Showing items 141 - 160 of 3700

An It risk management implementation strategy for a non-profit organisation in south africa

  • Authors: Exner, Ulandi
  • Date: 2022-12
  • Subjects: ITIL (Information technology management standard) -- South Africa , Nonprofit organizations -- South africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/59370 , vital:62075
  • Description: All organisations, for-profit or non-profit, have strategic objectives as their raison d’être. The achievement of these objectives is challenged by the occurrence and impact of unexpected events, commonly referred to as risks. The Digital Revolution in the late 70s introduced computers and the internet and opened up a whole new way of life. It also brought new challenges, namely IT risk. IT risk is business risk. Non-profit organisations, whose main priority is to maximise its available resources to serve the needs of their stakeholders and community, do not have adequate IT risk management practices in place because it is not top of mind for them. An effective IT risk management strategy provides several enhanced capabilities for organisations. Non-profit organisations have IT risk management standards, frameworks and methodologies to choose from, but these organisations do not have the required financial means and expertise or possibly the necessary appetite to implement these frameworks successfully. The primary objective of the study is to develop a proposed IT risk management implementation strategy for non-profit organisations to aid in the management of IT risk. The design science research paradigm was used for the study. Qualitative and quantitative research methods were used to understand the current landscape of a non-profit organisation in so far as their approach to managing IT risk. The findings of the literature review and mixed method research were used to develop a proposed IT risk implementation strategy. The evaluation of the implementation strategy in terms of its effectiveness and utility will form part of a future study. The proposed implementation strategy can be considered as an instrument for the NPO to aid in the management of IT risk. The conclusion of this study contributes to the field of IT risk research of non-profit organisations in South Africa. , Thesis (MA) -- Faculty of Engineering, the Built Environment, and Technology, 2022
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  • Date Issued: 2022-12

Beauty from Ashes:short term postfire regeneration of dune fynbos -thicket vegetation in the South Eastern Cape floristic region

  • Authors: Gcina, Sinenjongo
  • Date: 2022-12
  • Subjects: Fynbos ecology – Nelson Mandela University Campus Nature Reserve , Forest fires -- Prevention and control
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/59666 , vital:62319
  • Description: Aim This study aims to provide an understanding and a description of the short-term postfire regeneration and ecology of the fynbos-thicket vegetation on a coastal dune system in the southeastern Cape Floristic Region. Another aim is to assess the recovery of the vegetation community by assessing the growth forms and the disturbance response across a range of species from thicket and fynbos communities and to provide a belowground bud bank classification for each of these species in the coastal dune systems. Location The study site was the Mandela University Reserve and the Noordhoek dune fields, situated in Gqeberha, Eastern Cape, which is part of the south-eastern Cape Floristic Region. The study site hosts thicket-fynbos mosaic vegetation type that occurs in a Mediterranean-Climate Ecosystem (MCE). Methods Firstly, field observations and photographs of plant species were taken weekly to assess and identify the species that were emerging and persisting in the dune system in the first 12 months postfire. Phenological events of the species that emerged (e.g., flowering, fruiting, leaf growth, leaf yellowing, and leaf abscission) were also observed and reported on. Secondly, an excavation of 21 species (e.g., Jamesbrittenia microphylla, Euclea racemosa, Olea exasperata, Searsia laevigata) was conducted to classify the species into their belowground bud bank types. Results There was a rapid emergence of resprouters (facultative resprouters and obligate resprouters) in the first 12 months postfire. This was followed by their growth; primarily occurring after the rainfall events. The dominant resprouting species (facultative resprouters and obligate resprouters) entered the system two weeks after the fire. There was a significant difference in the time to the first emergence of the different regeneration groups postfire (P < 0.001): on average, obligate sprouters (OS) appeared 1 month after fire – two months earlier than facultative sprouters (FS) and four months earlier than non-sprouters (NS). There was no statistical evidence to suggest that the FS and non-sprouters NS emerged at different times postfire; however, most NS species were observed in the system 5 months after fire. 4 Exceptions were the NS species Pelargonium grossularoides and Mesembryanthemum aitonis, both annuals that emerged 1 month after fire. A wide range of OS species that appeared earlier in the system (e.g., Euclea racemosa, Olea exasperata, Searsia laevigata, and Lauridia tetragona) exhibit underground lateral growth with belowground bud banks (BBBs) from which they recover after disturbance. In total, six BBB types were recorded in this study, namely: bud-bearing root, rhizome, rhizophore, woody rhizome, stem tuber, and corms. The bud-bearing root from woody species was the dominant BBB in this system. Main conclusion The return of species that occurs in the first year after fire occurs rapidly in the first 2 months as resprouting species (primarily OS) appear in the system. Following this, the rate of return of species decreases as reseeding species (primarily NS) gradually reestablish and occupy the gaps in the dune fynbos-thicket vegetation. This study has shown that plant species in this ecosystem are adapted to fire disturbance as their populations are able to reestablish through various regeneration strategies, including resprouting from different types of BBB. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
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  • Date Issued: 2022-12

Characterising termite mound spatial patterns in the Eastern Cape Karoo : applying drone remote sensing,GIS and spatial statistics

  • Authors: Mngcele, Lizalise Sive Nqaba
  • Date: 2022-12
  • Subjects: Drone aircraft in remote sensing – Eastern Cape Karoo , Termites , Geographic information Systems – South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/59555 , vital:62169
  • Description: The Eastern Cape Karoo in South Africa has been earmarked for potential Shale Gas development, which has necessitated the understanding of existing ecosystems to be quantiĄed pre-development, in order to have a baseline against which the exploration can be monitored. Termite mounds as baseline mechanisms, are known to be sensitive to ecosystem disturbance and because of their abundance in the exploration zone, have been studied as indicator species. They are both a surface and subsurface phenomena which makes them an ideal baseline monitoring mechanism. Termite mound height, basal circumference and geospatial data was collected against natural and anthropogenic factors: elevation, vegetation, water, soil, geology, human settlements and roads. Mound distributions were observed across four study sites, and seven plots, using a DJI Phantom 4 Pro drone, an aerial and ground survey. Observed mound data on the drone and aerial survey was compared to that of the ground survey. Overall, the drone survey outperformed the aerial survey in recording accurate termite mound data. This was largely attributed to the scale of the study which gave the drone a competitive advantage. It allowed for drone data to be collected at 40 m altitude with an image resolution of 2-6 cm/pixel on each plot. In addition, drone detection accuracy was improved through the ability to generate digital surface models (DSMs) through point clouds and overlaying them with orthomosaics. Considering observed mound spatial point patterns, both the drone and aerial survey were more than 50% percent consistent with the ground survey, although the drone survey detected 28.57% more accurate mound spatial point patterns than the aerial survey. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
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  • Date Issued: 2022-12

Economic impact assessment of the national youth development agency (NYDA) grant fund in the Eastern Cape

  • Authors: Fotoyi, Asanda
  • Date: 2022-12
  • Subjects: Economic impact analysis , Youth development, Eastern Cape
  • Language: English
  • Type: Doctoral's theses , Thesis
  • Identifier: http://hdl.handle.net/10948/59424 , vital:62093
  • Description: Since the dawn of democracy in South Africa, the country has adopted several youth policies aimed at promoting young peoples’ education and training, employment, entrepreneurship, and healthy lifestyles. Still, however, the country battles high youth unemployment rates, which increased from 35.7% in 2010 to 41.0% in 2019. Such issues exist despite the NYDA being established in 2008 to coordinate youth strategies in the country. The NYDA strategic areas include: economic participation, education and skills development, health and wellbeing, knowledge management, and governance. Of note is that NYDA grant funding has been specifically designed to provide young South African entrepreneurs with an opportunity to access both financial and nonfinancial business support to establish or expand their businesses. Over a period of 7 years (2013-2019), the NYDA has grant funded a significant number of youth-owned businesses across the country, to the value of about R204.5 million. Given the large amount of public funds invested through NYDA grant funding, it is important to assess whether or not this investment has been favourable in terms of achieving its goals. This determination is especially important, as governmental resources are scarce and subject to opportunity cost, in that some alternatives have been forgone in favour of the NYDA mandate. The present study was, therefore, necessary, as, since the inception of NYDA grant funding, its economic impact has not been scientifically measured or assessed. As such, there has not been any scientific basis to justify NYDA grant funding. In particular, this thesis assessed the economic impact of the NYDA grant funding in the Eastern Cape. The effectiveness of the NYDA grant funding was examined against its objectives: improved entrepreneurship participation, business skills development and support, and improved creation of job opportunities. The primary hypothesis was tested using a cost-benefit analysis (CBA). The CBA method was adopted as it is a well-established economic assessment method to test policy interventions. This method is also based on methodological rigour and was determined to be most applicable for this present research endeavour. v The notion behind using the CBA was to quantify the net benefits of NYDA grant funding for youth businesses by comparing the benefits with the corresponding costs. In order to determine other factors that influence the turnovers of NYDA grant funding recipients’ businesses, secondary hypotheses were then tested by using a least absolute deviation (LAD) regression analysis in respect to cross-sectional data relating to the respondents’ annual turnovers over the years 2014-2019. The LAD estimation method was used primarily due to its robustness in comparison to ordinary least squares (OLS). This study made use of a questionnaire to collect data on the demographics of the NYDA grant funding beneficiaries. As well as the beneficiaries’ business characteristics, their subjective perceptions on the impact of the NYDA support interventions, and business-specific challenges. The Raosoft calculator was used to calculate the sample size at a 5% margin of error. The scientifically sound sample size of the respondents, according to the Raosoft calculator, was 246 out of 681 clients. The respondents were drawn from the Eastern Cape areas by means of face-to-face survey interviews as well as a digitised research instrument that was circulated using several online platforms (e.g., email, WhatsApp, and Facebook). The total number of respondents who ultimately participated in this study was 253. In order to achieve Denzin’s (1978) triangulation, a focus group session was also conducted with selected NYDA grant beneficiaries. The focus group discussion for this research was held using the online platform, Microsoft Teams (MS Teams). The survey analysis findings of the study suggest that the demographics of the NYDA grant funding beneficiaries are a general reflection of the Eastern Cape’s overall youth entrepreneurship trends. As such, there were more male youth entrepreneurs compared to female youth entrepreneurs. The involvement of youth in business improved in correspondence with age -groups. The population groups of the grant funding beneficiaries also reflected the country’s racial demographics. In terms of business characteristics, the survey analysis findings revealed that NYDA grant funded businesses function across various sectors of the economy and largely operate out of homes. These businesses primarily serve local households and communities, have generally been operating for 3-5 years, and were largely started because the owner recognised an opportunity in the market. In terms of business assistance from vi NYDA, it was found that the grant funding was mostly utilised for asset finance. In terms of business challenges, market conditions were highlighted as negatively impacting youth businesses. However, the participating business owners were primarily inward-looking when seeking to address their challenges. A further finding from the survey analysis revealed that many NYDA grant funded businesses tended to increase the number of jobs created in the period under review. The CBA findings, in turn, showed that the public expenditure in Eastern Cape youth businesses through NYDA grant funding was economically viable during the period under review, since the benefit-cost ratio (BCR) exceeded ‘1’ (the net present value (NPV) was also positive). The regression estimation findings further indicated gender, education, and industry gross domestic product (GDP) growth rates also had a significant impact on the annual turnovers of the youth businesses. The focus group findings highlighted that most beneficiaries derive value from NYDA grant funding. However, there is scope for improvement in the areas of access to finance, turnaround times, access to markets, links to the entrepreneurship ecosystem, administrative burden, mentorship, monitoring and evaluation (M&E), and organisational culture. Based on the findings of the study, this thesis concludes that in the period under review, in the Eastern Cape, NYDA grant funding yields positive social returns; and delivered on its objectives (i.e., improved entrepreneurship participation, business skills development and support, and improved creation of job opportunities). The empirical findings of this study further supports this thesis’s recommendation for: 1) improvements in the NYDA grant funding budget; 2) closing gender gaps in youth entrepreneurship; 3) improving participation of disabled youth in business support services; 4) promoting entrepreneurship as a career path; 5) providing youth business support in rural areas; 6) diversifying economic sectors of youth businesses; 7) offering access to finance for youth business growth and expansion; 8) establishing youth businesses access to markets; 9) reducing administrative burdens for youth businesses; 10) improving accessibility of business development trainings; 11) offering mentorship for youth entrepreneurs, 12) providing infrastructure for youth businesses; 13) extend Covid-19 relief support for youth businesses; and 14) standardising practises in youth business support services. , Thesis (PHD) -- Faculty of Business and Economics Science, 2022
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  • Date Issued: 2022-12

Evaluation of the mesozooplankton functional diversity indices in Algoa Bay as proxies to assess the stability of the food chain leading to the African penguin (Spheniscus demersus)

  • Authors: Rukuni, Praxedes Vimbai
  • Date: 2022-12
  • Subjects: Marine zooplankton --South Africa -- Algoa bay , Penguins -- South Africa -- Conservation , Fishes -- Predators of -- South Africa -- Algoa Bay
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/59956 , vital:62698
  • Description: Current unprecedented environmental changes threaten food web and ecosystem stability, which is particularly concerning in areas with vulnerable species such as the endangered African penguin Spheniscus demersus. In this study I adopted a holistic approach integrating many ecosystem levels to better understand African penguin behavioural ecology and food web stability. I investigated interplay between physico-chemical parameters and zooplankton functional diversity at various temporal and spatial scales in Algoa Bay. The study further investigated the applicability of zooplankton functional diversity (FD) in inferring African penguin food web stability by comparing the FD of zooplankton found in anchovies regurgitated from African penguins and the ones found in the Bay PELTER Stations. Gut contents of anchovies regurgitated from Bird Island and St Croix penguins were also evaluated using Frequency of Occurrence and Dominance methods and compared between colonies. Zooplankton FD in Algoa Bay varied over time but not at spatial scales with chlorophyll-a, Sea Surface Temperature (SST), turbidity and salinity being potential drivers of zooplankton FD. Chlorophyll-a and salinity were positively correlated with FD, meanwhile FD was inversely correlated to turbidity and SST. The study also observed minor differences in the physico-chemical parameters associated with African penguin foraging grounds, though different dietary preferences were found between the anchovies regurgitated from penguins from the two colonies. Anchovies regurgitated by penguins from Bird Island targeted large sized groups such as Decapods, meanwhile anchovies from the St Croix penguin colony targeted small sized Ostracods and Cirripedia. This study therefore, provides insight on the influence of fluctuations in physico-chemical parameters in shaping zooplankton communities in Algoa Bay. The study also emphasises anchovy dietary plasticity, switching from selective feeding to opportunistic feeding in instances of prey shortages which contributes to a stable African penguin food web in the face of climate change. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
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  • Date Issued: 2022-12

Knee Joint Competence Post Anterior Cruciate Ligament Reconstruction in Amateur South Western Districts Rugby Players

  • Authors: Potgieter, Quinten Christiaan
  • Date: 2022-12
  • Subjects: Neuromuscular depolarizing agents , Knee--Wounds and injuries -- South Western Districts , Rugby Players
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/60266 , vital:64289
  • Description: Background: Globally, literature has shown that rugby players struggle to return to the same level of performance post anterior cruciate ligament (ACL) reconstruction. This phenomenon is further exacerbated amongst South African Rugby players, compounded by the ranking of the national team amongst the top ten rugby teams worldwide. Paired with the psychosocial aspect of return to play, the physical and physiological competence of the knee joint is of pivotal importance. Purpose: To compare relative dynamic stability scores paired with electromyography (EMG) scores between the injured and uninjured legs, thereby enabling an explorative, descriptive report on dynamic proprioceptive abilities post ACL reconstruction (ACLR). The study findings therefore aim to inform rehabilitative practice in a rugby player who underwent ACLR. Study Design: A quantitative, explorative and descriptive design was used, with a purposive sampling strategy. Methods: Biographical and anthropometrical data was measured upon inception. Muscular activation was measured using electromyography (EMG) placements on quadriceps muscles which included the vastus medialis obliques (VMO), and vastus lateralis (VL). Dynamic proprioception was measured using the star excursion balance test (SEBT) and normalised to leg length. A neuromuscular fatigue protocol was used to measure the impact of neuromuscular fatigue on dynamic stability, and muscle activation between the injured and uninjured lower limbs. Results: A sample of 15 participants from the South Western Districts (SWD) rugby team, fitting the inclusion criteria, were included in the study. The average age was 27±2.7 years. The results indicated that fatigue did not significantly affect the SEBT scores between the injured and uninjured lower limbs. However, the VMO muscle activation showed a statistically significant difference in muscle firing in a pre-fatigue state. This difference was evident in two of the eight directions namely anteromedial direction (p = 0.041), and in the lateral direction (p = 0.047). Furthermore, these result differences were favoured in the uninjured limb. No significant differences between the injured and uninjured lower limbs were found in respect to VMO and VL muscle activation, in a fatigued state. vi Conclusion: Practically translated, the study results showed that the injured lower limb, showed no significant differences in dynamic stability during both the non-fatigued and the fatigued SEBT. Therefore, the finding of this study is a steppingstone towards informing return to play criteria for adequate dynamic knee stability and proprioception. It should be noted that further research is necessary to refine return to play criteria and thereby decrease the risk for re-injury. Keywords: anterior cruciate ligament; dynamic stability; neuro-muscular fatigue; reconstruction; re-injury; return-to-sport; rugby. , Thesis (MA) -- Faculty of Health Sciences, 2022
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  • Date Issued: 2022-12

The effect of limestone ammonium nitrate and chicken manure fertilizers on growth, yield and quality of two cabbage cultivators

  • Authors: Nongogo Chumani
  • Date: 2022-12
  • Subjects: Cabbage -- South Africa , Field crops -- Nutrition -- South Africa , fertilizers
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/59922 , vital:62695
  • Description: Cabbage is a well-known and popular crop in South Africa. As a highly nutritious leafy green vegetable, it is produced and sold to a variety of markets, from formal markets to hawkers, for human consumption and as animal feed. The cabbage crop contributes positively to food security, health, and households’ financial wellbeing. As a crop, cabbage is known to be a heavy feeder due to its high nutritional requirements (in terms of fertiliser) particularly nitrogen. This high requirement can be supplied by either synthetic or by organic fertilisers in the form of animal manures. However, fertiliser has proven to be a challenge due to its high costs, as its prices increase rapidly each year. The current study aimed to determine the most effective fertilisation method for the growth, quality, and yield of cabbage (Brassica oleracea var. capitata). Two fertiliser types (chicken manure and limestone ammonium nitrate) were applied, and the treatments were repeated five times over two planting sessions on two cultivars, Grandslam and Empowa, at concentrations of 0%, 100% and 150%. A control for each treatment / cultivar was also grown. The parameters plant height, head diameter, pests and disease development, quality and dry mass were measured to determine the effect on growth, yield, and quality of the cabbage crop. From each planting, a total of 60 cabbages served as specimens for data collection purposes. The research trial was conducted in open field and laid out in a split-plot block method. The cultivar was allocated to the main plot, while the fertiliser treatments served as the sub-plots. The study was carried out for a period of six months, which allowed for data collection to be done in two different growing conditions. Planting was done manually by hand in planting bags, and washed river sand was used as a substrate (growing medium). The data collected during the experiment was analysed by means of statistical data analysis software STATISTICA and the methods applied were a three-way analysis of variance (ANOVA). The analysis of variance was performed at a significance level of p as a means to determine a correlation of relationships for all set parameters (variables) for both cultivars, treatments and plantings. The results of the study showed that the two fertiliser types, namely limestone ammonium nitrate (LAN) and chicken manure, both had a significant effect (p on plant height, head diameter, dry mass. Also, the pest and disease development and quality of cabbage were significantly influenced by the fertiliser types and season (climate). The interactive effect of cultivar and fertiliser was statistically significant. Empowa showed better results on chicken manure compared to LAN. In the case of Grandslam, however, no significant fertiliser effect was observed. The study also showed that fertilisation with a fertiliser that contains high nitrogen (N) content promotes pest and disease incidence. Increasing N application rate resulted into an increase of pest and disease incidence. The change of season, which promotes different growth conditions (in terms of temperature, water requirements, pests, and diseases) for the plants was found to have had an influence on the study results. Lasty, it was observed that chicken manure fertiliser yields a cabbage with a good internal and external quality compared to limestone ammonium nitrate fertiliser. Lastly, when considering all treatment rates applied, the recommended quantity of 100% (in both chicken manure and LAN) yielded favorable results. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
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  • Date Issued: 2022-12

Barriers to utilisation of antenatal care services in Bloemfontein, sub-district of Mangaung Metro, Free State, South Africa

  • Authors: Montshiwa, Kgalalelo Christine
  • Date: 2022-11
  • Subjects: Prenatal care
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/26995 , vital:66212
  • Description: Background: Maternal and child mortality remain a global health problem, regardless of preventative measures put in place. Antenatal care is crucial to decrease maternal and child morbidity and mortality. However, in Bloemfontein, the sub-district of Mangaung Metro in the Free State, it has been identified that women utilise this kind of service sub-optimally. The study aimed to explore and describe barriers to the utilisation of antenatal care by pregnant women in the Bloemfontein sub-district of Mangaung Metro. Methodology: This study was qualitative and used an explorative, descriptive design. Qualitative data was collected by using focus group discussions and key informants’ interviews. Three focus group discussions with twenty-five pregnant and lactating mothers, aged between 18 and 49 years, were conducted. Participants took part in one focus group discussion at each healthcare facility. Four key informant interviews were conducted with four facility managers and one professional midwife who conducted ANC at the clinic at the time of the study in the three healthcare facilities. A thematic analysis process was used to analyse the collected qualitative data under each identified barrier. The STATA version 15 was used in the analysis of the demographic characteristics of the participants. Results: Most of the participants indicated that they are aware of the importance of attending ANC appointments however, they have voiced that the delayed waiting times and staff attitudes contribute to how they feel about visiting a clinic early. Some of the participants mentioned that they have cultural barriers as they still believe that a traditional pregnant woman should not reveal her pregnancy in the early days but must rather wait until her stomach has grown significantly for her to visit the clinic. Two participants indicated that they had unplanned pregnancies and wanted to do an abortion, but their religious beliefs prevented them to choose to terminate their pregnancies. Economically, not all participants complained about their financial situation though the majority were unemployed and single. Participants from the Bloemspruit facility complained of transport as they stay far from the clinic and they are sometimes forced to walk alone which makes it difficult to attend all their booked sessions with their midwives. The results of the study revealed that there are several factors contributing to late antenatal care attendance namely provider and personal factors contributing to late antenatal care attendance in the Bloemfontein sub-district of Mangaung Metro. Personal factors that were found to be contributing to late antenatal care booking were lack of transport, especially for Bloemspruit participants, unwanted pregnancy, lack of financial support, lack of partner support, cultural and religious beliefs, and lack of knowledge. Provider factors that were found to be contributing to late booking were lack of resources like tools of the trade, long waiting times, poor infrastructure, human resources, and midwives’ attitudes. Recommendations. To deploy qualified midwives to conduct antenatal care clinics, to extend the service over the weekends as participants mentioned that they struggle to get time off from work during the week. Health promotion and community awareness campaigns on the importance of antenatal care may increase the utilisation of antenatal care services. , Thesis (MPA) -- Faculty of Health Sciences, 2023
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  • Date Issued: 2022-11

Spatial assessment of riparian vegetation condition in relation to water quality: a case of the Keiskamma River, Eastern Cape Province, South Africa

  • Authors: Teyise, Anda
  • Date: 2022-11
  • Subjects: Water quality , Riparian plants , Stream health
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/27679 , vital:69393
  • Description: Riparian vegetation plays several roles in ecological functioning, such as improving water quality because it can filtrate the sediments and provides stability on the floodplain. The condition of riparian vegetation can serve to provide information regarding river condition. The main purpose of this study was to investigate the extent to which water quality level of the Keiskamma River can be explained by the riparian vegetation density patterns. This study used Sentinel-2 Multi-Spectral Instrument (MSI) satellite image to assess spatial patterns in riparian vegetation condition. The Normalized Difference Vegetation Index (NDVI) was generated from the Sentinel-2 imagery and was used as the base from which riparian vegetation density classes were obtained through the supervised image classification technique. The image classification accuracy assessment was caried out to verify and validate the accuracy of riparian vegetation density classes. This technique produced the overall accuracy (OA) classification of 83.72 percent. The riverine water quality parameters were measured on the randomly surveyed sites using the Premium Series PC60 5-in-1 Water Quality Tester. High density of riparian vegetation were found in the upper course of the river. The low-density riparian vegetation dominates the middle course of the river while the lower part of the river contains a mixture of the three riparian vegetation conditions. The one-sample t-test statistical technique was carried out to determine the spatial pattern of water quality parameters. The t-test results revealed the significant variation in water pH, with the p-value of 0.00. However, t-test results also showed insignificant variations in water Total Dissolved Solids (TDS) and electrical conductivity (EC), with p-values of 0.117 0.059 and 0.059 respectively. The linear regression was used to determine the relationship between riparian vegetation and water quality. In this case, the NDVI values were used as surrogate for riparian vegetation condition. The results showed insignificant relationships between NDVI and water pH (r2 = 0.00), NDVI and water TDS (r2 = 0.09), and NDVI and water EC (r2 = 0.09) along the Keiskamma River. In view of the findings obtained from this study “spatial differences in riparian vegetation along the lateral and longitudinal dimensions of the Keiskamma River denote spatial variations in water quality levels”, is rejected. , Thesis (MSci) -- Faculty of Science and Agriculture, 2022
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  • Date Issued: 2022-11

Teacher's perspectives on the implementation of HIV/AIDS policy in OR Tambo Inland Education District: A case study of five selected schools

  • Authors: Tebekana, Jongiwe
  • Date: 2022-11
  • Subjects: Teaching strategies
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/11260/10842 , vital:75288
  • Description: This thesis explored teachers’ perspectives in implementing HIV/AIDS policy in the O. R. Tambo Inland Education District. HIV/AIDS is one of the greatest challenges in the world and is crippling almost every aspect of society (politically, socially, financially, and educationally). In the education sector, it affects teachers, learners, their families, and the communities at large. Governments everywhere, especially Education Ministries, developed policies to combat the pandemic. In South Africa, the National Policy on HIV/AIDS for learners and teachers for public schools and students in Further Education and Training Institutions was published in 1999. The Department of Education also developed guidelines for teachers, to assist them in managing HIV/AIDS issues in Public Schools. Theoretically, this study was informed by the implementation theory of Pressman and Wildavsky (1973) who view policy implementation as a procedure of collaboration between the establishments of objectives, and Elite/Mass theory which implore that the key people in authority, who are considered as the elite group, determine policy without considering its implementation on the ground. This is a qualitative case study based on interpretivism, which strives to comprehend how individuals in everyday settings construct meaning and explain the events of their world. Purposive sampling was employed to identify twelve rich informants (teachers) from five purposively selected primary schools. Data were collected through document analysis, semi-structured interviews, and field notes. Findings reveal that teachers have insufficient knowledge about HIV/AIDS policy which they are expected to implement, they were insufficiently trained, lacked support, and encountered some barriers towards the implementation of HIV/AIDS policy. The study recommends that that professional in-service development programme should be developed by the Department of Basic Education (DBE) for all qualified Life Orientation (LO) teachers since HIV/AIDS is an aspect of the LO subject and DBE should increase school-based support visits by subject specialists to ensure that there is proper monitoring. It further recommends that policy formulators should engage the implementers in policy dissemination through meetings, newsletters, conferences, debates, circulars and networks like cluster and circuit networks to eradicate distortion of crucial policy information for implementation. It is further recommended based on the findings and informed by the two theoretical frameworks of Implementation and Elites/Mass theories, Tebekana Collaborative Policy Formulation, and Implementation model for the benefit of the schools is proposed. , Thesis (D.Ed) -- Faculty of Education Sciences, 2024
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  • Date Issued: 2022-11

A critical analysis of the tax treatment of cryptocurrencies in a South African context

  • Authors: Ho, Dau-Ming
  • Date: 2022-10-14
  • Subjects: Cryptocurrencies Taxation , Income tax Law and legislation South Africa , Income tax Law and legislation Australia , Financial services industry Security measures , South Africa. Income Tax Act, 1962
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/357504 , vital:64749
  • Description: The aim of the present research was to investigate whether, as claimed by the South African Revenue Service in the media release issued in April 2018, the normal income tax provisions could apply to cryptocurrency transactions. To achieve this aim, a literature review was undertaken to describe the nature of cryptocurrencies and related crypto mining activities, providing definitions of cryptocurrencies, blockchains and crypto mining, as well as describing the functioning of the system. The research then proceeded to analyse the provisions of the definition of “gross income” in section 1 of the Income Tax Act, 58 of 1962, as amended, and the requirements of the “general deduction formula” in terms of the preamble to section 11, section 11(a) and section 23(g), as applying to cryptocurrency transactions. The application of other provisions in the Act to cryptocurrency transactions was analysed, including trading stock in terms of section 22, and capital allowances in terms of sections 11(e), 12C and 13quin of the Act, together with capital gains tax consequences in terms of the Eighth Schedule to the Income Tax Act. The regulation for income tax purposes of cryptocurrency transactions in Australia was discussed, with a view to making similar recommendations in South Africa. The research was situated in the interpretative paradigm, a doctrinal methodology was applied, together with a qualitative analysis of documentary data. The discussion was limited to the income tax consequences of cryptocurrencies as applying to individuals. The findings of the research were that, in general, the normal income tax provisions could apply to cryptocurrency transactions, but based on the analysis of the South African and Australian income tax acts as they apply to cryptocurrencies, it was recommended that a Comprehensive Guide on the income tax consequences of cryptocurrency transactions should be issued by the South African Revenue Service, together with amendments to section 25D and paragraph 43 of the Eighth Schedule to the Income Tax Act to deal with the conversion of cryptocurrencies to Rand values, and to section 9C of the Income Tax Act to include the deemed capital nature of the disposal of cryptocurrencies in the three-year rule presently applying to equity shares. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2022
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  • Date Issued: 2022-10-14

Application of systems theory for analysing the sustainability foci and practices of the Faculty of Economics and Information Technology Systems: (A Case Study of Walter Sisulu University: Komani campus)

  • Authors: Klishi, Konwaba Bomikazi
  • Date: 2022-10-14
  • Subjects: Sustainable development Study and teaching (Higher) South Africa Mthatha , System theory , Curriculum evaluation South Africa Mthatha , Community engagement , Walter Sisulu University for Technology and Science
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405281 , vital:70157
  • Description: Sustainable development is a global concern that intertwines several factors, including poverty, biodiversity, inequality, water, and energy. This interconnection does not only affect the current generation but may have long term implications for future generations as we see the rapid spread of environmental risk in our local communities. In this study, systems theory was adapted for analysing the sustainability focus of the Faculty of Economics and Information Technology Systems (FEITS) at Walter Sisulu University. A qualitative research method was used during this research, and data collected from a purposive sample of staff, activities and documentation. In this study, Von Bertalanffy’s systems theory is applied to analyse the sustainability foci and practices of the FEITS. The study describes sustainability practices and concerns that emerge from research activities, community engagement activities and work-integrated learning. The theory is also used to analyse the connection between various subsystems of the faculty when addressing emerging local sustainability concerns. Education for sustainable development is an important aspect of this study as it considers the sustainability concerns in the curriculum from the perspective of current and future alternatives for the economy and socio-ecological aspects of communities. The following findings have emerged from the study: Contextual realities related to inequality were foci of discussion and concern in various qualifications. Socioecological issues and risks were found to be related to water and sanitation, food security and climate change. Sustainability discourse is related to health and wellbeing, peace, and security. There is an alignment of green skills to the curriculum of the faculty and pedagogical practices which relate to sustainability. The faculty participates in stakeholder platforms to respond local sustainability challenges and is developing courses in response to local development needs. This study has implications for the faculty’s curriculum in terms of the content of various qualifications, future research, and community engagement activities of the university. , Thesis (MEd) -- Faculty of Education, Education, 2022
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  • Date Issued: 2022-10-14

Big T’s and small T’s: an explorative study on trauma narratives in South Africa

  • Authors: Naidoo, Rinisa
  • Date: 2022-10-14
  • Subjects: Psychic trauma , Anthropology , Mental health South Africa , Apartheid South Africa Personal narratives , Culture Psychological aspects
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/408641 , vital:70512
  • Description: The 21st century has seen a dramatic increase in chronic non-infectious diseases, especially in the area of mental health. Medical anthropologists have seen a rise in the development of mental illnesses in both developed and developing nations. There is, however, little research conducted on trauma narratives that do not stem from political violence from an anthropological lens. South Africa has various understandings of trauma depending on the cultural context and it is crucial to examine these narratives as this provides vital information of the daily lived experiences of trauma survivors. Key themes draw on issues of trauma denialism, communicating distress, traumatic symptoms and the development of mental illnesses as a result of traumatic exposure. The data was analysed through Goffman’s (1959) Presentation of Self in Everyday Life illustrating various ways how survivors present themselves depending on the particular audience. This research employed both qualitative and quantitative research methods to gather a holistic understanding of trauma survivors. With the use of semi-structured interviews of Stressful Life Events Questionnaire coupled with observations of online support groups for trauma survivors, this research has provided rich ethnographic evidence of the impact that culture has on trauma narratives illustrating a clear normalcy of trauma present in South Africa. , Thesis (MSocSci) -- Faculty of Humanities, Anthropology, 2022
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  • Date Issued: 2022-10-14

Effect of Helicosporidium sp. (Chlorophyta; Trebouxiophyceae) infection on Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae), a biological control agent for the invasive Salvinia molesta D.S. Mitchell (Salviniaceae) in South

  • Authors: Mphephu, Tshililo Emmanuel
  • Date: 2022-10-14
  • Subjects: Salvinia molesta South Africa , Weeds Biological control , Cyrtobagous salviniae , Ketoconazole
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/365815 , vital:65792 , DOI https://doi.org/10.21504/10962/365815
  • Description: The effectiveness of established biological control agents depends on biotic and abiotic interactions in the introduced range. The weevil, Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae), was released as a biological control against Salvinia molesta D.S. Mitchell (Salviniaceae) in South Africa in 1985. This agent has been highly successful against S. molesta and has significantly reduced the weed’s populations around the country. However, in 2007, the parasitic alga, Helicosporidium sp. (an undescribed species), was detected in field-collected C. salviniae adults in South Africa. The distribution and impacts of this disease on the weevil and its efficacy as a control agent were not known. In this thesis, the prevalence, infection load, and impact of Helicosporidium sp. on C. salviniae was determined. In 2019, adult weevils were collected from 10 sites across the Eastern Cape, KwaZulu-Natal, Limpopo, and Western Cape provinces and screened to determine the occurrence, infection load, and geographic distribution of Helicosporidium sp. Transmission mechanisms of this disease in C. salviniae were then evaluated. The possible impact of Helicosporidium sp. was assessed by comparing the feeding rates and the reproductive output of the diseased and healthy adults of C. salviniae. An attempt was then made to eliminate the disease in C. salviniae through the application of the antibiotic, ketoconazole. Further, the role of temperature on infection load in C. salviniae was also assessed. Finally, recommendations for the long-term biological control programme against S. molesta in South Africa were made. The disease covers the entire distribution range of C. salviniae in South Africa, with the disease occurrence rate ranging from 92.15% to 100% insects infected per site. Helicosporidium sp. was found to transmit vertically within the populations of C. salviniae. Infection by the Helicosporidium sp. disease reduced the reproductive output of C. salviniae as well its impact on biomass reduction of S. molesta when a diseased culture was compared to a healthy culture from the USA. 98.44 to 98.55% of Helicosporidium sp. loads were reduced through multiple applications of ketoconazole concentrations under in vitro trials. In vivo treatments resulted in 70% control of Helicosporidium sp. in the adults of C. salviniae that were fed ketoconazole three times over a 21 day period. Adult C. salviniae feeding and survival performances were similar when fed fronds of S. molesta inoculated with ketoconazole and water. The lowest and highest disease loads of Helicosporidium sp. were recorded when the weevils were reared at 30°C and 14°C, respectively. As expected, the highest impact and reproductive output of C. salviniae were at 30°C. The evaluations discussed in this thesis highlight the role of diseases in biological control agents, and gaps in both the pre-release and post-release monitoring that should integrate screening of diseases in these studies. Although the combined application of the antibiotic and temperature will reduce Helicosporidium sp. loads and impact, this technology is most likely only applicable where the weevils are reared in small numbers in a rearing facility and not really applicable to the field situation. It is important to release healthy agents that will cause efficient control of the target weed plant species, therefore, when introducing new biological control agents, the health status of such agents needs to be understood. Therefore, long-term field monitoring and assessment of the impact of C. salviniae on S. molesta should be conducted to track all the changes that may result due to the presence of Helicosporidium sp. This long-term monitoring and assessment will give a more informative role of Helicosporidium sp. in field populations of C. salviniae. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
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  • Date Issued: 2022-10-14

Evaluating the trophic ecology and feeding habits of three divergent lineages of Sandelia bainsii (Teleostei: Anabantidae), from the Eastern Cape Rivers using stable isotope analysis

  • Authors: Nkomo, Thulisile
  • Date: 2022-10-14
  • Subjects: Anabantidae , Trophic ecology , Food chains (Ecology) , Food web , Freshwater fishes Food , Stable isotopes
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/364984 , vital:65667
  • Description: Despite supporting a disproportionately large fraction of the global biodiversity, freshwater ecosystems are ranked as the most highly threatened habitats on the planet, ahead of both terrestrial and marine ecosystems. Many regions are still characterised by limited knowledge regarding the taxonomy and ecology of freshwater fish taxa. The need for ecological information is increasingly becoming important due to the discovery of new species and unique lineages, which require conservation management. The aim of this study was thus to evaluate the trophic ecology and feeding habits of the three recently described and divergent Sandelia bainsii lineages, namely Sandelia sp. ‘bainsii Kowie’ from the Great Fish River, Sandelia sp. ‘bainsii Keiskamma’ found in the Keiskamma River, and Sandelia sp. ‘bainsii Buffalo’ confined to the Buffalo River system in the Amathole-Winterberg freshwater ecoregion in the Eastern Cape Province, South Africa. Based on the allopatric distribution and the generalist feeding habits of these lineages, this thesis postulated that these three lineages were likely to show similar trophic ecology patterns, different dietary composition and as a result would have variable trophic positioning in the different river systems. Therefore, the primary objectives were to use stable isotope analysis to (1) evaluate the food web patterns of the river systems where the three S. bainsii lineages occurred, and (2) determine dietary source contributions for the three lineages using isotope mixing models. The results revealed general variability and significant differences in the δ13C and δ¹⁵N values for the different basal resources, macroinvertebrates and fish community across the different headwater streams. Within and across the different rivers, the S. bainsii lineages exhibited variable isotopic niche sizes, which appeared to coincide with the variation in the isotopic composition of the individual communities. Furthermore, these lineages did not exhibit any discernible patterns in their interspecific interactions in different habitats. This suggests that these lineages’ isotopic niche patterns were largely influenced by spatial differences in both trophic resources and probable interactions with contraspecifics. Assessment of trophic positions of S. bainsii lineages showed that the three lineages had higher trophic positions than other co-occurring species at most sites, except in the Buffalo River. This suggest that the different lineages were generally top predators in the different river systems. Although S. ‘bainsii Buffalo’ had a lower trophic position compared to other co-occurring species, its trophic position was generally characterised by high uncertainty, indicating that this lineage was likely influenced by the occurrence of diet sources that had highly variable stable isotope values. Findings from stable isotope mixing models revealed that the diet sources varied from the dominance of either single diet source in the Fairburn and Tyume 1 River to the importance of multiple prey sources from the Lushington and Kat River system. This suggests that despite being a top predator at most sites, the diet sources for the different lineages were highly variable. The patterns observed in this study did not appear to be attributed to species divergence possibly caused by allopatric speciation, but rather differences in food web characteristics of the river systems, as well as the lineages interspecific relationships and their generalized feeding strategies. Understanding the trophic dynamics of these lineages will assist in implementing effective conservation strategies and policies dealing with narrowly distributed species that are threatened by habitat fragmentation and invasion of piscivorous fish. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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  • Date Issued: 2022-10-14

Exploring primary school mathematics teachers use of gamification in formative assessment: a case study

  • Authors: Simelane, Thando
  • Date: 2022-10-14
  • Subjects: Kahoot! , Gamification , Technological Pedagogical Content Knowledge , Mathematics Study and teaching (Elementary) Eswatini Shiselweni , Educational technology , Formative assessment
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/405412 , vital:70169
  • Description: Technology integration has gained much influence with the emergence of technological tools in educational areas. The vast resources and opportunities that technologies and the Internet have brought new approaches, strategies, and tools to assess learners' performance in many subject areas. Teachers have many computer/mobile device applications and learning management systems. Most teachers are trying new ways of integrating technology into the mathematics classroom to increase the quality of teaching and learning. Thus, this study explored how primary school mathematics teachers use Kahoot as a formative assessment tool. The study adopted an exploratory case study underpinned by the interpretive paradigm. It was conducted in a primary school in the Shiselweni Region in Swaziland. The participants were ten mathematics teachers teaching different grades at the school. Data was generated using observations, workshops, structured questionnaires, journal reflections and focus group interviews. The theoretical and analytical framework that underpinned this study was a combination of Davis' (1989) Technology Acceptance Model (TAM) and Mishra & Koehler's (2006) Technological Pedagogical Content Knowledge (TPACK) framework. The study results showed that the perceptions and attitudes of primary school mathematics teachers towards using Kahoot generally appear to be positive. The study also revealed that all the participants found Kahoot helpful and perceived it as easy to use. The study found that the provision of technical support for teachers; and financial support for schools to implement technology use in the classroom were enabling factors for using Kahoot as a formative assessment technology. Constraining factors were lack of high-speed internet connectivity; and lack of basic technological knowledge for using Kahoot in formative assessment. The study concluded that Kahoot increases learner motivation, engagement, attention, enjoyment, and knowledge retention. This study recommended the integration of Kahoot gamification into the mathematics curriculum.The study recommends that there is a need for schools to initiate the presence of technologies in mathematics classrooms and encourage teachers to integrate technologies assessment and teaching. The study suggest future research to explore use of Kahoot as a formative assessment technology in resource-constrained schooling contexts using multiple cases. , Thesis (MEd) -- Faculty of Education, Education, 2022
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  • Date Issued: 2022-10-14

Fucoidans from South African brown seaweeds: establishing the link between their structure and biological properties (anti-diabetic and anti-cancer activities)

  • Authors: Mabate, Blessing
  • Date: 2022-10-14
  • Subjects: Fucoidan , Diabetes Treatment , Cancer Treatment , Brown algae
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/365677 , vital:65775 , DOI https://doi.org/10.21504/10962/365677
  • Description: Type 2 diabetes mellitus (T2DM) and cancer are major non-communicable diseases causing a heavy morbidity-mortality and economic burden globally. The therapeutic efforts in managing these diseases are primarily chemotherapeutic and are associated with demerits, including side effects and toxicity, limiting the prescribed amounts. These dosage limits may cause drug resistance, another major challenge in maintaining quality global health. The pursuit of novel natural bioproducts is a reasonable strategy to add to the arsenal against T2DM and cancer. Fucoidans, sulphated fucose polysaccharides abundant in brown seaweeds, have recently become popular for their biological activities, including anti-diabetic and anti-cancer properties. However, endemic South African brown seaweeds have not been adequately explored. Therefore, this study sought to characterise fucoidans extracted from South African brown seaweeds and elucidate their structure to their biological activities. Also, this study highlighted carbohydrate and glucose metabolism as major target processes in the control efforts of T2DM and cancer using fucoidans. Harvested brown seaweeds were identified as Ecklonia radiata and Sargassum elegans. E. maxima was kindly donated by KelpX. The fucoidans were then extracted using hot water, EDTA assisted, and acid extraction protocols. The integrity of the extracted fucoidan was confirmed through structural analysis using FTIR, NMR and TGA. The fucoidan extracts were then chemically characterised to determine their carbohydrate and monosaccharide composition and sulphate content. The characterised fucoidans were profiled for inhibiting the major amylolytic enzymes, namely α-amylase and α-glucosidase. The mode of inhibition by fucoidans and synergy experiments with the commercial anti-diabetic drug acarbose were also investigated. Furthermore, the fucoidans were screened for potential anti-cancer activities on the human colorectal HCT116 cancer cell line. The cytotoxicity of fucoidans was quantified using the resazurin assay. The effect of fucoidan on HCT116 cell adhesion on the tissue culture plastic was also investigated using the crystal violet-based cell adhesion assay. In addition, cancer antimigration properties of fucoidans were also investigated using 2D wound healing and 3D spheroid-based assays. Furthermore, the long-term survival of HCT116 cells was investigated through the clonogenic assay after treatment with fucoidans. Lastly, glucose uptake and lactate export assays revealed the influence of fucoidan on glucose uptake and the glycolytic flux of HCT116 cells. Fucoidans were successfully extracted with a yield between 2.2% and 14.2% on a dry weight basis. EDTA extracts produced the highest yields than the water and the acid extracts. Ecklonia spp. fucoidans displayed the highest total carbohydrate content, with glucose and galactose being the major monosaccharides. S. elegans and commercial Fucus vesiculosus had lower carbohydrate contents but contained more sulphates than the Ecklonia spp. fucoidans. Furthermore, the extracted fucoidan contained little to no contaminants, including proteins, phenolics and uronic acids. In addition, the extracted fucoidans were determined to be >100 kDa through ultracentrifugation. Mass spectrometry also detected the most abundant peak for all fucoidans to be around 700 Da (m/z). Extracted fucoidans inhibited the activity of α-glucosidase more strongly than the commercial anti-diabetic agent acarbose but were inactive on α-amylase. Fucoidans were also shown to be mixed inhibitors of α-glucosidase. Compellingly, fucoidans synergistically inhibited α-glucosidase in combination with the anti-diabetic agent acarbose, highlighting prospects for combination therapy. Finally, fucoidans demonstrated some anti-proliferative characteristics on HCT116 cancer cells by inhibiting their ability to adhere to the tissue culture plate matrix. Furthermore, some fucoidan extracts inhibited the migration of HCT116 cancer cells from 3D spheroids. Some of our fucoidan extracts also inhibited HCT116 colony formation, demonstrating inhibition of long-term cell survival. The E. maxima water extract also inhibited glucose uptake by HCT116 cells, thereby influencing the glycolytic flux. In conclusion, biologically active fucoidans were successfully extracted from South African brown seaweeds. These fucoidans demonstrated anti-diabetic and anti-cancer properties, revealing their relevance as potential drugs for these diseases. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2022
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  • Date Issued: 2022-10-14

Functional biogeography: evaluating community assemblage patterns and ecosystem functioning in intertidal systems using trait-based approaches

  • Authors: Gusha, Molline Natanah C
  • Date: 2022-10-14
  • Subjects: Biogeography , Marine algae , Benthic ecology , Invertebrates , Functional redundancy , Ocean temperature , Biology Classification
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/365792 , vital:65790 , DOI https://doi.org/10.21504/10962/365792
  • Description: Analyses of taxonomic diversity patterns within coastal systems has been critical in the development of the theory of biogeography. Increasing evidence, however, shows that the variety of functions that species perform in ecosystems (rather than their taxonomic identity) is a better predictor of the influence of the environment on the species. This information has been useful in predictive ecology leading to the development of trait-based approaches (TBA). Until the late 1970s, however, limited effort (particularly in marine systems) was channeled towards patterns in functional species traits and how they may be affected by changes in environmental gradients. Here, I mapped the functional biogeography of the South African coastline based on a suite of species' reproduction and development traits. Because species composition is one of the key tools used by zoogeographers to map species distribution patterns, I expected lower variability in trait composition within main biogeographic regions than in intervening transition zones based on the habitat templet theory and following the biomass ratio and limiting similarity hypotheses. In brief, the habitat templet theory proposes that “the habitat provides a templet upon which evolution forges species characteristics”, while the biomass ratio hypothesis assumes that the most abundant species traits determine ecosystem functioning. The limiting similarity hypothesis also sometimes referred to as the niche complementarity hypothesis, however, predicts that species can coexist if their niches complement one another. In light of the habitat being an evolutionary templet, abiotic and biotic habitat patterns were measured as nearshore SST and chlorophyll-a gradients, respectively. I expected the SST gradient to act as the stronger key filter of trait diversification because temperature is often considered the most influential environmental factor affecting species survival with seasonality of SST affecting the timing of spawning and along with food availability, possibly influencing fecundity. Functional trait data were thus compiled for macroinvertebrate species collected from fifty-two rocky shore sites from three main bioregions (east, south, and west) and two transition zones (south-west and south-east). Biological trait analysis and functional diversity indices were used to evaluate how traits related to species development and reproduction respond to temperature and chlorophyll -a (used as a proxy for food availability) gradients along the coastline. GLMM and hierarchical cluster analyses showed distinct patterns/shifts in SST and chlorophyll-a gradients across bioregions, with two main breaks in SST separating the east and south-east overlap (SEO) bioregions from the south, south-west overlap (SWO) and west bioregions. In contrast, chlorophyll-a exhibited three major breaks with the east, SEO–south–SWO, and west clustering independently of each other. The RLQ analysis (a type of co-inertia analysis) which simultaneously ordinates 3-matrix datasets [i.e., (environment × site[R]), (species × site[L]) and (species × traits [Q])] showed that the higher SST gradient on the east and SEO promoted higher abundance and biomass of simultaneous hermaphrodites while higher chlorophyll-a gradients on the SWO and west coasts strongly promoted reproductive maturity at larger-sizes. The combined fourth-corner analyses showed that the modalities within the development trait domain responding to chlorophyll-a gradients primarily included filter feeders, sessile and swimming species and also species living on the infratidal zone. In addition, the reproduction trait domain showed higher sensitivity and association to differences in chlorophyll-a and SST gradients than development traits. Overall, SST and chlorophyll-a gradients influenced the distribution of the most dominant traits as indicated by shifts in community-weighted mean trait values across bioregions. This suggests the importance of habitat filtering on coastal species reproduction. A separate study evaluating the influence of large-scale biogeographic effects vs the micro-scale biogenic habitat structure offered by coralline seaweeds across 24 sites revealed some notable effects of both factors on the diversity and abundance of macroalgal epifauna. There was a notable biogeographic influence on epifauna, with the SEO recording the highest epifaunal species richness and abundance, followed by the south coast, then the SWO and lastly the west coast. In addition, the total biomass gradient of the corallines followed a similar trend. The epifauna however, showed no host-specificity, illustrating that epifauna may not be species–centric as commonly assumed, and the higher diversity of epifaunal diversity may well be simply because those corallines are the available habitat within the sampled part of the coastline. Lastly, macroinvertebrate trait distribution on the South African coastline confirms that the habitat, particularly the biotic filter (in this case chl-a) provides a templet upon which evolution forges species traits. However, since temperature is a proxy for nutrient availability (cold upwelling brings nutrients), then temperature drives chlorophyll-a. Subsequently this means the abiotic component indirectly drives trait distribution by influencing the biotic environment (chl-a). For epifauna species, also, the coralline diversity and composition can also be regarded as a biotic filter influencing the epifaunal abundances and composition across different bioregions. Moreover, since temperature is regarded as a conservative trait in seaweeds, temperature tolerance defines the biogeographical boundaries of seaweeds, therefore temperature may be indirectly affecting epifauna abundances through coralline species diversity and biomass. In summary, considering the deterministic processes governing ecosystem functioning and community assemblage, the mass ratio and limiting similarity hypotheses showed complementary effects. Different bioregions provided variable support for these two hypotheses, but overall, the mass ratio hypothesis (weighted by species biomass) received stronger support and may be more meaningful to the interpretation of ecosystem functioning and persistence within rocky shore systems. Lastly, although, the SWO showed some of the characteristics of a subtraction zone based on the relatively low abundance, diversity, and biomass measures. Nonetheless, there was evidence of high functional redundancy across all other four bioregions. This suggests that in the context of development and reproduction traits, the rocky shore ecosystem along the SA coastline may be functionally stable at this stage. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
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  • Date Issued: 2022-10-14

Genetic analysis and field application of a UV-tolerant strain of CrleGV for improved control of Thaumatotibia leucotreta

  • Authors: Bennett, Tahnee Tashia
  • Date: 2022-10-14
  • Subjects: Cryptophlebia leucotreta Biological control , Pests Integrated control , Biological pest control agents , Ultraviolet radiation , Oligonucleotides
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/362741 , vital:65358
  • Description: Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), also known as false codling moth (FCM), is indigenous to sub-Saharan Africa. Thaumatotibia leucotreta has been controlled through an integrated pest management (IPM) programme, which includes chemical control, sterile insect technique (SIT), cultural and biological control. As part of the biological control, a key component is the use of Cryptophlebia leucotreta granulovirus (CrleGV-SA). Currently, CryptogranTM, a commercial formulation of CrleGV, is the preferred product to use in South Africa for the control of T. leucotreta. The registration of the biopesticide Cryptogran (River bioscience, South Africa) was established after conducting extensive field trials with CrleGV-SA. One of the major factors affecting the baculovirus efficacy in the field is UV irradiation. A UV-tolerant Cryptophlebia leucotreta granulovirus (CrleGV-SA-C5) isolate was isolated after consecutive cycles of UV exposure. This UV-tolerant isolate is genetically distinct from the CrleGV-SA isolate. The CrleGV-SA-C5 isolate has the potential as a biological control agent. The control of T. leucotreta in South Africa could be improved by the development of novel isolates into new biopesticide formulations. To date, there has not been any field trials conducted on the CrleGV-SA-C5 isolate. Therefore, it is important to determine the biological and genetic stability of this isolate and to conduct field trials with CrleGV-SA- C5 to test the efficacy of the isolate before possible production into a biopesticide. A de novo assembly was conducted to reassemble the genome of CrleGV-SA-C5 which was followed by a sequence comparison with the CrleGV-SA genome. The identification of SNPs, led to the design of oligonucleotides flanking the regions where the SNPs were detected. Polymerase chain reaction amplification of the target regions was conducted using the oligonucleotides. After sequence comparison, seven SNPs were detected and PCR amplification was successful using the three oligonucleotides, Pif-2, HypoP and Lef-8/HP. To differentiate between CrleGV-SA-C5 and CrleGV-SA genomes and confirm the presence of the SNPs, two methods of screening were conducted. The first was the construction of six plasmids, the plasmids contained the targeted pif-2, HypoP, and the Lef-8/HP insert regions from both the CrleGV-SA-C5 and CrleGV-SA genome region where the SNPs were identified, followed by sequencing. The Five recombinant plasmids, pC5_Pif-2, pSA_Pif-2, pC5_HypoP, pSA_HypoP, and pC5_Lef-8/HP were successfully sequenced. No amplicon was obtained for one of the plasmids used as template (pSA_Lef-8/HP) and therefore the PCR product used for cloning was sequenced instead. Sequence alignment confirmed the presence of four of the five targeted SNPs in the genome of the CrleGV-SA-C5 isolate. However, of these only one SNP (UV_7) rendered a suitable marker for the differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates as the SNPs, UV_2, UV_3 and UV_5, were also present in the CrleGV- SA sequences. The second screening method was a quantitative polymerase chain reaction (qPCR) melt curve analysis to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. qPCR melt curve analysis was done using the CrleGV-SA-C5 and CrleGV-SA HypoP PCR products. This technique was unable to differentiate between the CrleGV-SA-C5 and CrleGV-SA isolates. However, this may be as a result of sequence data confirming that SNP UV_5 originally identified in the CrleGV-SA-C5 HypoP region was identical to the SNP at the same position in the CrleGV-SA HypoP region. Following the differentiation of the CrleGV-SA-C5 and CrleGV-SA isolates through two screening methods, the genetic integrity of the CrleGV-SA-C5 isolate after two virus bulk-ups was determined by PCR amplification of the target regions in the bulk-up virus followed by sequencing. Prior to virus bulk-up, surface dose bioassays were conducted on 4th instar larvae and LC50 and LC90 values of 4.01 x 106 OBs/ml and 8.75 x 109 OBs/ml respectively were obtained. The CrleGV-SA-C5 isolate was then bulked up in fourth instar T. leucotreta larvae using the LC90 value that was determined. Sequencing of the target regions from the CrleGV- SA-C5_BU2 (bulk-up 2) was conducted. Sequencing results confirmed the presence of the target SNPs in the CrleGV-SA-C5_BU2 genome. The UV-tolerance of the CrleGV-SA-C5 isolate in comparison to the CrleGV-SA isolate was evaluated by detached fruit bioassays under natural UV irradiation. Two detached fruit bioassays were set-up, a UV exposure and a non-UV exposure bioassay set-up. Three treatments were used for each bioassay set-up which were the viruses CrleGV-SA-C5 and CrleGV-SA and a ddH2O control. Statistical analysis indicated that there was no significant difference between the virus treatments in both the UV exposed detached fruit bioassay and the non-UV exposed detached fruit bioassay. This study is the second study to report on the de novo assembly of the CrleGV-SA-C5 and sequence comparison with the CrleGV-SA genome, and the first to report on the UV-tolerance of the CrleGV-SA-C5 isolate by detached fruit bioassays. Future work could involve further evaluation of intraspecific genetic variability in the CrleGV-SA-C5 isolate and to identify any additional SNPs present within the genome that can be used as suitable markers for differentiation between the CrleGV-SA-C5 and CrleGV-SA isolates. It was recognised that it is required to conduct further detached fruit bioassays and field trials, but with improved protocols, for the efficacy and UV-tolerance of the CrleGV-SA-C5 isolate to be conclusively determined. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2022
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  • Date Issued: 2022-10-14

Inadequate menstrual health management and human rights

  • Authors: Hartley, Gemma-Maé
  • Date: 2022-10-14
  • Subjects: Menstrual hygiene management , Human rights , Political philosophy , Transgression , Women Social conditions , Economic, social and cultural rights
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/422506 , vital:71953
  • Description: Various human rights bodies have suggested that Inadequate Menstrual Health Management (MHM) could contribute to violations of human rights or, at the very least, is connected to the fulfilment of human rights. Despite recognition of this, there has not been thorough analysis of whether inadequate MHM is a violation of human rights, particularly in political discussions on the philosophy of human rights. Using a liberal cosmopolitan framework, this thesis attempts to bridge this gap and, ultimately, to argue that inadequate MHM constitutes a violation of human rights. This assertion brings with it various complications due to the heavily contested nature of human rights, their correlative duties, and the requirements for a lack of fulfilment to be considered a violation. I address each complication in turn. I argue that the traditional approach to human rights violations fails to consider the various ways that human rights are violated in our contemporary, globalised world. I suggest that structural violations of human rights should not be ruled out, particularly when we consider severe poverty and its by-products. Ultimately, the question of inadequate MHM is concerned with the content of human rights. If inadequate MHM were a violation, it would be a violation of women’s socio-economic rights. However, both group rights and socio-economic rights are contested. This thesis therefore justifies these rights. Group-differentiated rights are argued to be necessary for substantive equality. This is particularly the case when we consider the various risks women face simply because they are women. Women therefore need special protections and provisions for their human rights to be fulfilled. Socio-economic rights are necessary for the well-being and dignity of individuals everywhere. We can justify them even if they are costly, vague, and demanding on states, as critics argue they are. Therefore, if we can accept socio-economic rights and women’s rights, we can argue that inadequate MHM is a structural violation of human rights. Thinking about inadequate MHM in this way means we can respond to it with a level of urgency. This has the potential to improve the well-being, development, and dignity of women. , Thesis (MA) -- Faculty of Humanities, Political and International Studies, 2023
  • Full Text:
  • Date Issued: 2022-10-14
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