A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
Possible futures for the health system of South Africa towards 2030
- Authors: Lourens, Stephanus Johannes
- Date: 2020
- Subjects: Health services administration -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/48720 , vital:41065
- Description: The South African health system is in crisis. To improve access to health services and move towards universal health coverage the South African government has decided to implement National Health Insurance (NHI). The implementation of such health reforms to the health system of SA is further complicated by the rapidly changing technological environment in the form of the fourth industrial revolution. The NHI and the fourth industrial revolution are expected to impact on the health system of the country, but what the impacts will be remain unclear. A review of the theory and practice of future studies support the notion that change management for healthcare organisations operating within the SA health system must be approached differently. The volatility introduced by the NHI within the context of the fourth industrial revolution necessitates the creation of strategic foresight using futures methodologies. The research has attempted to gain an understanding of the impact of National Health Insurance and the fourth industrial revolution on the health system of SA through the creation of possible futures for the health system, in the form of four alternative scenarios, towards 2030. The six pillars of future studies as stated by Inayatullah (2008) were used as a research methodology and assisted in the mapping, anticipation and timing of the issues facing the health system. The future was deepened using causal layered analysis and alternative futures were constructed through double-variable scenario creation methods using the worldviews identified during the causal layered analysis. From the constructed scenarios the research attempted to identify the preferred future for the health system of South Africa. The preferred future was used in the development of the Future Vision for the Health System of South Africa towards 2030. It is clear to achieve the desired health system towards 2030 the private and the public sectors must collaborate to create a hybrid health system which is supported by fourth industrial revolution technologies.
- Full Text:
- Date Issued: 2020
- Authors: Lourens, Stephanus Johannes
- Date: 2020
- Subjects: Health services administration -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/48720 , vital:41065
- Description: The South African health system is in crisis. To improve access to health services and move towards universal health coverage the South African government has decided to implement National Health Insurance (NHI). The implementation of such health reforms to the health system of SA is further complicated by the rapidly changing technological environment in the form of the fourth industrial revolution. The NHI and the fourth industrial revolution are expected to impact on the health system of the country, but what the impacts will be remain unclear. A review of the theory and practice of future studies support the notion that change management for healthcare organisations operating within the SA health system must be approached differently. The volatility introduced by the NHI within the context of the fourth industrial revolution necessitates the creation of strategic foresight using futures methodologies. The research has attempted to gain an understanding of the impact of National Health Insurance and the fourth industrial revolution on the health system of SA through the creation of possible futures for the health system, in the form of four alternative scenarios, towards 2030. The six pillars of future studies as stated by Inayatullah (2008) were used as a research methodology and assisted in the mapping, anticipation and timing of the issues facing the health system. The future was deepened using causal layered analysis and alternative futures were constructed through double-variable scenario creation methods using the worldviews identified during the causal layered analysis. From the constructed scenarios the research attempted to identify the preferred future for the health system of South Africa. The preferred future was used in the development of the Future Vision for the Health System of South Africa towards 2030. It is clear to achieve the desired health system towards 2030 the private and the public sectors must collaborate to create a hybrid health system which is supported by fourth industrial revolution technologies.
- Full Text:
- Date Issued: 2020
Performance, functionalism and form in Ịzọn oral poety
- Authors: Armstrong, Imomotimi
- Date: 2020
- Subjects: Ijo (African people , Ijo language , Folk poetry, Ijo , Folk poetry -- Nigeria
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140641 , vital:37906
- Description: Since the publication of Ruth Finnegan’s influential Oral Literature in Africa, way back in 1970, scholars have been paying earnest attention to oral traditions on the African continent. That seminal book pointed out to Africanist scholars the need to urgently collect and document the oral literatures of their various ethnic groups before they die out. However, it is the verbal arts of the major ethnic groups on the continent that very often benefit from this collection and documentation, as it were. Therefore, this study sought to examine the oral poetry of the Ịzọn, a minority ethnic nationality, located in the oil-rich Niger Delta region of Nigeria. The study employed unstructured interviews and participant observations to collect the data for the research. The transcribed and translated data was examined through three eclectic theories to the study of folklore: Russian formalism, performance and functionalism. The study found out that Ịzọn oral poetry is a combination of songs and one person’s praise chants. Moreover, it revealed that praise chanting is a recent practice amongst the Ịzọn that was introduced into Ịzọnland by Chief Adolphus Munamuna from the Yoruba of southwestern Nigeria. Furthermore, the study established that oral poetry plays important roles amongst the people. Besides, it ascertained that the performance of some sub-categories of the poetry is highly dramatic and theatrical. It also discovered that stylistic techniques such as formula, parallelism, proverb, ideophone, praise title, metaphor, repetition, alliteration, assonance, vowel lengthening, amongst others, give the poetry the quality of “literariness.” In addition, the study found out that the poetry, like oral poetry in other ethnic groups, demonstrates the three qualities of change, adaptability and survival. The study has contributed to existing scholarship on African oral traditions in the sense of collecting, documenting and generating awareness on Ịzọn oral poetry, most importantly pointing out the existence of praise chanting amongst a people who had no such culture and the conditions that gave rise to that practice.
- Full Text:
- Date Issued: 2020
- Authors: Armstrong, Imomotimi
- Date: 2020
- Subjects: Ijo (African people , Ijo language , Folk poetry, Ijo , Folk poetry -- Nigeria
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/140641 , vital:37906
- Description: Since the publication of Ruth Finnegan’s influential Oral Literature in Africa, way back in 1970, scholars have been paying earnest attention to oral traditions on the African continent. That seminal book pointed out to Africanist scholars the need to urgently collect and document the oral literatures of their various ethnic groups before they die out. However, it is the verbal arts of the major ethnic groups on the continent that very often benefit from this collection and documentation, as it were. Therefore, this study sought to examine the oral poetry of the Ịzọn, a minority ethnic nationality, located in the oil-rich Niger Delta region of Nigeria. The study employed unstructured interviews and participant observations to collect the data for the research. The transcribed and translated data was examined through three eclectic theories to the study of folklore: Russian formalism, performance and functionalism. The study found out that Ịzọn oral poetry is a combination of songs and one person’s praise chants. Moreover, it revealed that praise chanting is a recent practice amongst the Ịzọn that was introduced into Ịzọnland by Chief Adolphus Munamuna from the Yoruba of southwestern Nigeria. Furthermore, the study established that oral poetry plays important roles amongst the people. Besides, it ascertained that the performance of some sub-categories of the poetry is highly dramatic and theatrical. It also discovered that stylistic techniques such as formula, parallelism, proverb, ideophone, praise title, metaphor, repetition, alliteration, assonance, vowel lengthening, amongst others, give the poetry the quality of “literariness.” In addition, the study found out that the poetry, like oral poetry in other ethnic groups, demonstrates the three qualities of change, adaptability and survival. The study has contributed to existing scholarship on African oral traditions in the sense of collecting, documenting and generating awareness on Ịzọn oral poetry, most importantly pointing out the existence of praise chanting amongst a people who had no such culture and the conditions that gave rise to that practice.
- Full Text:
- Date Issued: 2020
Southern African HIV Clinicians Society guidelines for antiretroviral therapy in adults: 2020 update
- Authors: David Stead
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3281 , vital:43293 , https://doi.org/10.4102/sajhivmed.v21i1.1115
- Description: What is new in the 2020 guidelines update? Key updates ÿ A recommendation for dolutegravir (DTG)-based therapies as the preferred first-line antiretroviral therapy (ART) option (section 11). ÿ Updated guidelines for second- and third-line ART regimens (section 13). ÿ New recommendations on the management of patients on DTG-based therapies who have an elevated viral load (section 12). ÿ A lowering of the threshold for virological failure from 1000 copies/mL to 50 copies/mL (section 8). ÿ A recommendation against routine cluster of differentiation 4 (CD4+) monitoring in patients who are clinically well once the CD4+ count is > 200 cells/μL (section 9). ÿ Updated recommendations for isoniazid preventive therapy (IPT) in human immunodeficiency virus (HIV)-positive patients (section 27). ÿ A recommendation for the use of low-dose prednisone as prophylaxis for paradoxical tuberculosis (TB) immune reconstitution inflammatory syndrome (IRIS) in TB/HIV co-infected patients commencing ART within 1 month of TB therapy (section 26).
- Full Text:
- Date Issued: 2020
Southern African HIV Clinicians Society guidelines for antiretroviral therapy in adults: 2020 update
- Authors: David Stead
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3281 , vital:43293 , https://doi.org/10.4102/sajhivmed.v21i1.1115
- Description: What is new in the 2020 guidelines update? Key updates ÿ A recommendation for dolutegravir (DTG)-based therapies as the preferred first-line antiretroviral therapy (ART) option (section 11). ÿ Updated guidelines for second- and third-line ART regimens (section 13). ÿ New recommendations on the management of patients on DTG-based therapies who have an elevated viral load (section 12). ÿ A lowering of the threshold for virological failure from 1000 copies/mL to 50 copies/mL (section 8). ÿ A recommendation against routine cluster of differentiation 4 (CD4+) monitoring in patients who are clinically well once the CD4+ count is > 200 cells/μL (section 9). ÿ Updated recommendations for isoniazid preventive therapy (IPT) in human immunodeficiency virus (HIV)-positive patients (section 27). ÿ A recommendation for the use of low-dose prednisone as prophylaxis for paradoxical tuberculosis (TB) immune reconstitution inflammatory syndrome (IRIS) in TB/HIV co-infected patients commencing ART within 1 month of TB therapy (section 26).
- Full Text:
- Date Issued: 2020
Contesting boundaries: a case of municipal demarcation disputes in Vuwani Vhembe District
- Authors: Khowa, Thandeka Promise
- Date: 2020
- Subjects: Geographical boundaries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50767 , vital:42670
- Description: The research study in Vuwani Vhembe district sought to investigate demarcation disputes, the relationship between service delivery and demarcation disputes. The study further investigates the role of municipal demarcation board and local government adherence to sound governance principles and the causes of the demarcation dispute in Vuwani. The study additionally examines the conceptions and misconceptions, their impact on the current demarcation disputes in Vuwani. It further intended to establish the role and involvement of Vuwani stakeholders such as traditional structures/ leaders, civil unions, community members etc. in the processes of demarcating Vuwani. “What is the cause of Vuwani community member’s rejection of the re-demarcation, which is said to correct the past spatial injustices and promote municipal sizing, thus enabling better performance in service provision by municipalities?” The study employed a mixed-method involving the use of both quantitative (mini-survey) and qualitative (use of in-depth, semi structures interviews and focus group discussions). Research findings suggest that re-demarcation is a sensitive aspect/process in South Africa, mainly due to the past Apartheid era. There was forceful removal of people from their land supported by Apartheid legislation such as the Native Land Act 1913, Group Act 1950, Native Resettlement Act 1954 etc. Thus, fears of the past Apartheid system cloud any attempt to correct spatial injustices of the country. The new democratic South African government, therefore, needs to be cautious in its acts to correct the spatial injustices, thus adhering to sound governance principles. Findings reveal that several misconceptions and lack of adherence of good governance principles by the Municipal Demarcation Board and Local government have, to some extent, fueled the demarcation disputes in Vuwani. Municipal performance in the rendering of service delivery has a major impact and contributes to the community’s acceptance or rejection of demarcation/ amalgamations. The study further reveals that in Vuwani municipal performance with the establishment of the new Collins Chabane municipality has been clouded by fear of the unknown as this form of “demarcation of establishing a new municipality” altogether is relatively new. Rural land authority, the role of traditional leaders, ethnicity ties have all been found to have contributed to the disputes in Vuwani. Limpopo Province is home to three ethnic groups, namely, vaVhenda, baPedi and xiTsonga. The study findings have presented traits of tribalism as contributing to on-going demarcation disputes in Vuwani.
- Full Text:
- Date Issued: 2020
- Authors: Khowa, Thandeka Promise
- Date: 2020
- Subjects: Geographical boundaries
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/50767 , vital:42670
- Description: The research study in Vuwani Vhembe district sought to investigate demarcation disputes, the relationship between service delivery and demarcation disputes. The study further investigates the role of municipal demarcation board and local government adherence to sound governance principles and the causes of the demarcation dispute in Vuwani. The study additionally examines the conceptions and misconceptions, their impact on the current demarcation disputes in Vuwani. It further intended to establish the role and involvement of Vuwani stakeholders such as traditional structures/ leaders, civil unions, community members etc. in the processes of demarcating Vuwani. “What is the cause of Vuwani community member’s rejection of the re-demarcation, which is said to correct the past spatial injustices and promote municipal sizing, thus enabling better performance in service provision by municipalities?” The study employed a mixed-method involving the use of both quantitative (mini-survey) and qualitative (use of in-depth, semi structures interviews and focus group discussions). Research findings suggest that re-demarcation is a sensitive aspect/process in South Africa, mainly due to the past Apartheid era. There was forceful removal of people from their land supported by Apartheid legislation such as the Native Land Act 1913, Group Act 1950, Native Resettlement Act 1954 etc. Thus, fears of the past Apartheid system cloud any attempt to correct spatial injustices of the country. The new democratic South African government, therefore, needs to be cautious in its acts to correct the spatial injustices, thus adhering to sound governance principles. Findings reveal that several misconceptions and lack of adherence of good governance principles by the Municipal Demarcation Board and Local government have, to some extent, fueled the demarcation disputes in Vuwani. Municipal performance in the rendering of service delivery has a major impact and contributes to the community’s acceptance or rejection of demarcation/ amalgamations. The study further reveals that in Vuwani municipal performance with the establishment of the new Collins Chabane municipality has been clouded by fear of the unknown as this form of “demarcation of establishing a new municipality” altogether is relatively new. Rural land authority, the role of traditional leaders, ethnicity ties have all been found to have contributed to the disputes in Vuwani. Limpopo Province is home to three ethnic groups, namely, vaVhenda, baPedi and xiTsonga. The study findings have presented traits of tribalism as contributing to on-going demarcation disputes in Vuwani.
- Full Text:
- Date Issued: 2020
Practices, dynamics and discourses of cross-racial adoption: the case of Buffalo city municipality in South Africa
- Authors: Nyasha, Kausi
- Date: 2020
- Subjects: Interracial adoption -- South Africa -- Eastern Cape Adoption -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/18009 , vital:42003
- Description: This study investigated the practices, dynamics, and discourses pertaining to crossracial adoption (CRA) in the Buffalo City Municipality (BCM) in South Africa. The researcher made use of qualitative methods to collect and analyse relevant data, which was made from both the in-depth interviews and focus group discussions. The research sample comprised of six adoption social workers, ten adoptive parents and ten adoptees, who were selected by means of purposive non-random sampling. The researcher also made use of observations, in order to that relevant, valuable, and rich information could be obtained. All the data was subsequently analysed by means of thematic analysis. The principal findings of the study revealed that although it has been legal since 1991, the practices of CRA in South Africa continues to be controversial and that, in the vast majority of cases, it entails black children being adopted by white parents. Relevant discourses covered cultural genocide, the best interests of adopted children, racial identity, colour-blindness, acculturation, and racial consciousness. The phenomenon of CRA needed to be evaluated from all of these standpoints, owing to the racial, cultural, and political perceptions which continue to linger after generations of enforced racial segregation in South Africa. It is evident from the findings that perceptions pertaining to race, culture, and politics exert a significant influence on social relations in the caring for and protection of vulnerable children and on family dynamics in adoptive families. It also emerged from the findings that CRA placements have begun to decline significantly, owing to factors such as long and tedious assessment processes, the xviii attitudes of social workers, a general lack of adequate pre- and post-adoption support for adoptive parents, and shortages of adoption social work staff and resources. The researcher endeavoured to assess the roles of adoption social workers within the adoption triad with respect to determining the adoptability of children and matching them with prospective adoptive parents, recruiting and selecting prospective adoptive parents, counselling prospective parents, counselling biological parents, counselling adopted children, and the providing of post-adoption services. It could be concluded from the findings that although the practice of CRA is an efficacious and desirable form of care for children who are in need of protection, despite any present shortcomings in relation to legislation pertaining to the practice, the phenomenon requires considerably more attention from relevant academics and researchers than it has received to date. The overarching conclusion which emerged from the findings was that although the practice of CRA has attracted controversy and denunciations from several racial groups, it has unlimited potential for erasing the racial stigmas which continue to haunt South African society as well as affording permanency care to those children who are in need of it. The study ends with some recommendations as well as a conceptual framework to deal with the issues of the practices, dynamics and discourses of CRA in South Africa.
- Full Text:
- Date Issued: 2020
- Authors: Nyasha, Kausi
- Date: 2020
- Subjects: Interracial adoption -- South Africa -- Eastern Cape Adoption -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD(Social Work)
- Identifier: http://hdl.handle.net/10353/18009 , vital:42003
- Description: This study investigated the practices, dynamics, and discourses pertaining to crossracial adoption (CRA) in the Buffalo City Municipality (BCM) in South Africa. The researcher made use of qualitative methods to collect and analyse relevant data, which was made from both the in-depth interviews and focus group discussions. The research sample comprised of six adoption social workers, ten adoptive parents and ten adoptees, who were selected by means of purposive non-random sampling. The researcher also made use of observations, in order to that relevant, valuable, and rich information could be obtained. All the data was subsequently analysed by means of thematic analysis. The principal findings of the study revealed that although it has been legal since 1991, the practices of CRA in South Africa continues to be controversial and that, in the vast majority of cases, it entails black children being adopted by white parents. Relevant discourses covered cultural genocide, the best interests of adopted children, racial identity, colour-blindness, acculturation, and racial consciousness. The phenomenon of CRA needed to be evaluated from all of these standpoints, owing to the racial, cultural, and political perceptions which continue to linger after generations of enforced racial segregation in South Africa. It is evident from the findings that perceptions pertaining to race, culture, and politics exert a significant influence on social relations in the caring for and protection of vulnerable children and on family dynamics in adoptive families. It also emerged from the findings that CRA placements have begun to decline significantly, owing to factors such as long and tedious assessment processes, the xviii attitudes of social workers, a general lack of adequate pre- and post-adoption support for adoptive parents, and shortages of adoption social work staff and resources. The researcher endeavoured to assess the roles of adoption social workers within the adoption triad with respect to determining the adoptability of children and matching them with prospective adoptive parents, recruiting and selecting prospective adoptive parents, counselling prospective parents, counselling biological parents, counselling adopted children, and the providing of post-adoption services. It could be concluded from the findings that although the practice of CRA is an efficacious and desirable form of care for children who are in need of protection, despite any present shortcomings in relation to legislation pertaining to the practice, the phenomenon requires considerably more attention from relevant academics and researchers than it has received to date. The overarching conclusion which emerged from the findings was that although the practice of CRA has attracted controversy and denunciations from several racial groups, it has unlimited potential for erasing the racial stigmas which continue to haunt South African society as well as affording permanency care to those children who are in need of it. The study ends with some recommendations as well as a conceptual framework to deal with the issues of the practices, dynamics and discourses of CRA in South Africa.
- Full Text:
- Date Issued: 2020
Use of eco-art education in supporting the establishment of sustainability competencies in basic education: an interventionist case study
- Authors: Da Silva, Juliana Schmidt
- Date: 2020
- Subjects: Environment (Art) , Environmental education -- Brazil , Sustainable development -- Brazil , Education -- Curricula -- Brazil , Eco-art education
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/166127 , vital:41331
- Description: Recent socioecological approaches in Environmental Education acknowledge the complexity of “real-world situations”, which include environmental problems. One response to the challenge of enabling people to develop sustainability is the key competencies in sustainability framework. It can be faced as a guide to planning Environmental Education actions. On the other side, art practices hold potential to expand learning in varied ways. Art can offer the strategies employed in learning processes directed to sustainability, constituting the field of eco-art education. This research aims to investigate the integration of the visions of the key competencies in sustainability and the eco-art education in an Environmental Education project at high school level. Horta and Gastronomia (Vegetable Garden and Gastronomy) is an extra-curricular activity which happens every year at Irmão Jaime Biazus high school in Porto Alegre, Brazil. It addresses food security and sustainability associating the garden, the kitchen and exploration of sustainability issues using eco-art strategies. Action research approach is used, defining two research cycles to explore the effectiveness of eco-art for the development of key competencies in sustainability. The first cycle focuses on the eco-art activities applied in Horta and Gastronomia (2017 group) while the second cycle deals with a post-project intervention designed to observe indicators of the sustainability competencies and further explore eco-art strategies. This study adds to the field of sustainability competencies by exploring teaching strategies through eco-art education. Insight into key competencies in sustainability is given by presenting the investigation of the group of students about a situation of their reality. The activities implemented, classified according to their objectives, are contextualized regarding the competencies and in learning sequences. This research also contributes to the development of the sustainability competencies framework by applying the theory to a basic education level, adapting the work originally proposed to higher education contexts.
- Full Text:
- Date Issued: 2020
- Authors: Da Silva, Juliana Schmidt
- Date: 2020
- Subjects: Environment (Art) , Environmental education -- Brazil , Sustainable development -- Brazil , Education -- Curricula -- Brazil , Eco-art education
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/166127 , vital:41331
- Description: Recent socioecological approaches in Environmental Education acknowledge the complexity of “real-world situations”, which include environmental problems. One response to the challenge of enabling people to develop sustainability is the key competencies in sustainability framework. It can be faced as a guide to planning Environmental Education actions. On the other side, art practices hold potential to expand learning in varied ways. Art can offer the strategies employed in learning processes directed to sustainability, constituting the field of eco-art education. This research aims to investigate the integration of the visions of the key competencies in sustainability and the eco-art education in an Environmental Education project at high school level. Horta and Gastronomia (Vegetable Garden and Gastronomy) is an extra-curricular activity which happens every year at Irmão Jaime Biazus high school in Porto Alegre, Brazil. It addresses food security and sustainability associating the garden, the kitchen and exploration of sustainability issues using eco-art strategies. Action research approach is used, defining two research cycles to explore the effectiveness of eco-art for the development of key competencies in sustainability. The first cycle focuses on the eco-art activities applied in Horta and Gastronomia (2017 group) while the second cycle deals with a post-project intervention designed to observe indicators of the sustainability competencies and further explore eco-art strategies. This study adds to the field of sustainability competencies by exploring teaching strategies through eco-art education. Insight into key competencies in sustainability is given by presenting the investigation of the group of students about a situation of their reality. The activities implemented, classified according to their objectives, are contextualized regarding the competencies and in learning sequences. This research also contributes to the development of the sustainability competencies framework by applying the theory to a basic education level, adapting the work originally proposed to higher education contexts.
- Full Text:
- Date Issued: 2020
A formative intervention study of how learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia
- Authors: Shipopyeni, Salomo S M
- Date: 2020
- Subjects: Education, Secondary -- Namibia , Student government -- Namibia -- Case studies , Student participation in administration -- Namibia -- Case studies
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144934 , vital:38393
- Description: The Namibian Education system, after the country gained independence, introduced various reforms to ensure the attainment of the educational goals of access, quality, equity and democracy in schools. One of the policies introduced to promote democracy in our schools was The Educational Act 16 of 2001, which gave birth to the establishment of Learners Representatives Councils (LRC) in schools. The LRC body is the legal learner leadership body established to ensure learners are represented in school leadership. However, various studies have revealed that this legal body of learners in many schools has been merely ‘rubber-stamping’ decisions made by teachers; learners have had very little input in decisions that affect them as learners. Thus, I was prompted to conduct this formative intervention study on learner leadership at an urban combined school in Namibia. Informed by distributed and transformative leadership theories, the study aimed to develop leadership within the LRC members and the needed expansive transformation regarding leadership practices in school. The intention was for learners to be enabled to practice their democratic right in decision-making processes in matters that concerned their schooling and learning. This study was theoretically and analytically framed by second generation CulturalHistorical Activity Theory. The participants included 12 LRC members, the LRC liaison teacher, the class register teacher, three school management team members and the principal. The research method was a case study, underpinned by the critical paradigm to bring about the fundamental expansive transformation in learner leadership practices at the case study school. This qualitative study was divided into two phases, a contextual profiling phase and an intervention phase. Data were generated through document analysis, observation, questionnaires, focus group interviews and Change Laboratory Workshops. The data were generated to answer the over-arching question: How learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia. The data were analysed inductively and abductively. The key findings were: first, there were a variety of understandings of the concept learner leadership; second, the involvement of LRC members in decision-making processes was limited to involvement in organising extracurricular activities and controlling of other learners at school; third, leadership development opportunities for learners at the case study school were only provided through training at the beginning of the year and the LRC carrying out various activities and roles at the case study school. Several challenges that constrained the LRC voice and leadership development were surfaced and, through Change Laboratory Workshops, the participants of the activity system together with me (the researcher-interventionist), identified the expansive learning opportunities to develop leadership amongst Learner Representative Council (LRC) members. In the final analysis, this study will contribute to the production of knowledge on the concept of learner leadership in the context of Namibia. Fellow scholars, professionals, colleagues and policy makers in education are requested to engage with this thesis to contribute to our understanding of this important aspect of our field and speak back to policy.
- Full Text:
- Date Issued: 2020
- Authors: Shipopyeni, Salomo S M
- Date: 2020
- Subjects: Education, Secondary -- Namibia , Student government -- Namibia -- Case studies , Student participation in administration -- Namibia -- Case studies
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144934 , vital:38393
- Description: The Namibian Education system, after the country gained independence, introduced various reforms to ensure the attainment of the educational goals of access, quality, equity and democracy in schools. One of the policies introduced to promote democracy in our schools was The Educational Act 16 of 2001, which gave birth to the establishment of Learners Representatives Councils (LRC) in schools. The LRC body is the legal learner leadership body established to ensure learners are represented in school leadership. However, various studies have revealed that this legal body of learners in many schools has been merely ‘rubber-stamping’ decisions made by teachers; learners have had very little input in decisions that affect them as learners. Thus, I was prompted to conduct this formative intervention study on learner leadership at an urban combined school in Namibia. Informed by distributed and transformative leadership theories, the study aimed to develop leadership within the LRC members and the needed expansive transformation regarding leadership practices in school. The intention was for learners to be enabled to practice their democratic right in decision-making processes in matters that concerned their schooling and learning. This study was theoretically and analytically framed by second generation CulturalHistorical Activity Theory. The participants included 12 LRC members, the LRC liaison teacher, the class register teacher, three school management team members and the principal. The research method was a case study, underpinned by the critical paradigm to bring about the fundamental expansive transformation in learner leadership practices at the case study school. This qualitative study was divided into two phases, a contextual profiling phase and an intervention phase. Data were generated through document analysis, observation, questionnaires, focus group interviews and Change Laboratory Workshops. The data were generated to answer the over-arching question: How learner voice and leadership can be developed within a Learner Representative Council (LRC) in an urban combined school, Namibia. The data were analysed inductively and abductively. The key findings were: first, there were a variety of understandings of the concept learner leadership; second, the involvement of LRC members in decision-making processes was limited to involvement in organising extracurricular activities and controlling of other learners at school; third, leadership development opportunities for learners at the case study school were only provided through training at the beginning of the year and the LRC carrying out various activities and roles at the case study school. Several challenges that constrained the LRC voice and leadership development were surfaced and, through Change Laboratory Workshops, the participants of the activity system together with me (the researcher-interventionist), identified the expansive learning opportunities to develop leadership amongst Learner Representative Council (LRC) members. In the final analysis, this study will contribute to the production of knowledge on the concept of learner leadership in the context of Namibia. Fellow scholars, professionals, colleagues and policy makers in education are requested to engage with this thesis to contribute to our understanding of this important aspect of our field and speak back to policy.
- Full Text:
- Date Issued: 2020
An historical analysis of the development of a company as a single enterprise and the impact on group company taxation
- Authors: Els, Tania
- Date: 2020
- Subjects: Taxation -- South Africa , Taxation -- History , Taxation -- Law and legislation -- South Africa , Business enterprises -- South Africa , Business enterprises -- Taxation -- Law and legislation -- South Africa , Corporation law -- South Africa , South Africa. Income Tax Act, 1962 , South Africa. Companies Act, 2008 , Separate legal personality , Group taxation
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/154241 , vital:39628
- Description: The company is considered a separate legal entity in both legislation and jurisprudence. The “veil” separating the company and its shareholders is a doctrine entrenched in company law that originated centuries ago. The doctrine is based on conditions that existed during a period that commenced with trading forms less complicated than the corporate groups found today. Trading forms known as guilds could be traced back to 1087, which gradually developed into regulated companies and, in the last century, into the joint-stock company form. The modern era has seen the development of groups of companies carrying on business as economic units. Company law, in regulating business forms, has failed to acknowledge the corporate group as a new business entity. The main purpose of this research was to analyse the origins of the separate legal personality of a company and its relevance for the present corporate group structures. The research aimed to understand company law and jurisprudence in South Africa in relation to the legal personality of a company and a corporate group. The final objective of this reform-orientated doctrinal research thesis was to provide clarity on the need to consider granting separate legal identity to corporate groups in recognition of their economic unity. A historically contextualised analysis was carried out on the development of trading through unregulated forms of businesses to the creation of the company as a regulated entity. The development of the legal persona of a company in legislation as well as jurisprudence was critically analysed in on the context of companies within a corporate group. A case study of a South African corporate group was used to highlight the different characteristics of the companies doing business in the form of a corporate group. The thesis concluded by recommending that legal personality should be extended to include a corporate group in order to facilitate the introduction of a group taxation regime.
- Full Text:
- Date Issued: 2020
- Authors: Els, Tania
- Date: 2020
- Subjects: Taxation -- South Africa , Taxation -- History , Taxation -- Law and legislation -- South Africa , Business enterprises -- South Africa , Business enterprises -- Taxation -- Law and legislation -- South Africa , Corporation law -- South Africa , South Africa. Income Tax Act, 1962 , South Africa. Companies Act, 2008 , Separate legal personality , Group taxation
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/154241 , vital:39628
- Description: The company is considered a separate legal entity in both legislation and jurisprudence. The “veil” separating the company and its shareholders is a doctrine entrenched in company law that originated centuries ago. The doctrine is based on conditions that existed during a period that commenced with trading forms less complicated than the corporate groups found today. Trading forms known as guilds could be traced back to 1087, which gradually developed into regulated companies and, in the last century, into the joint-stock company form. The modern era has seen the development of groups of companies carrying on business as economic units. Company law, in regulating business forms, has failed to acknowledge the corporate group as a new business entity. The main purpose of this research was to analyse the origins of the separate legal personality of a company and its relevance for the present corporate group structures. The research aimed to understand company law and jurisprudence in South Africa in relation to the legal personality of a company and a corporate group. The final objective of this reform-orientated doctrinal research thesis was to provide clarity on the need to consider granting separate legal identity to corporate groups in recognition of their economic unity. A historically contextualised analysis was carried out on the development of trading through unregulated forms of businesses to the creation of the company as a regulated entity. The development of the legal persona of a company in legislation as well as jurisprudence was critically analysed in on the context of companies within a corporate group. A case study of a South African corporate group was used to highlight the different characteristics of the companies doing business in the form of a corporate group. The thesis concluded by recommending that legal personality should be extended to include a corporate group in order to facilitate the introduction of a group taxation regime.
- Full Text:
- Date Issued: 2020
Perceptions of health care professionals at the Nelson Mandela University of the Auntie Stella sexual and reproductive health education toolkit
- Authors: Ndlangalavu, Siyasanga
- Date: 2020
- Subjects: Sexual health
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46419 , vital:39589
- Description: Sexual and reproductive health education in South Africa appears to be failing young people as evidenced by the numbers of unplanned pregnancies and sexually transmitted diseases resulting from poor sexual health decision making. High-risk behaviours amongst youth are likely to be a product of the interplay of multiple risk factors on individual and interpersonal levels. The Auntie Stella: Teenagers Talk about Sex, Life and Relationships, is a sexual and reproductive health education toolkit with developmentally timed interventions for sexual and reproductive health education for adolescents. This tool kit has been successfully utilized in such countries as Zimbabwe, Tanzania, Malawi, Mozambique and Zambia. The study aimed to establish if the University health care professionals, including HIV counsellors and nurses, perceive Auntie Stellato be a useful sexual health and reproduction education programme to generate knowledge and prompt and promote safer sexual behaviour. An exploratory descriptive qualitative research design was be utilized, and purposive sampling was employed. Data was collected via focus groups where the toolkit was administered and discussed. Six focus groups were conducted with 12 participants from the Nelson Mandela University’s Campus Health Clinics. The data obtained was analyzed using Braun and Clarke’s (2006) six-step method of thematic analysis. The findings of this study revealed that the Nelson Mandela University health care professionals perceived the Auntie Stellatoolkit as being useful and applicable to the university context in terms of relatability. They expressed thatthe programme is ideally youth-friendly and appropriate for university students. The findings of this small study may have important implications for future research of implementation of sexual and reproductive health education programmes in Higher Education Institutions.
- Full Text:
- Date Issued: 2020
- Authors: Ndlangalavu, Siyasanga
- Date: 2020
- Subjects: Sexual health
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46419 , vital:39589
- Description: Sexual and reproductive health education in South Africa appears to be failing young people as evidenced by the numbers of unplanned pregnancies and sexually transmitted diseases resulting from poor sexual health decision making. High-risk behaviours amongst youth are likely to be a product of the interplay of multiple risk factors on individual and interpersonal levels. The Auntie Stella: Teenagers Talk about Sex, Life and Relationships, is a sexual and reproductive health education toolkit with developmentally timed interventions for sexual and reproductive health education for adolescents. This tool kit has been successfully utilized in such countries as Zimbabwe, Tanzania, Malawi, Mozambique and Zambia. The study aimed to establish if the University health care professionals, including HIV counsellors and nurses, perceive Auntie Stellato be a useful sexual health and reproduction education programme to generate knowledge and prompt and promote safer sexual behaviour. An exploratory descriptive qualitative research design was be utilized, and purposive sampling was employed. Data was collected via focus groups where the toolkit was administered and discussed. Six focus groups were conducted with 12 participants from the Nelson Mandela University’s Campus Health Clinics. The data obtained was analyzed using Braun and Clarke’s (2006) six-step method of thematic analysis. The findings of this study revealed that the Nelson Mandela University health care professionals perceived the Auntie Stellatoolkit as being useful and applicable to the university context in terms of relatability. They expressed thatthe programme is ideally youth-friendly and appropriate for university students. The findings of this small study may have important implications for future research of implementation of sexual and reproductive health education programmes in Higher Education Institutions.
- Full Text:
- Date Issued: 2020
The past meets the present: exploring the biogeography of extant plecoptera of South Africa with reference to ancient middle permian fossil forms from the Onder Karoo locality near Sutherland
- Authors: Kirkaldy, Benjamin Puleng
- Date: 2020
- Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/165755 , vital:41278
- Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
- Full Text:
- Date Issued: 2020
- Authors: Kirkaldy, Benjamin Puleng
- Date: 2020
- Subjects: Stoneflies, Fossil -- South Africa -- Northern Cape , Palaeopteron -- South Africa -- Northern Cape , Stoneflies -- Evolution , Insects, Fossil -- South Africa -- Northern Cape , Paleoentomology , Paleoentomology -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/165755 , vital:41278
- Description: The Onder Karoo fossil locality near Sutherland, Northern Cape, recently yielded an unprecedented diversity of middle Permian insects, which were preserved in deposits of an aquatic lake margin system, in the Lowermost Abrahamskraal Formation. A large number of Plecoptera (stonefly) specimens were found, and this study represents an in-depth analysis of these species in the context of plecopteran evolution. A significant contribution to current knowledge of the Plecoptera from the middle Permian to the present has been made, utilizing a combination of fossil and phylogenetic evidence to better understand the origins, evolution, diversity and biogeography of the stoneflies. Three new plecopteran species have been described from the Onder Karoo locality, which is recognized here as the first Lagerstätte of its kind in Gondwana. Possible ecological links and relationships with the plecopterans described here have been suggested, using extant Plecoptera as analogues. An in-depth, fossilcalibrated, dated phylogeny of the Plecoptera was completed, using representatives from all three dominant lineages, the Antarctoperlaria, Systellognatha and the Euholognatha. This provides strong support for the monophyly of the Notonemouridae and the Antarctoperlaria, however the monophyly of Systellognatha and Euholognatha was not supported. The Notonemouridae were found to represent an earlier divergence than previously believed, forming a sister group to the remaining Plecoptera. Through a combination of fossil and molecular evidence, strong support was found for the current distribution of the Plecoptera worldwide being attributable to vicariance caused by the rifting of Pangea, and subsequently Gondwana and Laurasia, and long range dispersal. The focussed effort to include Southern Hemisphere stoneflies throughout this study has been a valuable step in reducing the Northern Hemisphere bias which currently dominates plecopteran research and has assisted in opening the way for future research into this important group on a global scale.
- Full Text:
- Date Issued: 2020
Combining DNA barcoding and morphology to identify larval fishes from the nearshore environment off the south-east coast of South Africa
- Authors: Somana, Zinzi Sinazo
- Date: 2020
- Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144605 , vital:38362
- Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
- Full Text:
- Date Issued: 2020
- Authors: Somana, Zinzi Sinazo
- Date: 2020
- Subjects: Fishes -- Larvae -- South Africa -- Identification , Fishes -- Genetics -- Research -- Technique , Fishes -- South Africa -- Classification , Genetic markers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/144605 , vital:38362
- Description: The early life history stages of most marine fish species are undescribed. The problem is, most of these fishes have pelagic larvae which are minute, delicate forms. Linking the larval stage to an adult counterpart is extremely challenging as larvae are morphologically different from the adults. Historically, larval fish identification relied solely on distinguishing morphological characteristics and meristic measurements, which has resulted in taxonomic confusion and misidentification. The introduction of the deoxyribonucleic acid (DNA) barcoding technique as an alternative approach has been successful in positively identifying larval fishes. The correct identification of larval specimens is the key to a better understanding of larval ecology, which underpins the success of any adult fish population. This study aimed to positively identify larval fishes of the south-east coast of South Africa using morphological characteristics and DNA barcoding. Larval and eggs specimens for this study were collected from the shallow nearshore waters of the south-east coast of South Africa. A total of 177 larval specimens were used for morphological analysis. Body shape, gut shape, pigmentation and morphometric measurements (such as body depth, preanal length and total body length) were used to identify each specimen to the family level. In addition, a fragment of mitochondrial cytochrome c oxidase subunit 1 gene (COI) was adopted for sequencing to identify larval fish specimens and fish eggs. Sequences generated from this study were compared to those in the Barcode of Life Database (BOLD). When there were no close matches to a sequence, the GenBank nucleic acid sequence database, maintained by the National Center for Biotechnology Information (NCBI), was used as an alternative. A total of 18 different families were identified through morphology. Seventy-seven of the 177 larval specimens were not subjected to morphological identification due to physical damage. The majority of larvae identified using morphological characteristics belonged to either the Sparidae, Tripterygiidae or Gobiesocidae fish families. Through DNA barcoding, 12 fish families, 16 genera and 18 different species were identified. Ten DNA barcodes (categorised as ‘no match’) from 10 different larval specimens were not identified through any of the online databases. Therefore, the 2% threshold value was used to identify members of the same species. The K2P genetic distance relationships were calculated among the no match sequences and downloaded probability matches from NCBI. This resulted in two unknown specimens assigned to the Blenniidae and Gobiidae. All other taxa were identified to species level, except specimens representing the Gobiidae and Tripterygiidae families. Based on the K2P genetic distances Gobiidae representatives were categorised as members of the Caffrogobius genus. Twenty-eight barcodes represented specimens from the Tripterygiidae. DNA barcode data from COI was analysed using the standard phylogenetic procedures in MEGA6 to examine relationships and differentiation among sequences. These could not be identified to the lowest taxonomic rank due to limited sequence data to compare them with. The sequence data from these specimens gave different results in the two online databases. BOLD results were to family level (Tripterygiidae) and NCBI to the species level (Clinidae: Pavoclinus profundus). Results in this study confirmed the efficiency of the DNA barcoding technique in species level identification of fish larvae. The evidence from genetic barcodes of the Tripterygiidae specimens, supported by morphological characteristics, suggests the need for thorough research to identify the individuals to the species level. The fact that this study identified taxonomically problematic Gobiidae and Tripterygiidae specimens suggests that studies similar to this may highlight additional diversity and help to resolve the taxonomy of other species in these families. However, the lack of reference sequence data from the adult specimens, and especially those with cryptic diversity, were both shortcomings for the positive identification of larvae. With that being said, it shows the necessity for more research to be conducted on barcoding of larvae in general as to accommodate all kinds of species from biodiversity to economic perspectives.
- Full Text:
- Date Issued: 2020
The impact of discounting fees by civil engineering consultants
- Authors: Siqiti, Khulile
- Date: 2020
- Subjects: Consulting engineers , Consultants Civil engineering , Project management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47246 , vital:39836
- Description: The study provides insight into the views and perceptions of consulting engineers on the discounting of professional fees. The purpose of the research was to determine the impact of discounting professional fees in the civil engineering profession and ultimately potential ways in which the civil engineering profession could improve business sustainability. The study included a review of literature, which was utilised to develop a questionnaire. A total of 26 practicing consulting engineers, who are members of Consulting Engineers South Africa (CESA), and represented small, medium and large consulting engineering firms, participated in the questionnaire survey. The questionnaire investigates the respondents’ perceptions on the impact of discounting professional fees in the civil engineering profession and the amount of discount offered as well as the reasons for discounting fees. The results show that the practice of discounting professional fees is widespread, affecting small, medium and large consulting firms. The results also indicate that prevailing market conditions in civil engineering profession are the primary reasons why consulting engineers offer discounts on fees. Respondents agreed that projects are awarded to the lowest bidder during tender process. Respondents also agreed that experienced engineers are allocated less time on projects to manage project costs. The findings suggest that discounting of professional fees is a great concern that needs to be addressed in order to attain profession business sustainability. It is suggested that the Engineering Council of South Africa (ECSA) should regulate the fee structures and ensure that all professionals, whether employed in the public or private sector, understand the basic finances on running a professional consultancy to deliver a service.
- Full Text:
- Date Issued: 2020
- Authors: Siqiti, Khulile
- Date: 2020
- Subjects: Consulting engineers , Consultants Civil engineering , Project management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/47246 , vital:39836
- Description: The study provides insight into the views and perceptions of consulting engineers on the discounting of professional fees. The purpose of the research was to determine the impact of discounting professional fees in the civil engineering profession and ultimately potential ways in which the civil engineering profession could improve business sustainability. The study included a review of literature, which was utilised to develop a questionnaire. A total of 26 practicing consulting engineers, who are members of Consulting Engineers South Africa (CESA), and represented small, medium and large consulting engineering firms, participated in the questionnaire survey. The questionnaire investigates the respondents’ perceptions on the impact of discounting professional fees in the civil engineering profession and the amount of discount offered as well as the reasons for discounting fees. The results show that the practice of discounting professional fees is widespread, affecting small, medium and large consulting firms. The results also indicate that prevailing market conditions in civil engineering profession are the primary reasons why consulting engineers offer discounts on fees. Respondents agreed that projects are awarded to the lowest bidder during tender process. Respondents also agreed that experienced engineers are allocated less time on projects to manage project costs. The findings suggest that discounting of professional fees is a great concern that needs to be addressed in order to attain profession business sustainability. It is suggested that the Engineering Council of South Africa (ECSA) should regulate the fee structures and ensure that all professionals, whether employed in the public or private sector, understand the basic finances on running a professional consultancy to deliver a service.
- Full Text:
- Date Issued: 2020
Exploring the psychosocial effects of removing teenagers from their homes to places of safety
- Authors: Boxongo , Sisipho
- Date: 2020
- Subjects: Teenagers
- Language: English
- Type: Thesis , Masters , MSW
- Identifier: http://hdl.handle.net/10353/18073 , vital:42226
- Description: The child welfare system investigate over 2 Million children each year for parental abuse or neglect, yet little is known about the psychosocial effects of removing teenagers from their homes and placing them in the place of safety. Although an abusive family would undoubtedly be harmful to children, removing a child from his or her family can be just as traumatic. Long term outcome are rarely observed, and teenagers placed in the place of safety are likely differ from those not placed. Hence this study took a microscopic scrutiny at the effects of the teenager`s removal from their home environment to a place of safety. In carrying out this research qualitative method of data collection was used. The study outlined the factors that lead to removal of teenagers from their home environment to the place of safety. The study found that some of the teenagers who were removed from their home environment were due to poverty, maltreatment, negligence and child abuse at home. The study also revealed that the placement of the teenagers in the places of safety expose the teenagers to psychological, physical, emotional and behavioural negative experiences. The teenagers that participated in the study mentioned that they are stigmatised by the community and peers at school, some also cited that they have lost contact with their families. It was also found out that; the professionals who participated in the study also too experience some challenges in rendering services to the teenagers as sometimes they don`t get informed about the children`s situation on their arrival in the centre. On the other hand, another professional declared that they are trying by all means to cater for all the needs of the children, but they are failed by the case managers and other stakeholders, such as department of social development who delay the process of obtaining court orders which makes it difficult for the child to be funded and also the process of reunifying the child with the biological family.
- Full Text:
- Date Issued: 2020
- Authors: Boxongo , Sisipho
- Date: 2020
- Subjects: Teenagers
- Language: English
- Type: Thesis , Masters , MSW
- Identifier: http://hdl.handle.net/10353/18073 , vital:42226
- Description: The child welfare system investigate over 2 Million children each year for parental abuse or neglect, yet little is known about the psychosocial effects of removing teenagers from their homes and placing them in the place of safety. Although an abusive family would undoubtedly be harmful to children, removing a child from his or her family can be just as traumatic. Long term outcome are rarely observed, and teenagers placed in the place of safety are likely differ from those not placed. Hence this study took a microscopic scrutiny at the effects of the teenager`s removal from their home environment to a place of safety. In carrying out this research qualitative method of data collection was used. The study outlined the factors that lead to removal of teenagers from their home environment to the place of safety. The study found that some of the teenagers who were removed from their home environment were due to poverty, maltreatment, negligence and child abuse at home. The study also revealed that the placement of the teenagers in the places of safety expose the teenagers to psychological, physical, emotional and behavioural negative experiences. The teenagers that participated in the study mentioned that they are stigmatised by the community and peers at school, some also cited that they have lost contact with their families. It was also found out that; the professionals who participated in the study also too experience some challenges in rendering services to the teenagers as sometimes they don`t get informed about the children`s situation on their arrival in the centre. On the other hand, another professional declared that they are trying by all means to cater for all the needs of the children, but they are failed by the case managers and other stakeholders, such as department of social development who delay the process of obtaining court orders which makes it difficult for the child to be funded and also the process of reunifying the child with the biological family.
- Full Text:
- Date Issued: 2020
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:
- Date Issued: 2020
- 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:
- Date Issued: 2020
A holistic approach in understanding the effects of dietary protein sources on the growth and reproductive development of farmed abalone, Haliotis midae
- Wu, Yu
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- Full Text:
- Date Issued: 2020
- Authors: Wu, Yu
- Date: 2020
- Subjects: Abalones -- Nutrition , Abalones -- Reproduction , Abalones -- Growth , Abalone culture , Haliotis midae -- Nutrition , Haliotis midae -- Reproduction , Haliotis midae -- Growth , Haliotis midae fisheries
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167719 , vital:41506
- Description: The combination of fishmeal and soya in the formulated feed of farmed South African abalone, Haliotis midae, not only improved abalone growth, but also the sustainability of the compound diets by reducing the reliance on fishmeal. However, the presence of soya produced larger gonads compared to those of abalone fed kelp or single-source protein diets. There is an increasing drive to control sexual maturation and reduce undesirable spawning events in farmed abalone. However, the reasons for the reported effects of soya inclusion on the reproductive development of farmed H. midae remain unresolved. The aim of this research was to use a combination of techniques to contribute to the understanding of the relationship between growth, reproductive and nutritional physiology of farmed H. midae fed diets of varying protein sources. These techniques included stable isotope analysis (SIA), fatty acid analysis, gonad histological assessments and haemolymph sexsteroid hormone analysis. The objectives were to examine the allocation of protein and nutritional components to somatic and reproductive tissues. This study also included the first attempt to investigate the role that sex steroid hormones play during gametogenesis. Abalone (40 – 50 g abalone-1) were fed one of four diets: either a single-source protein-based diet, i.e., (1) fishmeal-only (FM) or (2) soya-only (S), or a combination diet of (3) fishmeal-soya (FM S) or (4) fishmeal-sunflower meal (FM SM). Sampling occurred in 45-day intervals over one year. Dietary protein source had an effect on the growth of abalone, with enhancements in growth linked to the combination of fishmeal and a plant-protein source. The fishmeal ingredient was the most utilised protein source throughout the temporal changes in protein allocation into somatic and reproductive tissue, followed by soya and then sunflower meal. The mean whole- body mass of abalone was significantly influenced by an interaction between time and dietary treatment, with average whole-body mass changing differently over time between treatments (RM-ANOVA, F(24, 96) = 2.13, p = 0.005). Overall, abalone that were fed FM S had higher mean whole-body mass values than abalone that were fed the single-protein based diets, while abalone that were fed FM SM were similar to animals from all dietary treatments (RMANOVA, F(3, 12) = 5.75, p = 0.01). Male abalone had significantly higher gonad bulk index (GBI) values compared to females (RM-ANOVA, F(1, 24) = 49.03, p < 0.001) and this was independent of dietary treatment. Within each sex, female abalone fed the FM S diet (15.92 ± 1.88 mm3 g-1) had significantly higher GBI values than abalone fed S (9.76 ± 1.08 mm3 g-1), while abalone fed FM (11.96 ± 1.71 mm3 g-1) and FM SM (11.90 ± 0.80 mm3 g-1) were similar to abalone from all other dietary treatments (Tukey’s HSD, p < 0.05). Male abalone fed the FM S (21.59 ± 2.10 mm3 g-1) and FM SM diet (19.30 ± 2.63 mm3 g-1) had similar GBI values and they were significantly higher than in abalone fed the S diet (14.74 ± 1.27 mm3 g-1), while abalone fed FM S had significantly higher GBI values than abalone that consumed the FM diet (15.08 ±1.63mm3 g-1) ( Tukey’s HSD, p < 0.05). Although sunflower meal was poorly utilised, it produced similar overall growth to abalone that were fed the FM S diets. Yet, feed conversion ratio values were significantly lower for abalone fed FM S (1.30 ± 0.13) compared to those in the other three treatments, with ratios ranging from 1.65 – 1.72 over the one-year. The fatty acid compositions of the somatic and gonadal tissues were similar between treatments (PERMANOVA, p = 0.21), while fatty acid composition was influenced by sampling day, tissue type and abalone sex (PERMANOVA, p < 0.05). The essential fatty acids (EFAs) eicosadienoic acid and a-linolenic acid were present in abalone tissue, but they were not detected in the diets, suggesting the important role that an alternate food source (e.g. farmed abalone also had access to diatoms) may have played and the ability that H. midae may have in converting long-chain polyunsaturated fatty acids from C18 precursors. A change in the abundance of EFAs in the gonad tissue during highest and lowest GBI values suggested that arachidonic, eicosapentaenoic, g-linolenic and linoleic acid were important in females, while eicosapentaenoic, eicosadienoic and a-linolenic acid were important for male reproductive development. Dietary protein sources had an effect on the frequency distribution of maturity stages, where females that were fed FM S produced more ripe gonads and more males that were fed FM SM contained testes that showed signs of ripeness over the one-year study. Although dietary protein influenced the sex steroid concentrations in females and males, exhibiting fluctuations throughout the one-year period, no distinct pattern linked to gametogenesis were observed. The results from this study illustrate: (1) the importance of conducting laboratory studies when implementing SIA and mixing models in aquaculture nutrition; (2) conducting nutritional studies on mature, grow-out abalone; and (3) assessing the importance of naturally occurring diatoms in their diet and their contribution to growth and reproduction. The novel contribution of this research towards abalone nutritional physiology, the implications of these findings to industry as well as potential considerations for future studies were addressed.
- Full Text:
- Date Issued: 2020
Developing a Machine Learning Algorithm for Outdoor Scene Image Segmentation
- Authors: Zangwa, Yamkela
- Date: 2020
- Subjects: Computational intelligence Computer science
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12087 , vital:39150
- Description: Image segmentation is one of the major problems in image processing, computer vision and machine learning fields. The main reason for image segmentation existence is to reduce the gap between computer vision and human vision by training computers with different data. Outdoor image segmentation and classification has become very important in the field of computer vision with its applications in woodland-surveillance, defence and security. The task of assigning an input image to one class from a fixed set of categories seem to be a major problem in image segmentation. The main question that has been addressed in this research is how outdoor image classification algorithms can be improved using Region-based Convolutional Neural Network (R-CNN) architecture. There has been no one segmentation method that works best on any given problem. To determine the best segmentation method for a certain dataset, various tests have to be done in order to achieve the best performance. However deep learning models have often achieved increasing success due to the availability of massive datasets and the expanding model depth and parameterisation. In this research Convolutional Neural Network architecture is used in trying to improve the implementation of outdoor scene image segmentation algorithms, empirical research method was used to answer questions about existing image segmentation algorithms and the techniques used to achieve the best performance. Outdoor scene images were trained on a pre-trained region-based convolutional neural network with Visual Geometric Group-16 (VGG-16) architecture. A pre-trained R-CNN model was retrained on five different sample data, the samples had different sizes. Sample size increased from sample one to five, to increase the size on the last two samples the data was duplicated. 21 test images were used to evaluate all the models. Researchers has shown that deep learning methods perform better in image segmentation because of the increase and availability of datasets. The duplication of images did not yield the best results; however, the model performed well on the first three samples.
- Full Text:
- Date Issued: 2020
- Authors: Zangwa, Yamkela
- Date: 2020
- Subjects: Computational intelligence Computer science
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12087 , vital:39150
- Description: Image segmentation is one of the major problems in image processing, computer vision and machine learning fields. The main reason for image segmentation existence is to reduce the gap between computer vision and human vision by training computers with different data. Outdoor image segmentation and classification has become very important in the field of computer vision with its applications in woodland-surveillance, defence and security. The task of assigning an input image to one class from a fixed set of categories seem to be a major problem in image segmentation. The main question that has been addressed in this research is how outdoor image classification algorithms can be improved using Region-based Convolutional Neural Network (R-CNN) architecture. There has been no one segmentation method that works best on any given problem. To determine the best segmentation method for a certain dataset, various tests have to be done in order to achieve the best performance. However deep learning models have often achieved increasing success due to the availability of massive datasets and the expanding model depth and parameterisation. In this research Convolutional Neural Network architecture is used in trying to improve the implementation of outdoor scene image segmentation algorithms, empirical research method was used to answer questions about existing image segmentation algorithms and the techniques used to achieve the best performance. Outdoor scene images were trained on a pre-trained region-based convolutional neural network with Visual Geometric Group-16 (VGG-16) architecture. A pre-trained R-CNN model was retrained on five different sample data, the samples had different sizes. Sample size increased from sample one to five, to increase the size on the last two samples the data was duplicated. 21 test images were used to evaluate all the models. Researchers has shown that deep learning methods perform better in image segmentation because of the increase and availability of datasets. The duplication of images did not yield the best results; however, the model performed well on the first three samples.
- Full Text:
- Date Issued: 2020
Defect Classification in Photovoltaic Modules through Thermal Infrared Imaging using Machine Learning
- Dunderdale, Christopher, Clohessy, C M
- Authors: Dunderdale, Christopher , Clohessy, C M
- Date: 2020
- Subjects: Photovoltaic power generation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48280 , vital:40838
- Description: As the global energy demand continues to soar, solar energy has become an attractive and environmentally conscious method to meet this demand. This study examines the use of machine learning techniques for defect detection and classification in photovoltaic systems using thermal infrared images. A deep learning and feature-based approach is also investigated for the purpose of detecting and classifying defective photovoltaic modules. The VGG-16 and MobileNet deep learning models are shown to provide good performance for the classification of defects. The scale invariant feature transform (SIFT) descriptor, combined with the random forest and support vector machine classifier, is also used to discriminate between defective and non-defective photovoltaic modules in a South African setting. The successful implementation of this approach has significant potential for cost reduction in defect classification over currently available methods.
- Full Text:
- Date Issued: 2020
- Authors: Dunderdale, Christopher , Clohessy, C M
- Date: 2020
- Subjects: Photovoltaic power generation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/48280 , vital:40838
- Description: As the global energy demand continues to soar, solar energy has become an attractive and environmentally conscious method to meet this demand. This study examines the use of machine learning techniques for defect detection and classification in photovoltaic systems using thermal infrared images. A deep learning and feature-based approach is also investigated for the purpose of detecting and classifying defective photovoltaic modules. The VGG-16 and MobileNet deep learning models are shown to provide good performance for the classification of defects. The scale invariant feature transform (SIFT) descriptor, combined with the random forest and support vector machine classifier, is also used to discriminate between defective and non-defective photovoltaic modules in a South African setting. The successful implementation of this approach has significant potential for cost reduction in defect classification over currently available methods.
- Full Text:
- Date Issued: 2020
Narratives of the commuter: experiences of commuting in the Port Elizabeth Northern Areas
- Authors: Lingham, Rochin Shelley
- Date: 2020
- Subjects: Commuters -- South Africa --Port Elizbeth , Traffic Safefty -- South Africa --Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46911 , vital:39731
- Description: Transportation is a fundamental element of human existence. As urban areas continue to grow at a rapid speed public transport increasingly takes on the role of providing citizens with access to participate in activities of the city. Research has shown that individual perception of public transport is influenced by passenger response to collective mobility when on board modes of transport. This study aimed to investigate the minibus taxi commuters’ constructions and relevance of their taxi commuting experiences in the Port Elizabeth Northern Areas. Building on existing work it asks: How do commuters in the Northern Areas of Port Elizabeth describe and narrate their taxi commuting experiences? This thesis is interested in the experience of public transport as told by those who make use of the industry. The study focuses on both commuters and drivers and the way they characterize the social experience of commuting in taxis. These individuals provide first-hand experience and insight of the industry. The purpose of this study is to foreground the voices of those who have first-hand experience of dependency on the public transport industry.It is these voices that must be heard and considered in policy formation. The study found simultaneous vulnerabilities exist between taxi drivers and taxi commuters resulting in both groups being held captive by the taxi industry.
- Full Text:
- Date Issued: 2020
- Authors: Lingham, Rochin Shelley
- Date: 2020
- Subjects: Commuters -- South Africa --Port Elizbeth , Traffic Safefty -- South Africa --Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/46911 , vital:39731
- Description: Transportation is a fundamental element of human existence. As urban areas continue to grow at a rapid speed public transport increasingly takes on the role of providing citizens with access to participate in activities of the city. Research has shown that individual perception of public transport is influenced by passenger response to collective mobility when on board modes of transport. This study aimed to investigate the minibus taxi commuters’ constructions and relevance of their taxi commuting experiences in the Port Elizabeth Northern Areas. Building on existing work it asks: How do commuters in the Northern Areas of Port Elizabeth describe and narrate their taxi commuting experiences? This thesis is interested in the experience of public transport as told by those who make use of the industry. The study focuses on both commuters and drivers and the way they characterize the social experience of commuting in taxis. These individuals provide first-hand experience and insight of the industry. The purpose of this study is to foreground the voices of those who have first-hand experience of dependency on the public transport industry.It is these voices that must be heard and considered in policy formation. The study found simultaneous vulnerabilities exist between taxi drivers and taxi commuters resulting in both groups being held captive by the taxi industry.
- Full Text:
- Date Issued: 2020
The role of flexible working in achieving a work-life balance: a case study of information technology consultants of Kestrel Business Solutions – London, United Kingdom
- Authors: Nyamujara, Tinashe
- Date: 2020
- Subjects: Kestrel Business Solutions , Flexible work arrangement -- Case studies , Work-life balance , Flexitime , Telecommunting , Telecommunting -- Case studies
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/167245 , vital:41459
- Description: This research was a Case Study on the role of Flexible Working in achieving a Work – Life Balance, based on the Information Technology Consultants of Kestrel Business Solutions – a company based in London, the United Kingdom. The study set out to determine what aspects of flexible working can reduce work - related stress; home - related stress; improve personal wellbeing; identify the pitfalls of flexible working, and to recommend mitigating actions. The literature review identified five different, but complimentary theories that included: The Spill over Theory; Balanced Theory; Resource Based Theory; Compensation Theory and the Wellness Theory to unpack and explore the concept of Work - Life Balance. The study followed a predominantly qualitative methodology approach and used thematic analysis to identify key ideas from the data. Interviews and questionnaires were used to obtain data from the respondents, in addition to being a data triangulation exercise. From a population of 10 subjects - purposeful sampling was used to select a sample of 10 respondents - made up of 3 males and 7 females. All respondents were employees of Kestrel Business Solutions. 6 respondents were interviewed and given questionnaires to fill out. 6 face to face interviews were conducted, and 6 questionnaires completed until saturation was achieved - indicating a survey response rate of 100%. The results from the data collection generally showed how aspects of flexible working like telecommuting, flexitime and homeworking ultimately helped the employees to achieve a Work-Life Balance - by primarily influencing how they balanced their work, home, and personal commitments. Importantly, the study also identified pitfalls of flexible working; like employees feeling isolated and the pressure to perform. Potential mitigating efforts identified in the study included, providing more company support and education for flexible working initiatives. The study concluded by acknowledging the limitations of the study, which included time constraints and the small population, and sample size of the study. In its conclusion, the study identified recommendations for future studies like: increasing the population and sample size, and devoting more time to the study, for more generalized and conclusive findings.
- Full Text:
- Date Issued: 2020
- Authors: Nyamujara, Tinashe
- Date: 2020
- Subjects: Kestrel Business Solutions , Flexible work arrangement -- Case studies , Work-life balance , Flexitime , Telecommunting , Telecommunting -- Case studies
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/167245 , vital:41459
- Description: This research was a Case Study on the role of Flexible Working in achieving a Work – Life Balance, based on the Information Technology Consultants of Kestrel Business Solutions – a company based in London, the United Kingdom. The study set out to determine what aspects of flexible working can reduce work - related stress; home - related stress; improve personal wellbeing; identify the pitfalls of flexible working, and to recommend mitigating actions. The literature review identified five different, but complimentary theories that included: The Spill over Theory; Balanced Theory; Resource Based Theory; Compensation Theory and the Wellness Theory to unpack and explore the concept of Work - Life Balance. The study followed a predominantly qualitative methodology approach and used thematic analysis to identify key ideas from the data. Interviews and questionnaires were used to obtain data from the respondents, in addition to being a data triangulation exercise. From a population of 10 subjects - purposeful sampling was used to select a sample of 10 respondents - made up of 3 males and 7 females. All respondents were employees of Kestrel Business Solutions. 6 respondents were interviewed and given questionnaires to fill out. 6 face to face interviews were conducted, and 6 questionnaires completed until saturation was achieved - indicating a survey response rate of 100%. The results from the data collection generally showed how aspects of flexible working like telecommuting, flexitime and homeworking ultimately helped the employees to achieve a Work-Life Balance - by primarily influencing how they balanced their work, home, and personal commitments. Importantly, the study also identified pitfalls of flexible working; like employees feeling isolated and the pressure to perform. Potential mitigating efforts identified in the study included, providing more company support and education for flexible working initiatives. The study concluded by acknowledging the limitations of the study, which included time constraints and the small population, and sample size of the study. In its conclusion, the study identified recommendations for future studies like: increasing the population and sample size, and devoting more time to the study, for more generalized and conclusive findings.
- Full Text:
- Date Issued: 2020