Retention and dropout rates for a sample of national higher certificate students in the school of accounting
- Authors: Beck, Richard Alan
- Date: 2011
- Subjects: College dropouts -- South Africa , Learning ability , Education, Higher -- South Africa , Accounting -- Study and teaching
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8971 , http://hdl.handle.net/10948/1408 , College dropouts -- South Africa , Learning ability , Education, Higher -- South Africa , Accounting -- Study and teaching
- Description: Higher Education retention rates in South Africa are among the lowest in the world. At the Nelson Mandela Metropolitan University, a trend has been noted for National Higher Certificate (NHC) students within the Faculty of Business and Economic Science’s School of Accounting. Dropout rates have increased and graduation rates have declined for students studying NHC programmes. Retention and dropout studies have rarely been undertaken for accounting students in higher certificate or diploma programmes, which provided the motivation for this study. The study aimed to determine the dropout and retention rates of NHC students and to identify the demographic and other characteristics of dropout students relative to those who persist with their studies. Furthermore, the study identified potential barriers to academic success in the sample. An exploratory descriptive research approach was adopted to achieve the general and specific aims of the study. Data were obtained from Management Information Services about NHC dropout students and students continuing with their studies for the period 2005 to 2009. Furthermore, information was gathered for separate samples from a Language Questionnaire and the Learning Enhancement Checklist (LEC) regarding barriers to student success. High dropout rates were found in that more than half of the students dropped out. Correspondingly, the retention rates were low. The findings for the gender, cultural and language groups were interesting but no definitive conclusions could be reached regarding trends related to student dropout and retention in relation to these biographical variables. Performance in Financial Accounting I and II yielded interesting trends. Students at risk for dropping out obtained a mark of 50 percent or less on average for Financial Accounting I and 40 percent or less for Financial Accounting II. The analysis conducted to determine barriers to student success revealed that students did not prepare adequately for lectures; experienced certain difficulties in lectures, tests and VIII exams; found it difficult to manage their studies and time; and experienced financial and psychological problems. The findings of the study can be used to identify students who might drop out at an early stage. Furthermore, the findings can guide the nature of the development and support that NHC students need to succeed. The limitations of the study are noted and suggestions are made for further research into the factors related to student dropout and retention in the field of accounting.
- Full Text:
- Date Issued: 2011
- Authors: Beck, Richard Alan
- Date: 2011
- Subjects: College dropouts -- South Africa , Learning ability , Education, Higher -- South Africa , Accounting -- Study and teaching
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8971 , http://hdl.handle.net/10948/1408 , College dropouts -- South Africa , Learning ability , Education, Higher -- South Africa , Accounting -- Study and teaching
- Description: Higher Education retention rates in South Africa are among the lowest in the world. At the Nelson Mandela Metropolitan University, a trend has been noted for National Higher Certificate (NHC) students within the Faculty of Business and Economic Science’s School of Accounting. Dropout rates have increased and graduation rates have declined for students studying NHC programmes. Retention and dropout studies have rarely been undertaken for accounting students in higher certificate or diploma programmes, which provided the motivation for this study. The study aimed to determine the dropout and retention rates of NHC students and to identify the demographic and other characteristics of dropout students relative to those who persist with their studies. Furthermore, the study identified potential barriers to academic success in the sample. An exploratory descriptive research approach was adopted to achieve the general and specific aims of the study. Data were obtained from Management Information Services about NHC dropout students and students continuing with their studies for the period 2005 to 2009. Furthermore, information was gathered for separate samples from a Language Questionnaire and the Learning Enhancement Checklist (LEC) regarding barriers to student success. High dropout rates were found in that more than half of the students dropped out. Correspondingly, the retention rates were low. The findings for the gender, cultural and language groups were interesting but no definitive conclusions could be reached regarding trends related to student dropout and retention in relation to these biographical variables. Performance in Financial Accounting I and II yielded interesting trends. Students at risk for dropping out obtained a mark of 50 percent or less on average for Financial Accounting I and 40 percent or less for Financial Accounting II. The analysis conducted to determine barriers to student success revealed that students did not prepare adequately for lectures; experienced certain difficulties in lectures, tests and VIII exams; found it difficult to manage their studies and time; and experienced financial and psychological problems. The findings of the study can be used to identify students who might drop out at an early stage. Furthermore, the findings can guide the nature of the development and support that NHC students need to succeed. The limitations of the study are noted and suggestions are made for further research into the factors related to student dropout and retention in the field of accounting.
- Full Text:
- Date Issued: 2011
Using information visualization techniques to support web service discovery
- Authors: Beets, Simone
- Date: 2011
- Subjects: Information visualization , Web services , Information visualization -- Computer programs
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10457 , http://hdl.handle.net/10948/1659 , Information visualization , Web services , Information visualization -- Computer programs
- Description: The increasing number of web services published over the Web highlights the need for an effective method for users to find appropriate web services. Existing web service discovery methods do not effectively aid a user in finding suitable web services. The current methods provide textual lists of web services that the user is required to explore and manually evaluate. Thus, these methods lead to time-consuming and ineffective web service discovery. The aim of this research was to investigate using information visualization (IV) techniques to effectively support web service discovery. The node-and-link network IV technique was selected as the most appropriate IV technique to visualize web service collections. A prototype, called SerViz, was developed as a tool for interactive visualization of web service collections incorporating the node-and-link IV technique and an alphabetical list-based technique. SerViz used the Programmable Web web service collection as the sample web service collection. A usability evaluation was conducted to compare these techniques. Ninety percent of participants preferred the network IV technique for visualizing web service collections. The network IV technique was also faster for browsing. Several usability problems were identified with the network IV technique. This motivated a need for implementing an alternative IV technique in SerViz. The node-and-link tree IV technique was selected as it was more structured than the network IV technique. A usability evaluation was conducted to compare the network and tree IV techniques. Participants slightly preferred the tree IV technique as the technique to visualize web service collections. The tree IV technique was faster for browsing the web service collection while the network IV technique was faster for searching and filtering. This research has determined that IV techniques can be used to effectively support web service discovery. Future work will involve using IV techniques to support collaborative web service discovery. Keywords: Web Service Discovery, Information Visualization, Web Service Collections, Information Visualization Techniques.
- Full Text:
- Date Issued: 2011
- Authors: Beets, Simone
- Date: 2011
- Subjects: Information visualization , Web services , Information visualization -- Computer programs
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10457 , http://hdl.handle.net/10948/1659 , Information visualization , Web services , Information visualization -- Computer programs
- Description: The increasing number of web services published over the Web highlights the need for an effective method for users to find appropriate web services. Existing web service discovery methods do not effectively aid a user in finding suitable web services. The current methods provide textual lists of web services that the user is required to explore and manually evaluate. Thus, these methods lead to time-consuming and ineffective web service discovery. The aim of this research was to investigate using information visualization (IV) techniques to effectively support web service discovery. The node-and-link network IV technique was selected as the most appropriate IV technique to visualize web service collections. A prototype, called SerViz, was developed as a tool for interactive visualization of web service collections incorporating the node-and-link IV technique and an alphabetical list-based technique. SerViz used the Programmable Web web service collection as the sample web service collection. A usability evaluation was conducted to compare these techniques. Ninety percent of participants preferred the network IV technique for visualizing web service collections. The network IV technique was also faster for browsing. Several usability problems were identified with the network IV technique. This motivated a need for implementing an alternative IV technique in SerViz. The node-and-link tree IV technique was selected as it was more structured than the network IV technique. A usability evaluation was conducted to compare the network and tree IV techniques. Participants slightly preferred the tree IV technique as the technique to visualize web service collections. The tree IV technique was faster for browsing the web service collection while the network IV technique was faster for searching and filtering. This research has determined that IV techniques can be used to effectively support web service discovery. Future work will involve using IV techniques to support collaborative web service discovery. Keywords: Web Service Discovery, Information Visualization, Web Service Collections, Information Visualization Techniques.
- Full Text:
- Date Issued: 2011
The diversity of aquatic insects in the Tsitsikamma region, with implications for aquatic ecosystem conservation
- Authors: Bellingan, Terence Andrew
- Date: 2011
- Subjects: Aquatic insects -- South Africa -- Tsitsikamma , Aquatic insects -- Classification -- South Africa -- Tsitsikamma , Aquatic ecology -- South Africa -- Tsitsikamma , Ecosystem management -- South Africa -- Tsitsikamma , Stream conservation -- South Africa -- Tsitsikamma
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5664 , http://hdl.handle.net/10962/d1005348 , Aquatic insects -- South Africa -- Tsitsikamma , Aquatic insects -- Classification -- South Africa -- Tsitsikamma , Aquatic ecology -- South Africa -- Tsitsikamma , Ecosystem management -- South Africa -- Tsitsikamma , Stream conservation -- South Africa -- Tsitsikamma
- Description: As a result of research carried out within the last decade to assess the diversity of macroinvertebrates of the Salt River in the Western Cape Province, South Africa, surveys of macroinvertebrates of 20 sites on 11 selected rivers from the same mountain range source were undertaken. This was done to make a preliminary assessment of the conservation status of the rivers of this region. Aquatic insects from the orders Ephemeroptera, Odonata, Plecoptera, Megaloptera, Trichoptera and the dipteran family Simuliidae were collected using techniques to maximize the number of taxa found. The insects collected were identified to species level where possible. Water physicochemical parameters were recorded at all sites for each sampling trip to characterize these rivers and to establish a set of baseline data for future comparisons. These parameters included measurements made on site and analysis of the concentrations of all the major ions in water samples in the laboratory. Multivariate analyses including Principle Components Analysis and Canonical Correspondence Analysis were used to reveal patterns within the water physicochemistry and species distributional data. Results include the identification of 123 species from 70 genera and 30 families. A total of 31 species were found to be undescribed, of which 17 were not previously collected and are thus completely new to science. In addition, four of these species could not be placed into any known genus. The analysis of water physicochemistry showed a clear distinction between rivers of Table Mountain sandstone and Bokkeveld shale origin. Downstream effects of anthropogenic influences were discernable too. Distinct macroinvertebrate assemblages were found based upon stream order and water chemistry composition. pH proved to be the most important driver of invertebrate assemblage composition. The high levels of endemism of the macroinvertebrates found within the upper reaches of these rivers and their degree of ecological specialization make these systems a priority for the conservation of aquatic biodiversity on a national and global scale.
- Full Text:
- Date Issued: 2011
- Authors: Bellingan, Terence Andrew
- Date: 2011
- Subjects: Aquatic insects -- South Africa -- Tsitsikamma , Aquatic insects -- Classification -- South Africa -- Tsitsikamma , Aquatic ecology -- South Africa -- Tsitsikamma , Ecosystem management -- South Africa -- Tsitsikamma , Stream conservation -- South Africa -- Tsitsikamma
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5664 , http://hdl.handle.net/10962/d1005348 , Aquatic insects -- South Africa -- Tsitsikamma , Aquatic insects -- Classification -- South Africa -- Tsitsikamma , Aquatic ecology -- South Africa -- Tsitsikamma , Ecosystem management -- South Africa -- Tsitsikamma , Stream conservation -- South Africa -- Tsitsikamma
- Description: As a result of research carried out within the last decade to assess the diversity of macroinvertebrates of the Salt River in the Western Cape Province, South Africa, surveys of macroinvertebrates of 20 sites on 11 selected rivers from the same mountain range source were undertaken. This was done to make a preliminary assessment of the conservation status of the rivers of this region. Aquatic insects from the orders Ephemeroptera, Odonata, Plecoptera, Megaloptera, Trichoptera and the dipteran family Simuliidae were collected using techniques to maximize the number of taxa found. The insects collected were identified to species level where possible. Water physicochemical parameters were recorded at all sites for each sampling trip to characterize these rivers and to establish a set of baseline data for future comparisons. These parameters included measurements made on site and analysis of the concentrations of all the major ions in water samples in the laboratory. Multivariate analyses including Principle Components Analysis and Canonical Correspondence Analysis were used to reveal patterns within the water physicochemistry and species distributional data. Results include the identification of 123 species from 70 genera and 30 families. A total of 31 species were found to be undescribed, of which 17 were not previously collected and are thus completely new to science. In addition, four of these species could not be placed into any known genus. The analysis of water physicochemistry showed a clear distinction between rivers of Table Mountain sandstone and Bokkeveld shale origin. Downstream effects of anthropogenic influences were discernable too. Distinct macroinvertebrate assemblages were found based upon stream order and water chemistry composition. pH proved to be the most important driver of invertebrate assemblage composition. The high levels of endemism of the macroinvertebrates found within the upper reaches of these rivers and their degree of ecological specialization make these systems a priority for the conservation of aquatic biodiversity on a national and global scale.
- Full Text:
- Date Issued: 2011
The effectiveness of poverty alleviation initiatives in Buffalo City Metropolitan municipality
- Authors: Benya, Zoliswa (Nqolase)
- Date: 2011
- Subjects: Poverty -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Poverty -- Government policy -- South Africa -- Eastern Cape , Economic assistance, Domestic -- South Africa -- Eastern Cape , Squatter settlements -- South Africa -- Eastern Cape , Poor -- Services for
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9048 , http://hdl.handle.net/10948/1613 , Poverty -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Poverty -- Government policy -- South Africa -- Eastern Cape , Economic assistance, Domestic -- South Africa -- Eastern Cape , Squatter settlements -- South Africa -- Eastern Cape , Poor -- Services for
- Description: The South African democratic government has, since 1994, implemented various programs that aim to alleviate poverty through policy interventions. The Provincial Growth and Development Plan (Eastern Cape 2004-2014) commit its self to halving poverty by 2014. The research seeks to evaluate the effectiveness of poverty alleviation initiatives in Buffalo City Metropolitan Municipality (BCMM), East London; focussing in Nompumelelo informal settlement. The study applied quantitative and qualitative approaches for biographical and socio economic information; and for in-depth understanding and verification respectively. Data collection was through structured interviews and survey questionnaires. The findings reveal that there are random, short-term poverty alleviation initiatives taking place in Nompumelelo informal settlement area. Projects that could have been self-sustaining collapsed due to lack of skills and training. The study indicates that the level of unemployment is high at 68 percent.
- Full Text:
- Date Issued: 2011
- Authors: Benya, Zoliswa (Nqolase)
- Date: 2011
- Subjects: Poverty -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Poverty -- Government policy -- South Africa -- Eastern Cape , Economic assistance, Domestic -- South Africa -- Eastern Cape , Squatter settlements -- South Africa -- Eastern Cape , Poor -- Services for
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9048 , http://hdl.handle.net/10948/1613 , Poverty -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape , Poverty -- Government policy -- South Africa -- Eastern Cape , Economic assistance, Domestic -- South Africa -- Eastern Cape , Squatter settlements -- South Africa -- Eastern Cape , Poor -- Services for
- Description: The South African democratic government has, since 1994, implemented various programs that aim to alleviate poverty through policy interventions. The Provincial Growth and Development Plan (Eastern Cape 2004-2014) commit its self to halving poverty by 2014. The research seeks to evaluate the effectiveness of poverty alleviation initiatives in Buffalo City Metropolitan Municipality (BCMM), East London; focussing in Nompumelelo informal settlement. The study applied quantitative and qualitative approaches for biographical and socio economic information; and for in-depth understanding and verification respectively. Data collection was through structured interviews and survey questionnaires. The findings reveal that there are random, short-term poverty alleviation initiatives taking place in Nompumelelo informal settlement area. Projects that could have been self-sustaining collapsed due to lack of skills and training. The study indicates that the level of unemployment is high at 68 percent.
- Full Text:
- Date Issued: 2011
The existence of the value premium on the Johannesburg Stock Exchange from 1972 to 2001 and extrapolation as explanation
- Authors: Beukes, Anna
- Date: 2011
- Subjects: Johannesburg Stock Exchange Stocks -- Prices -- South Africa Rational expectations (Economic theory) Investments -- Psychological aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:977 , http://hdl.handle.net/10962/d1002711
- Description: This study investigates the existence of the value premium in South Africa’s equity market, and tests extrapolation as a possible explanation for it. The value premium refers to the widely reported superior performance of share price returns of value companies compared to growth companies. The value premium represents an anomaly in mainstream rational finance theory, because it should not persist, unless it could be explained as the result of some composite form of risk. What is highly vexing is the fact that the value premium not only persists in most financial markets over a long period, but that the risk explanation cannot be upheld convincingly. This contributed to the rise of behavioral finance, an approach which introduces psychological factors to provide new explanations for financial phenomena. The behavioral finance explanation for the value premium observation is extrapolation (the tendency to project recent experience too far into the future). This study applies propositions and methods from behavioral finance to investigate the South African equity market. The existence of a value premium in South Africa was investigated by using twenty-nine years’ worth of accounting and share price data. The study employed one- and two-dimensional tests for portfolio formation, and tracked share price returns for up to five years after portfolio formation. The results indicated that a statistically and economically significant value premium existed in South Africa for the period between 1972 and 2001. Extrapolation as a potential explanation for the value premium observation was investigated by applying internationally used methods. Extrapolation was found to provide a robust explanation for the South African value premium.
- Full Text:
- Date Issued: 2011
- Authors: Beukes, Anna
- Date: 2011
- Subjects: Johannesburg Stock Exchange Stocks -- Prices -- South Africa Rational expectations (Economic theory) Investments -- Psychological aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:977 , http://hdl.handle.net/10962/d1002711
- Description: This study investigates the existence of the value premium in South Africa’s equity market, and tests extrapolation as a possible explanation for it. The value premium refers to the widely reported superior performance of share price returns of value companies compared to growth companies. The value premium represents an anomaly in mainstream rational finance theory, because it should not persist, unless it could be explained as the result of some composite form of risk. What is highly vexing is the fact that the value premium not only persists in most financial markets over a long period, but that the risk explanation cannot be upheld convincingly. This contributed to the rise of behavioral finance, an approach which introduces psychological factors to provide new explanations for financial phenomena. The behavioral finance explanation for the value premium observation is extrapolation (the tendency to project recent experience too far into the future). This study applies propositions and methods from behavioral finance to investigate the South African equity market. The existence of a value premium in South Africa was investigated by using twenty-nine years’ worth of accounting and share price data. The study employed one- and two-dimensional tests for portfolio formation, and tracked share price returns for up to five years after portfolio formation. The results indicated that a statistically and economically significant value premium existed in South Africa for the period between 1972 and 2001. Extrapolation as a potential explanation for the value premium observation was investigated by applying internationally used methods. Extrapolation was found to provide a robust explanation for the South African value premium.
- Full Text:
- Date Issued: 2011
Effect of alkaline pre-treatments on the synergistic enzymatic hydrolysis of sugarcane (Saccharum officinarum) bagasse by Clostridium cellulovorans XynA, ManA and ArfA
- Authors: Beukes, Natasha
- Date: 2011
- Subjects: Sugarcane -- Biotechnology Lignocellulose -- Biotechnology Renewable energy sources Hydrolysis Enzymes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3952 , http://hdl.handle.net/10962/d1004011
- Description: The continual increase in industrialization and global population has increased the dependency and demand on traditional fossil fuels for energy; however, there are limited amounts of fossil fuels available. The slow depletion of fossil fuels has sparked a fresh interest in renewable sources such as lignocellulose to produce a variety of biofuels, such as biogases (e.g. methane), bioethanol, biodiesel and a variety of other solvents and economically valuable by-products. Agricultural crop wastes produced in surplus are typically lignocellulosic in composition and thus partially recalcitrant to enzymatic degradation. The recalcitrant nature of plant biomass and the inability to obtain complete enzymatic hydrolysis has led to the establishment of various pre-treatment strategies. Alkaline pre-treatments increase the accessibility of the exposed surface to enzymatic hydrolysis through the removal of acetyl and uronic acid substituents on hemicellulose. Unlike the use of steam and acid pre-treatments, alkaline pre-treatments solubilize lignin and a small percentage of the hemicellulose, increasing enzyme accessibility and thus the hydrolysis of lignocellulose. The majority of Clostridium cellulovorans associated enzyme synergy studies have been devoted to an understanding of the cellulolytic and hemi-cellulolytic degradation of plant cell walls. However, little is known about the effect of various physical and chemical pre-treatments on the synergistic enzymatic degradation of plant biomass and possible depolymerization of plant cell walls. This study investigates the use of slake lime, sodium hydroxide and ammonium hydroxide to pre-treat sugarcane bagasse under mild conditions and elucidates potentially important synergistic associations between the C. cellulovorans enzymes for the enhanced degradation of lignocellulose. The primary aims of the study were addressed using of a variety of techniques. This included suitable vector constructs for the expression and purification of recombinant C. cellulovorans enzymes, identification of the effects of various pre-treatments on enzyme synergy, and identification of the resultant reducing sugars and phenolic compounds (released during the pre-treatment of the bagasse). This study also made use of physical and chemical pre-treatment methods, protein purification using affinity, high performance liquid and thin layer chromatography, mass spectrometry, sodium dodecyl sulphate and fluorophore-assisted polyacrylamide gel electrophoresis (FACE) , enzymatic degradation and synergy studies with various substrates indirectly using the 3, 4-dinitrosalicylic acid (DNS) reducing sugar assay. From this investigation, the following conclusions were made: alkaline pre-treatment successfully solublised, redistributed and removed lignin from the bagasse, increasing the digestibility of the substrates. In summary, the most effective pre-treatment employed 0.114 M ammonium hydroxide / gram bagasse at 70°C for 36 hours, followed by hydrolysis with an enzyme cocktail containing 25% ManA and 75% XynA. This increased the production of sugars approximately 13-fold. Analysis of the sugars produced by the synergistic hydrolysis of sugarcane bagasse (SCB) indicated the presence of xylose, indicating that the enzymes are potentially bifunctional under certain conditions. This study indicated that the use of mild pre-treatment conditions sufficiently removed a large portion of lignin without affecting the hemicellulose moiety of the SCB. This facilitated the potential use of the hemicellulose component for the production of valuable products (e.g. xylitol) in addition to the production of bioethanol. Thus, the potential use of additional components of holocellulose may generate an additional biotechnological benefit and allow a certain degree of flexibility in the biofuel industry, depending on consumer and industrial needs.
- Full Text:
- Date Issued: 2011
- Authors: Beukes, Natasha
- Date: 2011
- Subjects: Sugarcane -- Biotechnology Lignocellulose -- Biotechnology Renewable energy sources Hydrolysis Enzymes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3952 , http://hdl.handle.net/10962/d1004011
- Description: The continual increase in industrialization and global population has increased the dependency and demand on traditional fossil fuels for energy; however, there are limited amounts of fossil fuels available. The slow depletion of fossil fuels has sparked a fresh interest in renewable sources such as lignocellulose to produce a variety of biofuels, such as biogases (e.g. methane), bioethanol, biodiesel and a variety of other solvents and economically valuable by-products. Agricultural crop wastes produced in surplus are typically lignocellulosic in composition and thus partially recalcitrant to enzymatic degradation. The recalcitrant nature of plant biomass and the inability to obtain complete enzymatic hydrolysis has led to the establishment of various pre-treatment strategies. Alkaline pre-treatments increase the accessibility of the exposed surface to enzymatic hydrolysis through the removal of acetyl and uronic acid substituents on hemicellulose. Unlike the use of steam and acid pre-treatments, alkaline pre-treatments solubilize lignin and a small percentage of the hemicellulose, increasing enzyme accessibility and thus the hydrolysis of lignocellulose. The majority of Clostridium cellulovorans associated enzyme synergy studies have been devoted to an understanding of the cellulolytic and hemi-cellulolytic degradation of plant cell walls. However, little is known about the effect of various physical and chemical pre-treatments on the synergistic enzymatic degradation of plant biomass and possible depolymerization of plant cell walls. This study investigates the use of slake lime, sodium hydroxide and ammonium hydroxide to pre-treat sugarcane bagasse under mild conditions and elucidates potentially important synergistic associations between the C. cellulovorans enzymes for the enhanced degradation of lignocellulose. The primary aims of the study were addressed using of a variety of techniques. This included suitable vector constructs for the expression and purification of recombinant C. cellulovorans enzymes, identification of the effects of various pre-treatments on enzyme synergy, and identification of the resultant reducing sugars and phenolic compounds (released during the pre-treatment of the bagasse). This study also made use of physical and chemical pre-treatment methods, protein purification using affinity, high performance liquid and thin layer chromatography, mass spectrometry, sodium dodecyl sulphate and fluorophore-assisted polyacrylamide gel electrophoresis (FACE) , enzymatic degradation and synergy studies with various substrates indirectly using the 3, 4-dinitrosalicylic acid (DNS) reducing sugar assay. From this investigation, the following conclusions were made: alkaline pre-treatment successfully solublised, redistributed and removed lignin from the bagasse, increasing the digestibility of the substrates. In summary, the most effective pre-treatment employed 0.114 M ammonium hydroxide / gram bagasse at 70°C for 36 hours, followed by hydrolysis with an enzyme cocktail containing 25% ManA and 75% XynA. This increased the production of sugars approximately 13-fold. Analysis of the sugars produced by the synergistic hydrolysis of sugarcane bagasse (SCB) indicated the presence of xylose, indicating that the enzymes are potentially bifunctional under certain conditions. This study indicated that the use of mild pre-treatment conditions sufficiently removed a large portion of lignin without affecting the hemicellulose moiety of the SCB. This facilitated the potential use of the hemicellulose component for the production of valuable products (e.g. xylitol) in addition to the production of bioethanol. Thus, the potential use of additional components of holocellulose may generate an additional biotechnological benefit and allow a certain degree of flexibility in the biofuel industry, depending on consumer and industrial needs.
- Full Text:
- Date Issued: 2011
Macrophytes as indicators of physico-chemical factors in South African Estuaries
- Authors: Bezuidenhout, Chantel
- Date: 2011
- Subjects: Estuarine ecology -- South Africa , Aquatic plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10597 , http://hdl.handle.net/10948/1387 , Estuarine ecology -- South Africa , Aquatic plants -- South Africa
- Description: This study investigated the response of macrophytes to physico-chemical factors in seven South African estuaries and showed that dominant salt marsh species that occur in different estuaries respond to the same environmental factors. The most important variables influencing distribution were elevation, water level, sediment- and groundwater electrical conductivity and depth to the water table. In permanently open estuaries (Kromme and Olifants) transect surveys identified three distinct vegetation zones i.e. submerged macrophytes, intertidal salt marsh and supratidal salt marsh. In the Kromme Estuary intertidal salt marsh (81.2 ha) covered extensive areas, whereas supratidal (143 ha) and floodplain (797.1 ha) salt marsh were dominant in the Olifants Estuary. Transect surveys identified four distinct vegetation zones (submerged macrophytes, intertidal salt marsh, supratidal salt marsh and reeds and sedges) in the temporarily open/closed estuaries (Mngazi, Great Brak, East Kleinemonde and Seekoei estuaries), although all zones did not occur in all of the estuaries sampled. In the Mngazi Estuary reeds and sedges (1.09 ha) covered extensive areas (no submerged or salt marsh vegetation was present), whereas salt marsh (Great Brak 24.45 ha, East Kleinemonde 17.44 ha and Seekoei 12.9 ha) vegetation was dominant in the other estuaries. Despite the geographic differences, environmental factors influencing macrophyte distribution were similar in all estuaries. Canonical Correspondence Analysis showed that vegetation distribution was significantly affected by elevation, groundwater and sediment electrical conductivity and depth to groundwater. Supratidal species were associated with a greater depth to groundwater (1.2 ± 0.04 m; n = 153) compared to intertidal species (0.5 ± 0.01 m; n = 361). Correlation analysis showed that water level and rainfall were correlated with groundwater electrical conductivity in the lower and upper intertidal zones for all the estuaries sampled. These data indicate the influence of the estuary channel on the physico-chemical conditions of the salt marsh. Low rainfall (16 ± 3.3 mm per annum) in the Olifants Estuary (30-100 mS cm-1) and lack of freshwater flooding in the Kromme Estuary (42-115 mS cm-1) have resulted in high sediment electrical conductivity by comparison with the other estuaries sampled. In the Orange River Estuary approximately 70 ha of salt marsh have been lost through the building of a causeway and flood control levees. Even though salt marsh vegetation can tolerate hypersaline sediments by using the less saline water table, the groundwater at the Orange River Estuary was too saline (avg. of 90.3 ± 6.55 mS cm-1, n = 38) to be of use to the dominant floodplain species, Sarcocornia pillansii. Freshwater inflow to estuaries is important in maintaining longitudinal salinity gradients and reducing hypersaline conditions. In the Olifants Estuary and the Orange River Estuary where supratidal salt marsh is dominant, freshwater inflow is important in raising the water level and maintaining the depth to groundwater and salinity. Lack of freshwater inflow to the Kromme Estuary has highlighted the importance of rainfall in maintaining sediment salinity within acceptable ranges for the salt marsh. Macrophytes are relatively good indicators of physico-chemical factors in estuaries. From an understanding of the response of specific species to environmental variables, ecological water requirements can be set and sensitive areas can be rehabilitated.
- Full Text:
- Date Issued: 2011
- Authors: Bezuidenhout, Chantel
- Date: 2011
- Subjects: Estuarine ecology -- South Africa , Aquatic plants -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10597 , http://hdl.handle.net/10948/1387 , Estuarine ecology -- South Africa , Aquatic plants -- South Africa
- Description: This study investigated the response of macrophytes to physico-chemical factors in seven South African estuaries and showed that dominant salt marsh species that occur in different estuaries respond to the same environmental factors. The most important variables influencing distribution were elevation, water level, sediment- and groundwater electrical conductivity and depth to the water table. In permanently open estuaries (Kromme and Olifants) transect surveys identified three distinct vegetation zones i.e. submerged macrophytes, intertidal salt marsh and supratidal salt marsh. In the Kromme Estuary intertidal salt marsh (81.2 ha) covered extensive areas, whereas supratidal (143 ha) and floodplain (797.1 ha) salt marsh were dominant in the Olifants Estuary. Transect surveys identified four distinct vegetation zones (submerged macrophytes, intertidal salt marsh, supratidal salt marsh and reeds and sedges) in the temporarily open/closed estuaries (Mngazi, Great Brak, East Kleinemonde and Seekoei estuaries), although all zones did not occur in all of the estuaries sampled. In the Mngazi Estuary reeds and sedges (1.09 ha) covered extensive areas (no submerged or salt marsh vegetation was present), whereas salt marsh (Great Brak 24.45 ha, East Kleinemonde 17.44 ha and Seekoei 12.9 ha) vegetation was dominant in the other estuaries. Despite the geographic differences, environmental factors influencing macrophyte distribution were similar in all estuaries. Canonical Correspondence Analysis showed that vegetation distribution was significantly affected by elevation, groundwater and sediment electrical conductivity and depth to groundwater. Supratidal species were associated with a greater depth to groundwater (1.2 ± 0.04 m; n = 153) compared to intertidal species (0.5 ± 0.01 m; n = 361). Correlation analysis showed that water level and rainfall were correlated with groundwater electrical conductivity in the lower and upper intertidal zones for all the estuaries sampled. These data indicate the influence of the estuary channel on the physico-chemical conditions of the salt marsh. Low rainfall (16 ± 3.3 mm per annum) in the Olifants Estuary (30-100 mS cm-1) and lack of freshwater flooding in the Kromme Estuary (42-115 mS cm-1) have resulted in high sediment electrical conductivity by comparison with the other estuaries sampled. In the Orange River Estuary approximately 70 ha of salt marsh have been lost through the building of a causeway and flood control levees. Even though salt marsh vegetation can tolerate hypersaline sediments by using the less saline water table, the groundwater at the Orange River Estuary was too saline (avg. of 90.3 ± 6.55 mS cm-1, n = 38) to be of use to the dominant floodplain species, Sarcocornia pillansii. Freshwater inflow to estuaries is important in maintaining longitudinal salinity gradients and reducing hypersaline conditions. In the Olifants Estuary and the Orange River Estuary where supratidal salt marsh is dominant, freshwater inflow is important in raising the water level and maintaining the depth to groundwater and salinity. Lack of freshwater inflow to the Kromme Estuary has highlighted the importance of rainfall in maintaining sediment salinity within acceptable ranges for the salt marsh. Macrophytes are relatively good indicators of physico-chemical factors in estuaries. From an understanding of the response of specific species to environmental variables, ecological water requirements can be set and sensitive areas can be rehabilitated.
- Full Text:
- Date Issued: 2011
Financial integration in East Africa: evidence from interest rate pass-through analysis
- Authors: Bholla, Zohaib Salim
- Date: 2011
- Subjects: East African Community -- Economic integration East African Community -- Economic conditions -- 21st century Interest rates -- Africa, East Interest rates -- Econometric models -- Africa, East Interest rates -- Effect of inflation on -- Africa, East Banks and banking -- Africa, East
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1044 , http://hdl.handle.net/10962/d1006131
- Description: The successful launch of the European Monetary Union (EMU) raised an already ever growing interest in the economics of monetary integration and the formation of monetary unions around the world. Following the EMU experience, countries have considered forming a monetary union amongst themselves. The East African Community (EAC), comprising the three original member countries Kenya, Tanzania and Uganda and now including Burundi and Rwanda, is an example of such a group of countries that seek to form a monetary union. This study aims to identify the current level of financial integration amongst the East African countries. In order to do so the study examines whether the pass-through of monetary policy in the five countries has become similar over time. This is to provide an indication of the extent to which the nominal convergence criteria amongst the member countries have been met. The results of the study provide an indication of whether the formation of a monetary union in East Africa is possible. The empirical analysis used in this study included stationarity tests, four tests of co integration and an asymmetric error correction model to investigate whether the pass-through of monetary policy transmission in the five countries has become more similar over the ten year sample period from 1999 to 2008. The analysis uses three interest rates and 6-year rolling windows to identify the extent of macroeconomic convergence that prevails within the EAC, and consequently whether the formation of a monetary union is possible. The results suggest that the magnitude of the convergence amongst the countries remain low and there are significant rigidities in the deposit and lending rates over time, however the passthrough has improved with respect to the lending rate but not the deposit rate. The overall conclusion of the study suggests that an EAC wide monetary union is currently not possible based on the evidence provided from the pass-through analysis.
- Full Text:
- Date Issued: 2011
- Authors: Bholla, Zohaib Salim
- Date: 2011
- Subjects: East African Community -- Economic integration East African Community -- Economic conditions -- 21st century Interest rates -- Africa, East Interest rates -- Econometric models -- Africa, East Interest rates -- Effect of inflation on -- Africa, East Banks and banking -- Africa, East
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1044 , http://hdl.handle.net/10962/d1006131
- Description: The successful launch of the European Monetary Union (EMU) raised an already ever growing interest in the economics of monetary integration and the formation of monetary unions around the world. Following the EMU experience, countries have considered forming a monetary union amongst themselves. The East African Community (EAC), comprising the three original member countries Kenya, Tanzania and Uganda and now including Burundi and Rwanda, is an example of such a group of countries that seek to form a monetary union. This study aims to identify the current level of financial integration amongst the East African countries. In order to do so the study examines whether the pass-through of monetary policy in the five countries has become similar over time. This is to provide an indication of the extent to which the nominal convergence criteria amongst the member countries have been met. The results of the study provide an indication of whether the formation of a monetary union in East Africa is possible. The empirical analysis used in this study included stationarity tests, four tests of co integration and an asymmetric error correction model to investigate whether the pass-through of monetary policy transmission in the five countries has become more similar over the ten year sample period from 1999 to 2008. The analysis uses three interest rates and 6-year rolling windows to identify the extent of macroeconomic convergence that prevails within the EAC, and consequently whether the formation of a monetary union is possible. The results suggest that the magnitude of the convergence amongst the countries remain low and there are significant rigidities in the deposit and lending rates over time, however the passthrough has improved with respect to the lending rate but not the deposit rate. The overall conclusion of the study suggests that an EAC wide monetary union is currently not possible based on the evidence provided from the pass-through analysis.
- Full Text:
- Date Issued: 2011
The obligation of non-discrimination under the General Agreement on Trade in Services (GATS) and the agreement on Trade-related aspects of Intellectual Property Rights (TRIPS): a developmental perspective
- Authors: Bidie, Simphiwe Sincere
- Date: 2011
- Subjects: Food -- Relief -- Law -- Legislation , Food supply -- Law and legislation , Foreign trade regulation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11113 , http://hdl.handle.net/10353/338 , Food -- Relief -- Law -- Legislation , Food supply -- Law and legislation , Foreign trade regulation
- Description: The non-discrimination obligation has existed since the twelfth century. It has been practiced since then, changing from a conditional to unconditional form with the passage of time. It became firmly applied unconditionally at the multilateral level in 1947 after the formation of the GATT trading system upon which several countries based their trading relations. In 1995 when the WTO was formed, the underlying principles of the GATT 1947 became part of the WTO trading system, including the non-discrimination obligation. When countries join the WTO they automatically become subject to the non-discrimination obligation. The ever increasing value of services and trade in the value of intellectual property has necessitated a look at the fundamental principles of world trade that countries have to adhere to in their trade relations. Incidentally, countries are not at the same level economically, hence one of the purposes of the WTO is to facilitate development in developing countries. Accordingly, this requires different application and/or interpretation of these fundamental principles in different situations, depending on the development level of each Member country. Amongst the five principles that underlie the international trading system, the non-discrimination principle is the focus of this study. The sustainability of the entire economic relations between WTO Member countries is dependent upon their fair compliance with this obligation. The obligation is found in Articles II and XVII of the GATS and Articles 3 and 4 of the TRIPS. The Membership of the WTO is made up of developed and developing countries. As a result of the fundamental nature of the obligation it is imperative that the scope and interpretation of this obligation, as developed by WTO adjudicating bodies, be analysed to determine if the obligation’s application and/or interpretation satisfies the above fundamental object and purpose of the multilateral system of trade. The intention here is at all times to show the importance that the non-discrimination obligation carries in international economic and legal interactions and how non-observance of this obligation would negatively affect relations between Member countries of the WTO.
- Full Text:
- Date Issued: 2011
- Authors: Bidie, Simphiwe Sincere
- Date: 2011
- Subjects: Food -- Relief -- Law -- Legislation , Food supply -- Law and legislation , Foreign trade regulation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11113 , http://hdl.handle.net/10353/338 , Food -- Relief -- Law -- Legislation , Food supply -- Law and legislation , Foreign trade regulation
- Description: The non-discrimination obligation has existed since the twelfth century. It has been practiced since then, changing from a conditional to unconditional form with the passage of time. It became firmly applied unconditionally at the multilateral level in 1947 after the formation of the GATT trading system upon which several countries based their trading relations. In 1995 when the WTO was formed, the underlying principles of the GATT 1947 became part of the WTO trading system, including the non-discrimination obligation. When countries join the WTO they automatically become subject to the non-discrimination obligation. The ever increasing value of services and trade in the value of intellectual property has necessitated a look at the fundamental principles of world trade that countries have to adhere to in their trade relations. Incidentally, countries are not at the same level economically, hence one of the purposes of the WTO is to facilitate development in developing countries. Accordingly, this requires different application and/or interpretation of these fundamental principles in different situations, depending on the development level of each Member country. Amongst the five principles that underlie the international trading system, the non-discrimination principle is the focus of this study. The sustainability of the entire economic relations between WTO Member countries is dependent upon their fair compliance with this obligation. The obligation is found in Articles II and XVII of the GATS and Articles 3 and 4 of the TRIPS. The Membership of the WTO is made up of developed and developing countries. As a result of the fundamental nature of the obligation it is imperative that the scope and interpretation of this obligation, as developed by WTO adjudicating bodies, be analysed to determine if the obligation’s application and/or interpretation satisfies the above fundamental object and purpose of the multilateral system of trade. The intention here is at all times to show the importance that the non-discrimination obligation carries in international economic and legal interactions and how non-observance of this obligation would negatively affect relations between Member countries of the WTO.
- Full Text:
- Date Issued: 2011
Contributions of women to family Business as evidence in the Eastern Cape
- Authors: Billson, Leonie
- Date: 2011
- Subjects: Family-owned business enterprises -- South Africa -- Eastern Cape , Businesswomen -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8585 , http://hdl.handle.net/10948/1608 , Family-owned business enterprises -- South Africa -- Eastern Cape , Businesswomen -- South Africa -- Eastern Cape
- Description: Family businesses are operating throughout the world and suggested to be the predominant way of doing business. This is also true in South Africa with its unique challenges and informal sector providing work to many South Africans not able to find work in the formal sector. Women operating in the corporate environment have traditionally encountered challenges in breaking through the glass ceiling in order to be counted as a successful person in her own right. The same scenario seems to be evident in the family Business environment. Women in family business might choose the family business career path as it allows them more flexibility and time to attend to the home and children, but they also face a glass ceiling of another nature and are there other challenges to overcome in order to make their mark in the family business world. This study’s primary objective was to investigate the literature pertaining to women in business and women in family business. Of great importance was to determine what contributions women make in the family business environment allowing them to be successful. In order to answer this question the secondary objectives supported the primary objective of this study and pertained to the difference between men and women in terms of leadership style and execution of their personalities in business. The inherent strengths and weaknesses displayed by both male and females in the family business environment are investigated in order to link this to their management execution. v A questionnaire was developed to do an empirical study on respondents as identified in the Nelson Mandela Metropole and greater Eastern Cape. The respondents were from varied industries and was selected and interviewed with the support of the questionnaire structure as guidance. The results were analysed and certain recommendations were made addressing the primary objective. Further recommendations were made relating to future potential research in this area. An important finding of the research is that women as identified in the Eastern Cape environment still have difficulty in reaching the top. This is true for the corporate world as well as the family business environment. The difficulty might be based in the traditional roles women assume, but in many cases it was found that women are responsible for their downfall or stagnation in the family business environment as women are satisfied to remain in the shadows and do not command their own space and right of existence. Recommendations were made based on the advice of some of the female respondents which can assist in women stepping up to the role they should take up. Some of the advice given can be used as a best practice in future research of this nature.
- Full Text:
- Date Issued: 2011
- Authors: Billson, Leonie
- Date: 2011
- Subjects: Family-owned business enterprises -- South Africa -- Eastern Cape , Businesswomen -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8585 , http://hdl.handle.net/10948/1608 , Family-owned business enterprises -- South Africa -- Eastern Cape , Businesswomen -- South Africa -- Eastern Cape
- Description: Family businesses are operating throughout the world and suggested to be the predominant way of doing business. This is also true in South Africa with its unique challenges and informal sector providing work to many South Africans not able to find work in the formal sector. Women operating in the corporate environment have traditionally encountered challenges in breaking through the glass ceiling in order to be counted as a successful person in her own right. The same scenario seems to be evident in the family Business environment. Women in family business might choose the family business career path as it allows them more flexibility and time to attend to the home and children, but they also face a glass ceiling of another nature and are there other challenges to overcome in order to make their mark in the family business world. This study’s primary objective was to investigate the literature pertaining to women in business and women in family business. Of great importance was to determine what contributions women make in the family business environment allowing them to be successful. In order to answer this question the secondary objectives supported the primary objective of this study and pertained to the difference between men and women in terms of leadership style and execution of their personalities in business. The inherent strengths and weaknesses displayed by both male and females in the family business environment are investigated in order to link this to their management execution. v A questionnaire was developed to do an empirical study on respondents as identified in the Nelson Mandela Metropole and greater Eastern Cape. The respondents were from varied industries and was selected and interviewed with the support of the questionnaire structure as guidance. The results were analysed and certain recommendations were made addressing the primary objective. Further recommendations were made relating to future potential research in this area. An important finding of the research is that women as identified in the Eastern Cape environment still have difficulty in reaching the top. This is true for the corporate world as well as the family business environment. The difficulty might be based in the traditional roles women assume, but in many cases it was found that women are responsible for their downfall or stagnation in the family business environment as women are satisfied to remain in the shadows and do not command their own space and right of existence. Recommendations were made based on the advice of some of the female respondents which can assist in women stepping up to the role they should take up. Some of the advice given can be used as a best practice in future research of this nature.
- Full Text:
- Date Issued: 2011
Molecular characterization, antibiograms and antibacterial activities of selected medicinal plants against some enteric pathogens
- Bisi-Johnson, Mary Adejumoke
- Authors: Bisi-Johnson, Mary Adejumoke
- Date: 2011
- Subjects: Diarrhea Diarrhea in children -- Complications Medicinal plants
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: vital:18475 , http://hdl.handle.net/11260/d1006643
- Description: Diarrhea diseases remain one of the greatest health problems in many parts of the world. In some cases, the disease is mild and self-limiting; however, the symptoms may be very severe in the elderly and young children (Smith and Cheasty, 1998), as well as in immune compromised patients such as HIV/AIDS patients. The disease is one of the hallmarks of HIV/AIDS in developing countries and is also a cardinal clinical manifestation of water borne infections (Obi et al., 2007). According to a World Health Organization report (WHO, 2004), diarrhea was rated second, after respiratory infections out of the eight deadliest diseases worldwide and was responsible for 1.8 million deaths per year. This infectious disease which can cause dehydration is primarily a symptom of gastrointestinal infection, but chemical irritation of the gut or non-infectious bowel disease can also result in diarrhoe. Studies have shown that the predominant causative agents of acute and persistent diarrhoe are Gram-negative rods such as Escherichia coli, Vibrio cholerae, Aeromonas, Campylobacter, Salmonella species, Shigella species, Plesiomonas shigelloides and Yersinia enterocolitica (Obi et al., 1995, 1998, 2003; Lainson and Silva, 1999; Coker et al., 2002; Oyofo et al., 2002). Aside from bacterial agents of diarrhoea, other causative pathogens include protozoa such as Giardia lamblia and Cryptosporidium parvum; viruses such as norwalk virus and rota virus. Although fungal agents such as Candida have been shown to be prevalent in children with diarrhoe (Enweani et al. 1994), a more recent study (Forbes et al., 2001), associated higher Candida counts with recent antibiotic use. Faecal concentrations of Candida were higher in patients with diarrhoe, but the study confirmed no association between faecal candida or other yeasts and diarrhoe. Norwalk viruses, calci-like viruses and rota viruses are the major viral agents of diarrhoe. According to Parashar et al., (2006), rota virus is the leading cause of diarrhoe hospitalisation among children worldwide, causing 440,000 annual deaths in children under 5 years of age.
- Full Text:
- Date Issued: 2011
- Authors: Bisi-Johnson, Mary Adejumoke
- Date: 2011
- Subjects: Diarrhea Diarrhea in children -- Complications Medicinal plants
- Language: English
- Type: Thesis , Doctoral , Ph D
- Identifier: vital:18475 , http://hdl.handle.net/11260/d1006643
- Description: Diarrhea diseases remain one of the greatest health problems in many parts of the world. In some cases, the disease is mild and self-limiting; however, the symptoms may be very severe in the elderly and young children (Smith and Cheasty, 1998), as well as in immune compromised patients such as HIV/AIDS patients. The disease is one of the hallmarks of HIV/AIDS in developing countries and is also a cardinal clinical manifestation of water borne infections (Obi et al., 2007). According to a World Health Organization report (WHO, 2004), diarrhea was rated second, after respiratory infections out of the eight deadliest diseases worldwide and was responsible for 1.8 million deaths per year. This infectious disease which can cause dehydration is primarily a symptom of gastrointestinal infection, but chemical irritation of the gut or non-infectious bowel disease can also result in diarrhoe. Studies have shown that the predominant causative agents of acute and persistent diarrhoe are Gram-negative rods such as Escherichia coli, Vibrio cholerae, Aeromonas, Campylobacter, Salmonella species, Shigella species, Plesiomonas shigelloides and Yersinia enterocolitica (Obi et al., 1995, 1998, 2003; Lainson and Silva, 1999; Coker et al., 2002; Oyofo et al., 2002). Aside from bacterial agents of diarrhoea, other causative pathogens include protozoa such as Giardia lamblia and Cryptosporidium parvum; viruses such as norwalk virus and rota virus. Although fungal agents such as Candida have been shown to be prevalent in children with diarrhoe (Enweani et al. 1994), a more recent study (Forbes et al., 2001), associated higher Candida counts with recent antibiotic use. Faecal concentrations of Candida were higher in patients with diarrhoe, but the study confirmed no association between faecal candida or other yeasts and diarrhoe. Norwalk viruses, calci-like viruses and rota viruses are the major viral agents of diarrhoe. According to Parashar et al., (2006), rota virus is the leading cause of diarrhoe hospitalisation among children worldwide, causing 440,000 annual deaths in children under 5 years of age.
- Full Text:
- Date Issued: 2011
Do budget deficits crowd out private investment?: an analysis of the South African Economy
- Authors: Biza, Rumbidzai Aimee
- Date: 2011
- Subjects: Individual investors -- South Africa , Budget deficits -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24956 , vital:63750
- Description: This dissertation investigates whether budget deficits crowd out or crowd in private investment in South Africa, using quarterly South African data covering the period 1994 to 2009. South Africa has been experiencing unprecedented budget deficits since the 1960s and the study investigates how this has impacted on the country’s private investment demand. An empirical model linking private investment to its theoretical variables is specified and used to assess the quantitative effects of budget deficits on private investment. This study augments the co-integration and vector auto-regression (VAR) analysis with impulse response and variance decomposition analyses to provide robust long run and short run dynamic effects on private investment. The variables have been found to have a long run relationship with private investment. Results suggest that budget deficits significantly crowds out private investment. These results corroborate the theoretical predictions and are also supported by previous studies. , Thesis (MCom) -- Faculty of Management and Commerce, 2011
- Full Text:
- Date Issued: 2011
- Authors: Biza, Rumbidzai Aimee
- Date: 2011
- Subjects: Individual investors -- South Africa , Budget deficits -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24956 , vital:63750
- Description: This dissertation investigates whether budget deficits crowd out or crowd in private investment in South Africa, using quarterly South African data covering the period 1994 to 2009. South Africa has been experiencing unprecedented budget deficits since the 1960s and the study investigates how this has impacted on the country’s private investment demand. An empirical model linking private investment to its theoretical variables is specified and used to assess the quantitative effects of budget deficits on private investment. This study augments the co-integration and vector auto-regression (VAR) analysis with impulse response and variance decomposition analyses to provide robust long run and short run dynamic effects on private investment. The variables have been found to have a long run relationship with private investment. Results suggest that budget deficits significantly crowds out private investment. These results corroborate the theoretical predictions and are also supported by previous studies. , Thesis (MCom) -- Faculty of Management and Commerce, 2011
- Full Text:
- Date Issued: 2011
Ericoid mycorrhizal fungi and potential for inoculation of commercial berry species (Vaccinium corymbosium L.)
- Authors: Bizabani, Christine
- Date: 2011
- Subjects: Ericaceae , Mycorrhizas , Fynbos
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4136 , http://hdl.handle.net/10962/d1016127
- Description: Ericaceous plants are the richest growth form of the fynbos vegetation of South Africa. The fynbos is characterized by highly leached acidic soils, low mineral nutrients and climatically it is a winter rainfall and dry summer region. Ericoid mycorrhizal fungi associate with Erica species enhancing their ability to access essential nutrients for survival under unfavourable growth conditions. The aim of this study was to select local Ericaceae plant species and to isolate, identify and characterize the ericoid endophytes and assess these isolates as potential inocula for commercial berry species. Two ericaceous plants Erica cerinthoides L. and Erica demmissa Klotzsch ex Benth. were identified from the Mountain Drive area of Grahamstown, Eastern Cape. Root staining was used to confirm the mycorrhizal status of both plants. Hyphal coils typical of ericoid association were observed within the epidermal cells of the hair roots under a light microscope. The endophytes were successfully isolated in pure culture on 2% malt extract agar (MEA) and modified Fontana medium. Cultural morphology and microscopy were used for initial identification. Two slow growing isolates were selected. These isolates were further subjected to molecular identification; extracted DNA was amplified using ITS1 and ITS4 fungal primers. The rDNA gene internal transcriber spacer (ITS) was then sequenced and analyzed by comparison to sequences in the GenBank. On the basis of percentage sequence identity Lachnum Retz. species and Cadophora Lagerb. & Melin species were identified as the ericoid endophytes of E. cerinthoides and E. demmissa respectively. The optimum growth parameters of the fungal isolates were determined in 2% MEA incubated at varying temperatures and pH. It was established that both species had optimum growth at 27⁰C and pH 5. The Ericaceae species are sometimes found in metal contaminated sites were ericoid fungi have been proved to alleviate toxicity of their host. The fungal isolates were grown in increasing concentration of Cu²⁺ and Zn²⁺ in 2% MEA. The growth of Lachnum species decreased with increasing Zn²⁺ ions above 2.7 mM while Cadophora species showed a change in morphology and also decreased in growth with increased ion concentration. However there were no significant differences recorded in the growth of Cadophora and Lachnum species on increasing Cu²⁺ concentration. Lachnum and Cadophora isolates were formulated into a semi solid inoculum and inoculated onto micropropagated Vaccinni corymbosum L. plantlets of 5 different varieties. Colonization was low for all varieties, Elliott and Brightwell varieties recorded the highest colonization of 35% and 31% respectively. Lachnum species infected roots showed potential ericoid structures while the Cadophora inoculated plantlets had hyphal coils within the cortical cells typical of ericoid mycorrhizas. Inoculation significantly enhanced the shoot growth of Brightwell and Elliott varieties. The Chandler variety inoculated with Lachnum species showed improved shoot dry weight. The Bluecrop and Elliott varieties inoculated with Cadophora and Lachnum accumulated more root biomass. All inoculated Bluecrop plantlets had an improved canopy growth index. Brightwell plantlets inoculated with Lachnum species also had an enhanced canopy growth index. The growth responses were variable within varieties and between varieties. Treatments with the Cadophora and Lachnum have shown potential in the promotion of growth of the Blueberry species. The findings indicate the need to conduct trials under conditions which simulate the commercial growth conditions so as explore the optimum potential of the isolates.
- Full Text:
- Date Issued: 2011
- Authors: Bizabani, Christine
- Date: 2011
- Subjects: Ericaceae , Mycorrhizas , Fynbos
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4136 , http://hdl.handle.net/10962/d1016127
- Description: Ericaceous plants are the richest growth form of the fynbos vegetation of South Africa. The fynbos is characterized by highly leached acidic soils, low mineral nutrients and climatically it is a winter rainfall and dry summer region. Ericoid mycorrhizal fungi associate with Erica species enhancing their ability to access essential nutrients for survival under unfavourable growth conditions. The aim of this study was to select local Ericaceae plant species and to isolate, identify and characterize the ericoid endophytes and assess these isolates as potential inocula for commercial berry species. Two ericaceous plants Erica cerinthoides L. and Erica demmissa Klotzsch ex Benth. were identified from the Mountain Drive area of Grahamstown, Eastern Cape. Root staining was used to confirm the mycorrhizal status of both plants. Hyphal coils typical of ericoid association were observed within the epidermal cells of the hair roots under a light microscope. The endophytes were successfully isolated in pure culture on 2% malt extract agar (MEA) and modified Fontana medium. Cultural morphology and microscopy were used for initial identification. Two slow growing isolates were selected. These isolates were further subjected to molecular identification; extracted DNA was amplified using ITS1 and ITS4 fungal primers. The rDNA gene internal transcriber spacer (ITS) was then sequenced and analyzed by comparison to sequences in the GenBank. On the basis of percentage sequence identity Lachnum Retz. species and Cadophora Lagerb. & Melin species were identified as the ericoid endophytes of E. cerinthoides and E. demmissa respectively. The optimum growth parameters of the fungal isolates were determined in 2% MEA incubated at varying temperatures and pH. It was established that both species had optimum growth at 27⁰C and pH 5. The Ericaceae species are sometimes found in metal contaminated sites were ericoid fungi have been proved to alleviate toxicity of their host. The fungal isolates were grown in increasing concentration of Cu²⁺ and Zn²⁺ in 2% MEA. The growth of Lachnum species decreased with increasing Zn²⁺ ions above 2.7 mM while Cadophora species showed a change in morphology and also decreased in growth with increased ion concentration. However there were no significant differences recorded in the growth of Cadophora and Lachnum species on increasing Cu²⁺ concentration. Lachnum and Cadophora isolates were formulated into a semi solid inoculum and inoculated onto micropropagated Vaccinni corymbosum L. plantlets of 5 different varieties. Colonization was low for all varieties, Elliott and Brightwell varieties recorded the highest colonization of 35% and 31% respectively. Lachnum species infected roots showed potential ericoid structures while the Cadophora inoculated plantlets had hyphal coils within the cortical cells typical of ericoid mycorrhizas. Inoculation significantly enhanced the shoot growth of Brightwell and Elliott varieties. The Chandler variety inoculated with Lachnum species showed improved shoot dry weight. The Bluecrop and Elliott varieties inoculated with Cadophora and Lachnum accumulated more root biomass. All inoculated Bluecrop plantlets had an improved canopy growth index. Brightwell plantlets inoculated with Lachnum species also had an enhanced canopy growth index. The growth responses were variable within varieties and between varieties. Treatments with the Cadophora and Lachnum have shown potential in the promotion of growth of the Blueberry species. The findings indicate the need to conduct trials under conditions which simulate the commercial growth conditions so as explore the optimum potential of the isolates.
- Full Text:
- Date Issued: 2011
Coping strategies among female Zimbabwean refugees at the central Methodist church in Johannesburg : a conflict management perspective
- Authors: Bjorknes, Guro Lauvland
- Date: 2011
- Subjects: Central Methodist Church Refugee Community , Church work with refugees , Conflict management , Interpersonal relations
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8188 , http://hdl.handle.net/10948/1424 , Central Methodist Church Refugee Community , Church work with refugees , Conflict management , Interpersonal relations
- Description: This treatise represents an investigation into the coping strategies of female Zimbabwean refugees at the Central Methodist Church (CMC) in Johannesburg. The CMC in Johannesburg includes a non-profit organisation called Ray of Hope that has functioned as a provider of accommodation and emergency refuge at the church since 1997. A vast number of Zimbabweans are moving to adjacent countries as a consequence of the conflict in Zimbabwe and approximately 85 percent of the people that have sought refuge in the CMC in Johannesburg are Zimbabweans that have fled the economic and political conflict in Zimbabwe. Using an interviewing strategy of a sample of 20 female Zimbabwean refugees, conducted at the CMC, the researcher gathered data, indicating that they face various conflicts on a daily basis inside as well as outside the refugee community in the CMC in Johannesburg. An extensive literature review and researcher‟s own observations during hours spent in the refugee community have also contributed to the collection of data. The findings suggest that coping mechanisms have been adopted by the female refugees to deal with the conflicts. Analysis of data was guided by grounded theory approach which allowed key findings about coping mechanisms to surface which encouraged recommendations presented in the conclusion of the treatise.
- Full Text:
- Date Issued: 2011
- Authors: Bjorknes, Guro Lauvland
- Date: 2011
- Subjects: Central Methodist Church Refugee Community , Church work with refugees , Conflict management , Interpersonal relations
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: vital:8188 , http://hdl.handle.net/10948/1424 , Central Methodist Church Refugee Community , Church work with refugees , Conflict management , Interpersonal relations
- Description: This treatise represents an investigation into the coping strategies of female Zimbabwean refugees at the Central Methodist Church (CMC) in Johannesburg. The CMC in Johannesburg includes a non-profit organisation called Ray of Hope that has functioned as a provider of accommodation and emergency refuge at the church since 1997. A vast number of Zimbabweans are moving to adjacent countries as a consequence of the conflict in Zimbabwe and approximately 85 percent of the people that have sought refuge in the CMC in Johannesburg are Zimbabweans that have fled the economic and political conflict in Zimbabwe. Using an interviewing strategy of a sample of 20 female Zimbabwean refugees, conducted at the CMC, the researcher gathered data, indicating that they face various conflicts on a daily basis inside as well as outside the refugee community in the CMC in Johannesburg. An extensive literature review and researcher‟s own observations during hours spent in the refugee community have also contributed to the collection of data. The findings suggest that coping mechanisms have been adopted by the female refugees to deal with the conflicts. Analysis of data was guided by grounded theory approach which allowed key findings about coping mechanisms to surface which encouraged recommendations presented in the conclusion of the treatise.
- Full Text:
- Date Issued: 2011
The impact of delivery performance for a selected part of General Motors South Africa (GMSA)
- Authors: Blouw, Andrew Christopher
- Date: 2011
- Subjects: General Motors Corporation , Automobiles -- Parts -- South Africa -- Eastern Cape , Management -- South Africa -- Eastern Cape , Motor industry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8793 , http://hdl.handle.net/10948/d1015957
- Description: Today‘s customers expect zero defects with just-in-time (JIT) delivery from their suppliers, for the specified quantities, as a matter of standard practice. More importantly, customers expect companies to help them know what they need in terms of quantities and quality now, and for the future. No other change process adds long-term value as quickly as zero defects. Companies failing to embrace this quality culture face difficult challenges. To achieve this level of performance requires tremendous focus in an organisation and throughout its supply base. Business models around the world are changing dramatically from the "Source Local" to the "Source Anywhere and Build Anywhere" model (Cummins, 2008: 19). Companies have shifted away from a hierarchical, one-dimensional, supply chain entity to a fragmented network in favor of strategic partnerships with external entities. Many businesses facing such models are experiencing challenges and, if not managed correctly, can find themselves struggling to compete in this new landscape. Thus, when price concessions are so stringent, quality has to suffer. To reduce costs, suppliers are forced to seek less expensive ways to produce parts and components. Does this mean the use of different, less expensive materials? Does this mean less skilled labor? Does this mean production shortcuts? Or does this mean that suppliers just bite the bullet and pay the price? Once all the costs have been extracted from the supply chain, the only thing left to suffer is quality. The underlying objective of this research is to investigate the impact of delivery performance for a selected part at General Motors South Africa. In order to develop a research strategy to deal with, and solve, the main problem, the following research questions have been identified: a) What can be learned from literature about the impact of quality costs? b) Why is this specific part a suitable candidate for a cost investigation? c) What are the processes involved if a defect occurs? d) How can the cost be estimated? e) What effect does poor supplier quality have on productivity? This dissertation aims to investigate the problems and challenges General Motors South Africa are facing pertaining to the delivery performance of a selected part. The dissertation will also strive to highlight the impact of poor supplier quality on productivity and the related cost implications. Conclusions and recommendations will furthermore be outlined.
- Full Text:
- Date Issued: 2011
- Authors: Blouw, Andrew Christopher
- Date: 2011
- Subjects: General Motors Corporation , Automobiles -- Parts -- South Africa -- Eastern Cape , Management -- South Africa -- Eastern Cape , Motor industry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8793 , http://hdl.handle.net/10948/d1015957
- Description: Today‘s customers expect zero defects with just-in-time (JIT) delivery from their suppliers, for the specified quantities, as a matter of standard practice. More importantly, customers expect companies to help them know what they need in terms of quantities and quality now, and for the future. No other change process adds long-term value as quickly as zero defects. Companies failing to embrace this quality culture face difficult challenges. To achieve this level of performance requires tremendous focus in an organisation and throughout its supply base. Business models around the world are changing dramatically from the "Source Local" to the "Source Anywhere and Build Anywhere" model (Cummins, 2008: 19). Companies have shifted away from a hierarchical, one-dimensional, supply chain entity to a fragmented network in favor of strategic partnerships with external entities. Many businesses facing such models are experiencing challenges and, if not managed correctly, can find themselves struggling to compete in this new landscape. Thus, when price concessions are so stringent, quality has to suffer. To reduce costs, suppliers are forced to seek less expensive ways to produce parts and components. Does this mean the use of different, less expensive materials? Does this mean less skilled labor? Does this mean production shortcuts? Or does this mean that suppliers just bite the bullet and pay the price? Once all the costs have been extracted from the supply chain, the only thing left to suffer is quality. The underlying objective of this research is to investigate the impact of delivery performance for a selected part at General Motors South Africa. In order to develop a research strategy to deal with, and solve, the main problem, the following research questions have been identified: a) What can be learned from literature about the impact of quality costs? b) Why is this specific part a suitable candidate for a cost investigation? c) What are the processes involved if a defect occurs? d) How can the cost be estimated? e) What effect does poor supplier quality have on productivity? This dissertation aims to investigate the problems and challenges General Motors South Africa are facing pertaining to the delivery performance of a selected part. The dissertation will also strive to highlight the impact of poor supplier quality on productivity and the related cost implications. Conclusions and recommendations will furthermore be outlined.
- Full Text:
- Date Issued: 2011
Remuneration and rewards strategies at the Nelson Mandela Metropolitan University
- Authors: Bobi, Lungiswa
- Date: 2011
- Subjects: Nelson Mandela Metropolitan University , Compensation management -- South Africa , Employee retention -- South Africa -- Port Elizabeth , Incentives in industry , Employee motivation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9393 , http://hdl.handle.net/10948/d1021232
- Description: To be competitive, organisations need to ensure that all their resources are functioning at optimal level. The most important of these resources being its employees. This is because their commitment can guarantee the attainment of organisational goals. Commitment can be attained by an organisation through the payment of internally and externally competitive remuneration and reward packages, that communicate the value of the employees to the organisation. Remuneration and reward strategies are a critical tool for organisations, as they can motivate, attract and retain high performing employees. The theories of motivation, such as, the equity theory, state that employees compare their compensation with that of others and that if they perceive inequity, can be de-motivated or leave an organisation. Therefore, it is imperative for an organisation to ensure that its remuneration and reward strategy is aligned with its business strategy, to ensure clear communication of goals. In order to prevent labour turnover and to ensure commitment and retention, the employer needs to offer total rewards, which include base pay, benefits, variable performance pay, recognition and an enabling work environment. These can be effective as they meet all employee needs as in Maslow‟s hierarchy of needs and ensure the satisfaction of the organisation‟s need for goal attainment. To gain more insight, an empirical study was conducted at the Nelson Mandela Metropolitan University. The results of the survey indicated that the NMMU‟s remuneration and reward strategy contained certain elements of the total rewards strategy. These are variable pay in the form of a service bonus and benefits plus based pay. This strategy seems to be ineffective to motivate and retain employees due to lack of clear communication and recognition. To motivate and retain its employees, the NMMU should improve its communication and engage employees and unions in defining remuneration and reward strategies through collaboration.
- Full Text:
- Date Issued: 2011
- Authors: Bobi, Lungiswa
- Date: 2011
- Subjects: Nelson Mandela Metropolitan University , Compensation management -- South Africa , Employee retention -- South Africa -- Port Elizabeth , Incentives in industry , Employee motivation
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9393 , http://hdl.handle.net/10948/d1021232
- Description: To be competitive, organisations need to ensure that all their resources are functioning at optimal level. The most important of these resources being its employees. This is because their commitment can guarantee the attainment of organisational goals. Commitment can be attained by an organisation through the payment of internally and externally competitive remuneration and reward packages, that communicate the value of the employees to the organisation. Remuneration and reward strategies are a critical tool for organisations, as they can motivate, attract and retain high performing employees. The theories of motivation, such as, the equity theory, state that employees compare their compensation with that of others and that if they perceive inequity, can be de-motivated or leave an organisation. Therefore, it is imperative for an organisation to ensure that its remuneration and reward strategy is aligned with its business strategy, to ensure clear communication of goals. In order to prevent labour turnover and to ensure commitment and retention, the employer needs to offer total rewards, which include base pay, benefits, variable performance pay, recognition and an enabling work environment. These can be effective as they meet all employee needs as in Maslow‟s hierarchy of needs and ensure the satisfaction of the organisation‟s need for goal attainment. To gain more insight, an empirical study was conducted at the Nelson Mandela Metropolitan University. The results of the survey indicated that the NMMU‟s remuneration and reward strategy contained certain elements of the total rewards strategy. These are variable pay in the form of a service bonus and benefits plus based pay. This strategy seems to be ineffective to motivate and retain employees due to lack of clear communication and recognition. To motivate and retain its employees, the NMMU should improve its communication and engage employees and unions in defining remuneration and reward strategies through collaboration.
- Full Text:
- Date Issued: 2011
A theoretical study on the Alexander technique for the organ
- Authors: Boonzaaier, Devandre
- Date: 2011
- Subjects: Musicians -- Health and hygiene , Alexander technique , Organ (Musical instrument) -- Instruction and study , Organists -- Training of -- South Africa , Music -- Performance -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8520 , http://hdl.handle.net/10948/d1015727
- Description: The aim of this research is to provide a theoretical framework of the Alexander Technique for organists. Frederick Matthias Alexander was an Australian actor who developed a technique to enable and enhance his own performance. This innovative technique is now used across the world, including South Africa. In this study the researcher provides a Literature Study of the Alexander Technique. Furthermore, he investigates and reports on the practises of a number of organists. A multiple case study approach was adapted and data was collected by means of questionnaires, personal observations and informal interviews. The data gathered in this study is described and analysed. The study culminates with a description of a theoretical framework for the application of the Alexander Technique for organists.
- Full Text:
- Date Issued: 2011
- Authors: Boonzaaier, Devandre
- Date: 2011
- Subjects: Musicians -- Health and hygiene , Alexander technique , Organ (Musical instrument) -- Instruction and study , Organists -- Training of -- South Africa , Music -- Performance -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8520 , http://hdl.handle.net/10948/d1015727
- Description: The aim of this research is to provide a theoretical framework of the Alexander Technique for organists. Frederick Matthias Alexander was an Australian actor who developed a technique to enable and enhance his own performance. This innovative technique is now used across the world, including South Africa. In this study the researcher provides a Literature Study of the Alexander Technique. Furthermore, he investigates and reports on the practises of a number of organists. A multiple case study approach was adapted and data was collected by means of questionnaires, personal observations and informal interviews. The data gathered in this study is described and analysed. The study culminates with a description of a theoretical framework for the application of the Alexander Technique for organists.
- Full Text:
- Date Issued: 2011
Age validation, growth, mortality, and demographic modeling of spotted gully shark (Triakis megalopterus) from the southeast coast of South Africa
- Booth, Anthony J, Foulis, Alan J, Smale, Malcolm J
- Authors: Booth, Anthony J , Foulis, Alan J , Smale, Malcolm J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123630 , vital:35466 , https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/2011/1091/booth.pdf
- Description: This study documents validation of vertebral band-pair formation in spotted gully shark (Triakis megalopterus) with the use of f luorochrome injection and tagging of captive and wild sharks over a 21-year period. Growth and mortality rates of T. megalopterus were also estimated and a demographic analysis of the species was conducted. Of the 23 OTC (oxytetracycline) -marked vertebrae examined (12 from captive and 11 from wild sharks), seven vertebrae (three from captive and four from wild sharks) exhibited chelation of the OTC and f luoresced under ultraviolet light. It was concluded that a single opaque and translucent band pair was deposited annually up to at least 25 years of age, the maximum age recorded. Reader precision was assessed by using an index of average percent error calculated at 5%. No significant differences were found between male and female growth patterns (P>0.05), and von Bertalanffy growth model parameters for combined sexes were estimated to be L∞=1711.07 mm TL, k=0.11/yr and t0= –2.43 yr (n=86). Natural mortality was estimated at 0.17/yr. Age at maturity was estimated at 11 years for males and 15 years for females. Results of the demographic analysis showed that the population, in the absence of fishing mortality, was stable and not significantly different from zero and particularly sensitive to overfishing. At the current age at first capture and natural mortality rate, the fishing mortality rate required to result in negative population growth was low at F>0.004/ yr. Elasticity analysis revealed that juvenile survival was the principal factor in explaining variability in population growth rate.
- Full Text:
- Date Issued: 2011
- Authors: Booth, Anthony J , Foulis, Alan J , Smale, Malcolm J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123630 , vital:35466 , https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/2011/1091/booth.pdf
- Description: This study documents validation of vertebral band-pair formation in spotted gully shark (Triakis megalopterus) with the use of f luorochrome injection and tagging of captive and wild sharks over a 21-year period. Growth and mortality rates of T. megalopterus were also estimated and a demographic analysis of the species was conducted. Of the 23 OTC (oxytetracycline) -marked vertebrae examined (12 from captive and 11 from wild sharks), seven vertebrae (three from captive and four from wild sharks) exhibited chelation of the OTC and f luoresced under ultraviolet light. It was concluded that a single opaque and translucent band pair was deposited annually up to at least 25 years of age, the maximum age recorded. Reader precision was assessed by using an index of average percent error calculated at 5%. No significant differences were found between male and female growth patterns (P>0.05), and von Bertalanffy growth model parameters for combined sexes were estimated to be L∞=1711.07 mm TL, k=0.11/yr and t0= –2.43 yr (n=86). Natural mortality was estimated at 0.17/yr. Age at maturity was estimated at 11 years for males and 15 years for females. Results of the demographic analysis showed that the population, in the absence of fishing mortality, was stable and not significantly different from zero and particularly sensitive to overfishing. At the current age at first capture and natural mortality rate, the fishing mortality rate required to result in negative population growth was low at F>0.004/ yr. Elasticity analysis revealed that juvenile survival was the principal factor in explaining variability in population growth rate.
- Full Text:
- Date Issued: 2011
Syntheses and electrochemical characterization of new water soluble octaarylthiosubstituted manganese phthalocyanines
- Booysen, Irvin N, Matemadombo, Fungisai, Durmus, Mahmut, Nyokong, Tebello
- Authors: Booysen, Irvin N , Matemadombo, Fungisai , Durmus, Mahmut , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247614 , vital:51600 , xlink:href="https://doi.org/10.1016/j.dyepig.2010.09.012"
- Description: This paper reports on the synthesis and characterization of new manganese phthalocyanine (MnPc) complexes: 2,3-octakis-[(2-mercaptopyridine) phthalocyaninato] acetato manganese (III) (1) and its quaternized (hence water soluble) derivative: 2,3-octakis-{[(N-methyl-2-mercaptopyridine) phthalocyaninato] acetato manganese (III)} sulphate (2). The complexes were used to form self assembled monolayers (SAMs). Voltammetry proved that both of the SAMs are well packed, strongly passivating and act as selective and efficient barriers to ion permeability. Furthermore, surface coverage studies confirmed that the MPc macrocycles adsorb onto the gold electrode as monolayers. Both MPc SAMs were successfully used as electrochemical sensors of nitrite.
- Full Text:
- Date Issued: 2011
- Authors: Booysen, Irvin N , Matemadombo, Fungisai , Durmus, Mahmut , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247614 , vital:51600 , xlink:href="https://doi.org/10.1016/j.dyepig.2010.09.012"
- Description: This paper reports on the synthesis and characterization of new manganese phthalocyanine (MnPc) complexes: 2,3-octakis-[(2-mercaptopyridine) phthalocyaninato] acetato manganese (III) (1) and its quaternized (hence water soluble) derivative: 2,3-octakis-{[(N-methyl-2-mercaptopyridine) phthalocyaninato] acetato manganese (III)} sulphate (2). The complexes were used to form self assembled monolayers (SAMs). Voltammetry proved that both of the SAMs are well packed, strongly passivating and act as selective and efficient barriers to ion permeability. Furthermore, surface coverage studies confirmed that the MPc macrocycles adsorb onto the gold electrode as monolayers. Both MPc SAMs were successfully used as electrochemical sensors of nitrite.
- Full Text:
- Date Issued: 2011
Bollywood Nights: Indian youth and the creation of diasporic identity in South Africa
- Authors: Boshoff, Priscilla A
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143494 , vital:38251 , DOI: 10.3138/topia.26.29
- Description: Bollywood’s popularity as a global cultural form has occurred at the same time as the valorization of difference in the South African political landscape. As the youngest members of the 19th-century labour diaspora, South African Indian youths are the inheritors of a conservative—yet adaptable—home culture amidst the marginalized identities of (post-)apartheid South Africa. Their desire to create an identity for themselves that encompasses their self-perception both as modern South African subjects and as guardians of their traditional home cultures is achieved through Bollywood, which speaks to its diasporic audiences through images of an idealized traditional yet modern India. While India is not a place of return for these youth, their reactivation of a diasporic identity through Bollywood’s representations of a successful Indian diasporic culture and their participation in South African Bollywood concerts and award ceremonies has provided an opportunity for young South African Indians to reimagine their diasporic Indian identity in ways that (re-)connect them to India and to an imagined global diaspora.
- Full Text:
- Date Issued: 2018
- Authors: Boshoff, Priscilla A
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143494 , vital:38251 , DOI: 10.3138/topia.26.29
- Description: Bollywood’s popularity as a global cultural form has occurred at the same time as the valorization of difference in the South African political landscape. As the youngest members of the 19th-century labour diaspora, South African Indian youths are the inheritors of a conservative—yet adaptable—home culture amidst the marginalized identities of (post-)apartheid South Africa. Their desire to create an identity for themselves that encompasses their self-perception both as modern South African subjects and as guardians of their traditional home cultures is achieved through Bollywood, which speaks to its diasporic audiences through images of an idealized traditional yet modern India. While India is not a place of return for these youth, their reactivation of a diasporic identity through Bollywood’s representations of a successful Indian diasporic culture and their participation in South African Bollywood concerts and award ceremonies has provided an opportunity for young South African Indians to reimagine their diasporic Indian identity in ways that (re-)connect them to India and to an imagined global diaspora.
- Full Text:
- Date Issued: 2018