium oxide (Li4Ti5O12) for lithium ion battery applications is critical for understanding and optimizing the most cost-efficient manufacturing route. This study investigates the sol-gel synthesis technique of Li4Ti5O12 using triethanolamine (TEOA) as complexing agent by means of in-situ Powder X-ray Diffraction (PXRD). The influence of doping with various metals such as Al3+, Mg2+ , Co3+ and Ni2+ that were made as precursors was considered for comparison purposes due to literature showing improved electrochemical performance using the molecular formula of Li4Ti4.95M0.05O12. The in-situ PXRD technique was used to identify the phase changes that occurred in the thermal synthesis process from the sol-gel precursors to the final crystalline oxides. The materials’ decomposition mechanisms were characterized by thermal gravimetric analysis (TGA) as the precursors were gradually heated to obtain the final oxides. BET surface area analysis and scanning electron microscopy (SEM) were used in order to obtain a morphological understanding of the materials during the synthetic route at specific temperature regions. The in-situ studies have shown that the precursor materials are amorphous at room temperature to about 550 °C, after which the spinel and anatase formed, with relatively small crystallites and a large surface area. The study also showed that a crystalline intermediate phase formed at around 150-200 °C, which then disappeared above 250 °C and was speculated to be a titanium acid (H2Ti2O5.H2O). Upon further heating above 250 °C, the anatase phase converted to the high temperature stable TiO2 phase, rutile, also with an increased formation of the expected LTO spinel phase around 850 °C. Keeping the material at 850 °C, isothermally, did show further conversion of the rutile into the desired spinel phase Li4Ti5O12 (LTO) with an increase in the crystallite size and a decrease in surface area. SEM analysis of the material at 850 °C did show some extensive sintering of the particles with some samples indicating the presence of an additional β-Li2TiO3 phase that formed at the high temperatures. Upon cooling, the βLi2TiO3 phase showed a distinctive powder diffraction pattern besides the typical spinel II LTO phase. The study showed that in comparison to the oxide formed at 850 °C, a mixed phase material of the spinel LTO, anatase and rutile could be achieved at temperatures close to 650 °C with very small crystallites and a relatively large surface area that showed desirable electrochemical properties. Suitable Li-ion coin cells were built with the undoped spinel and doped materials that were isothermally made at 650 °C and 850 °C, whereby their electrochemical properties were tested in the form of cell capacity, electrochemical impedance spectroscopy (EIS) and differential capacity (dQ/dV) studies. The cells made with the materials at 850 °C provided reasonable capacity where the dQ/dV plots did show a single step redox reaction at around 1.5V vs Li/Li+ . These were compared to cells made with commercially available LTO and highlighted the importance of high surface area and small particle size of the active material in order to achieve acceptable electrochemical performances. The cells with the materials made at 650 °C showed to have good capacity upon the first discharge with a number of irreversible phase transitions that were subsequently not observed upon recharging. The dQ/dV graphs showed that the phase transitions were unique to the mixed phase composition of the material made at low temperatures and the cells made with the doped spinel materials were on average better performing than the undoped LTO material. Subsequent grinding steps of the active material made at 850 °C improved the capacity performance of the cells but were still lower when compared to the commercially available material. Hence, significantly longer grinding and processing time would be required to achieve battery active materials that are acceptable for commercial use. This study highlights the importance of understanding the phase transitions that occur during the synthesis route of making battery active material, where doping with different elements and using lower temperatures during synthesis could lead to electroactive materials that do not require additional excessive processing steps such as grinding.
- Full Text:
- Date Issued: 2020
An IT Risk Management Framework for provincial business entities : a case study for Limpopo Economic Development Agency, Limpopo Province, South Africa
- Authors: Mabitsela, Ngoakoana Unity
- Date: 2020
- Subjects: Risk management -- South Africa -- Limpopo Business enterprises -- Computer networks -- Security measures -- South Africa -- Limpopo , Information technology -- Security measures -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/49463 , vital:41723
- Description: This study focused on a lack of an Information Technology Risk Management (ITRM) framework tailored for provincial business entities to assist with the management of IT risks. The research was aimed at developing a tailored IT risk management framework that would assist provincial business entities with an effective ITRM process. This was achieved through identifying factors that constitute an ITRM framework, determining the current IT risk management methods used in provincial business entities and assessing the IT risk culture. This research study was conducted at the Limpopo Economic Development Agency (LEDA), which is a provincial business entity in the Limpopo province. The objectives of the study were accomplished using a design science research approach which involved the creation of an artefact and design theory as a means to improve the current state of practice as well as existing research knowledge about provincial business entities and their management of IT risks. The Nelson Mandela University Design Science Methodology Framework (NMU-DSFM) was identified as the methodology to be followed to devise the contribution in the form of an artefact. It was found that the organisation does not have a positive IT risk culture. From the study of the data analysis performed, it was evident that provincial business entities have challenges associated with adequately identifying IT risks. The findings highlighted that for the proper management of risks, risk governance should be effective by ensuring that the board of directors takes the responsibility of IT risk management, and the essentials of risk governance were discussed at length. The research output for this study was a framework. The adoption of this framework may positively contribute to strengthening governance of IT risk management in the provincial business entities. Best practices were highlighted for ease of reference to determine what is required and how to implement this regarding IT risk management.
- Full Text:
- Date Issued: 2020
An unsung dialogue: music, society and the history of The Flames
- Authors: Park, Duncan Keith
- Date: 2020
- Subjects: The Flames (Musical group) , Fataar, Steve , Durban (South Africa) -- History , Durban (South Africa) -- Race relations , Musical groups -- South Africa , Music -- Social aspects -- South Africa , Music -- Social aspects -- South Africa -- Durban , South Africa -- Politics and government -- 1961-1978
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/169632 , vital:41780
- Description: This research aims to examine the relationship between music and social conditions within the context of apartheid . The focus area is the city of Durban, specifically 1960-1970. A case study of the multi-racial Durban-based band, The Flames 1963–1972) will be used to rigorously assess the extent to which social conditions and music can affect each other in both directions. This will also be the first coherent and historical narrative of the band, The Flames. As such, the thesis aims to make an original contribution to this field of music history, while it will provide the very first academic discussion of The Flames. South Africa during apartheid, with its racialised legislation provides an ideal context to scrutinize the effects (both potential and real) of music on social conditions. The Flames provide a particularly relevant case point; being a collective of “mixed-race” individuals classified as Coloured performing for a multi-racial fan- base. This means that at their concerts, audience members would have frequently been from a variety of different racial backgrounds. This would have been in direct contravention to the National Party‟s (NP) Separate Amenities Act as well as the policy of “separate development”, the cornerstone of apartheid. The thesis will firstly contextualise the research within the broader, global historical context, as well as in the existing theoretical literature which focuses on the relationship between music, politics and society. Firstly, this will entail a brief historical account of popular music around the world during the twentieth century. Through this we will observe both the ways in which the development and popularisation of various forms of popular music came to be shaped in a particular way, as well as the ways in which the public received this music. This will include an examination of positive responses to certain kinds of popular music which resonated and became popular with various sectors of society. Conversely, it will also closely examine the backlashes against these musical forms, and attempt to identify why certain sectors of the public were deeply opposed to particular kinds of popular music which may have been perceived to embody certain values and meanings. This will be conducted by studying various forms of popular music from the turn of the twentieth century into the early 1970s with a cross-cultural, global perspective, examining particular historical instances and existing theories relating to these instances. Chapter one will then shift from a global perspective and will situate the research within the South African musical context specifically. This will include an account of the development of South African popular music through the twentieth century in relation to the country's politics. Through examining this relationship, the dialogue between historical case studies and theoretical literature will continue, in which existing theories relating to the relationship between music, politics and society will be discussed. This theoretical literature will be made use of in the final section of the paper in order to make sense of The Flames and their role in South African history. The second section of this thesis will focus on the socio-historical context of the city of Durban under apartheid. The author will contextualise the research through a narrative historical retelling of Durban‟s social history, focusing on both political and social public mobilisation and the role of cultural spaces and practices within these his torical moments and their relevant structures. Attention will be paid to the development of segregation and apartheid within Durban specifically, while racial relations will also be fo cused upon. This will provide the reader with the necessary background required in order to meaningfully understand how the band The Flames came into existence, became popular, and whether or not they had any meaningful effect on their historical context. The section on Durban's history will be followed by a brief account of Durban's Coloured community's history, as well as a discussion around Coloured identity more broadly within the South African context. This will be vital to the research due to the fact that the musicians of The Flames were classified as Coloured under apartheid, and such an historical background will be critical to understanding the social, political and economic context of the band. Finally, the thesis will end with the written history of The Flame . This final section will provide an account of The Flames' history in which the band will be made sense of within the context of Durban during apartheid, as well as within the context of South African music, and the globalised context of popular music. By situating the band within these three contexts, we can truly assess both how they were shaped by their contexts, and whether they had any effect on these contexts of which they were a part. In this section those existing theories around the relationship between music, politics and society will be discussed and assessed in order to determine how useful a framework they may be for understanding popular music in certain historical contexts. In this way, the research aims to make a meaningful contribution to the study of music and its socio-political role throughout history, as well as to the broader understanding of Durban's history. Specifically, the role of music in Durban's history is being examined, and the researcher hopes that this work can begin to open up new discussions around the importance of studying music in Durban, and South Africa's history. Additionally, this thesis will open up a new area of research into a band which, until this point, has not been engaged with in the field of music history whatsoever. .
- Full Text:
- Date Issued: 2020
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Mur amide ligases , Ligases , Ligand binding (Biochemistry) , Antibacterial agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/163430 , vital:41036
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
Analysis of bacterial Mur amide ligase enzymes for the identification of inhibitory compounds by in silico methods
- Authors: Chamboko, Chiratidzo Respina
- Date: 2020
- Subjects: Pathogenic microorganisms -- Analysis , Drug resistance in microorganisms , Microorganisms -- Effect of drugs on , Antibiotics -- Effectiveness , Pathogenic bacteria , Drug tolerance , Enzymes -- Analysis , Peptide antibiotics
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/161911 , vital:40690
- Description: An increased emergence of resistant pathogenic bacterial strains over the years has resulted in many people dying of untreatable infections. This has become one of the most critical global public health problems, as resistant strains are complicating treatment of infectious diseases, increasing human morbidity, mortality, and health care costs. A very limited amount of effective antibiotics is currently available, but the development of novel classes of antibacterial agents is becoming a priority. Mur amide ligases are enzymes that have been identified as potentially good targets for antibiotics, as they are uniquely found in bacteria. They are responsible for the formation of peptide bonds in a growing peptidoglycan structure for bacterial cell walls. The current work presented here focused on characterizing these Mur amide ligase enzymes and obtaining inhibitory compounds that could potentially be of use in drug discovery of antibacterial agents. To do this, multiple sequence alignment, motif analysis and phylogenetic tree constructions were carried out, followed by docking studies and molecular dynamic simulations. Prior to docking, homology modelling of missing residues in the MurF structure (PDB 1GG4) was performed. Characterization results revealed the Mur amide ligase enzymes contained defined conservation in limited regions, that ultimately mapped towards the central domain responsible for ATP binding (presence of a conserved GKT motif). Further analysis of results further unraveled the unique patterns observed within each group of the family of enzymes. As a result of these findings, docking studies were carried out on each Mur amide ligase structure. At most, two ligands were identified to be sufficiently inhibiting each Mur amide ligase. The ligands obtained were SANC00574 and SANC00575 for MurC, SANC00290 and SANC00438 for MurD, SANC00290 and SANC00525 for MurE and SANC00290 and SANC00434 for MurF. The two best ligands identified for each enzyme had docked in the active site of their respective proteins, passed Lipinski’s rule of five and had substantially low binding energies. Molecular dynamic simulations were then performed to analyze the behavior of the proteins and protein-ligand complexes, to confirm the lead compounds as good inhibitors of the Mur amide ligases. In the case of MurC, MurD and MurE complexes, the identified ligands clearly impacted the behavior of the protein, as the ligand bound proteins became more compact and stable, while flexibility decreased. There was however an opposite effect on MurF complexes, that resulted in identified inhibitors being discarded. As a potential next step, in vivo and in vitro experiments can be performed with identified ligands from this research, to further support the information presented.
- Full Text:
- Date Issued: 2020
Analysis of maximum power point tracking data for obtaining photovoltaic parameters
- Authors: Chitura, Anesu Godfrey
- Date: 2020
- Subjects: Photovoltaic power system
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18576 , vital:42610
- Description: As a standard, photovoltaic (PV) modules are rated by the use of standard test conditions (STC). Such details entail current and voltage (I-V) measurements for modules under an irradiance of 1000 W/m2 an air mass ration of 1.5 global spectrum and 25˚C cell temperature. Outdoor weather conditions continuously vary with time and from one location to the other. This further offset the expected operational power outputs as outdoor conditions are generally characterized by high cell temperatures. The technology one uses will also complicate the power output prediction since different module technologies respond to these outdoor conditions differently. I-V tracers are able to measure the full I-V curve of the module thus can give the operational PV parameters at any given time. However, these tracers are sold at exorbitant prices and they require skilled personnel in order to operate them. Most if not all tracers require isolation of the module under test thereby disrupting the power production function of the module._________________________________________________________________________________________________________________________________________ In this study a method to obtain photovoltaic (PV) parameters using the maximum power point tracking (MPPT) data is presented and tested under natural outdoor conditions. The method features a customized data acquisition system (DAS) designed for the measurement and storage of meteorological and MPPT data. The DAS is capable of extracting parameters from any combination of modules with an open circuit voltage 〖(V〗_oc) less than or equal to 120 Volts and a short circuit current 〖(I〗_sc) of 100 Amps. The system used is capable of extracting MPPT data using a reliable, improved storage and a programmable data logger. In order to match the sampling operational speeds of internal charge controller switches a computer interfaced Peripheral Component Interconnect (PCI) card was also used. Data collection and characterization of the MPPT data was done in such a way that the power generation process remained uninterrupted throughout the whole process. The regression nonlinear least squares method was used to fit MPPT crests and obtain the knee part of the I-V curve. This was then extrapolated to obtain the full I-V curve, which then produces the operational PV parameters. The resultant parameters from the characterization process were logged and accessible at any time. The end result was a method that can be incorporated within a charge controller for quick, hands-free PV parameter extraction, using only the MPPT scanned data.
- Full Text:
- Date Issued: 2020
Analysis of the contribution of socio-economic factors on poor academic performance of grade 12 learners: the case of Butterworth education district, Eastern Cape Province South Africa
- Authors: Lubisi, Anathi
- Date: 2020
- Subjects: Performance standards -- South Africa Teacher effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc (Sociology)
- Identifier: http://hdl.handle.net/10353/18141 , vital:42236
- Description: The drive of this research project was to discover factors contributing to the poor academic performance of Grade 12 learners at two selected schools in the Butterworth Education District, Eastern Cape province South Africa. The participants were Grade 12 learners, Grade 12 teachers and parents of Grade 12 learners in both schools. Both schools are located in rural areas of Mnquma municipality under the Butterworth education district. The study used both qualitative and quantitative research methods. The motivation behind using triangulation was to decrease or offset the deficiency of a specific methodology and for deeper understanding of the discoveries of the study. Use of triangulation in this study was aimed at expanding the legitimacy, dependability and generalizability of the results of the study. The findings of the study revealed that the most determining factor that contributes to the poor academic performance of Grade 12 learners in the Butterworth Education District is the unavailability and inadequacy of instructional resources. This is the most critical school resource which the parents cannot afford to buy for their children. Both teachers and Grade 12 learners indicated that they do not have a school library or a community library. The majority of learners also indicated that they do not have enough textbooks in all subjects and their parents concurred that their children end up sharing textbooks with their peers. Furthermore, the three groups of participants agreed that learners do not have access to computers, and the school does not have a science lab for Grade 12 learners doing science. The core argument of this study is that a poor socio-economic background is a primary contributor to low academic performance of Grade 12 learners at the Butterworth Education District. The findings of this study support this thesis as they indicate that instructional resources are inadequate, a school or community library is vii non-existent, and there is not enough textbooks at the selected schools. With parents from low socio-economic background, the Butterworth community is also not in a position to supplement these insufficient instructional resources. This study utilized the cultural reproduction theory of Bourdieu (1977) to explore a system of education in industrialized communities and the way it works to illuminate class differences in academic performance and achievement of Grade 12 learners. The study made recommendations that should be put in place to improve the academic performance of Grade 12 learners in the Butterworth Education District. The most important of these recommendations is that government officials should provide educational resources (teaching and learning resources). Furthermore, the researcher suggest that for further research, it would be interesting to find out about learners that perform well, regardless of identified factors that cause other learners to perform poorly to help them improve their academic performance.
- Full Text:
- Date Issued: 2020