Mineralogical and geochemical constraints on the origin, alteration history and metallogenic significance of the Manganore iron-formation, Northern Cape Province, South Africa
- Authors: Papadopoulos, Vlassis
- Date: 2017
- Subjects: Banded iron formation , Transvaal Supergroup (South Africa) , Groups (Stratigraphy) South Africa , Lithostratigraphy , Petrology South Africa , Geochemistry South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65189 , vital:28702
- Description: The Manganore iron-formation (MIF) of the Transvaal Supergroup is host to the most important high-grade iron ore bodies in South Africa. Prevailing models for ore genesis invoke supergene processes performing during a long period of erosion, oxidation and weathering under tropical lateritic conditions while the role of potential hydrothermal processes is not addressed. Lack of detailed petrographical and geochemical data necessitated reexamination of the MIF through new and existing drill core exploration material. Thorough petrographical investigation revealed a multi-event complex alteration history involving hydrothermal activity. Iron and silica mobility during alteration is demonstrated by a series of replacement, overprinting, crosscutting textures, extensive silicification and hematitization. Metasomatized textures such as pseudomorphs of primary magnetite, carbonate minerals and chert pods/lenses point to an alteration occurring in layer- controlled fronts and link stratigraphically the MIF to Kuruman and Griquatown iron- formations. Whole-rock geochemical data verify textural observations suggesting strong enrichment of iron or silica in meter-scale horizons, expressed by different generations of quartz and hematite. High-grade iron ore is highly enriched in TiO2 and Al2O3 compared to the protolith while both BIF and iron ore display highly increased concentrations of trace elements (transition metals and HFSE). Oxygen isotopes from different quartz textures reveal little to none isotopic exchangement during alteration whereas O isotopes from hematite are in concert to values from literature and suggest two different generations of hematite. A total of 20 minerals apart from quartz and hematite were documented. An earlier alkali/HFSE alteration event that is believed to have affected the overlying Gamagara shales is recorded in the BIF by the presence of muscovite, apatite, rutile, zircon and xenotime. A later and possibly ongoing event of succeeding hydrothermal pulses involves mainly sulphates (gypsum, baryte, celestine), pyrite, carbonates (siderite, calcite) and silicates (berthierine and tourmaline). Alkali-bearing brines persistently exploit the BIF mainly through karstification-related secondary porosity, are evidently carrying iron and are proposed to participate in or control the iron enrichment by facilitating removal of silica. The source of metals, sulfur and carbon is attributed to the underlying Campbellrand dolomites and especially to the upper Gamogaan Formation. The unconformable contact between BIF and the overlying shales is suggested as a suitable fluid conduit for the development of the observed BIF and shale-derived high-grade hematite iron ore.
- Full Text:
- Authors: Papadopoulos, Vlassis
- Date: 2017
- Subjects: Banded iron formation , Transvaal Supergroup (South Africa) , Groups (Stratigraphy) South Africa , Lithostratigraphy , Petrology South Africa , Geochemistry South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/65189 , vital:28702
- Description: The Manganore iron-formation (MIF) of the Transvaal Supergroup is host to the most important high-grade iron ore bodies in South Africa. Prevailing models for ore genesis invoke supergene processes performing during a long period of erosion, oxidation and weathering under tropical lateritic conditions while the role of potential hydrothermal processes is not addressed. Lack of detailed petrographical and geochemical data necessitated reexamination of the MIF through new and existing drill core exploration material. Thorough petrographical investigation revealed a multi-event complex alteration history involving hydrothermal activity. Iron and silica mobility during alteration is demonstrated by a series of replacement, overprinting, crosscutting textures, extensive silicification and hematitization. Metasomatized textures such as pseudomorphs of primary magnetite, carbonate minerals and chert pods/lenses point to an alteration occurring in layer- controlled fronts and link stratigraphically the MIF to Kuruman and Griquatown iron- formations. Whole-rock geochemical data verify textural observations suggesting strong enrichment of iron or silica in meter-scale horizons, expressed by different generations of quartz and hematite. High-grade iron ore is highly enriched in TiO2 and Al2O3 compared to the protolith while both BIF and iron ore display highly increased concentrations of trace elements (transition metals and HFSE). Oxygen isotopes from different quartz textures reveal little to none isotopic exchangement during alteration whereas O isotopes from hematite are in concert to values from literature and suggest two different generations of hematite. A total of 20 minerals apart from quartz and hematite were documented. An earlier alkali/HFSE alteration event that is believed to have affected the overlying Gamagara shales is recorded in the BIF by the presence of muscovite, apatite, rutile, zircon and xenotime. A later and possibly ongoing event of succeeding hydrothermal pulses involves mainly sulphates (gypsum, baryte, celestine), pyrite, carbonates (siderite, calcite) and silicates (berthierine and tourmaline). Alkali-bearing brines persistently exploit the BIF mainly through karstification-related secondary porosity, are evidently carrying iron and are proposed to participate in or control the iron enrichment by facilitating removal of silica. The source of metals, sulfur and carbon is attributed to the underlying Campbellrand dolomites and especially to the upper Gamogaan Formation. The unconformable contact between BIF and the overlying shales is suggested as a suitable fluid conduit for the development of the observed BIF and shale-derived high-grade hematite iron ore.
- Full Text:
Mineralogical variation in the basal Upper Zone, Bushveld Igneous Complex, South Africa: implications for ore genesis and mineral extraction
- Van Huyssteen, Darryn Ashley
- Authors: Van Huyssteen, Darryn Ashley
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5060 , vital:20762
- Full Text:
- Authors: Van Huyssteen, Darryn Ashley
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5060 , vital:20762
- Full Text:
Mineralogy and geochemistry of structurally-controlled metasomatic alteration of carbonate-rich manganese ore at Mamatwan Mine, Kalahari Manganese Field
- Authors: Harawa, Esau Tonderai
- Date: 2017
- Subjects: Metasomatism (Mineralogy) , Manganese ores -- Geology -- South Africa , Geology -- South Africa , Mamatwan Mine (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4717 , vital:20715
- Description: The Kalahari Manganese Field (KMF) located in the Northern Cape Province about 700km south west of Johannesburg contains 80% of the world manganese ore reserves. Mamatwan Mine is hosted within the low grade Mamatwan type ore and is located in the southernmost tip of the KMF. This mine is an open pit mine which is divided into three benches namely the top cut, middle cut and bottom cut. These three benches are structurally controlled by faults which influence the overall grade of the manganese ore. This study is a follow up work to the previous two studies carried out at Wessels Mine and Mamatwan Mine by (Gutzmer and Beukes) in 1995 and 1996 respectively with regards to alteration processes around fault controlled systems in which they concluded that epithermal fluids caused local reduction and bleaching of ore followed by oxidation and carbonate leaching of manganese ore through ascending oxidized groundwater. Metasomatic activity around fault controlled systems is controlled by three main processes namely redistribution, enrichment and depletion. These processes are determined by mobility/immobility of elements from the fault which are introduced into the pre-existing braunite carbonate rich ore. Elements such as Ca, Mg, Si, Fe, C and Mn interact with pre-existing ore due to temperature, fluid pressure, physico-chemical property of fluid gradient. Structurally, faulting and folding contribute to the movement of elements as one end of the system gets depleted the other end of the system gets enriched and vice versa. To better understand this metasomatic activity, it is crucial to conduct mass balance studies of these elements. Grant (1986) introduced the isocon diagram which is a modification of Gresen’s equation (1967) to ascertain which elements are directly or indirectly related to alteration through enrichment and depletion of Ca, Mg, Si, Fe, C and Mn. As the section approaches from altered to less altered manganese ore the mineral chemistry gradually changes from a manganese rich matrix composed of manganomelane and todorokite to a carbonate rich matrix composed of braunite, dolomite, kutnohorite and Mn-rich calcites.
- Full Text:
- Authors: Harawa, Esau Tonderai
- Date: 2017
- Subjects: Metasomatism (Mineralogy) , Manganese ores -- Geology -- South Africa , Geology -- South Africa , Mamatwan Mine (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4717 , vital:20715
- Description: The Kalahari Manganese Field (KMF) located in the Northern Cape Province about 700km south west of Johannesburg contains 80% of the world manganese ore reserves. Mamatwan Mine is hosted within the low grade Mamatwan type ore and is located in the southernmost tip of the KMF. This mine is an open pit mine which is divided into three benches namely the top cut, middle cut and bottom cut. These three benches are structurally controlled by faults which influence the overall grade of the manganese ore. This study is a follow up work to the previous two studies carried out at Wessels Mine and Mamatwan Mine by (Gutzmer and Beukes) in 1995 and 1996 respectively with regards to alteration processes around fault controlled systems in which they concluded that epithermal fluids caused local reduction and bleaching of ore followed by oxidation and carbonate leaching of manganese ore through ascending oxidized groundwater. Metasomatic activity around fault controlled systems is controlled by three main processes namely redistribution, enrichment and depletion. These processes are determined by mobility/immobility of elements from the fault which are introduced into the pre-existing braunite carbonate rich ore. Elements such as Ca, Mg, Si, Fe, C and Mn interact with pre-existing ore due to temperature, fluid pressure, physico-chemical property of fluid gradient. Structurally, faulting and folding contribute to the movement of elements as one end of the system gets depleted the other end of the system gets enriched and vice versa. To better understand this metasomatic activity, it is crucial to conduct mass balance studies of these elements. Grant (1986) introduced the isocon diagram which is a modification of Gresen’s equation (1967) to ascertain which elements are directly or indirectly related to alteration through enrichment and depletion of Ca, Mg, Si, Fe, C and Mn. As the section approaches from altered to less altered manganese ore the mineral chemistry gradually changes from a manganese rich matrix composed of manganomelane and todorokite to a carbonate rich matrix composed of braunite, dolomite, kutnohorite and Mn-rich calcites.
- Full Text:
Minimum dietary diversity scores for women indicate micronutrient adequacy and food insecurity status in South African towns
- Chakona, Gamuchirai, Shackleton, Charlie M
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60930 , vital:27892 , http://dx.doi.org/10.3390/nu9080812
- Description: The lack of dietary diversity is a severe problem experienced by most poor households globally. In particular; women of reproductive age (WRA) are at high risk of inadequate intake of micronutrients resulting from diets dominated by starchy staples. The present study considered the diets, dietary diversity, and food security of women aged 15-49 years along the rural-urban continuum in three South African towns situated along an agro-ecological gradient. A 48 h dietary recall was conducted across two seasons with 554 women from rural, peri-urban, and urban locations of Richards Bay, Dundee, and Harrismith. Minimum Dietary Diversity for WRA (MDD-W) were calculated and a dichotomous indicator based on a set of ten food groups was used to determine if women had consumed at least five food groups the previous 48 h to achieve minimum dietary intake for women. The mean (±sd) MDD-W for Richards Bay (3.78 ± 0.07) was significantly higher than at Dundee (3.21 ± 0.08) and Harrismith (3.36 ± 0.07). Food security and MDD-W were significantly higher in urban locations than in peri-urban or rural ones. There was lower dependence on food purchasing in Richards Bay compared to Dundee and Harrismith. The majority of women in Richards Bay practiced subsistence agriculture, produced a surplus for sale, and collected wild foods which improved dietary intake and food security. The peri-urban populations had limited dietary intake and were more food insecure because of high levels of poverty, unemployment, and lack of land. Peri-urban dwellers are therefore more sensitive to changes in incomes and food prices because they lack safety nets to absorb income or price shocks as they purchase more, rather than growing their own food. This compromises dietary diversity as they have limited access to diverse foods.
- Full Text:
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60930 , vital:27892 , http://dx.doi.org/10.3390/nu9080812
- Description: The lack of dietary diversity is a severe problem experienced by most poor households globally. In particular; women of reproductive age (WRA) are at high risk of inadequate intake of micronutrients resulting from diets dominated by starchy staples. The present study considered the diets, dietary diversity, and food security of women aged 15-49 years along the rural-urban continuum in three South African towns situated along an agro-ecological gradient. A 48 h dietary recall was conducted across two seasons with 554 women from rural, peri-urban, and urban locations of Richards Bay, Dundee, and Harrismith. Minimum Dietary Diversity for WRA (MDD-W) were calculated and a dichotomous indicator based on a set of ten food groups was used to determine if women had consumed at least five food groups the previous 48 h to achieve minimum dietary intake for women. The mean (±sd) MDD-W for Richards Bay (3.78 ± 0.07) was significantly higher than at Dundee (3.21 ± 0.08) and Harrismith (3.36 ± 0.07). Food security and MDD-W were significantly higher in urban locations than in peri-urban or rural ones. There was lower dependence on food purchasing in Richards Bay compared to Dundee and Harrismith. The majority of women in Richards Bay practiced subsistence agriculture, produced a surplus for sale, and collected wild foods which improved dietary intake and food security. The peri-urban populations had limited dietary intake and were more food insecure because of high levels of poverty, unemployment, and lack of land. Peri-urban dwellers are therefore more sensitive to changes in incomes and food prices because they lack safety nets to absorb income or price shocks as they purchase more, rather than growing their own food. This compromises dietary diversity as they have limited access to diverse foods.
- Full Text:
Missing values: a closer look
- Authors: Thorpe, Kerri
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/d1017827 , vital:20798
- Description: Problem: In today’s world, missing values are more present than ever. Due to the ever-changing and fast paced global society in which we live, most business and research data produced around the world contain missing data. This means that locating data which is meticulously precise can be a hard task in itself, but at times may prove essential as the consequences of making use of incomplete data could be disastrous. The reasons for missing data cropping up in almost all forms of work are numerous and shall be discussed in this dissertation. For example, those being interviewed or polled may choose to simply ignore questions which are posed to them, recording equipment may malfunction or be misplaced, or organisers may not be able to locate the respondent in order to rectify the missing data. Whatever the reasons for data being incomplete, it is necessary to avoid having to use inefficient and incomplete data as a result from the above problems. Therefore, various strategies or methods have been developed in order to handle these missing values. It is important, however, that these strategies or methods are utilised effectively as missing data treatment can introduce bias into the analysis. This dissertation shall look at these and other problems in more detail by using a data set which consists of records for 581 children who were interviewed in 1990 as part of the National Longitudinal Survey of Youth (NLSY). Approach: As mentioned above, many strategies or methods have been developed in order to deal with missing values. More specifically, traditional methods such as complete case analysis, available case analysis or single imputation are widely used by researchers and shall be discussed herein. Although these methods are simple and easy to implement, they require assumptions about the data that are not often satisfied in practice. Over the years, more up to date and relevant methods, such as multiple imputation and maximum likelihood have been developed. These methods rely on weaker assumptions and contain superior statistical properties when compared to the traditional techniques. In this dissertation, these traditional methods shall be reviewed and assessed in SAS and shall be compared to the more modern techniques. Results: The ad hoc techniques for handling missing data such as complete case and available case methods produce biased parameter estimates when the data is not missing completely at random (MCAR). Single imputation techniques likewise produce biased estimates as well as result in the underestimation of standard errors. Although the expectation maximisation (EM) algorithm yields unbiased parameter estimates, the lack of convenient standard errors suggests that using this algorithm for hypothesis testing is not a good idea. Multiple imputation, however, yields unbiased parameter estimates and correctly estimates standard errors. Conclusion: Ignoring missing data in any analysis produces biased parameter estimates. Using single imputation to handle missing values is not recommended, as using a single value to replace missing values does not account for the variation that would have been present if the variables were observed. As a result, the variance will be greatly underestimated. The more modern missing data methods such as the EM algorithm and multiple imputation are preferred over the traditional techniques as they require less stringent assumptions and they also mitigate the downsides of the older methods.
- Full Text:
- Authors: Thorpe, Kerri
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/d1017827 , vital:20798
- Description: Problem: In today’s world, missing values are more present than ever. Due to the ever-changing and fast paced global society in which we live, most business and research data produced around the world contain missing data. This means that locating data which is meticulously precise can be a hard task in itself, but at times may prove essential as the consequences of making use of incomplete data could be disastrous. The reasons for missing data cropping up in almost all forms of work are numerous and shall be discussed in this dissertation. For example, those being interviewed or polled may choose to simply ignore questions which are posed to them, recording equipment may malfunction or be misplaced, or organisers may not be able to locate the respondent in order to rectify the missing data. Whatever the reasons for data being incomplete, it is necessary to avoid having to use inefficient and incomplete data as a result from the above problems. Therefore, various strategies or methods have been developed in order to handle these missing values. It is important, however, that these strategies or methods are utilised effectively as missing data treatment can introduce bias into the analysis. This dissertation shall look at these and other problems in more detail by using a data set which consists of records for 581 children who were interviewed in 1990 as part of the National Longitudinal Survey of Youth (NLSY). Approach: As mentioned above, many strategies or methods have been developed in order to deal with missing values. More specifically, traditional methods such as complete case analysis, available case analysis or single imputation are widely used by researchers and shall be discussed herein. Although these methods are simple and easy to implement, they require assumptions about the data that are not often satisfied in practice. Over the years, more up to date and relevant methods, such as multiple imputation and maximum likelihood have been developed. These methods rely on weaker assumptions and contain superior statistical properties when compared to the traditional techniques. In this dissertation, these traditional methods shall be reviewed and assessed in SAS and shall be compared to the more modern techniques. Results: The ad hoc techniques for handling missing data such as complete case and available case methods produce biased parameter estimates when the data is not missing completely at random (MCAR). Single imputation techniques likewise produce biased estimates as well as result in the underestimation of standard errors. Although the expectation maximisation (EM) algorithm yields unbiased parameter estimates, the lack of convenient standard errors suggests that using this algorithm for hypothesis testing is not a good idea. Multiple imputation, however, yields unbiased parameter estimates and correctly estimates standard errors. Conclusion: Ignoring missing data in any analysis produces biased parameter estimates. Using single imputation to handle missing values is not recommended, as using a single value to replace missing values does not account for the variation that would have been present if the variables were observed. As a result, the variance will be greatly underestimated. The more modern missing data methods such as the EM algorithm and multiple imputation are preferred over the traditional techniques as they require less stringent assumptions and they also mitigate the downsides of the older methods.
- Full Text:
Modelling dialectical processes in environmental learning
- Authors: Schudel, Ingrid J
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/294409 , vital:57219 , xlink:href="https://doi.org/10.1080/14767430.2017.1288061"
- Description: This paper describes a critical realist intensive case study, which develops and tests a ‘dialectic process model of transformative learning’. The model is inspired by Bhaskar's (1993) onto-axiological chain (or MELD Schema) as outlined in his formulation of dialectical critical realism. The study describes transformative environmental learning processes focusing on food security in two primary schools in rural South Africa. The model elaborates on the four links in the onto-axiological chain by describing four knowledge interests across the two cases: knowledge of ‘what is and what is not’, knowledge of ‘what could be’, knowledge of ‘what should be’, and knowledge of ‘what can be’. The model also highlights the emergent nature of epistemic relations in transformative learning processes. The paper discusses the model in relation to a transformative, open-ended and context specific approach to Environmental Education (EE)/ESD. The paper illustrates that Bhaskar’s MELD is a robust schema for investigating learning-led change in EE and suggests its relevance in other research contexts concerned with societal transformation.
- Full Text:
- Authors: Schudel, Ingrid J
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/294409 , vital:57219 , xlink:href="https://doi.org/10.1080/14767430.2017.1288061"
- Description: This paper describes a critical realist intensive case study, which develops and tests a ‘dialectic process model of transformative learning’. The model is inspired by Bhaskar's (1993) onto-axiological chain (or MELD Schema) as outlined in his formulation of dialectical critical realism. The study describes transformative environmental learning processes focusing on food security in two primary schools in rural South Africa. The model elaborates on the four links in the onto-axiological chain by describing four knowledge interests across the two cases: knowledge of ‘what is and what is not’, knowledge of ‘what could be’, knowledge of ‘what should be’, and knowledge of ‘what can be’. The model also highlights the emergent nature of epistemic relations in transformative learning processes. The paper discusses the model in relation to a transformative, open-ended and context specific approach to Environmental Education (EE)/ESD. The paper illustrates that Bhaskar’s MELD is a robust schema for investigating learning-led change in EE and suggests its relevance in other research contexts concerned with societal transformation.
- Full Text:
Modelling the causality between FDI and Zimbabwe’s economic growth
- Authors: Mashamhanda, Tendai
- Date: 2017
- Subjects: Investments, Foreign -- Zimbabwe , Zimbabwe -- Economic conditions -- 1965-1980 , Zimbabwe -- Economic conditions -- 1980-
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/50260 , vital:25970
- Description: The study investigates the causal nexus between economic growth and FDI in Zimbabwe for the period spanning 1976 to 2011. The bounds testing approach to cointegration and Granger causality methodology was applied and results suggest a bi-directional causal relationship between FDI and economic growth in the long run. However, the causal effect from economic growth to FDI was weak. Domestic investment, human capital and trade openness were also found to be crucial determinants of economic growth in Zimbabwe. Implementing policies that promote inflow of FDI into Zimbabwe are recommended.
- Full Text:
- Authors: Mashamhanda, Tendai
- Date: 2017
- Subjects: Investments, Foreign -- Zimbabwe , Zimbabwe -- Economic conditions -- 1965-1980 , Zimbabwe -- Economic conditions -- 1980-
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/50260 , vital:25970
- Description: The study investigates the causal nexus between economic growth and FDI in Zimbabwe for the period spanning 1976 to 2011. The bounds testing approach to cointegration and Granger causality methodology was applied and results suggest a bi-directional causal relationship between FDI and economic growth in the long run. However, the causal effect from economic growth to FDI was weak. Domestic investment, human capital and trade openness were also found to be crucial determinants of economic growth in Zimbabwe. Implementing policies that promote inflow of FDI into Zimbabwe are recommended.
- Full Text:
Modelling water quality : complexity versus simplicity
- Authors: Jacobs, Haden
- Date: 2017
- Subjects: Water quality management -- Mathematical models , Water quality -- Measurement , Water quality biological assessment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4754 , vital:20721
- Description: Water quality management makes use of water quality models as decision making tools. Water quality management decisions need to be informed by information that is as reliable as possible. There are many situations where observational data are limited and therefore models or simulation methods have a significant role to play in providing some information that can be used to guide management decisions. Water quality modelling is the use of mathematical equations and statistics to represent the processes affecting water quality in the natural environment. Water quality data are expensive and difficult to obtain. Nutrient sampling requires a technician to obtain ‘grab samples’ which need to be kept at low temperatures and analysed in a laboratory. The laboratory analyses of nutrients is expensive and time consuming. The data required by water quality models are seldom available as complete datasets of sufficient length. This is especially true for ungauged regions, either in small rural catchments or even major rivers in developing countries. Water quality modelling requires simulated or observed water quantity data as water quality is affected by water quantity. Both the water quality modelling and water quantity modelling require data to simulate the required processes. Data are necessary for both model structure as well as model set up for calibration and validation. This study aimed to investigate the simulation of water quality in a low order stream with limited observed data using a relatively complex as well as a much simpler water quality model, represented by QUAL2K and an in-house developed Mass Balance Nutrient (MBN) model, respectively. The two models differ greatly in the approach adopted for water quality modelling, with QUAL2K being an instream water quality fate model and the MBN model being a catchment scale model that links water quantity and quality. The MBN model uses hydrological routines to simulate those components of the hydrological cycle that are expected to differ with respect to their water quality signatures (low flows, high flows, etc.). Incremental flows are broken down into flow fractions, and nutrient signatures are assigned to fractions to represent catchment nutrient load input. A linear regression linked to an urban runoff model was used to simulate water quality entering the river system from failing municipal infrastructure, which was found to be a highly variable source of nutrients within the system. A simple algal model was adapted from CE-QUAL-W2 to simulate nutrient assimilation by benthic algae. QUAL2K, an instream water quality fate model, proved unsuitable for modelling diffuse sources for a wide range of conditions and was data intensive when compared to the data requirements of the MBN model. QUAL2K did not simulate water quality accurately over a wide range of flow conditions and was found to be more suitable to simulating point sources. The MBN model did not provide accurate results in terms of the simulation of individual daily water quality values; however, the general trends and frequency characteristics of the simulations were satisfactory. Despite some uncertainties, the MBN model remains useful for extending data for catchments with limited observed water quality data. The MBN model was found to be more suitable for South African conditions than QUAL2K, given the data requirements of each model and water quality and flow data available from the Department of Water and Sanitation. The MBN model was found to be particularly useful by providing frequency distributions of water quality loads or concentrations using minimal data that can be related to the risks of exceeding management thresholds.
- Full Text:
- Authors: Jacobs, Haden
- Date: 2017
- Subjects: Water quality management -- Mathematical models , Water quality -- Measurement , Water quality biological assessment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4754 , vital:20721
- Description: Water quality management makes use of water quality models as decision making tools. Water quality management decisions need to be informed by information that is as reliable as possible. There are many situations where observational data are limited and therefore models or simulation methods have a significant role to play in providing some information that can be used to guide management decisions. Water quality modelling is the use of mathematical equations and statistics to represent the processes affecting water quality in the natural environment. Water quality data are expensive and difficult to obtain. Nutrient sampling requires a technician to obtain ‘grab samples’ which need to be kept at low temperatures and analysed in a laboratory. The laboratory analyses of nutrients is expensive and time consuming. The data required by water quality models are seldom available as complete datasets of sufficient length. This is especially true for ungauged regions, either in small rural catchments or even major rivers in developing countries. Water quality modelling requires simulated or observed water quantity data as water quality is affected by water quantity. Both the water quality modelling and water quantity modelling require data to simulate the required processes. Data are necessary for both model structure as well as model set up for calibration and validation. This study aimed to investigate the simulation of water quality in a low order stream with limited observed data using a relatively complex as well as a much simpler water quality model, represented by QUAL2K and an in-house developed Mass Balance Nutrient (MBN) model, respectively. The two models differ greatly in the approach adopted for water quality modelling, with QUAL2K being an instream water quality fate model and the MBN model being a catchment scale model that links water quantity and quality. The MBN model uses hydrological routines to simulate those components of the hydrological cycle that are expected to differ with respect to their water quality signatures (low flows, high flows, etc.). Incremental flows are broken down into flow fractions, and nutrient signatures are assigned to fractions to represent catchment nutrient load input. A linear regression linked to an urban runoff model was used to simulate water quality entering the river system from failing municipal infrastructure, which was found to be a highly variable source of nutrients within the system. A simple algal model was adapted from CE-QUAL-W2 to simulate nutrient assimilation by benthic algae. QUAL2K, an instream water quality fate model, proved unsuitable for modelling diffuse sources for a wide range of conditions and was data intensive when compared to the data requirements of the MBN model. QUAL2K did not simulate water quality accurately over a wide range of flow conditions and was found to be more suitable to simulating point sources. The MBN model did not provide accurate results in terms of the simulation of individual daily water quality values; however, the general trends and frequency characteristics of the simulations were satisfactory. Despite some uncertainties, the MBN model remains useful for extending data for catchments with limited observed water quality data. The MBN model was found to be more suitable for South African conditions than QUAL2K, given the data requirements of each model and water quality and flow data available from the Department of Water and Sanitation. The MBN model was found to be particularly useful by providing frequency distributions of water quality loads or concentrations using minimal data that can be related to the risks of exceeding management thresholds.
- Full Text:
Modern celebrity and inspiration in South Africa: an examination of the Mail & Guardian 200 Young South Africans
- Authors: Lishivha, Welcome
- Date: 2017
- Subjects: Youth in mass media -- South Africa , Youth -- Social conditions -- South Africa , Mail & Guardian , Mail & Guardian 200 Young South Africans
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/5165 , vital:20782
- Description: The postapartheid condition of a majority of young people in South Africa is substantially similar to the apartheid conditions under which their parents lived. This results in a dominant narrative in the media and everyday talk circulating in South African that the youth are a ‘lost generation’ and also that they represent a significant danger and risk for the stability of our democracy. Against this backdrop The Mail and Guardian, one of the South Africa’s most influential newspapers has chosen to celebrate a small number of young people every year as inspirational and extraordinary in their achievements. This investigation into this representation of a significant - although small - group of young South Africans employed content analysis of the 2015 edition of 200 Young South Africans, interviews with profiled individuals across the years, and a focus group of readers. The study aimed to unpack the complexity of constructing certain young people as exemplary given the structural conditions that constrain and prevent a majority from attaining the education and mobility they need to make a difference in their own lives. The study found through the content analysis that the Mail&Guardian is setting up these young people as exemplary citizens whose actions should inspire other young people to similarly ‘make a difference’. Through the interviews the study found that those featured on the list found both that there was significant social capital in being valorised this way, but that this position was also a complex one to negotiate given the structural limitations of poverty and lack of education for those out of whom they had been chosen. The readers in the focus group did find inspiration in reading about their exemplary peers but they too were conscious of how small a group this was in comparison to the majority of young South Africans. In conclusion the study found that the narrative of hope, inspiration and making a difference is an important message in relation to a generalised hopelessness about South African youth but that it runs the risk of ignoring the significant structural constraints that young, poor, undereducated, unskilled young South Africans face.
- Full Text:
- Authors: Lishivha, Welcome
- Date: 2017
- Subjects: Youth in mass media -- South Africa , Youth -- Social conditions -- South Africa , Mail & Guardian , Mail & Guardian 200 Young South Africans
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/5165 , vital:20782
- Description: The postapartheid condition of a majority of young people in South Africa is substantially similar to the apartheid conditions under which their parents lived. This results in a dominant narrative in the media and everyday talk circulating in South African that the youth are a ‘lost generation’ and also that they represent a significant danger and risk for the stability of our democracy. Against this backdrop The Mail and Guardian, one of the South Africa’s most influential newspapers has chosen to celebrate a small number of young people every year as inspirational and extraordinary in their achievements. This investigation into this representation of a significant - although small - group of young South Africans employed content analysis of the 2015 edition of 200 Young South Africans, interviews with profiled individuals across the years, and a focus group of readers. The study aimed to unpack the complexity of constructing certain young people as exemplary given the structural conditions that constrain and prevent a majority from attaining the education and mobility they need to make a difference in their own lives. The study found through the content analysis that the Mail&Guardian is setting up these young people as exemplary citizens whose actions should inspire other young people to similarly ‘make a difference’. Through the interviews the study found that those featured on the list found both that there was significant social capital in being valorised this way, but that this position was also a complex one to negotiate given the structural limitations of poverty and lack of education for those out of whom they had been chosen. The readers in the focus group did find inspiration in reading about their exemplary peers but they too were conscious of how small a group this was in comparison to the majority of young South Africans. In conclusion the study found that the narrative of hope, inspiration and making a difference is an important message in relation to a generalised hopelessness about South African youth but that it runs the risk of ignoring the significant structural constraints that young, poor, undereducated, unskilled young South Africans face.
- Full Text:
Molecular cloning and expression of equine CYP1A2 in Escherichia coli
- Authors: Mkabayi, Lithalethu
- Date: 2017
- Subjects: Escherichia coli , Escherichia coli infections in animals , Cytochrome P-450 , Cytochromes , Horses -- Effect of drugs on
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4830 , vital:20734
- Description: Information regarding drug metabolism in veterinary species, especially horses, remains fragmented and incomplete. This information is essential for detection of metabolites of potential performance-enhancing substances in horseracing and for veterinary drug development. Equine liver microsomes have been used to study metabolism of a limited number of drugs, but these provide little information about individual drug metabolizing enzymes. Recombinant CYP enzyme systems are commonly used to determine contribution of individual CYP to metabolism of specific drugs. A limited number of recombinant equine CYPs have been expressed in insect cells and mammalian cell lines. However, there are no reports of recombinant equine CYP1A2 enzyme. In this study, equine CYP1A2 was identified, codon-optimized, cloned and expressed in E. coli BL21 cells. Multiple sequence alignments of equine CYP1A2 revealed an amino acid sequence identity of 83.69% to its human homolog which has previously been expressed in E. coli. The enzyme was expressed using both auto-induction and IPTG induction. Expressed equine CYP1A2 had a size of about 55 kDa, and was insoluble after cell lysis. Sarkosyl- solubilized CYP1A2 was purified using nickel affinity chromatography and gel filtration. For activity reconstitution, yeast NADPH-cytochrome P450 reductase was first expressed in E. coli BL21 cells and exhibited activity of 0.13 U/ml. Activity assay with Glo-P450 CYP1A2 assay kit indicated that CYP1A2 was inactive. Despite numerous attempts to obtain the activity, the CYP1A2 remained inactive. Although expression of equine CYP1A2 in E. coli produced non- catalytically active enzyme, this study could be used as the first step in an effort to fully develop a recombinant equine CYP1A2 system.
- Full Text:
- Authors: Mkabayi, Lithalethu
- Date: 2017
- Subjects: Escherichia coli , Escherichia coli infections in animals , Cytochrome P-450 , Cytochromes , Horses -- Effect of drugs on
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4830 , vital:20734
- Description: Information regarding drug metabolism in veterinary species, especially horses, remains fragmented and incomplete. This information is essential for detection of metabolites of potential performance-enhancing substances in horseracing and for veterinary drug development. Equine liver microsomes have been used to study metabolism of a limited number of drugs, but these provide little information about individual drug metabolizing enzymes. Recombinant CYP enzyme systems are commonly used to determine contribution of individual CYP to metabolism of specific drugs. A limited number of recombinant equine CYPs have been expressed in insect cells and mammalian cell lines. However, there are no reports of recombinant equine CYP1A2 enzyme. In this study, equine CYP1A2 was identified, codon-optimized, cloned and expressed in E. coli BL21 cells. Multiple sequence alignments of equine CYP1A2 revealed an amino acid sequence identity of 83.69% to its human homolog which has previously been expressed in E. coli. The enzyme was expressed using both auto-induction and IPTG induction. Expressed equine CYP1A2 had a size of about 55 kDa, and was insoluble after cell lysis. Sarkosyl- solubilized CYP1A2 was purified using nickel affinity chromatography and gel filtration. For activity reconstitution, yeast NADPH-cytochrome P450 reductase was first expressed in E. coli BL21 cells and exhibited activity of 0.13 U/ml. Activity assay with Glo-P450 CYP1A2 assay kit indicated that CYP1A2 was inactive. Despite numerous attempts to obtain the activity, the CYP1A2 remained inactive. Although expression of equine CYP1A2 in E. coli produced non- catalytically active enzyme, this study could be used as the first step in an effort to fully develop a recombinant equine CYP1A2 system.
- Full Text:
Monolingualism and its meaning in two KwaZulu-Natal high schools
- Authors: Carlyle, Jacqui
- Date: 2017
- Subjects: Monolingualism -- South Africa , Monolingualism -- South Africa -- Case studies , Language awareness -- South Africa , Language and education -- South Africa , School children -- South Africa -- Attitudes , School children -- South Africa -- Attitudes -- Case studies , African languages -- Study and teaching -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6543 , vital:21135
- Description: This study reports on the identity and attitudes of monolingual English speakers (MES) at two high schools in Durban, South Africa, in relation particularly to the role and meaning of monolingualism. Two bodies of data are used to investigate the attitudes of MES and are oriented towards four variables: English, African languages (particularly Zulu), monolingualism and plurilingualism. The attitudes to these variables reveal the impact on identity of language usage in Durban, and negotiations of the participants in trying to mitigate or justify attitudes that are counter to the embracing of diversity encouraged in modern South Africa. First, an attitude questionnaire provides quantitative data that is subjected to analysis, including a chi-squared test. Second, a narrative elicitation interview provides qualitative narrative data that is analysed in relation to APPRAISAL theory. Both analysis types are used to ascertain the presence of a monolingual mindset in the scholars’ responses, as well as to capture the ideological forces to which they are subjected as monolingual English speakers in the unique multilingual setting of Durban. In essence, the data points to a discourse of compromise and unease on the part of the participants - as they juggle with the effects of an English-centric monolingual mindset, and a more pervasive pluralism that embraces the Rainbowism of ‘the new South Africa’. This discourse of compromise is characterized on one side by insecurity and dissatisfaction with the language in education policy, and well as the monolingual upbringing of MES in Durban, and a lack of Language other than English (LOTE), in particular, Zulu. This side of the compromise also portrays a pro- plurilingual orientation, a positive valuation of knowing a LOTE and of plurilingual people. Here, however, the manifestation of the ‘other side’ of the compromise appears as the MES characterize plurilingualism as exceptional and too difficult, and language learning at school as having a negative impact on academic success. Alongside this is a normalization of English and othering of African languages in practical situation. English is also promoted as the language of unity and economic and academic progress or success, while the material value of African languages is questioned.
- Full Text:
- Authors: Carlyle, Jacqui
- Date: 2017
- Subjects: Monolingualism -- South Africa , Monolingualism -- South Africa -- Case studies , Language awareness -- South Africa , Language and education -- South Africa , School children -- South Africa -- Attitudes , School children -- South Africa -- Attitudes -- Case studies , African languages -- Study and teaching -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6543 , vital:21135
- Description: This study reports on the identity and attitudes of monolingual English speakers (MES) at two high schools in Durban, South Africa, in relation particularly to the role and meaning of monolingualism. Two bodies of data are used to investigate the attitudes of MES and are oriented towards four variables: English, African languages (particularly Zulu), monolingualism and plurilingualism. The attitudes to these variables reveal the impact on identity of language usage in Durban, and negotiations of the participants in trying to mitigate or justify attitudes that are counter to the embracing of diversity encouraged in modern South Africa. First, an attitude questionnaire provides quantitative data that is subjected to analysis, including a chi-squared test. Second, a narrative elicitation interview provides qualitative narrative data that is analysed in relation to APPRAISAL theory. Both analysis types are used to ascertain the presence of a monolingual mindset in the scholars’ responses, as well as to capture the ideological forces to which they are subjected as monolingual English speakers in the unique multilingual setting of Durban. In essence, the data points to a discourse of compromise and unease on the part of the participants - as they juggle with the effects of an English-centric monolingual mindset, and a more pervasive pluralism that embraces the Rainbowism of ‘the new South Africa’. This discourse of compromise is characterized on one side by insecurity and dissatisfaction with the language in education policy, and well as the monolingual upbringing of MES in Durban, and a lack of Language other than English (LOTE), in particular, Zulu. This side of the compromise also portrays a pro- plurilingual orientation, a positive valuation of knowing a LOTE and of plurilingual people. Here, however, the manifestation of the ‘other side’ of the compromise appears as the MES characterize plurilingualism as exceptional and too difficult, and language learning at school as having a negative impact on academic success. Alongside this is a normalization of English and othering of African languages in practical situation. English is also promoted as the language of unity and economic and academic progress or success, while the material value of African languages is questioned.
- Full Text:
More is not necessarily better: the interaction between insect population density and culture age of fungus on the control of invasive weed water hyacinth
- Authors: Ray, Puja , Hill, Martin P
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424777 , vital:72183 , xlink:href="https://doi.org/10.1007/s10750-015-2454-3"
- Description: The possibilities of a positive or negative impact the biocontrol agents may have on each other as well as on the control of the weed itself, inspired us to study the interactions between the mirid, Eccritotarsus catarinensis and the phytopathogen, Acremonium zonatum, biocontrol agents of water hyacinth, Eichhornia crassipes. Observations were made on disease initiation time of A. zonatum grown for different time durations with different insect densities on water hyacinth. In absence of mirids, the lowest (3.1 days) and the highest (5.1 days) disease initiation time was observed using 21 and 42 days old culture respectively. In treatments involving mirids, the shortest (1.78 days) and the longest (13.22 days) disease initiation time by A. zonatum was observed on water hyacinth with 10 and 20 mirids/plant respectively. By the 30th day, maximum percentage damage (77.9%) was observed in the treatment of 21 day old fungal culture with 20 mirid density/plant despite of initial delay in disease initiation. This result suggests an initial development of a plant defense response due to mirid feeding delaying the pathogen from establishing. Extensive studies involving multitrophic interactions should be an essential part of pre-release assessments to enhance the success rates of biological control of weeds.
- Full Text:
- Authors: Ray, Puja , Hill, Martin P
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/424777 , vital:72183 , xlink:href="https://doi.org/10.1007/s10750-015-2454-3"
- Description: The possibilities of a positive or negative impact the biocontrol agents may have on each other as well as on the control of the weed itself, inspired us to study the interactions between the mirid, Eccritotarsus catarinensis and the phytopathogen, Acremonium zonatum, biocontrol agents of water hyacinth, Eichhornia crassipes. Observations were made on disease initiation time of A. zonatum grown for different time durations with different insect densities on water hyacinth. In absence of mirids, the lowest (3.1 days) and the highest (5.1 days) disease initiation time was observed using 21 and 42 days old culture respectively. In treatments involving mirids, the shortest (1.78 days) and the longest (13.22 days) disease initiation time by A. zonatum was observed on water hyacinth with 10 and 20 mirids/plant respectively. By the 30th day, maximum percentage damage (77.9%) was observed in the treatment of 21 day old fungal culture with 20 mirid density/plant despite of initial delay in disease initiation. This result suggests an initial development of a plant defense response due to mirid feeding delaying the pathogen from establishing. Extensive studies involving multitrophic interactions should be an essential part of pre-release assessments to enhance the success rates of biological control of weeds.
- Full Text:
Morphological awareness in readers of IsiXhosa
- Authors: Rees, Siân Angharad
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4569 , vital:20694
- Description: This study focuses particularly on the development of four Morphological Awareness reading tests in isiXhosa and on the relationship of Morphological Awareness to reading success among 74 Grade 3 isiXhosa-speaking foundation-phase learners from three peri-urban schools. It explores in-depth why not all previously established Morphological Awareness tests for other languages suit the morphology of isiXhosa and how these tests have been revised in order to do so. Conventionally, the focus of Morphological Awareness literature has been on derivational morphology and reading comprehension. This study did not find significant correlations with comprehension, but rather with the children's ability to decode. Fluency and Morphological Awareness have not been given as much attention in the literature, but Morphological Awareness could be important for processing the agglutinating structure of the language in reading. This study also argues that it is not a specific awareness of derivational morphology over inflectional morphology, but rather a general awareness of one's language structure that is more important at this stage in their literacy development; specifically a general awareness of prefixes and suffixes. In addition, it was found that an explicit awareness of the morphological structure of the language related more to fluency and tests that accessed an innate and implicit Morphological Awareness had the strongest correlations overall with comprehension. The findings from this report have implications regarding how future curriculum developments for morphologically rich languages like isiXhosa should be approached. The positive and practical implications of including different types of Morphological Awareness tutoring in curricula is argued for, especially when teaching younger readers how to approach morphologically complex words in texts.
- Full Text:
- Authors: Rees, Siân Angharad
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4569 , vital:20694
- Description: This study focuses particularly on the development of four Morphological Awareness reading tests in isiXhosa and on the relationship of Morphological Awareness to reading success among 74 Grade 3 isiXhosa-speaking foundation-phase learners from three peri-urban schools. It explores in-depth why not all previously established Morphological Awareness tests for other languages suit the morphology of isiXhosa and how these tests have been revised in order to do so. Conventionally, the focus of Morphological Awareness literature has been on derivational morphology and reading comprehension. This study did not find significant correlations with comprehension, but rather with the children's ability to decode. Fluency and Morphological Awareness have not been given as much attention in the literature, but Morphological Awareness could be important for processing the agglutinating structure of the language in reading. This study also argues that it is not a specific awareness of derivational morphology over inflectional morphology, but rather a general awareness of one's language structure that is more important at this stage in their literacy development; specifically a general awareness of prefixes and suffixes. In addition, it was found that an explicit awareness of the morphological structure of the language related more to fluency and tests that accessed an innate and implicit Morphological Awareness had the strongest correlations overall with comprehension. The findings from this report have implications regarding how future curriculum developments for morphologically rich languages like isiXhosa should be approached. The positive and practical implications of including different types of Morphological Awareness tutoring in curricula is argued for, especially when teaching younger readers how to approach morphologically complex words in texts.
- Full Text:
Motives behind the implementation of renewable energy sources in South African businesses
- Authors: Smith, Brendon Michael
- Date: 2017
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/7667 , vital:21283
- Description: There are numerous advantages and disadvantages for companies to implement renewable energy in South Africa. The motives (drivers or challenges) behind the decision to implement renewable energy resources or not is what this research will be addressing. Economic and environmental motives were the major motives behind implementing renewable energy sources in literature. The main objective for this research was to identify and describe the motives and challenges of implementing renewable energy sources in SA businesses, aligning these with sustainability pillars. The data collection method that was used in this research was documentation analysis and questionnaires. The companies that were chosen for this research were sampled from Kwa-Zulu Natal. Results showed that economic motives were the main decisions for companies implementing renewable energy or not, although there were also significant environmental and social motives that businesses need to consider. This research has provided an understanding of the motives that can have a positive or negative impact on companies who want to install renewable energy for their business.
- Full Text:
- Authors: Smith, Brendon Michael
- Date: 2017
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/7667 , vital:21283
- Description: There are numerous advantages and disadvantages for companies to implement renewable energy in South Africa. The motives (drivers or challenges) behind the decision to implement renewable energy resources or not is what this research will be addressing. Economic and environmental motives were the major motives behind implementing renewable energy sources in literature. The main objective for this research was to identify and describe the motives and challenges of implementing renewable energy sources in SA businesses, aligning these with sustainability pillars. The data collection method that was used in this research was documentation analysis and questionnaires. The companies that were chosen for this research were sampled from Kwa-Zulu Natal. Results showed that economic motives were the main decisions for companies implementing renewable energy or not, although there were also significant environmental and social motives that businesses need to consider. This research has provided an understanding of the motives that can have a positive or negative impact on companies who want to install renewable energy for their business.
- Full Text:
Multilingualism and intercultural communication: a South African perspective
- Kaschula, Russell H, Maseko, Pamela, Wolff, H Ekkehard
- Authors: Kaschula, Russell H , Maseko, Pamela , Wolff, H Ekkehard
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67015 , vital:29019 , ISBN 9781776140275 , https://muse.jhu.edu/book/52741
- Description: publisher version , To date, there has been no published textbook which takes into account changing sociolinguistic dynamics that have influenced South African society. Multilingualism and Intercultural Communication breaks new ground in this arena. Its scope ranges from macro-sociolinguistic questions pertaining to language policies and their implementation (or non-implementation), to micro-sociolinguistic observations of actual language-use in verbal interaction, mainly in multilingual contexts of Higher Education (HE). There is a gradual move for the study of language and culture to be taught in the context of (professional) disciplines in which they would be used, such as Journalism and African languages, Education and African languages, etc. The book caters for this growing market. Because of its multilingual nature, it caters to English and Afrikaans language speakers, as well as the Sotho and Nguni language groups. It brings together various inter-linked disciplines such as Sociolinguistics and Applied Language Studies, Media Studies and Journalism, History and Education, Social and Natural Sciences, Law, Human Language Technology, Music, Intercultural Communication and Literary Studies. The unique cross-cutting disciplinary features of the book will make it a must-have for twenty-first century South African students and scholars and those interested in applied language issues.
- Full Text: false
- Authors: Kaschula, Russell H , Maseko, Pamela , Wolff, H Ekkehard
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67015 , vital:29019 , ISBN 9781776140275 , https://muse.jhu.edu/book/52741
- Description: publisher version , To date, there has been no published textbook which takes into account changing sociolinguistic dynamics that have influenced South African society. Multilingualism and Intercultural Communication breaks new ground in this arena. Its scope ranges from macro-sociolinguistic questions pertaining to language policies and their implementation (or non-implementation), to micro-sociolinguistic observations of actual language-use in verbal interaction, mainly in multilingual contexts of Higher Education (HE). There is a gradual move for the study of language and culture to be taught in the context of (professional) disciplines in which they would be used, such as Journalism and African languages, Education and African languages, etc. The book caters for this growing market. Because of its multilingual nature, it caters to English and Afrikaans language speakers, as well as the Sotho and Nguni language groups. It brings together various inter-linked disciplines such as Sociolinguistics and Applied Language Studies, Media Studies and Journalism, History and Education, Social and Natural Sciences, Law, Human Language Technology, Music, Intercultural Communication and Literary Studies. The unique cross-cutting disciplinary features of the book will make it a must-have for twenty-first century South African students and scholars and those interested in applied language issues.
- Full Text: false
Multiple drivers of local (non-) compliance in community-based marine resource management: Case studies from the South Pacific
- Rohe, Janne R, Aswani, Shankar, Schlüter, Achim, Ferse, Sebastian
- Authors: Rohe, Janne R , Aswani, Shankar , Schlüter, Achim , Ferse, Sebastian
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420445 , vital:71744 , xlink:href="https://doi.org/10.3389/fmars.2017.00172"
- Description: The outcomes of marine conservation and related management interventions depend to a large extent on people's compliance with these rule systems. In the South Pacific, community-based marine resource management (CBMRM) has gained wide recognition as a strategy for the sustainable management of marine resources. In current practice, CBMRM initiatives often build upon customary forms of marine governance, integrating scientific advice and management principles in collaboration with external partners. However, diverse socio-economic developments as well as limited legal mandates can challenge these approaches. Compliance with and effective (legally-backed) enforcement of local management strategies constitute a growing challenge for communities—often resulting in considerable impact on the success or failure of CBMRM. Marine management arrangements are highly dynamic over time, and similarly compliance with rule systems tends to change depending on context. Understanding the factors contributing to (non-) compliance in a given setting is key to the design and function of adaptive management approaches. Yet, few empirical studies have looked in depth into the dynamics around local (non-) compliance with local marine tenure rules under the transforming management arrangements. Using two case studies from Solomon Islands and Fiji, we investigate what drives local (non-) compliance with CBMRM and what hinders or supports its effective enforcement. The case studies reveal that non-compliance is mainly driven by: (1) diminishing perceived legitimacy of local rules and rule-makers; (2) increased incentives to break rules due to market access and/ or lack of alternative income; and (3) relatively weak enforcement of local rules (i.e., low perceptions of risk from sanctions for rule-breaking). These drivers do not stand alone but can act together and add up to impair effective management. We further analyze how enforcement of CBMRM is challenged through a range of institutional; socio-cultural and technical/financial constraints, which are in parts a result of the dynamism and ongoing transformations of management arrangements. Our study underlines the importance of better understanding and contextualizing marine resource management processes under dynamic conditions for an improved understanding of compliance in a particular setting.
- Full Text:
- Authors: Rohe, Janne R , Aswani, Shankar , Schlüter, Achim , Ferse, Sebastian
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420445 , vital:71744 , xlink:href="https://doi.org/10.3389/fmars.2017.00172"
- Description: The outcomes of marine conservation and related management interventions depend to a large extent on people's compliance with these rule systems. In the South Pacific, community-based marine resource management (CBMRM) has gained wide recognition as a strategy for the sustainable management of marine resources. In current practice, CBMRM initiatives often build upon customary forms of marine governance, integrating scientific advice and management principles in collaboration with external partners. However, diverse socio-economic developments as well as limited legal mandates can challenge these approaches. Compliance with and effective (legally-backed) enforcement of local management strategies constitute a growing challenge for communities—often resulting in considerable impact on the success or failure of CBMRM. Marine management arrangements are highly dynamic over time, and similarly compliance with rule systems tends to change depending on context. Understanding the factors contributing to (non-) compliance in a given setting is key to the design and function of adaptive management approaches. Yet, few empirical studies have looked in depth into the dynamics around local (non-) compliance with local marine tenure rules under the transforming management arrangements. Using two case studies from Solomon Islands and Fiji, we investigate what drives local (non-) compliance with CBMRM and what hinders or supports its effective enforcement. The case studies reveal that non-compliance is mainly driven by: (1) diminishing perceived legitimacy of local rules and rule-makers; (2) increased incentives to break rules due to market access and/ or lack of alternative income; and (3) relatively weak enforcement of local rules (i.e., low perceptions of risk from sanctions for rule-breaking). These drivers do not stand alone but can act together and add up to impair effective management. We further analyze how enforcement of CBMRM is challenged through a range of institutional; socio-cultural and technical/financial constraints, which are in parts a result of the dynamism and ongoing transformations of management arrangements. Our study underlines the importance of better understanding and contextualizing marine resource management processes under dynamic conditions for an improved understanding of compliance in a particular setting.
- Full Text:
My Friend, the stranger: Somali spaza shop operators in the villages around Cofimvaba, Eastern Cape, South Africa
- Authors: Maselwa, Avuyile
- Date: 2017
- Subjects: Immigrant business enterprises -- South Africa -- Eastern Cape , Somalis -- South Africa -- Eastern Cape , Somalis -- South Africa -- Eastern Cape -- Public opinion , Somalis -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/41738 , vital:25127
- Description: This thesis presents a study of the relationships between Somali spaza operators and the villagers living in the villages around Cofimvaba. The Somali spaza operators are operating spazas in the villages around Cofimvaba in the Intsika Yethu District Municipality (IYDM) located in the Chris Hani District Municipality (CHDM). Spaza shops are general dealers selling daily consumption items, which usually operate in the informal sector, primarily in poorer black neighbourhoods, both urban and rural. Resentment of the very visible, post-apartheid, expansion of immigrant entrepreneurship - in the informal sector, notably in spazas- has been central to South African anti-immigrant sentiment, popularly dubbed “xenophobia,” which casts foreigners, mainly black or Asian, as stealing South African resources. Foreign spaza operators, many of them Somalis, have been subject to ongoing violence and looting for well over a decade, notably in the Eastern Cape and Western Cape provinces. Yet in the deeply impoverished villages around Cofimvaba, in the former Transkei black homeland in the Eastern Cape, where Somalis play a central and growing role in spazas, such attacks are unknown. The aim of this thesis is to understand why. Careful qualitative research in several villages has indicated key reasons. These include the relative absence of South African, locally- owned spazas, and so, the lack of a local group driving xenophobic resentment; the convenience offered by Somali-owned spazas in these isolated villages, the affordability of the products offered, and the availability of systems of credit for villagers; the investment of the Somali entrepreneurs into the villages through acts like charity; and their social interaction with villagers. The Somalis have redefined the local spaza sector, to the benefit of the villagers, and there is a degree of “xenophilia” as a result. The research also found that the growing number of Somali spaza operators in the villages was a direct result of the xenophobia experienced by this group in the urban townships. The villages around Cofimvaba benefit the Somali operator, not in a financial sense as these are not where the most profits have been made, but as sites where the traders feel safest. But although the villages are a sort of refuge, they are isolated and isolating. The Somalis resident in these areas struggle to maintain the strong ethnic group consciousness based on a strong vision of the Somali homeland, and a sense of being sojourners, hoping to relocate elsewhere.
- Full Text:
- Authors: Maselwa, Avuyile
- Date: 2017
- Subjects: Immigrant business enterprises -- South Africa -- Eastern Cape , Somalis -- South Africa -- Eastern Cape , Somalis -- South Africa -- Eastern Cape -- Public opinion , Somalis -- South Africa -- Eastern Cape -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/41738 , vital:25127
- Description: This thesis presents a study of the relationships between Somali spaza operators and the villagers living in the villages around Cofimvaba. The Somali spaza operators are operating spazas in the villages around Cofimvaba in the Intsika Yethu District Municipality (IYDM) located in the Chris Hani District Municipality (CHDM). Spaza shops are general dealers selling daily consumption items, which usually operate in the informal sector, primarily in poorer black neighbourhoods, both urban and rural. Resentment of the very visible, post-apartheid, expansion of immigrant entrepreneurship - in the informal sector, notably in spazas- has been central to South African anti-immigrant sentiment, popularly dubbed “xenophobia,” which casts foreigners, mainly black or Asian, as stealing South African resources. Foreign spaza operators, many of them Somalis, have been subject to ongoing violence and looting for well over a decade, notably in the Eastern Cape and Western Cape provinces. Yet in the deeply impoverished villages around Cofimvaba, in the former Transkei black homeland in the Eastern Cape, where Somalis play a central and growing role in spazas, such attacks are unknown. The aim of this thesis is to understand why. Careful qualitative research in several villages has indicated key reasons. These include the relative absence of South African, locally- owned spazas, and so, the lack of a local group driving xenophobic resentment; the convenience offered by Somali-owned spazas in these isolated villages, the affordability of the products offered, and the availability of systems of credit for villagers; the investment of the Somali entrepreneurs into the villages through acts like charity; and their social interaction with villagers. The Somalis have redefined the local spaza sector, to the benefit of the villagers, and there is a degree of “xenophilia” as a result. The research also found that the growing number of Somali spaza operators in the villages was a direct result of the xenophobia experienced by this group in the urban townships. The villages around Cofimvaba benefit the Somali operator, not in a financial sense as these are not where the most profits have been made, but as sites where the traders feel safest. But although the villages are a sort of refuge, they are isolated and isolating. The Somalis resident in these areas struggle to maintain the strong ethnic group consciousness based on a strong vision of the Somali homeland, and a sense of being sojourners, hoping to relocate elsewhere.
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My madam: same race, different class: living and working conditions of undocumented, migrant BaSotho domestic workers employed in black middle class houshold
- Madonsela, Koketso Njabulo Gosiame
- Authors: Madonsela, Koketso Njabulo Gosiame
- Date: 2017
- Subjects: Black women household empoyees -- South Africa , Black employers -- South Africa , Women household employees -- South Africa , Women, Sotho -- Employment -- South Africa , Businesspeople, Black -- South Africa , Migrant labor -- South Africa , Illegal aliens -- South Africa , Master and servant -- South Africa , Women, Black -- Employment -- South Africa , Industrial relations -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/35166 , vital:24337
- Description: Jacklyn Cock’s Maids and Madams is a study on domestic work in the Eastern Cape which places a focus on black domestic workers who work in white families. Cock’s study was ground-breaking research within labour development in South Africa (with regards to domestic service). The apartheid system regarded domestic work as that of social reproduction: domestic workers left their families to replenish and reproduce the labour power of white families, whose members were employed in a formal workplace. The contribution to this system, according to Cock (1989), was unbreakable because they did not earn enough money to disrupt the system. The respondents of this thesis are undocumented migrant Basotho domestic workers. These domestic workers have much in common with Cock’s respondents. For one, they leave their homes and families to replenish the labour power of black middle class families, whose members are employed in a formal workplace. The difference between this thesis and Cock’s study is that the respondents’ employers are members of the black middle class. Furthermore, the employees are undocumented Basotho domestic workers. Undocumented, migrant, Basotho domestic workers are in a similarly vulnerable position to that of Cock’s respondents. This dissertation engages with the extent to which Maids and Madams is still relevant to the living and working conditions of a new vulnerable workforce in the domestic sector: undocumented, female, Basotho domestic workers employed in black, middle-class households in Gauteng. The dissertation also finds that the relationship between the black migrant domestic worker and the black middle class employer is influenced cultural aspects of what domestic chores represent in black families, and the element of respect from employers (particularly to elderly domestic workers) or lack thereof. This dissertation underlines that the term “ousi” makes the Basotho domestic workers a collective, and not individuals. Thus the term “ousi” can be viewed as the term that takes away the identity of the domestic worker. The theoretical framework of the research is labour process theory (LPT). The new wave of labour process theorists are much more focused on the service industry. LPT is significant to this research because its focus is on the subjective experiences of the workers. This is the core purpose of the thesis. The focus of the new wave LPT involves a shift from understanding workers at a macro level to understanding the subjective experiences of the workers (in the service industry) at a micro level. This provides an appropriate framework to study the subjective working and living experiences of undocumented, migrant, Basotho domestic workers. The research design is based on qualitative research. The research made use of in-depth and semi-structured interviews. The selection of respondents was done through purposive sampling. They findings of this research highlighted the central themes in the relevant literature. However, the key findings of this research also reveal tensions and contradictions that are not explored in detail in the existing literature. For example, the relationship between the black middle class employer and the black domestic worker has tensions which originate from a cultural context. The respondents of this dissertation and their employers are of the same race, yet are of a different class.
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- Authors: Madonsela, Koketso Njabulo Gosiame
- Date: 2017
- Subjects: Black women household empoyees -- South Africa , Black employers -- South Africa , Women household employees -- South Africa , Women, Sotho -- Employment -- South Africa , Businesspeople, Black -- South Africa , Migrant labor -- South Africa , Illegal aliens -- South Africa , Master and servant -- South Africa , Women, Black -- Employment -- South Africa , Industrial relations -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/35166 , vital:24337
- Description: Jacklyn Cock’s Maids and Madams is a study on domestic work in the Eastern Cape which places a focus on black domestic workers who work in white families. Cock’s study was ground-breaking research within labour development in South Africa (with regards to domestic service). The apartheid system regarded domestic work as that of social reproduction: domestic workers left their families to replenish and reproduce the labour power of white families, whose members were employed in a formal workplace. The contribution to this system, according to Cock (1989), was unbreakable because they did not earn enough money to disrupt the system. The respondents of this thesis are undocumented migrant Basotho domestic workers. These domestic workers have much in common with Cock’s respondents. For one, they leave their homes and families to replenish the labour power of black middle class families, whose members are employed in a formal workplace. The difference between this thesis and Cock’s study is that the respondents’ employers are members of the black middle class. Furthermore, the employees are undocumented Basotho domestic workers. Undocumented, migrant, Basotho domestic workers are in a similarly vulnerable position to that of Cock’s respondents. This dissertation engages with the extent to which Maids and Madams is still relevant to the living and working conditions of a new vulnerable workforce in the domestic sector: undocumented, female, Basotho domestic workers employed in black, middle-class households in Gauteng. The dissertation also finds that the relationship between the black migrant domestic worker and the black middle class employer is influenced cultural aspects of what domestic chores represent in black families, and the element of respect from employers (particularly to elderly domestic workers) or lack thereof. This dissertation underlines that the term “ousi” makes the Basotho domestic workers a collective, and not individuals. Thus the term “ousi” can be viewed as the term that takes away the identity of the domestic worker. The theoretical framework of the research is labour process theory (LPT). The new wave of labour process theorists are much more focused on the service industry. LPT is significant to this research because its focus is on the subjective experiences of the workers. This is the core purpose of the thesis. The focus of the new wave LPT involves a shift from understanding workers at a macro level to understanding the subjective experiences of the workers (in the service industry) at a micro level. This provides an appropriate framework to study the subjective working and living experiences of undocumented, migrant, Basotho domestic workers. The research design is based on qualitative research. The research made use of in-depth and semi-structured interviews. The selection of respondents was done through purposive sampling. They findings of this research highlighted the central themes in the relevant literature. However, the key findings of this research also reveal tensions and contradictions that are not explored in detail in the existing literature. For example, the relationship between the black middle class employer and the black domestic worker has tensions which originate from a cultural context. The respondents of this dissertation and their employers are of the same race, yet are of a different class.
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Nanocomposites of sulphur-nitrogen co-doped graphene oxide nanosheets and cobalt mono carboxyphenoxy phthalocyanines for facile electrocatalysis
- Shumba, Munyaradzi, Centane, Sixolile, Chindeka, Francis, Nyokong, Tebello
- Authors: Shumba, Munyaradzi , Centane, Sixolile , Chindeka, Francis , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239665 , vital:50753 , xlink:href="https://doi.org/10.1016/j.jelechem.2017.03.006"
- Description: Nanocomposites consisting of cobalt mono carboxyphenoxy phthalocyanine (CoMCPhPc) either covalently linked to graphene oxide nanosheets (GONS), sulphur doped graphene oxide nanosheets (SDGONS), nitrogen doped graphene oxide nanosheets (NDGONS) or sulphur/nitrogen co-doped graphene oxide nanosheets (SNDGONS) or sequentially added were used to modify glassy carbon electrode. The modified electrodes were characterised using several techniques: voltammetry, X-ray photon spectroscopy and scanning electron spectroscopy before testing their activity on the detection of hydrogen peroxide at pH 7. The presence of SNDGONS had a significant improvement on the currents as compared to CoMCPhPc modification alone in both sequentially added or covalently linked to MPcs. CoMCPhPc-SNDGONS(seq)-GCE and CoMCPhPc-SDGONS(linked)-GCE resulted in impressive limits of detection and catalytic rate constant values of 1.58 nM and 5.44 nM, 3.07 × 105 M−1 s−1 and 3.01 × 103 M−1 s−1 respectively. Gibbs energy value was determined to be −21.22 kJ mol−1 for CoMCPhPc-SNDGONS(linked)-GCE indicative of a facile spontaneous electroreduction reaction on the surface of this electrode.
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- Authors: Shumba, Munyaradzi , Centane, Sixolile , Chindeka, Francis , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239665 , vital:50753 , xlink:href="https://doi.org/10.1016/j.jelechem.2017.03.006"
- Description: Nanocomposites consisting of cobalt mono carboxyphenoxy phthalocyanine (CoMCPhPc) either covalently linked to graphene oxide nanosheets (GONS), sulphur doped graphene oxide nanosheets (SDGONS), nitrogen doped graphene oxide nanosheets (NDGONS) or sulphur/nitrogen co-doped graphene oxide nanosheets (SNDGONS) or sequentially added were used to modify glassy carbon electrode. The modified electrodes were characterised using several techniques: voltammetry, X-ray photon spectroscopy and scanning electron spectroscopy before testing their activity on the detection of hydrogen peroxide at pH 7. The presence of SNDGONS had a significant improvement on the currents as compared to CoMCPhPc modification alone in both sequentially added or covalently linked to MPcs. CoMCPhPc-SNDGONS(seq)-GCE and CoMCPhPc-SDGONS(linked)-GCE resulted in impressive limits of detection and catalytic rate constant values of 1.58 nM and 5.44 nM, 3.07 × 105 M−1 s−1 and 3.01 × 103 M−1 s−1 respectively. Gibbs energy value was determined to be −21.22 kJ mol−1 for CoMCPhPc-SNDGONS(linked)-GCE indicative of a facile spontaneous electroreduction reaction on the surface of this electrode.
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Nanosecond optical nonlinearities in low symmetry phthalocyanine nanoconjugates studied using the Z-scan technique
- Nwaji, Njemuwa, Nyokong, Tebello
- Authors: Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188172 , vital:44729 , xlink:href="https://doi.org/10.1016/j.jlumin.2017.08.053"
- Description: In this study, the photophysical, and nonlinear optical limiting properties of low symmetry tris[(4-benzo[d] thiazol-2-ylphenoxy)-2-phenoxyl acetic acid phthalocyaninato] zinc (II) (3) conjugated to metallic nanoparticles have been investigated using open aperture Z-scan techniques at 532 nm. The nonlinear optical response demonstrated that the studied complex and the nanoconjugates exhibits higher excited state absorption cross-section resulting from S1 and T1 compared to ground state absorption. Enhanced optical limiting performance was observed when the complex was conjugated to nanoparticles with 3SA-AuNPs showing the best optical limiting threshold of 0.39 J/cm2.
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- Authors: Nwaji, Njemuwa , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188172 , vital:44729 , xlink:href="https://doi.org/10.1016/j.jlumin.2017.08.053"
- Description: In this study, the photophysical, and nonlinear optical limiting properties of low symmetry tris[(4-benzo[d] thiazol-2-ylphenoxy)-2-phenoxyl acetic acid phthalocyaninato] zinc (II) (3) conjugated to metallic nanoparticles have been investigated using open aperture Z-scan techniques at 532 nm. The nonlinear optical response demonstrated that the studied complex and the nanoconjugates exhibits higher excited state absorption cross-section resulting from S1 and T1 compared to ground state absorption. Enhanced optical limiting performance was observed when the complex was conjugated to nanoparticles with 3SA-AuNPs showing the best optical limiting threshold of 0.39 J/cm2.
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