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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.
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  • 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.
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  • Date Issued: 2020

An integrated analytical framework for analysing expansive learning in improved cook stove practice:

  • Authors: Jalasi, Experencia Madalitso
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149043 , vital:38798 , https://doi.org/10.1016/j.lcsi.2020.100414
  • Description: This paper reveals relationships between four analytical frameworks, boundary interaction, reflexivity, transformative agency, and Sannino's reformulated Vygotskian double stimulation model in an Integrated Analytical Framework (IAF) used to analyse expansive learning processes via Boundary Crossing Change Laboratory Workshops in the development of will and volitional actions. I show how transformation emerges from expansive learning processes using two Transformative Pathways in Improved Cook Stove (ICS) practice in Chapita Village case study in Malawi. Introduction of ICSs in the traditional cooking practice generated conflict of motives within subjects of interacting activity systems. I used Cultural Historical Activity Theory (CHAT) to identify and analyse the conflict of motives using socio-cultural historical analysis and analysis of contradictions around learning, promotion, and utilisation of the ICS.
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  • Date Issued: 2020

An integrative approach to understanding vulnerability of an alpine range-restricted bird to climate warming

  • Authors: Oswald, Krista Natasha
  • Date: 2020
  • Subjects: Passeriformes -- South Africa -- Western Cape , Passeriformes -- Physiology -- South Africa -- Western Cape , Passeriformes -- Behavior -- Climatic factors -- South Africa -- Western Cape , Passeriformes -- Reproduction -- Climatic factors -- South Africa -- Western Cape , Passeriformes -- Dispersal -- South Africa -- Western Cape , Passeriformes -- Food -- South Africa -- Western Cape , Passeriformes -- Nests-- South Africa -- Western Cape , Blue Hill Nature Reserve , Cape Rockjumper -- Climatic factors , Chaetops frenatus
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/148517 , vital:38746
  • Description: Understanding species' vulnerability to climate change requires an integrative ecological approach involving, at minimum, physiology, behaviour, reproductive success, and limitations on dispersal. In this thesis I determined potential negative effects of increasing temperatures on behaviour, reproduction, and ability to disperse in an alpine-restricted bird, the Cape Rockjumper Chaetops frenatus ("Rockjumper"). Here I provide a comprehensive ecological set of data for understanding the link between Rockjumper population declines and warming habitats. I tested whether Rockjumper microsite-use at high temperatures resulted in decreased time spent on important behaviours, such as foraging. I found Rockjumpers made increased use of rock-shade as air temperature increased and so spent less time panting, but birds in rock-shade foraged less. Birds may be constrained to foraging in sun at high temperatures to sustain energy or water requirements, despite risks of high thermal load, or else face lost foraging opportunities by remaining in rock-shade. I determined if adult nest attendance and causes of nest failure were related to high temperatures. I filmed nests over two breeding seasons to examine temperature-effects on adult time in nests, provisioning rate, and resultant nestling daily mass gain. The only temperature effect I found was decreased percent daily change in body mass for older nestlings at hotter temperatures. I also examined causes of nest failure over three breeding seasons in relation to nest concealment and habitat openness by observing failure/success. Nests in more open territories (i.e. early post-fire habitat) had greater success, and the main cause of predation came from Boomslang Dispholydus typus. Importantly, the probability of Boomslang predation increased significantly at hotter temperatures. These findings show there may be direct negative effects of increasing temperatures on reproductive success and population recruitment, and so hotter temperature during the breeding season may be at least partly responsible for observed population declines. Lastly, I examined genetic structure of populations across mountain ranges separated from one another by lowland habitat unsuitable for Rockjumpers. I predicted I would find little evidence for dispersal between mountain ranges separated by unsuitable lowland habitat, but instead found Rockjumpers show little evidence for inbreeding. I also found evidence for a past bottleneck event or founder effect, and little overall genetic diversity (possibly as their specialized niche exerts selective pressure). Low diversity may limit Rockjumpers' ability to adapt to a changing environment. Adult physiological and behavioural thresholds to increasing temperatures are often used to create predictions of climate change effects. My past physiological research and current behavioural research suggest no particularly strong evidence that temperature-related population declines are driven by poor physiological capacity to tolerate heat or negative behaviour trade-offs. Instead, my current research shows that understanding negative effects of increasing temperatures may require a more in-depth approach involving investigation of fine-scale ecological interactions. No single one of my chapters provides the insight necessary for understanding Rockjumper population declines at warming temperatures. Instead, I show how an integrative approach may be necessary for assessing species' vulnerability to climate change by examining multiple ecological aspects of a single sentinel species, using an alpine species with a narrow thermal range and highly specialized habitat niche.
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  • 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.
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  • Date Issued: 2020

An intervention on supporting teachers’ understanding of and mediation of learning of stoichiometry in selected schools in the Zambezi Region

  • Authors: Denuga, Desalu Dedayo
  • Date: 2020
  • Subjects: Stoichiometry -- Study and teaching (Secondary) -- Namibia , Chemistry -- Study and teaching (Secondary) -- Namibia , Participant observation -- Namibia , Constructivism (Education) -- Namibia , Pedagogical content knowledge -- Namibia , Continuing education -- Namibia , Teachers -- In-service training -- Namibia
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/103855 , vital:32315
  • Description: This study has been triggered by the results on stoichiometry questions in the Directorate of Namibian Examination Assessment’s (DNEA) scripts. As highlighted in the examiners’ reports, stoichiometry is an ongoing annual problem for most students in Namibia. It is against this background that I decided to explore the possibility of an intervention in the form of continuing professional development (CPD) and collaboration workshops to improve the understanding and the mediation of learning of stoichiometry by Physical Science teachers in the Zambezi Region of Namibia. The study was underpinned by an interpretive paradigm and within this paradigm a qualitative case study approach was adopted. Since this study was in a form of an intervention, a participatory action research (PAR) approach was employed within the community of practice (CoP). I used document analysis, workshop discussions, observations and videotaped lessons, interviews (semi-structured and stimulated recall interviews) and reflections to gather data. The study was carried out at three senior secondary schools and six Physical Science teachers were involved. The study drew on the theory of constructivism as a theoretical framework, namely, Piaget’s cognitive constructivism and Vygotsky‘s social constructivism as well as Shulman’s pedagogical content knowledge (PCK). Within PCK, Mavhunga and Rollnick’s Topic Specific Pedagogical Content Knowledge (TSPCK) was used as an analytical lens (Appendix L) in this study. The findings reveal that the use of a diagnostic test on learners made the Physical Science teachers aware of the learners’ challenges and what was difficult for them to understand in stoichiometry. It also helped in their understanding of the use of prior knowledge, one of the tenets of TSPCK, to access what learners knew about stoichiometry. Further findings of the study illuminate that the Physical Science teachers’ subject matter knowledge, pedagogical content knowledge and skills had shifted as a result of their participation in the intervention workshops. The findings of this study indicate that the CoP members acquired the professional transformations which were important breakthroughs in their careers. The study thus recommends that teachers should develop effective teacher professional development activities such as study teams, exemplary lessons, cluster teaching, and peer coaching where teachers are expected to examine their assumptions and practices continuously. The implication of my study is that the developed exemplary lesson during the intervention workshops by CoP members could be useful to other Physical Science teachers in the teaching of stoichiometry in all the schools in the Zambezi Region.
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  • Date Issued: 2020

An investigation into the application of Distributed Endpoint Processing to 3D Immersive Audio Rendering

  • Authors: Devonport, Robin Sean
  • Date: 2020
  • Subjects: Uncatalogued
  • Language: English
  • Type: thesis , text , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/163258 , vital:41022
  • Description: Thesis (MSc)--Rhodes University, Faculty of Science, Computer Science, 2020.
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  • 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.
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  • 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.
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  • 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.
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  • Date Issued: 2020

An investigation into the nature and adequacy of tax compliance tools available to assist small businesses in the state of Oklahoma in the United States of America

  • Authors: Cary, Cindi L
  • Date: 2020
  • Subjects: Tax administration and procedure -- United States , United States. Internal Revenue Service , Small business -- Oklahoma , Small business -- United States , Taxpayer compliance -- Oklahoma , Taxpayer compliance -- United States
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/141015 , vital:37937
  • Description: This study identifies and analyses the effectiveness of the tax tools available to the small businesses that make up more than 99 per cent of all businesses in the United States and the state of Oklahoma through an extensive investigation of the small business resources offered by federal and state government agencies, higher education institutions and the professional accounting community. The study uses numerous measurements in order to acquire multiple perspectives and relies on the examination of government websites and documents, interviews, experiments, surveys, and questionnaires to determine the existing small business tax tools and their limitations. The research offers an in-depth analysis of the facts and limitations of the small business services offered by the Internal Revenue Service (IRS). The IRS is determined the largest source of small business tax tools, but limitations plague their effectiveness. Higher education is found guilty of not providing small business education in business or accounting disciplines, leaving college graduates ill-prepared to assist small businesses. Higher education is urged to implement a small business accounting curriculum that couples field experience with classroom lectures and textbooks. This study finds the accounting profession apathetic with regard to informing small businesses of accounting services and presses certified public accountants to be more involved in the education of future small business accountants. The study concludes with recommendations to reduce the small business tax burden by improving the existing small business tax tools.
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  • 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.
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  • 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.
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  • 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.
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  • 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.
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  • Date Issued: 2020

An investigation of the experiences of psychotherapists regarding Ubuntu in their psychotherapy practice: an interpretative phenomenological analysis

  • Authors: Qangule, Lumka Sybil
  • Date: 2020
  • Subjects: Ubuntu (Philosophy) , Psychotherapy -- Cross-cultural studies , Psychoanalysis and culture -- South Africa , Xhosa (African people) -- Psychology , Xhosa (African people) -- Mental health , Black people -- South Africa -- Psychology , Black people -- South Africa -- Mental health , Psychotherapists -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/146923 , vital:38577
  • Description: Psychotherapy is a Eurocentric concept and practice that has migrated to South Africa with technology, as part of the general transfer of knowledge (Mkhize, 2003). It has embedded Eurocentric principles that sometimes do not easily accommodate working with Africans. It has been practised by psychotherapists of African origin with clients of African origin, but is based upon Eurocentric ideas and guidelines for practice. Many African people consider their core values to be uBuntu, rooted in a principle ‘umntu ngumntu ngabantu’ (translated as ‘a human being is a human being because of other human beings’). Some important features of uBuntu are interdependence, respect, spirituality and the primacy of communality as an approach to life. Some of the ways in which these impact on daily functioning are not foregrounded by adherence to Western principles. The use of only Eurocentric principles when working with clients of African origin may thus not lead to the desired outcomes in psychotherapy. However, these Eurocentric principles are recognised and enforced by the authoritative bodies in the field of psychology, such as the Health Professions Council of South Africa. A distinction will be made between the more inflexible ethical principles of psychology and the ideas of therapy frames. Therapy frames are not seen as being as rigid as ethical codes and they could be augmented, to be appropriate for the context, particularly in the commonly multicultural settings that are found here. Psychotherapists of African origin are torn between abiding by the ethical principles that they have been taught and practising in the way that they, together with their clients, have been socialised. Abiding by the principles as described in the codes is safe because it does not pose any threat of being sanctioned by the regulator of practice, but clients may be let down and there may be limited success with certain clients. This clash of ideas of ways of practice poses dissonance and many dilemmas among psychotherapists of African origin. Due to the nature of this study, Interpretative Phenomenological Analysis (IPA) was adopted as a suitable methodology, where eight practising amaXhosa psychotherapists were interviewed about their experiences of incorporating uBuntu in their psychotherapy practice. The raw data from initial interviews were analysed and the findings concluded that although psychotherapists were trained in Western ways of practice, they included some practices of uBuntu in their practice as well as upholding some Eurocentric principles that seemed to be helpful for their clientele. Subsequently a summary of the findings were discussed with participants in a focus group setting, where participants endorsed and expanded upon their original responses. With the above in mind, a psychotherapy model called uBuntu-Centred Psychotherapy was created, which reflects the principles and therapy frames that have been found to be useful in treating clients of African origin. This modality is more congruent with the worldviews and style of living of many South Africans, in the post-apartheid era. It embraces some Eurocentric principles that are relevant for Africans, while it is embedded in the phenomena and way of life reflected in uBuntu, a predominant mode of functioning for the group that was the focus of this study, the amaXhosa. The study ends by making recommendations for practice, as well as highlighting the need for further and more extensive research to contribute to the project of Africanising psychotherapy.
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  • 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.
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  • 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.
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  • Date Issued: 2020

An investigation of the link between Financial sector development and economic growth in Zimbabwe from 1980 -2016

  • Authors: Machokoto, Sydney
  • Date: 2020
  • Subjects: Financial institutions-- Zimbambwe , Economic growth, development,planning -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/49894 , vital:41814
  • Description: This study investigated the link between financial sector development and economic growth in Zimbabwe from 1980 to 2016 using the Auto Regressive Distributed Lag model. Market capitalization as a ratio of gross domestic product (GDP), bank credit to the private sector as a ratio of GDP and financial assets of microfinance as a ratio of GDP were used as proxy variables for financial sector development. Economic growth was measured by real GDP. The Granger causality test indicated bi-directional causality between access to financial services and economic growth in Zimbabwe in the long run. Market capitalization and bank credit to the private sector did not Granger cause economic growth in Zimbabwe. It was recommended that the government should promote the functioning of the capital market as it is the conduit for providing long term capital to businesses. Bank credit to the private sector was found to be statistically significant. It was recommended that the government should promote decentralization of the banking sector to rural areas. The proxy variables of financial development used were statistically significant in influencing economic growth. The findings from the study led to the recommendation to open additional microfinance companies in remote areas and to increase the supply of financial services and products. Empirical evidence indicates that the link between financial development and economic growth depends on the proxy variables of financial sector development used in econometric modelling. The model was tested for heteroscedasticity, serial correlation, stability and normality. The econometric tests conducted were all satisfactory. This made the model ideal for policy formulation and recommendation.
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  • 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.
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  • Date Issued: 2020
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