A framework for managing timetable data quality within the NMMU
- Authors: Els, Dierdre Jean
- Date: 2008
- Subjects: Computer algorithms Timetables , Management information systems , Management -- Data processing , Information storage and retrieval systems -- Management , Information management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9769 , http://hdl.handle.net/10948/948 , Computer algorithms Timetables , Management information systems , Management -- Data processing , Information storage and retrieval systems -- Management , Information management
- Description: This dissertation investigates the influencing factors on timetable quality, not only from a data quality perspective, but also from an information quality perspective which takes into account the quality of the business processes involved in creating the timetable. The Nelson Mandela Metropolitan University was used as a case study for assessing the quality of the timetable process, the quality of the source data, and the quality of the final timetable produced. A framework for managing the data quality during the timetabling process is proposed. The framework is based on reviews done on data quality management best practices and data quality aspects. Chapter 1 introduces the current Nelson Mandela Metropolitan University timetable, and motivates why data quality management is essential to its success. The scope and research objectives are presented for this dissertation. Chapter 2 covers a literature study on business process and data quality management best practices. The common thread through all the management methodologies investigated, was top management involvement and commitment to continuously improving the quality of data. Chapter 3 discusses various characteristics of data quality. Quality is determined to be whether the end result meets the quality requirements for which it was intended. Hence each system could have quality aspects that are unique to it. Chapter 4 explains various research designs and which were followed for this dissertation. The combination of literature studies, a questionnaire and a case study were used. Chapter 5 is a case study of the data quality and timetabling processes used at the Nelson Mandela Metropolitan University and is based on the research design described in chapter 4. The current business processes followed in setting up the current timetable are presented, as well as the proposed timetabling process that should produce a better quality timetable for the Nelson Mandela Metropolitan 4 University. The data quality aspects most pertinent to the Nelson Mandela Metropolitan University are determined, being timeliness, accountability, integrity and consistency, as well as the most probable causes for bad timetable quality, like uniform technology, processes, ownership and using a common terminology. Chapter 6 presents a framework for managing timetable data quality at the Nelson Mandela Metropolitan University using an Information Product Map approach that will ensure a better quality timetable. Future research is also proposed. It is evident from this dissertation that data quality of source data as well as the quality of the business process involved is essential for producing a timetable that satisfies the requirements for which it was intended. The management framework proposed for the Nelson Mandela Metropolitan University timetabling process can potentially be used at other institutions as well.
- Full Text:
- Date Issued: 2008
- Authors: Els, Dierdre Jean
- Date: 2008
- Subjects: Computer algorithms Timetables , Management information systems , Management -- Data processing , Information storage and retrieval systems -- Management , Information management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9769 , http://hdl.handle.net/10948/948 , Computer algorithms Timetables , Management information systems , Management -- Data processing , Information storage and retrieval systems -- Management , Information management
- Description: This dissertation investigates the influencing factors on timetable quality, not only from a data quality perspective, but also from an information quality perspective which takes into account the quality of the business processes involved in creating the timetable. The Nelson Mandela Metropolitan University was used as a case study for assessing the quality of the timetable process, the quality of the source data, and the quality of the final timetable produced. A framework for managing the data quality during the timetabling process is proposed. The framework is based on reviews done on data quality management best practices and data quality aspects. Chapter 1 introduces the current Nelson Mandela Metropolitan University timetable, and motivates why data quality management is essential to its success. The scope and research objectives are presented for this dissertation. Chapter 2 covers a literature study on business process and data quality management best practices. The common thread through all the management methodologies investigated, was top management involvement and commitment to continuously improving the quality of data. Chapter 3 discusses various characteristics of data quality. Quality is determined to be whether the end result meets the quality requirements for which it was intended. Hence each system could have quality aspects that are unique to it. Chapter 4 explains various research designs and which were followed for this dissertation. The combination of literature studies, a questionnaire and a case study were used. Chapter 5 is a case study of the data quality and timetabling processes used at the Nelson Mandela Metropolitan University and is based on the research design described in chapter 4. The current business processes followed in setting up the current timetable are presented, as well as the proposed timetabling process that should produce a better quality timetable for the Nelson Mandela Metropolitan 4 University. The data quality aspects most pertinent to the Nelson Mandela Metropolitan University are determined, being timeliness, accountability, integrity and consistency, as well as the most probable causes for bad timetable quality, like uniform technology, processes, ownership and using a common terminology. Chapter 6 presents a framework for managing timetable data quality at the Nelson Mandela Metropolitan University using an Information Product Map approach that will ensure a better quality timetable. Future research is also proposed. It is evident from this dissertation that data quality of source data as well as the quality of the business process involved is essential for producing a timetable that satisfies the requirements for which it was intended. The management framework proposed for the Nelson Mandela Metropolitan University timetabling process can potentially be used at other institutions as well.
- Full Text:
- Date Issued: 2008
Cranial ontogeny of the sole, dagetichthys marginatus (soleidae), with considerations on the feeding ability of larvae and early juveniles
- Ende, Stephan Siegfried Werner
- Authors: Ende, Stephan Siegfried Werner
- Date: 2008
- Subjects: Soleidae , Fishes -- Larvae -- Food , Flatfishes -- Nutrition , Artemia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5250 , http://hdl.handle.net/10962/d1005093 , Soleidae , Fishes -- Larvae -- Food , Flatfishes -- Nutrition , Artemia
- Description: The overall aim of this study was to gain a better understanding of the feeding mechanisms of the larvae and early juveniles of the sole, Dagetichthys marginatus (Soleidae), with which to assess the suitability of current feeding protocols and to facilitate the development of an appropriate pelleted feed. This was achieved by examining the ontogeny of the cranium of laboratory reared sole, with particular emphasis on those elements associated with feeding and by comparing the cranium of juvenile fish with that of adult fish. At 4 dah (days after hatch) Dagetichthys marginatus larvae develop the first rudimentary branchial arches that facilitates the capture and ingestion of food items. Subsequent development of cranial structures, such as the oral jaws, suspensorium, neurocranium, hyoid and branchial arches and the opercular apparatus enables the larvae, at 16 dah, to switch from ram feeding to suction feeding on live prey. The use of live Artemia nauplii from 4 to 16 dah is therefore appropriate. The first morphological asymmetries developed at 16 dah in the dentaries and at 22 dah the maxillae and the premaxillae began to show asymmetries. Teeth were present only on the blind side of the oral jaw elements and during this period (16 to 22 dah) the existing elements began to ossify. From 16 to 35 dah the standard feeding protocol consists of a combination of pelagic (Artemia metanauplii) and benthic prey (dead, frozen Artemia nauplii) and from 25 dah onwards a sinking pellet is provided. The time (dah) at which frozen Artemia and sinking pellets were provided, appropriately corresponded to the initiation of benthic feeding behaviour. However at this stage the use of pelagic Artemia metanauplii is inappropriate and unnecessary. At 31 dah the cranial morphology resembled that of adult fish. Adult D. marginatus display extreme asymmetries among the elements of the oral jaws, the suspensorium and certain elements of the neurocranium. Elements on the blind side are larger and more robust than those on the ocular side and are adapted for feeding, while those on the ocular side appear to have a respiratory function. From 31 dah the cranial elements are identical to those of adult fish, suggesting that no further feeding behavioural changes occurred and that a sinking pellet, of which the nutrient composition meets the requirements of the fish, would be appropriate for ongrowing.
- Full Text:
- Date Issued: 2008
- Authors: Ende, Stephan Siegfried Werner
- Date: 2008
- Subjects: Soleidae , Fishes -- Larvae -- Food , Flatfishes -- Nutrition , Artemia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5250 , http://hdl.handle.net/10962/d1005093 , Soleidae , Fishes -- Larvae -- Food , Flatfishes -- Nutrition , Artemia
- Description: The overall aim of this study was to gain a better understanding of the feeding mechanisms of the larvae and early juveniles of the sole, Dagetichthys marginatus (Soleidae), with which to assess the suitability of current feeding protocols and to facilitate the development of an appropriate pelleted feed. This was achieved by examining the ontogeny of the cranium of laboratory reared sole, with particular emphasis on those elements associated with feeding and by comparing the cranium of juvenile fish with that of adult fish. At 4 dah (days after hatch) Dagetichthys marginatus larvae develop the first rudimentary branchial arches that facilitates the capture and ingestion of food items. Subsequent development of cranial structures, such as the oral jaws, suspensorium, neurocranium, hyoid and branchial arches and the opercular apparatus enables the larvae, at 16 dah, to switch from ram feeding to suction feeding on live prey. The use of live Artemia nauplii from 4 to 16 dah is therefore appropriate. The first morphological asymmetries developed at 16 dah in the dentaries and at 22 dah the maxillae and the premaxillae began to show asymmetries. Teeth were present only on the blind side of the oral jaw elements and during this period (16 to 22 dah) the existing elements began to ossify. From 16 to 35 dah the standard feeding protocol consists of a combination of pelagic (Artemia metanauplii) and benthic prey (dead, frozen Artemia nauplii) and from 25 dah onwards a sinking pellet is provided. The time (dah) at which frozen Artemia and sinking pellets were provided, appropriately corresponded to the initiation of benthic feeding behaviour. However at this stage the use of pelagic Artemia metanauplii is inappropriate and unnecessary. At 31 dah the cranial morphology resembled that of adult fish. Adult D. marginatus display extreme asymmetries among the elements of the oral jaws, the suspensorium and certain elements of the neurocranium. Elements on the blind side are larger and more robust than those on the ocular side and are adapted for feeding, while those on the ocular side appear to have a respiratory function. From 31 dah the cranial elements are identical to those of adult fish, suggesting that no further feeding behavioural changes occurred and that a sinking pellet, of which the nutrient composition meets the requirements of the fish, would be appropriate for ongrowing.
- Full Text:
- Date Issued: 2008
Investigating the potential for the application of lean manufacturing in the can coating plant at Duco Coatings
- Authors: Erasmus, Deidre Felicia
- Date: 2008
- Subjects: Manufacturing processes -- South Africa , Waste minimization -- South Africa , Production management -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8579 , http://hdl.handle.net/10948/949 , Manufacturing processes -- South Africa , Waste minimization -- South Africa , Production management -- South Africa
- Description: Companies are constantly expected to be more competitive while working in an environment in which time and cost are limited, thereby preventing such companies from taking the time required to be responsive. It is, therefore, important that companies understand that conventional knowledge and methods will not serve unless there is a concerted focus on improvement of organisational performance toward fulfilling increased expectations, not just maintaining that which is comfortable. A more sustainable approach may be the introduction of lean manufacturing techniques. The lean manufacturing process is one that continuously strives to eliminate waste, thereby increasing the percentage of time that may be devoted to value-adding activities. Lean manufacturing principles were applied in the Can Coating Plant of Duco Speciality Coatings. This study was intended to identify waste in the current production process in the Can Coating Plant and then to use lean tools and principles to eliminate such waste. Implementation of these lean tools proved to result in a leaner and more value-adding process. The new process rendered a positive result on Duco Coating’s costs, quality and product performance. Recommendations on further improvements were also offered.
- Full Text:
- Date Issued: 2008
- Authors: Erasmus, Deidre Felicia
- Date: 2008
- Subjects: Manufacturing processes -- South Africa , Waste minimization -- South Africa , Production management -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8579 , http://hdl.handle.net/10948/949 , Manufacturing processes -- South Africa , Waste minimization -- South Africa , Production management -- South Africa
- Description: Companies are constantly expected to be more competitive while working in an environment in which time and cost are limited, thereby preventing such companies from taking the time required to be responsive. It is, therefore, important that companies understand that conventional knowledge and methods will not serve unless there is a concerted focus on improvement of organisational performance toward fulfilling increased expectations, not just maintaining that which is comfortable. A more sustainable approach may be the introduction of lean manufacturing techniques. The lean manufacturing process is one that continuously strives to eliminate waste, thereby increasing the percentage of time that may be devoted to value-adding activities. Lean manufacturing principles were applied in the Can Coating Plant of Duco Speciality Coatings. This study was intended to identify waste in the current production process in the Can Coating Plant and then to use lean tools and principles to eliminate such waste. Implementation of these lean tools proved to result in a leaner and more value-adding process. The new process rendered a positive result on Duco Coating’s costs, quality and product performance. Recommendations on further improvements were also offered.
- Full Text:
- Date Issued: 2008
An evaluation of the questions posed to child witnesses in court to determine whether they are developmentally appropriate
- Authors: Erasmus, Ronell
- Date: 2008
- Subjects: Child witnesses -- South Africa , Law -- Language
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10267 , http://hdl.handle.net/10948/747 , Child witnesses -- South Africa , Law -- Language
- Description: Children are often required to testify viva voce in criminal trials. The question arises whether children understand what is communicated to them during their testimony in court. In the courtroom, the witness serves as a source of information. In child abuse cases in particular, the meaningful participation of the child in court proceedings is crucial due to the fact that the child is often the key witness, or the only witness, for the prosecution. The proper evaluation of the child’s evidence, however, requires that all role-players involved in the judicial process have a sound knowledge of those aspects which deal with child psychology, especially the cognitive and language abilities of children who testify. The procedure that is followed in court is not understood by the ordinary lay person, even less by children, and the language used is formalistic and very specialized. Legal language in general often contains cognitively and linguistically inappropriate questions which prevent children from relating their stories. Furthermore their responses do not sufficiently reflect their knowledge and experience of the incident of alleged sexual assault. Court language creates serious problems for children and accordingly prevents them from being effective witnesses and taking part in the judicial process in a meaningful way. The researcher, in her capacity as a Regional Court Magistrate, realized that children have limited understanding of the criminal trial process and often become secondary victims as a result of a system that does not acknowledge their cognitive and linguistic developmental levels. The purpose of this research was therefore to test the validity of the following hypotheses: • During the examination of children in a criminal trial developmentally and linguistically inappropriate questions are posed to them; and This results in ineffective communication. Eight court transcripts of criminal cases heard in the regional courts of the Eastern Cape and Mpumalanga by different presiding officers were chosen at random. These transcripts were analyzed and evaluated in order to determine whether questions posed to children when they testify are cognitively and linguistically appropriate. Each question in each of the eight transcripts was numbered and analyzed. The findings of the analysis were categorized in terms of whether they were cognitively and linguistically inappropriate questions. It was clear that the majority of questions put to the child witnesses were cognitively and linguistically inappropriate. It is evident from the evaluation that the manner in which the children’s evidence in court was presented and the way in which they were questioned created a communication barrier which placed a distorted version of events before the court. It is therefore recommended that full account be taken of the cognitive and language capabilities of each particular child in order to elicit reliable information during the child’s testimony. It is of the utmost importance that questioning be conducted in such a fashion so as to ensure that the child witness understands not only the content of the questions, but also what answers or responses are expected from them. At present, acknowledgement of linguistic and cognitive developmental appropriateness, concern and comprehension for the psychology of the child witness are ignored at best, and totally exploited at worst. This lack of knowledge about child development impacts adversely upon the child’s credibility in court. To elevate and enhance the credibility of children, it is of the utmost importance for society in general and court role-players in particular to appreciate the various stages and faces of child development. The main recommendation is that court role-players should make a paradigm shift and children, including victims of sexual assault, should be given the opportunity to tell their own stories in their own language supported by other methods of communication. In evaluating any possible changes, it is necessary to adopt and develop a holistic and multi-disciplinary approach based on scientific principles. A specialized system is required to deal with children in the criminal justice system and innovative methods to achieve this are necessary. There is a strong need to change or adjust the present manner in which the criminal justice system accommodates child witnesses. Such a change or adjustment will be in the best interests of children as envisaged in section 28 of the Constitution of the Republic of South Africa Act.
- Full Text:
- Date Issued: 2008
- Authors: Erasmus, Ronell
- Date: 2008
- Subjects: Child witnesses -- South Africa , Law -- Language
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10267 , http://hdl.handle.net/10948/747 , Child witnesses -- South Africa , Law -- Language
- Description: Children are often required to testify viva voce in criminal trials. The question arises whether children understand what is communicated to them during their testimony in court. In the courtroom, the witness serves as a source of information. In child abuse cases in particular, the meaningful participation of the child in court proceedings is crucial due to the fact that the child is often the key witness, or the only witness, for the prosecution. The proper evaluation of the child’s evidence, however, requires that all role-players involved in the judicial process have a sound knowledge of those aspects which deal with child psychology, especially the cognitive and language abilities of children who testify. The procedure that is followed in court is not understood by the ordinary lay person, even less by children, and the language used is formalistic and very specialized. Legal language in general often contains cognitively and linguistically inappropriate questions which prevent children from relating their stories. Furthermore their responses do not sufficiently reflect their knowledge and experience of the incident of alleged sexual assault. Court language creates serious problems for children and accordingly prevents them from being effective witnesses and taking part in the judicial process in a meaningful way. The researcher, in her capacity as a Regional Court Magistrate, realized that children have limited understanding of the criminal trial process and often become secondary victims as a result of a system that does not acknowledge their cognitive and linguistic developmental levels. The purpose of this research was therefore to test the validity of the following hypotheses: • During the examination of children in a criminal trial developmentally and linguistically inappropriate questions are posed to them; and This results in ineffective communication. Eight court transcripts of criminal cases heard in the regional courts of the Eastern Cape and Mpumalanga by different presiding officers were chosen at random. These transcripts were analyzed and evaluated in order to determine whether questions posed to children when they testify are cognitively and linguistically appropriate. Each question in each of the eight transcripts was numbered and analyzed. The findings of the analysis were categorized in terms of whether they were cognitively and linguistically inappropriate questions. It was clear that the majority of questions put to the child witnesses were cognitively and linguistically inappropriate. It is evident from the evaluation that the manner in which the children’s evidence in court was presented and the way in which they were questioned created a communication barrier which placed a distorted version of events before the court. It is therefore recommended that full account be taken of the cognitive and language capabilities of each particular child in order to elicit reliable information during the child’s testimony. It is of the utmost importance that questioning be conducted in such a fashion so as to ensure that the child witness understands not only the content of the questions, but also what answers or responses are expected from them. At present, acknowledgement of linguistic and cognitive developmental appropriateness, concern and comprehension for the psychology of the child witness are ignored at best, and totally exploited at worst. This lack of knowledge about child development impacts adversely upon the child’s credibility in court. To elevate and enhance the credibility of children, it is of the utmost importance for society in general and court role-players in particular to appreciate the various stages and faces of child development. The main recommendation is that court role-players should make a paradigm shift and children, including victims of sexual assault, should be given the opportunity to tell their own stories in their own language supported by other methods of communication. In evaluating any possible changes, it is necessary to adopt and develop a holistic and multi-disciplinary approach based on scientific principles. A specialized system is required to deal with children in the criminal justice system and innovative methods to achieve this are necessary. There is a strong need to change or adjust the present manner in which the criminal justice system accommodates child witnesses. Such a change or adjustment will be in the best interests of children as envisaged in section 28 of the Constitution of the Republic of South Africa Act.
- Full Text:
- Date Issued: 2008
Constructing confidence intervals for polarization mode dispersion
- Authors: Erlank, Warrick
- Date: 2008
- Subjects: Fiber optics , Polarization (Light)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10571 , http://hdl.handle.net/10948/951 , Fiber optics , Polarization (Light)
- Description: Polarization mode dispersion (PMD) causes significant impairment in high bit-rate optical telecommunications systems. Knowledge of a fibre’s PMD mean value, and the relevant confidence interval, is essential for determining a fibre’s maximum allowable bit-rate. Various methods of confidence interval construction for time series data were tested in this dissertation using simulation. These included the autocovariance-matrix methods as suggested by Box and Jenkins, as well as the more practical and simpler batch means methods. Some of these methods were shown to be significantly better than the standard method of calculating confidence intervals for non time series data. The best of the tested methods were used on actual PMD data. The effect of using polarization scramblers was also tested.
- Full Text:
- Date Issued: 2008
- Authors: Erlank, Warrick
- Date: 2008
- Subjects: Fiber optics , Polarization (Light)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10571 , http://hdl.handle.net/10948/951 , Fiber optics , Polarization (Light)
- Description: Polarization mode dispersion (PMD) causes significant impairment in high bit-rate optical telecommunications systems. Knowledge of a fibre’s PMD mean value, and the relevant confidence interval, is essential for determining a fibre’s maximum allowable bit-rate. Various methods of confidence interval construction for time series data were tested in this dissertation using simulation. These included the autocovariance-matrix methods as suggested by Box and Jenkins, as well as the more practical and simpler batch means methods. Some of these methods were shown to be significantly better than the standard method of calculating confidence intervals for non time series data. The best of the tested methods were used on actual PMD data. The effect of using polarization scramblers was also tested.
- Full Text:
- Date Issued: 2008
Melanie Klein: a psychobiographical study
- Authors: Espinosa, Marianna J
- Date: 2008
- Subjects: Klein, Melanie Psychology -- Biographical methods Psychoanalysis
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2971 , http://hdl.handle.net/10962/d1002480
- Description: The objective of psychobiography is a better understanding of individuals, and psychobiographical case studies add meaning and value to research (Runyan, 1988a). Melanie Klein was chosen for this study through a purposive sampling method due to her contributions to the discipline of psychology, which placed her in a distinguished position regarding twentieth century psychoanalysis. Furthermore, no other psychobiography has been written on Klein. The primary aim of this study was to present the reader with a basic description of her life, and a secondary aim was to accomplish an in-depth description of Klein within her social and historical context. Due to these aims and the nature of psychobiography, it may be said that this is a qualitative study based on a single case method, described as explorative and descriptive. Data was analysed according to Huberman and Miles’ (1994) approach which consists of data reduction, display and verification. This study was guided by Levinson’s (1996) theory of Adult Development in Women. The theory allowed for an in-depth description of Klein’s experiences and social and historical contexts by merely illuminating her life. Finally, it may be said that this study contributed to the limited amount of psychobiographical research in South Africa.
- Full Text:
- Date Issued: 2008
- Authors: Espinosa, Marianna J
- Date: 2008
- Subjects: Klein, Melanie Psychology -- Biographical methods Psychoanalysis
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2971 , http://hdl.handle.net/10962/d1002480
- Description: The objective of psychobiography is a better understanding of individuals, and psychobiographical case studies add meaning and value to research (Runyan, 1988a). Melanie Klein was chosen for this study through a purposive sampling method due to her contributions to the discipline of psychology, which placed her in a distinguished position regarding twentieth century psychoanalysis. Furthermore, no other psychobiography has been written on Klein. The primary aim of this study was to present the reader with a basic description of her life, and a secondary aim was to accomplish an in-depth description of Klein within her social and historical context. Due to these aims and the nature of psychobiography, it may be said that this is a qualitative study based on a single case method, described as explorative and descriptive. Data was analysed according to Huberman and Miles’ (1994) approach which consists of data reduction, display and verification. This study was guided by Levinson’s (1996) theory of Adult Development in Women. The theory allowed for an in-depth description of Klein’s experiences and social and historical contexts by merely illuminating her life. Finally, it may be said that this study contributed to the limited amount of psychobiographical research in South Africa.
- Full Text:
- Date Issued: 2008
Patterns of risk-taking behaviour of first year university students
- Authors: Essendrup, Eugene
- Date: 2008
- Subjects: College students -- South Africa -- Social conditions , Risk-taking (Psychology)
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11851 , http://hdl.handle.net/10353/135 , College students -- South Africa -- Social conditions , Risk-taking (Psychology)
- Description: This study investigated risk-taking behaviours among 244 first year students (Male=52 and Female=192). The risk-taking behaviours of the students were grouped into Risky and Violent Behaviour, Tobacco Use, Alcohol and Drug Use, Risky Sexual Behaviour and Unhealthy Dietary Behaviour subscales. Statistically significant correlations were found among all the risk-taking behaviour subscales other than Unhealthy Dietary Behaviours, which did not correlate with the other risky behaviours. Statistical significant sex differences were found regarding risk-taking behaviour that implicated males as higher risk-takers than females.
- Full Text:
- Date Issued: 2008
- Authors: Essendrup, Eugene
- Date: 2008
- Subjects: College students -- South Africa -- Social conditions , Risk-taking (Psychology)
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11851 , http://hdl.handle.net/10353/135 , College students -- South Africa -- Social conditions , Risk-taking (Psychology)
- Description: This study investigated risk-taking behaviours among 244 first year students (Male=52 and Female=192). The risk-taking behaviours of the students were grouped into Risky and Violent Behaviour, Tobacco Use, Alcohol and Drug Use, Risky Sexual Behaviour and Unhealthy Dietary Behaviour subscales. Statistically significant correlations were found among all the risk-taking behaviour subscales other than Unhealthy Dietary Behaviours, which did not correlate with the other risky behaviours. Statistical significant sex differences were found regarding risk-taking behaviour that implicated males as higher risk-takers than females.
- Full Text:
- Date Issued: 2008
The discursive management of homework practices in three primary schools in Nelson Mandela Bay
- Authors: Felix, Nadine
- Date: 2008
- Subjects: Homework -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8464 , http://hdl.handle.net/10948/782 , Homework -- South Africa -- Port Elizabeth
- Description: This treatise examines the discursive management of homework practices in three primary schools in Nelson Mandela Bay. Grade four is focused on as it is hoped that at this stage of their schooling, the learners are receiving homework and are familiar with the concept. The three schools are from differing social, historical, political and economic backgrounds. The schools chosen are a former model C school, a ‘Coloured’ school and a ‘Township’ school. These three diverse schools have been selected to identify the dominant Discourses that inform the homework practices. The eventual effect of these Discourses on the learners is also included. The material and personal effects on the learners is discussed. The prevalent Discourses on homework in the model C school, work to produce disciplined subjects who are able to ‘self govern’ and thereby succeed in society. At school’s B and C the dominant Discourses are of a deficit nature. These discursively position the learners as victims and subjects who are unable to manage their academic and private selves, as a result of their circumstance. While the staffs at schools B and C appear to be well intentioned, this abovementioned deficit model is perpetuated by their talk. These principals and teachers need to become aware of the power that their discursive formations contain and the impact thereof. A qualitative methodology is adopted in this study. Three different methods of data collection are employed in order to promote triangulation and thereby increase the validity of the findings. Discourse and Critical Discourse analysis provide the tools with which to analyse and draw conclusions from the gathered data.
- Full Text:
- Date Issued: 2008
- Authors: Felix, Nadine
- Date: 2008
- Subjects: Homework -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8464 , http://hdl.handle.net/10948/782 , Homework -- South Africa -- Port Elizabeth
- Description: This treatise examines the discursive management of homework practices in three primary schools in Nelson Mandela Bay. Grade four is focused on as it is hoped that at this stage of their schooling, the learners are receiving homework and are familiar with the concept. The three schools are from differing social, historical, political and economic backgrounds. The schools chosen are a former model C school, a ‘Coloured’ school and a ‘Township’ school. These three diverse schools have been selected to identify the dominant Discourses that inform the homework practices. The eventual effect of these Discourses on the learners is also included. The material and personal effects on the learners is discussed. The prevalent Discourses on homework in the model C school, work to produce disciplined subjects who are able to ‘self govern’ and thereby succeed in society. At school’s B and C the dominant Discourses are of a deficit nature. These discursively position the learners as victims and subjects who are unable to manage their academic and private selves, as a result of their circumstance. While the staffs at schools B and C appear to be well intentioned, this abovementioned deficit model is perpetuated by their talk. These principals and teachers need to become aware of the power that their discursive formations contain and the impact thereof. A qualitative methodology is adopted in this study. Three different methods of data collection are employed in order to promote triangulation and thereby increase the validity of the findings. Discourse and Critical Discourse analysis provide the tools with which to analyse and draw conclusions from the gathered data.
- Full Text:
- Date Issued: 2008
Cross-cultural normative indicators on the Wechsler Memory Scale (WMS) associate learning and visual reproduction subtests
- Authors: Fike, Lauren
- Date: 2008
- Subjects: Wechsler Memory Scale -- Cross-cultural studies Memory -- Testing Memory -- Cross-cultural studies Memory Assessment Scales Short-term memory -- Testing Long-term memory -- Testing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2975 , http://hdl.handle.net/10962/d1002484
- Description: A comprehensive battery of commonly used neuropsychological tests, including the WMS Associate Learning and Visual Reproduction subtests, forming the focus of this study, were administered to a southern African sample (n = 33, age range 18-40). This sample composed of black South African, IsiXhosa speakers with an educational level of Grade 11 and 12, derived through DET and former DET schooling. The gender demographics were as follows; females n = 21 and males n = 12. This sample was purposefully selected based on current cross-cultural research which suggests that individuals matching these above-mentioned demographics are significantly disadvantaged when compared to available neuropsychological norms. This is due to the fact that current norms have been created in contexts with socio-cultural influences; including culture, language and quantity and quality of education distinctly dissimilar to individuals like that composed in the sample. Hence the purpose of this study was fourfold namely; 1) Describe and consider socio-cultural factors and the influence on test performance 2) Provide descriptive and preliminary normative data on this neuropsychologically underrepresented population 3) Compare test performance between age and gender through stratification of the sample and finally to 4) Evaluate the current norms of the two WMS subtests and assess their validity for black South Africans with DET and former DET schooling with comparisons to the results found in the study. Information derived from the statistical analyses indicated that a higher performance in favour of the younger group over the older age range was consistently found for both WMS subtests. With regards to gender, some higher means were evident for the male population in the sample than was produced by the female group. Lastly, due to the fact that most scores derived from the sample were considerably lower when compared to the available norms, it is felt that socio-cultural factors prevalent to this population are a significant cause of lower test performance and thus warrant the development of appropriate normative indicators.
- Full Text:
- Date Issued: 2008
- Authors: Fike, Lauren
- Date: 2008
- Subjects: Wechsler Memory Scale -- Cross-cultural studies Memory -- Testing Memory -- Cross-cultural studies Memory Assessment Scales Short-term memory -- Testing Long-term memory -- Testing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2975 , http://hdl.handle.net/10962/d1002484
- Description: A comprehensive battery of commonly used neuropsychological tests, including the WMS Associate Learning and Visual Reproduction subtests, forming the focus of this study, were administered to a southern African sample (n = 33, age range 18-40). This sample composed of black South African, IsiXhosa speakers with an educational level of Grade 11 and 12, derived through DET and former DET schooling. The gender demographics were as follows; females n = 21 and males n = 12. This sample was purposefully selected based on current cross-cultural research which suggests that individuals matching these above-mentioned demographics are significantly disadvantaged when compared to available neuropsychological norms. This is due to the fact that current norms have been created in contexts with socio-cultural influences; including culture, language and quantity and quality of education distinctly dissimilar to individuals like that composed in the sample. Hence the purpose of this study was fourfold namely; 1) Describe and consider socio-cultural factors and the influence on test performance 2) Provide descriptive and preliminary normative data on this neuropsychologically underrepresented population 3) Compare test performance between age and gender through stratification of the sample and finally to 4) Evaluate the current norms of the two WMS subtests and assess their validity for black South Africans with DET and former DET schooling with comparisons to the results found in the study. Information derived from the statistical analyses indicated that a higher performance in favour of the younger group over the older age range was consistently found for both WMS subtests. With regards to gender, some higher means were evident for the male population in the sample than was produced by the female group. Lastly, due to the fact that most scores derived from the sample were considerably lower when compared to the available norms, it is felt that socio-cultural factors prevalent to this population are a significant cause of lower test performance and thus warrant the development of appropriate normative indicators.
- Full Text:
- Date Issued: 2008
An evaluation of the constitutionality of the common law crime of criminal defamation
- Authors: Fischer, Carl Frederich
- Date: 2008
- Subjects: Libel and slander -- South Africa , Common law -- Evaluation , Criminal law -- South Africa , Criminal procedure -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10171 , http://hdl.handle.net/10948/749 , Libel and slander -- South Africa , Common law -- Evaluation , Criminal law -- South Africa , Criminal procedure -- South Africa
- Description: The challenge in the law of defamation lies in finding the appropriate balance between the two competing rights of freedom of expression and an unimpaired reputation. From Roman and Roman-Dutch law into the modern era, criminal and civil defamation have been very closely linked. The elements and defences are substantially alike. There were several calls prior to 1994 for the abrogation of criminal defamation. Now that the right to an unimpaired reputation, as part of the right to human dignity, and the right to freedom of expression is constitutionally guaranteed, quo vadis the crime of criminal defamation? The Supreme Court of Appeal has recently granted a petition for leave to appeal against convictions for criminal defamation on this very point: is the offence constitutional. Due to the paucity of criminal defamation precedent, the copious civil law precedent concerning civil defamation must be analysed to determine what view the Supreme Court of Appeal will adopt. Prior to 1994 the right to an unimpaired reputation has trumped freedom of expression. Since then, the two leading decisions by the Supreme Court of Appeal and the Constitutional Court have ameliorated this situation slightly, according freedom of expression more weight. Claiming the previous common law position was incorrect, they claim the present common law position is constitutionally sound. Thus the Constitution has in essence had no effect to date upon the balancing of competing rights in the law of defamation. Both courts have erred in according the right to freedom of expression too little weight. This may be due to three judicial errors. Firstly, they have under-appreciated that the values of dignity, equality and freedom fortify and are fortified by the right to freedom of expression. Aspects of dignity such as self-actualisation, self-governance and an acceptance that humans have intrinsic worth are heavily reliant on freedom of expression, particularly political expression. Secondly, while political expression lies at the core of freedom of expression, reputation lies nearer the periphery of the right to dignity. Rights at the core ought to trump competing but peripheral rights. Thirdly, erroneous statements are inevitable in free debate. Unless they too are protected, unacceptable self-censorship occurs. The correct approach is as a matter of policy, particularly regarding political expression, to balance the competing rights with one’s thumb on the free expression side of the scales. This seems the trend of the European Court of Human Rights in recent cases In Canada, an offence punishing libel made intentionally but without knowledge of its falsity was recently ruled unconstitutional. On the other hand, another offence punishing libel made with knowledge it was false, videlicet punishing the intentional publication of defamatory lies, was ruled constitutional. Criminal defamation clearly infringes upon the right to freedom of expression. For this infringement to pass constitutional muster it must be reasonable and justifiable in an open and democratic society. It fails the limitation test due to the lack of proportionality between its objective in protecting the right to an unimpaired reputation and the harm it does to the right to expression. There are three reasons: firstly the “chilling effect” of imprisonment, over and above pecuniary damages, unacceptably stifles free debate. Secondly, it may punish even the truth, yet protect a falsehood, since the truth per se is not a defence. An undeserved reputation is thus more highly valued than the publication of that truth. Finally there is a well-developed civil remedy that adequately protects the right to reputation of aggrieved persons. In the appeal concerning the constitutionality of the common law offence of criminal defamation, the Supreme Court of Appeal ought to find it unconstitutional.
- Full Text:
- Date Issued: 2008
- Authors: Fischer, Carl Frederich
- Date: 2008
- Subjects: Libel and slander -- South Africa , Common law -- Evaluation , Criminal law -- South Africa , Criminal procedure -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10171 , http://hdl.handle.net/10948/749 , Libel and slander -- South Africa , Common law -- Evaluation , Criminal law -- South Africa , Criminal procedure -- South Africa
- Description: The challenge in the law of defamation lies in finding the appropriate balance between the two competing rights of freedom of expression and an unimpaired reputation. From Roman and Roman-Dutch law into the modern era, criminal and civil defamation have been very closely linked. The elements and defences are substantially alike. There were several calls prior to 1994 for the abrogation of criminal defamation. Now that the right to an unimpaired reputation, as part of the right to human dignity, and the right to freedom of expression is constitutionally guaranteed, quo vadis the crime of criminal defamation? The Supreme Court of Appeal has recently granted a petition for leave to appeal against convictions for criminal defamation on this very point: is the offence constitutional. Due to the paucity of criminal defamation precedent, the copious civil law precedent concerning civil defamation must be analysed to determine what view the Supreme Court of Appeal will adopt. Prior to 1994 the right to an unimpaired reputation has trumped freedom of expression. Since then, the two leading decisions by the Supreme Court of Appeal and the Constitutional Court have ameliorated this situation slightly, according freedom of expression more weight. Claiming the previous common law position was incorrect, they claim the present common law position is constitutionally sound. Thus the Constitution has in essence had no effect to date upon the balancing of competing rights in the law of defamation. Both courts have erred in according the right to freedom of expression too little weight. This may be due to three judicial errors. Firstly, they have under-appreciated that the values of dignity, equality and freedom fortify and are fortified by the right to freedom of expression. Aspects of dignity such as self-actualisation, self-governance and an acceptance that humans have intrinsic worth are heavily reliant on freedom of expression, particularly political expression. Secondly, while political expression lies at the core of freedom of expression, reputation lies nearer the periphery of the right to dignity. Rights at the core ought to trump competing but peripheral rights. Thirdly, erroneous statements are inevitable in free debate. Unless they too are protected, unacceptable self-censorship occurs. The correct approach is as a matter of policy, particularly regarding political expression, to balance the competing rights with one’s thumb on the free expression side of the scales. This seems the trend of the European Court of Human Rights in recent cases In Canada, an offence punishing libel made intentionally but without knowledge of its falsity was recently ruled unconstitutional. On the other hand, another offence punishing libel made with knowledge it was false, videlicet punishing the intentional publication of defamatory lies, was ruled constitutional. Criminal defamation clearly infringes upon the right to freedom of expression. For this infringement to pass constitutional muster it must be reasonable and justifiable in an open and democratic society. It fails the limitation test due to the lack of proportionality between its objective in protecting the right to an unimpaired reputation and the harm it does to the right to expression. There are three reasons: firstly the “chilling effect” of imprisonment, over and above pecuniary damages, unacceptably stifles free debate. Secondly, it may punish even the truth, yet protect a falsehood, since the truth per se is not a defence. An undeserved reputation is thus more highly valued than the publication of that truth. Finally there is a well-developed civil remedy that adequately protects the right to reputation of aggrieved persons. In the appeal concerning the constitutionality of the common law offence of criminal defamation, the Supreme Court of Appeal ought to find it unconstitutional.
- Full Text:
- Date Issued: 2008
Factors influencing interracial mixing amongst university students
- Authors: Flusk, Lynette Michelle
- Date: 2008
- Subjects: Spatial behavior , Social distance , Students -- South Africa -- Attitudes , Prejudice (Psychology) , College integration -- South Africa , Colleges and universities -- South Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11849 , http://hdl.handle.net/10353/150 , Spatial behavior , Social distance , Students -- South Africa -- Attitudes , Prejudice (Psychology) , College integration -- South Africa , Colleges and universities -- South Africa -- Social conditions
- Description: This study examines the reasons given for the lack of interracial contact among 188 (142 Black, 25 White and 19 Coloured) university students. The most pervasive factor influencing such contact for the whole group (79.1 percent) was language differences. The statements endorsed by most black participants were; differences in behaviour (62.9 percent), socio-economic status (56.0 percent) and culture (52.5 percent). The coloured participants endorsed statements concerning socio-economic status (61.1 percent), culture (42.1 percent) and dissociation (42.1 percent). The white participants endorsed statements regarding race issues (64.0 percent), differences in behaviour (60.0 percent) and cultural differences (44.0 percent). This study found that metastereotypes social distance and contact correlate with prejudice. Metastereotypes and social distance positively influence prejudice in that an increase in these factors is associated with heightened levels of prejudice. The amount of contact between groups has a negative relationship with prejudice, indicating that increased levels of contact are associated with a decrease in prejudice.
- Full Text:
- Date Issued: 2008
- Authors: Flusk, Lynette Michelle
- Date: 2008
- Subjects: Spatial behavior , Social distance , Students -- South Africa -- Attitudes , Prejudice (Psychology) , College integration -- South Africa , Colleges and universities -- South Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , M Soc Sc (C Psy)
- Identifier: vital:11849 , http://hdl.handle.net/10353/150 , Spatial behavior , Social distance , Students -- South Africa -- Attitudes , Prejudice (Psychology) , College integration -- South Africa , Colleges and universities -- South Africa -- Social conditions
- Description: This study examines the reasons given for the lack of interracial contact among 188 (142 Black, 25 White and 19 Coloured) university students. The most pervasive factor influencing such contact for the whole group (79.1 percent) was language differences. The statements endorsed by most black participants were; differences in behaviour (62.9 percent), socio-economic status (56.0 percent) and culture (52.5 percent). The coloured participants endorsed statements concerning socio-economic status (61.1 percent), culture (42.1 percent) and dissociation (42.1 percent). The white participants endorsed statements regarding race issues (64.0 percent), differences in behaviour (60.0 percent) and cultural differences (44.0 percent). This study found that metastereotypes social distance and contact correlate with prejudice. Metastereotypes and social distance positively influence prejudice in that an increase in these factors is associated with heightened levels of prejudice. The amount of contact between groups has a negative relationship with prejudice, indicating that increased levels of contact are associated with a decrease in prejudice.
- Full Text:
- Date Issued: 2008
An investigation into the time-saving benefits of using a computerised taxation program
- Forster, Rory, Stack, Elizabeth M
- Authors: Forster, Rory , Stack, Elizabeth M
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: Conference paper
- Identifier: vital:6065 , http://hdl.handle.net/10962/d1004610
- Description: Software programs designed to calculate the tax liability of individuals and other types of tax entity are being designed and used with increasing frequency. Research done in the United States of America appears to indicate that these programs do not achieve any saving in time and, in fact, may take longer to use than to complete a tax return by hand. As the South African revenue collection system appears to be moving closer to a self-assessment system, where the calculation of tax owing will be the responsibility of the taxpayer, the research essay sets out to determine whether there is a saving in time when calculating a tax liability using a tax software program, instead of calculating it by hand. In addition, the research aims to determine how much time, on average, is saved or lost, using such a program, and whether there is any correlation between the time taken to perform a calculation by hand and that using the software program. It does so by comparing the average estimated time it would take to complete tax calculations for individuals by hand with the average time taken to complete the same tax calculations using a tax software program. The average time taken to do the calculations by hand is based on the time allocation given for questions by the authors of a published question bank for university students. The time taken using software is determined by using a stop-watch to time each question being processed. The results, subject to assumptions made in carrying out the research, show that there is a substantial saving in time using the software program. Based on the data, however, the results indicate a weak correlation between the estimated time taken to do a calculation by hand and the estimated time using the software program. Possible reasons for the weak correlation are discussed. A recommendation is also made for the standardization and certification of existing tax calculation software.
- Full Text:
- Date Issued: 2008
- Authors: Forster, Rory , Stack, Elizabeth M
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: Conference paper
- Identifier: vital:6065 , http://hdl.handle.net/10962/d1004610
- Description: Software programs designed to calculate the tax liability of individuals and other types of tax entity are being designed and used with increasing frequency. Research done in the United States of America appears to indicate that these programs do not achieve any saving in time and, in fact, may take longer to use than to complete a tax return by hand. As the South African revenue collection system appears to be moving closer to a self-assessment system, where the calculation of tax owing will be the responsibility of the taxpayer, the research essay sets out to determine whether there is a saving in time when calculating a tax liability using a tax software program, instead of calculating it by hand. In addition, the research aims to determine how much time, on average, is saved or lost, using such a program, and whether there is any correlation between the time taken to perform a calculation by hand and that using the software program. It does so by comparing the average estimated time it would take to complete tax calculations for individuals by hand with the average time taken to complete the same tax calculations using a tax software program. The average time taken to do the calculations by hand is based on the time allocation given for questions by the authors of a published question bank for university students. The time taken using software is determined by using a stop-watch to time each question being processed. The results, subject to assumptions made in carrying out the research, show that there is a substantial saving in time using the software program. Based on the data, however, the results indicate a weak correlation between the estimated time taken to do a calculation by hand and the estimated time using the software program. Possible reasons for the weak correlation are discussed. A recommendation is also made for the standardization and certification of existing tax calculation software.
- Full Text:
- Date Issued: 2008
A comparison between the South African "source rules" in relation to income tax and the "permanent establishment rules" as contained in double taxation agreements
- Authors: Fourie, Leonie
- Date: 2008
- Subjects: Income tax -- South Africa , Income tax -- Law and legislation -- South Africa , Double taxation -- South Africa , Business enterprises -- Taxation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:905 , http://hdl.handle.net/10962/d1008203
- Description: South Africa's right to tax the income of a non-resident is determined in terms of the South African "source rules" established by court decisions in relation to the imposition of tax in terms of the Income Tax Act. Unless a non-resident's income is captured by the South African "source rules" (on the basis that hi slits income is derived from a South African source), South Africa would have no right to tax such income, even if such non-resident creates a permanent establishment in South Africa by performing business activities within South Africa which could be considered essential (but not dominant) in nature. In such scenario the activities performed by the non-resident in South Africa may utilise the natural resources and the infrastructure of South Africa, but the South African fiscus would be deprived of the right to any tax revenues attributable to the income produced partly by such activities within South Africa. The South African "source rules" refer only to the main or dominant activities giving rise to the income for the purpose of determining the source of such income (and accordingly the right to tax such income). On the other hand, the "permanent establishment rules" as set out under the Organisation for Economic Cooperation and Development Model Tax Convention on Income and on Capital refer to all the taxpayer's essential business activities for the purpose of determining whether or not such activities create a pennanent establishment. The result of the narrow nature of the South African "source rules" is that, under certain circumstances, the South African fiscus would not necessarily be granted the right to tax all income produced partly within South Africa. The research demonstrated that incorporating the principles underlying the "pennanent establishment rules" into South African legislation would be a reasonable and logical solution to the problem of detennining the source of income. In so doing, the South African "source rules" would determine the source of income, and consequently South Africa's taxing rights, with reference to the essential business activities giving rise to such income. In such case South Africa would be afforded the right to tax the income of a non-resident in the event that it performs any of its essential business activities within South Africa, albeit not the dominant or main activities giving rise to the income.
- Full Text:
- Date Issued: 2008
- Authors: Fourie, Leonie
- Date: 2008
- Subjects: Income tax -- South Africa , Income tax -- Law and legislation -- South Africa , Double taxation -- South Africa , Business enterprises -- Taxation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:905 , http://hdl.handle.net/10962/d1008203
- Description: South Africa's right to tax the income of a non-resident is determined in terms of the South African "source rules" established by court decisions in relation to the imposition of tax in terms of the Income Tax Act. Unless a non-resident's income is captured by the South African "source rules" (on the basis that hi slits income is derived from a South African source), South Africa would have no right to tax such income, even if such non-resident creates a permanent establishment in South Africa by performing business activities within South Africa which could be considered essential (but not dominant) in nature. In such scenario the activities performed by the non-resident in South Africa may utilise the natural resources and the infrastructure of South Africa, but the South African fiscus would be deprived of the right to any tax revenues attributable to the income produced partly by such activities within South Africa. The South African "source rules" refer only to the main or dominant activities giving rise to the income for the purpose of determining the source of such income (and accordingly the right to tax such income). On the other hand, the "permanent establishment rules" as set out under the Organisation for Economic Cooperation and Development Model Tax Convention on Income and on Capital refer to all the taxpayer's essential business activities for the purpose of determining whether or not such activities create a pennanent establishment. The result of the narrow nature of the South African "source rules" is that, under certain circumstances, the South African fiscus would not necessarily be granted the right to tax all income produced partly within South Africa. The research demonstrated that incorporating the principles underlying the "pennanent establishment rules" into South African legislation would be a reasonable and logical solution to the problem of detennining the source of income. In so doing, the South African "source rules" would determine the source of income, and consequently South Africa's taxing rights, with reference to the essential business activities giving rise to such income. In such case South Africa would be afforded the right to tax the income of a non-resident in the event that it performs any of its essential business activities within South Africa, albeit not the dominant or main activities giving rise to the income.
- Full Text:
- Date Issued: 2008
Improving academic literacy at higher education
- Authors: Free, Loretta Dianna
- Date: 2008
- Subjects: Literacy -- Study and teaching (Higher) , Information literacy -- Study and teaching (Higher) , Academic writing -- Study and teaching (Higher)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9531 , http://hdl.handle.net/10948/839 , Literacy -- Study and teaching (Higher) , Information literacy -- Study and teaching (Higher) , Academic writing -- Study and teaching (Higher)
- Description: This study is a deliberation on students who advance from high school to a higher education institution, without demonstrating the attributes required on admission. They are granted formal access, despite being underprepared for tertiary studies. One of the qualities that they noticible lack is academic literacy. In the course of this investigation, academics had to relate what their perceptions were of the academic literacy of their students at higher education level. Initially, being literate meant the ability to read and write, but the term literacy has assumed a more varied form. The term multi-literacies is employed now, as there are several forms of literacy. These include, Information Technology, Technology, pictorial and numerical literacies, to name a few. Academic literacy constitutes more than one literacy, namely, operational or functional literacy, cultural literacy and critical literacy. These literacies are elaborated on and the role of language proficiency, together with the inter-relatedness between students' linguistic competence and their cognitive ability are discussed in depth. Alternatives are examined to assess how this problem of the lack of academic literacy can be circumvented and what mechanisms can be put in place in order that students can be assisted in their pursuit of academic literacy.
- Full Text:
- Date Issued: 2008
- Authors: Free, Loretta Dianna
- Date: 2008
- Subjects: Literacy -- Study and teaching (Higher) , Information literacy -- Study and teaching (Higher) , Academic writing -- Study and teaching (Higher)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9531 , http://hdl.handle.net/10948/839 , Literacy -- Study and teaching (Higher) , Information literacy -- Study and teaching (Higher) , Academic writing -- Study and teaching (Higher)
- Description: This study is a deliberation on students who advance from high school to a higher education institution, without demonstrating the attributes required on admission. They are granted formal access, despite being underprepared for tertiary studies. One of the qualities that they noticible lack is academic literacy. In the course of this investigation, academics had to relate what their perceptions were of the academic literacy of their students at higher education level. Initially, being literate meant the ability to read and write, but the term literacy has assumed a more varied form. The term multi-literacies is employed now, as there are several forms of literacy. These include, Information Technology, Technology, pictorial and numerical literacies, to name a few. Academic literacy constitutes more than one literacy, namely, operational or functional literacy, cultural literacy and critical literacy. These literacies are elaborated on and the role of language proficiency, together with the inter-relatedness between students' linguistic competence and their cognitive ability are discussed in depth. Alternatives are examined to assess how this problem of the lack of academic literacy can be circumvented and what mechanisms can be put in place in order that students can be assisted in their pursuit of academic literacy.
- Full Text:
- Date Issued: 2008
The devil in disguise a comparative study of Thomas Mann's "Doktor Faustus" (1947) and Klaus Mann's "Mephisto" (1936), focussing on the role of art as an allegory of the rise and fall of Nazi Germany
- Authors: French, Rebecca S C
- Date: 2008
- Subjects: Mann, Thomas, 1875-1955 Doktor Faustus Mann, Klaus, 1906-1949 Mephisto Arts, German -- 20th Century Art, Germany -- 20th Century National socialism in art National socialism in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3582 , http://hdl.handle.net/10962/d1002157
- Description: This thesis compares the novels Doktor Faustus: das Leben des deutschen Tonsetzers Adrian Leverkühn, erzählt von einem Freunde (Thomas Mann) and Mephisto: Roman einer Karriere (Klaus Mann), insofar as they are portrayals of the situation in Germany during the Third Reich. Essentially a comparative study, I explore similarities and differences – thematic and conceptual – by situating both novels in their socio-historical moment (Chapter 1), exploring their conceptions of German national identity (Chapter 2), tracing intertextual connections to other works (Chapter 3), and, finally, examining their understanding of and reliance on art as insofar as it provides the allegorical framework for their respective portrayals of Nazi Germany (Chapter 4).
- Full Text:
- Date Issued: 2008
- Authors: French, Rebecca S C
- Date: 2008
- Subjects: Mann, Thomas, 1875-1955 Doktor Faustus Mann, Klaus, 1906-1949 Mephisto Arts, German -- 20th Century Art, Germany -- 20th Century National socialism in art National socialism in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3582 , http://hdl.handle.net/10962/d1002157
- Description: This thesis compares the novels Doktor Faustus: das Leben des deutschen Tonsetzers Adrian Leverkühn, erzählt von einem Freunde (Thomas Mann) and Mephisto: Roman einer Karriere (Klaus Mann), insofar as they are portrayals of the situation in Germany during the Third Reich. Essentially a comparative study, I explore similarities and differences – thematic and conceptual – by situating both novels in their socio-historical moment (Chapter 1), exploring their conceptions of German national identity (Chapter 2), tracing intertextual connections to other works (Chapter 3), and, finally, examining their understanding of and reliance on art as insofar as it provides the allegorical framework for their respective portrayals of Nazi Germany (Chapter 4).
- Full Text:
- Date Issued: 2008
Drought responses of C3 and C4 (NADP-ME) Panicoid grasses
- Authors: Frole, Kristen Marie
- Date: 2008
- Subjects: Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4193 , http://hdl.handle.net/10962/d1003762 , Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Description: The success of C₄ plants lies in their ability to concentrate CO₂ at the site of Rubisco thereby conferring greater efficiencies of light, water and nitrogen. Such characteristics should advantage C₄ plants in arid, hot environments. However, not all C₄ subtypes are drought tolerant. The relative abundance of NADP-ME species declines with increasing aridity. Furthermore, selected species have been demonstrated as being susceptible to severe drought showing metabolic limitations of photosynthesis. However there is a lack of phylogenetic control with many of these studies. The aims of this study were to determine whether the NADP-ME subtype was inherently susceptible to drought by comparing six closely related C₃ and C₄ (NADP-ME) Panicoid grasses. Gas exchange measurements were made during a natural rainless period and a controlled drought / rewatering event. Prior to water stress, the C₄ species had higher assimilation rates (A), and water use efficiencies (WUE[subscript leaf]) than the C₃ species, while transpiration rates (E) and stomatal conductances (g[subscript s]) were similar. At low soil water content, the C₃ species reduced gs by a greater extent than the C₄ species, which maintained higher E during the driest periods. The C₄ species showed proportionally greater reductions in A than the C₃ species and hence lost their WUE[subscript leaf] and photosynthetic advantage. CO₂ response curves showed that metabolic limitation was responsible for a greater decrease in A in the C₄ type than the C₃ type during progressive drought. Upon re-watering, photosynthetic recovery was quicker in the C species than the C₄ species. Results from whole plant measurements showed that the C₄ type had a significant whole plant water use efficiency advantage over the C₃ type under well-watered conditions that was lost during severe drought due to a greater loss of leaf area through leaf mortality rather than reductions in plant level transpiration rates. The C₃ type had xylem characteristics that enhanced water-conducting efficiency, but made them vulnerable to drought. This is in contrast to the safer xylem qualities of the C₄ type, which permitted the endurance of more negative leaf water potentials than the C₃ type during low soil water content. Thus, the vulnerability of photosynthesis to severe drought in NADP-ME species potentially explains why NADP-ME species abundance around the world decreases with decreasing rainfall.
- Full Text:
- Date Issued: 2008
- Authors: Frole, Kristen Marie
- Date: 2008
- Subjects: Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4193 , http://hdl.handle.net/10962/d1003762 , Botany -- Research , Grasses -- Physiology -- South Africa , Grasses -- Effect of drought on , Grasses -- Drought tolerance , Plant-water relationships
- Description: The success of C₄ plants lies in their ability to concentrate CO₂ at the site of Rubisco thereby conferring greater efficiencies of light, water and nitrogen. Such characteristics should advantage C₄ plants in arid, hot environments. However, not all C₄ subtypes are drought tolerant. The relative abundance of NADP-ME species declines with increasing aridity. Furthermore, selected species have been demonstrated as being susceptible to severe drought showing metabolic limitations of photosynthesis. However there is a lack of phylogenetic control with many of these studies. The aims of this study were to determine whether the NADP-ME subtype was inherently susceptible to drought by comparing six closely related C₃ and C₄ (NADP-ME) Panicoid grasses. Gas exchange measurements were made during a natural rainless period and a controlled drought / rewatering event. Prior to water stress, the C₄ species had higher assimilation rates (A), and water use efficiencies (WUE[subscript leaf]) than the C₃ species, while transpiration rates (E) and stomatal conductances (g[subscript s]) were similar. At low soil water content, the C₃ species reduced gs by a greater extent than the C₄ species, which maintained higher E during the driest periods. The C₄ species showed proportionally greater reductions in A than the C₃ species and hence lost their WUE[subscript leaf] and photosynthetic advantage. CO₂ response curves showed that metabolic limitation was responsible for a greater decrease in A in the C₄ type than the C₃ type during progressive drought. Upon re-watering, photosynthetic recovery was quicker in the C species than the C₄ species. Results from whole plant measurements showed that the C₄ type had a significant whole plant water use efficiency advantage over the C₃ type under well-watered conditions that was lost during severe drought due to a greater loss of leaf area through leaf mortality rather than reductions in plant level transpiration rates. The C₃ type had xylem characteristics that enhanced water-conducting efficiency, but made them vulnerable to drought. This is in contrast to the safer xylem qualities of the C₄ type, which permitted the endurance of more negative leaf water potentials than the C₃ type during low soil water content. Thus, the vulnerability of photosynthesis to severe drought in NADP-ME species potentially explains why NADP-ME species abundance around the world decreases with decreasing rainfall.
- Full Text:
- Date Issued: 2008
Decentralisation and development: the contradictions of local government in Uganda with specific reference to Masindi and Sembabule districts
- Authors: Galiwango, Wasswa Hassan
- Date: 2008
- Subjects: Decentralization in government -- Uganda , Local government -- Uganda , Uganda -- Politics and government
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8238 , http://hdl.handle.net/10948/780 , Decentralization in government -- Uganda , Local government -- Uganda , Uganda -- Politics and government
- Description: Decentralisation is the process through which Central Government transfers authority and functions to sub-national units of the Government and it traces its origin in Uganda from the “ bush” period (1981 – 1986) when Resistance Committees were established by the NRM/A in the Luwero triangle. The Mamdani Commission Report of 1987 on the Local Government system in Uganda recommended devolution of powers. Subsequently, decentralisation was launched in 1992, constitutionalised by the 1995 Constitution, and operationalised by the Local Governments Act (LGA) in 1997. Among the services devolved were education and health, which this study used as case studies to illustrate whether decentralisation has enhanced development in Uganda during the period 1993 – 2006. The study used both primary and secondary data in analysing the linkage between decentralisation and development in the two selected districts in Uganda, namely Masindi and Sembabule. Primary data was collected through interviews, questionnaires and focus group discussions while secondary data was gathered through a literature survey of relevant textbooks, newspapers, reports, legislation and journals. The findings of the study established that if decentralisation is properly planned and implemented it can make a meaningful contribution to enhancing development. However, since decentralisation is a process and not a once-off project, it evolves from one stage to another and, as it does so, it also unfolds new challenges and contradictions that need to be effectively addressed. These challenges include aspects relating to the legal framework, as well as political, fiscal and administrative decentralisation. The study recommended mitigation measures to enhance the efficiency, effectiveness, accountability, transparency, and subsequently the quality of services delivered (development) under decentralised local governance in Uganda.
- Full Text:
- Date Issued: 2008
- Authors: Galiwango, Wasswa Hassan
- Date: 2008
- Subjects: Decentralization in government -- Uganda , Local government -- Uganda , Uganda -- Politics and government
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:8238 , http://hdl.handle.net/10948/780 , Decentralization in government -- Uganda , Local government -- Uganda , Uganda -- Politics and government
- Description: Decentralisation is the process through which Central Government transfers authority and functions to sub-national units of the Government and it traces its origin in Uganda from the “ bush” period (1981 – 1986) when Resistance Committees were established by the NRM/A in the Luwero triangle. The Mamdani Commission Report of 1987 on the Local Government system in Uganda recommended devolution of powers. Subsequently, decentralisation was launched in 1992, constitutionalised by the 1995 Constitution, and operationalised by the Local Governments Act (LGA) in 1997. Among the services devolved were education and health, which this study used as case studies to illustrate whether decentralisation has enhanced development in Uganda during the period 1993 – 2006. The study used both primary and secondary data in analysing the linkage between decentralisation and development in the two selected districts in Uganda, namely Masindi and Sembabule. Primary data was collected through interviews, questionnaires and focus group discussions while secondary data was gathered through a literature survey of relevant textbooks, newspapers, reports, legislation and journals. The findings of the study established that if decentralisation is properly planned and implemented it can make a meaningful contribution to enhancing development. However, since decentralisation is a process and not a once-off project, it evolves from one stage to another and, as it does so, it also unfolds new challenges and contradictions that need to be effectively addressed. These challenges include aspects relating to the legal framework, as well as political, fiscal and administrative decentralisation. The study recommended mitigation measures to enhance the efficiency, effectiveness, accountability, transparency, and subsequently the quality of services delivered (development) under decentralised local governance in Uganda.
- Full Text:
- Date Issued: 2008
Phytoplankton chlorophyll a concentration and community structure in two temporarily open/closed estuaries in the Eastern Cape, South Africa
- Authors: Gama, Phumelele Thuthuka
- Date: 2008
- Subjects: Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10621 , http://hdl.handle.net/10948/707 , Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Description: River flow is important in controlling phytoplankton distribution in estuaries. Data on the effect of river inflow on phytoplankton distribution patterns in temporarily open/closed estuaries is lacking. This study investigated the influence of river inflow on size-fractionated phytoplankton biomass (Chl a), community composition and environmental parameters measured monthly over three years in two temporarily open/closed estuaries in the Eastern Cape, South Africa. A once-off primary production study over an annual cycle was completed in the Van Stadens and Maitland estuaries. The study monitored physical, chemical and biological characteristics in both estuaries to examine the effects of changes in environmental factors and river inflow. Daily sampling of physico-chemical and biological variables from river to sea was carried out in the Van Stadens to investigate short-time scale effects of changes in environmental factors and river inflow on the phytoplankton biomass. Five and three stations in the main channel of the Van Stadens and Maitland estuaries respectively were sampled at 0.5 m below the water surface and 0.5 m above the sediment surface for biological and chemical variables and at the surface, 0.25 m and every 0.5 m thereafter for physical parameters. Five stations adjacent to the main channel along the estuary were monitored for groundwater macronutrient concentrations and five additional sites located within the upper catchment of the Van Stadens River were sampled on a quarterly basis over two years. Both estuaries were characterised by distinct hydrological conditions, an overwash, an open, a closed and a semi-closed mouth phase. Flooding in the Maitland and Van Stadens estuaries in 2001 and 2002 caused sediment scour, altered channel morphology and brought about breaching of the mouth. Flood driven mouth-breaching events occurred three and four times in each of the estuaries during the study. The mouth stayed open 20 – 25 percent and was closed 60 – 65 percent of the time. In the Van Stadens the closed overwash mouth condition occurred approximately 10 – 20 percent of the time while in the Maitland it occurred less with the semi-closed mouth condition occurring 10 – 20 percent of the time. Incidents related to mouth opening not associated with strong river floods occurred approximately 10 – 15 percent of the time, although in the Maitland a semi-closed mouth state persisted more frequently than in the Van Stadens Estuary. During flooding events salinity dropped to low levels (< 5 psu) but soon recovered to brackish conditions when river flow was reduced and marine water penetrated deep upstream. Reduction in river flow combined with marine sediment deposition resulted in the closure of the mouth. During closed mouth conditions strong onshore storm surges and spring high tides introduced marine water through overwash that kept salinity high. In both estuaries salinity showed a negative correlation with rainfall (R2 = 0.12), indicative of the strong influence of marine overwash that kept salinity high thus masking the influence of freshwater. High rainfall in the Van Stadens Estuary caused high levels of turbidity that reduced light penetration at depth. Light attenuation was positively correlated with the high rainfall (R 2 = 0.26) suggesting that increased turbidity was linked to rainfall induced discharge. In contrast, in the Maitland Estuary light attenuation did not show any correlation with increased rainfall possibly because of the reduced water depth and increased euphotic zone following the floods in 2002. High river inflow introduced macronutrients in both estuaries such that dissolved inorganic phosphates (DIP) and dissolved inorganic nitrogen (DIN) concentrations in the Van Stadens Estuary were strongly correlated with rainfall (R2 = 0.78 and 0.57 respectively). In the Maitland Estuary DIP and DIN concentrations remained significantly higher (p < 0.05) compared to that in the Van Stadens suggesting that the Maitland catchment contributed greater nutrient input into the estuary and may be associated with farming activities. Phytoplankton chlorophyll a (Chl a) ranged from 0.8 – 13.9 μg L-1 in the Van Stadens and in the Maitland Estuary from 5.3 – 138 μg L-1 during the 3-year study. During the open mouth condition Chl a biomass and primary production ranged from 5.4 – 52.9 μg Chl a L-1 and 1.2 – 11.7 mg C m-2 d-1 in the Maitland and in the Van Stadens from 1.6 – 9.8 μg Chl a L-1 and 1.2 - 14 mg C m-2 d-1 respectively. Maximum annual primary production in the Maitland and Van Stadens estuaries was 8.8 and 5.1 g C m-2 y-1 respectively. When the mouth was open in the Van Stadens Estuary the microphytoplankton (> 20 μm) accounted for > 65 percent of the Chl a, whereas during closed mouth conditions they accounted for about 55 percent of the Chl a biomass. Chlorophytes became the dominant taxon in the dry summer months but were replaced by cryptophytes and dinoflagellates during the wet season. When nutrient concentrations were low during low flow conditions in the Van Stadens Estuary mixotrophic microphytoplankton became an important fraction of the water column together with phototrophic dinoflagellates and cryptophytes. In the Maitland large sized chlorophytes were the dominant taxa in late spring and summer seasons and made up more than 80 percent of the cell numbers. In the Maitland before the floods in 2002 cyanophytes were the dominant group in late spring contributing more than 75 percent in cell abundance. Data from the short-term study in the Van Stadens Estuary showed similarities and differences in the Chl a response to increased river inflow. High river inflow initially reduced Chl a biomass followed by a recovery period of a couple of days compared to a 8 – 10 week recovery period in studies monitored over seasonal and annual temporal scales. The responses may be dissimilar but help to illustrate that there are similar response patterns to environmental forcing necessary to support phytoplankton biomass at different temporal scales. This study has demonstrated that flooding events caused by strong river flow cause breaching of the mouth, a reduction in salinity and marked nutrient input. Although the causes of flooding can be similar in both estuaries the resultant effects are varied and can alter the ability of the estuary to retain water. This study was able to demonstrate that the supply of macronutrients from the catchment was strongly correlated with rainfall (R2 = 0.67) and that phytoplankton growth mainly depended on an allochthonous source of macronutrients although internal supplies could be critical at times in controlling microalgal biomass.
- Full Text:
- Date Issued: 2008
- Authors: Gama, Phumelele Thuthuka
- Date: 2008
- Subjects: Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10621 , http://hdl.handle.net/10948/707 , Estuarine ecology -- South Africa , Chlorophyll -- South Africa , Estuaries -- South Africa , Phytoplankton populations -- South Africa
- Description: River flow is important in controlling phytoplankton distribution in estuaries. Data on the effect of river inflow on phytoplankton distribution patterns in temporarily open/closed estuaries is lacking. This study investigated the influence of river inflow on size-fractionated phytoplankton biomass (Chl a), community composition and environmental parameters measured monthly over three years in two temporarily open/closed estuaries in the Eastern Cape, South Africa. A once-off primary production study over an annual cycle was completed in the Van Stadens and Maitland estuaries. The study monitored physical, chemical and biological characteristics in both estuaries to examine the effects of changes in environmental factors and river inflow. Daily sampling of physico-chemical and biological variables from river to sea was carried out in the Van Stadens to investigate short-time scale effects of changes in environmental factors and river inflow on the phytoplankton biomass. Five and three stations in the main channel of the Van Stadens and Maitland estuaries respectively were sampled at 0.5 m below the water surface and 0.5 m above the sediment surface for biological and chemical variables and at the surface, 0.25 m and every 0.5 m thereafter for physical parameters. Five stations adjacent to the main channel along the estuary were monitored for groundwater macronutrient concentrations and five additional sites located within the upper catchment of the Van Stadens River were sampled on a quarterly basis over two years. Both estuaries were characterised by distinct hydrological conditions, an overwash, an open, a closed and a semi-closed mouth phase. Flooding in the Maitland and Van Stadens estuaries in 2001 and 2002 caused sediment scour, altered channel morphology and brought about breaching of the mouth. Flood driven mouth-breaching events occurred three and four times in each of the estuaries during the study. The mouth stayed open 20 – 25 percent and was closed 60 – 65 percent of the time. In the Van Stadens the closed overwash mouth condition occurred approximately 10 – 20 percent of the time while in the Maitland it occurred less with the semi-closed mouth condition occurring 10 – 20 percent of the time. Incidents related to mouth opening not associated with strong river floods occurred approximately 10 – 15 percent of the time, although in the Maitland a semi-closed mouth state persisted more frequently than in the Van Stadens Estuary. During flooding events salinity dropped to low levels (< 5 psu) but soon recovered to brackish conditions when river flow was reduced and marine water penetrated deep upstream. Reduction in river flow combined with marine sediment deposition resulted in the closure of the mouth. During closed mouth conditions strong onshore storm surges and spring high tides introduced marine water through overwash that kept salinity high. In both estuaries salinity showed a negative correlation with rainfall (R2 = 0.12), indicative of the strong influence of marine overwash that kept salinity high thus masking the influence of freshwater. High rainfall in the Van Stadens Estuary caused high levels of turbidity that reduced light penetration at depth. Light attenuation was positively correlated with the high rainfall (R 2 = 0.26) suggesting that increased turbidity was linked to rainfall induced discharge. In contrast, in the Maitland Estuary light attenuation did not show any correlation with increased rainfall possibly because of the reduced water depth and increased euphotic zone following the floods in 2002. High river inflow introduced macronutrients in both estuaries such that dissolved inorganic phosphates (DIP) and dissolved inorganic nitrogen (DIN) concentrations in the Van Stadens Estuary were strongly correlated with rainfall (R2 = 0.78 and 0.57 respectively). In the Maitland Estuary DIP and DIN concentrations remained significantly higher (p < 0.05) compared to that in the Van Stadens suggesting that the Maitland catchment contributed greater nutrient input into the estuary and may be associated with farming activities. Phytoplankton chlorophyll a (Chl a) ranged from 0.8 – 13.9 μg L-1 in the Van Stadens and in the Maitland Estuary from 5.3 – 138 μg L-1 during the 3-year study. During the open mouth condition Chl a biomass and primary production ranged from 5.4 – 52.9 μg Chl a L-1 and 1.2 – 11.7 mg C m-2 d-1 in the Maitland and in the Van Stadens from 1.6 – 9.8 μg Chl a L-1 and 1.2 - 14 mg C m-2 d-1 respectively. Maximum annual primary production in the Maitland and Van Stadens estuaries was 8.8 and 5.1 g C m-2 y-1 respectively. When the mouth was open in the Van Stadens Estuary the microphytoplankton (> 20 μm) accounted for > 65 percent of the Chl a, whereas during closed mouth conditions they accounted for about 55 percent of the Chl a biomass. Chlorophytes became the dominant taxon in the dry summer months but were replaced by cryptophytes and dinoflagellates during the wet season. When nutrient concentrations were low during low flow conditions in the Van Stadens Estuary mixotrophic microphytoplankton became an important fraction of the water column together with phototrophic dinoflagellates and cryptophytes. In the Maitland large sized chlorophytes were the dominant taxa in late spring and summer seasons and made up more than 80 percent of the cell numbers. In the Maitland before the floods in 2002 cyanophytes were the dominant group in late spring contributing more than 75 percent in cell abundance. Data from the short-term study in the Van Stadens Estuary showed similarities and differences in the Chl a response to increased river inflow. High river inflow initially reduced Chl a biomass followed by a recovery period of a couple of days compared to a 8 – 10 week recovery period in studies monitored over seasonal and annual temporal scales. The responses may be dissimilar but help to illustrate that there are similar response patterns to environmental forcing necessary to support phytoplankton biomass at different temporal scales. This study has demonstrated that flooding events caused by strong river flow cause breaching of the mouth, a reduction in salinity and marked nutrient input. Although the causes of flooding can be similar in both estuaries the resultant effects are varied and can alter the ability of the estuary to retain water. This study was able to demonstrate that the supply of macronutrients from the catchment was strongly correlated with rainfall (R2 = 0.67) and that phytoplankton growth mainly depended on an allochthonous source of macronutrients although internal supplies could be critical at times in controlling microalgal biomass.
- Full Text:
- Date Issued: 2008
Investigation of polarization mode dispersion measurement perfomance in optical fibre with a focus on the fixed analyzer technique
- Gamatham, Romeo Reginald Gunther
- Authors: Gamatham, Romeo Reginald Gunther
- Date: 2008
- Subjects: Fiber optics , Polarization (Light)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10524 , http://hdl.handle.net/10948/957 , Fiber optics , Polarization (Light)
- Description: The work presented in this dissertation is a comparative study of polarization mode dispersion (PMD) measurement performance where the fixed analyzer (FA) technique was built and tested for the first time in South Africa. Techniques involved in the study are: the Jones matrix eigenanalysis (JME), generalised interferometric technique (GINTY) and the FA technique, with a particular focus on the FA technique. The FA PMD measurement technique determines the average differential group delay (DGD) from the transmitted intensity spectrum through a polarizer and has three analysis methods (extrema counting, mean level crossing and Fourier analysis) which were all evaluated. PMD measurements were performed in the laboratory on several different fibre types and in the field on buried deployed Telkom fibre links (28.8 km). The techniques showed good agreement in the measured PMD value, both in the laboratory and field measurements. In particular very good agreement was found between the JME average DGD and the extrema counting analysis PMD value. The GINTY and FA Fourier analysis method also gave very similar PMD values. It was found that the fibre birefringence and the mode coupling manifest in different ways on the intensity spectrum. By using the FA ratio method, the length regimes of the different fibre types were determined. Three characteristics of the FA technique were investigated, namely: wavelength window variation, sampling and input SOP scrambling. It was found that the wavelength window and the PMD are inversely proportional. Correct sampling plays a significant role in determining the correct measured PMD value. Lastly an average PMD value over the PMD values for different input SOPs serves as a better representation of the true PMD value. An additional study showed that the FA technique and a developed Poincaré sphere analysis method agree very well regarding the PMD value.
- Full Text:
- Date Issued: 2008
- Authors: Gamatham, Romeo Reginald Gunther
- Date: 2008
- Subjects: Fiber optics , Polarization (Light)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10524 , http://hdl.handle.net/10948/957 , Fiber optics , Polarization (Light)
- Description: The work presented in this dissertation is a comparative study of polarization mode dispersion (PMD) measurement performance where the fixed analyzer (FA) technique was built and tested for the first time in South Africa. Techniques involved in the study are: the Jones matrix eigenanalysis (JME), generalised interferometric technique (GINTY) and the FA technique, with a particular focus on the FA technique. The FA PMD measurement technique determines the average differential group delay (DGD) from the transmitted intensity spectrum through a polarizer and has three analysis methods (extrema counting, mean level crossing and Fourier analysis) which were all evaluated. PMD measurements were performed in the laboratory on several different fibre types and in the field on buried deployed Telkom fibre links (28.8 km). The techniques showed good agreement in the measured PMD value, both in the laboratory and field measurements. In particular very good agreement was found between the JME average DGD and the extrema counting analysis PMD value. The GINTY and FA Fourier analysis method also gave very similar PMD values. It was found that the fibre birefringence and the mode coupling manifest in different ways on the intensity spectrum. By using the FA ratio method, the length regimes of the different fibre types were determined. Three characteristics of the FA technique were investigated, namely: wavelength window variation, sampling and input SOP scrambling. It was found that the wavelength window and the PMD are inversely proportional. Correct sampling plays a significant role in determining the correct measured PMD value. Lastly an average PMD value over the PMD values for different input SOPs serves as a better representation of the true PMD value. An additional study showed that the FA technique and a developed Poincaré sphere analysis method agree very well regarding the PMD value.
- Full Text:
- Date Issued: 2008
A molecular analysis of the Afrotropical Baetidae
- Gattolliat, J L, Monaghan, M T, Sartori, Michel, Elouard, J M, Barber-James, Helen M, Derleth, P, Glaizot, Olivier, De Moor, Ferdy C, Vogler, Alfred P
- Authors: Gattolliat, J L , Monaghan, M T , Sartori, Michel , Elouard, J M , Barber-James, Helen M , Derleth, P , Glaizot, Olivier , De Moor, Ferdy C , Vogler, Alfred P
- Date: 2008
- Language: English
- Type: Text
- Identifier: vital:528 , http://hdl.handle.net/10962/d1008393
- Description: Recent work on the Afrotropical Baetidae has resulted in a number of important taxonomic changes: several polyphyletic genera have been split and more than 30 new Afrotropical genera have been established. In order to test their phylogenetic relevance and to clarify the suprageneric relationships, we reconstructed the first comprehensive molecular phylogeny of the Afrotropical Baetidae. We sequenced a total of ca. 2300 bp from nuclear (18S) and mitochondrial (12S and 16S) gene regions from 65 species belonging to 26 genera. We used three different approaches of phylogeny reconstruction: direct optimization, maximum parsimony and maximum likelihood. The molecular reconstruction indicates the Afrotropical Baetidae require a global revision at a generic as well as suprageneric level. Only four of the 12 genera were monophyletic when represented by more than one species in the analysis. Historically, two conflicting concepts of the suprageneric classification of Afrotropical Baetidae were proposed. One was based on the gathering of sister genera into complexes and the other on the division of the family into a restricted number of subfamilies. According to our reconstruction, neither is completely satisfactory: the major complexes of genera present in Africa are either paraphyletic or polyphyletic and the division of the Afrotropical Baetidae into two subfamilies is probably too simplified.
- Full Text:
- Date Issued: 2008
- Authors: Gattolliat, J L , Monaghan, M T , Sartori, Michel , Elouard, J M , Barber-James, Helen M , Derleth, P , Glaizot, Olivier , De Moor, Ferdy C , Vogler, Alfred P
- Date: 2008
- Language: English
- Type: Text
- Identifier: vital:528 , http://hdl.handle.net/10962/d1008393
- Description: Recent work on the Afrotropical Baetidae has resulted in a number of important taxonomic changes: several polyphyletic genera have been split and more than 30 new Afrotropical genera have been established. In order to test their phylogenetic relevance and to clarify the suprageneric relationships, we reconstructed the first comprehensive molecular phylogeny of the Afrotropical Baetidae. We sequenced a total of ca. 2300 bp from nuclear (18S) and mitochondrial (12S and 16S) gene regions from 65 species belonging to 26 genera. We used three different approaches of phylogeny reconstruction: direct optimization, maximum parsimony and maximum likelihood. The molecular reconstruction indicates the Afrotropical Baetidae require a global revision at a generic as well as suprageneric level. Only four of the 12 genera were monophyletic when represented by more than one species in the analysis. Historically, two conflicting concepts of the suprageneric classification of Afrotropical Baetidae were proposed. One was based on the gathering of sister genera into complexes and the other on the division of the family into a restricted number of subfamilies. According to our reconstruction, neither is completely satisfactory: the major complexes of genera present in Africa are either paraphyletic or polyphyletic and the division of the Afrotropical Baetidae into two subfamilies is probably too simplified.
- Full Text:
- Date Issued: 2008