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A study of why some physic concepts in the South African Physical Science curriculum are poorly understood in order to develop a targeted action-research intervention for Newton’s second law
- Authors: Cobbing, Kathleen Margaret
- Date: 2020
- Subjects: Physics -- Study and teaching (Secondary) -- South Africa , Physics -- Examinations, questions, etc. -- South Africa , Motion -- Study and teaching (Secondary) -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/146903 , vital:38575
- Description: Globally, many students show a poor understanding of concepts in high school physics and lack the necessary problem-solving skills that the course demands. The application of Newton’s second law was found to be particularly problematic through document analysis of South African examination feedback reports, as well as from an analysis of the physics examinations at a pair of well-resourced South African independent schools that follow the Independent Examination Board curriculum. Through an action-research approach, a resource for use by students was designed and modified to improve students’ understanding of this concept, while modelling problemsolving methods. The resource consisted of brief revision notes, worked examples and scaffolded exercises. The design of the resource was influenced by the theory of cognitive apprenticeship, cognitive load theory and conceptual change theory. One of the aims of the resource was to encourage students to translate between the different representations of a problem situation: symbolic, abstract, model and concrete. The impact of this resource was evaluated at a pair of schools using a mixed methods approach. This incorporated pre- and post-tests for a quantitative assessment, qualitative student evaluations and the analysis of examination scripts. There was an improvement from pre- to post-test for all four iterations of the intervention and these improvements were shown to be significant. The use of the resource led to an increase in the quality and quantity of diagrams drawn by students in subsequent assessments.
- Full Text:
- Authors: Cobbing, Kathleen Margaret
- Date: 2020
- Subjects: Physics -- Study and teaching (Secondary) -- South Africa , Physics -- Examinations, questions, etc. -- South Africa , Motion -- Study and teaching (Secondary) -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/146903 , vital:38575
- Description: Globally, many students show a poor understanding of concepts in high school physics and lack the necessary problem-solving skills that the course demands. The application of Newton’s second law was found to be particularly problematic through document analysis of South African examination feedback reports, as well as from an analysis of the physics examinations at a pair of well-resourced South African independent schools that follow the Independent Examination Board curriculum. Through an action-research approach, a resource for use by students was designed and modified to improve students’ understanding of this concept, while modelling problemsolving methods. The resource consisted of brief revision notes, worked examples and scaffolded exercises. The design of the resource was influenced by the theory of cognitive apprenticeship, cognitive load theory and conceptual change theory. One of the aims of the resource was to encourage students to translate between the different representations of a problem situation: symbolic, abstract, model and concrete. The impact of this resource was evaluated at a pair of schools using a mixed methods approach. This incorporated pre- and post-tests for a quantitative assessment, qualitative student evaluations and the analysis of examination scripts. There was an improvement from pre- to post-test for all four iterations of the intervention and these improvements were shown to be significant. The use of the resource led to an increase in the quality and quantity of diagrams drawn by students in subsequent assessments.
- Full Text:
A study on certain factors that may affect the economic viability of backgrounding beef weaner calves on pastures in the Southern Cape area of South Africa
- Authors: Terblanche, Ian
- Date: 2020
- Subjects: Calves -- Weaning -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/47623 , vital:40259
- Description: The backgrounding of beef weaner calves from pastures has the potential to be developed as an intensive beef enterprise that can increase the income of smaller farms, given that these farms have the ability to produce good quality pastures. This study was conducted to verify the inputs that impact on the viability of pasture backgrounding systems in an attempt to provide beef producers with better information for decision making. The scientific research was conducted with the registered Kromme Rhee Bonsmara herd at the Kromme Rhee research farm of the Western Cape Department of Agriculture. The farm is situated at 18º50’E and 33º51’S in the Stellenbosch area and has an altitude of 177 m above sea level. The area is situated in the winter rainfall region of the Western Cape with an annual rainfall of 670 mm. The average summer temperature ranges between 15-35 ºC and winter temperature between 10-17 ºC. The aim of this study was to develop growth curves representing the growth of Bonsmara animals for use by beef producers in predicting future live weight of animals in a pasture backgrounding system. Dry matter (DM) intake was measured at various live weight stages in order to determine whether a prediction model could be established to represent the DM intake of growing Bonsmara cattle on pastures. Results were used as inputs to determine whether backgrounding on pastures was economically viable. Animals were weighed at monthly intervals. Weighings commenced from birth and continued for a period of 797 days, repeated with two production year groups. One group consisted of 18 heifers and 12 bulls that were weighed from birth till an average age of 759 days. The other group consisted of four heifers and seven bulls and was weighed from birth untill an average age of 892 days. Roughage supplementation was done with lucerne hay in periods of pasture shortfalls, while a protein and energy lick were supplied continuously. A feeding trial with 10 weaned heifers and 10 bull calves of the same year group was conducted to determine the average feed intake per individual animal over a thirteen-month period that commenced after weaning. Two groups of five Bonsmara bull calves and two groups of five Bonsmara heifers were grouped according to age and gender. The feed intake of the growing calves was recorded for different live weight categories. The animals received lucerne (Medicago sativa) hay on an ad lib basis, while a concentrate supplement was supplied at 2 kg per animal per day up until live weights of 350 kg for heifers and 380 kg for bulls was achieved. The lucerne based diet was formulated to simulate a diet for growing animals on pasture with additional supplementation. Group feed intake values of the four groups of animals were measured at about 20-day intervals over the trial period of 369 days. The feed waste was dried and weighed back to calculate a waste percentage to be used as a correction factor. The Gompertz growth function was used to develop growth curves for male and female Bonsmara animals. Results indicated a significant difference between the mature weight of males and females (P <0.05). In both year groups the nonlinear Gompertz growth model predicted heavier mature weight for males compared to females. Mature weights of bulls were respectively 44.4% and 68.5% higher than that of heifers over the two year period. Days at maximum growth occurred later for males than for females (P <0.05) and the maturing rate of males and females did not differ significantly. Individual average feed intakes were calculated from the group fed animals over the duration of the rearing period. The data revealed that feed intake for bulls can be predicted by the linear model, DMI= 0.16531 + 0.0235306 x live weight (P ≤0.001; R 2 = 78.25). The feed intake of heifers can be predicted by the linear model, DMI= -1.41991 + 0.0283891 x live weight (P ≤0.001; R 2= 76.25). Analysis of variance detected no difference between the percentage feed intake of heifers (2.46%) and bulls (2.40%), over the experimental period. Prices of different live weight groupings were analysed over seven years to establish whether cyclical price trends can be observed across years and seasonal price trends within years. Within years prices were found to differ between months. For all calf weight groups, the lowest prices occurred in the months of March, April, May, June and July which showed price indices significantly different (P <0.05) from indices of the months of October, November and December when highest prices occurred, confirming seasonality in weaner calf prices. Price indices were developed for use as an input in the economic viability assessment. A brief literature review on the production and quality of four common pastures in the Southern Cape was done to gather information for compiling pasture budgets for use in determining the economic viability of pasture backgrounding. The economic viability of backgrounding on pastures was evaluated on a gross margin level and illustrated for three pasture systems namely irrigated oats as a winter pasture, irrigated lucerne as a spring pasture and dryland P. clandestinum /E. plana /mixed grass also as a low-cost spring pasture. All three pasture systems showed a positive economic viability for the decision parameters used in the illustration. The gross margin of backgrounding on the oats pasture system was more sensitive to a small decrease in the predicted price or the predicted live weight and therefore a riskier option than backgrounding on the other two systems. Outputs from the gross margin analyses were used in partial budgeting to illustrate a robust decision support framework that beef farmers can use for making decisions whether to sell weaners straight after weaning as opposed to selling after a period of backgrounding on pastures. Overall results indicate that backgrounding of calves on pastures has the potential to be a viable beef enterprise on smaller farms in the region. Keywords: beef production; Gompertz growth curves, feed intake; pasture backgrounding; gross margin; partial budgets.
- Full Text:
- Authors: Terblanche, Ian
- Date: 2020
- Subjects: Calves -- Weaning -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/47623 , vital:40259
- Description: The backgrounding of beef weaner calves from pastures has the potential to be developed as an intensive beef enterprise that can increase the income of smaller farms, given that these farms have the ability to produce good quality pastures. This study was conducted to verify the inputs that impact on the viability of pasture backgrounding systems in an attempt to provide beef producers with better information for decision making. The scientific research was conducted with the registered Kromme Rhee Bonsmara herd at the Kromme Rhee research farm of the Western Cape Department of Agriculture. The farm is situated at 18º50’E and 33º51’S in the Stellenbosch area and has an altitude of 177 m above sea level. The area is situated in the winter rainfall region of the Western Cape with an annual rainfall of 670 mm. The average summer temperature ranges between 15-35 ºC and winter temperature between 10-17 ºC. The aim of this study was to develop growth curves representing the growth of Bonsmara animals for use by beef producers in predicting future live weight of animals in a pasture backgrounding system. Dry matter (DM) intake was measured at various live weight stages in order to determine whether a prediction model could be established to represent the DM intake of growing Bonsmara cattle on pastures. Results were used as inputs to determine whether backgrounding on pastures was economically viable. Animals were weighed at monthly intervals. Weighings commenced from birth and continued for a period of 797 days, repeated with two production year groups. One group consisted of 18 heifers and 12 bulls that were weighed from birth till an average age of 759 days. The other group consisted of four heifers and seven bulls and was weighed from birth untill an average age of 892 days. Roughage supplementation was done with lucerne hay in periods of pasture shortfalls, while a protein and energy lick were supplied continuously. A feeding trial with 10 weaned heifers and 10 bull calves of the same year group was conducted to determine the average feed intake per individual animal over a thirteen-month period that commenced after weaning. Two groups of five Bonsmara bull calves and two groups of five Bonsmara heifers were grouped according to age and gender. The feed intake of the growing calves was recorded for different live weight categories. The animals received lucerne (Medicago sativa) hay on an ad lib basis, while a concentrate supplement was supplied at 2 kg per animal per day up until live weights of 350 kg for heifers and 380 kg for bulls was achieved. The lucerne based diet was formulated to simulate a diet for growing animals on pasture with additional supplementation. Group feed intake values of the four groups of animals were measured at about 20-day intervals over the trial period of 369 days. The feed waste was dried and weighed back to calculate a waste percentage to be used as a correction factor. The Gompertz growth function was used to develop growth curves for male and female Bonsmara animals. Results indicated a significant difference between the mature weight of males and females (P <0.05). In both year groups the nonlinear Gompertz growth model predicted heavier mature weight for males compared to females. Mature weights of bulls were respectively 44.4% and 68.5% higher than that of heifers over the two year period. Days at maximum growth occurred later for males than for females (P <0.05) and the maturing rate of males and females did not differ significantly. Individual average feed intakes were calculated from the group fed animals over the duration of the rearing period. The data revealed that feed intake for bulls can be predicted by the linear model, DMI= 0.16531 + 0.0235306 x live weight (P ≤0.001; R 2 = 78.25). The feed intake of heifers can be predicted by the linear model, DMI= -1.41991 + 0.0283891 x live weight (P ≤0.001; R 2= 76.25). Analysis of variance detected no difference between the percentage feed intake of heifers (2.46%) and bulls (2.40%), over the experimental period. Prices of different live weight groupings were analysed over seven years to establish whether cyclical price trends can be observed across years and seasonal price trends within years. Within years prices were found to differ between months. For all calf weight groups, the lowest prices occurred in the months of March, April, May, June and July which showed price indices significantly different (P <0.05) from indices of the months of October, November and December when highest prices occurred, confirming seasonality in weaner calf prices. Price indices were developed for use as an input in the economic viability assessment. A brief literature review on the production and quality of four common pastures in the Southern Cape was done to gather information for compiling pasture budgets for use in determining the economic viability of pasture backgrounding. The economic viability of backgrounding on pastures was evaluated on a gross margin level and illustrated for three pasture systems namely irrigated oats as a winter pasture, irrigated lucerne as a spring pasture and dryland P. clandestinum /E. plana /mixed grass also as a low-cost spring pasture. All three pasture systems showed a positive economic viability for the decision parameters used in the illustration. The gross margin of backgrounding on the oats pasture system was more sensitive to a small decrease in the predicted price or the predicted live weight and therefore a riskier option than backgrounding on the other two systems. Outputs from the gross margin analyses were used in partial budgeting to illustrate a robust decision support framework that beef farmers can use for making decisions whether to sell weaners straight after weaning as opposed to selling after a period of backgrounding on pastures. Overall results indicate that backgrounding of calves on pastures has the potential to be a viable beef enterprise on smaller farms in the region. Keywords: beef production; Gompertz growth curves, feed intake; pasture backgrounding; gross margin; partial budgets.
- Full Text:
A study on reporting and learning in three natural resource management programmes in South Africa
- Authors: Mushwana, Vhutshilo Mudau
- Date: 2020
- Subjects: Natural resources -- Management -- South Africa -- Case studies , Working for Water Programme , South African National Parks , Kruger to Canyon , Association for Water and Rural Development (South Africa) , RESILiM-Olifants Programme , Active learning -- South Africa , Environmental reporting , Environmental reporting -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167586 , vital:41494
- Description: This is a case study that focuses on three Natural Resource Management programmes, namely: the Department of Environmental Affair’s Working for Water Programme, the Kruger to Canyon SANParks Biodiversity Social Projects as well as AWARD’s programme for Resilience in the Limpopo-Olifants Basin. All three programmes are being implemented in the Limpopo and Mpumalanga Provinces of South Africa. As a monitoring and evaluation officer at AWARD, I was part of the team that developed a strategy to enable learning through monitoring, evaluation and reporting, and this sparked my interest in understanding how other programmes might be approaching this. The focus of the study is on the role of reporting, as part of programme monitoring and evaluation, as a means to support learning of both programme implementers and organisations. An in-depth description of each case has been provided to enable an understanding of the overall reporting system, how reporting may play a role in supporting individual and organisational learning, and what factors enable or constrain learning in association with reporting. The research was descriptive and interpretive as the first phase of a possible extended study engaging organisations in exploring how to strengthen reporting for learning. The participants and organisations were sampled using both purposive and convenience sampling. Data was collected through 17 key informant interviews; observations during two learning events; and, the collection and review of numerous documents (guides, reports, templates etc.). The data was analysed through qualitative content analysis using two frameworks: Argyris’ three loops of learning (1974;1978) and the Cultural-Historical Activity Theory (CHAT) lens (Engeström, 1987). The former was useful for bounding the types of learning to identify, and the latter for surfacing contradictions that can be explored in organisational development processes. Through the analysis of the data and literature, the following insights were gained: All three programmes have been ‘thinking’ about learning, but only in the case of AWARD was reporting associated with learning; in all three programmes, additional spaces have been designed to facilitate learning. Although programmes might not necessarily focus on reporting for learning, their reports do indicate a potential for facilitating reflection and thus learning. The organisational culture in government-based reporting systems is, however, strongly geared to performance management, accounting for resources spent, meeting targets and eliminating mistakes. Reports are used to guide planning, to account to the funder and to release further funding.. In this context only single and double loop learning is in evidence. Programme participants did raise ‘triple loop’ questions about whether the programme or system overall was working, but there did not seem to be space for such questions, in the reporting or the learning events, and there was no evidence that they were addressed. In the case of AWARD, spaces were created through reporting to encourage learning. This worked sometimes to enable learning but not always due to, for example, time constraints and competing responsibilities. There are certain aspects to consider when designing reporting that seem to support learning (see below). The process of using reporting for learning takes time and organisations might not get this right the first time around. Reflection opportunities are only experienced as enabling if participants have the space and power to act on the reflections, or see others acting on them to address issues, otherwise they get frustrated. Steps that could assist programmes in improving reporting to enable learning are: Adding to reporting templates a space for reflections to ensure that while the programme reports on the quantitative data needed for accountability purposes, it also creates additional space (without unduly increasing reporting responsibilities) for implementers’ learning. Encouraging discussion about ‘mistakes’ such as failures to meet targets, why they occur, and what we can learn from them. Allowing programme implementers to give feedback on their reporting challenges and take measures to support them, e.g. make adjustments to templates. Understanding the programme’s definition of learning, and the diverse learning needs that may be involved, which can contribute to a working strategy that the organisation can build on when initiating learning spaces. When learning events are organised, taking the inputs of participants seriously and developing ways in which these could be taken further into actions from which further learning can stem; reflecting on and raising issues without an opportunity for action is frustrating. The process of enabling reporting for learning takes time and organisations might not get it right the first time around (trial and error) and a strategy that worked for one organisation might not necessarily work for the next. When designing a learning strategy as part of a monitoring, evaluation and reporting framework, it is therefore important to consider the needs of the organisation and to work with implementers to develop and refine this over time. The thesis concludes with comments on the limitations of the study, the methodology and the analytical frameworks used, and finally, provides recommendations for further research.
- Full Text:
- Authors: Mushwana, Vhutshilo Mudau
- Date: 2020
- Subjects: Natural resources -- Management -- South Africa -- Case studies , Working for Water Programme , South African National Parks , Kruger to Canyon , Association for Water and Rural Development (South Africa) , RESILiM-Olifants Programme , Active learning -- South Africa , Environmental reporting , Environmental reporting -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/167586 , vital:41494
- Description: This is a case study that focuses on three Natural Resource Management programmes, namely: the Department of Environmental Affair’s Working for Water Programme, the Kruger to Canyon SANParks Biodiversity Social Projects as well as AWARD’s programme for Resilience in the Limpopo-Olifants Basin. All three programmes are being implemented in the Limpopo and Mpumalanga Provinces of South Africa. As a monitoring and evaluation officer at AWARD, I was part of the team that developed a strategy to enable learning through monitoring, evaluation and reporting, and this sparked my interest in understanding how other programmes might be approaching this. The focus of the study is on the role of reporting, as part of programme monitoring and evaluation, as a means to support learning of both programme implementers and organisations. An in-depth description of each case has been provided to enable an understanding of the overall reporting system, how reporting may play a role in supporting individual and organisational learning, and what factors enable or constrain learning in association with reporting. The research was descriptive and interpretive as the first phase of a possible extended study engaging organisations in exploring how to strengthen reporting for learning. The participants and organisations were sampled using both purposive and convenience sampling. Data was collected through 17 key informant interviews; observations during two learning events; and, the collection and review of numerous documents (guides, reports, templates etc.). The data was analysed through qualitative content analysis using two frameworks: Argyris’ three loops of learning (1974;1978) and the Cultural-Historical Activity Theory (CHAT) lens (Engeström, 1987). The former was useful for bounding the types of learning to identify, and the latter for surfacing contradictions that can be explored in organisational development processes. Through the analysis of the data and literature, the following insights were gained: All three programmes have been ‘thinking’ about learning, but only in the case of AWARD was reporting associated with learning; in all three programmes, additional spaces have been designed to facilitate learning. Although programmes might not necessarily focus on reporting for learning, their reports do indicate a potential for facilitating reflection and thus learning. The organisational culture in government-based reporting systems is, however, strongly geared to performance management, accounting for resources spent, meeting targets and eliminating mistakes. Reports are used to guide planning, to account to the funder and to release further funding.. In this context only single and double loop learning is in evidence. Programme participants did raise ‘triple loop’ questions about whether the programme or system overall was working, but there did not seem to be space for such questions, in the reporting or the learning events, and there was no evidence that they were addressed. In the case of AWARD, spaces were created through reporting to encourage learning. This worked sometimes to enable learning but not always due to, for example, time constraints and competing responsibilities. There are certain aspects to consider when designing reporting that seem to support learning (see below). The process of using reporting for learning takes time and organisations might not get this right the first time around. Reflection opportunities are only experienced as enabling if participants have the space and power to act on the reflections, or see others acting on them to address issues, otherwise they get frustrated. Steps that could assist programmes in improving reporting to enable learning are: Adding to reporting templates a space for reflections to ensure that while the programme reports on the quantitative data needed for accountability purposes, it also creates additional space (without unduly increasing reporting responsibilities) for implementers’ learning. Encouraging discussion about ‘mistakes’ such as failures to meet targets, why they occur, and what we can learn from them. Allowing programme implementers to give feedback on their reporting challenges and take measures to support them, e.g. make adjustments to templates. Understanding the programme’s definition of learning, and the diverse learning needs that may be involved, which can contribute to a working strategy that the organisation can build on when initiating learning spaces. When learning events are organised, taking the inputs of participants seriously and developing ways in which these could be taken further into actions from which further learning can stem; reflecting on and raising issues without an opportunity for action is frustrating. The process of enabling reporting for learning takes time and organisations might not get it right the first time around (trial and error) and a strategy that worked for one organisation might not necessarily work for the next. When designing a learning strategy as part of a monitoring, evaluation and reporting framework, it is therefore important to consider the needs of the organisation and to work with implementers to develop and refine this over time. The thesis concludes with comments on the limitations of the study, the methodology and the analytical frameworks used, and finally, provides recommendations for further research.
- Full Text:
A systematic review of the efficacy of internet-based interventions for depression and anxiety disorders: the possibilities and limitations for feasibility within South Africa
- Authors: Sealy-Fisher, Kay Tibeta
- Date: 2020
- Subjects: Depression, Mental -- Treatment -- South Africa , Anxiety disorders -- Treatment -- South Africa , Internet in psychotherapy -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144632 , vital:38364
- Description: Technological advances may alleviate the burden on South Africa’s mental healthcare system. This study is a systematic review of literature that assesses the efficacy of high quality online interventions for depression and anxiety, and that compares the reviewed studies’ characteristics to the South African context to assist in future developments of online interventions for depression and anxiety within South Africa. This was achieved through using a 2010 systematic review of Griffiths, Farrer, and Christensen as point of departure. This research had two aims: to provide an updated systematic review of the literature reporting on the efficacy of internet-based interventions for depression and anxiety disorders; and to evaluate the possibilities and limitations for the feasibility of implementing internet-based interventions for depression and anxiety disorders in the South African context. Databases accessed were PubMed, PsycINFO, and Cochrane Central Register of Controlled Trials. Included studies must: (i) report on one or more internet-based intervention, (ii) target depression or anxiety or both, (iii) report the effect size or provide enough information to calculate it, (iv) report a measure of symptoms outcome, (v) be a Randomised Controlled Trial, (vi) include a control group that received no active intervention, (vii) be published and peer-reviewed, (viii) have been published after January 2010. The search yielded 2999 potential studies of which 20 full texts were reviewed. Of these, 75% (n=15) of the studies report effect sizes above 0.20, and 25% (n=5) of the studies report effect sizes above 0.80. Themes emergent from literature and included studies distinguished effective from non-effective studies included the use of cognitive behavioural therapy, therapist input and reminders to engage with the intervention, and duration of over 6 weeks. Attrition rates did not differ between experimental and control groups. Sample characteristics between the reviewed interventions and South Africa’s population were found to be different and is discussed. Unfortunately, 37 potential studies could not be accessed and thus not included, although several attempts were made. The majority of studies had effect sizes equal to that of face-to-face therapeutic interventions. Implications of application in South Africa’s context with limited technological familiarity, insufficiency of professionally trained therapists, poor literacy, and high costs of internet data are discussed. It is concluded that with appropriate adaptation, online internet interventions for depression and anxiety would be beneficial to South Africa’s people and assist in lowering the country’s burden of mental health disorders.
- Full Text:
- Authors: Sealy-Fisher, Kay Tibeta
- Date: 2020
- Subjects: Depression, Mental -- Treatment -- South Africa , Anxiety disorders -- Treatment -- South Africa , Internet in psychotherapy -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144632 , vital:38364
- Description: Technological advances may alleviate the burden on South Africa’s mental healthcare system. This study is a systematic review of literature that assesses the efficacy of high quality online interventions for depression and anxiety, and that compares the reviewed studies’ characteristics to the South African context to assist in future developments of online interventions for depression and anxiety within South Africa. This was achieved through using a 2010 systematic review of Griffiths, Farrer, and Christensen as point of departure. This research had two aims: to provide an updated systematic review of the literature reporting on the efficacy of internet-based interventions for depression and anxiety disorders; and to evaluate the possibilities and limitations for the feasibility of implementing internet-based interventions for depression and anxiety disorders in the South African context. Databases accessed were PubMed, PsycINFO, and Cochrane Central Register of Controlled Trials. Included studies must: (i) report on one or more internet-based intervention, (ii) target depression or anxiety or both, (iii) report the effect size or provide enough information to calculate it, (iv) report a measure of symptoms outcome, (v) be a Randomised Controlled Trial, (vi) include a control group that received no active intervention, (vii) be published and peer-reviewed, (viii) have been published after January 2010. The search yielded 2999 potential studies of which 20 full texts were reviewed. Of these, 75% (n=15) of the studies report effect sizes above 0.20, and 25% (n=5) of the studies report effect sizes above 0.80. Themes emergent from literature and included studies distinguished effective from non-effective studies included the use of cognitive behavioural therapy, therapist input and reminders to engage with the intervention, and duration of over 6 weeks. Attrition rates did not differ between experimental and control groups. Sample characteristics between the reviewed interventions and South Africa’s population were found to be different and is discussed. Unfortunately, 37 potential studies could not be accessed and thus not included, although several attempts were made. The majority of studies had effect sizes equal to that of face-to-face therapeutic interventions. Implications of application in South Africa’s context with limited technological familiarity, insufficiency of professionally trained therapists, poor literacy, and high costs of internet data are discussed. It is concluded that with appropriate adaptation, online internet interventions for depression and anxiety would be beneficial to South Africa’s people and assist in lowering the country’s burden of mental health disorders.
- Full Text:
A theory-based approach to evaluating a Continuing Teacher Professional Development Programme aimed at strengthening environment and sustainability education
- Authors: Songqwaru, Nonyameko Zintle
- Date: 2020
- Subjects: Fundisa for Change , Environmental education -- South Africa , Teachers -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/145267 , vital:38423
- Description: This study uses a theory-based approach to evaluate the Fundisa for Change training programme, a continuing teacher professional development programme aimed at strengthening environment and sustainability education. The aim of the study was to surface assumptions that underpin the design and implementation of the Fundisa for Change training programme. The Fundisa for Change Teacher Education programme is a national collaborative programme that is implemented in all the nine provinces of South Africa. The study reports on the implementation of the programme in five provinces. The study aimed to surface the Fundisa for Change training programme’s implementation theory and programme theory as these affect programme delivery. The Fundisa for Change training programme was implemented in diverse contexts by different facilitators to different participants. To determine how training programme outcomes were achieved, use was made of context-mechanism-outcome (CMO) configurations for each site where the programme was implemented. Data used to construct CMO configurations was generated through document analysis of Fundisa for Change documents, interviews with stakeholders and participants, as well as observations of programme implementation at five sites. There were three phases to data analysis: content analysis of Fundisa for Change documents, content analysis of observation transcripts and use of the CMO configuration, an analytical tool used in realist evaluation. An initial CMO configuration was constructed prior to observing implementation of the programme and a refined CMO configuration for the Fundisa for Change training programme was constructed based on similarities between the CMO configurations constructed for each of the five sites under study. The partnership model of the Fundisa for Change training programme brought diverse expertise and resources (material, cognitive, social and emotional) which were conducive to the achievement of programme outcomes. The programme’s action context (structure, culture, agency and relations) contributed to the achievement of programme outcomes by participants. Participants’ subject content knowledge, teaching practice and assessment practice was enhanced through attending the Fundisa for Change training. On-course tasks were mediated during training and this created opportunities for participants to discuss and reflect on current practice in ways that could lead to a change in practice. In evaluating professional development programmes, an elaborated definition of context in terms of structure, culture, agency and relations enables a comprehensive exploration of potential programme mechanisms that can be activated when programmes are implemented. It is also important to disaggregate resources and reasons when identifying mechanisms as this assists with differentiating between context and mechanisms. The study offers insights into the professional learning of teachers grappling with new content and pedagogical content knowledges related to environment in the context of recent curriculum changes where the South African national school curriculum has come into focus. Environmental education programmes in South Africa have implicitly used a realist approach. This study offers the first substantive professional learning evaluation that develops this approach explicitly using Theory of Change and Realist Evaluation in combination.
- Full Text:
- Authors: Songqwaru, Nonyameko Zintle
- Date: 2020
- Subjects: Fundisa for Change , Environmental education -- South Africa , Teachers -- Training of -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/145267 , vital:38423
- Description: This study uses a theory-based approach to evaluate the Fundisa for Change training programme, a continuing teacher professional development programme aimed at strengthening environment and sustainability education. The aim of the study was to surface assumptions that underpin the design and implementation of the Fundisa for Change training programme. The Fundisa for Change Teacher Education programme is a national collaborative programme that is implemented in all the nine provinces of South Africa. The study reports on the implementation of the programme in five provinces. The study aimed to surface the Fundisa for Change training programme’s implementation theory and programme theory as these affect programme delivery. The Fundisa for Change training programme was implemented in diverse contexts by different facilitators to different participants. To determine how training programme outcomes were achieved, use was made of context-mechanism-outcome (CMO) configurations for each site where the programme was implemented. Data used to construct CMO configurations was generated through document analysis of Fundisa for Change documents, interviews with stakeholders and participants, as well as observations of programme implementation at five sites. There were three phases to data analysis: content analysis of Fundisa for Change documents, content analysis of observation transcripts and use of the CMO configuration, an analytical tool used in realist evaluation. An initial CMO configuration was constructed prior to observing implementation of the programme and a refined CMO configuration for the Fundisa for Change training programme was constructed based on similarities between the CMO configurations constructed for each of the five sites under study. The partnership model of the Fundisa for Change training programme brought diverse expertise and resources (material, cognitive, social and emotional) which were conducive to the achievement of programme outcomes. The programme’s action context (structure, culture, agency and relations) contributed to the achievement of programme outcomes by participants. Participants’ subject content knowledge, teaching practice and assessment practice was enhanced through attending the Fundisa for Change training. On-course tasks were mediated during training and this created opportunities for participants to discuss and reflect on current practice in ways that could lead to a change in practice. In evaluating professional development programmes, an elaborated definition of context in terms of structure, culture, agency and relations enables a comprehensive exploration of potential programme mechanisms that can be activated when programmes are implemented. It is also important to disaggregate resources and reasons when identifying mechanisms as this assists with differentiating between context and mechanisms. The study offers insights into the professional learning of teachers grappling with new content and pedagogical content knowledges related to environment in the context of recent curriculum changes where the South African national school curriculum has come into focus. Environmental education programmes in South Africa have implicitly used a realist approach. This study offers the first substantive professional learning evaluation that develops this approach explicitly using Theory of Change and Realist Evaluation in combination.
- Full Text:
A transportation management framework for the Polokwane local municipality during Zion Christian Church (ZCC) Easter weekend pilgrimage
- Authors: Mathebula, Andrew Mabila
- Date: 2020
- Subjects: Transportation -- Management , Urban transportation -- Planning , Urban transportation -- Management , Christian pilgrims and pilgrimages
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/46152 , vital:39509
- Description: The study investigated the impact of the high volume of vehicular traffic on pilgrims and the community during the Zion Christian Church (ZCC) Easter weekend pilgrimage. The researcher adopted an interpretivist research philosophy, and thus attempted to understand policy, planning, and management of the ZCC Easter pilgrimage through meanings that municipal officials assign to them. The study employed the action research approach by collaborating with the Polokwane Local Municipality (PLM) with a view to evolving lasting solutions to traffic congestion during the Easter weekend. The researchers used the seven-step model proposed by Van Tonder and Dietrichsen (Van Tonder and Dietrichsen, 2008). The justification of the model is that it is aligned with the action research model of Organisational Development (OD). It requires that a diagnosis process should be collaborative and participative towards offering solutions to organisational challenges as opposed to imposing a unilateral theoretical generated solution. This model also fits the ontological stance of the researchers which assumes that reality is co-constructed through engagement with other stakeholders. The researcher conducted semi-structured individual and focus groups discussion (FGD) using openended guides. The data from the informants were collected until a point of saturation. In addition to facilitation FGD discussion, the researcher made his own personal reflection of the participatory action research (PAR). A content analysis method was used to synthesise the qualitative data. The contents were extracted from transcribed interviews. The researcher carefully reviewed the notes several times and coded the notes independently. After that, the researcher coded the codes with each other for any potential contradiction. These codes were converted into themes and sub-themes. The qualitative content analysis process, led by the researcher, was both inductive and deductive. Prior to the inductive process, the researcher listened carefully to the audio recordings transcriptions to get a general understanding of participants’ experiences. The findings indicate that the South African transportation planning approach is ossified and divorced from reality. There is a lacuna to address peak traffic challenges during the Easter weekend and the festive season. It is notable that the government-led seasonal road safety campaigns such as ‘Arrive Alive’ are curiously inadequate to address peak traffic and road accidents challenges in South Africa during the ZCC Easter pilgrimage. The transportation management framework for the PLM as well as a peak traffic standard were developed as part of the study recommendations. These recommendations augur a shift to transport planning in South Africa.
- Full Text:
- Authors: Mathebula, Andrew Mabila
- Date: 2020
- Subjects: Transportation -- Management , Urban transportation -- Planning , Urban transportation -- Management , Christian pilgrims and pilgrimages
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/46152 , vital:39509
- Description: The study investigated the impact of the high volume of vehicular traffic on pilgrims and the community during the Zion Christian Church (ZCC) Easter weekend pilgrimage. The researcher adopted an interpretivist research philosophy, and thus attempted to understand policy, planning, and management of the ZCC Easter pilgrimage through meanings that municipal officials assign to them. The study employed the action research approach by collaborating with the Polokwane Local Municipality (PLM) with a view to evolving lasting solutions to traffic congestion during the Easter weekend. The researchers used the seven-step model proposed by Van Tonder and Dietrichsen (Van Tonder and Dietrichsen, 2008). The justification of the model is that it is aligned with the action research model of Organisational Development (OD). It requires that a diagnosis process should be collaborative and participative towards offering solutions to organisational challenges as opposed to imposing a unilateral theoretical generated solution. This model also fits the ontological stance of the researchers which assumes that reality is co-constructed through engagement with other stakeholders. The researcher conducted semi-structured individual and focus groups discussion (FGD) using openended guides. The data from the informants were collected until a point of saturation. In addition to facilitation FGD discussion, the researcher made his own personal reflection of the participatory action research (PAR). A content analysis method was used to synthesise the qualitative data. The contents were extracted from transcribed interviews. The researcher carefully reviewed the notes several times and coded the notes independently. After that, the researcher coded the codes with each other for any potential contradiction. These codes were converted into themes and sub-themes. The qualitative content analysis process, led by the researcher, was both inductive and deductive. Prior to the inductive process, the researcher listened carefully to the audio recordings transcriptions to get a general understanding of participants’ experiences. The findings indicate that the South African transportation planning approach is ossified and divorced from reality. There is a lacuna to address peak traffic challenges during the Easter weekend and the festive season. It is notable that the government-led seasonal road safety campaigns such as ‘Arrive Alive’ are curiously inadequate to address peak traffic and road accidents challenges in South Africa during the ZCC Easter pilgrimage. The transportation management framework for the PLM as well as a peak traffic standard were developed as part of the study recommendations. These recommendations augur a shift to transport planning in South Africa.
- Full Text:
A tribute to you
- Ndlebe-September, Thobeka Veronica
- Authors: Ndlebe-September, Thobeka Veronica
- Date: 2020
- Subjects: South African fiction (English) -- 21st century , South African fiction (English) -- History and criticism , Short stories, South African (English) -- 21st century , Xhosa fiction -- 21st century , Xhosa fiction -- History and criticism , Short stories, Xhosa -- 21st century , Diaries -- Authorship
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144989 , vital:38398
- Description: My collection of short stories reflects my interest in narrative biblical fiction, allegorical stories about people and nature that resonate with our daily lives. I have been greatly influenced by writers such as Joel Matlou, Flannery O’Connor, Barry Gifford, Miriam Tladi and Leah Harris amongst others. I have also been captivated by fairy tales and folk tales, and also the work of isiXhosa writers such as S. E. K. Mqhayi, Madiponi Masenya, and Hulisani Ramantswana. I have discovered that I can borrow certain styles and forms of writing to enhance my own stories which are situated within ‘local’ contexts such as education, poverty, employment, the body, life and death.
- Full Text:
- Authors: Ndlebe-September, Thobeka Veronica
- Date: 2020
- Subjects: South African fiction (English) -- 21st century , South African fiction (English) -- History and criticism , Short stories, South African (English) -- 21st century , Xhosa fiction -- 21st century , Xhosa fiction -- History and criticism , Short stories, Xhosa -- 21st century , Diaries -- Authorship
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/144989 , vital:38398
- Description: My collection of short stories reflects my interest in narrative biblical fiction, allegorical stories about people and nature that resonate with our daily lives. I have been greatly influenced by writers such as Joel Matlou, Flannery O’Connor, Barry Gifford, Miriam Tladi and Leah Harris amongst others. I have also been captivated by fairy tales and folk tales, and also the work of isiXhosa writers such as S. E. K. Mqhayi, Madiponi Masenya, and Hulisani Ramantswana. I have discovered that I can borrow certain styles and forms of writing to enhance my own stories which are situated within ‘local’ contexts such as education, poverty, employment, the body, life and death.
- Full Text:
A vision based multirotor aircraft for use in the security industry
- Authors: Nelson, Benjamin David
- Date: 2020
- Subjects: Drone aircraft -- South Africa , Mechatronics -- Research
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/46816 , vital:39664
- Description: This research consisted of developing a vision based multirotor aircraft that could be used in the security industry. A second-hand aircraft was purchased and modified. The aircraft made use of a Pixhawk flight controller and a Odroid XU4 companion computer, which resulted in the computer injecting commands into the flight controller. Robot Operating System was installed and used on the companion computer to integrate the vision system and the aircraft. The vision system was designed to help develop a landing system where the aircraft would land on an ArUco marker. The vision system also allowed the aircraft to detect and follow humans. A Software in the Loop (SITL) was run alongside Gazebo, allowing the developed landing system and the human detecting system to be simulated and tested. The developed landing system was implemented on the aircraft, where the developed landing system was tested and compared to the aircraft’s current GPS based landing system. The developed landing system obtained a better overall accuracy , while also taking longer to land the aircraft compared to the GPS based landing system. There were also numerous manual and autonomous test flights implemented on the aircraft.
- Full Text:
- Authors: Nelson, Benjamin David
- Date: 2020
- Subjects: Drone aircraft -- South Africa , Mechatronics -- Research
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/46816 , vital:39664
- Description: This research consisted of developing a vision based multirotor aircraft that could be used in the security industry. A second-hand aircraft was purchased and modified. The aircraft made use of a Pixhawk flight controller and a Odroid XU4 companion computer, which resulted in the computer injecting commands into the flight controller. Robot Operating System was installed and used on the companion computer to integrate the vision system and the aircraft. The vision system was designed to help develop a landing system where the aircraft would land on an ArUco marker. The vision system also allowed the aircraft to detect and follow humans. A Software in the Loop (SITL) was run alongside Gazebo, allowing the developed landing system and the human detecting system to be simulated and tested. The developed landing system was implemented on the aircraft, where the developed landing system was tested and compared to the aircraft’s current GPS based landing system. The developed landing system obtained a better overall accuracy , while also taking longer to land the aircraft compared to the GPS based landing system. There were also numerous manual and autonomous test flights implemented on the aircraft.
- Full Text:
Absent fathers: psychological and socio-economic implications for black children and directions for future research
- Magqamfana, Simnikiwe, Bazana, Sandiso
- Authors: Magqamfana, Simnikiwe , Bazana, Sandiso
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163443 , vital:41038 , DOI: 10.1080/14330237.2020.1744299
- Description: This study investigated fathers’ absence influences on the self-perceptions of South African young adults. Informants were five black university students (two females, three males; age range 20 to 28 years). They responded to semi-structured face-to-face interviews on self-perceptions from having matured in the absence of their biological fathers. Thematic analysis of the data revealed that the informants consider the father-absence when they grapple with material well-being shortage. Participants had mixed perceptions about the psychosocial effects on them from father-absence, with some believing to be thriving despite a history of father-absence. Overall, the findings suggest a need for caution in pathologising young adults with a history of father-absence as necessarily deprived.
- Full Text:
- Authors: Magqamfana, Simnikiwe , Bazana, Sandiso
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163443 , vital:41038 , DOI: 10.1080/14330237.2020.1744299
- Description: This study investigated fathers’ absence influences on the self-perceptions of South African young adults. Informants were five black university students (two females, three males; age range 20 to 28 years). They responded to semi-structured face-to-face interviews on self-perceptions from having matured in the absence of their biological fathers. Thematic analysis of the data revealed that the informants consider the father-absence when they grapple with material well-being shortage. Participants had mixed perceptions about the psychosocial effects on them from father-absence, with some believing to be thriving despite a history of father-absence. Overall, the findings suggest a need for caution in pathologising young adults with a history of father-absence as necessarily deprived.
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Academic readiness of students for higher education: a case for academic support at Rhodes University
- Authors: Khoza, Lebogang Peter
- Date: 2020
- Subjects: College student development programs -- South Africa -- Makhanda , Dropouts -- Prevention , College students -- South Africa-- Makhanda -- Social conditions , School failure -- South Africa -- Makhanda , Academic achievement-- South Africa -- Makhanda , Student adjustment -- South Africa -- Makhanda , Counseling in higher education -- South Africa -- Makhanda , Student Integration Model , Conceptual Framework Model , Geometric Design of Student Persistence
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/147848 , vital:38678
- Description: The worrying existence of incidences of student retention, poor pass rates and an increase in repetition rates is a cause for concern for institutions of higher learning in South Africa. The problem of student retention is not new in our institutions of higher learning. Support structures, strategies, and policies need to be developed for different academic and social challenges that students face daily. This study explores the need for academic support at Rhodes University; it also explores the internal and external problems that students face, the perceptions and experiences of students on academic support available to them. The study implemented a narrative research approach implanted within a qualitative research framework. Data was collected through a questionnaire, and narrative interviews. Tinto’s Student Integration Model was used to analyse the data in this study and was supplemented by Louw’s conceptual framework model and Swail’s Geometric Design of Student Persistence. These three models position the student experience as the foundation for academic support programmes and development. The study argues that as long as effective and adequate academic support is lacking, students will continue to experience difficulties in completing their studies. The findings from the study reveal that at present, Rhodes University provides support to students who are in extended studies. However, this support system disadvantages many students, notably those not in the extended studies programme. As a result, such students are not supported through strategies and structures that extended studies students receive. Furthermore, the data generates internal and external problems that student face daily, as a result, the findings showed that there is a need for academic support at Rhodes. The study recommends that Rhodes University must establish an academic unit that will provide academic support to all students registered in the university.
- Full Text:
- Authors: Khoza, Lebogang Peter
- Date: 2020
- Subjects: College student development programs -- South Africa -- Makhanda , Dropouts -- Prevention , College students -- South Africa-- Makhanda -- Social conditions , School failure -- South Africa -- Makhanda , Academic achievement-- South Africa -- Makhanda , Student adjustment -- South Africa -- Makhanda , Counseling in higher education -- South Africa -- Makhanda , Student Integration Model , Conceptual Framework Model , Geometric Design of Student Persistence
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/147848 , vital:38678
- Description: The worrying existence of incidences of student retention, poor pass rates and an increase in repetition rates is a cause for concern for institutions of higher learning in South Africa. The problem of student retention is not new in our institutions of higher learning. Support structures, strategies, and policies need to be developed for different academic and social challenges that students face daily. This study explores the need for academic support at Rhodes University; it also explores the internal and external problems that students face, the perceptions and experiences of students on academic support available to them. The study implemented a narrative research approach implanted within a qualitative research framework. Data was collected through a questionnaire, and narrative interviews. Tinto’s Student Integration Model was used to analyse the data in this study and was supplemented by Louw’s conceptual framework model and Swail’s Geometric Design of Student Persistence. These three models position the student experience as the foundation for academic support programmes and development. The study argues that as long as effective and adequate academic support is lacking, students will continue to experience difficulties in completing their studies. The findings from the study reveal that at present, Rhodes University provides support to students who are in extended studies. However, this support system disadvantages many students, notably those not in the extended studies programme. As a result, such students are not supported through strategies and structures that extended studies students receive. Furthermore, the data generates internal and external problems that student face daily, as a result, the findings showed that there is a need for academic support at Rhodes. The study recommends that Rhodes University must establish an academic unit that will provide academic support to all students registered in the university.
- Full Text:
Acceptance of ambulatory blood pressure monitoring in a semi-rural population in South Africa:
- Chiwanza, Farisai, Irwin, Yoland, Dowse, Ros
- Authors: Chiwanza, Farisai , Irwin, Yoland , Dowse, Ros
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157072 , vital:40084 , DOI: https://doi.org/10.4102/hsag.v25i0.1336
- Description: Ambulatory blood pressure monitoring is a valuable tool that helps in providing an insight into the diagnosis and management of hypertension; however, no evidence exists of its acceptance in the diverse South African population. We assessed the acceptance of an ambulatory blood pressure monitor in patients attending public sector primary health care (PHC) clinics. Five PHC clinics in the Makana subdistrict in the Eastern Cape.
- Full Text:
- Authors: Chiwanza, Farisai , Irwin, Yoland , Dowse, Ros
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/157072 , vital:40084 , DOI: https://doi.org/10.4102/hsag.v25i0.1336
- Description: Ambulatory blood pressure monitoring is a valuable tool that helps in providing an insight into the diagnosis and management of hypertension; however, no evidence exists of its acceptance in the diverse South African population. We assessed the acceptance of an ambulatory blood pressure monitor in patients attending public sector primary health care (PHC) clinics. Five PHC clinics in the Makana subdistrict in the Eastern Cape.
- Full Text:
Activity of diverse chalcones against several targets: statistical analysis of a high-throughput virtual screen of a custom chalcone library
- Authors: Sarron, Arthur F D
- Date: 2020
- Subjects: Acetophenone , Benzaldehyde , Ketones , Pyruvate kinase , Drug development , Aromatic compounds , Heat shock proteins
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/116028 , vital:34291
- Description: Chalcone family molecules are well known to have therapeutic proprieties (anti-inflammatory, anti-microbial or anti-cancer, etc). However the mechanism of action in some cases is not well known. A virtual library of this family of compounds was constructed using custom scripts, based on the aldol condensation, and this library was modified further to analogues by expansion of the α,β-unsaturated ketone linker. Acetophenone and benzaldehyde derivatives which are available and purchasable were used as a base to design the chalcone virtual library. 8063 chalcones were constructed and geometrically optimized with Gaussian 09. Their physicochemical characteristics linked to the Lipinski rules were analyzed with Knime and CDK. The entire library was after docked against several targets including HIV-1 integrase, MRSA pyruvate kinase, HSP90, COX-1, COX-2, ALR2, MAOA, MAOB, acetylcholinesterase, butyrylcholinesterase and PLA2. With the exception of MAOA, which does not have a crystal structure ligand, all dockings were validated by redocking the original ligand provided by the literature. These targets are known in the literature to be inhibited by chalcone-derivatives. However, specificity of the particular known chalcone inhibitors to the particular targets is not known. To this end the performance of the generated chalcone library against the list of targets was of interest. The binding energy of ligand-protein complexes was generally good across the library. Statistical analysis including principal component analysis and hierarchical clustering analysis were made in order to investigate for any physical/chemical characteristics which might explain what chalcone features affect the binding energy of the ligand-protein complexes. The spherical polar coordinates defining the orientation of the binding poses were also calculated and used in the statistical analysis. The statistical analysis has allowed us to hypothesize the importance of these radial distances and the polar angles of key atoms in the chalcones in binding to the pyruvate kinase crystal structure. This was validated by the docking of another small library of compound models in which the α,β-unsaturated ketone chain of the chalcone was replaced by incrementally longer conjugated chains. Further studies on the chalcones themselves reveal rotameric systems in both cis and trans-configurations (which may impact binding), and also studied was the effect of Topliss-based modification and its impact of binding to HSP90. Molecular dynamics confirmed good binding of identified chalcone hits.
- Full Text:
- Authors: Sarron, Arthur F D
- Date: 2020
- Subjects: Acetophenone , Benzaldehyde , Ketones , Pyruvate kinase , Drug development , Aromatic compounds , Heat shock proteins
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/116028 , vital:34291
- Description: Chalcone family molecules are well known to have therapeutic proprieties (anti-inflammatory, anti-microbial or anti-cancer, etc). However the mechanism of action in some cases is not well known. A virtual library of this family of compounds was constructed using custom scripts, based on the aldol condensation, and this library was modified further to analogues by expansion of the α,β-unsaturated ketone linker. Acetophenone and benzaldehyde derivatives which are available and purchasable were used as a base to design the chalcone virtual library. 8063 chalcones were constructed and geometrically optimized with Gaussian 09. Their physicochemical characteristics linked to the Lipinski rules were analyzed with Knime and CDK. The entire library was after docked against several targets including HIV-1 integrase, MRSA pyruvate kinase, HSP90, COX-1, COX-2, ALR2, MAOA, MAOB, acetylcholinesterase, butyrylcholinesterase and PLA2. With the exception of MAOA, which does not have a crystal structure ligand, all dockings were validated by redocking the original ligand provided by the literature. These targets are known in the literature to be inhibited by chalcone-derivatives. However, specificity of the particular known chalcone inhibitors to the particular targets is not known. To this end the performance of the generated chalcone library against the list of targets was of interest. The binding energy of ligand-protein complexes was generally good across the library. Statistical analysis including principal component analysis and hierarchical clustering analysis were made in order to investigate for any physical/chemical characteristics which might explain what chalcone features affect the binding energy of the ligand-protein complexes. The spherical polar coordinates defining the orientation of the binding poses were also calculated and used in the statistical analysis. The statistical analysis has allowed us to hypothesize the importance of these radial distances and the polar angles of key atoms in the chalcones in binding to the pyruvate kinase crystal structure. This was validated by the docking of another small library of compound models in which the α,β-unsaturated ketone chain of the chalcone was replaced by incrementally longer conjugated chains. Further studies on the chalcones themselves reveal rotameric systems in both cis and trans-configurations (which may impact binding), and also studied was the effect of Topliss-based modification and its impact of binding to HSP90. Molecular dynamics confirmed good binding of identified chalcone hits.
- Full Text:
Addo Elephant National Park 1900 – 1955: An Environmental History of the struggle between elephants and emerging commercial farmers in the Sundays River Valley
- Jones,Nicholas Austen Inskip
- Authors: Jones,Nicholas Austen Inskip
- Date: 2020
- Subjects: Wildlife conservation -- South Africa -- Addo National Park
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46922 , vital:39733
- Description: The research covers the first half of the 20th Century in the Sundays River Valley, and the relations between the elephants and the local farmers. The research includes some discussion of the implementation of new ideas to agriculture, irrigation, and colonial settlement with the interplay between the colonial farmers and the Administration. There is reference to the early politics surrounding nature conservation and the difficulties faced by farmers from wildlife and the difficulty wildlife face trying to co-exist alongside early intensive commercial agriculture.Included is the decision making process of the Colonial administration with reference to wildlife and agriculture relating to charismatic animal species.
- Full Text:
- Authors: Jones,Nicholas Austen Inskip
- Date: 2020
- Subjects: Wildlife conservation -- South Africa -- Addo National Park
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46922 , vital:39733
- Description: The research covers the first half of the 20th Century in the Sundays River Valley, and the relations between the elephants and the local farmers. The research includes some discussion of the implementation of new ideas to agriculture, irrigation, and colonial settlement with the interplay between the colonial farmers and the Administration. There is reference to the early politics surrounding nature conservation and the difficulties faced by farmers from wildlife and the difficulty wildlife face trying to co-exist alongside early intensive commercial agriculture.Included is the decision making process of the Colonial administration with reference to wildlife and agriculture relating to charismatic animal species.
- Full Text:
Addressing flux suppression, radio frequency interference, and selection of optimal solution intervals during radio interferometric calibration
- Authors: Sob, Ulrich Armel Mbou
- Date: 2020
- Subjects: CubiCal (Software) , Radio -- Interference , Imaging systems in astronomy , Algorithms , Astronomical instruments -- Calibration , Astronomy -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/147714 , vital:38663
- Description: The forthcoming Square Kilometre Array is expected to provide answers to some of the most intriguing questions about our Universe. However, as it is already noticeable from MeerKAT and other precursors, the amounts of data produced by these new instruments are significantly challenging to calibrate and image. Calibration of radio interferometric data is usually biased by incomplete sky models and radio frequency interference (RFI) resulting in calibration artefacts that limit the dynamic range and image fidelity of the resulting images. One of the most noticeable of these artefacts is the formation of spurious sources which causes suppression of real emissions. Fortunately, it has been shown that calibration algorithms employing heavy-tailed likelihood functions are less susceptible to this due to their robustness against outliers. Leveraging on recent developments in the field of complex optimisation, we implement a robust calibration algorithm using a Student’s t likelihood function and Wirtinger derivatives. The new algorithm, dubbed the robust solver, is incorporated as a subroutine into the newly released calibration software package CubiCal. We perform statistical analysis on the distribution of visibilities and provide an insight into the functioning of the robust solver and describe different scenarios where it will improve calibration. We use simulations to show that the robust solver effectively reduces the amount of flux suppressed from unmodelled sources both in direction independent and direction dependent calibration. Furthermore, the robust solver is shown to successfully mitigate the effects of low-level RFI when applied to a simulated and a real VLA dataset. Finally, we demonstrate that there are close links between the amount of flux suppressed from sources, the effects of the RFI and the employed solution interval during radio interferometric calibration. Hence, we investigate the effects of solution intervals and the different factors to consider in order to select adequate solution intervals. Furthermore, we propose a practical brute force method for selecting optimal solution intervals. The proposed method is successfully applied to a VLA dataset.
- Full Text:
- Authors: Sob, Ulrich Armel Mbou
- Date: 2020
- Subjects: CubiCal (Software) , Radio -- Interference , Imaging systems in astronomy , Algorithms , Astronomical instruments -- Calibration , Astronomy -- Data processing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/147714 , vital:38663
- Description: The forthcoming Square Kilometre Array is expected to provide answers to some of the most intriguing questions about our Universe. However, as it is already noticeable from MeerKAT and other precursors, the amounts of data produced by these new instruments are significantly challenging to calibrate and image. Calibration of radio interferometric data is usually biased by incomplete sky models and radio frequency interference (RFI) resulting in calibration artefacts that limit the dynamic range and image fidelity of the resulting images. One of the most noticeable of these artefacts is the formation of spurious sources which causes suppression of real emissions. Fortunately, it has been shown that calibration algorithms employing heavy-tailed likelihood functions are less susceptible to this due to their robustness against outliers. Leveraging on recent developments in the field of complex optimisation, we implement a robust calibration algorithm using a Student’s t likelihood function and Wirtinger derivatives. The new algorithm, dubbed the robust solver, is incorporated as a subroutine into the newly released calibration software package CubiCal. We perform statistical analysis on the distribution of visibilities and provide an insight into the functioning of the robust solver and describe different scenarios where it will improve calibration. We use simulations to show that the robust solver effectively reduces the amount of flux suppressed from unmodelled sources both in direction independent and direction dependent calibration. Furthermore, the robust solver is shown to successfully mitigate the effects of low-level RFI when applied to a simulated and a real VLA dataset. Finally, we demonstrate that there are close links between the amount of flux suppressed from sources, the effects of the RFI and the employed solution interval during radio interferometric calibration. Hence, we investigate the effects of solution intervals and the different factors to consider in order to select adequate solution intervals. Furthermore, we propose a practical brute force method for selecting optimal solution intervals. The proposed method is successfully applied to a VLA dataset.
- Full Text:
Adol-Safety: A Framework for Empowering Parents to be Aware of Social Network Threats Affecting Adolescents
- Mjoli, Phumelela, Shibeshi, Z
- Authors: Mjoli, Phumelela , Shibeshi, Z
- Date: 2020
- Subjects: Social networks , Social media|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12016 , vital:39127
- Description: The use of social networks has grown so much that adolescents have become active members of various social networks such as Twitter, Facebook, and Instagram, etc. The gradual change in how people choose to communicate, socialize and share ideas today has influenced adolescents to an extent that they find themselves wanting to engage more on social networks than they really should due to peer pressure. Whenever a person joins social networks or browses the Internet, they by default are exposed and become vulnerable to many cyber threats. Cyber threats are driven by users that have negative intentions on the Internet or social networks. Adolescents are no exception to these cyber threats. The findings of this research reveal that threats such as cyberbullying, harassment, and online predators to name a few are often designed to abuse and affect adolescents). Therefore, this research aims to prevent such threats from prevailing by empowering parents to be aware of the threats that affect their adolescents in an online environment, which typically includes social networks. To achieve this, this research starts by investigating the cyber threats that affect adolescents and then explores ways that can be used to empower parents. A framework is developed to handle this. The framework includes strategies that parents can adopt and ways in which safety on social networks can be increased, as well as guidelines that can be followed in order to prevent cyber threats. The framework also aims to enhance a parent-child relationship that can help in preventing social network threats. Lastly, the framework is implemented as a knowledgesharing website that can be used by parents to receive and give an insight into social network threats that influence adolescents on social networks.
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- Authors: Mjoli, Phumelela , Shibeshi, Z
- Date: 2020
- Subjects: Social networks , Social media|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12016 , vital:39127
- Description: The use of social networks has grown so much that adolescents have become active members of various social networks such as Twitter, Facebook, and Instagram, etc. The gradual change in how people choose to communicate, socialize and share ideas today has influenced adolescents to an extent that they find themselves wanting to engage more on social networks than they really should due to peer pressure. Whenever a person joins social networks or browses the Internet, they by default are exposed and become vulnerable to many cyber threats. Cyber threats are driven by users that have negative intentions on the Internet or social networks. Adolescents are no exception to these cyber threats. The findings of this research reveal that threats such as cyberbullying, harassment, and online predators to name a few are often designed to abuse and affect adolescents). Therefore, this research aims to prevent such threats from prevailing by empowering parents to be aware of the threats that affect their adolescents in an online environment, which typically includes social networks. To achieve this, this research starts by investigating the cyber threats that affect adolescents and then explores ways that can be used to empower parents. A framework is developed to handle this. The framework includes strategies that parents can adopt and ways in which safety on social networks can be increased, as well as guidelines that can be followed in order to prevent cyber threats. The framework also aims to enhance a parent-child relationship that can help in preventing social network threats. Lastly, the framework is implemented as a knowledgesharing website that can be used by parents to receive and give an insight into social network threats that influence adolescents on social networks.
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African Foreign Policies: Selecting signifiers to explain agency
- Authors: Bischoff, Paul-Henri
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/161716 , vital:40657 , ISBN 9780367348281 , https://www.routledge.com/African-Foreign-Policies-Selecting-Signifiers-to-Explain-Agency/Bischoff/p/book/9780367348281
- Description: This book explores, at a time when several powers have become serious players on the continent, aspects of African agency, past and present, by African writers on foreign policy, representative of geography, language and state size.
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- Authors: Bischoff, Paul-Henri
- Date: 2020
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/161716 , vital:40657 , ISBN 9780367348281 , https://www.routledge.com/African-Foreign-Policies-Selecting-Signifiers-to-Explain-Agency/Bischoff/p/book/9780367348281
- Description: This book explores, at a time when several powers have become serious players on the continent, aspects of African agency, past and present, by African writers on foreign policy, representative of geography, language and state size.
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Afromelampsalta, a new genus, a new species, and five new combinations of African cicadettine cicadas (Hemiptera: Cicadidae: Cicadettinae):
- Sanborn, Allen F, Villet, M H (Martin Herrer)
- Authors: Sanborn, Allen F , Villet, M H (Martin Herrer)
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140680 , vital:37909
- Description: Afromelampsalta n. gen. is described for African species currently assigned to the genera Melampsalta Kolenati, 1857. Cicadetta Kolenati, 1857 and Pauropsalta Goding and Froggatt, 1904, and the new species Afromelampsalta luteofasciata n. gen., n. sp. is described. Afromelampsalta aethiopica (Distant, 1905) n. comb., A. cadisia (Walker, 1850) n. comb. and A. leucoptera (Germar, 1830) n. comb. are reassigned from Melampsalta to Afromelampsalta n. gen., A. limitata (Walker, 1852) n. comb. is transferred from Cicadetta Kolenati, 1857 and A. mimica (Distant ,1907) n. comb. is transferred from Pauropsalta Goding and Froggatt, 1904 to Afromelampsalta n. gen. Notes on the biology of the new species, a description of the exuvia of A. mimica n. comb., and a key to the species of African Cicadettini are provided.
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- Authors: Sanborn, Allen F , Villet, M H (Martin Herrer)
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140680 , vital:37909
- Description: Afromelampsalta n. gen. is described for African species currently assigned to the genera Melampsalta Kolenati, 1857. Cicadetta Kolenati, 1857 and Pauropsalta Goding and Froggatt, 1904, and the new species Afromelampsalta luteofasciata n. gen., n. sp. is described. Afromelampsalta aethiopica (Distant, 1905) n. comb., A. cadisia (Walker, 1850) n. comb. and A. leucoptera (Germar, 1830) n. comb. are reassigned from Melampsalta to Afromelampsalta n. gen., A. limitata (Walker, 1852) n. comb. is transferred from Cicadetta Kolenati, 1857 and A. mimica (Distant ,1907) n. comb. is transferred from Pauropsalta Goding and Froggatt, 1904 to Afromelampsalta n. gen. Notes on the biology of the new species, a description of the exuvia of A. mimica n. comb., and a key to the species of African Cicadettini are provided.
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Age is nothing but a number: Ben 10s, sugar mummies, and the South African gender order in the Daily Sun’s Facebook page
- Authors: Mlangeni, Ntombikayise Lina
- Date: 2020
- Subjects: May-December romances -- South Africa , Women in mass media , Men in mass media , Sex role in mass media , Masculinity in mass media , Feminism and mass media , Critical discourse analysis , Unemployment -- Social aspects -- South Africa , Daily Sun (South Africa) , Ben 10
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/167077 , vital:41435
- Description: This thesis examines how meanings of masculinity and femininity are negotiated by South Africans on a social media platform linked to a popular local tabloid newspaper. In particular it explores conversations surrounding the Ben 10 phenomenon on the Daily Sun’s Facebook page. A Ben 10 is commonly understood as a young man who enters into a sexual relationship with an older woman, mostly in township settings, and readers engage vociferously over the meanings of such relationships. Using a constructivist understanding of gender, a thematic analysis is used to examine the Facebook comments on the Daily Sun’s most popular Ben 10 stories. South Africa’s constitution promotes the right to gender equality and freedom, which contributes to the normalisation of sex in public conversations and political debate. However, with high levels of unemployment and poverty in South Africa, the narrative of masculine success through work remains relatively unattainable. This tension between the narrative of male-bread winner through work and the reality of South Africa’s poverty and unemployment has been referred to as the crisis of masculinity. This thesis will argue that tabloids can play a strong political role by providing an alternative public sphere and that they can also assist their readers in coping with life in a democratic society by creating an imagined community of people sharing common experiences.
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- Authors: Mlangeni, Ntombikayise Lina
- Date: 2020
- Subjects: May-December romances -- South Africa , Women in mass media , Men in mass media , Sex role in mass media , Masculinity in mass media , Feminism and mass media , Critical discourse analysis , Unemployment -- Social aspects -- South Africa , Daily Sun (South Africa) , Ben 10
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/167077 , vital:41435
- Description: This thesis examines how meanings of masculinity and femininity are negotiated by South Africans on a social media platform linked to a popular local tabloid newspaper. In particular it explores conversations surrounding the Ben 10 phenomenon on the Daily Sun’s Facebook page. A Ben 10 is commonly understood as a young man who enters into a sexual relationship with an older woman, mostly in township settings, and readers engage vociferously over the meanings of such relationships. Using a constructivist understanding of gender, a thematic analysis is used to examine the Facebook comments on the Daily Sun’s most popular Ben 10 stories. South Africa’s constitution promotes the right to gender equality and freedom, which contributes to the normalisation of sex in public conversations and political debate. However, with high levels of unemployment and poverty in South Africa, the narrative of masculine success through work remains relatively unattainable. This tension between the narrative of male-bread winner through work and the reality of South Africa’s poverty and unemployment has been referred to as the crisis of masculinity. This thesis will argue that tabloids can play a strong political role by providing an alternative public sphere and that they can also assist their readers in coping with life in a democratic society by creating an imagined community of people sharing common experiences.
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Age of squid Loligo reynaudii d’Orbigny, 1845, and its possible use to test effectiveness of the closed season in protecting this resource
- Mwanangombe, Collette Habani
- Authors: Mwanangombe, Collette Habani
- Date: 2020
- Subjects: Loliginidae -- Spawning -- South Africa , Loliginidae -- Age determination , Loligo fisheries -- South Africa , Fishery management -- South Africa , Otoliths , Loliginidae – Eggs -- Incubation , Loliginidae – Growth , Fish stock assessment -- South Africa , Recruitment (Population biology) -- South Africa , Loligo reynaudii d’Orbigny
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144333 , vital:38336
- Description: This study presents age distributions representing populations of adult Loligo reynaudii, together with the results of spawning and commercial catches to assist in understanding the beneficial role of the closed season. The results were based on 791 samples collected during three closed seasons (November: 2003, 2004 and 2005) and out of closed season during April/May 2005. Age and predicted growth were examined by counting daily rings on statolith microstructures. The age in days after hatching ranged from 168 to 484 days (71-425 mm) in males and from 125 to 478 days (83-263 mm) in females. Average age at spawning was found to be 323 days in males and 316 days in females. Population estimates of growth rates were best described by a linear growth model which revealed that males grew faster than females in length as they grew older with growth rate ranging between 0.63 to 0.83 mm per day for males and between 0.22 to 0.32 mm per day for females. Back-calculated hatch dates and later egg-laying events for parental populations were determined. Results from back calculated egg laying dates (presented as percentage of frequency of all laying dates) indicated a highest total of 36%, 39% and 15% of eggs from all samples were laid during the closed season and nine days after the closed season during year 2003, 2004 and 2005 respectively. Monthly commercial total catches (2002-2005) showed an increase from November soon after the fishery resumed, up until the month of January. Daily catches were highest in November (up to 290 tonnes) relative to the daily catches observed in December and January in all the years. Results led to the conclusion that the closed season (25 October to 22 November) is beneficial for both the chokka resource and the fishery. This is because: a) there is time for enough spawning biomass to accumulate, which subsequently results in high catches (good fishery), in the current year, best immediately after season opens in November; b) there is a link in the results between egg laying dates in the period of closed season and immediately afterwards, and the magnitude of catches in last nine days of November.
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- Authors: Mwanangombe, Collette Habani
- Date: 2020
- Subjects: Loliginidae -- Spawning -- South Africa , Loliginidae -- Age determination , Loligo fisheries -- South Africa , Fishery management -- South Africa , Otoliths , Loliginidae – Eggs -- Incubation , Loliginidae – Growth , Fish stock assessment -- South Africa , Recruitment (Population biology) -- South Africa , Loligo reynaudii d’Orbigny
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144333 , vital:38336
- Description: This study presents age distributions representing populations of adult Loligo reynaudii, together with the results of spawning and commercial catches to assist in understanding the beneficial role of the closed season. The results were based on 791 samples collected during three closed seasons (November: 2003, 2004 and 2005) and out of closed season during April/May 2005. Age and predicted growth were examined by counting daily rings on statolith microstructures. The age in days after hatching ranged from 168 to 484 days (71-425 mm) in males and from 125 to 478 days (83-263 mm) in females. Average age at spawning was found to be 323 days in males and 316 days in females. Population estimates of growth rates were best described by a linear growth model which revealed that males grew faster than females in length as they grew older with growth rate ranging between 0.63 to 0.83 mm per day for males and between 0.22 to 0.32 mm per day for females. Back-calculated hatch dates and later egg-laying events for parental populations were determined. Results from back calculated egg laying dates (presented as percentage of frequency of all laying dates) indicated a highest total of 36%, 39% and 15% of eggs from all samples were laid during the closed season and nine days after the closed season during year 2003, 2004 and 2005 respectively. Monthly commercial total catches (2002-2005) showed an increase from November soon after the fishery resumed, up until the month of January. Daily catches were highest in November (up to 290 tonnes) relative to the daily catches observed in December and January in all the years. Results led to the conclusion that the closed season (25 October to 22 November) is beneficial for both the chokka resource and the fishery. This is because: a) there is time for enough spawning biomass to accumulate, which subsequently results in high catches (good fishery), in the current year, best immediately after season opens in November; b) there is a link in the results between egg laying dates in the period of closed season and immediately afterwards, and the magnitude of catches in last nine days of November.
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Agents sans frontiers: cross-border aquatic weed biological control in the rivers of southern Mozambique
- Langa, Silvia D F, Hill, Martin P, Compton, Stephen G
- Authors: Langa, Silvia D F , Hill, Martin P , Compton, Stephen G
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148998 , vital:38794 , DOI: 10.2989/16085914.2020.1749551
- Description: Biological control is an effective ways of controlling aquatic plants, especially in South Africa. Release of biological control agents has been limited to Mozambique, where water hyacinth (Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae)), water lettuce (Pistia stratiotes L. (Araceae)), red water ferns (Azolla spp. (Azollaceae)) and salvinia (Salvinia molesta DS Mitch. (Salviniaceae)) are significant weeds in the south of the country. In 2009, we assessed the status of these weeds in seven rivers across southern Mozambique and recorded whether any biocontrol agents were present.
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- Authors: Langa, Silvia D F , Hill, Martin P , Compton, Stephen G
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148998 , vital:38794 , DOI: 10.2989/16085914.2020.1749551
- Description: Biological control is an effective ways of controlling aquatic plants, especially in South Africa. Release of biological control agents has been limited to Mozambique, where water hyacinth (Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae)), water lettuce (Pistia stratiotes L. (Araceae)), red water ferns (Azolla spp. (Azollaceae)) and salvinia (Salvinia molesta DS Mitch. (Salviniaceae)) are significant weeds in the south of the country. In 2009, we assessed the status of these weeds in seven rivers across southern Mozambique and recorded whether any biocontrol agents were present.
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