An evaluation of recirculating artificial stream designs for acute toxicity testing using two South African Ephemeroptera species exposed to sodium sulphate
- Authors: Binder, Markus
- Date: 2000
- Subjects: Water -- Pollution -- Toxicology , Toxicology -- Research , Aquatic organisms -- Effect of water pollution on , Sodium sulfate , Mayflies
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5690 , http://hdl.handle.net/10962/d1005376 , Water -- Pollution -- Toxicology , Toxicology -- Research , Aquatic organisms -- Effect of water pollution on , Sodium sulfate , Mayflies
- Description: Three artificial stream designs, termed Large Artificial Stream Units (LASUs), Raceways, and Channels, at two major scales (1700 L, 12.5 L and 20 L recirculated volume) were developed at the Institute for Water Research, Rhodes University, Grahamstown, in order to explore the possibilities of using indigenous rheophilic macroinvertebrates in routine toxicity tests. This study compared these systems, using 96h-EC50 values from sodium sulphate toxicity tests as the experimental response. Two local Ephemeroptera (Leptophlebiidae: Adenophlebia auriculata Eaton, and Baetidae: Afroptilum sudafricanum Lestage) were evaluated for their suitability in routine toxicity tests; and the possible effects of elevated salinity levels in South African rivers on the test species were assessed. Two sets of experiments with each mayfly species were conducted, following an unreplicated regression design. Dechlorinated tap water was used as the water source. Experiments in the Channels were repeated to determine experimental variability. Results were compared statistically by testing for overlap of 95% confidence limits (95%Cls) of EC50 values. The differences between A. auriculata EC50 values in the different systems were statistically significant (no overlap of 95%CLs), but they were not more variable than has been considered normal for biological systems (Coefficient of variation 20.1 %; ratio of greatest EC50 / smallest EC50 1.63). The differences were not related to the scale or the average current velocity characteristic of each stream design (average current velocity LASUs - Raceways - Channels 0.090 - 0.083 - 0.038 m/s). The Channels proved to be most efficient with regard to practical performance as they are portable and easily transportable, user-friendly, reliable, splash-free, cost effective to construct, and can easily be adapted to specific requirements. These systems are therefore recommended for regular use. The suitability of the two mayfly species for routine toxicity testing was evaluated. A. auriculata EC50 values showed a significant negative correlation with the corresponding average body-size (range 1476 - 1610 μm, mean 1555 μm). The different average body-sizes probably reflected the abundance of a certain size range present in the Palmiet River at the time of collection. Both species reacted similarly to Na₂S0₄ (similar slopes of the toxicity curves), identifying this salt as a slow acting toxicant. A. sudafricanum populations were more sensitive to Na₂S0₄ (EC50 3.404 g/L) than A. auriculata (EC50 8.090 g/L), probably because of its smaller body-size (mean 709 μm) and a lack of extremely tolerant individuals. In comparison to other freshwater macro invertebrates, including the standard toxicity test organism Daphnia spp., both mayfly species seemed to be moderately tolerant of Na₂S0₄; therefore there was no particular advantage to using these indigenous taxa rather than Daphnia spp. An assessment of the effects of elevated salinity/TDS levels on the test taxa yielded preliminary insights. A NaCI-EC50 for A. sudafricanum could be extrapolated and suggested a higher sensitivity to Na₂S0₄ than to NaCl. When Na₂S0₄ EC50 values of both species were compared to selected TDS levels of South African rivers, 4. auriculata would mostly not be affected, but A. sudafricanum might occasionally suffer from sub-lethal effects, depending on the sulphate proportion of the TDS. The South African guideline for TDS seemed to protect both species sufficiently.
- Full Text:
- Date Issued: 2000
- Authors: Binder, Markus
- Date: 2000
- Subjects: Water -- Pollution -- Toxicology , Toxicology -- Research , Aquatic organisms -- Effect of water pollution on , Sodium sulfate , Mayflies
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5690 , http://hdl.handle.net/10962/d1005376 , Water -- Pollution -- Toxicology , Toxicology -- Research , Aquatic organisms -- Effect of water pollution on , Sodium sulfate , Mayflies
- Description: Three artificial stream designs, termed Large Artificial Stream Units (LASUs), Raceways, and Channels, at two major scales (1700 L, 12.5 L and 20 L recirculated volume) were developed at the Institute for Water Research, Rhodes University, Grahamstown, in order to explore the possibilities of using indigenous rheophilic macroinvertebrates in routine toxicity tests. This study compared these systems, using 96h-EC50 values from sodium sulphate toxicity tests as the experimental response. Two local Ephemeroptera (Leptophlebiidae: Adenophlebia auriculata Eaton, and Baetidae: Afroptilum sudafricanum Lestage) were evaluated for their suitability in routine toxicity tests; and the possible effects of elevated salinity levels in South African rivers on the test species were assessed. Two sets of experiments with each mayfly species were conducted, following an unreplicated regression design. Dechlorinated tap water was used as the water source. Experiments in the Channels were repeated to determine experimental variability. Results were compared statistically by testing for overlap of 95% confidence limits (95%Cls) of EC50 values. The differences between A. auriculata EC50 values in the different systems were statistically significant (no overlap of 95%CLs), but they were not more variable than has been considered normal for biological systems (Coefficient of variation 20.1 %; ratio of greatest EC50 / smallest EC50 1.63). The differences were not related to the scale or the average current velocity characteristic of each stream design (average current velocity LASUs - Raceways - Channels 0.090 - 0.083 - 0.038 m/s). The Channels proved to be most efficient with regard to practical performance as they are portable and easily transportable, user-friendly, reliable, splash-free, cost effective to construct, and can easily be adapted to specific requirements. These systems are therefore recommended for regular use. The suitability of the two mayfly species for routine toxicity testing was evaluated. A. auriculata EC50 values showed a significant negative correlation with the corresponding average body-size (range 1476 - 1610 μm, mean 1555 μm). The different average body-sizes probably reflected the abundance of a certain size range present in the Palmiet River at the time of collection. Both species reacted similarly to Na₂S0₄ (similar slopes of the toxicity curves), identifying this salt as a slow acting toxicant. A. sudafricanum populations were more sensitive to Na₂S0₄ (EC50 3.404 g/L) than A. auriculata (EC50 8.090 g/L), probably because of its smaller body-size (mean 709 μm) and a lack of extremely tolerant individuals. In comparison to other freshwater macro invertebrates, including the standard toxicity test organism Daphnia spp., both mayfly species seemed to be moderately tolerant of Na₂S0₄; therefore there was no particular advantage to using these indigenous taxa rather than Daphnia spp. An assessment of the effects of elevated salinity/TDS levels on the test taxa yielded preliminary insights. A NaCI-EC50 for A. sudafricanum could be extrapolated and suggested a higher sensitivity to Na₂S0₄ than to NaCl. When Na₂S0₄ EC50 values of both species were compared to selected TDS levels of South African rivers, 4. auriculata would mostly not be affected, but A. sudafricanum might occasionally suffer from sub-lethal effects, depending on the sulphate proportion of the TDS. The South African guideline for TDS seemed to protect both species sufficiently.
- Full Text:
- Date Issued: 2000
An evaluation of the life science curriculum in Namibia and its development through stakeholders' perceptions of ʺlearner centred educationʺ
- Authors: Kristensen, Jesper Olsson
- Date: 2000
- Subjects: Life science project Curriculum evaluation -- Namibia Environmental education Educational change -- Namibia Life sciences -- Study and teaching -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1527 , http://hdl.handle.net/10962/d1003409
- Description: Following Independence in 1991 Namibia embarked on a major reform of the entire education system. The reform was perceived as a way of redressing the apartheid legacy and bringing about a democratic learner centred education for all. At the same time the reform was also seen as a prime vehicle to bring about sustainable development through incorporating relevant environmental education into various carrier subjects. One such carrier has been the subject Life Science, which is compulsory from Grade 8 to Grade 10. The Life Science Project was a joint venture between the Ministry of Education and Ibis, a Danish Development NGO, established to develop and support the implementation of Life Science in junior secondary schools. This half-thesis is an evaluation of the Life Science Project through an analysis of the central assumptions on which the Life Science curriculum is based and by investigating different stakeholders’ perceptions and understanding of the learner centred approach adopted by the curriculum. Three questions have guided this research: 1. Are there curriculum models that are more conducive for reform and change than others? 2. Do stakeholders and curriculum developers in Namibia understand the theory of social constructivism, and the systemic implications such an approach has for the education system? 3. Which approach to environmental education complements a transformative curriculum and the changes outlined in policy? From the research carried out in this half-thesis, it would appear that the Namibian education system and the Life Science curriculum suffers from what could be termed “ideological confusion”. Confusion in the sense that there are marked inconsistencies between policy and praxis, between the stated goals and aims of the reform and the curriculum designed to achieve these. This confusion is further exacerbated by various stakeholders’ different interpretations of both policy and the systemic implications the reform policy has on education. In this half-thesis I argue that embarking on an objectives driven model of curriculum cannot bring about change and transformation of the Namibian education system. I further argue that, by not having considered and implemented the necessary systemic changes to the education system, Namibia has, in fact, developed a child centred education system which is fundamentally different from a learner centred education system. Finally, I argue that environmental education, through the subject Life Science, set within an objectives driven, Child Centred Education system is inappropriate for and unable to address the need for developing an environmentally literate citizenry who are able to take informed decisions in order to address the environmental crisis and bring forth a more sustainable future.
- Full Text:
- Date Issued: 2000
- Authors: Kristensen, Jesper Olsson
- Date: 2000
- Subjects: Life science project Curriculum evaluation -- Namibia Environmental education Educational change -- Namibia Life sciences -- Study and teaching -- Evaluation
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1527 , http://hdl.handle.net/10962/d1003409
- Description: Following Independence in 1991 Namibia embarked on a major reform of the entire education system. The reform was perceived as a way of redressing the apartheid legacy and bringing about a democratic learner centred education for all. At the same time the reform was also seen as a prime vehicle to bring about sustainable development through incorporating relevant environmental education into various carrier subjects. One such carrier has been the subject Life Science, which is compulsory from Grade 8 to Grade 10. The Life Science Project was a joint venture between the Ministry of Education and Ibis, a Danish Development NGO, established to develop and support the implementation of Life Science in junior secondary schools. This half-thesis is an evaluation of the Life Science Project through an analysis of the central assumptions on which the Life Science curriculum is based and by investigating different stakeholders’ perceptions and understanding of the learner centred approach adopted by the curriculum. Three questions have guided this research: 1. Are there curriculum models that are more conducive for reform and change than others? 2. Do stakeholders and curriculum developers in Namibia understand the theory of social constructivism, and the systemic implications such an approach has for the education system? 3. Which approach to environmental education complements a transformative curriculum and the changes outlined in policy? From the research carried out in this half-thesis, it would appear that the Namibian education system and the Life Science curriculum suffers from what could be termed “ideological confusion”. Confusion in the sense that there are marked inconsistencies between policy and praxis, between the stated goals and aims of the reform and the curriculum designed to achieve these. This confusion is further exacerbated by various stakeholders’ different interpretations of both policy and the systemic implications the reform policy has on education. In this half-thesis I argue that embarking on an objectives driven model of curriculum cannot bring about change and transformation of the Namibian education system. I further argue that, by not having considered and implemented the necessary systemic changes to the education system, Namibia has, in fact, developed a child centred education system which is fundamentally different from a learner centred education system. Finally, I argue that environmental education, through the subject Life Science, set within an objectives driven, Child Centred Education system is inappropriate for and unable to address the need for developing an environmentally literate citizenry who are able to take informed decisions in order to address the environmental crisis and bring forth a more sustainable future.
- Full Text:
- Date Issued: 2000
An examination of the drafting-responding process used to develop students' writing in an English Language for Academic Purposes Course
- Authors: Quinn, Lynn
- Date: 2000
- Subjects: English language -- Study and teaching (Higher) -- Foreign speakers , Rhodes University -- Academic Development Programme , Academic writing -- Study and teaching (Higher) -- South Africa , Educational anthropology -- South Africa , Educational sociology -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2359 , http://hdl.handle.net/10962/d1002642 , English language -- Study and teaching (Higher) -- Foreign speakers , Rhodes University -- Academic Development Programme , Academic writing -- Study and teaching (Higher) -- South Africa , Educational anthropology -- South Africa , Educational sociology -- South Africa
- Description: Many students when they arrive at university do not possess the “cultural capital” (Bourdieu 1977) which is favoured by the institution. The purpose of the English Language for Academic Purposes (ELAP) course and the drafting-responding process is to help students to begin to acquire the “cultural capital” required to succeed at university. The research reported on in this thesis examined the drafting-responding process as it is used to develop students’ writing in the ELAP course at Rhodes University. The process involved students submitting drafts of their essays on which they received constructive and formative feedback from their ELAP tutor. This feedback was then used to revise their essays before a final version was submitted for assessment. The research took the form of a case study with an essentially interpretive orientation. I examined the drafts (with the tutor’s comments) and final versions of seven students’ ELAP essays. Additional data was obtained by interviewing the students and the tutor. Underpinning my beliefs regarding the role of writing in learning as well as my orientation to research is an understanding of knowledge and learning as being socially constructed. All writing is embedded in and dependent on, not only the immediate social circumstances, but also the broader social and cultural context. In analysing and discussing the data in this research I used Halliday’s (1985) definition of context, in which he draws a broad distinction between the immediate context of situation and the broader context of culture The research findings showed that the drafting-responding process can help students with the process of developing the academic literacy they need in order to write essays within specific situational contexts, in this case, the context of the ELAP course. In addition, at a broader level, it can help students to begin the process of being initiated into the culture of the university as a whole.
- Full Text:
- Date Issued: 2000
- Authors: Quinn, Lynn
- Date: 2000
- Subjects: English language -- Study and teaching (Higher) -- Foreign speakers , Rhodes University -- Academic Development Programme , Academic writing -- Study and teaching (Higher) -- South Africa , Educational anthropology -- South Africa , Educational sociology -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2359 , http://hdl.handle.net/10962/d1002642 , English language -- Study and teaching (Higher) -- Foreign speakers , Rhodes University -- Academic Development Programme , Academic writing -- Study and teaching (Higher) -- South Africa , Educational anthropology -- South Africa , Educational sociology -- South Africa
- Description: Many students when they arrive at university do not possess the “cultural capital” (Bourdieu 1977) which is favoured by the institution. The purpose of the English Language for Academic Purposes (ELAP) course and the drafting-responding process is to help students to begin to acquire the “cultural capital” required to succeed at university. The research reported on in this thesis examined the drafting-responding process as it is used to develop students’ writing in the ELAP course at Rhodes University. The process involved students submitting drafts of their essays on which they received constructive and formative feedback from their ELAP tutor. This feedback was then used to revise their essays before a final version was submitted for assessment. The research took the form of a case study with an essentially interpretive orientation. I examined the drafts (with the tutor’s comments) and final versions of seven students’ ELAP essays. Additional data was obtained by interviewing the students and the tutor. Underpinning my beliefs regarding the role of writing in learning as well as my orientation to research is an understanding of knowledge and learning as being socially constructed. All writing is embedded in and dependent on, not only the immediate social circumstances, but also the broader social and cultural context. In analysing and discussing the data in this research I used Halliday’s (1985) definition of context, in which he draws a broad distinction between the immediate context of situation and the broader context of culture The research findings showed that the drafting-responding process can help students with the process of developing the academic literacy they need in order to write essays within specific situational contexts, in this case, the context of the ELAP course. In addition, at a broader level, it can help students to begin the process of being initiated into the culture of the university as a whole.
- Full Text:
- Date Issued: 2000
An examination of the facilitatory role for environmental education of conservancies
- Authors: Law-Jackson, Danielle
- Date: 2000
- Subjects: Environmental education Nature conservation -- South Africa Wildlife conservation -- South Africa Conservation of natural resources -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1529 , http://hdl.handle.net/10962/d1003411
- Description: This study examines the possibilities within the conservancy movement for the facilitation of environmental education. By means of a case study approach, a conservancy in the Northern Cape and the conservancy movement within the Free State provinces are compared with a view to elucidating factors militating against and promoting the success of environmental education programmes. The current lack of research in isolated rural areas is discussed. Re-orientation of perspectives regarding the value of conservancy-based environmental education within governmental, academic and local circles is recommended.
- Full Text:
- Date Issued: 2000
- Authors: Law-Jackson, Danielle
- Date: 2000
- Subjects: Environmental education Nature conservation -- South Africa Wildlife conservation -- South Africa Conservation of natural resources -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1529 , http://hdl.handle.net/10962/d1003411
- Description: This study examines the possibilities within the conservancy movement for the facilitation of environmental education. By means of a case study approach, a conservancy in the Northern Cape and the conservancy movement within the Free State provinces are compared with a view to elucidating factors militating against and promoting the success of environmental education programmes. The current lack of research in isolated rural areas is discussed. Re-orientation of perspectives regarding the value of conservancy-based environmental education within governmental, academic and local circles is recommended.
- Full Text:
- Date Issued: 2000
An exploration of female physicality and psyche and how these inform art-making
- Authors: Poole, Tanya Katherine
- Date: 2000
- Subjects: Women artists , Women artists -- Psychology , Rego, Paula -- Interviews , Feminism , Women -- Sexual behavior , Sherman, Cindy , Saville, Jenny, 1970-
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2419 , http://hdl.handle.net/10962/d1002215 , Women artists , Women artists -- Psychology , Rego, Paula -- Interviews , Feminism , Women -- Sexual behavior , Sherman, Cindy , Saville, Jenny, 1970-
- Description: This thesis proposes that female physicality informs the psyche and thus in turn, art-making. My argument will be shown to be apposite and informative to the discussion of the work of Paula Rego, Jenny Saville and Cindy Sherman. Furthermore such an understanding is helpful to a reading of my practice. In examining issues of identity, which contribute to the formulation of a distinctly female psyche, I will base my critique on the philosophical positions of Sartre, de Beauvoir and Paglia.
- Full Text:
- Date Issued: 2000
- Authors: Poole, Tanya Katherine
- Date: 2000
- Subjects: Women artists , Women artists -- Psychology , Rego, Paula -- Interviews , Feminism , Women -- Sexual behavior , Sherman, Cindy , Saville, Jenny, 1970-
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2419 , http://hdl.handle.net/10962/d1002215 , Women artists , Women artists -- Psychology , Rego, Paula -- Interviews , Feminism , Women -- Sexual behavior , Sherman, Cindy , Saville, Jenny, 1970-
- Description: This thesis proposes that female physicality informs the psyche and thus in turn, art-making. My argument will be shown to be apposite and informative to the discussion of the work of Paula Rego, Jenny Saville and Cindy Sherman. Furthermore such an understanding is helpful to a reading of my practice. In examining issues of identity, which contribute to the formulation of a distinctly female psyche, I will base my critique on the philosophical positions of Sartre, de Beauvoir and Paglia.
- Full Text:
- Date Issued: 2000
An exploration of the interaction between integration and discipline in a former model C school in East London
- Authors: Smulders, Heidi
- Date: 2000
- Subjects: School discipline -- South Africa -- Eastern Cape -- Case studies , Multicultural education -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3061 , http://hdl.handle.net/10962/d1002570 , School discipline -- South Africa -- Eastern Cape -- Case studies , Multicultural education -- South Africa -- Case studies
- Description: Educators work in dynamic contexts which reflect the social and political circumstances of the time. Since the African National Congress was elected to govern in 1994, educators working in former Model C schools have been particularly affected by changes in the law regarding education. The South African Schools Act of 1996 prohibited discriminating in any way against learners applying for admission to schools. This has resulted in cultural and racial integration occurring at all former Model C schools. The use of corporal punishment in schools was also prohibited in 1996. This study attempts to obtain an understanding of the interaction between integration and discipline which was identified at a particular Model C school in East London. It also aims to obtain educators' understandings of the challenges of integration and discipline at this school. Following an in-depth pilot study of the school's detention records for 1998, twenty-two out of sixty educators at the school participated in the research by responding to written questionnaires. It is argued that two different approaches to integration are presently used by educators. These are identified and discussed, namely assimilatory education and multicultural education. The need for consistency between educators in their approaches to integration and discipline is also addressed.
- Full Text:
- Date Issued: 2000
- Authors: Smulders, Heidi
- Date: 2000
- Subjects: School discipline -- South Africa -- Eastern Cape -- Case studies , Multicultural education -- South Africa -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3061 , http://hdl.handle.net/10962/d1002570 , School discipline -- South Africa -- Eastern Cape -- Case studies , Multicultural education -- South Africa -- Case studies
- Description: Educators work in dynamic contexts which reflect the social and political circumstances of the time. Since the African National Congress was elected to govern in 1994, educators working in former Model C schools have been particularly affected by changes in the law regarding education. The South African Schools Act of 1996 prohibited discriminating in any way against learners applying for admission to schools. This has resulted in cultural and racial integration occurring at all former Model C schools. The use of corporal punishment in schools was also prohibited in 1996. This study attempts to obtain an understanding of the interaction between integration and discipline which was identified at a particular Model C school in East London. It also aims to obtain educators' understandings of the challenges of integration and discipline at this school. Following an in-depth pilot study of the school's detention records for 1998, twenty-two out of sixty educators at the school participated in the research by responding to written questionnaires. It is argued that two different approaches to integration are presently used by educators. These are identified and discussed, namely assimilatory education and multicultural education. The need for consistency between educators in their approaches to integration and discipline is also addressed.
- Full Text:
- Date Issued: 2000
An informed community's perception of the impact of digital technology on the credibility of news photography
- Authors: Làzaro, Angelique Maria
- Date: 2000
- Subjects: Photojournalism -- Moral and ethical aspects , Digital media , Photojournalists , Photography -- Digital techniques
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3451 , http://hdl.handle.net/10962/d1002905 , Photojournalism -- Moral and ethical aspects , Digital media , Photojournalists , Photography -- Digital techniques
- Description: South African photojournalists’ perception of digital technology’s impact on the credibility of news photographs is investigated in this study. Digital technology has the capabilities to produce “manipulated” photographs that appear realistic and credible. Credibility is dependent on a variety of factors including codes of realism and codes of production, which fit conventional codes of photographic representation. Manipulation is the act of deviating from accepted codes of photographic representation that may jeopardise the credibility of news photography. This thesis proposes a new theoretical framework that encompasses existing theories of semiotics, ideology, naturalism, realism and credibility. These theories underpin the definitions and discussion on manipulation and credibility. A descriptive survey is used which attempts to discover photojournalists’ views towards credibility. This research draws on qualitative research methods using a largely qualitative questionnaire, which generates both qualitative and quantitative data. The questions are formulated around two case studies of digitally manipulated photographs. The trends and responses in the research data are connected and discussed. The findings of this study are discussed in terms of credibility, awareness of the digital changes, the reason for the changes, the role of a caption, deletion techniques and background changes. The empirical situation is analysed in relation to the theoretical discussions and this study’s theorisation of photographic representation.
- Full Text:
- Date Issued: 2000
- Authors: Làzaro, Angelique Maria
- Date: 2000
- Subjects: Photojournalism -- Moral and ethical aspects , Digital media , Photojournalists , Photography -- Digital techniques
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3451 , http://hdl.handle.net/10962/d1002905 , Photojournalism -- Moral and ethical aspects , Digital media , Photojournalists , Photography -- Digital techniques
- Description: South African photojournalists’ perception of digital technology’s impact on the credibility of news photographs is investigated in this study. Digital technology has the capabilities to produce “manipulated” photographs that appear realistic and credible. Credibility is dependent on a variety of factors including codes of realism and codes of production, which fit conventional codes of photographic representation. Manipulation is the act of deviating from accepted codes of photographic representation that may jeopardise the credibility of news photography. This thesis proposes a new theoretical framework that encompasses existing theories of semiotics, ideology, naturalism, realism and credibility. These theories underpin the definitions and discussion on manipulation and credibility. A descriptive survey is used which attempts to discover photojournalists’ views towards credibility. This research draws on qualitative research methods using a largely qualitative questionnaire, which generates both qualitative and quantitative data. The questions are formulated around two case studies of digitally manipulated photographs. The trends and responses in the research data are connected and discussed. The findings of this study are discussed in terms of credibility, awareness of the digital changes, the reason for the changes, the role of a caption, deletion techniques and background changes. The empirical situation is analysed in relation to the theoretical discussions and this study’s theorisation of photographic representation.
- Full Text:
- Date Issued: 2000
An investigation into dopamine-melatonin interactions in the rat Corpus striatum and pineal gland: a possible pineal-striatal axis
- Authors: Boyd, Clinton Shane
- Date: 2000
- Subjects: Pineal gland -- Research Melatonin Dopamine -- Physiological effect Dopamine Brain chemistry Rats -- Physiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3906 , http://hdl.handle.net/10962/d1003965
- Description: Dysfunction of central dopaminergic systems has been implicated in neuroendocrine, neurodegenerative and psychiatric disorders. Monoamine oxidase and catechol-Omethyltransferase represent the key catabolic enzymes of dopamine, terminating neurotransmission following synaptic release of this catecholamine. Thus, both enzymes have been associated with the pathology of dopaminergic systems and represent therapeutic targets elf enormous clinical importance. Some neuroendocrine and circadian effects of melatonin have been attributed to an antidopamimetic effect of this pineal hormone in the hypothalamus and pituitary. Furthermore, both melatonin and dopamine modulate the behavioural output of the mesencephalic dopaminergic pathways of the basal ganglia, including movement disorders. However, the biochemical basis for the tonic inhibitory effect of melatonin in the nigro-striatal pathway has been poorly delineated. Thus, this study determined whether melatonin influences dopaminergic function in the corpus striatum of the Wistar rat by modulating monoamine oxidase and catecholO- methyltransferase activity. Reciprocally, the putative existence of an intrapineal dopaminergic system was investigated by determining the effect of selective dopaminergic agents, R-( -)apomorphine, haloperidol and dopamine, on indole metabolism of the pineal gland. The akinetic state of drug-induced catalepsy was employed as an animal model of Parkinson's disease to probe the neurotransmitter systems involved in the behavioural effects of melatonin. Indole metabolism was a reliable indicator of state-dependent metabolic fluxes in pineal gland function. These included a robust diurnal and seasonal variation in N-acetylserotonin and melatonin biosynthesis, and photoperiod- and drug-induced alterations of Inftabolism. The predominant changes could be attributed to an effect on serotonin N-acetyltransferase activity and/or the melatoninl5-methoxytryptophol ratio. Pineal 5-methoxyindole biosynthesis was determined primarily by the bioavailability of the corresponding 5-hydroxyindole and its affinity for hydroxyindole-O-methyltransferase. Evidence was found for the negative feedback or paracrine control of pineal indole metabolism by melatonin. A high inter-individual variability was observed in the biosynthesis of N-acetylserotonin and melatonin biosynthesis, and the weight of the pineal glands. Accordingly, the rats could be classified as either high or low capacity producers of these two indoles. R-(-)-apomorphine and dopamine in vitro, but not acute haloperidol in vivo, had dose- and phase-dependent effects on pineal indole metabolism. The predominant effect was a suppression of the scotophase-dependent induction ofN-acetylserotonin and melatonin biosynthesis by dopamine and R-( -)-apomorphine. It is postulated that these agonists inhibited nocturnal N-acetyltransferase activity via postsynaptic pineal D2 or D2-like receptors. The observed modulatory nature of the intrapineal dopaminergic system suggests that dopamine may be involved in the long-term regulation of pineal indole biosynthesis. Several lines of evidence are presented that the activity of striatal monoamine oxidase A and catechol-O-methyltransferase, represented predominantly by the soluble isoform, is statedependent and regulated in vivo by endogenous melatonin. Firstly, both enzymes showed a daynight variation in activity. Secondly, acute and subchronic administration and photoperiod manipulation studies indicated that both exogenous and endogenous melatonin inhibited each enzyme in a chronotypic fashion, with a more robust effect against catechol- -methyltransferase. The intensity of the in vivo effects was critically dependent on the dose, duration, route and the phase-timing of administration during the light dark cycle, and the length of the exposure to constant light. Melatonin in vitro had no effect on basal or Mg2+ -induced catechol-Omethyltransferase activity. Thus, it is proposed that the in vivo effects of the hormone can be attributed to a time-dependent change in the amount of active molecules of this enzyme. In contrast, melatonin and numerous other endogenous indolic compounds were found to be reversible inhibitors of striatal monoamine oxidase A in vitro. Structure-activity modeling revealed that the 5-methoxy moiety on the indole nucleus and substitution of the free primary amine of these compounds were the principal determinants of the potency and time-dependency of inhibition. Thus melatonin most likely has a direct inhibitory effect in vivo at the level of the active site of monoamine oxidase A. Exogenous melatonin alone had no cataleptogenic potential whereas a variety of behavioural responses were observed following intraperitoneal administration of y-hydroxybutyrate. The latter responses were state-dependent with day-night variations in intensity. Furthermore, yhydroxybutyrate stimulated melatonin biosynthesis during the photophase both in vitro and in vivo. These results point to a possible involvement of melatonin in the behavioural and neurochemical effects of y-hydroxybutyrate. Thus the general conclusion is that dopamine and melatonin display functional antagonism at the level of the pineal gland and corpus striatum of the Wistar rats. Therefore melatonin may be an important homeostatic modulator of dopaminergic neurotransmission throu~out the central nervous system. Furthermore, the putative existence of a functional pineal-striatal axis would greatly strengthen the argument for a holistic concept of brain homeostasis. The ability of endogenous melatonin to regulate monoamine oxidase A and catechol-O-methyltransferase may represent an alternative strategy for the treatment of disorders associated with these enzymes.
- Full Text:
- Date Issued: 2000
- Authors: Boyd, Clinton Shane
- Date: 2000
- Subjects: Pineal gland -- Research Melatonin Dopamine -- Physiological effect Dopamine Brain chemistry Rats -- Physiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3906 , http://hdl.handle.net/10962/d1003965
- Description: Dysfunction of central dopaminergic systems has been implicated in neuroendocrine, neurodegenerative and psychiatric disorders. Monoamine oxidase and catechol-Omethyltransferase represent the key catabolic enzymes of dopamine, terminating neurotransmission following synaptic release of this catecholamine. Thus, both enzymes have been associated with the pathology of dopaminergic systems and represent therapeutic targets elf enormous clinical importance. Some neuroendocrine and circadian effects of melatonin have been attributed to an antidopamimetic effect of this pineal hormone in the hypothalamus and pituitary. Furthermore, both melatonin and dopamine modulate the behavioural output of the mesencephalic dopaminergic pathways of the basal ganglia, including movement disorders. However, the biochemical basis for the tonic inhibitory effect of melatonin in the nigro-striatal pathway has been poorly delineated. Thus, this study determined whether melatonin influences dopaminergic function in the corpus striatum of the Wistar rat by modulating monoamine oxidase and catecholO- methyltransferase activity. Reciprocally, the putative existence of an intrapineal dopaminergic system was investigated by determining the effect of selective dopaminergic agents, R-( -)apomorphine, haloperidol and dopamine, on indole metabolism of the pineal gland. The akinetic state of drug-induced catalepsy was employed as an animal model of Parkinson's disease to probe the neurotransmitter systems involved in the behavioural effects of melatonin. Indole metabolism was a reliable indicator of state-dependent metabolic fluxes in pineal gland function. These included a robust diurnal and seasonal variation in N-acetylserotonin and melatonin biosynthesis, and photoperiod- and drug-induced alterations of Inftabolism. The predominant changes could be attributed to an effect on serotonin N-acetyltransferase activity and/or the melatoninl5-methoxytryptophol ratio. Pineal 5-methoxyindole biosynthesis was determined primarily by the bioavailability of the corresponding 5-hydroxyindole and its affinity for hydroxyindole-O-methyltransferase. Evidence was found for the negative feedback or paracrine control of pineal indole metabolism by melatonin. A high inter-individual variability was observed in the biosynthesis of N-acetylserotonin and melatonin biosynthesis, and the weight of the pineal glands. Accordingly, the rats could be classified as either high or low capacity producers of these two indoles. R-(-)-apomorphine and dopamine in vitro, but not acute haloperidol in vivo, had dose- and phase-dependent effects on pineal indole metabolism. The predominant effect was a suppression of the scotophase-dependent induction ofN-acetylserotonin and melatonin biosynthesis by dopamine and R-( -)-apomorphine. It is postulated that these agonists inhibited nocturnal N-acetyltransferase activity via postsynaptic pineal D2 or D2-like receptors. The observed modulatory nature of the intrapineal dopaminergic system suggests that dopamine may be involved in the long-term regulation of pineal indole biosynthesis. Several lines of evidence are presented that the activity of striatal monoamine oxidase A and catechol-O-methyltransferase, represented predominantly by the soluble isoform, is statedependent and regulated in vivo by endogenous melatonin. Firstly, both enzymes showed a daynight variation in activity. Secondly, acute and subchronic administration and photoperiod manipulation studies indicated that both exogenous and endogenous melatonin inhibited each enzyme in a chronotypic fashion, with a more robust effect against catechol- -methyltransferase. The intensity of the in vivo effects was critically dependent on the dose, duration, route and the phase-timing of administration during the light dark cycle, and the length of the exposure to constant light. Melatonin in vitro had no effect on basal or Mg2+ -induced catechol-Omethyltransferase activity. Thus, it is proposed that the in vivo effects of the hormone can be attributed to a time-dependent change in the amount of active molecules of this enzyme. In contrast, melatonin and numerous other endogenous indolic compounds were found to be reversible inhibitors of striatal monoamine oxidase A in vitro. Structure-activity modeling revealed that the 5-methoxy moiety on the indole nucleus and substitution of the free primary amine of these compounds were the principal determinants of the potency and time-dependency of inhibition. Thus melatonin most likely has a direct inhibitory effect in vivo at the level of the active site of monoamine oxidase A. Exogenous melatonin alone had no cataleptogenic potential whereas a variety of behavioural responses were observed following intraperitoneal administration of y-hydroxybutyrate. The latter responses were state-dependent with day-night variations in intensity. Furthermore, yhydroxybutyrate stimulated melatonin biosynthesis during the photophase both in vitro and in vivo. These results point to a possible involvement of melatonin in the behavioural and neurochemical effects of y-hydroxybutyrate. Thus the general conclusion is that dopamine and melatonin display functional antagonism at the level of the pineal gland and corpus striatum of the Wistar rats. Therefore melatonin may be an important homeostatic modulator of dopaminergic neurotransmission throu~out the central nervous system. Furthermore, the putative existence of a functional pineal-striatal axis would greatly strengthen the argument for a holistic concept of brain homeostasis. The ability of endogenous melatonin to regulate monoamine oxidase A and catechol-O-methyltransferase may represent an alternative strategy for the treatment of disorders associated with these enzymes.
- Full Text:
- Date Issued: 2000
An investigation into short course accreditation through the South African Qualification Authority
- Authors: Mackenzie, Ian
- Date: 2000
- Subjects: Adult education -- South Africa Elementary education of adults -- South Africa School management and organization -- South Africa Guguletu Comprehensive School South African Qualifications Authority
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1600 , http://hdl.handle.net/10962/d1003482
- Description: This research project offers an analysis of the Adult Basic Education and Training Directorate in the Eastern Cape Province. The Bush Models are described and critiqued and then used as a tool for analysis. Other organisational models are described and used to add depth to the analysis. The choice of analysing the Adult Basic Education and Training Directorate comes both from a professional desire to know and understand this organisation more fully, as well as the importance of stressing that the definition of education organisations does not stop at school, colleges and universities, but includes the government bodies which are a key part of the sector. This assignment therefore explores both the features of a government department as well as the appropriateness of using Bush’s models in this context and draws on other organisational theory--Introduction.
- Full Text:
- Date Issued: 2000
- Authors: Mackenzie, Ian
- Date: 2000
- Subjects: Adult education -- South Africa Elementary education of adults -- South Africa School management and organization -- South Africa Guguletu Comprehensive School South African Qualifications Authority
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1600 , http://hdl.handle.net/10962/d1003482
- Description: This research project offers an analysis of the Adult Basic Education and Training Directorate in the Eastern Cape Province. The Bush Models are described and critiqued and then used as a tool for analysis. Other organisational models are described and used to add depth to the analysis. The choice of analysing the Adult Basic Education and Training Directorate comes both from a professional desire to know and understand this organisation more fully, as well as the importance of stressing that the definition of education organisations does not stop at school, colleges and universities, but includes the government bodies which are a key part of the sector. This assignment therefore explores both the features of a government department as well as the appropriateness of using Bush’s models in this context and draws on other organisational theory--Introduction.
- Full Text:
- Date Issued: 2000
An investigation into the effects of socio-economic and education factors on WAIS-III performance in a stratified South African sample
- Authors: Kemp, Ryan
- Date: 2000
- Subjects: Wechsler Adult Intelligence Scale -- South Africa , Intelligence tests -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3002 , http://hdl.handle.net/10962/d1002511 , Wechsler Adult Intelligence Scale -- South Africa , Intelligence tests -- South Africa
- Description: The present study examined the effects of socio-economic status, quality and level of education on performance on the Wechsler Adult Intelligence Scale 3rd Edition r.:w AIS-III). The study was conducted within the context of the present Human Sciences Research Council (HSRC) W AIS-III standardisation process, cross-cultural psychometric research and the notion of test-wiseness. A South African sample (N = 68) comprising African first language (n = 40) and English first language (n = 28) participants, stratified for age (19 - 30 years), gender and educational attainment (Matric and Graduate) were utilised. Effects due to quality of education were determined by dividing the African language participants into those with private/model C schooling (n = 20) and those with DET schooling (n = 20). Effects due to level of education were determined by dividing the entire sample into those with Matric level education (n = 34) and those with Graduate level education (n = 34). Detailed demographic and socio-economic information were recorded for all participants, who completed the entire American version of the W AIS-III. Results revealed a highly significant positive correlation between high socio-economic status and W AIS-III Full Scale IQ. In addition the respective impact of the relatively poor quality of education and lower level of educational attainment on W AIS-III performance was substantial. These results were discussed in terms of their implications for cross-cultural research, the HSRC standardisation of the W AIS-III and the practical use of the W AIS-III in neuropsychological assessment.
- Full Text:
- Date Issued: 2000
- Authors: Kemp, Ryan
- Date: 2000
- Subjects: Wechsler Adult Intelligence Scale -- South Africa , Intelligence tests -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3002 , http://hdl.handle.net/10962/d1002511 , Wechsler Adult Intelligence Scale -- South Africa , Intelligence tests -- South Africa
- Description: The present study examined the effects of socio-economic status, quality and level of education on performance on the Wechsler Adult Intelligence Scale 3rd Edition r.:w AIS-III). The study was conducted within the context of the present Human Sciences Research Council (HSRC) W AIS-III standardisation process, cross-cultural psychometric research and the notion of test-wiseness. A South African sample (N = 68) comprising African first language (n = 40) and English first language (n = 28) participants, stratified for age (19 - 30 years), gender and educational attainment (Matric and Graduate) were utilised. Effects due to quality of education were determined by dividing the African language participants into those with private/model C schooling (n = 20) and those with DET schooling (n = 20). Effects due to level of education were determined by dividing the entire sample into those with Matric level education (n = 34) and those with Graduate level education (n = 34). Detailed demographic and socio-economic information were recorded for all participants, who completed the entire American version of the W AIS-III. Results revealed a highly significant positive correlation between high socio-economic status and W AIS-III Full Scale IQ. In addition the respective impact of the relatively poor quality of education and lower level of educational attainment on W AIS-III performance was substantial. These results were discussed in terms of their implications for cross-cultural research, the HSRC standardisation of the W AIS-III and the practical use of the W AIS-III in neuropsychological assessment.
- Full Text:
- Date Issued: 2000
An investigation into the influence of the environment on spawning aggregations and jig catches of chokka squid Loligo Vulgaris reynaudii off the south coast of South Africa
- Authors: Schön, Pieter-Jan
- Date: 2000
- Subjects: Squids -- Spawning , Squid fisheries -- South Africa , Squids , Shellfish fisheries -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5378 , http://hdl.handle.net/10962/d1016369
- Description: Erratic and highly variable catches in the South African chokka squid Loligo vulgaris reynaudii fishery, cause socio-economic hardship for the industry and uncertainty for resource managers. Catch forecasting can reduce this problem as it is believed that catch variability is strongly influenced by environmental factors. In this study, data were collected at varying temporal and spatial scales. Data for the hourly time-scale study were collected from 1996-1998, aboard commercial vessels, whilst for the longer time-scales, data were extracted for Kromme Bay (a single fishing area) from existing databases (1991-1998) that were comprised of compulsory catch returns and oceanographic data. The environment-catch relationship for chokka squid on the inshore spawning grounds was then investigated using multiple correlation and regression analysis, analysis of variance, contingency table analysis and cross-correlation statistical techniques. This simple, direct, 'black box' statistical approach was relatively successful in developing a predictive capability. On a short time-scale (hourly), the regression model accounted for 32% of the variability in catch, with turbidity the main determinant (13%). On a daily monthly time-scale, the best prediction model was on a monthly scale, accounting for 40% of the variability in catch. The principal determinant, bottom temperature anomaly (11 %), was found to lag one month forward. Seasonal and diel catch variations induced changes in the relative importance of turbidity, water temperature and wind direction on catches. A strong, positive relationship was found between easterly winds (which cause upwelling) and catch, particularly in summer. Catch rates, however, decreased with an increase in turbidity. The correlation between temperature and catch was generally negative, however, higher catches were associated with a temperature range of 13-18°C. Highest catch rates were associated with easterly winds, zero turbidity conditions and sea surface temperatures from 15.0-16.9°C. Selected case studies (in situ observations) suggested that upwelling and turbidity events act as environmental triggers for the initiation or termination of the spawning process, respectively. A holistic approach is required to improve predictive capability of chokka squid abundance. Although short-term predictability remains essential (i.e. hourly-scale), future research should concentrate on long-term prediction models (e.g., monthly time-scales) involving greater spatial variation, which are the most important for management.
- Full Text:
- Date Issued: 2000
- Authors: Schön, Pieter-Jan
- Date: 2000
- Subjects: Squids -- Spawning , Squid fisheries -- South Africa , Squids , Shellfish fisheries -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5378 , http://hdl.handle.net/10962/d1016369
- Description: Erratic and highly variable catches in the South African chokka squid Loligo vulgaris reynaudii fishery, cause socio-economic hardship for the industry and uncertainty for resource managers. Catch forecasting can reduce this problem as it is believed that catch variability is strongly influenced by environmental factors. In this study, data were collected at varying temporal and spatial scales. Data for the hourly time-scale study were collected from 1996-1998, aboard commercial vessels, whilst for the longer time-scales, data were extracted for Kromme Bay (a single fishing area) from existing databases (1991-1998) that were comprised of compulsory catch returns and oceanographic data. The environment-catch relationship for chokka squid on the inshore spawning grounds was then investigated using multiple correlation and regression analysis, analysis of variance, contingency table analysis and cross-correlation statistical techniques. This simple, direct, 'black box' statistical approach was relatively successful in developing a predictive capability. On a short time-scale (hourly), the regression model accounted for 32% of the variability in catch, with turbidity the main determinant (13%). On a daily monthly time-scale, the best prediction model was on a monthly scale, accounting for 40% of the variability in catch. The principal determinant, bottom temperature anomaly (11 %), was found to lag one month forward. Seasonal and diel catch variations induced changes in the relative importance of turbidity, water temperature and wind direction on catches. A strong, positive relationship was found between easterly winds (which cause upwelling) and catch, particularly in summer. Catch rates, however, decreased with an increase in turbidity. The correlation between temperature and catch was generally negative, however, higher catches were associated with a temperature range of 13-18°C. Highest catch rates were associated with easterly winds, zero turbidity conditions and sea surface temperatures from 15.0-16.9°C. Selected case studies (in situ observations) suggested that upwelling and turbidity events act as environmental triggers for the initiation or termination of the spawning process, respectively. A holistic approach is required to improve predictive capability of chokka squid abundance. Although short-term predictability remains essential (i.e. hourly-scale), future research should concentrate on long-term prediction models (e.g., monthly time-scales) involving greater spatial variation, which are the most important for management.
- Full Text:
- Date Issued: 2000
An investigation into the neuroprotective properties of ibuprofen
- Lambat, Zaynab Y, Conrad, Natasha, Anoopkumar-Dukie, Shailendra, Walker, Roderick B, Daya, Santylal
- Authors: Lambat, Zaynab Y , Conrad, Natasha , Anoopkumar-Dukie, Shailendra , Walker, Roderick B , Daya, Santylal
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184335 , vital:44209 , xlink:href="https://doi.org/10.1023/A:1011115006856"
- Description: There is increasing evidence suggesting a protective role for anti-inflammatory medications in neurological disorders such as Alzheimer's disease (AD). While there has not been any direct evidence for this, a number of clinical studies indicate that those patients who have had a history of nonsteroidal anti-inflammatory use, have a lower incidence of AD. Since there is currently no evidence on the mechanism by which these agents offer possible neuroprotection, we investigated the potential neuroprotective properties of the nonsteroidal anti-inflammatory drug, ibuprofen, by examining whether this agent could reduce lipid peroxidation and superoxide radical generation. Quinolinic acid and cyanide, known neurotoxins, were used to induce lipid peroxidation and superoxide anion formation respectively, in rat brain homogenate. The results show that ibuprofen significantly (p more than 0.05) reduced quinolinic acid-induced lipid peroxidation and cyanide-induced superoxide production. The results of the present report therefore suggest a possible mechanism for the neuroprotective effect of ibuprofen.
- Full Text: false
- Date Issued: 2000
- Authors: Lambat, Zaynab Y , Conrad, Natasha , Anoopkumar-Dukie, Shailendra , Walker, Roderick B , Daya, Santylal
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184335 , vital:44209 , xlink:href="https://doi.org/10.1023/A:1011115006856"
- Description: There is increasing evidence suggesting a protective role for anti-inflammatory medications in neurological disorders such as Alzheimer's disease (AD). While there has not been any direct evidence for this, a number of clinical studies indicate that those patients who have had a history of nonsteroidal anti-inflammatory use, have a lower incidence of AD. Since there is currently no evidence on the mechanism by which these agents offer possible neuroprotection, we investigated the potential neuroprotective properties of the nonsteroidal anti-inflammatory drug, ibuprofen, by examining whether this agent could reduce lipid peroxidation and superoxide radical generation. Quinolinic acid and cyanide, known neurotoxins, were used to induce lipid peroxidation and superoxide anion formation respectively, in rat brain homogenate. The results show that ibuprofen significantly (p more than 0.05) reduced quinolinic acid-induced lipid peroxidation and cyanide-induced superoxide production. The results of the present report therefore suggest a possible mechanism for the neuroprotective effect of ibuprofen.
- Full Text: false
- Date Issued: 2000
An investigation into tools and protocols for commercial audio web-site creation
- Authors: Ndinga, S'busiso Simon
- Date: 2000
- Subjects: Web sites -- Design , Digital libraries , Internet -- Security measures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4621 , http://hdl.handle.net/10962/d1006488 , Web sites -- Design , Digital libraries , Internet -- Security measures
- Description: This thesis presents a feasibility study of a Web-based digital music library and purchasing system. It investigates the current status of the enabling technologies for developing such a system. An analysis of various Internet audio codecs, streaming audio protocols, Internet credit card payment security methods, and ways for accessing remote Web databases is presented. The objective of the analysis is to determine the viability and the economic benefits of using these technologies when developing systems that facilitate music distribution over the Internet. A prototype of a distributed digital music library and purchasing system named WAPS (for Web-based Audio Purchasing System) was developed and implemented in the Java programming language. In this thesis both the physical and the logical component elements of WAPS are explored in depth so as to provide an insight into the inherent problems of creating such a system, as well as the overriding benefits derived from the creation of such a system.
- Full Text:
- Date Issued: 2000
- Authors: Ndinga, S'busiso Simon
- Date: 2000
- Subjects: Web sites -- Design , Digital libraries , Internet -- Security measures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4621 , http://hdl.handle.net/10962/d1006488 , Web sites -- Design , Digital libraries , Internet -- Security measures
- Description: This thesis presents a feasibility study of a Web-based digital music library and purchasing system. It investigates the current status of the enabling technologies for developing such a system. An analysis of various Internet audio codecs, streaming audio protocols, Internet credit card payment security methods, and ways for accessing remote Web databases is presented. The objective of the analysis is to determine the viability and the economic benefits of using these technologies when developing systems that facilitate music distribution over the Internet. A prototype of a distributed digital music library and purchasing system named WAPS (for Web-based Audio Purchasing System) was developed and implemented in the Java programming language. In this thesis both the physical and the logical component elements of WAPS are explored in depth so as to provide an insight into the inherent problems of creating such a system, as well as the overriding benefits derived from the creation of such a system.
- Full Text:
- Date Issued: 2000
An investigation of learners' perceptions of homework in relation to the learning of mathematics : case studies in the northern townships of Port Elizabeth
- Authors: Wendt, Gabriele Erika
- Date: 2000
- Subjects: Homework -- South Africa -- Port Elizabeth Mathematics -- Study and teaching -- South Africa -- Port Elizabeth Mathematics -- Study and teaching -- South Africa -- Case studies Education and state -- South Africa Education -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1635 , http://hdl.handle.net/10962/d1003517
- Description: Matriculation pass rates in South Africa, especially in Mathematics, have been poor. The literature and personal experience suggests that a problem with homework may be a factor in this. In order to discover how Port Elizabeth learners from ex-DET schools perceived and experienced Mathematics homework, and the nature of such homework, ten case studies of Grade 11 learners were done. While conducting and analyzing the case studies, a pattern emerged from the findings, which together with some new questions, needed to be explored on a larger sample population. In order to do this and to be able to generalize the findings, four follow-up studies in the form of surveys on Mathematics homework were conducted at nine schools. These studies involved a learner questionnaire, a teacher questionnaire, the timing of learners as they did set Mathematical problems and the analysis of common errors made by the learners while doing the problems. The findings revealed that learners received too little homework too infrequently and did it inefficiently and ineffectively. The learners worked too slowly, did not complete the homework, left out the difficult problems and made numerous unnecessary mistakes. However, most of the learners claimed to have enough time available to do their homework and spent approximately one hour on Mathematics homework when it had been assigned. Many of the misconceptions and the resultant errors originated from work that should have been well covered in previous grades. However, parts of the syllabi were omitted in previous grades and completion of the syllabus and homework was only seriously considered in Grade 12. Some implications of the findings for educational practice and further research are discussed.
- Full Text:
- Date Issued: 2000
- Authors: Wendt, Gabriele Erika
- Date: 2000
- Subjects: Homework -- South Africa -- Port Elizabeth Mathematics -- Study and teaching -- South Africa -- Port Elizabeth Mathematics -- Study and teaching -- South Africa -- Case studies Education and state -- South Africa Education -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1635 , http://hdl.handle.net/10962/d1003517
- Description: Matriculation pass rates in South Africa, especially in Mathematics, have been poor. The literature and personal experience suggests that a problem with homework may be a factor in this. In order to discover how Port Elizabeth learners from ex-DET schools perceived and experienced Mathematics homework, and the nature of such homework, ten case studies of Grade 11 learners were done. While conducting and analyzing the case studies, a pattern emerged from the findings, which together with some new questions, needed to be explored on a larger sample population. In order to do this and to be able to generalize the findings, four follow-up studies in the form of surveys on Mathematics homework were conducted at nine schools. These studies involved a learner questionnaire, a teacher questionnaire, the timing of learners as they did set Mathematical problems and the analysis of common errors made by the learners while doing the problems. The findings revealed that learners received too little homework too infrequently and did it inefficiently and ineffectively. The learners worked too slowly, did not complete the homework, left out the difficult problems and made numerous unnecessary mistakes. However, most of the learners claimed to have enough time available to do their homework and spent approximately one hour on Mathematics homework when it had been assigned. Many of the misconceptions and the resultant errors originated from work that should have been well covered in previous grades. However, parts of the syllabi were omitted in previous grades and completion of the syllabus and homework was only seriously considered in Grade 12. Some implications of the findings for educational practice and further research are discussed.
- Full Text:
- Date Issued: 2000
An investigation of male and female cognitive ability on the WAIS-III
- Authors: Muirhead, Joanne
- Date: 2000
- Subjects: Wechsler Adult Intelligence Scale , Sex differences (Psychology) , Intelligence tests -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3028 , http://hdl.handle.net/10962/d1002537 , Wechsler Adult Intelligence Scale , Sex differences (Psychology) , Intelligence tests -- South Africa
- Description: This study, which formed part of a larger research project, investigated the effect of gender on test performance on the Wechsler Adult Intelligence Scale - Third Edition (WAIS-III). The WAIS-III was administered to a sample of 68 participants in the Eastern Cape following the initiative of the Human Sciences Research Council to standardise the WAIS-III for a South African population. The participants, aged 19 to 30, were stratified according to language of origin (African or English First Language), educational attainment (matriculant or graduate), quality of education (Department of Education and Training or private/"Model C" school) and gender. Analyses of variance and two sample t tests were used to compare male and female test performance. For the total sample, no significant difference between males and females on Verbal, Performance and Full Scale IQ were found. On the factor indices, females scored marginally higher than males on Processing Speed at a level which was approaching significance (p = 0.105), but no significant differences were found. On subtest performance, females significantly outperformed males on Digit Symbol (p = 0.020). Differences which were approaching significance were found on Information (p = 0.133) in favour of males, and on Matrix Reasoning (p = 0.092) in favour of females. For subgroups of the total sample, the most significant differences in test performance were found for the African First Language private/"Model C" school cohort in favour of females. Thus the overriding implication that emerged from this research was that on this relatively highly educated sample, no significant gender differences in cognitive ability were apparent.
- Full Text:
- Date Issued: 2000
- Authors: Muirhead, Joanne
- Date: 2000
- Subjects: Wechsler Adult Intelligence Scale , Sex differences (Psychology) , Intelligence tests -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3028 , http://hdl.handle.net/10962/d1002537 , Wechsler Adult Intelligence Scale , Sex differences (Psychology) , Intelligence tests -- South Africa
- Description: This study, which formed part of a larger research project, investigated the effect of gender on test performance on the Wechsler Adult Intelligence Scale - Third Edition (WAIS-III). The WAIS-III was administered to a sample of 68 participants in the Eastern Cape following the initiative of the Human Sciences Research Council to standardise the WAIS-III for a South African population. The participants, aged 19 to 30, were stratified according to language of origin (African or English First Language), educational attainment (matriculant or graduate), quality of education (Department of Education and Training or private/"Model C" school) and gender. Analyses of variance and two sample t tests were used to compare male and female test performance. For the total sample, no significant difference between males and females on Verbal, Performance and Full Scale IQ were found. On the factor indices, females scored marginally higher than males on Processing Speed at a level which was approaching significance (p = 0.105), but no significant differences were found. On subtest performance, females significantly outperformed males on Digit Symbol (p = 0.020). Differences which were approaching significance were found on Information (p = 0.133) in favour of males, and on Matrix Reasoning (p = 0.092) in favour of females. For subgroups of the total sample, the most significant differences in test performance were found for the African First Language private/"Model C" school cohort in favour of females. Thus the overriding implication that emerged from this research was that on this relatively highly educated sample, no significant gender differences in cognitive ability were apparent.
- Full Text:
- Date Issued: 2000
An investigation of parental non-involvement in the governance of a Duncan Village school and its implications for the management of the school : a case study
- Authors: Ndlazi, Sibongile Mandisa
- Date: 2000
- Subjects: School management and organization -- South Africa -- Eastern Cape Education -- Parent participation -- South Africa Education -- Parent participation -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1639 , http://hdl.handle.net/10962/d1003521
- Description: This study explores the perceptions that parents have about their non-involvement in the governance of a Duncan Village High School, and considers the implications of such perceptions for the management of the school. Recent discussions on Radio Talk Shows and articles written in local newspapers indicate that Black parents have generally not been involved in the education of their children at the traditionally Black schools. Parental non-involvement also emerges as a strong theme in recent research. However, most of the research and media coverage focuses on school management's perceptions of the reasons and consequences of such non-involvement. The parents' voices have rarely been heard. Against this background, as well as the fact that the South African Schools Act presents a strong case for the involvement of parents in school governance and management, a phenomenological investigation was conducted at a traditionally Black Duncan Village High School. I chose phenomenology because I believed this approach has the potential for revealing my respondents' attitudes and perceptions. The sample consisted of four parent members of the school governing body who were key informants. The respondents were subjected to unstructured interviews which were held at their homes. The interviews probed the background and reasons for their lack of involvement, and the possible implications ofthis non-involvement for school management. The most significant of the wealth of findings is that parental non-involvement is linked to the historical background of the culture of non-participation of Black people which was created and encouraged by the successive White Governments in South Africa.
- Full Text:
- Date Issued: 2000
- Authors: Ndlazi, Sibongile Mandisa
- Date: 2000
- Subjects: School management and organization -- South Africa -- Eastern Cape Education -- Parent participation -- South Africa Education -- Parent participation -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1639 , http://hdl.handle.net/10962/d1003521
- Description: This study explores the perceptions that parents have about their non-involvement in the governance of a Duncan Village High School, and considers the implications of such perceptions for the management of the school. Recent discussions on Radio Talk Shows and articles written in local newspapers indicate that Black parents have generally not been involved in the education of their children at the traditionally Black schools. Parental non-involvement also emerges as a strong theme in recent research. However, most of the research and media coverage focuses on school management's perceptions of the reasons and consequences of such non-involvement. The parents' voices have rarely been heard. Against this background, as well as the fact that the South African Schools Act presents a strong case for the involvement of parents in school governance and management, a phenomenological investigation was conducted at a traditionally Black Duncan Village High School. I chose phenomenology because I believed this approach has the potential for revealing my respondents' attitudes and perceptions. The sample consisted of four parent members of the school governing body who were key informants. The respondents were subjected to unstructured interviews which were held at their homes. The interviews probed the background and reasons for their lack of involvement, and the possible implications ofthis non-involvement for school management. The most significant of the wealth of findings is that parental non-involvement is linked to the historical background of the culture of non-participation of Black people which was created and encouraged by the successive White Governments in South Africa.
- Full Text:
- Date Issued: 2000
An investigative case study of the introduction of democratic decision-making within an East London secondary school
- Authors: Carelse, Garth Craig
- Date: 2000
- Subjects: School management and organization -- South Africa Decision making -- Cast studies Education and state Ebenezer Majombozi High
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1920 , http://hdl.handle.net/10962/d1007404
- Description: The move towards greater democracy and participation in our education system is legislated quite succinctly in our South African Schools Act. The Act furthermore, and more importantly for this case study, posits that decision-making should be democratic in nature and our schools should eventually become governed in a collaborative and co-operative manner. Other policy texts such as the Labour Relations Act and the South African Constitution canonise the demand for a democratic South African society. This study investigates how democratic decision-making practices are taking place in an East London Secondary School namely Ebenezer Majombozi High. Even though distinct links exist between management and governance arms of schools, this study concentrates predominantly on decision-making within the school governing body and touches briefly on management thinking trends as a theoretical background to the kind of management at the school. What makes the school interesting as a case study is its rich history and its location in a deprived and impoverished township environment. The school was also part of the ex-Department of Education and Training, the black educational department of the past apartheid state. The kind of research undertaken was in the form of unstructured personal interviews with influential stakeholders at the school. Some of these stakeholders fonn part of the school governing body and the questions asked probed forms of governance at the school and how decision-making impacted on the overall school governance. The research findings acknowledges that decision-making does occur democratically at the school but that the practical implementation of positive consensual decisions are rarely realized. The school governing body only meets to deal with crises underpinned by a lack of learning and teaching and has not even debated the policies within the South African Schools Act. The study also argues that only by building capacity within the school and empowering the stakeholders, can constructive participation by all become a reality.
- Full Text:
- Date Issued: 2000
- Authors: Carelse, Garth Craig
- Date: 2000
- Subjects: School management and organization -- South Africa Decision making -- Cast studies Education and state Ebenezer Majombozi High
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1920 , http://hdl.handle.net/10962/d1007404
- Description: The move towards greater democracy and participation in our education system is legislated quite succinctly in our South African Schools Act. The Act furthermore, and more importantly for this case study, posits that decision-making should be democratic in nature and our schools should eventually become governed in a collaborative and co-operative manner. Other policy texts such as the Labour Relations Act and the South African Constitution canonise the demand for a democratic South African society. This study investigates how democratic decision-making practices are taking place in an East London Secondary School namely Ebenezer Majombozi High. Even though distinct links exist between management and governance arms of schools, this study concentrates predominantly on decision-making within the school governing body and touches briefly on management thinking trends as a theoretical background to the kind of management at the school. What makes the school interesting as a case study is its rich history and its location in a deprived and impoverished township environment. The school was also part of the ex-Department of Education and Training, the black educational department of the past apartheid state. The kind of research undertaken was in the form of unstructured personal interviews with influential stakeholders at the school. Some of these stakeholders fonn part of the school governing body and the questions asked probed forms of governance at the school and how decision-making impacted on the overall school governance. The research findings acknowledges that decision-making does occur democratically at the school but that the practical implementation of positive consensual decisions are rarely realized. The school governing body only meets to deal with crises underpinned by a lack of learning and teaching and has not even debated the policies within the South African Schools Act. The study also argues that only by building capacity within the school and empowering the stakeholders, can constructive participation by all become a reality.
- Full Text:
- Date Issued: 2000
Analysis of strategies used by an organisation to manage conflict
- Authors: Lourens, Ann Sharon
- Date: 2000
- Subjects: Conflict management , Negotiation in business , Mediation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10828 , http://hdl.handle.net/10948/18 , Conflict management , Negotiation in business , Mediation
- Description: This research study addresses the problem of determining the strategies that can be used to manage conflict effectively. To achieve this objective a comprehensive literature study was performed to determine the views on conflict and various models of conflict. The study also included the reasons for and sources of conflict and the effects of conflict on an organisation. The next step was to identify the conflict management strategies that were revealed by the literature study. The appropriate conflict handling styles, how to improve organisational practices and special rules and structures were discussed as well as various suggestions from different authors on how to resolve a conflict situation. Based on the information obtained from the literature study a model was developed to serve as a guide to organisations to manage conflict effectively. Managers from a specific organisation were requested to complete questionnaires in order to determine the strategies used by their organisation to manage conflict. The questionnaire was developed in accordance with the findings from the research. The answers of the respondents were analysed and compared to the findings of the literature study. The information obtained from the literature study and from the respondents resulted in various recommendations and conclusions. The previously mentioned model that was developed was applied to the organisation, specifically addressing the pertinent issues as indicated by the respondents.
- Full Text:
- Date Issued: 2000
- Authors: Lourens, Ann Sharon
- Date: 2000
- Subjects: Conflict management , Negotiation in business , Mediation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10828 , http://hdl.handle.net/10948/18 , Conflict management , Negotiation in business , Mediation
- Description: This research study addresses the problem of determining the strategies that can be used to manage conflict effectively. To achieve this objective a comprehensive literature study was performed to determine the views on conflict and various models of conflict. The study also included the reasons for and sources of conflict and the effects of conflict on an organisation. The next step was to identify the conflict management strategies that were revealed by the literature study. The appropriate conflict handling styles, how to improve organisational practices and special rules and structures were discussed as well as various suggestions from different authors on how to resolve a conflict situation. Based on the information obtained from the literature study a model was developed to serve as a guide to organisations to manage conflict effectively. Managers from a specific organisation were requested to complete questionnaires in order to determine the strategies used by their organisation to manage conflict. The questionnaire was developed in accordance with the findings from the research. The answers of the respondents were analysed and compared to the findings of the literature study. The information obtained from the literature study and from the respondents resulted in various recommendations and conclusions. The previously mentioned model that was developed was applied to the organisation, specifically addressing the pertinent issues as indicated by the respondents.
- Full Text:
- Date Issued: 2000
Anka niogon deme
- Saly Sidibe, Harouna Bary (arrangement), Adama Drame (guitar solo), Batass (bass guitar), Harouna Samake ((N'goni), Lamine Camara (electric piano), Mamadou Koita (Djembe), Sidi Coulibaly (drums), Amadou Taore dit Adez (flute), Awa Diabate, Sanata Doumbie (chorus), Ali Landoure
- Authors: Saly Sidibe , Harouna Bary (arrangement) , Adama Drame (guitar solo) , Batass (bass guitar) , Harouna Samake ((N'goni) , Lamine Camara (electric piano) , Mamadou Koita (Djembe) , Sidi Coulibaly (drums) , Amadou Taore dit Adez (flute) , Awa Diabate, Sanata Doumbie (chorus) , Ali Landoure
- Date: 2000
- Subjects: Popular music , Popular music--Mali--1991-2000 , Africa Mali Wassalou f-ml
- Language: French
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/127322 , vital:36000 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDCO3-01
- Description: Singing accompanied by guitar and N'goni, electric piano and flute
- Full Text: false
- Date Issued: 2000
- Authors: Saly Sidibe , Harouna Bary (arrangement) , Adama Drame (guitar solo) , Batass (bass guitar) , Harouna Samake ((N'goni) , Lamine Camara (electric piano) , Mamadou Koita (Djembe) , Sidi Coulibaly (drums) , Amadou Taore dit Adez (flute) , Awa Diabate, Sanata Doumbie (chorus) , Ali Landoure
- Date: 2000
- Subjects: Popular music , Popular music--Mali--1991-2000 , Africa Mali Wassalou f-ml
- Language: French
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/127322 , vital:36000 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDCO3-01
- Description: Singing accompanied by guitar and N'goni, electric piano and flute
- Full Text: false
- Date Issued: 2000
Anka Niogon Deme
- Saly Sidibe, Harouna Bary (arrangement), Adama Drame (guitar solo), Amadou Taore dit Adez (flute), Batoss (bass guitar), Lamine Camara (electric piano), Mamadou Koita (Djembe), Harouna Samake (N'goni), Sidi Coulibaly (drums), Awa Diabate, Sanota Doumbie (chorus), Ali Landoure
- Authors: Saly Sidibe , Harouna Bary (arrangement) , Adama Drame (guitar solo) , Amadou Taore dit Adez (flute) , Batoss (bass guitar) , Lamine Camara (electric piano) , Mamadou Koita (Djembe) , Harouna Samake (N'goni) , Sidi Coulibaly (drums) , Awa Diabate, Sanota Doumbie (chorus) , Ali Landoure
- Date: 2000
- Subjects: Popular music , Popular music--Mali--1991-2000 , Africa Mali Wassoulou f-ml
- Language: Bambara
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/127412 , vital:36010 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDCO3-10
- Description: Singing accompanied by guitar and N'goni, electric piano and flute
- Full Text: false
- Date Issued: 2000
- Authors: Saly Sidibe , Harouna Bary (arrangement) , Adama Drame (guitar solo) , Amadou Taore dit Adez (flute) , Batoss (bass guitar) , Lamine Camara (electric piano) , Mamadou Koita (Djembe) , Harouna Samake (N'goni) , Sidi Coulibaly (drums) , Awa Diabate, Sanota Doumbie (chorus) , Ali Landoure
- Date: 2000
- Subjects: Popular music , Popular music--Mali--1991-2000 , Africa Mali Wassoulou f-ml
- Language: Bambara
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/127412 , vital:36010 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDCO3-10
- Description: Singing accompanied by guitar and N'goni, electric piano and flute
- Full Text: false
- Date Issued: 2000