Family functioning and life satisfaction and happiness in South African households
- Botha, Ferdi, Booysen, Frikkie
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396048 , vital:69146 , xlink:href="https://doi.org/10.1007/s11205-013-0485-6"
- Description: Families form an integral part of society and in fostering individual well-being. Despite the acknowledged importance of family, the association between family functioning and individual well-being outcomes have remained unexplored in the current body of knowledge. This paper explores the association between family functioning and reported levels of life satisfaction and happiness in South Africa. The paper employs the Family Attachment and Changeability Index (FACI8) to measure family functioning, using data from the 2011 South African Social Attitudes Survey. Four measures of family functioning are utilised, namely the aggregate FACI8 scale, the attachment and changeability sub-scales, and family functioning type. Improvements in the level of family functioning as well as in the levels of attachment and changeability are positively associated with life satisfaction and happiness. In addition, individuals living in midrange or balanced family functioning types are more satisfied with life and happier compared to persons living in extremely or moderately dysfunctional families. The findings highlight the importance of supportive intra-family dynamics in fostering greater individual well-being. This in turn places emphasis on the investigation of likely correlates of family functioning and impact evaluations of family-focused social work interventions’ impact on family functioning as areas for future research.
- Full Text:
- Date Issued: 2014
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396048 , vital:69146 , xlink:href="https://doi.org/10.1007/s11205-013-0485-6"
- Description: Families form an integral part of society and in fostering individual well-being. Despite the acknowledged importance of family, the association between family functioning and individual well-being outcomes have remained unexplored in the current body of knowledge. This paper explores the association between family functioning and reported levels of life satisfaction and happiness in South Africa. The paper employs the Family Attachment and Changeability Index (FACI8) to measure family functioning, using data from the 2011 South African Social Attitudes Survey. Four measures of family functioning are utilised, namely the aggregate FACI8 scale, the attachment and changeability sub-scales, and family functioning type. Improvements in the level of family functioning as well as in the levels of attachment and changeability are positively associated with life satisfaction and happiness. In addition, individuals living in midrange or balanced family functioning types are more satisfied with life and happier compared to persons living in extremely or moderately dysfunctional families. The findings highlight the importance of supportive intra-family dynamics in fostering greater individual well-being. This in turn places emphasis on the investigation of likely correlates of family functioning and impact evaluations of family-focused social work interventions’ impact on family functioning as areas for future research.
- Full Text:
- Date Issued: 2014
Farmers’ awareness of climate change and variability and it’s effects on agricultural productivity: (the case of King Sabata Dalindyebo Municipalty in Eastern Cape)
- Authors: Mdoda, Lelethu
- Date: 2014
- Subjects: Agricultural productivity -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Crops and water -- South Africa -- Eastern Cape , Agricultural assistance -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11234 , http://hdl.handle.net/10353/d1021294 , Agricultural productivity -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Crops and water -- South Africa -- Eastern Cape , Agricultural assistance -- South Africa -- Eastern Cape
- Description: Climate is an important factor of agricultural productivity and many rural dwellers in developing countries depend on agriculture and are highly affected by climate change and variability. The world is currently experiencing climatic changes and variability conditions which results in high temperatures, low rainfall patterns, shortage of water and drought persistence. Climate change and variability is affecting weather patterns and shifting seasons which results in serious repercussions on smallholder farmers. Smallholder farmers are extremely vulnerable to climate change and variability because their farming and production systems are climate sensitive and are not rebound to climate stresses. These adverse effects in developing countries arise from different climate change and variability-related causes, notable extreme weather events, food security, increased health risks in agriculture from vector home diseases, and temperature-related morbidity in environments. The study was carried in King Sabata Dalindyebo Municipality in the Eastern Cape Province in South Africa. This study examines farmers’ awareness of climate change and variability and its effects on agricultural productivity in King Sabata Dalindyebo municipality using a Descriptive Statistics, Binary and Ricardian Model fitted to data from a cross-sectional survey of 200 farmers in King Sabata Dalindyebo Municipality. Both primary and secondary data was used. This research study estimates the effects of climate change and variability on King Sabata Dalindyebo agricultural productivity using a continental dimension of Ricardian analysis. Results revealed that local farmers were aware of climate change and variability and perceived changes in average temperatures and rainfall. The changes in average temperatures and rainfall had adverse effects on crop and livestock production. However, farmers’ awareness of climate change is not to an extent that they presume adaptation to climate change as a necessity and crucial. The results show that climate change and variability affects farm income and there is a non-linear relationship existing between climatic variables (temperature and precipitation) and farm income which depicts U-shaped. The study results indicated that climate change and variability affect agricultural productivity and have an effect on agricultural productivity in King Sabata Dalindyebo Municipality. In view of the research findings, several policy proposals are suggested. The study findings suggest that climate change and variability must be taken seriously and monitored. Policy makers and government officials must support farmers with information distribution,education, market access, well trained extension agents, credit and information about mitigation strategies to climate change and variability which includes institutional and technological methods, particularly smallholder farmers.
- Full Text:
- Date Issued: 2014
- Authors: Mdoda, Lelethu
- Date: 2014
- Subjects: Agricultural productivity -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Crops and water -- South Africa -- Eastern Cape , Agricultural assistance -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11234 , http://hdl.handle.net/10353/d1021294 , Agricultural productivity -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape , Crops and climate -- South Africa -- Eastern Cape , Crops and water -- South Africa -- Eastern Cape , Agricultural assistance -- South Africa -- Eastern Cape
- Description: Climate is an important factor of agricultural productivity and many rural dwellers in developing countries depend on agriculture and are highly affected by climate change and variability. The world is currently experiencing climatic changes and variability conditions which results in high temperatures, low rainfall patterns, shortage of water and drought persistence. Climate change and variability is affecting weather patterns and shifting seasons which results in serious repercussions on smallholder farmers. Smallholder farmers are extremely vulnerable to climate change and variability because their farming and production systems are climate sensitive and are not rebound to climate stresses. These adverse effects in developing countries arise from different climate change and variability-related causes, notable extreme weather events, food security, increased health risks in agriculture from vector home diseases, and temperature-related morbidity in environments. The study was carried in King Sabata Dalindyebo Municipality in the Eastern Cape Province in South Africa. This study examines farmers’ awareness of climate change and variability and its effects on agricultural productivity in King Sabata Dalindyebo municipality using a Descriptive Statistics, Binary and Ricardian Model fitted to data from a cross-sectional survey of 200 farmers in King Sabata Dalindyebo Municipality. Both primary and secondary data was used. This research study estimates the effects of climate change and variability on King Sabata Dalindyebo agricultural productivity using a continental dimension of Ricardian analysis. Results revealed that local farmers were aware of climate change and variability and perceived changes in average temperatures and rainfall. The changes in average temperatures and rainfall had adverse effects on crop and livestock production. However, farmers’ awareness of climate change is not to an extent that they presume adaptation to climate change as a necessity and crucial. The results show that climate change and variability affects farm income and there is a non-linear relationship existing between climatic variables (temperature and precipitation) and farm income which depicts U-shaped. The study results indicated that climate change and variability affect agricultural productivity and have an effect on agricultural productivity in King Sabata Dalindyebo Municipality. In view of the research findings, several policy proposals are suggested. The study findings suggest that climate change and variability must be taken seriously and monitored. Policy makers and government officials must support farmers with information distribution,education, market access, well trained extension agents, credit and information about mitigation strategies to climate change and variability which includes institutional and technological methods, particularly smallholder farmers.
- Full Text:
- Date Issued: 2014
Fathers' coping with the day-to-day stressors of living with a child on the autistic spectrum
- Authors: Hitge, Marcel
- Date: 2014
- Subjects: Autistic children , Parents of autistic children
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/8628 , vital:26414
- Description: In general there is very little research on the coping styles that the fathers of children suffering from Autistic Spectrum Disorder (ASD) use in order to cope with the day-to-day demands and stressors that result from their child‘s unique condition. The research study focuses on the fathers of children on the autistic spectrum and how they cope with the stressors resulting from their children‘s condition on daily basis. The study made use of Bronfenbrenner‘s Ecosystemic Theory of Human Development as the guiding theoretical framework in exploring and describing this specific research domain. This was a qualitative study and it was phenomenological, descriptive and analytical in nature. The reason for this was to hear the voices of the fathers and explore in-depth how they deal with the daily stressors resulting from their children‘s condition. Semi-structured interviews were utilised where the fathers were asked to respond to an open-ended question. The data that was obtained from the fathers was analysed by means of content analysis. The sample size of the study was small (n=5) and other limitations included a small number of previous studies done on the fathers of children on the autistic spectrum. The literature that is available that focused on the fathers of ASD children are often old and might possibly be out dated. However, this study aimed to hear the voices of the fathers of children on the autistic spectrum and explore how they cope with the daily stressors. Therefore, this study will contribute to the literature on the fathers of ASD children.
- Full Text:
- Date Issued: 2014
- Authors: Hitge, Marcel
- Date: 2014
- Subjects: Autistic children , Parents of autistic children
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/8628 , vital:26414
- Description: In general there is very little research on the coping styles that the fathers of children suffering from Autistic Spectrum Disorder (ASD) use in order to cope with the day-to-day demands and stressors that result from their child‘s unique condition. The research study focuses on the fathers of children on the autistic spectrum and how they cope with the stressors resulting from their children‘s condition on daily basis. The study made use of Bronfenbrenner‘s Ecosystemic Theory of Human Development as the guiding theoretical framework in exploring and describing this specific research domain. This was a qualitative study and it was phenomenological, descriptive and analytical in nature. The reason for this was to hear the voices of the fathers and explore in-depth how they deal with the daily stressors resulting from their children‘s condition. Semi-structured interviews were utilised where the fathers were asked to respond to an open-ended question. The data that was obtained from the fathers was analysed by means of content analysis. The sample size of the study was small (n=5) and other limitations included a small number of previous studies done on the fathers of children on the autistic spectrum. The literature that is available that focused on the fathers of ASD children are often old and might possibly be out dated. However, this study aimed to hear the voices of the fathers of children on the autistic spectrum and explore how they cope with the daily stressors. Therefore, this study will contribute to the literature on the fathers of ASD children.
- Full Text:
- Date Issued: 2014
Fatty acid profiles reveal temporal and spatial differentiation in diets within and among syntopic rocky shore suspension-feeders
- Vermeulen, I, Richoux, N.B, Froneman, Pierre William
- Authors: Vermeulen, I , Richoux, N.B , Froneman, Pierre William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124269 , vital:35582 , http://dx.doi.10.3354/meps10581
- Description: Regional and temporal variations in the diets of rocky shore suspension-feeders (the volcano barnacle Tetraclita serrata, the brown mussel Perna perna and the reef-building poly- chaete Gunnarea gaimardi) were assessed using fatty acid profiling. Specimens were collected up-current and down-current of a river mouth in 2 coastal regions ~50 km apart along southeast- ern South Africa during March and July of 2009. One of the rivers represents a marine-dominated system, and the other a freshwater-dominated system. Our aims were to assess any dietary differences among the 3 suspension-feeders, spatial changes in diet within each species (at regional and local scales—50 and 15 km, respectively), and temporal changes in diet within each species. Fatty acid profiles clearly distinguished the species, with barnacles characterised by dinoflagellate and zooplankton-associated fatty acids; polychaetes, by diatom-associated fatty acids; and mussels, by a combination of mixed phytoplankton and mollusc-specific fatty acids (non-methylene interrupted). These interspecific differences probably arose in part from the contrasting feeding mechanisms employed. The distinctions in diet contribute to ecological partitioning of the sus- pended food within a highly competitive habitat. Regional- and local-scale intraspecific differences in diets were minimal to absent, but temporal distinctions in intraspecific diets were dominant features in the data set, confirming that the trophic environment for suspension-feeders can change markedly throughout a year.
- Full Text: false
- Date Issued: 2014
- Authors: Vermeulen, I , Richoux, N.B , Froneman, Pierre William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124269 , vital:35582 , http://dx.doi.10.3354/meps10581
- Description: Regional and temporal variations in the diets of rocky shore suspension-feeders (the volcano barnacle Tetraclita serrata, the brown mussel Perna perna and the reef-building poly- chaete Gunnarea gaimardi) were assessed using fatty acid profiling. Specimens were collected up-current and down-current of a river mouth in 2 coastal regions ~50 km apart along southeast- ern South Africa during March and July of 2009. One of the rivers represents a marine-dominated system, and the other a freshwater-dominated system. Our aims were to assess any dietary differences among the 3 suspension-feeders, spatial changes in diet within each species (at regional and local scales—50 and 15 km, respectively), and temporal changes in diet within each species. Fatty acid profiles clearly distinguished the species, with barnacles characterised by dinoflagellate and zooplankton-associated fatty acids; polychaetes, by diatom-associated fatty acids; and mussels, by a combination of mixed phytoplankton and mollusc-specific fatty acids (non-methylene interrupted). These interspecific differences probably arose in part from the contrasting feeding mechanisms employed. The distinctions in diet contribute to ecological partitioning of the sus- pended food within a highly competitive habitat. Regional- and local-scale intraspecific differences in diets were minimal to absent, but temporal distinctions in intraspecific diets were dominant features in the data set, confirming that the trophic environment for suspension-feeders can change markedly throughout a year.
- Full Text: false
- Date Issued: 2014
Fatty acid profiles reveal temporal and spatial differentiation in diets within and among syntopic rocky shore suspension-feeders:
- Richoux, Nicole B, Vermeulen, Ilke, Froneman, P William
- Authors: Richoux, Nicole B , Vermeulen, Ilke , Froneman, P William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143346 , vital:38238 , doi: 10.3354/meps10581
- Description: Regional and temporal variations in the diets of rocky shore suspension-feeders (the volcano barnacle Tetraclita serrata, the brown mussel Perna perna and the reef-building polychaete Gunnarea gaimardi) were assessed using fatty acid profiling. Specimens were collected up-current and down-current of a river mouth in 2 coastal regions ~50 km apart along southeastern South Africa during March and July of 2009. One of the rivers represents a marine-dominated system, and the other a freshwater-dominated system. Our aims were to assess any dietary differences among the 3 suspension-feeders, spatial changes in diet within each species (at regional and local scales—50 and 15 km, respectively), and temporal changes in diet within each species.
- Full Text:
- Date Issued: 2014
- Authors: Richoux, Nicole B , Vermeulen, Ilke , Froneman, P William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143346 , vital:38238 , doi: 10.3354/meps10581
- Description: Regional and temporal variations in the diets of rocky shore suspension-feeders (the volcano barnacle Tetraclita serrata, the brown mussel Perna perna and the reef-building polychaete Gunnarea gaimardi) were assessed using fatty acid profiling. Specimens were collected up-current and down-current of a river mouth in 2 coastal regions ~50 km apart along southeastern South Africa during March and July of 2009. One of the rivers represents a marine-dominated system, and the other a freshwater-dominated system. Our aims were to assess any dietary differences among the 3 suspension-feeders, spatial changes in diet within each species (at regional and local scales—50 and 15 km, respectively), and temporal changes in diet within each species.
- Full Text:
- Date Issued: 2014
Financial literacy and behaviour among the black community in Nelson Mandela Bay
- Authors: Antoni, Xolile Lucas
- Date: 2014
- Subjects: Finance, Personal , Investments -- Psychological aspects , Investments -- Decision making
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:9315 , http://hdl.handle.net/10948/d1020027
- Description: South Africa has a poor savings culture. This means that South Africans do not save enough income for a later stage resulting in a relative large number of South African consumers living in debt and using more credit than what they have saved. Almost half of the South African consumers were in debt during the year 2010 and had a negative credit record. Thus consumers in South Africa are not living only in poor conditions but are also open to exploitation by the informal economy. Lenders in the informal economy are known as ‘loan sharks’ because they charge consumers interest rates of between 40 and 60 percent. This is because low income consumers have less access to savings products and credit facilities from the formal economy. These factors are more prevalent among the black consumers, as they use informal credit providers. The sources of credit for black consumers in the informal market are social networks such as friends and family. Furthermore, black consumers have low levels of knowledge regarding issues such as bad debts. Black consumers are also more likely to experience financial problems than other racial groups. This means that black consumers may need to improve their levels of financial knowledge, financial skills and adopt positive financial attitudes to manage their financial problems without obtaining more debt. Thus, financial education may be the way of ensuring that black consumers improve their financial decision-making ability and their financial behaviour. Therefore, the purpose of this study is to investigate the relationships between financial literacy, financial inclusion and financial behaviour among the black community in Nelson Mandela Bay. To achieve the purpose of this study, a literature review was conducted on financial literacy, financial education, financial inclusion and financial behaviour. This was followed by an empirical investigation to establish the relationships between financial literacy, financial inclusion and financial behaviour. In this study, a quantitative research approach was adopted as necessitated by the purpose of this study and also to be able to collect a vast amount of perceptions from the black community. The sample of this study consisted of low to middle income black consumers living in Nelson Mandela Bay.
- Full Text:
- Date Issued: 2014
- Authors: Antoni, Xolile Lucas
- Date: 2014
- Subjects: Finance, Personal , Investments -- Psychological aspects , Investments -- Decision making
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:9315 , http://hdl.handle.net/10948/d1020027
- Description: South Africa has a poor savings culture. This means that South Africans do not save enough income for a later stage resulting in a relative large number of South African consumers living in debt and using more credit than what they have saved. Almost half of the South African consumers were in debt during the year 2010 and had a negative credit record. Thus consumers in South Africa are not living only in poor conditions but are also open to exploitation by the informal economy. Lenders in the informal economy are known as ‘loan sharks’ because they charge consumers interest rates of between 40 and 60 percent. This is because low income consumers have less access to savings products and credit facilities from the formal economy. These factors are more prevalent among the black consumers, as they use informal credit providers. The sources of credit for black consumers in the informal market are social networks such as friends and family. Furthermore, black consumers have low levels of knowledge regarding issues such as bad debts. Black consumers are also more likely to experience financial problems than other racial groups. This means that black consumers may need to improve their levels of financial knowledge, financial skills and adopt positive financial attitudes to manage their financial problems without obtaining more debt. Thus, financial education may be the way of ensuring that black consumers improve their financial decision-making ability and their financial behaviour. Therefore, the purpose of this study is to investigate the relationships between financial literacy, financial inclusion and financial behaviour among the black community in Nelson Mandela Bay. To achieve the purpose of this study, a literature review was conducted on financial literacy, financial education, financial inclusion and financial behaviour. This was followed by an empirical investigation to establish the relationships between financial literacy, financial inclusion and financial behaviour. In this study, a quantitative research approach was adopted as necessitated by the purpose of this study and also to be able to collect a vast amount of perceptions from the black community. The sample of this study consisted of low to middle income black consumers living in Nelson Mandela Bay.
- Full Text:
- Date Issued: 2014
First Vice chancelor`s excellent awards` ceremony
- Jonas, Nombulelo, Scheckle, Linda, Toni, Noluthando
- Authors: Jonas, Nombulelo , Scheckle, Linda , Toni, Noluthando
- Date: 2014
- Language: English
- Type: Newsletter
- Identifier: vital:12227 , http://hdl.handle.net/10353/d1016145
- Description: UFH Teaching and Learning centre news letter 2014
- Full Text:
- Date Issued: 2014
- Authors: Jonas, Nombulelo , Scheckle, Linda , Toni, Noluthando
- Date: 2014
- Language: English
- Type: Newsletter
- Identifier: vital:12227 , http://hdl.handle.net/10353/d1016145
- Description: UFH Teaching and Learning centre news letter 2014
- Full Text:
- Date Issued: 2014
Fishing for resilience : herbivore and algal dynamics on coral reefs in Kenya.
- Authors: Humphries, Austin Turner
- Date: 2014
- Subjects: Coral reef conservation -- Kenya , Coral reef ecology -- Kenya , Coral reef biology -- Kenya , Coral reef fishes -- Kenya , Herbivores -- Kenya , Algae -- Control -- Kenya , Fishery management -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5877 , http://hdl.handle.net/10962/d1013147
- Description: Herbivory is a key process that mediates the abundance of primary producers and community composition in both terrestrial and aquatic ecosystems. On tropical coral reefs, changes in herbivory are often related to phase shifts between coral-dominance and dominance by seaweeds, or foliose macroalgae. Resilience or capacity to resist and reverse such phase shifts is, therefore, viewed as a critical function on coral reefs. This thesis used grazer exclusion and assay experiments at six sites within three different fisheries management regimes in Kenya to identify the impacts of herbivores (sea urchins and fishes) on algal dynamics in the context of coral reef resilience. First, I examined the grazing rates necessary to prevent phase shifts by quantifying consumption and algal production. Here, I found that, over a 390-day experiment, at least 50 percent of algal production must be consumed to avoid accumulation of algal biomass. Using video observations, I also showed that scraping parrotfishes remove more algae (per unit of fish biomass) than previously assumed, and that sea urchins, if released from predation, have similar impacts to fishes. Then I focused on algal succession, and found that sea urchins and fishes have different effects that are mediated by their abundances and species composition. Where sea urchins were less abundant and parrotfishes absent (e.g. young fisheries closures), progression of algae from turfs to early and then late successional macroalgae occurred rapidly and within 100 days. I then turned my focus to the removal of already established macroalgae (grown for > 1 yr in the absence of herbivores) and showed that sea urchins and browsing fishes were able to remove significant amounts of macroalgae where either herbivore was abundant. However, using multiple-choice selectivity assays and in situ video recordings, I found that browsing fishes fed very selectively with low overlap in diet among species, leading to low functional redundancy within a high diversity system. Finally, using long-term survey data (from 28 sites) to build a 43-year chronosequence, I showed that it is possible that the effects of herbivory will not be constant across transitions from open fishing to fishery closures through non-linear grazing intensity. Therefore, increases in herbivory within fisheries closures may not be immediate and may allow a window of opportunity for algae to go from turf to unpalatable macroalgae until scraping and browsing fishes fully recover from fishing (~ 20 years). The findings in this thesis are novel and raise concern over the potential implications of the slow recovery of parrotfishes or, given lower than expected functional redundancy in grazing effects, the absence of even one browsing fish species in fisheries closures. Overall, this thesis highlights the importance of herbivore community dynamics in mediating interactions among algae, and provides new insights for conservation and management actions that attempt to bolster the resilience of coral reefs.
- Full Text:
- Date Issued: 2014
- Authors: Humphries, Austin Turner
- Date: 2014
- Subjects: Coral reef conservation -- Kenya , Coral reef ecology -- Kenya , Coral reef biology -- Kenya , Coral reef fishes -- Kenya , Herbivores -- Kenya , Algae -- Control -- Kenya , Fishery management -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5877 , http://hdl.handle.net/10962/d1013147
- Description: Herbivory is a key process that mediates the abundance of primary producers and community composition in both terrestrial and aquatic ecosystems. On tropical coral reefs, changes in herbivory are often related to phase shifts between coral-dominance and dominance by seaweeds, or foliose macroalgae. Resilience or capacity to resist and reverse such phase shifts is, therefore, viewed as a critical function on coral reefs. This thesis used grazer exclusion and assay experiments at six sites within three different fisheries management regimes in Kenya to identify the impacts of herbivores (sea urchins and fishes) on algal dynamics in the context of coral reef resilience. First, I examined the grazing rates necessary to prevent phase shifts by quantifying consumption and algal production. Here, I found that, over a 390-day experiment, at least 50 percent of algal production must be consumed to avoid accumulation of algal biomass. Using video observations, I also showed that scraping parrotfishes remove more algae (per unit of fish biomass) than previously assumed, and that sea urchins, if released from predation, have similar impacts to fishes. Then I focused on algal succession, and found that sea urchins and fishes have different effects that are mediated by their abundances and species composition. Where sea urchins were less abundant and parrotfishes absent (e.g. young fisheries closures), progression of algae from turfs to early and then late successional macroalgae occurred rapidly and within 100 days. I then turned my focus to the removal of already established macroalgae (grown for > 1 yr in the absence of herbivores) and showed that sea urchins and browsing fishes were able to remove significant amounts of macroalgae where either herbivore was abundant. However, using multiple-choice selectivity assays and in situ video recordings, I found that browsing fishes fed very selectively with low overlap in diet among species, leading to low functional redundancy within a high diversity system. Finally, using long-term survey data (from 28 sites) to build a 43-year chronosequence, I showed that it is possible that the effects of herbivory will not be constant across transitions from open fishing to fishery closures through non-linear grazing intensity. Therefore, increases in herbivory within fisheries closures may not be immediate and may allow a window of opportunity for algae to go from turf to unpalatable macroalgae until scraping and browsing fishes fully recover from fishing (~ 20 years). The findings in this thesis are novel and raise concern over the potential implications of the slow recovery of parrotfishes or, given lower than expected functional redundancy in grazing effects, the absence of even one browsing fish species in fisheries closures. Overall, this thesis highlights the importance of herbivore community dynamics in mediating interactions among algae, and provides new insights for conservation and management actions that attempt to bolster the resilience of coral reefs.
- Full Text:
- Date Issued: 2014
Food security in a perfect storm: using the ecosystem services framework to increase understanding
- Poppy, G M, Chiotha, S, Eigenbrod, Felix, Harvey, C A, Honzák, M, Hudson, M D, Jarvis, A, Madise, N J, Schreckenberg, Kate, Shackleton, Charlie M, Villa, F, Dawson, T P
- Authors: Poppy, G M , Chiotha, S , Eigenbrod, Felix , Harvey, C A , Honzák, M , Hudson, M D , Jarvis, A , Madise, N J , Schreckenberg, Kate , Shackleton, Charlie M , Villa, F , Dawson, T P
- Date: 2014
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60952 , vital:27900 , http://dx.doi.org/10.1098/rstb.2012.0288
- Description: Achieving food security in a ‘perfect storm’ scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.
- Full Text:
- Date Issued: 2014
- Authors: Poppy, G M , Chiotha, S , Eigenbrod, Felix , Harvey, C A , Honzák, M , Hudson, M D , Jarvis, A , Madise, N J , Schreckenberg, Kate , Shackleton, Charlie M , Villa, F , Dawson, T P
- Date: 2014
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60952 , vital:27900 , http://dx.doi.org/10.1098/rstb.2012.0288
- Description: Achieving food security in a ‘perfect storm’ scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.
- Full Text:
- Date Issued: 2014
Formalisation, informalisation and the labour process within the minibus taxi industry in East London, South Africa
- Fobosi, Siyabulela Christopher
- Authors: Fobosi, Siyabulela Christopher
- Date: 2014
- Subjects: Taxicab industry -- South Africa -- East London , Taxicab industry -- South Africa -- East London -- Personnel management , Informal sector (Economics) -- South Africa -- East London , Economics -- Sociological aspects , Industrial relations -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3367 , http://hdl.handle.net/10962/d1012076 , Taxicab industry -- South Africa -- East London , Taxicab industry -- South Africa -- East London -- Personnel management , Informal sector (Economics) -- South Africa -- East London , Economics -- Sociological aspects , Industrial relations -- South Africa -- East London
- Description: This thesis focuses on the labour process within the minibus taxi industry in East London, South Africa. This industry is structurally situated within the informal sector or economy but is marked by contradictory processes of formalisation and in-formalisation. Though the taxi industry seems to straddle the formal and informal economies in South Africa, the study is conceptually framed in terms of the informal sector but in a critically-engaged fashion. The very distinction between formal and informal economies, whether in South Africa or elsewhere, is open to dispute; and, even if accepted, there are differing conceptualisations of the relationship between the ‘two’ economies. Also, the conceptual clarity of the term ‘informal economy’ has been subject to scrutiny, given the vast range of activities it is said to incorporate. While the distinction between formal and informal economies may be a useful conceptual starting-point, this thesis demonstrates that it is analytically useful to speak of degrees and forms of formalisation and in-formalisation along a continuum, rather than to dichotomize economies. The thesis therefore analyses in depth the competing and tension-riddled processes of formalisation and in-formalisation in the minibus taxi industry, and with a specific focus on the labour process.
- Full Text:
- Date Issued: 2014
- Authors: Fobosi, Siyabulela Christopher
- Date: 2014
- Subjects: Taxicab industry -- South Africa -- East London , Taxicab industry -- South Africa -- East London -- Personnel management , Informal sector (Economics) -- South Africa -- East London , Economics -- Sociological aspects , Industrial relations -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3367 , http://hdl.handle.net/10962/d1012076 , Taxicab industry -- South Africa -- East London , Taxicab industry -- South Africa -- East London -- Personnel management , Informal sector (Economics) -- South Africa -- East London , Economics -- Sociological aspects , Industrial relations -- South Africa -- East London
- Description: This thesis focuses on the labour process within the minibus taxi industry in East London, South Africa. This industry is structurally situated within the informal sector or economy but is marked by contradictory processes of formalisation and in-formalisation. Though the taxi industry seems to straddle the formal and informal economies in South Africa, the study is conceptually framed in terms of the informal sector but in a critically-engaged fashion. The very distinction between formal and informal economies, whether in South Africa or elsewhere, is open to dispute; and, even if accepted, there are differing conceptualisations of the relationship between the ‘two’ economies. Also, the conceptual clarity of the term ‘informal economy’ has been subject to scrutiny, given the vast range of activities it is said to incorporate. While the distinction between formal and informal economies may be a useful conceptual starting-point, this thesis demonstrates that it is analytically useful to speak of degrees and forms of formalisation and in-formalisation along a continuum, rather than to dichotomize economies. The thesis therefore analyses in depth the competing and tension-riddled processes of formalisation and in-formalisation in the minibus taxi industry, and with a specific focus on the labour process.
- Full Text:
- Date Issued: 2014
Formulation, development and assessment of efavirenz-loaded lipid nanocarriers
- Authors: Makoni, Pedzisai Anotida
- Date: 2014
- Subjects: Nanomedicine , Drug delivery systems , Antiretroviral agents Psychotropic effects , AIDS dementia complex
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/209981 , vital:47448
- Description: The feasibility of incorporating efavirenz (EFV) into innovative solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) using the hot high-pressure homogenization (HHPH) technique was investigated in an attempt to address the shortcomings in therapy associated with the use of conventional dosage forms. The shortcomings include the unpalatable taste of API in solution, instability in the presence of light when in solution and psychiatric side effects of the API. In particular, sustained release approaches may reduce or limit the incidence of adverse psychiatric effects of EFV and alleviate Acquired Immune Deficiency Syndrome (AIDS)-related complications such as AIDS Dementia Complex (ADC) in patients, ultimately improving their quality of life. Prior to initiating pre-formulation, formulation development and optimization studies of EFV-loaded SLN and/or NLC, Response Surface Methodology (RSM) in conjunction with central composite design (CCD), was used to develop and validate suitable methods for the quantitative determination of EFV in pharmaceutical formulations and for monitoring EFV release from SLN and/or NLC in vitro. Simple, accurate, precise, sensitive and stabilityindicating reversed phase-high performance liquid chromatography (RP-HPLC) methods with UV and electrochemical (EC) detection were developed, validated and optimized for in vitro analysis of EFV in formulations. On the basis of risk-to-benefit ratio the RP-HPLC method with UV detection was selected as the most suitable for the quantitative determination of EFV in pharmaceutical formulations, and was applied to in vitro release studies of EFV from SLN and/or NLC. Pre-formulation studies were undertaken to investigate the thermal stability of EFV so as to facilitate the selection of lipid excipients for the manufacture of nanocarriers, and to establish their compatibility with EFV. It was found that EFV was thermostable up to a temperature of approximately 200°C, indicating that HHPH could be used for the manufacture of EFV-loaded SLN and/or NLC. Lipid screening revealed that EFV is highly soluble in solid and liquid lipids, with glyceryl monostearate and Transcutol® HP showing the best solubilizing potential for EFV. Glyceryl monostearate exists in a stable β-modification prior to exposure to heat, but exists in the α-polymorphic modification following exposure to heat. It was established that the addition of Transcutol® HP to glyceryl monostearate revealed the co-existence of the α- and β’-polymorphic modifications, thereby revealing the existence of the modifications in NLC produced from the optimum lipid combination. Furthermore, an investigation of binary mixtures of EFV/glyceryl monostearate and glyceryl monostearate/Transcutol® HP, in addition to eutectic mixtures of EFV, glyceryl monostearate and Transcutol® HP, revealed no interaction between EFV and the lipids selected for the production of the nanocarriers. Due to the significantly higher solubility of EFV in Transcutol® HP than in to glyceryl monostearate, NLC are most likely to have a higher LC and EE than SLN. In addition, the existence of both the α- and β’-polymorphic modifications in the binary mixture of the lipid implies that EFV expulsion on prolonged storage is unlikely to occur from NLC when compared to SLN. Consequently formulation development and optimization studies of SLN and NLC were performed to investigate the potential to deliver EFV from a novel technology with an appropriate LC and EE for EFV. Tween®80 was selected for use in these formulations as the use of this surfactant facilitates the targeting of nanocarriers to the CNS. RSM in conjunction with a Box-Behnken Design (BBD) was used to establish the effects of process variables, such as number of homogenization cycles and pressure, in addition to formulation variables such as amount of EFV and Tween®80 on the particle size (PS), polydispersity index (PDI), zeta potential (ZP), visual assessment (VA) and release rate (RR) of EFV after 24 hours. In addition the LC and EE, degree of crystallinity and lipid modification, shape and surface morphology of the optimized batches were investigated to ensure that EFV-loaded SLN and NLC of desirable quality were produced. On the day of manufacture the mean PS and PDI of EFV-loaded SLN was 59.00 ± 23.16 nm and 0.382 ± 0.054 respectively. The mean PS and PDI of EFV-loaded NLC was 34.73 ± 0.7709 nm and 0.394 ± 0.027 respectively. The formulations were in the nanometer range and exhibited a narrow particle size distribution, as indicated by the PDI values. The ZP values for optimized SLN and NLC generated on the day of manufacture using HPLC grade water as the dispersion medium were -32.5 ± 4.99 mV and -22.4 ± 3.72 mV respectively. In addition the optimized batches of SLN and NLC revealed a decrease in crystallinity in comparison to bulk lipid material. DSC, WAXS and FT-IR revealed that EFV was molecularly dispersed in the nanocarriers. In addition EFV-loaded SLN existed in a single α-polymorphic form, whereas EFV-loaded NLC exhibited the co-existence of α- and β’-polymorphic forms. Generally SLN and NLC were spherically shaped when viewed under transmission electron microscopy (TEM) and scanning electron microscopy (SEM). On the day of manufacture the EE and LC of EFVloaded SLN was found to be 96.77 ± 0.453 % and 9.68 ± 1.772 % respectively. The EE and LC of EFV-loaded NLC was 99.93 ± 0.413 and 9.995 ± 0.672 respectively. The release profiles for the optimized formulations of SLN and NLC exhibited an initial burst release over the first 0-3 hours of testing, after which the release was sustained for up to 24 hours. The cumulative % EFV released over 24 hours was higher from SLN (91.5±3.423 %) than that observed for NLC (73.6±4.34 %). Stability studies performed for 8 weeks on the optimized batches of the SLN and the NLC were also conducted so as to ensure product quality. The formulations were assessed in terms of parameters considered benchmarks of stability, and included ZP, PS, PDI, LC and EE. Generally these parameters remained unchanged following storage for 8 weeks at 25°C/60% RH but showed considerable changes following storage for 8 weeks at 40°C/75% RH. These studies reveal that SLN and NLC when stored at 25°C/60% RH have the potential to be used as colloidal delivery systems for EFV that have the potential to protect EFV from photodegradation and sustain release into brain tissue. The latter will ultimately reduce or limit the incidence of adverse psychiatric effects and potentially alleviate AIDS-related complications such as ADC in patients with HIV/AIDS, ultimately improving their quality of life. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2014
- Full Text:
- Date Issued: 2014
- Authors: Makoni, Pedzisai Anotida
- Date: 2014
- Subjects: Nanomedicine , Drug delivery systems , Antiretroviral agents Psychotropic effects , AIDS dementia complex
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/209981 , vital:47448
- Description: The feasibility of incorporating efavirenz (EFV) into innovative solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) using the hot high-pressure homogenization (HHPH) technique was investigated in an attempt to address the shortcomings in therapy associated with the use of conventional dosage forms. The shortcomings include the unpalatable taste of API in solution, instability in the presence of light when in solution and psychiatric side effects of the API. In particular, sustained release approaches may reduce or limit the incidence of adverse psychiatric effects of EFV and alleviate Acquired Immune Deficiency Syndrome (AIDS)-related complications such as AIDS Dementia Complex (ADC) in patients, ultimately improving their quality of life. Prior to initiating pre-formulation, formulation development and optimization studies of EFV-loaded SLN and/or NLC, Response Surface Methodology (RSM) in conjunction with central composite design (CCD), was used to develop and validate suitable methods for the quantitative determination of EFV in pharmaceutical formulations and for monitoring EFV release from SLN and/or NLC in vitro. Simple, accurate, precise, sensitive and stabilityindicating reversed phase-high performance liquid chromatography (RP-HPLC) methods with UV and electrochemical (EC) detection were developed, validated and optimized for in vitro analysis of EFV in formulations. On the basis of risk-to-benefit ratio the RP-HPLC method with UV detection was selected as the most suitable for the quantitative determination of EFV in pharmaceutical formulations, and was applied to in vitro release studies of EFV from SLN and/or NLC. Pre-formulation studies were undertaken to investigate the thermal stability of EFV so as to facilitate the selection of lipid excipients for the manufacture of nanocarriers, and to establish their compatibility with EFV. It was found that EFV was thermostable up to a temperature of approximately 200°C, indicating that HHPH could be used for the manufacture of EFV-loaded SLN and/or NLC. Lipid screening revealed that EFV is highly soluble in solid and liquid lipids, with glyceryl monostearate and Transcutol® HP showing the best solubilizing potential for EFV. Glyceryl monostearate exists in a stable β-modification prior to exposure to heat, but exists in the α-polymorphic modification following exposure to heat. It was established that the addition of Transcutol® HP to glyceryl monostearate revealed the co-existence of the α- and β’-polymorphic modifications, thereby revealing the existence of the modifications in NLC produced from the optimum lipid combination. Furthermore, an investigation of binary mixtures of EFV/glyceryl monostearate and glyceryl monostearate/Transcutol® HP, in addition to eutectic mixtures of EFV, glyceryl monostearate and Transcutol® HP, revealed no interaction between EFV and the lipids selected for the production of the nanocarriers. Due to the significantly higher solubility of EFV in Transcutol® HP than in to glyceryl monostearate, NLC are most likely to have a higher LC and EE than SLN. In addition, the existence of both the α- and β’-polymorphic modifications in the binary mixture of the lipid implies that EFV expulsion on prolonged storage is unlikely to occur from NLC when compared to SLN. Consequently formulation development and optimization studies of SLN and NLC were performed to investigate the potential to deliver EFV from a novel technology with an appropriate LC and EE for EFV. Tween®80 was selected for use in these formulations as the use of this surfactant facilitates the targeting of nanocarriers to the CNS. RSM in conjunction with a Box-Behnken Design (BBD) was used to establish the effects of process variables, such as number of homogenization cycles and pressure, in addition to formulation variables such as amount of EFV and Tween®80 on the particle size (PS), polydispersity index (PDI), zeta potential (ZP), visual assessment (VA) and release rate (RR) of EFV after 24 hours. In addition the LC and EE, degree of crystallinity and lipid modification, shape and surface morphology of the optimized batches were investigated to ensure that EFV-loaded SLN and NLC of desirable quality were produced. On the day of manufacture the mean PS and PDI of EFV-loaded SLN was 59.00 ± 23.16 nm and 0.382 ± 0.054 respectively. The mean PS and PDI of EFV-loaded NLC was 34.73 ± 0.7709 nm and 0.394 ± 0.027 respectively. The formulations were in the nanometer range and exhibited a narrow particle size distribution, as indicated by the PDI values. The ZP values for optimized SLN and NLC generated on the day of manufacture using HPLC grade water as the dispersion medium were -32.5 ± 4.99 mV and -22.4 ± 3.72 mV respectively. In addition the optimized batches of SLN and NLC revealed a decrease in crystallinity in comparison to bulk lipid material. DSC, WAXS and FT-IR revealed that EFV was molecularly dispersed in the nanocarriers. In addition EFV-loaded SLN existed in a single α-polymorphic form, whereas EFV-loaded NLC exhibited the co-existence of α- and β’-polymorphic forms. Generally SLN and NLC were spherically shaped when viewed under transmission electron microscopy (TEM) and scanning electron microscopy (SEM). On the day of manufacture the EE and LC of EFVloaded SLN was found to be 96.77 ± 0.453 % and 9.68 ± 1.772 % respectively. The EE and LC of EFV-loaded NLC was 99.93 ± 0.413 and 9.995 ± 0.672 respectively. The release profiles for the optimized formulations of SLN and NLC exhibited an initial burst release over the first 0-3 hours of testing, after which the release was sustained for up to 24 hours. The cumulative % EFV released over 24 hours was higher from SLN (91.5±3.423 %) than that observed for NLC (73.6±4.34 %). Stability studies performed for 8 weeks on the optimized batches of the SLN and the NLC were also conducted so as to ensure product quality. The formulations were assessed in terms of parameters considered benchmarks of stability, and included ZP, PS, PDI, LC and EE. Generally these parameters remained unchanged following storage for 8 weeks at 25°C/60% RH but showed considerable changes following storage for 8 weeks at 40°C/75% RH. These studies reveal that SLN and NLC when stored at 25°C/60% RH have the potential to be used as colloidal delivery systems for EFV that have the potential to protect EFV from photodegradation and sustain release into brain tissue. The latter will ultimately reduce or limit the incidence of adverse psychiatric effects and potentially alleviate AIDS-related complications such as ADC in patients with HIV/AIDS, ultimately improving their quality of life. , Thesis (MSc) -- Faculty of Pharmacy, Pharmacy, 2014
- Full Text:
- Date Issued: 2014
Foundation Phase teachers’ responses to curriculum change in South Africa over the past two decades: a case study of two schools
- Authors: Nakaonga, Ruth
- Date: 2014
- Subjects: Curriculum change -- South Africa , Educational change -- South Africa , Education, Primary -- South Africa , Teachers -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2002 , http://hdl.handle.net/10962/d1015648
- Description: South Africa has experienced three significant curriculum reforms since 1994. The first of these replaced the ‘apartheid’ curriculum with C2005 based largely on Outcomes Based Education. In the second stage C2005 gave way to the National Curriculum Statements, a simplified version of C2005. Finally, the NCS was replaced with CAPS. This research study investigates the perceptions, attitudes and experiences of teachers implementing these curriculum changes. It focuses in particular on Foundation Phase in 2012, the year in which CAPS was implemented in that phase. It took the form of an interpretive case study, using qualitative data generating and analysis techniques. Principals and selected teachers of two primary schools in Grahamstown – an ex-Model C school and a performing ‘township’ school - were the respondents of the study. Data were generated chiefly through questionnaires and semi-structured interviews, supplemented by document analysis and observation. The findings revealed that the teachers in this study are frustrated and angry about the frequency of curriculum change in South Africa. Respondents are particularly critical of OBE and the NCS. While they welcome the need for a departure from ‘apartheid’ curricula, they feel the pedagogical underpinning of the NCS – with its emphasis on learner-centredness – disempowered them as teachers. Hence, they welcomed CAPS which seems to return to content – rather than skills and attitudes – and re-instates the teacher as the chief giver of knowledge and manager of learning.
- Full Text:
- Date Issued: 2014
- Authors: Nakaonga, Ruth
- Date: 2014
- Subjects: Curriculum change -- South Africa , Educational change -- South Africa , Education, Primary -- South Africa , Teachers -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2002 , http://hdl.handle.net/10962/d1015648
- Description: South Africa has experienced three significant curriculum reforms since 1994. The first of these replaced the ‘apartheid’ curriculum with C2005 based largely on Outcomes Based Education. In the second stage C2005 gave way to the National Curriculum Statements, a simplified version of C2005. Finally, the NCS was replaced with CAPS. This research study investigates the perceptions, attitudes and experiences of teachers implementing these curriculum changes. It focuses in particular on Foundation Phase in 2012, the year in which CAPS was implemented in that phase. It took the form of an interpretive case study, using qualitative data generating and analysis techniques. Principals and selected teachers of two primary schools in Grahamstown – an ex-Model C school and a performing ‘township’ school - were the respondents of the study. Data were generated chiefly through questionnaires and semi-structured interviews, supplemented by document analysis and observation. The findings revealed that the teachers in this study are frustrated and angry about the frequency of curriculum change in South Africa. Respondents are particularly critical of OBE and the NCS. While they welcome the need for a departure from ‘apartheid’ curricula, they feel the pedagogical underpinning of the NCS – with its emphasis on learner-centredness – disempowered them as teachers. Hence, they welcomed CAPS which seems to return to content – rather than skills and attitudes – and re-instates the teacher as the chief giver of knowledge and manager of learning.
- Full Text:
- Date Issued: 2014
Frontiers of exclusion and enclusion: post-apartheid suburban social dynamics in East London, Beacon Bay
- Authors: Buku, Luzuko
- Date: 2014
- Subjects: Apartheid -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc
- Identifier: http://hdl.handle.net/10353/1316 , vital:26545
- Description: This dissertation deals with the nature of the black middle-class assimilation in the South African suburban space, a space that was the sole preserve of the white middle-class during apartheid. It explores the relationship between these races as they come to meet in this space and what new identities are being formed. It also explores the relationship between both the black and white suburbanites and the urban poor who stay in an adjacent area to the suburb. The study uses the Beacon Bay area, which is constituted by one of East London’s most affluent suburbs and a poor township, Nompumelelo, to show how the emergent black middle-class has managed to enter this space in the post-apartheid era. Previous studies by Richard Ballard (2004) and Grant Saff (2001) have shown how the white middle-class has always been against any form of race or class mixing. Within the suburb, the new black suburbanites in Beacon Bay appear to have been welcomed but with conditions by their fellow white counterparts. The relationship between these two races does not stretch beyond meet and greets and it is only in the second generation black middle-class that you find better and non-superficial relations with fellow white suburbanites. In the older generation, the generation that experienced apartheid, the relationship between these two races has been that of tolerance and serious escape of contact unless when necessary. The children of both white and black families, though, have a far better relationship in school and in sport than their parents. This has created another area of contact for both these races and it bears potential for meaningful integration in the suburban space. Externally as it relates to relations between the black middle-class and the urban poor, the findings show that these new black suburbanites express a similar discomfort as the white suburbanites about the urban poor’s presence in the area. This shows that the evolution of the Beacon Bay suburb, with its deep-rooted discourse of white middle-class exclusivity, has not been entirely about hatred of the urban poor necessarily but about an identity ascription of what it means to live in a suburb. Despite these realities traditional ceremonies organised by the black middle-class in the suburbs and the church appear to be playing a role in creating relations between these suburbanites and the Nompumelelo residents. This is why we have decided to use the conceptualisation of the 18th century frontier zone as the borders of segregation within the suburb and between the suburban residents and those of the township can be crossed and re-crossed.
- Full Text:
- Date Issued: 2014
- Authors: Buku, Luzuko
- Date: 2014
- Subjects: Apartheid -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc
- Identifier: http://hdl.handle.net/10353/1316 , vital:26545
- Description: This dissertation deals with the nature of the black middle-class assimilation in the South African suburban space, a space that was the sole preserve of the white middle-class during apartheid. It explores the relationship between these races as they come to meet in this space and what new identities are being formed. It also explores the relationship between both the black and white suburbanites and the urban poor who stay in an adjacent area to the suburb. The study uses the Beacon Bay area, which is constituted by one of East London’s most affluent suburbs and a poor township, Nompumelelo, to show how the emergent black middle-class has managed to enter this space in the post-apartheid era. Previous studies by Richard Ballard (2004) and Grant Saff (2001) have shown how the white middle-class has always been against any form of race or class mixing. Within the suburb, the new black suburbanites in Beacon Bay appear to have been welcomed but with conditions by their fellow white counterparts. The relationship between these two races does not stretch beyond meet and greets and it is only in the second generation black middle-class that you find better and non-superficial relations with fellow white suburbanites. In the older generation, the generation that experienced apartheid, the relationship between these two races has been that of tolerance and serious escape of contact unless when necessary. The children of both white and black families, though, have a far better relationship in school and in sport than their parents. This has created another area of contact for both these races and it bears potential for meaningful integration in the suburban space. Externally as it relates to relations between the black middle-class and the urban poor, the findings show that these new black suburbanites express a similar discomfort as the white suburbanites about the urban poor’s presence in the area. This shows that the evolution of the Beacon Bay suburb, with its deep-rooted discourse of white middle-class exclusivity, has not been entirely about hatred of the urban poor necessarily but about an identity ascription of what it means to live in a suburb. Despite these realities traditional ceremonies organised by the black middle-class in the suburbs and the church appear to be playing a role in creating relations between these suburbanites and the Nompumelelo residents. This is why we have decided to use the conceptualisation of the 18th century frontier zone as the borders of segregation within the suburb and between the suburban residents and those of the township can be crossed and re-crossed.
- Full Text:
- Date Issued: 2014
Fundamental movement skill proficiency status of girls aged 9-to-12 years from previously disadvantaged communities in Nelson Mandela Bay
- Authors: Kahts, Samantha Andrea
- Date: 2014
- Subjects: Movement therapy for children -- South Africa -- Port Elizabeth , Exercise therapy -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10107 , http://ndl.handle.net/10948/d1020060
- Description: A lack of fundamental movement skill (FMS) proficiency in children can contribute to decreased physical activity (PA) levels, increased adiposity and poor acquisition of specialised sport specific movement skills. To prevent the latter, the identification of FMS status in early and middle childhood years is needed for targeted and specific interventions. Against the backdrop of physical education being omitted from the South African school curriculum, the presence of a patriarchal society, gender sporting stereotyping, high levels of unemployment and low education levels; the assessment of FMS status is particularly warranted. Aim of Study: The primary aim of this study was to assess the FMS proficiency of girls aged 9-to-12 years from previously disadvantaged communities within Nelson Mandela Bay. Methodology:A descriptive-exploratory-contextual study design, employing quantitative assessment techniques, was utilized. The sample comprised of 227 girls. Convenience sampling was employed. Testing consisted of FMS proficiency tests in the 20m and 40m sprint, standing long jump, throwing for distance, catching, static balance and throwing for accuracy. FMS process scores were assessed with the body component (BC) and Test of Gross Motor Development II (TGMD II) approaches. Anthropometric measurements of the standing and seated height, mass, arm span and leg length were additionally measured. Microsoft Excel® and Statistica® were used for descriptive and inferential statistical analysis. In the case of significant ANOVA results, the Scheffe post hoc test was used for pairwise comparisons. Statistical significance was set at p<.05 and practical significance (Cohen’s d) was set at d>.2. Pearson Correlation Coefficient identified statistical and practical correlations between two variables and chi square was applied to indicate differences in frequency distribution tables. Cramer’s V values were applied to determine practical significance in the case where statistical significant differences were identified between sets of frequency distributions.
- Full Text:
- Date Issued: 2014
- Authors: Kahts, Samantha Andrea
- Date: 2014
- Subjects: Movement therapy for children -- South Africa -- Port Elizabeth , Exercise therapy -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10107 , http://ndl.handle.net/10948/d1020060
- Description: A lack of fundamental movement skill (FMS) proficiency in children can contribute to decreased physical activity (PA) levels, increased adiposity and poor acquisition of specialised sport specific movement skills. To prevent the latter, the identification of FMS status in early and middle childhood years is needed for targeted and specific interventions. Against the backdrop of physical education being omitted from the South African school curriculum, the presence of a patriarchal society, gender sporting stereotyping, high levels of unemployment and low education levels; the assessment of FMS status is particularly warranted. Aim of Study: The primary aim of this study was to assess the FMS proficiency of girls aged 9-to-12 years from previously disadvantaged communities within Nelson Mandela Bay. Methodology:A descriptive-exploratory-contextual study design, employing quantitative assessment techniques, was utilized. The sample comprised of 227 girls. Convenience sampling was employed. Testing consisted of FMS proficiency tests in the 20m and 40m sprint, standing long jump, throwing for distance, catching, static balance and throwing for accuracy. FMS process scores were assessed with the body component (BC) and Test of Gross Motor Development II (TGMD II) approaches. Anthropometric measurements of the standing and seated height, mass, arm span and leg length were additionally measured. Microsoft Excel® and Statistica® were used for descriptive and inferential statistical analysis. In the case of significant ANOVA results, the Scheffe post hoc test was used for pairwise comparisons. Statistical significance was set at p<.05 and practical significance (Cohen’s d) was set at d>.2. Pearson Correlation Coefficient identified statistical and practical correlations between two variables and chi square was applied to indicate differences in frequency distribution tables. Cramer’s V values were applied to determine practical significance in the case where statistical significant differences were identified between sets of frequency distributions.
- Full Text:
- Date Issued: 2014
Fundamental movement skill proficiency status of girls aged 9-to-12 years from previously disadvantaged communities in Nelson Mandela Bay
- Authors: Kahts, Samantha Andrea
- Date: 2014
- Subjects: Movement therapy for children -- South Africa -- Port Elizabeth , Exercise therapy -- South Africa -- Port Elizabeth , Kinesiology -- Social aspects -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10114 , http://hdl.handle.net/10948/d1021035
- Description: Problem Statement A lack of fundamental movement skill (FMS) proficiency in children can contribute to decreased physical activity (PA) levels, increased adiposity and poor acquisition of specialised sport specific movement skills. To prevent the latter, the identification of FMS status in early and middle childhood years is needed for targeted and specific interventions. Against the backdrop of physical education being omitted from the South African school curriculum, the presence of a patriarchal society, gender sporting stereotyping, high levels of unemployment and low education levels; the assessment of FMS status is particularly warranted. Aim of Study The primary aim of this study was to assess the FMS proficiency of girls aged 9-to-12 years from previously disadvantaged communities within Nelson Mandela Bay. Methodology A descriptive-exploratory-contextual study design, employing quantitative assessment techniques, was utilized. The sample comprised of 227 girls. Convenience sampling was employed. Testing consisted of FMS proficiency tests in the 20m and 40m sprint, standing long jump, throwing for distance, catching, static balance and throwing for accuracy. FMS process scores were assessed with the body component (BC) and Test of Gross Motor Development II (TGMD II) approaches. Anthropometric measurements of the standing and seated height, mass, arm span and leg length were additionally measured. Microsoft Excel® and Statistica® were used for descriptive and inferential statistical analysis. In the case of significant ANOVA results, the Scheffe post hoc test was used for pairwise comparisons. Statistical significance was set at p<.05 and practical significance (Cohen’s d) was set at d>.2. Pearson Correlation Coefficient identified statistical and practical correlations between two variables and chi square was applied to indicate differences in frequency distribution tables. Cramer’s V values were applied to determine practical significance in the case where statistical significant differences were identified between sets of frequency distributions The BC approach indicated that most participants could not proficiently perform the run for speed (94.71 percent), standing long jump (96.9 percent) or throw for distance (83.56 percent). Only the catch was performed proficiently (91.19 percent). TGMD II results for the present study indicated that participants’ run for speed (100 percent) and catch (96.92 percent) were performed proficiently and their standing long jump (93.78 percent) and throw for distance (83.56 percent) process scores were performed least proficiently. Only the catch composite BC scores had a statistically (df=1.31; f=3.24; p=.024) and practically significant (d=0.82) improvement in the BC scores between the age groups 9 and 12 years. Only the standing long jump, throw for distance and throw for accuracy product scores improved statically and practically significantly with aging (p<.05; d>.2). Hence the further participants jumped, the faster they ran. Standing and seated height, weight and arm span improved statistically and practically significantly with age (p<.05; d>.2). All anthropometric variables, except for leg length, had a positive medium correlation (r=.335 to r=.439) with balance errors and this was only in 12 year olds. The throw for distance product scores had a medium correlation to seated height (r=.32) and arm span (r=.33). The run for speed had a medium correlation (r=.313) with mass. According to the IOTF classifications 24.67 percent of children were overweight and 7.49 percent of children were obese. Statistically significant differences were found for the run for speed (df=224; f=27.07; p=2.9E-11) and standing long jump (df=224; f=15.68; p=4.2E-07) when comparing product scores to normal weight, overweight and obese participants. These differences were furthermore found to be of medium to large practical significance between the normal and obese participants for the run for speed (d=0.61 to d=1.77) and Standing Long Jump (d=0.40 to d=1.33). On average 50 percent and 55 percent of participants partook 60 minutes or more of PA after school on week days and on weekend’s respectively. This PA consisted mostly of running and ball games. Only 10 percent of participants had commenced with menarche Conclusion Findings have highlighted the need for specifically targeted FMS interventions at an early age in female learners from previously disadvantaged communities. Both a product and process FMS assessment is warranted as this facilitates deductions about movement proficiency levels. A FMS proficiency assessment protocol is needed for South African children which is internationally comparable. Childhood overweight and obesity impacts FMS proficiency and should be addressed in future research. Cultural norms, gender stereotypes and sport management structures at primary school level seem to be affecting FMS proficiency and should be addressed in future research
- Full Text:
- Date Issued: 2014
- Authors: Kahts, Samantha Andrea
- Date: 2014
- Subjects: Movement therapy for children -- South Africa -- Port Elizabeth , Exercise therapy -- South Africa -- Port Elizabeth , Kinesiology -- Social aspects -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10114 , http://hdl.handle.net/10948/d1021035
- Description: Problem Statement A lack of fundamental movement skill (FMS) proficiency in children can contribute to decreased physical activity (PA) levels, increased adiposity and poor acquisition of specialised sport specific movement skills. To prevent the latter, the identification of FMS status in early and middle childhood years is needed for targeted and specific interventions. Against the backdrop of physical education being omitted from the South African school curriculum, the presence of a patriarchal society, gender sporting stereotyping, high levels of unemployment and low education levels; the assessment of FMS status is particularly warranted. Aim of Study The primary aim of this study was to assess the FMS proficiency of girls aged 9-to-12 years from previously disadvantaged communities within Nelson Mandela Bay. Methodology A descriptive-exploratory-contextual study design, employing quantitative assessment techniques, was utilized. The sample comprised of 227 girls. Convenience sampling was employed. Testing consisted of FMS proficiency tests in the 20m and 40m sprint, standing long jump, throwing for distance, catching, static balance and throwing for accuracy. FMS process scores were assessed with the body component (BC) and Test of Gross Motor Development II (TGMD II) approaches. Anthropometric measurements of the standing and seated height, mass, arm span and leg length were additionally measured. Microsoft Excel® and Statistica® were used for descriptive and inferential statistical analysis. In the case of significant ANOVA results, the Scheffe post hoc test was used for pairwise comparisons. Statistical significance was set at p<.05 and practical significance (Cohen’s d) was set at d>.2. Pearson Correlation Coefficient identified statistical and practical correlations between two variables and chi square was applied to indicate differences in frequency distribution tables. Cramer’s V values were applied to determine practical significance in the case where statistical significant differences were identified between sets of frequency distributions The BC approach indicated that most participants could not proficiently perform the run for speed (94.71 percent), standing long jump (96.9 percent) or throw for distance (83.56 percent). Only the catch was performed proficiently (91.19 percent). TGMD II results for the present study indicated that participants’ run for speed (100 percent) and catch (96.92 percent) were performed proficiently and their standing long jump (93.78 percent) and throw for distance (83.56 percent) process scores were performed least proficiently. Only the catch composite BC scores had a statistically (df=1.31; f=3.24; p=.024) and practically significant (d=0.82) improvement in the BC scores between the age groups 9 and 12 years. Only the standing long jump, throw for distance and throw for accuracy product scores improved statically and practically significantly with aging (p<.05; d>.2). Hence the further participants jumped, the faster they ran. Standing and seated height, weight and arm span improved statistically and practically significantly with age (p<.05; d>.2). All anthropometric variables, except for leg length, had a positive medium correlation (r=.335 to r=.439) with balance errors and this was only in 12 year olds. The throw for distance product scores had a medium correlation to seated height (r=.32) and arm span (r=.33). The run for speed had a medium correlation (r=.313) with mass. According to the IOTF classifications 24.67 percent of children were overweight and 7.49 percent of children were obese. Statistically significant differences were found for the run for speed (df=224; f=27.07; p=2.9E-11) and standing long jump (df=224; f=15.68; p=4.2E-07) when comparing product scores to normal weight, overweight and obese participants. These differences were furthermore found to be of medium to large practical significance between the normal and obese participants for the run for speed (d=0.61 to d=1.77) and Standing Long Jump (d=0.40 to d=1.33). On average 50 percent and 55 percent of participants partook 60 minutes or more of PA after school on week days and on weekend’s respectively. This PA consisted mostly of running and ball games. Only 10 percent of participants had commenced with menarche Conclusion Findings have highlighted the need for specifically targeted FMS interventions at an early age in female learners from previously disadvantaged communities. Both a product and process FMS assessment is warranted as this facilitates deductions about movement proficiency levels. A FMS proficiency assessment protocol is needed for South African children which is internationally comparable. Childhood overweight and obesity impacts FMS proficiency and should be addressed in future research. Cultural norms, gender stereotypes and sport management structures at primary school level seem to be affecting FMS proficiency and should be addressed in future research
- Full Text:
- Date Issued: 2014
General structural and functional features of molecular chaperones:
- Edkins, Adrienne L, Boshoff, Aileen
- Authors: Edkins, Adrienne L , Boshoff, Aileen
- Date: 2014
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/164808 , vital:41174 , ISBN 978-94-007-7437-7 , DOI: 10.1007/978-94-007-7438-4_2
- Description: Molecular chaperones are a group of structurally diverse and highly conserved ubiquitous proteins. They play crucial roles in facilitating the correct folding of proteins in vivo by preventing protein aggregation or facilitating the appropriate folding and assembly of proteins. Heat shock proteins form the major class of molecular chaperones that are responsible for protein folding events in the cell. This is achieved by ATP-dependent (folding machines) or ATP-independent mechanisms (holders). Heat shock proteins are induced by a variety of stresses, besides heat shock. The large and varied heat shock protein class is categorised into several subfamilies based on their sizes in kDa namely, small Hsps (HSPB), Hsp40 (DNAJ), Hsp60 (HSPD/E; Chaperonins), Hsp70 (HSPA), Hsp90 (HSPC), and Hsp100.
- Full Text:
- Date Issued: 2014
- Authors: Edkins, Adrienne L , Boshoff, Aileen
- Date: 2014
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/164808 , vital:41174 , ISBN 978-94-007-7437-7 , DOI: 10.1007/978-94-007-7438-4_2
- Description: Molecular chaperones are a group of structurally diverse and highly conserved ubiquitous proteins. They play crucial roles in facilitating the correct folding of proteins in vivo by preventing protein aggregation or facilitating the appropriate folding and assembly of proteins. Heat shock proteins form the major class of molecular chaperones that are responsible for protein folding events in the cell. This is achieved by ATP-dependent (folding machines) or ATP-independent mechanisms (holders). Heat shock proteins are induced by a variety of stresses, besides heat shock. The large and varied heat shock protein class is categorised into several subfamilies based on their sizes in kDa namely, small Hsps (HSPB), Hsp40 (DNAJ), Hsp60 (HSPD/E; Chaperonins), Hsp70 (HSPA), Hsp90 (HSPC), and Hsp100.
- Full Text:
- Date Issued: 2014
Genesis of BIF-hosted hematite iron ore deposits in the central part of the Maremane anticline, Northern Cape Province, South Africa
- Authors: Land, Jarred
- Date: 2014
- Subjects: Hematite -- South Africa -- Northern Cape , Anticlines -- South Africa -- Northern Cape , Geology, Stratigraphic -- Proterozoic , Hydrothermal deposits -- Northern Cape , Rare earth metals -- Northern Cape , Iron ores -- Geology -- Northern Cape , Transvaal Supergroup (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5095 , http://hdl.handle.net/10962/d1020905
- Description: The Paleoproterozoic Transvaal Supergroup in the Northern Cape Province of South Africa is host to high-grade BIF-hosted hematite iron-ore deposits and is the country’s most important source of iron to date. Previous work has failed to provide a robust and all-inclusive genetic model for such deposits in the Transvaal Supergroup; in particular, the role of hydrothermal processes in ore-genesis has not been adequately clarified. Recent studies by the author have produced evidence for hydrothermal alteration in shales (Olifantshoek Supergroup) stratigraphically overlying the iron-ore intervals; this has highlighted the need to reassess current ore-forming models which place residual supergene processes at the core of oregenesis. This thesis focuses on providing new insights into the processes responsible for the genesis of hematite iron ores in the Maremane anticline through the use of newly available exploration drill-core material from the centre of the anticline. The study involved standard mineralogical investigations using transmitted/reflected light microscopy as well as instrumental techniques (XRD, EPMA); and the employment of traditional whole-rock geochemical analysis on samples collected from two boreholes drilled in the centre of the Maremane anticline, Northern Cape Province. Rare earth element analysis (via ICP-MS) and oxygen isotope data from hematite separates complement the whole-rock data. Iron-ore mineralisation examined in this thesis is typified by the dominance of Fe-oxide (as hematite), which reaches whole-rock abundances of up to 98 wt. % Fe₂O₃. Textural and whole-rock geochemical variations in the ores likely reflect a variable protolith, from BIF to Fe-bearing shale. A standard supergene model invoking immobility and residual enrichment of iron is called into question on the basis of the relative degrees of enrichment recorded in the ores with respect to other, traditionally immobile elements during chemical weathering, such as Al₂O₃ and TiO₂. Furthermore, the apparently conservative behaviour of REE in the Fe ore (i.e. low-grade and high-grade iron ore) further emphasises the variable protolith theory. Hydrothermally-induced ferruginisation is suggested to post-date the deposition of the post-Transvaal Olifantshoek shales, and is likely to be linked to a sub-surface transgressive hydrothermal event which indiscriminately transforms both shale and BIF into Fe-ore. A revised, hydrothermal model for the formation of BIF-hosted high-grade hematite iron ore deposits in the central part of the Maremane anticline is proposed, and some ideas of the author for further follow-up research are presented.
- Full Text:
- Date Issued: 2014
- Authors: Land, Jarred
- Date: 2014
- Subjects: Hematite -- South Africa -- Northern Cape , Anticlines -- South Africa -- Northern Cape , Geology, Stratigraphic -- Proterozoic , Hydrothermal deposits -- Northern Cape , Rare earth metals -- Northern Cape , Iron ores -- Geology -- Northern Cape , Transvaal Supergroup (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5095 , http://hdl.handle.net/10962/d1020905
- Description: The Paleoproterozoic Transvaal Supergroup in the Northern Cape Province of South Africa is host to high-grade BIF-hosted hematite iron-ore deposits and is the country’s most important source of iron to date. Previous work has failed to provide a robust and all-inclusive genetic model for such deposits in the Transvaal Supergroup; in particular, the role of hydrothermal processes in ore-genesis has not been adequately clarified. Recent studies by the author have produced evidence for hydrothermal alteration in shales (Olifantshoek Supergroup) stratigraphically overlying the iron-ore intervals; this has highlighted the need to reassess current ore-forming models which place residual supergene processes at the core of oregenesis. This thesis focuses on providing new insights into the processes responsible for the genesis of hematite iron ores in the Maremane anticline through the use of newly available exploration drill-core material from the centre of the anticline. The study involved standard mineralogical investigations using transmitted/reflected light microscopy as well as instrumental techniques (XRD, EPMA); and the employment of traditional whole-rock geochemical analysis on samples collected from two boreholes drilled in the centre of the Maremane anticline, Northern Cape Province. Rare earth element analysis (via ICP-MS) and oxygen isotope data from hematite separates complement the whole-rock data. Iron-ore mineralisation examined in this thesis is typified by the dominance of Fe-oxide (as hematite), which reaches whole-rock abundances of up to 98 wt. % Fe₂O₃. Textural and whole-rock geochemical variations in the ores likely reflect a variable protolith, from BIF to Fe-bearing shale. A standard supergene model invoking immobility and residual enrichment of iron is called into question on the basis of the relative degrees of enrichment recorded in the ores with respect to other, traditionally immobile elements during chemical weathering, such as Al₂O₃ and TiO₂. Furthermore, the apparently conservative behaviour of REE in the Fe ore (i.e. low-grade and high-grade iron ore) further emphasises the variable protolith theory. Hydrothermally-induced ferruginisation is suggested to post-date the deposition of the post-Transvaal Olifantshoek shales, and is likely to be linked to a sub-surface transgressive hydrothermal event which indiscriminately transforms both shale and BIF into Fe-ore. A revised, hydrothermal model for the formation of BIF-hosted high-grade hematite iron ore deposits in the central part of the Maremane anticline is proposed, and some ideas of the author for further follow-up research are presented.
- Full Text:
- Date Issued: 2014
Genesis of karst-hosted manganese ores of the Postmasburg Manganese Field, South Africa with emphasis on evidence for hydrothermal processes
- Authors: Fairey, Brenton John
- Date: 2014
- Subjects: Karst -- South Africa -- Postmasburg , Manganese ores -- South Africa -- Postmasburg , Hydrothermal alteration -- South Africa -- Postmasburg , Manganese mines and mining -- South Africa -- Northern Cape , Petrology , Mineralogical chemistry , Geochemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5094 , http://hdl.handle.net/10962/d1020904
- Description: The Postmasburg Manganese Field (PMF), located in the Northern Cape Province of South Africa, once represented one of the largest sources of manganese ore worldwide. However, the discovery of the giant manganese deposits of the Kalahari Manganese Field (KMF) led to the gradual decline in manganese mining activity in the PMF. Two belts of manganese ore deposits have been distinguished in the PMF, namely the Western Belt of ferruginous manganese ores and the Eastern Belt of siliceous manganese ores. Prevailing models of ore formation in these two belts invoke karstification of manganese-rich dolomites and residual accumulation of manganese wad which later underwent diagenetic and low-grade metamorphic processes. For the most part, the role of hydrothermal processes in ore formation and metasomatic alteration is not addressed. The identification of an abundance of common and some rare Al-, Na-, K- and Ba-bearing minerals, particularly aegirine, albite, microcline, banalsite, sérandite-pectolite, paragonite and natrolite in the PMF ores studied in this thesis, is indicative of the influence of hydrothermal activity. Enrichments in Na, K and/or Ba in the ores are generally on a percentage level for the majority of samples analysed through bulk-rock techniques. The discovery of a Ba-Mn arsenate/vanadate similar to gamagarite may also indicate that the hydrothermal fluid affecting the ores was not only alkali-rich but also probably contained some As and V. The fluid was likely to be oxidized and alkaline in nature and is thought to have been a mature basinal brine. Various replacement textures, particularly of Na- and Krich minerals by Ba-bearing phases, suggest sequential deposition of gangue as well as oreminerals from the hydrothermal fluid, with Ba phases being deposited at a later stage. The stratigraphic variability of the studied ores and the deviation of their character from the pigeon-hole-type classification of ferruginous and siliceous ores in the literature, suggests that a re-evaluation of genetic models is warranted. The discovery of hydrothermallydeposited alkali-rich assemblages in the PMF and KMF provides grounding for further investigation into a possible regional-scale hydrothermal event at least re-constituting the ores. Some shortcomings in previous works include disregard for the highly variable nature of the PMF deposits, the effects of hydrothermal activity of the ores and the existence of stratigraphic discrepancies. This study provides a single, broad model for the development of all manganese deposits of the PMF. The source of metals is attributed to all formations that stratigraphically overly the Reivilo Formation of the Campbellrand Subgroup (including the Reivilo Formation itself). The main process by which metals are accumulated is attributed to karstification of the dolomites. The interaction of oxidized, alkaline brines with the ores is considered and the overlying Asbestos Hills Subgroup BIF is suggested as a potential source of alkali metals.
- Full Text:
- Date Issued: 2014
- Authors: Fairey, Brenton John
- Date: 2014
- Subjects: Karst -- South Africa -- Postmasburg , Manganese ores -- South Africa -- Postmasburg , Hydrothermal alteration -- South Africa -- Postmasburg , Manganese mines and mining -- South Africa -- Northern Cape , Petrology , Mineralogical chemistry , Geochemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5094 , http://hdl.handle.net/10962/d1020904
- Description: The Postmasburg Manganese Field (PMF), located in the Northern Cape Province of South Africa, once represented one of the largest sources of manganese ore worldwide. However, the discovery of the giant manganese deposits of the Kalahari Manganese Field (KMF) led to the gradual decline in manganese mining activity in the PMF. Two belts of manganese ore deposits have been distinguished in the PMF, namely the Western Belt of ferruginous manganese ores and the Eastern Belt of siliceous manganese ores. Prevailing models of ore formation in these two belts invoke karstification of manganese-rich dolomites and residual accumulation of manganese wad which later underwent diagenetic and low-grade metamorphic processes. For the most part, the role of hydrothermal processes in ore formation and metasomatic alteration is not addressed. The identification of an abundance of common and some rare Al-, Na-, K- and Ba-bearing minerals, particularly aegirine, albite, microcline, banalsite, sérandite-pectolite, paragonite and natrolite in the PMF ores studied in this thesis, is indicative of the influence of hydrothermal activity. Enrichments in Na, K and/or Ba in the ores are generally on a percentage level for the majority of samples analysed through bulk-rock techniques. The discovery of a Ba-Mn arsenate/vanadate similar to gamagarite may also indicate that the hydrothermal fluid affecting the ores was not only alkali-rich but also probably contained some As and V. The fluid was likely to be oxidized and alkaline in nature and is thought to have been a mature basinal brine. Various replacement textures, particularly of Na- and Krich minerals by Ba-bearing phases, suggest sequential deposition of gangue as well as oreminerals from the hydrothermal fluid, with Ba phases being deposited at a later stage. The stratigraphic variability of the studied ores and the deviation of their character from the pigeon-hole-type classification of ferruginous and siliceous ores in the literature, suggests that a re-evaluation of genetic models is warranted. The discovery of hydrothermallydeposited alkali-rich assemblages in the PMF and KMF provides grounding for further investigation into a possible regional-scale hydrothermal event at least re-constituting the ores. Some shortcomings in previous works include disregard for the highly variable nature of the PMF deposits, the effects of hydrothermal activity of the ores and the existence of stratigraphic discrepancies. This study provides a single, broad model for the development of all manganese deposits of the PMF. The source of metals is attributed to all formations that stratigraphically overly the Reivilo Formation of the Campbellrand Subgroup (including the Reivilo Formation itself). The main process by which metals are accumulated is attributed to karstification of the dolomites. The interaction of oxidized, alkaline brines with the ores is considered and the overlying Asbestos Hills Subgroup BIF is suggested as a potential source of alkali metals.
- Full Text:
- Date Issued: 2014
Genetic and biological characterisation of a novel South African Plutella xylostella granulovirus (PlxyGV) isolate
- Authors: Abdulkadir, Fatima
- Date: 2014
- Subjects: Diamondback moth , Diamondback moth -- Control -- South Africa , Plutellidae -- Control -- South Africa , Baculoviruses , Cruciferae -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4113 , http://hdl.handle.net/10962/d1013059
- Description: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is an important pest of cruciferous crops worldwide. The prolonged use of synthetic chemical insecticides as a primary means of control has resulted in the development of resistance in pest populations. In addition, the pest has also evolved resistance to the bacterial insecticidal protein of Bacillus thuringiensis which is also widely used as a method of control. Baculoviruses are considered as effective alternatives to conventional methods of control when incorporated into integrated pest management (IPM) programmes. These viruses target the larval stages of insects, are generally host-specific and are safe for use in the environment. This study aimed to isolate a baculovirus from a laboratory-reared P. xylostella colony, characterise it genetically and then evaluate its virulence against neonate and fourth instar larvae. A laboratory colony of P. xylostella was established using pupae and asymptomatic larvae collected from a cabbage plantation outside Grahamstown in the Eastern Cape province of South Africa. The colony flourished in the laboratory due to prime conditions and availability of food. The duration of development from egg to adult was determined by observation and imaging of the various life stages. The mean developmental time from egg to adult was observed to be 14.59 ± 0.21 days. The population of the insects increased rapidly in number leading to overcrowding of the insect colony, and hence appearance of larvae with viral symptoms. Occlusion bodies (OBs) were extracted from symptomatic larval cadavers and purified by glycerol gradient centrifugation. Analysis of the purified OBs by transmission electron microscopy revealed the presence of a granulovirus which was named PlxyGV-SA. The virus isolate was genetically characterised by restriction endonuclease analysis of the genomic DNA, and PCR amplification and sequencing of selected viral genes. The complete genome sequence of a Japanese P. xylostella granulovirus isolate, PlxyGV-Japan, has been deposited on the GenBank database providing a reference strain for comparison with DNA profiles and selected gene sequences of PlxyGV-SA. BLAST analysis of the granulin gene confirmed the isolation of a novel South African PlxyGV isolate. Comparison of the restriction profiles of PlxyGV-SA with profiles of PlxyGV-Japan and other documented PlxyGV profiles obtained by agarose gel electrophoresis revealed that PlxyGV-SA is a genetically distinct isolate. The data obtained from the sequencing and alignment of ecdysteroid UDP-glucosyltransferase (egt), late expression factor 8 (lef-8) and late expression factor 9 (lef-9) genes with those of PlxyGV-Japan also showed that PlxyGV-SA is a genetically different isolate. In order to determine the biological activity of PlxyGV-SA against neonate and fourth instar P. xylostella larvae, surface dose bioassays were conducted. The median lethal concentration of the virus required to kill 50% (LC₅₀) and 90% (LC₉₀) of the larvae was estimated by feeding insects with a range of doses. In addition, the time to kill 50% of the larvae (LT₅₀) was determined by feeding insects with the LC₉₀ concentration. Larval mortality was monitored daily until pupation. The data obtained from the dose response assays were subjected to probit analysis using Proban statistical software. The time response was determined using GraphPad Prism software (version 6.0). The LC₅₀ and LC₉₀ values for the neonate larvae were 3.56 × 10⁵ and 1.14 × 10⁷ OBs/ml respectively. The LT₅₀ was determined to be 104 hours. The neonate larvae were found to be more susceptible to infection than the fourth instar larvae with the same virus concentration. The concentrations used for the neonate larvae assay did not have a significant effect on the fourth instar as no mortality was recorded. This is the first study to describe a novel South African PlxyGV isolate and the results suggest that PlxyGV-SA has significant potential for development as an effective biopesticide for the control of P. xylostella in the field.
- Full Text:
- Date Issued: 2014
- Authors: Abdulkadir, Fatima
- Date: 2014
- Subjects: Diamondback moth , Diamondback moth -- Control -- South Africa , Plutellidae -- Control -- South Africa , Baculoviruses , Cruciferae -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4113 , http://hdl.handle.net/10962/d1013059
- Description: The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is an important pest of cruciferous crops worldwide. The prolonged use of synthetic chemical insecticides as a primary means of control has resulted in the development of resistance in pest populations. In addition, the pest has also evolved resistance to the bacterial insecticidal protein of Bacillus thuringiensis which is also widely used as a method of control. Baculoviruses are considered as effective alternatives to conventional methods of control when incorporated into integrated pest management (IPM) programmes. These viruses target the larval stages of insects, are generally host-specific and are safe for use in the environment. This study aimed to isolate a baculovirus from a laboratory-reared P. xylostella colony, characterise it genetically and then evaluate its virulence against neonate and fourth instar larvae. A laboratory colony of P. xylostella was established using pupae and asymptomatic larvae collected from a cabbage plantation outside Grahamstown in the Eastern Cape province of South Africa. The colony flourished in the laboratory due to prime conditions and availability of food. The duration of development from egg to adult was determined by observation and imaging of the various life stages. The mean developmental time from egg to adult was observed to be 14.59 ± 0.21 days. The population of the insects increased rapidly in number leading to overcrowding of the insect colony, and hence appearance of larvae with viral symptoms. Occlusion bodies (OBs) were extracted from symptomatic larval cadavers and purified by glycerol gradient centrifugation. Analysis of the purified OBs by transmission electron microscopy revealed the presence of a granulovirus which was named PlxyGV-SA. The virus isolate was genetically characterised by restriction endonuclease analysis of the genomic DNA, and PCR amplification and sequencing of selected viral genes. The complete genome sequence of a Japanese P. xylostella granulovirus isolate, PlxyGV-Japan, has been deposited on the GenBank database providing a reference strain for comparison with DNA profiles and selected gene sequences of PlxyGV-SA. BLAST analysis of the granulin gene confirmed the isolation of a novel South African PlxyGV isolate. Comparison of the restriction profiles of PlxyGV-SA with profiles of PlxyGV-Japan and other documented PlxyGV profiles obtained by agarose gel electrophoresis revealed that PlxyGV-SA is a genetically distinct isolate. The data obtained from the sequencing and alignment of ecdysteroid UDP-glucosyltransferase (egt), late expression factor 8 (lef-8) and late expression factor 9 (lef-9) genes with those of PlxyGV-Japan also showed that PlxyGV-SA is a genetically different isolate. In order to determine the biological activity of PlxyGV-SA against neonate and fourth instar P. xylostella larvae, surface dose bioassays were conducted. The median lethal concentration of the virus required to kill 50% (LC₅₀) and 90% (LC₉₀) of the larvae was estimated by feeding insects with a range of doses. In addition, the time to kill 50% of the larvae (LT₅₀) was determined by feeding insects with the LC₉₀ concentration. Larval mortality was monitored daily until pupation. The data obtained from the dose response assays were subjected to probit analysis using Proban statistical software. The time response was determined using GraphPad Prism software (version 6.0). The LC₅₀ and LC₉₀ values for the neonate larvae were 3.56 × 10⁵ and 1.14 × 10⁷ OBs/ml respectively. The LT₅₀ was determined to be 104 hours. The neonate larvae were found to be more susceptible to infection than the fourth instar larvae with the same virus concentration. The concentrations used for the neonate larvae assay did not have a significant effect on the fourth instar as no mortality was recorded. This is the first study to describe a novel South African PlxyGV isolate and the results suggest that PlxyGV-SA has significant potential for development as an effective biopesticide for the control of P. xylostella in the field.
- Full Text:
- Date Issued: 2014
Genetic and morphometric variation of Octopus vulgaris in the Benguela Current region
- Authors: De Beer, Chénelle Lesley
- Date: 2014
- Subjects: Common octopus -- Africa, Southern , Common octopus -- Genetics , Common octopus -- Morphology , Common octopus -- Geographical distribution , Variation (Biology) , Benguela Current
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5362 , http://hdl.handle.net/10962/d1012971
- Description: The Benguela Current is a cold eastern boundary current located on the south-western coast of the African continent. The establishment of its present day features approximately two million years ago has triggered allopatric events which have driven genetic and/or phenotypic differentiation in many of the warm-temperate organisms that previously had continuous distributions along the south and west coast of southern Africa. However, since many of these species have responded differently, despite similar isolation times, research in this region provides a unique opportunity to increase our understanding of evolutionary processes. The common octopus (Octopus vulgaris, Cuvier 1797) is a coastal, sedentary species, inhabiting coral reefs or rocky environments at depths of up to a 100m. It is considered to be one of the most extensively studied cephalopod species due to its worldwide distribution. However, very little research has been conducted on O. vulgaris in southern Africa. In order to gain a holistic understanding of the effects of the Benguela Current on population connectivity, genetic and phenotypic diversity, and evolutionary history of O. vulgaris, a comparative genetic and morphological study was conducted across the Benguela region. A total of 168 specimens of O. vulgaris were collected from four different regions across the Benguela system. A small tissue sample was preserved in ethanol for molecular analysis, and the specimen was frozen whole for morphometric analysis in the laboratory. Octopus vulgaris genetic population structure and evolutionary history was investigated using a 580bp fragment of the mitochondrial cytochrome b (cytb) gene for 76 individuals located within the Benguela region, yielding 10 different haplotypes. AMOVA and pairwise FST analyses revealed significant genetic differentiation suggesting a northern-southern Benguela divergence. Estimates of time since most recent common ancestor, based on biogeographical calibrators and coalescent analyses, indicated that isolation between the Angolan and South African population occurred between ~231 Ka and 1 Ma. Mismatch distribution analyses revealed a past population expansion within the South African O. vulgaris roughly 129.31 Ka, whilst Bayesian skyline plots were indicative of gradual demographic growth within the Angolan population in the last ~100 Ka. Observed O. vulgaris population structure and demographic history was likely the result of historical climate-induced change within the system. Reconstruction of phylogenetic relationships within the Octopus genus, using cytb and COI suggest that O. vulgaris is not a monophyletic group and a major systematic revision is required. Furthermore, unidentified individuals from South Africa were found to group with species from Indo-West Pacific Oceans and were therefore considered to have been translocated through ballast water from Asia. While the molecular analysis indicated a significant northern-southern Benguela structure results from the principle component analysis (PCA) and discriminate function analysis (DFA) were unable to distinguish between O. vulgaris from different sampling localities throughout the Benguela Current region based on soft-parts, hard-parts and meristic characters. The lack of phenotypic variation, despite significant genetic divergence, highlights the importance of multi-method approaches in gaining a holistic understanding of the taxonomy and biogeography of species.
- Full Text:
- Date Issued: 2014
- Authors: De Beer, Chénelle Lesley
- Date: 2014
- Subjects: Common octopus -- Africa, Southern , Common octopus -- Genetics , Common octopus -- Morphology , Common octopus -- Geographical distribution , Variation (Biology) , Benguela Current
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5362 , http://hdl.handle.net/10962/d1012971
- Description: The Benguela Current is a cold eastern boundary current located on the south-western coast of the African continent. The establishment of its present day features approximately two million years ago has triggered allopatric events which have driven genetic and/or phenotypic differentiation in many of the warm-temperate organisms that previously had continuous distributions along the south and west coast of southern Africa. However, since many of these species have responded differently, despite similar isolation times, research in this region provides a unique opportunity to increase our understanding of evolutionary processes. The common octopus (Octopus vulgaris, Cuvier 1797) is a coastal, sedentary species, inhabiting coral reefs or rocky environments at depths of up to a 100m. It is considered to be one of the most extensively studied cephalopod species due to its worldwide distribution. However, very little research has been conducted on O. vulgaris in southern Africa. In order to gain a holistic understanding of the effects of the Benguela Current on population connectivity, genetic and phenotypic diversity, and evolutionary history of O. vulgaris, a comparative genetic and morphological study was conducted across the Benguela region. A total of 168 specimens of O. vulgaris were collected from four different regions across the Benguela system. A small tissue sample was preserved in ethanol for molecular analysis, and the specimen was frozen whole for morphometric analysis in the laboratory. Octopus vulgaris genetic population structure and evolutionary history was investigated using a 580bp fragment of the mitochondrial cytochrome b (cytb) gene for 76 individuals located within the Benguela region, yielding 10 different haplotypes. AMOVA and pairwise FST analyses revealed significant genetic differentiation suggesting a northern-southern Benguela divergence. Estimates of time since most recent common ancestor, based on biogeographical calibrators and coalescent analyses, indicated that isolation between the Angolan and South African population occurred between ~231 Ka and 1 Ma. Mismatch distribution analyses revealed a past population expansion within the South African O. vulgaris roughly 129.31 Ka, whilst Bayesian skyline plots were indicative of gradual demographic growth within the Angolan population in the last ~100 Ka. Observed O. vulgaris population structure and demographic history was likely the result of historical climate-induced change within the system. Reconstruction of phylogenetic relationships within the Octopus genus, using cytb and COI suggest that O. vulgaris is not a monophyletic group and a major systematic revision is required. Furthermore, unidentified individuals from South Africa were found to group with species from Indo-West Pacific Oceans and were therefore considered to have been translocated through ballast water from Asia. While the molecular analysis indicated a significant northern-southern Benguela structure results from the principle component analysis (PCA) and discriminate function analysis (DFA) were unable to distinguish between O. vulgaris from different sampling localities throughout the Benguela Current region based on soft-parts, hard-parts and meristic characters. The lack of phenotypic variation, despite significant genetic divergence, highlights the importance of multi-method approaches in gaining a holistic understanding of the taxonomy and biogeography of species.
- Full Text:
- Date Issued: 2014