The rights of employees following a transfer of an undertaking in terms of section 197 of the Labour Relation Act in an outsourcing context
- Authors: Crouse, Chantell Belinda
- Date: 2012
- Subjects: Employee rights , Employees -- Transfer -- Law and legislation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10241 , http://hdl.handle.net/10948/d1015060
- Description: The protection that employees enjoy under our common law in the transfer of a business of its employer is very little. Common law only concerns itself with the lawfulness of a contract of employment. Common law is, however, now also experiencing the effect of the Constitution which provides for fair labour practices. Proper legislation was enacted to afford employees proper protection against dismissals resulting out of a transfer of a business by the employer as a going concern. Such a dismissal would be automatically unfair in terms of section 187(1)(g) of the LRA. The protection that employees enjoy is governed by section 197 of the LRA. This section provides that the new employer is placed in the “shoes” of the old employer. It also further states that the new employer could be held accountable for the unlawful actions of the old employer against an employee prior to the transfer taking place. Section 197 of the LRA, however, does not apply to all transfers of businesses. There are some key concepts that are of importance to determine its applicability. Such concepts include whether there was a transfer of a business or a part of the business and whether it was transferred as a going concern. The words “transfer” and “business” are defined in section 197(1)(a) and (1)(b) of the LRA. However, the words “going concern” are not defined and one would have to scrutinise case law for guidance in considering whether the transfer was done as a going concern. A leading case is that of Schutte Powerplus Performance (Pty) Ltd.1 In this case the court held that one must consider the substance of the agreement in determining whether the business was transferred as a going concern. It further held that the lists of factors that one should have regard to are not exhaustive. Section 197 of the LRA also applies to employees whose services have been outsourced. Outsourcing of services occurs where an employer discontinues a service or activity that is in most cases not part of the main business of the employer, and contract an outside contractor to take over that service or activity. This matter was given clarity in the case of SA Municipal Workers Union v Rand Airport Management Company (Pty) Ltd.2 The court came to the conclusion that section 197 could apply to outsourcing, provided it passes the test of “transfer” as well as the test of what constitutes a “business or service”. Outsourcing to labour brokers is, however, not covered by section 197 of the LRA. The matter was given consideration by the Labour Court in CEPPWAWU v Print Tech (Pty) Ltd.3 Another question is whether second-generation outsourcing is covered by section 197 of the LRA. Second Generation Outsourcing occurs when an employer put the outsourced service out to tender upon the outsource contract coming to an end and a new entity is awarded the outsourcing opportunity following the original outsource entity being unsuccessful in its bid to secure the contract for an additional term.
- Full Text:
- Date Issued: 2012
- Authors: Crouse, Chantell Belinda
- Date: 2012
- Subjects: Employee rights , Employees -- Transfer -- Law and legislation
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10241 , http://hdl.handle.net/10948/d1015060
- Description: The protection that employees enjoy under our common law in the transfer of a business of its employer is very little. Common law only concerns itself with the lawfulness of a contract of employment. Common law is, however, now also experiencing the effect of the Constitution which provides for fair labour practices. Proper legislation was enacted to afford employees proper protection against dismissals resulting out of a transfer of a business by the employer as a going concern. Such a dismissal would be automatically unfair in terms of section 187(1)(g) of the LRA. The protection that employees enjoy is governed by section 197 of the LRA. This section provides that the new employer is placed in the “shoes” of the old employer. It also further states that the new employer could be held accountable for the unlawful actions of the old employer against an employee prior to the transfer taking place. Section 197 of the LRA, however, does not apply to all transfers of businesses. There are some key concepts that are of importance to determine its applicability. Such concepts include whether there was a transfer of a business or a part of the business and whether it was transferred as a going concern. The words “transfer” and “business” are defined in section 197(1)(a) and (1)(b) of the LRA. However, the words “going concern” are not defined and one would have to scrutinise case law for guidance in considering whether the transfer was done as a going concern. A leading case is that of Schutte Powerplus Performance (Pty) Ltd.1 In this case the court held that one must consider the substance of the agreement in determining whether the business was transferred as a going concern. It further held that the lists of factors that one should have regard to are not exhaustive. Section 197 of the LRA also applies to employees whose services have been outsourced. Outsourcing of services occurs where an employer discontinues a service or activity that is in most cases not part of the main business of the employer, and contract an outside contractor to take over that service or activity. This matter was given clarity in the case of SA Municipal Workers Union v Rand Airport Management Company (Pty) Ltd.2 The court came to the conclusion that section 197 could apply to outsourcing, provided it passes the test of “transfer” as well as the test of what constitutes a “business or service”. Outsourcing to labour brokers is, however, not covered by section 197 of the LRA. The matter was given consideration by the Labour Court in CEPPWAWU v Print Tech (Pty) Ltd.3 Another question is whether second-generation outsourcing is covered by section 197 of the LRA. Second Generation Outsourcing occurs when an employer put the outsourced service out to tender upon the outsource contract coming to an end and a new entity is awarded the outsourcing opportunity following the original outsource entity being unsuccessful in its bid to secure the contract for an additional term.
- Full Text:
- Date Issued: 2012
Characterization of cell mismatch in photovoltaic modules using electroluminescence and associated electro-optic techniques
- Authors: Crozier, Jacqueline Louise
- Date: 2012
- Subjects: Photovoltaic cells , Solar cells
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10545 , http://hdl.handle.net/10948/d1015059
- Description: Solar cells allow the energy from the sun to be converted into electrical energy; this makes solar energy much more environmentally friendly than fossil fuel energy sources. These solar cells are connected together in a photovoltaic (PV) module to provide the higher current, voltage and power outputs necessary for electrical applications. However, the performance of the PV module is limited by the performance of the individual cells. Cell mismatch occurs when some cells are damaged or shaded and produce lower current output than the other cells in the series connected string. The cell mismatch lowers the module performance and can result in further damage as the weak cells are reverse biased and dissipate heat. Bypass diodes can be connected into the module to increase the module current output and prevent further damage. Since cell mismatch results in a significant decrease in the performance of deployed modules it is important to fully understand and characterise its effect on PV modules. PV modules can be characterised using various techniques, each providing important information about the performance of the module. Most commonly the current-voltage (I-V) characteristic curve of a module is measured in outdoor, fully illuminated conditions. This allows performance parameters such as short circuit current (Isc), open circuit voltage (Voc) and maximum power (Pmax) to be determined. In addition to this the shape of the curve allows device parameters like series and shunt resistances to be determined using parameter extraction algorithms like Particle Swarm Optimisation (PSO). The extracted parameters can be entered into the diode equation to model the I-V curve of the module. The I-V characteristic of the module can also be used to identify poor current producing cells in the module by using the worst-case cell determination method. In this technique a cell is shaded and the greater the drop in current in the whole module the better the current production of the shaded cell. The photoresponse of cells in a module can be determined by the Large-area Light Beam Induced Current (LA-LBIC) technique which involves scanning a module with a laser beam and recording the current generated. Electroluminescence (EL) is emitted by a forward biased PV module and is used to identify defects in cell material. Defects such as cracks and broken fingers can be detected as well as material features such as grain boundaries. These techniques are used to in conjunction to characterise the modules used in this study. The modules investigated in this study each exhibit cell mismatch resulting from different causes. Each module is characterised using a combination of characterisation techniques which allows the effect of cell mismatch be investigated. EL imaging enabled cracks and defects, invisible to the naked eye, to be detected allowing the reduced performance observed in I-V curves to be explained. It was seen that the cracked cells have a significant effect on the current produced by a string, while the effect of delaminated areas is less severe. Hot spots are observed on weak cells indicating they are in reverse bias conditions and will degrade further with time. PSO parameter extraction from I-V curves revealed that the effect of module degradation of device parameters like series and shunt resistances. A module with cracked cells and degradation of the antireflective coating has low shunt resistance indicating current losses due to shunting. Similar shunting is observed in a module with delamination and moisture ingress. The extracted parameters are used to simulate the I-V curves of modules with reasonable fit. The fit could be improved around the “knee” of the I-V curve by improving the methods of parameter extraction. This study has shown the effects of cell mismatch on the performance and I-V curves of the PV modules. The different causes of cell mismatch are discussed and modules with different cell configuration and damage are characterised. The characterisation techniques used on each module provide information about the photoresponse, current generation, material properties and cell defects. A comprehensive understanding of these techniques allows the cell mismatch in the modules to be fully characterized.
- Full Text:
- Date Issued: 2012
- Authors: Crozier, Jacqueline Louise
- Date: 2012
- Subjects: Photovoltaic cells , Solar cells
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10545 , http://hdl.handle.net/10948/d1015059
- Description: Solar cells allow the energy from the sun to be converted into electrical energy; this makes solar energy much more environmentally friendly than fossil fuel energy sources. These solar cells are connected together in a photovoltaic (PV) module to provide the higher current, voltage and power outputs necessary for electrical applications. However, the performance of the PV module is limited by the performance of the individual cells. Cell mismatch occurs when some cells are damaged or shaded and produce lower current output than the other cells in the series connected string. The cell mismatch lowers the module performance and can result in further damage as the weak cells are reverse biased and dissipate heat. Bypass diodes can be connected into the module to increase the module current output and prevent further damage. Since cell mismatch results in a significant decrease in the performance of deployed modules it is important to fully understand and characterise its effect on PV modules. PV modules can be characterised using various techniques, each providing important information about the performance of the module. Most commonly the current-voltage (I-V) characteristic curve of a module is measured in outdoor, fully illuminated conditions. This allows performance parameters such as short circuit current (Isc), open circuit voltage (Voc) and maximum power (Pmax) to be determined. In addition to this the shape of the curve allows device parameters like series and shunt resistances to be determined using parameter extraction algorithms like Particle Swarm Optimisation (PSO). The extracted parameters can be entered into the diode equation to model the I-V curve of the module. The I-V characteristic of the module can also be used to identify poor current producing cells in the module by using the worst-case cell determination method. In this technique a cell is shaded and the greater the drop in current in the whole module the better the current production of the shaded cell. The photoresponse of cells in a module can be determined by the Large-area Light Beam Induced Current (LA-LBIC) technique which involves scanning a module with a laser beam and recording the current generated. Electroluminescence (EL) is emitted by a forward biased PV module and is used to identify defects in cell material. Defects such as cracks and broken fingers can be detected as well as material features such as grain boundaries. These techniques are used to in conjunction to characterise the modules used in this study. The modules investigated in this study each exhibit cell mismatch resulting from different causes. Each module is characterised using a combination of characterisation techniques which allows the effect of cell mismatch be investigated. EL imaging enabled cracks and defects, invisible to the naked eye, to be detected allowing the reduced performance observed in I-V curves to be explained. It was seen that the cracked cells have a significant effect on the current produced by a string, while the effect of delaminated areas is less severe. Hot spots are observed on weak cells indicating they are in reverse bias conditions and will degrade further with time. PSO parameter extraction from I-V curves revealed that the effect of module degradation of device parameters like series and shunt resistances. A module with cracked cells and degradation of the antireflective coating has low shunt resistance indicating current losses due to shunting. Similar shunting is observed in a module with delamination and moisture ingress. The extracted parameters are used to simulate the I-V curves of modules with reasonable fit. The fit could be improved around the “knee” of the I-V curve by improving the methods of parameter extraction. This study has shown the effects of cell mismatch on the performance and I-V curves of the PV modules. The different causes of cell mismatch are discussed and modules with different cell configuration and damage are characterised. The characterisation techniques used on each module provide information about the photoresponse, current generation, material properties and cell defects. A comprehensive understanding of these techniques allows the cell mismatch in the modules to be fully characterized.
- Full Text:
- Date Issued: 2012
To what extent can microfinance sustain the livelihoods of the women of Mdantsane (Ward N.U. 9)
- Authors: Cuntu, Somila
- Date: 2012
- Subjects: Microfinance -- South Africa -- Eastern Cape , Women in economic development --South Africa -- Eastern Cape , Women -- South Africa -- Eastern Cape -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9110 , http://hdl.handle.net/10948/d1014636
- Description: I have observed that in Mdantsane there is a clear gap between men and women, as people are tradition-bound, and men are often the breadwinners in their households, which leave some women sidelined and only left with household chores. Therefore this research aims to investigate these inequalities, and if microfinance can contribute positively towards the development of these women, so that they can develop and sustain their lifestyles. Chapter two of this research, containing available literature on this particular study which is sustainable livelihoods and microfinance for poor women, and covers both local as well as international studies. Here microfinance and sustainable livelihoods will be conceptualised accordingly so as to shed light on the subject. The third chapter covers the methodology used in the current study which clearly outlines the methodological framework, the research instruments, participants as well as the research design and procedure. The fourth chapter provides the findings and of the the current study, this will outline the main themes that surface and are prevalent among the participants. Chapter five will consist of the discussion of the results. Lastly chapter six will provide the conclusion as well as well as recommendations relevant to the results of this study.
- Full Text:
- Date Issued: 2012
- Authors: Cuntu, Somila
- Date: 2012
- Subjects: Microfinance -- South Africa -- Eastern Cape , Women in economic development --South Africa -- Eastern Cape , Women -- South Africa -- Eastern Cape -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9110 , http://hdl.handle.net/10948/d1014636
- Description: I have observed that in Mdantsane there is a clear gap between men and women, as people are tradition-bound, and men are often the breadwinners in their households, which leave some women sidelined and only left with household chores. Therefore this research aims to investigate these inequalities, and if microfinance can contribute positively towards the development of these women, so that they can develop and sustain their lifestyles. Chapter two of this research, containing available literature on this particular study which is sustainable livelihoods and microfinance for poor women, and covers both local as well as international studies. Here microfinance and sustainable livelihoods will be conceptualised accordingly so as to shed light on the subject. The third chapter covers the methodology used in the current study which clearly outlines the methodological framework, the research instruments, participants as well as the research design and procedure. The fourth chapter provides the findings and of the the current study, this will outline the main themes that surface and are prevalent among the participants. Chapter five will consist of the discussion of the results. Lastly chapter six will provide the conclusion as well as well as recommendations relevant to the results of this study.
- Full Text:
- Date Issued: 2012
Research and development of a preliminary South African voluntary carbon standard for landscape restoration projects
- Authors: Curran, Patrick
- Date: 2012
- Subjects: Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4748 , http://hdl.handle.net/10962/d1006968 , Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Description: The mandatory and voluntary carbon markets have both developed around the increasing trade of carbon offsets. In order to add legitimacy to an otherwise intangible commodity there has been a rise in the development of third party carbon certification standards, particularly in the voluntary market. These standards aim to provide independent, third party certification to projects that are developed specifically to generate and sell carbon offsets. South Africa has the opportunity to engage with these markets, but current participation in and certification of projects is sluggish. These projects have not taken off mainly due to the high transaction costs and lag times surrounding the current certification of projects', complex baseline methodologies, accounting uncertainty and the often bureaucratic systems surrounding the current voluntary carbon certification standards and methodologies. In order to overcome these pitfalls this project aimed to address these challenges through initiating the development of a preliminary South African voluntary carbon standard. This was done by: a) undertaking a critical assessment of the development of current carbon markets, with a particular focus on voluntary markets and third party certification, b) critically analysing the current voluntary carbon certification standards for best practices, pitfalls and weaknesses. To provide a better understanding of the historical development of voluntary certification standards, various established certification standards were evaluated, including the Forestry Stewardship Council (FSC), Marine Stewardship Council (MSC) and ISO 14000 standards. This analysis focussed on the challenges they faced in acceptance and in particular how they have managed to operationalize sustainable development within the certification process. In order to explicitly ensure the incorporation of a sustainable development assessment of projects under the proposed standard, an expert workshop was held with 14 experts from a wide variety of disciplines. These experts identified the crucial sustainable development challenges facing South Africa. They identified 12 sub-themes and 44 indicators that could be used to measure and incorporate sustainable development indicators into the certification process. These were then further developed through using the 'Input – Output – Outcome – Impact' framework model which allowed the indicators to be organised and understood and thus practical. The analysis of the voluntary certification standards and the development of the sustainable development indicator framework were ultimately incorporated into the development of the proposed South African voluntary carbon standard. The key approach to this standard is the incorporation and focus of the proposed standard to ensuring the generation of net SD benefits and placing them at the same level as carbon within the project design and development, validation and verification process. The full and effective integration of these has been missing within current fully fledged voluntary carbon standards, as they often rely on a mixture of project design standards to achieve this. Offering the inclusion of all components into one standard, specifically designed for South Africa, will not only assure SD credentials but also increase transparency and understanding, and reduce costs. This thesis allowed for the development of innovative new ideas and process focussed specifically at including and mainstreaming South Africa’s developmental challenges into the certification process. This is the hoped that the standard will effectively certify South African based landscape restoration projects, but also decrease costs and increase efficiencies in order to encourage the development of these projects. This preliminary standard not only aims to incorporate and address all the issues identified but also has the end goal of acting as the basis for future debate and development surrounding a potential South African voluntary carbon certification standard.
- Full Text:
- Date Issued: 2012
- Authors: Curran, Patrick
- Date: 2012
- Subjects: Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4748 , http://hdl.handle.net/10962/d1006968 , Carbon -- Environmental aspects -- Research -- South Africa , Carbon -- Standards -- Research , Restoration ecology -- Research -- South Africa , Environmental sciences -- Research
- Description: The mandatory and voluntary carbon markets have both developed around the increasing trade of carbon offsets. In order to add legitimacy to an otherwise intangible commodity there has been a rise in the development of third party carbon certification standards, particularly in the voluntary market. These standards aim to provide independent, third party certification to projects that are developed specifically to generate and sell carbon offsets. South Africa has the opportunity to engage with these markets, but current participation in and certification of projects is sluggish. These projects have not taken off mainly due to the high transaction costs and lag times surrounding the current certification of projects', complex baseline methodologies, accounting uncertainty and the often bureaucratic systems surrounding the current voluntary carbon certification standards and methodologies. In order to overcome these pitfalls this project aimed to address these challenges through initiating the development of a preliminary South African voluntary carbon standard. This was done by: a) undertaking a critical assessment of the development of current carbon markets, with a particular focus on voluntary markets and third party certification, b) critically analysing the current voluntary carbon certification standards for best practices, pitfalls and weaknesses. To provide a better understanding of the historical development of voluntary certification standards, various established certification standards were evaluated, including the Forestry Stewardship Council (FSC), Marine Stewardship Council (MSC) and ISO 14000 standards. This analysis focussed on the challenges they faced in acceptance and in particular how they have managed to operationalize sustainable development within the certification process. In order to explicitly ensure the incorporation of a sustainable development assessment of projects under the proposed standard, an expert workshop was held with 14 experts from a wide variety of disciplines. These experts identified the crucial sustainable development challenges facing South Africa. They identified 12 sub-themes and 44 indicators that could be used to measure and incorporate sustainable development indicators into the certification process. These were then further developed through using the 'Input – Output – Outcome – Impact' framework model which allowed the indicators to be organised and understood and thus practical. The analysis of the voluntary certification standards and the development of the sustainable development indicator framework were ultimately incorporated into the development of the proposed South African voluntary carbon standard. The key approach to this standard is the incorporation and focus of the proposed standard to ensuring the generation of net SD benefits and placing them at the same level as carbon within the project design and development, validation and verification process. The full and effective integration of these has been missing within current fully fledged voluntary carbon standards, as they often rely on a mixture of project design standards to achieve this. Offering the inclusion of all components into one standard, specifically designed for South Africa, will not only assure SD credentials but also increase transparency and understanding, and reduce costs. This thesis allowed for the development of innovative new ideas and process focussed specifically at including and mainstreaming South Africa’s developmental challenges into the certification process. This is the hoped that the standard will effectively certify South African based landscape restoration projects, but also decrease costs and increase efficiencies in order to encourage the development of these projects. This preliminary standard not only aims to incorporate and address all the issues identified but also has the end goal of acting as the basis for future debate and development surrounding a potential South African voluntary carbon certification standard.
- Full Text:
- Date Issued: 2012
Normative indicators for an isiXhosa-speaking population with disadvantaged education for tests of hand motor function and verbal fluency
- Authors: Da Silva Pita, Anita
- Date: 2012
- Subjects: Neuropsychological tests Hand -- Movements People with social disabilities -- Language People with social disabilities -- Education
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2959 , http://hdl.handle.net/10962/d1002468
- Description: The aim of the study was to obtain preliminary normative data for two tests of hand motor function (Successive Finger Tapping and Purdue Pegboard tests) and two tests of verbal fluency ("S"-Words-In-One-Minute and Words-In-One-Minute), administered in English, on a non-clinical sample of black, isiXhosa-speaking unskilled workers with a background of relatively disadvantaged former DET education (N = 33). The sample was equally distributed for gender; educational level was restricted to 11 - 12 years; age range was 18 - 40 years divided further into two age categories (18 - 29 and 30 - 40 years). Results of t-test comparative analyses revealed significant age effects on both trials of the Successive Finger Tapping test in the direction of the younger age group outperforming the older age group, and a marginal but consistent tendency towards poorer performance at an earlier age stage than proposed by the available literature, for the Purdue Pegboard, "S"Words- In-One-Minute and Words-In-One-Minute. Gender effects were only in evidence on the Purdue Pegboard in the direction of females outperforming males. A descriptive comparison of the norms acquired for the present study with available normative data for English first language speaking populations with higher levels and/ or relatively advantaged quality of education revealed consistently poorer performance for the present study. The findings highlight the effect of relatively low levels and/ or poor quality of education on both verbal and non-verbal neuropsychological test performance and confirm the need for demographically specific normative data.
- Full Text:
- Date Issued: 2012
- Authors: Da Silva Pita, Anita
- Date: 2012
- Subjects: Neuropsychological tests Hand -- Movements People with social disabilities -- Language People with social disabilities -- Education
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2959 , http://hdl.handle.net/10962/d1002468
- Description: The aim of the study was to obtain preliminary normative data for two tests of hand motor function (Successive Finger Tapping and Purdue Pegboard tests) and two tests of verbal fluency ("S"-Words-In-One-Minute and Words-In-One-Minute), administered in English, on a non-clinical sample of black, isiXhosa-speaking unskilled workers with a background of relatively disadvantaged former DET education (N = 33). The sample was equally distributed for gender; educational level was restricted to 11 - 12 years; age range was 18 - 40 years divided further into two age categories (18 - 29 and 30 - 40 years). Results of t-test comparative analyses revealed significant age effects on both trials of the Successive Finger Tapping test in the direction of the younger age group outperforming the older age group, and a marginal but consistent tendency towards poorer performance at an earlier age stage than proposed by the available literature, for the Purdue Pegboard, "S"Words- In-One-Minute and Words-In-One-Minute. Gender effects were only in evidence on the Purdue Pegboard in the direction of females outperforming males. A descriptive comparison of the norms acquired for the present study with available normative data for English first language speaking populations with higher levels and/ or relatively advantaged quality of education revealed consistently poorer performance for the present study. The findings highlight the effect of relatively low levels and/ or poor quality of education on both verbal and non-verbal neuropsychological test performance and confirm the need for demographically specific normative data.
- Full Text:
- Date Issued: 2012
The development of an orodispersible sildenafil citrate tablet intended for paediatric use
- Authors: Dagnolo, Bianca
- Date: 2012
- Subjects: Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3751 , http://hdl.handle.net/10962/d1003229 , Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Description: Sildenafil citrate (SC) is a phosphodiesterase-5 inhibitor that is used to treat pulmonary hypertension (PH) in paediatric patients. The purpose of these studies was to develop a formulation and manufacture an orodispersible tablet (ODT) that can be easily administered to neonates and children with PH. The advantages of ODT dosage forms include ease of administration, rapid dissolution of the API, SC. Furthermore the dosage form can be taken without water which is beneficial to patients without immediate access to potable fluids. A simple, rapid, accurate, precise and selective reversed-phase HPLC method was developed and validated in accordance with International Conference on Harmonization (ICH) guidelines and was successfully used for the analysis of SC as raw material and in SC containing pharmaceutical dosage forms. Preformulation studies were performed on SC, alone and in combination with potential excipients that could be used to make tablets. Investigations into potential interactions between SC and the excipients were performed using Differential Scanning Calorimetry (DSC) and Infrared Spectroscopy (IR). DSC results revealed that SC was compatible with all potential excipients except mannitol and magnesium stearate. However these interactions were not observed with IR and therefore it was concluded that the interactions were induced by the high temperatures that DSC operates at. Particle size and shape was also established by use of Scanning Electron Microscopy (SEM) and flow properties were monitored by calculating Carr’s Index (CI) and the Hausner Ratio (HR). Direct compression was used as the method of manufacture for SC tablets as this approach is simple and the most economic production approach. The powder blends were assessed for bulk and tapped density and the CI and HR were used to determine the flowability of the blends. The quality attributes of the resultant tablets that were monitored included uniformity of weight, friability, crushing strength, tensile strength, disintegration, wetting and in vitro dispersion times. Design of Experiments is an efficient statistical approach that has become a popular tool used in the pharmaceutical industry to optimize formulation compositions, as it allows for the investigation of several input factors at the same time whilst not using the tedious and traditional “ modification of one variable at a time” approach. A Central composite experimental design was chosen as the most appropriate means to optimize the formulation as it produces more accurate results as opposed to other experimental designs approaches as input factors are investigated at five different levels. Through the use of mathematical modelling, optimum concentrations of disintegrant(s) and an appropriate blending time were established. Analysis of the data from the experimental design and mathematical modelling studies reveal that no changes in disintegrant concentration or blending time altered the disintegration time of the formulation to any significant extent. This result is most likely due to the fact that the critical disintegrant concentration has been reached and increasing the disintegrant concentration further has no effect on disintegration time. It was also established that a change in the concentration of CMS and CRP altered the wetting time of the tablet significantly. Finally it was noted that there was a linear relationship between blending time and the uniformity of content of the tablets produced in these studies. The optimized product was a white tablet with a diameter of 7.31 mm with a thickness of 2.80mm.The dosage form had no visible cracks or evidence of picking or sticking. The tablet exhibits suitable friability and tensile strength while exhibiting a disintegration time of only 8s. Therefore an orodispersible tablet containing SC intended for paediatric use has been successfully developed, manufactured and optimized through the use of preformulation studies, appropriate quality control monitoring and mathematical modelling. These formulations require further optimization in respect of addition of flavours and or additional sweetening agents.
- Full Text:
- Date Issued: 2012
- Authors: Dagnolo, Bianca
- Date: 2012
- Subjects: Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3751 , http://hdl.handle.net/10962/d1003229 , Drug development -- Children -- Research -- South Africa , Pulmonary hypertension -- Children -- Research , Tablets (Medicine) -- Development , Pharmaceutical chemistry -- Research
- Description: Sildenafil citrate (SC) is a phosphodiesterase-5 inhibitor that is used to treat pulmonary hypertension (PH) in paediatric patients. The purpose of these studies was to develop a formulation and manufacture an orodispersible tablet (ODT) that can be easily administered to neonates and children with PH. The advantages of ODT dosage forms include ease of administration, rapid dissolution of the API, SC. Furthermore the dosage form can be taken without water which is beneficial to patients without immediate access to potable fluids. A simple, rapid, accurate, precise and selective reversed-phase HPLC method was developed and validated in accordance with International Conference on Harmonization (ICH) guidelines and was successfully used for the analysis of SC as raw material and in SC containing pharmaceutical dosage forms. Preformulation studies were performed on SC, alone and in combination with potential excipients that could be used to make tablets. Investigations into potential interactions between SC and the excipients were performed using Differential Scanning Calorimetry (DSC) and Infrared Spectroscopy (IR). DSC results revealed that SC was compatible with all potential excipients except mannitol and magnesium stearate. However these interactions were not observed with IR and therefore it was concluded that the interactions were induced by the high temperatures that DSC operates at. Particle size and shape was also established by use of Scanning Electron Microscopy (SEM) and flow properties were monitored by calculating Carr’s Index (CI) and the Hausner Ratio (HR). Direct compression was used as the method of manufacture for SC tablets as this approach is simple and the most economic production approach. The powder blends were assessed for bulk and tapped density and the CI and HR were used to determine the flowability of the blends. The quality attributes of the resultant tablets that were monitored included uniformity of weight, friability, crushing strength, tensile strength, disintegration, wetting and in vitro dispersion times. Design of Experiments is an efficient statistical approach that has become a popular tool used in the pharmaceutical industry to optimize formulation compositions, as it allows for the investigation of several input factors at the same time whilst not using the tedious and traditional “ modification of one variable at a time” approach. A Central composite experimental design was chosen as the most appropriate means to optimize the formulation as it produces more accurate results as opposed to other experimental designs approaches as input factors are investigated at five different levels. Through the use of mathematical modelling, optimum concentrations of disintegrant(s) and an appropriate blending time were established. Analysis of the data from the experimental design and mathematical modelling studies reveal that no changes in disintegrant concentration or blending time altered the disintegration time of the formulation to any significant extent. This result is most likely due to the fact that the critical disintegrant concentration has been reached and increasing the disintegrant concentration further has no effect on disintegration time. It was also established that a change in the concentration of CMS and CRP altered the wetting time of the tablet significantly. Finally it was noted that there was a linear relationship between blending time and the uniformity of content of the tablets produced in these studies. The optimized product was a white tablet with a diameter of 7.31 mm with a thickness of 2.80mm.The dosage form had no visible cracks or evidence of picking or sticking. The tablet exhibits suitable friability and tensile strength while exhibiting a disintegration time of only 8s. Therefore an orodispersible tablet containing SC intended for paediatric use has been successfully developed, manufactured and optimized through the use of preformulation studies, appropriate quality control monitoring and mathematical modelling. These formulations require further optimization in respect of addition of flavours and or additional sweetening agents.
- Full Text:
- Date Issued: 2012
Refuse collection management practices in the Buffalo City Municipality
- Authors: Damane, Mcebisi
- Date: 2012
- Subjects: Refuse collection -- South Africa -- Eastern Cape -- Management , Refuse and refuse disposal -- South Africa -- Eastern Cape -- Management , Refuse collection vehicles -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8266 , http://hdl.handle.net/10948/d1013703
- Description: The ineffective and inefficient management and collection of municipal solid waste is a significant problem in cities of many developing countries. South Africa as a developing country is also faced with the same problem. Buffalo City Municipality with its fast growing urban population is not immune from the problem. Due to continuing population growth, urbanisation, industrialisation and higher consumption levels which started after the demise of the previous legislations which stifled the advancement of black communities, the generation and management of municipal solid waste in developing countries is likely to worsen. The uncollected waste and rampant littering generates pollution and poses risks to human health and the environment. Regulations guiding the treatment and the disposal of waste are not followed to the letter by authorities. There are no measures in place to ensure that the environment is sustained, and even if there are they are not fully implemented. This affects municipalities negatively in various aspects. Tourism that is known to boost ailing and weak local economies is affected. Properties are devaluated and potential developers turn their backs on municipalities that are not well managed. It is the low-income communities that suffer the brunt of the inefficiency and poor service delivery. This status quo is not acceptable eighteen years after the attainment of democracy and the adoption of the Constitution in South Africa. This study analyses the challenges and factors that cause Buffalo City Municipality (BCM) not to deliver services efficiently and successfully in respect of waste management. It also attempts to check alternatives and solutions as gathered from other cities in a similar predicament. Municipalities are encouraged to adopt Local Economic Development (LED) principles and establish public- public partnerships and private- public partnerships thereby utilizing communities in refuse collection and waste management.
- Full Text:
- Date Issued: 2012
- Authors: Damane, Mcebisi
- Date: 2012
- Subjects: Refuse collection -- South Africa -- Eastern Cape -- Management , Refuse and refuse disposal -- South Africa -- Eastern Cape -- Management , Refuse collection vehicles -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8266 , http://hdl.handle.net/10948/d1013703
- Description: The ineffective and inefficient management and collection of municipal solid waste is a significant problem in cities of many developing countries. South Africa as a developing country is also faced with the same problem. Buffalo City Municipality with its fast growing urban population is not immune from the problem. Due to continuing population growth, urbanisation, industrialisation and higher consumption levels which started after the demise of the previous legislations which stifled the advancement of black communities, the generation and management of municipal solid waste in developing countries is likely to worsen. The uncollected waste and rampant littering generates pollution and poses risks to human health and the environment. Regulations guiding the treatment and the disposal of waste are not followed to the letter by authorities. There are no measures in place to ensure that the environment is sustained, and even if there are they are not fully implemented. This affects municipalities negatively in various aspects. Tourism that is known to boost ailing and weak local economies is affected. Properties are devaluated and potential developers turn their backs on municipalities that are not well managed. It is the low-income communities that suffer the brunt of the inefficiency and poor service delivery. This status quo is not acceptable eighteen years after the attainment of democracy and the adoption of the Constitution in South Africa. This study analyses the challenges and factors that cause Buffalo City Municipality (BCM) not to deliver services efficiently and successfully in respect of waste management. It also attempts to check alternatives and solutions as gathered from other cities in a similar predicament. Municipalities are encouraged to adopt Local Economic Development (LED) principles and establish public- public partnerships and private- public partnerships thereby utilizing communities in refuse collection and waste management.
- Full Text:
- Date Issued: 2012
The implications of rural-urban migration on employment and household income with particular reference to Lesotho
- Authors: Damane, Moeti
- Date: 2012
- Subjects: Rural-urban migration -- Employment -- Lesotho Informal sector (Economics) -- Lesotho Lesotho -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1002 , http://hdl.handle.net/10962/d1002737
- Description: The research investigates the impact of internal rural - urban migration III Lesotho on household income and employment. Using data gathered from the 2002/03 household survey, the 2006 nationwide census and a questionnaire on rural - urban migration in Lesotho administered to 500 respondents in Maseru and Leribe, we estimate a logit model of the probability of employment in Lesotho in 2008 given a set of independent variables. The independent variables are respondent's work experience; years of education completed; employment status in 2004; employment status in 2008; gender; job skill level; place of residence in 2004 and a categorical variable that measures whether or not the respondent is a rural - urban migrant. The results suggest that migration and work experience have no significant impact on an individual's likelihood of being employed in the country's formal sector. Also, it was found that the higher the level of education an individual has, the less likely are their chances of employment in the country's formal sector because of the lack of formal jobs in the urban areas. Over 50% of Lesotho's workforce employed in the urban areas was discovered to work in the informal sector. The study concludes that there is a lack of jobs in Lesotho's urban formal sector that results in a thriving informal sector. The advantages of informal sector jobs to the rural - urban migrant include an increase in their standard of living as well as that of their family members left behind in the rural areas but the disadvantages include low levels of investor confidence that lead to a decrease in overall economic development and growth in the country.
- Full Text:
- Date Issued: 2012
- Authors: Damane, Moeti
- Date: 2012
- Subjects: Rural-urban migration -- Employment -- Lesotho Informal sector (Economics) -- Lesotho Lesotho -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1002 , http://hdl.handle.net/10962/d1002737
- Description: The research investigates the impact of internal rural - urban migration III Lesotho on household income and employment. Using data gathered from the 2002/03 household survey, the 2006 nationwide census and a questionnaire on rural - urban migration in Lesotho administered to 500 respondents in Maseru and Leribe, we estimate a logit model of the probability of employment in Lesotho in 2008 given a set of independent variables. The independent variables are respondent's work experience; years of education completed; employment status in 2004; employment status in 2008; gender; job skill level; place of residence in 2004 and a categorical variable that measures whether or not the respondent is a rural - urban migrant. The results suggest that migration and work experience have no significant impact on an individual's likelihood of being employed in the country's formal sector. Also, it was found that the higher the level of education an individual has, the less likely are their chances of employment in the country's formal sector because of the lack of formal jobs in the urban areas. Over 50% of Lesotho's workforce employed in the urban areas was discovered to work in the informal sector. The study concludes that there is a lack of jobs in Lesotho's urban formal sector that results in a thriving informal sector. The advantages of informal sector jobs to the rural - urban migrant include an increase in their standard of living as well as that of their family members left behind in the rural areas but the disadvantages include low levels of investor confidence that lead to a decrease in overall economic development and growth in the country.
- Full Text:
- Date Issued: 2012
Best practices to create an enabling environment for SME incubation in South Africa
- Authors: Dames, Ricardo Shane
- Date: 2012
- Subjects: Business incubators -- South Africa , New business enterprises -- South Africa , Small businesses -- South Africa -- Management
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:9301 , http://hdl.handle.net/10948/d1015031
- Description: The humble beginnings of business incubators date back to the 1970s in the USA and United Kingdom, where abandoned industrial buildings were converted to rent out to small businesses. South Africa (SA) was first introduced to business incubation in the 1980s when the Small Business Development Corporation (SBDC) established a number of business ‘hives’ and provided business space to entrepreneurs to operate their businesses. In their most basic form, business incubators provide a safe and nurturing environment for entrepreneurs to establish their small businesses. While in incubation, the Small and Medium Enterprises (SMEs) are supported with a number of services which assist their growth and development until they are able to exit the incubator as sustainable and viable businesses. Global incubator models have matured significantly, and now include assisting with business idea generation, accelerating business start-ups and commercialisation processes, and identifying high-growth orientated SMEs to assist them with gaining market access. The establishment of business incubators was a government-driven initiative, and more than 33 SME incubators exist in SA. Most of the incubators are government-funded, and have focused on the establishment and growth of SMEs to act as a catalyst to promote economic development and alleviate socio-economic challenges such as unemployment and poverty. Despite these noble objectives, incubation in SA has not been fully utilised, and a high SME failure rate still prevails in the country. One of the reasons for SME failure may be ascribed to the lack of an enabling SME incubation environment in SA. When compared to other developing countries such as Brazil with as many as 400 incubators, it is clear that the SA incubation industry still needs further development. The purpose of this study therefore was to ascertain the best practices of global business incubators in both developed and developing countries, and how SA incubators could learn from these best practices to create a more conducive and enabling SME incubation environment. Background literature on business incubation with a specific focus on best practices in world incubators in both developed and developing countries, was reviewed. Some of the literature reviewed included Aernoudt (2004), Buys and Mbewana (2007) and Chandra (2009). From the literature review, four main best practice areas were identified, namely strategic focus, sources of funding, incubator services, and the role of government. The study followed a qualitative approach, and an interview schedule was developed to seek the perceptions of incubator managers on how the four identified best practices can be utilised to create an enabling SA incubation environment. A survey was conducted by interviewing 14 incubator managers (twelve government and two private) in SA. Data was collected over a six-month period, using face-to-face and telephonic interviews. Data was analysed using the content analysis, constant comparison, grounded theory and case study methods. The biographical profiles of the incubator managers and incubators were presented in case studies. An initial analysis was made to identify themes and sub themes within the four best practices explored, using the constant comparison method. Thereafter a provincial comparative analysis was made, as well as a comparison of government funded versus privately funded incubators. The findings suggested that there is a relatively high turnover in incubator management, and that they often do not have incubator management experience. A provincial comparison of SA incubators revealed that their strategic focuses are greatly influenced by the industry prevailing in the various provinces. All SA incubators provide pre- and post incubation services, but few are utilising virtual incubation. Most SA incubators are government-funded, and some use a hybrid funding model. It was evident that most SA incubators are aware of government policies and programmes available to assist them on local, provincial and national levels. A comparison of the best practices of two developing countries and three developed countries, as well as suggestions made by SA incubator managers indicated that SA has indeed followed best practices from both developing and developed countries, but there are areas of non-alignment which provide scope for improvement, to create a more conducive and enabling incubation environment. This study recommends that incubators should have an entrepreneurial focus, and reposition and align their strategic focus with government policies and instruments. SA incubators must pursue opportunities for virtual incubation as well as linkages with academic institutions, in order to offer value-added services such as research, development and commercialisation of the product ideas. Incubators in SA must pursue a hybrid funding model with a combination of government and private funding, and generate some or their own income. With regard to the role of government, it is recommended that the roll-out of more industry-specific incubators be privatised, and that an overseeing body for incubation be established.
- Full Text:
- Date Issued: 2012
- Authors: Dames, Ricardo Shane
- Date: 2012
- Subjects: Business incubators -- South Africa , New business enterprises -- South Africa , Small businesses -- South Africa -- Management
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:9301 , http://hdl.handle.net/10948/d1015031
- Description: The humble beginnings of business incubators date back to the 1970s in the USA and United Kingdom, where abandoned industrial buildings were converted to rent out to small businesses. South Africa (SA) was first introduced to business incubation in the 1980s when the Small Business Development Corporation (SBDC) established a number of business ‘hives’ and provided business space to entrepreneurs to operate their businesses. In their most basic form, business incubators provide a safe and nurturing environment for entrepreneurs to establish their small businesses. While in incubation, the Small and Medium Enterprises (SMEs) are supported with a number of services which assist their growth and development until they are able to exit the incubator as sustainable and viable businesses. Global incubator models have matured significantly, and now include assisting with business idea generation, accelerating business start-ups and commercialisation processes, and identifying high-growth orientated SMEs to assist them with gaining market access. The establishment of business incubators was a government-driven initiative, and more than 33 SME incubators exist in SA. Most of the incubators are government-funded, and have focused on the establishment and growth of SMEs to act as a catalyst to promote economic development and alleviate socio-economic challenges such as unemployment and poverty. Despite these noble objectives, incubation in SA has not been fully utilised, and a high SME failure rate still prevails in the country. One of the reasons for SME failure may be ascribed to the lack of an enabling SME incubation environment in SA. When compared to other developing countries such as Brazil with as many as 400 incubators, it is clear that the SA incubation industry still needs further development. The purpose of this study therefore was to ascertain the best practices of global business incubators in both developed and developing countries, and how SA incubators could learn from these best practices to create a more conducive and enabling SME incubation environment. Background literature on business incubation with a specific focus on best practices in world incubators in both developed and developing countries, was reviewed. Some of the literature reviewed included Aernoudt (2004), Buys and Mbewana (2007) and Chandra (2009). From the literature review, four main best practice areas were identified, namely strategic focus, sources of funding, incubator services, and the role of government. The study followed a qualitative approach, and an interview schedule was developed to seek the perceptions of incubator managers on how the four identified best practices can be utilised to create an enabling SA incubation environment. A survey was conducted by interviewing 14 incubator managers (twelve government and two private) in SA. Data was collected over a six-month period, using face-to-face and telephonic interviews. Data was analysed using the content analysis, constant comparison, grounded theory and case study methods. The biographical profiles of the incubator managers and incubators were presented in case studies. An initial analysis was made to identify themes and sub themes within the four best practices explored, using the constant comparison method. Thereafter a provincial comparative analysis was made, as well as a comparison of government funded versus privately funded incubators. The findings suggested that there is a relatively high turnover in incubator management, and that they often do not have incubator management experience. A provincial comparison of SA incubators revealed that their strategic focuses are greatly influenced by the industry prevailing in the various provinces. All SA incubators provide pre- and post incubation services, but few are utilising virtual incubation. Most SA incubators are government-funded, and some use a hybrid funding model. It was evident that most SA incubators are aware of government policies and programmes available to assist them on local, provincial and national levels. A comparison of the best practices of two developing countries and three developed countries, as well as suggestions made by SA incubator managers indicated that SA has indeed followed best practices from both developing and developed countries, but there are areas of non-alignment which provide scope for improvement, to create a more conducive and enabling incubation environment. This study recommends that incubators should have an entrepreneurial focus, and reposition and align their strategic focus with government policies and instruments. SA incubators must pursue opportunities for virtual incubation as well as linkages with academic institutions, in order to offer value-added services such as research, development and commercialisation of the product ideas. Incubators in SA must pursue a hybrid funding model with a combination of government and private funding, and generate some or their own income. With regard to the role of government, it is recommended that the roll-out of more industry-specific incubators be privatised, and that an overseeing body for incubation be established.
- Full Text:
- Date Issued: 2012
Navigating the pathways to opening a new, effective community school : a case study in the Nelson Mandela Metropolitan Municipality of South Africa
- Authors: Damons, Bruce Peter
- Date: 2012
- Subjects: Community schools -- South Africa -- Port Elizabeth , Educational leadership -- South Africa -- Port Elizabeth , Teachers -- Recruiting -- South Africa -- Port Elizabeth , Teachers -- Training of -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9578 , http://hdl.handle.net/10948/d1019857
- Description: The provision of low cost housing has become one of the current South African government‟s top priorities. With the establishment of these new housing developments comes the need for accompanying social infrastructure. This includes the provisioning of schools, police stations, clinics and sports fields. In this study, I attempted to identify and explore the key basic elements that needed to be present when opening a new community school in one of these low income housing developments. The study gives voice to what key stakeholders thought these elements should be. The stakeholders were the teachers and community volunteers, which included parents of the learners. They actively participated in this study through the methodology of participatory action learning and action research (PALAR). The participants identified strong, compassionate and visionary leadership as an essential element that need to be present when opening up a new school. The study further shows that this leadership must have some knowledge of effective management systems in order to support the establishment of a new school. The findings also show that leadership and the effective implementation of these management systems rely heavily on the support of a variety of internal and external stakeholders, especially when support was lacking from the Department of Basic Education. The study further shows that the roles of the various stakeholders should be clearly defined and managed, so as to avoid tensions that might arise by having a large number of people involved in a confined space like a school. Teachers and community volunteers emerged as the key stakeholders who contributed to the effective functioning of the new school. Their continued involvement in the school requires on-going professional development and support.
- Full Text:
- Date Issued: 2012
- Authors: Damons, Bruce Peter
- Date: 2012
- Subjects: Community schools -- South Africa -- Port Elizabeth , Educational leadership -- South Africa -- Port Elizabeth , Teachers -- Recruiting -- South Africa -- Port Elizabeth , Teachers -- Training of -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9578 , http://hdl.handle.net/10948/d1019857
- Description: The provision of low cost housing has become one of the current South African government‟s top priorities. With the establishment of these new housing developments comes the need for accompanying social infrastructure. This includes the provisioning of schools, police stations, clinics and sports fields. In this study, I attempted to identify and explore the key basic elements that needed to be present when opening a new community school in one of these low income housing developments. The study gives voice to what key stakeholders thought these elements should be. The stakeholders were the teachers and community volunteers, which included parents of the learners. They actively participated in this study through the methodology of participatory action learning and action research (PALAR). The participants identified strong, compassionate and visionary leadership as an essential element that need to be present when opening up a new school. The study further shows that this leadership must have some knowledge of effective management systems in order to support the establishment of a new school. The findings also show that leadership and the effective implementation of these management systems rely heavily on the support of a variety of internal and external stakeholders, especially when support was lacking from the Department of Basic Education. The study further shows that the roles of the various stakeholders should be clearly defined and managed, so as to avoid tensions that might arise by having a large number of people involved in a confined space like a school. Teachers and community volunteers emerged as the key stakeholders who contributed to the effective functioning of the new school. Their continued involvement in the school requires on-going professional development and support.
- Full Text:
- Date Issued: 2012
The meaning of place of 'effective management' in the context of South African domestic tax law
- Authors: Daniels, Paul
- Date: 2012
- Subjects: Double taxation -- Treaties , Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8960 , http://hdl.handle.net/10948/d1018822
- Description: South Africa has a residence based system of taxation in which South African tax residents are taxed on their worldwide income. A company or other artificial person is regarded as a South African resident for tax purposes if it is incorporated, established or formed in South Africa or if its ‗effective management‘ is located in South Africa. Where a tax treaty determines in terms of its tie breaker rule that an artificial person is not resident in South Africa for treaty purposes, the company will also not be regarded as a tax resident in terms of South African domestic law. Treaties to which South Africa is party will often use the effective management‘ as the tie-breaker where a person other than an individual is resident in both Contracting states in terms of the respective states‘ domestic laws. The tests of ‗incorporation, established and formed‘ provide simplicity and certainty to governments but are easily open to manipulation by taxpayers. Therefore, the legislature found it necessary to incorporate effective management‘ as a test for residency into the Act. Effective management‘ is a substance over form concept which be described as a function which embodies the periodic, most senior executive management functions, which are required for the management of the affairs of the entity as whole. The test of effective management‘ by its very nature is concerned with where the crucial decisions are made in order to make a business function. To identify the location of effective management‘ it is necessary to enquire who calls the shots‘ in the context of the management of the company as opposed to who controls the company notwithstanding that there may in certain instances be overlap between the two functions. It is submitted that any person who, on the face of it seems unconnected to a company, could effectively manage‘ a company if that person is, in substance, responsible for the most senior executive management functions of the company. The discussion paper issued by SARS recognises the principal difficulties experienced with its current interpretation of the concept and makes valuable points, concessions and recommendations. It also recognised that the 'calling of shots' by the most senior executive is a critical marker of effective management‘ and that control of a company is irrelevant in determining effective management‘. To determine who effectively manages‘ a company each situation would have to be analysed on its own as it is not possible to create a definitive rule on the concept. In many cases the nature of the entity and its modus operandi would have to be taken into account to determine effective management.
- Full Text:
- Date Issued: 2012
- Authors: Daniels, Paul
- Date: 2012
- Subjects: Double taxation -- Treaties , Management
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8960 , http://hdl.handle.net/10948/d1018822
- Description: South Africa has a residence based system of taxation in which South African tax residents are taxed on their worldwide income. A company or other artificial person is regarded as a South African resident for tax purposes if it is incorporated, established or formed in South Africa or if its ‗effective management‘ is located in South Africa. Where a tax treaty determines in terms of its tie breaker rule that an artificial person is not resident in South Africa for treaty purposes, the company will also not be regarded as a tax resident in terms of South African domestic law. Treaties to which South Africa is party will often use the effective management‘ as the tie-breaker where a person other than an individual is resident in both Contracting states in terms of the respective states‘ domestic laws. The tests of ‗incorporation, established and formed‘ provide simplicity and certainty to governments but are easily open to manipulation by taxpayers. Therefore, the legislature found it necessary to incorporate effective management‘ as a test for residency into the Act. Effective management‘ is a substance over form concept which be described as a function which embodies the periodic, most senior executive management functions, which are required for the management of the affairs of the entity as whole. The test of effective management‘ by its very nature is concerned with where the crucial decisions are made in order to make a business function. To identify the location of effective management‘ it is necessary to enquire who calls the shots‘ in the context of the management of the company as opposed to who controls the company notwithstanding that there may in certain instances be overlap between the two functions. It is submitted that any person who, on the face of it seems unconnected to a company, could effectively manage‘ a company if that person is, in substance, responsible for the most senior executive management functions of the company. The discussion paper issued by SARS recognises the principal difficulties experienced with its current interpretation of the concept and makes valuable points, concessions and recommendations. It also recognised that the 'calling of shots' by the most senior executive is a critical marker of effective management‘ and that control of a company is irrelevant in determining effective management‘. To determine who effectively manages‘ a company each situation would have to be analysed on its own as it is not possible to create a definitive rule on the concept. In many cases the nature of the entity and its modus operandi would have to be taken into account to determine effective management.
- Full Text:
- Date Issued: 2012
Pre-concentration of toxic metals using electrospun amino-functionalized nylon-6 nanofibre sorbent
- Darko, G, Sobola, A, Adewuyi, Sheriff, Okonkwo, J O, Torto, N
- Authors: Darko, G , Sobola, A , Adewuyi, Sheriff , Okonkwo, J O , Torto, N
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6571 , http://hdl.handle.net/10962/d1004134
- Description: This paper presents a new approach for pre-concentrating toxic metals (As, Cd, Ni and Pb) in aqueous environments using an amino-functionalized electrospun nanofibre sorbent. The sorbent, composed of nanofibres of average diameter 80 ± 10 nm and specific surface area of 58m2 g–1, exhibited fast adsorption kinetics (<20 min) for As, Cd, Ni and Pb. The optimalpHfor the uptake of As, Cd, Ni and Pb were 5.5, 6.0, 6.5 and 11, respectively. The adsorption process best fitted the Freundlich isothermand followed the first-order kinetics. The highest pre-concentration achieved using the sorbent was 41.99 (Ni in treated wastewater). The capacity of the sorbent to pre-concentrate the toxic metals was compared with those of aqua regia and HNO3+H2O2 digestions. The pre-concentration factors achieved for Cd in river water samples can be ranked as aqua regia digestion (0.73) > adsorption (0.34)>HNO3+H2O2 (0.23) digestion.Asimilar trend was observed for Ni in river water as well as Ni andCdin tap water samples. Pb ions in the river water samples were pre-concentrated slightly better using the two digestion methods pre-concentration factors ~22) compared to adsorption method (pre-concentration factor ~21). The use of the electrospun amino-functionalized nanofibre sorbent presentsanefficientand cost-effective alternative for pre-concentration of toxic metals inaqueousenvironments.
- Full Text:
- Date Issued: 2012
- Authors: Darko, G , Sobola, A , Adewuyi, Sheriff , Okonkwo, J O , Torto, N
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6571 , http://hdl.handle.net/10962/d1004134
- Description: This paper presents a new approach for pre-concentrating toxic metals (As, Cd, Ni and Pb) in aqueous environments using an amino-functionalized electrospun nanofibre sorbent. The sorbent, composed of nanofibres of average diameter 80 ± 10 nm and specific surface area of 58m2 g–1, exhibited fast adsorption kinetics (<20 min) for As, Cd, Ni and Pb. The optimalpHfor the uptake of As, Cd, Ni and Pb were 5.5, 6.0, 6.5 and 11, respectively. The adsorption process best fitted the Freundlich isothermand followed the first-order kinetics. The highest pre-concentration achieved using the sorbent was 41.99 (Ni in treated wastewater). The capacity of the sorbent to pre-concentrate the toxic metals was compared with those of aqua regia and HNO3+H2O2 digestions. The pre-concentration factors achieved for Cd in river water samples can be ranked as aqua regia digestion (0.73) > adsorption (0.34)>HNO3+H2O2 (0.23) digestion.Asimilar trend was observed for Ni in river water as well as Ni andCdin tap water samples. Pb ions in the river water samples were pre-concentrated slightly better using the two digestion methods pre-concentration factors ~22) compared to adsorption method (pre-concentration factor ~21). The use of the electrospun amino-functionalized nanofibre sorbent presentsanefficientand cost-effective alternative for pre-concentration of toxic metals inaqueousenvironments.
- Full Text:
- Date Issued: 2012
Pre-concentration of heavy metals in aqueous environments using electrospun polymer nanofiber sorbents
- Authors: Darko, Godfred
- Date: 2012
- Subjects: Heavy metals -- Absorption and adsorption -- Research Nanochemistry -- Research Polystyrene -- Research Polyamides -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4337 , http://hdl.handle.net/10962/d1004998
- Description: This thesis presents an alternative approach for pre-concentrating heavy metals in aqueous environments using electro spun polymer nanofiber sorbents. The conditions for electrospinning polyethersulfone, polystyrene, polysulfone and polyamide-6 were optimized. The morphologies and porosities of the electrospun nanofibers were studied using SEM and BET nitrogen gas adsorptions. The nanofibers had mesoporous morphologies with specific surface areas up to 58 m2/g. The electro spun nanofiber sorbents were characterized in terms of their tunability for both uptake and release of heavy metals. The usability of the sorbent was also assessed. The sorbents showed fast adsorption kinetics for heavy metals « 20 min for As, Cu, Ni and Pb) in different aqueous environments. The adsorption characteristics of the sorbents best fitted the Freundlich isotherm and followed the first order kinetics. The efficiencies of adsorption and desorption of heavy metals on both imidazolyl-functionalized polystyrene and amino-functionalized polysulfone sorbents were more than 95% up to the fifth cycle of usage. Reusability improved dramatically (up to 10 runs of usage) when mechanically stable amino-functionalized nylon-6 electro spun nanofibers were used. The capacity of the amino-functionalized nylon-6 sorbent to pre-concentrate heavy metals compared very favourably with those of aqua regia and HN03+H202 digestions especially in less complex matrices. Due to their highly porous nature, the electro spun nanofibers exhibited high adsorption capacities (up to 50 mg/g) for heavy metal ions. The loading capacities achieved with the imidazolyl-functionalized sorbent were higher than those for amino-functionalized mesoporous silica and biomass-based sorbents. The electro spun nanofiber sorbents presents an efficient and cost effective alternative for preconcentrating heavy metals in aqueous environments.
- Full Text:
- Date Issued: 2012
- Authors: Darko, Godfred
- Date: 2012
- Subjects: Heavy metals -- Absorption and adsorption -- Research Nanochemistry -- Research Polystyrene -- Research Polyamides -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4337 , http://hdl.handle.net/10962/d1004998
- Description: This thesis presents an alternative approach for pre-concentrating heavy metals in aqueous environments using electro spun polymer nanofiber sorbents. The conditions for electrospinning polyethersulfone, polystyrene, polysulfone and polyamide-6 were optimized. The morphologies and porosities of the electrospun nanofibers were studied using SEM and BET nitrogen gas adsorptions. The nanofibers had mesoporous morphologies with specific surface areas up to 58 m2/g. The electro spun nanofiber sorbents were characterized in terms of their tunability for both uptake and release of heavy metals. The usability of the sorbent was also assessed. The sorbents showed fast adsorption kinetics for heavy metals « 20 min for As, Cu, Ni and Pb) in different aqueous environments. The adsorption characteristics of the sorbents best fitted the Freundlich isotherm and followed the first order kinetics. The efficiencies of adsorption and desorption of heavy metals on both imidazolyl-functionalized polystyrene and amino-functionalized polysulfone sorbents were more than 95% up to the fifth cycle of usage. Reusability improved dramatically (up to 10 runs of usage) when mechanically stable amino-functionalized nylon-6 electro spun nanofibers were used. The capacity of the amino-functionalized nylon-6 sorbent to pre-concentrate heavy metals compared very favourably with those of aqua regia and HN03+H202 digestions especially in less complex matrices. Due to their highly porous nature, the electro spun nanofibers exhibited high adsorption capacities (up to 50 mg/g) for heavy metal ions. The loading capacities achieved with the imidazolyl-functionalized sorbent were higher than those for amino-functionalized mesoporous silica and biomass-based sorbents. The electro spun nanofiber sorbents presents an efficient and cost effective alternative for preconcentrating heavy metals in aqueous environments.
- Full Text:
- Date Issued: 2012
The direct use value of municipal commonage goods and services to urban households in the Eastern Cape, South Africa
- Davenport, Nicholas A, Shackleton, Charlie M, Gambiza, James
- Authors: Davenport, Nicholas A , Shackleton, Charlie M , Gambiza, James
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181071 , vital:43696 , xlink:href="https://doi.org/10.1016/j.landusepol.2011.09.008"
- Description: To redress past racial discrepancies in ownership and tenure, the ANC government of South Africa initiated programmes to make land accessible to the previously disadvantaged. A key component of the national land reform programme was the provision of commonage lands to urban municipalities for use by the urban poor. However, there has been no assessment of the contribution that urban commonage makes to previously disadvantaged households. This study assessed the economic benefits of the commonage programme to local households, through an in-depth survey of 90 households across three small towns in the Eastern Cape of South Africa. We examined the marketed and non-marketed consumptive direct-use values of land-based livelihoods on commonage, calculated via the ‘own reported values’ approach. The results indicate that a proportion of South Africa's urban population rely to some degree on municipal commonage for part of their livelihoods. Commonage contributions to total livelihood incomes ranged between 14 and 20%. If the contributions from commonage were excluded, the incomes of over 10% of households in each study town would drop below the poverty line. Overall, the value of harvests from commonage was worth over R1 000 (US$ 142) per hectare per year and over R4.7 million (US$ 0.68 million) per commonage per year. However, the extent and nature of use and reliance was not uniform among households, so that we developed a typology of commonage users, with four types being identified. However, rapidly growing urban populations and high levels of poverty potentially threaten the sustainability of commonage resource use. Yet the national land reform programme focuses largely on the transfer of land to municipalities and not on sustainable management. Municipalities, in turn, invest relatively little in commonage management, and the little they do is focussed on livestock production. Non-timber forest products are not considered at all, even though this study shows that they are a vital resource for the urban poor, notably for energy and construction materials.
- Full Text:
- Date Issued: 2012
- Authors: Davenport, Nicholas A , Shackleton, Charlie M , Gambiza, James
- Date: 2012
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181071 , vital:43696 , xlink:href="https://doi.org/10.1016/j.landusepol.2011.09.008"
- Description: To redress past racial discrepancies in ownership and tenure, the ANC government of South Africa initiated programmes to make land accessible to the previously disadvantaged. A key component of the national land reform programme was the provision of commonage lands to urban municipalities for use by the urban poor. However, there has been no assessment of the contribution that urban commonage makes to previously disadvantaged households. This study assessed the economic benefits of the commonage programme to local households, through an in-depth survey of 90 households across three small towns in the Eastern Cape of South Africa. We examined the marketed and non-marketed consumptive direct-use values of land-based livelihoods on commonage, calculated via the ‘own reported values’ approach. The results indicate that a proportion of South Africa's urban population rely to some degree on municipal commonage for part of their livelihoods. Commonage contributions to total livelihood incomes ranged between 14 and 20%. If the contributions from commonage were excluded, the incomes of over 10% of households in each study town would drop below the poverty line. Overall, the value of harvests from commonage was worth over R1 000 (US$ 142) per hectare per year and over R4.7 million (US$ 0.68 million) per commonage per year. However, the extent and nature of use and reliance was not uniform among households, so that we developed a typology of commonage users, with four types being identified. However, rapidly growing urban populations and high levels of poverty potentially threaten the sustainability of commonage resource use. Yet the national land reform programme focuses largely on the transfer of land to municipalities and not on sustainable management. Municipalities, in turn, invest relatively little in commonage management, and the little they do is focussed on livestock production. Non-timber forest products are not considered at all, even though this study shows that they are a vital resource for the urban poor, notably for energy and construction materials.
- Full Text:
- Date Issued: 2012
Can sport impact rational investor behaviour? : an evaluation of the impact of national sporting performance on stock market returns in South Africa
- Authors: De Beer, Carl Francois
- Date: 2012
- Subjects: Investments -- Psychological aspects -- Research -- South Africa Finance -- Psychological aspects -- Research -- South Africa Sports -- Economic aspects -- Research -- South Africa Sports -- Psychological aspects -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:1013 , http://hdl.handle.net/10962/d1002748
- Description: The finance industry is an extremely fast and complex world dominated by the Efficient Markets Hypothesis (EMH). This theory contains many assumptions which include that investors are rational utility maximisers and that market prices reflect all relevant economic information available to the public. However, over the years, a new form of financial literature known as behavioural finance has been gaining momentum. Behavioural finance seeks to bridge the gap between psychology and economics in an attempt to gain a better understanding of how markets react to different situations. Behavioural finance has also gained much attention in recent years due to the EMH’s inability to explain many economic anomalies. This study first considers the differences between behavioural finance theory and EMH theory before explaining how an individual’s mood has the ability to influence one’s risk taking preferences. Mood changes were also found to be linked to changes in the way an individual reacts to different situations, the way they thinks and processes thoughts. Negative events were also found to have a greater influence on an individual’s mood than positive events did, resulting in an asymmetric relationship between positive and negative results. This study then examines numerous studies indicating how non-economic events can have a statistical and significant influence on stock market returns before analysing previous literature where sport was found to influence market prices. The aim of this study is to determine if South African national sporting performance can influence investors in such a way that it has the ability to impact on market returns. Using standard event study methodology, this study determines the constant mean return using the daily All-Share price index on the JSE for the period of 1 January 1990 to 31 December 2010. This study focuses on three of South Africa’s most popular sports, namely soccer, cricket and rugby and examine if these three sports have the ability to influence market returns. Although there is some evidence of a relationship between stock returns and sporting performance in the descriptive analysis, the regression results indicate that sporting performance in South Africa does not significantly explain abnormal market returns on the JSE. The study provides a number of possible reasons for this finding and concludes by suggesting areas for future research.
- Full Text:
- Date Issued: 2012
- Authors: De Beer, Carl Francois
- Date: 2012
- Subjects: Investments -- Psychological aspects -- Research -- South Africa Finance -- Psychological aspects -- Research -- South Africa Sports -- Economic aspects -- Research -- South Africa Sports -- Psychological aspects -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:1013 , http://hdl.handle.net/10962/d1002748
- Description: The finance industry is an extremely fast and complex world dominated by the Efficient Markets Hypothesis (EMH). This theory contains many assumptions which include that investors are rational utility maximisers and that market prices reflect all relevant economic information available to the public. However, over the years, a new form of financial literature known as behavioural finance has been gaining momentum. Behavioural finance seeks to bridge the gap between psychology and economics in an attempt to gain a better understanding of how markets react to different situations. Behavioural finance has also gained much attention in recent years due to the EMH’s inability to explain many economic anomalies. This study first considers the differences between behavioural finance theory and EMH theory before explaining how an individual’s mood has the ability to influence one’s risk taking preferences. Mood changes were also found to be linked to changes in the way an individual reacts to different situations, the way they thinks and processes thoughts. Negative events were also found to have a greater influence on an individual’s mood than positive events did, resulting in an asymmetric relationship between positive and negative results. This study then examines numerous studies indicating how non-economic events can have a statistical and significant influence on stock market returns before analysing previous literature where sport was found to influence market prices. The aim of this study is to determine if South African national sporting performance can influence investors in such a way that it has the ability to impact on market returns. Using standard event study methodology, this study determines the constant mean return using the daily All-Share price index on the JSE for the period of 1 January 1990 to 31 December 2010. This study focuses on three of South Africa’s most popular sports, namely soccer, cricket and rugby and examine if these three sports have the ability to influence market returns. Although there is some evidence of a relationship between stock returns and sporting performance in the descriptive analysis, the regression results indicate that sporting performance in South Africa does not significantly explain abnormal market returns on the JSE. The study provides a number of possible reasons for this finding and concludes by suggesting areas for future research.
- Full Text:
- Date Issued: 2012
An evaluation of urban poverty and its alleviation in the Nelson Mandela Metro with special reference to prostitution as an income generator
- Authors: De Bruin, Mbulelo Douglas
- Date: 2012
- Subjects: Economic conditions -- South Africa -- Nelson Mandela Metropolitan Municipality , Poverty -- South Africa -- Nelson Mandela Metropolitan Municipality , Prostitution -- South Africa -- Nelson Mandela Metropolitan Municipality
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9001 , http://hdl.handle.net/10948/d1011663 , Economic conditions -- South Africa -- Nelson Mandela Metropolitan Municipality , Poverty -- South Africa -- Nelson Mandela Metropolitan Municipality , Prostitution -- South Africa -- Nelson Mandela Metropolitan Municipality
- Description: This paper is set to evaluate the factors leading to prostitution and provide the understanding of the hardships that are experienced by prostitutes in their pursuit for income generation. However, this will be preceded by the background to the study. Secondly, this paper will lament or touch on the strategies employed by the Nelson Mandela Metro and other countries in an attempt to alleviate poverty. Thirdly, the views of academics and other experts in the fields of both the prostitution and poverty will be put into perspective. The relevant research methodology used to this study was found to be a descriptive study. The concluding remarks and recommendations on what is needed in order to improve the situation in the Nelson Mandela Metro are provided for the purpose of this study. Towards the end of this study, bibliography has been provided followed by the relevant annexures which will serve as evidence that inform this study.
- Full Text:
- Date Issued: 2012
- Authors: De Bruin, Mbulelo Douglas
- Date: 2012
- Subjects: Economic conditions -- South Africa -- Nelson Mandela Metropolitan Municipality , Poverty -- South Africa -- Nelson Mandela Metropolitan Municipality , Prostitution -- South Africa -- Nelson Mandela Metropolitan Municipality
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9001 , http://hdl.handle.net/10948/d1011663 , Economic conditions -- South Africa -- Nelson Mandela Metropolitan Municipality , Poverty -- South Africa -- Nelson Mandela Metropolitan Municipality , Prostitution -- South Africa -- Nelson Mandela Metropolitan Municipality
- Description: This paper is set to evaluate the factors leading to prostitution and provide the understanding of the hardships that are experienced by prostitutes in their pursuit for income generation. However, this will be preceded by the background to the study. Secondly, this paper will lament or touch on the strategies employed by the Nelson Mandela Metro and other countries in an attempt to alleviate poverty. Thirdly, the views of academics and other experts in the fields of both the prostitution and poverty will be put into perspective. The relevant research methodology used to this study was found to be a descriptive study. The concluding remarks and recommendations on what is needed in order to improve the situation in the Nelson Mandela Metro are provided for the purpose of this study. Towards the end of this study, bibliography has been provided followed by the relevant annexures which will serve as evidence that inform this study.
- Full Text:
- Date Issued: 2012
The effects of sustained attention, workload and task-related fatigue on physiological measures and performance during a tracking task
- Authors: De Gray Birch, Casey
- Date: 2012
- Subjects: Fatigue -- Physiological aspects -- Research , Attention -- Physiological aspects -- Research , Human engineering -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5120 , http://hdl.handle.net/10962/d1005198 , Fatigue -- Physiological aspects -- Research , Attention -- Physiological aspects -- Research , Human engineering -- Research
- Description: Despite extensive research into the concept of mental fatigue there is as yet no “gold standard” definition or measurement technique available. Because of this a large amount of fatigue-related errors are still seen in the workplace. The complexity of the problem lies with the inability to directly measure mental processes as well as the various endogenous and exogenous factors that interact to produce the experienced fatigue. Fatigue has been divided into sleep-related and task-related fatigue; however the task-related aspect is evident both during normal waking hours as well as during periods of sleep deprivation, therefore this aspect is considered important in the understanding of fatigue in general. The concept of task-related fatigue has further been divided into active and passive fatigue states; however differentiation between the two requires careful consideration. Various physiological measures have been employed in an attempt to gain a better understanding of the mechanisms involved in the generation of fatigue, however often studies have produced dissociating results. The current study considered the task-related fatigue elicited by a tracking task requiring sustained attention, in order to evaluate the usefulness of various cardiovascular and oculomotor measures as indicators of fatigue. A secondary aim was to determine whether the behavioural and physiological parameter responses could be used to infer the type of fatigue incurred (i.e. an active versus passive fatigue state) as well as the energetical mechanisms involved during task performance. A simple driving simulator task was used as the main tracking task, requiring constant attention and concentration. This task was performed for approximately two hours. Three experimental groups (consisting of 14 subjects each) were used: a control group that performed the tracking task only, a group that performed a five minute auditory memory span task concurrently with the driving task after every 20 minutes of pure driving, and a group that performed a visual choice reaction task for five minutes following every 20 minute driving period. The secondary tasks were employed in order to evaluate the extent of resource allocation as well as arousal level. Performance measures included various driving performance parameters, as well as secondary task performance. Physiological measures included heart rate frequency (HR) and various time- and frequency-domain heart rate variability (HRV)parameters, pupil dilation, blink frequency and duration, fixations, and saccadic parameters as well as critical flicker fusion frequency (CFFF). The Borg CR-10 scale was used to evaluate subjective fatigue during the task, and the NASA-TLX was completed following the task. A decline in driving performance over time was supplemented by measures such as HR, HRV and pupil dilation indicating an increase in parasympathetic activity (or a reduction in arousal). An increase in blink frequency was considered as a sign of withdrawal of attentional resources over time. Longer and faster saccades were also evident over time, coupled with shorter fixations. With regards to the secondary task influence, the choice RT task did not affect any behavioural or physiological parameters, thereby contesting the active fatigue theory of resource depletion, as well as implying that the increase in demand for the same resources used by the primary task was insufficient to affect the state of the subjects. The increased load elicited by the memory span task improved driving performance and increased measures of HR, HRV, pupil dilation and blink frequency. Some of these measures produced opposite effects to what was expected; an attempt to explain the dissociation of the various physiological parameters was expressed in terms of arousal, effort and resource theories. Overall, the results indicate that the fatigue and/or reduced arousal accompanying a monotonous sustained attention task can, to some degree, be alleviated through intermittent performance of a secondary task engaging mental resources other than the ones used for the primary task. The degree to which such a task is beneficial, however, requires careful consideration as while an immediate increase in arousal and primary task performance is noted, the impact of the task on general attentional resources may be detrimental in the case of reacting should an emergency situation occur.
- Full Text:
- Date Issued: 2012
- Authors: De Gray Birch, Casey
- Date: 2012
- Subjects: Fatigue -- Physiological aspects -- Research , Attention -- Physiological aspects -- Research , Human engineering -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5120 , http://hdl.handle.net/10962/d1005198 , Fatigue -- Physiological aspects -- Research , Attention -- Physiological aspects -- Research , Human engineering -- Research
- Description: Despite extensive research into the concept of mental fatigue there is as yet no “gold standard” definition or measurement technique available. Because of this a large amount of fatigue-related errors are still seen in the workplace. The complexity of the problem lies with the inability to directly measure mental processes as well as the various endogenous and exogenous factors that interact to produce the experienced fatigue. Fatigue has been divided into sleep-related and task-related fatigue; however the task-related aspect is evident both during normal waking hours as well as during periods of sleep deprivation, therefore this aspect is considered important in the understanding of fatigue in general. The concept of task-related fatigue has further been divided into active and passive fatigue states; however differentiation between the two requires careful consideration. Various physiological measures have been employed in an attempt to gain a better understanding of the mechanisms involved in the generation of fatigue, however often studies have produced dissociating results. The current study considered the task-related fatigue elicited by a tracking task requiring sustained attention, in order to evaluate the usefulness of various cardiovascular and oculomotor measures as indicators of fatigue. A secondary aim was to determine whether the behavioural and physiological parameter responses could be used to infer the type of fatigue incurred (i.e. an active versus passive fatigue state) as well as the energetical mechanisms involved during task performance. A simple driving simulator task was used as the main tracking task, requiring constant attention and concentration. This task was performed for approximately two hours. Three experimental groups (consisting of 14 subjects each) were used: a control group that performed the tracking task only, a group that performed a five minute auditory memory span task concurrently with the driving task after every 20 minutes of pure driving, and a group that performed a visual choice reaction task for five minutes following every 20 minute driving period. The secondary tasks were employed in order to evaluate the extent of resource allocation as well as arousal level. Performance measures included various driving performance parameters, as well as secondary task performance. Physiological measures included heart rate frequency (HR) and various time- and frequency-domain heart rate variability (HRV)parameters, pupil dilation, blink frequency and duration, fixations, and saccadic parameters as well as critical flicker fusion frequency (CFFF). The Borg CR-10 scale was used to evaluate subjective fatigue during the task, and the NASA-TLX was completed following the task. A decline in driving performance over time was supplemented by measures such as HR, HRV and pupil dilation indicating an increase in parasympathetic activity (or a reduction in arousal). An increase in blink frequency was considered as a sign of withdrawal of attentional resources over time. Longer and faster saccades were also evident over time, coupled with shorter fixations. With regards to the secondary task influence, the choice RT task did not affect any behavioural or physiological parameters, thereby contesting the active fatigue theory of resource depletion, as well as implying that the increase in demand for the same resources used by the primary task was insufficient to affect the state of the subjects. The increased load elicited by the memory span task improved driving performance and increased measures of HR, HRV, pupil dilation and blink frequency. Some of these measures produced opposite effects to what was expected; an attempt to explain the dissociation of the various physiological parameters was expressed in terms of arousal, effort and resource theories. Overall, the results indicate that the fatigue and/or reduced arousal accompanying a monotonous sustained attention task can, to some degree, be alleviated through intermittent performance of a secondary task engaging mental resources other than the ones used for the primary task. The degree to which such a task is beneficial, however, requires careful consideration as while an immediate increase in arousal and primary task performance is noted, the impact of the task on general attentional resources may be detrimental in the case of reacting should an emergency situation occur.
- Full Text:
- Date Issued: 2012
Identification of novel marine algal compounds with differential anti-cancer activity: towards a cancer stem-cell specific chemotherapy
- Authors: De la Mare, Jo-Anne
- Date: 2012
- Subjects: Breast -- Cancer , Stem cells -- Research , Chemotherapy , Algae -- Biotechnology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4143 , http://hdl.handle.net/10962/d1016250
- Description: Breast cancer remains the leading cause of cancer-related death in women worldwide. Furthermore, it has been demonstrated that the treatment-resistant ER-PR-HER2/neu- sub-type is more common among women of African descent, necessitating the search for novel chemotherapies for this form of the disease. The secondary metabolites produced by marine algae represent a rich source of structurally unique compounds with chemotherapeutic potential, particularly in South Africa, whose oceans allegedly host 15 % of the total number of species in the world. Indeed, a recent study reported the isolation of a range of novel compounds from South African red and brown algae of the Plocamium, Portiera and Sargassum genera which displayed cytotoxicity against oesophageal cancer cells in vitro. The molecular mechanisms mediating this toxicity were unknown, as was the effect of these and similar compounds on metastatic ER-PR-HER2/neu- breast cancer cell lines or breast cancer stem cells. The current study aimed to address these questions by screening a library of twenty-two novel marine algal compounds for the ability to inhibit MDA-MB-231 and Hs578T breast cancer cells, while having no adverse effects on non-cancerous MCF12A breast epithelial cells. While twelve of these were toxic in the micromolar range against breast cancer cells, only the polyhalogenated monoterpenes RU004 and RU007, and the tetraprenylated quinone sargaquinoic acid (SQA) were identified as hit compounds based on the criteria that their cytotoxicity was specific to breast cancer and not healthy breast cells in vitro. On the other hand, the halogenated monoterpene RU015 was found to be highly toxic to both breast cancer and non-cancerous breast cell lines, while the halogenated monoterpene stereoisomers RU017 and RU018 were non-toxic to either of these cell lines. The mode of action of RU004, RU007, RU015 and SQA, together with the previously characterized carotenoid fucoxanthin (FXN), was assessed in terms of the type of cell death induced and the effect on cell cycle distribution of these compounds. Flow cytometric analysis of the extent of Hoescht 33342 and propidium iodide staining along with PARP cleavage studies suggested that SQA induced apoptosis in MDA-MB-231 cells. On the other hand, the highly toxic compound RU015 appeared to induce necrosis as evidenced by 50 kDa PARP cleavage product in MDA-MB-231 cells. The flow cytometry profiles of MDA-MB-231 and Hst578T cells treated with the hit compounds RU004 and RU007 were suggestive of the induction of apoptosis by these compounds. Cell cycle analysis by flow cytometry with propidium iodide staining revealed that both SQA and FXN induced G0-G1 arrest together with an increase in the apoptotic sub-G0 population, which agreed with previous reports in the literature. The molecular mechanism of action of SQA and FXN were further investigated by the identification of specific signal transducer molecules involved in mediating their anti-cancer activities. SQA was found to require the activity of numerous caspases, including caspase-3, -6, -8, -9, -10 and -13, for its cytotoxicity and was demonstrated to decrease the level of the antiapoptotic protein Bcl-2. On the other hand, FXN was shown to require caspase-1, -2, -3, -9 and - 10 for its toxicity. This, together with the ability to decrease the levels of Bcl-2, pointed to the involvement of the intrinsic pathway in particular in mediating the activity of FXN. The screening of algal compounds against non-cancerous breast epithelial cells carried out in this study, together with the investigation into their mechanisms of action, represent one of the few reports in which characterization of algal metabolites goes beyond the initial cytotoxicity assays. Finally, in order to assess the potential anti-cancer stem cell activity of the marine algal compounds, a subset of these was screened using a mammosphere assay technique developed in this study. The cancer stem cell (CSC) theory proposes that cancers arise from and are maintained by a specific subpopulation of cells able to undergo asymmetric cell division and termed CSCs. These CSCs are capable of anchorage-independent growth in serum-free culture conditions, such as those in the mammosphere assay. Using this assay, the novel halogenated monoterpene stereoisomers RU017 and RU018 were demonstrated to possess putative anti- CSC activity as evidenced by their ability to completely eliminate mammosphere formation in vitro. Furthermore, since RU017 and RU018 were non-toxic to both breast cancer and healthy breast cells, it appeared that the activity of the compounds was potentially specific to the CSCs. The results require further validation, but represent the first report of selective anti-CSC activity.
- Full Text:
- Date Issued: 2012
- Authors: De la Mare, Jo-Anne
- Date: 2012
- Subjects: Breast -- Cancer , Stem cells -- Research , Chemotherapy , Algae -- Biotechnology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4143 , http://hdl.handle.net/10962/d1016250
- Description: Breast cancer remains the leading cause of cancer-related death in women worldwide. Furthermore, it has been demonstrated that the treatment-resistant ER-PR-HER2/neu- sub-type is more common among women of African descent, necessitating the search for novel chemotherapies for this form of the disease. The secondary metabolites produced by marine algae represent a rich source of structurally unique compounds with chemotherapeutic potential, particularly in South Africa, whose oceans allegedly host 15 % of the total number of species in the world. Indeed, a recent study reported the isolation of a range of novel compounds from South African red and brown algae of the Plocamium, Portiera and Sargassum genera which displayed cytotoxicity against oesophageal cancer cells in vitro. The molecular mechanisms mediating this toxicity were unknown, as was the effect of these and similar compounds on metastatic ER-PR-HER2/neu- breast cancer cell lines or breast cancer stem cells. The current study aimed to address these questions by screening a library of twenty-two novel marine algal compounds for the ability to inhibit MDA-MB-231 and Hs578T breast cancer cells, while having no adverse effects on non-cancerous MCF12A breast epithelial cells. While twelve of these were toxic in the micromolar range against breast cancer cells, only the polyhalogenated monoterpenes RU004 and RU007, and the tetraprenylated quinone sargaquinoic acid (SQA) were identified as hit compounds based on the criteria that their cytotoxicity was specific to breast cancer and not healthy breast cells in vitro. On the other hand, the halogenated monoterpene RU015 was found to be highly toxic to both breast cancer and non-cancerous breast cell lines, while the halogenated monoterpene stereoisomers RU017 and RU018 were non-toxic to either of these cell lines. The mode of action of RU004, RU007, RU015 and SQA, together with the previously characterized carotenoid fucoxanthin (FXN), was assessed in terms of the type of cell death induced and the effect on cell cycle distribution of these compounds. Flow cytometric analysis of the extent of Hoescht 33342 and propidium iodide staining along with PARP cleavage studies suggested that SQA induced apoptosis in MDA-MB-231 cells. On the other hand, the highly toxic compound RU015 appeared to induce necrosis as evidenced by 50 kDa PARP cleavage product in MDA-MB-231 cells. The flow cytometry profiles of MDA-MB-231 and Hst578T cells treated with the hit compounds RU004 and RU007 were suggestive of the induction of apoptosis by these compounds. Cell cycle analysis by flow cytometry with propidium iodide staining revealed that both SQA and FXN induced G0-G1 arrest together with an increase in the apoptotic sub-G0 population, which agreed with previous reports in the literature. The molecular mechanism of action of SQA and FXN were further investigated by the identification of specific signal transducer molecules involved in mediating their anti-cancer activities. SQA was found to require the activity of numerous caspases, including caspase-3, -6, -8, -9, -10 and -13, for its cytotoxicity and was demonstrated to decrease the level of the antiapoptotic protein Bcl-2. On the other hand, FXN was shown to require caspase-1, -2, -3, -9 and - 10 for its toxicity. This, together with the ability to decrease the levels of Bcl-2, pointed to the involvement of the intrinsic pathway in particular in mediating the activity of FXN. The screening of algal compounds against non-cancerous breast epithelial cells carried out in this study, together with the investigation into their mechanisms of action, represent one of the few reports in which characterization of algal metabolites goes beyond the initial cytotoxicity assays. Finally, in order to assess the potential anti-cancer stem cell activity of the marine algal compounds, a subset of these was screened using a mammosphere assay technique developed in this study. The cancer stem cell (CSC) theory proposes that cancers arise from and are maintained by a specific subpopulation of cells able to undergo asymmetric cell division and termed CSCs. These CSCs are capable of anchorage-independent growth in serum-free culture conditions, such as those in the mammosphere assay. Using this assay, the novel halogenated monoterpene stereoisomers RU017 and RU018 were demonstrated to possess putative anti- CSC activity as evidenced by their ability to completely eliminate mammosphere formation in vitro. Furthermore, since RU017 and RU018 were non-toxic to both breast cancer and healthy breast cells, it appeared that the activity of the compounds was potentially specific to the CSCs. The results require further validation, but represent the first report of selective anti-CSC activity.
- Full Text:
- Date Issued: 2012
Quinones and halogenated monoterpenes of algal origin show anti-proliferative effects against breast cancer cells in vitro:
- de la Mare, Jo-Anne, Lawson, Jessica C, Chiwakata, Maynard T, Beukes, Denzil R, Blatch, Gregory L, Edkins, Adrienne L
- Authors: de la Mare, Jo-Anne , Lawson, Jessica C , Chiwakata, Maynard T , Beukes, Denzil R , Blatch, Gregory L , Edkins, Adrienne L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165165 , vital:41214 , DOI: 10.1007/s10637-011-9788-0
- Description: Red and brown algae have been shown to produce a variety of compounds with chemotherapeutic potential. A recent report described the isolation of a range of novel polyhalogenated monoterpene compounds from the red algae Plocamium corallorhiza and Plocamium cornutum collected off the coast of South Africa, together with the previously described tetraprenylquinone, sargaquinoic acid (SQA), from the brown algae Sargassum heterophyllum. In our study, the algal compounds were screened for anti-proliferative activity against metastatic MDA-MB-231 breast cancer cells revealing that a number of compounds displayed anti-cancer activity with IC50 values in the micromolar range. A subset of the compounds was tested for differential toxicity in the MCF-7/MCF12A system and five of these, including sargaquinoic acid, were found to be at least three times more toxic to the breast cancer than the non-malignant cell line.
- Full Text:
- Date Issued: 2012
- Authors: de la Mare, Jo-Anne , Lawson, Jessica C , Chiwakata, Maynard T , Beukes, Denzil R , Blatch, Gregory L , Edkins, Adrienne L
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165165 , vital:41214 , DOI: 10.1007/s10637-011-9788-0
- Description: Red and brown algae have been shown to produce a variety of compounds with chemotherapeutic potential. A recent report described the isolation of a range of novel polyhalogenated monoterpene compounds from the red algae Plocamium corallorhiza and Plocamium cornutum collected off the coast of South Africa, together with the previously described tetraprenylquinone, sargaquinoic acid (SQA), from the brown algae Sargassum heterophyllum. In our study, the algal compounds were screened for anti-proliferative activity against metastatic MDA-MB-231 breast cancer cells revealing that a number of compounds displayed anti-cancer activity with IC50 values in the micromolar range. A subset of the compounds was tested for differential toxicity in the MCF-7/MCF12A system and five of these, including sargaquinoic acid, were found to be at least three times more toxic to the breast cancer than the non-malignant cell line.
- Full Text:
- Date Issued: 2012
Guidelines to establish an e-safety awareness in South Africa
- Authors: De Lange, Mariska
- Date: 2012
- Subjects: Internet and children--Safety measures , Internet in education , Online etiquette
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9747 , http://hdl.handle.net/10948/d1007863 , Internet and children--Safety measures , Internet in education , Online etiquette
- Description: Information and Communication Technology (ICT) has become an integral part of almost every individual’s life. Although ICT, particularly the Internet, might offer numerous opportunities, individuals should also be aware of the associated risks. Especially with the younger generations who can be seen as being the most vulnerable to online dangers as they are becoming more involved in online activities. Children are utilizing new technologies from an early age and should know how to keep themselves and others safe whilst accessing the Internet. However, most of them do not have the required knowledge and expertise to protect themselves. This is because, under most circumstances, the parents do not understand their children’s online behaviours and activities and are, therefore, unable to teach their children how to utilize it safe and responsibly. A school can be seen as the perfect place to teach children safe online behaviours. However, there is currently a definite lack of e-Safety in South African schools, because no e-Safety policies are in place and there is little or nothing in curricula with regards to e-Safety. This can lead to additional concerns. The primary objective of this research study is, therefore, to develop, motivate and verify a framework that might contribute towards the development of an e-Safety culture. This e-Safety culture should allow individuals to adapt their behavior towards the secure utilization of ICT. However, for the purpose of this research study, the focus will primarily be on learners from primary and secondary schools.
- Full Text:
- Date Issued: 2012
- Authors: De Lange, Mariska
- Date: 2012
- Subjects: Internet and children--Safety measures , Internet in education , Online etiquette
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9747 , http://hdl.handle.net/10948/d1007863 , Internet and children--Safety measures , Internet in education , Online etiquette
- Description: Information and Communication Technology (ICT) has become an integral part of almost every individual’s life. Although ICT, particularly the Internet, might offer numerous opportunities, individuals should also be aware of the associated risks. Especially with the younger generations who can be seen as being the most vulnerable to online dangers as they are becoming more involved in online activities. Children are utilizing new technologies from an early age and should know how to keep themselves and others safe whilst accessing the Internet. However, most of them do not have the required knowledge and expertise to protect themselves. This is because, under most circumstances, the parents do not understand their children’s online behaviours and activities and are, therefore, unable to teach their children how to utilize it safe and responsibly. A school can be seen as the perfect place to teach children safe online behaviours. However, there is currently a definite lack of e-Safety in South African schools, because no e-Safety policies are in place and there is little or nothing in curricula with regards to e-Safety. This can lead to additional concerns. The primary objective of this research study is, therefore, to develop, motivate and verify a framework that might contribute towards the development of an e-Safety culture. This e-Safety culture should allow individuals to adapt their behavior towards the secure utilization of ICT. However, for the purpose of this research study, the focus will primarily be on learners from primary and secondary schools.
- Full Text:
- Date Issued: 2012