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The effect of combined vitamin E succinate and ascorbic acid supplementation on growth and cyclooxygenase expression in murine melanoma (BL6) cells

  • Authors: Van Rooyen, Megan Lynne
  • Date: 1999
  • Subjects: Vitamin E , Vitamin C , Melanoma
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3982 , http://hdl.handle.net/10962/d1004041 , Vitamin E , Vitamin C , Melanoma
  • Description: This thesis examines the effect of combined vitamin E succinate and Asc supplementation on the in vitro growth of a non-malignant monkey kidney (LLCMK) and a malignant melanoma (BL6) cell line, with nutritional concentration ranges of 5-20µg/ml and 25-50µg/ml respectively. Vitamin E and C are thought to interact synergistically to inhibit tumour cell growth by virtue of their antioxidant properties, whereby they quench free radicals and terminate lipid peroxidation. Furthermore vitamin E and C are thought to modulate the biosynthetic pathways in arachidonic acid metabolism at a number of different points. This may also offer a means of regulating tumour cell growth. It is well documented that vitamin E and C are distributed in the lipid and aqueous phases in the cell respectively. However, the cells need to obtain the vitamins from the environment in which they are found in order to exert a growth inhibitory effect. Supplementation of combined vitamin E succinate and Asc on BL6 and LLCMK cells resulted in a significant increase in LLCMK cell growth, and a significant decrease in cell growth was observed in BL6 cells. Vitamin E succinate in its esterified form cannot function as an antioxidant and requires the cleavage of the succinate to become an active antioxidant. The metabolism of vitamin E succinate to form free vitamin E in LLCMK and BL6 cells resulted in the cleavage of the succinate group from the vitamin E molecule in BL6 cells only, thus suggesting that an esterase may be present in BL6 cells. This would allow for a synergistic interaction between the two vitamins. The arachidonic acid cascade generates a family of bioactive lipids that modulate diverse physiological and pathological responses including tumour growth and promotion. The enzyme prostaglandin endoperoxide synthase (PGHS) or cyclooxygenase (Cox) is the key enzyme in the biosynthetic pathway leading to the formation of prostaglandins. Two enzyme isoforms of Cox have been identified, Cox 1 and Cox 2. Supplementation with vitamin E succinate and Asc at a combination 20:25µg/ml respectively resulted in a trend of increasing Cox activity over 12 hours suggesting that vitamin E and Asc have a stimulatory effect on Cox activity in BL6 cells. The inhibitors of Cox 2, dexamethasone, showed a decreasing trend in Cox activity at the 20:25µg/ml combination, while cycloheximide showed an initial stimulatory effect and then a gradual decrease in Cox activity. The elimination of the Cox activity by dexamethasone suggests that transcriptional regulation may be occurring in BL6 cells. We examined by Northern blot analysis whether combined supplementation of vitamin E succinate and Asc caused an elevation of Cox 2 RNA expression in BL6 cells. An inducible effect of Cox 2 was observed after 2 hours of supplementation with a combination of vitamin E succinate and Asc in BL6 cells, however the results are inconclusive and further studies are required to substantiate this finding.
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The effect of diet and age-at-weaning on growth and survival of clownfish Amphiprion percula (Pisces : Pomacentridae)

  • Authors: Gordon, Andrew K
  • Date: 1999
  • Subjects: Anemonefishes , Pomacentridae , Fishes -- Growth
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5270 , http://hdl.handle.net/10962/d1005114 , Anemonefishes , Pomacentridae , Fishes -- Growth
  • Description: The aim of this study was to improve the rearing of common clownfish Amphiprion percula, by weaning juveniles from a live feed to a formulated feed as early as possible, while still maintaining good growth and survival. The growth response of A. percula to a formulated dry feed was initially investigated. There was no difference in growth rate of juveniles fed a formulated feed, and the formulated feed supplemented with either Artemia or a Donax serra / Penaeus indicus combination. Amphiprion percula readily consumed the formulated feed, and the fishmeal/casein combination appeared an acceptable protein source. As the amount of protein included in a diet can have a profound effect on growth, the optimal dietary protein level for juvenile A. percula was investigated by feeding semipurified diets containing graded levels of protein, ranging from 40-65%. There was no difference in the growth rates of juveniles fed the various diets, however all diets promoted good growth with an average weight gain of 419%, and thus for the purposes of this study the diet formulation was deemed adequate. The histological study of the digestive system of larval A. percula revealed that the alimentary canal was advanced at hatching and that larvae start exogenous feeding immediately. Three days after hatch (DAH) the yolk sac is completely absorbed. In the hind-gut epithelium of 5-day-old larvae small supranuclear inclusion vacuoles appear, suggesting pinocytotic digestion, and by 7 DAH gastric glands are established in the epithelium of the stomach. Nine DAH supranuclear inclusion vacuoles appear in the epithelium of the mid-gut, indicating extracellular digestion and absorption across the lumen. As pinocytotic digestion of protein is less efficient than extracellular digestion, especially in the case of formulated feeds, it was hypothesised that the digestive system of A. percula could only effectively digest formulated feeds 9 DAH onwards. The two weaning experiments designed to test this hypothesis revealed that A. percula was able to utilise the formulated feed, without reduction in survival, from 7 DAH onwards. However, in terms of growth, the optimal time to wean juveniles from the live feed to the formulated dry feed was between 15 to 20 DAH. As A. percula accept a formulated feed and can benefit nutritionally from it, the dependence of larvae and juveniles on live feed can be reduced. This study has shown that the rearing of A. percula can been simplified and improved by weaning from 7 DAH with no reduction in survival, and from 15 to 20 DAH with no reduction in growth.
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The haunted bedroom: female sexual identity in Gothic literature, 1790-1820

  • Authors: Rae, Angela Lynn
  • Date: 1999
  • Subjects: Wollstonecraft, Mary, 1759-1797 -- Criticism and interpretation , Shelley, Mary Wollstonecraft, 1797-1851 -- Criticism and interpretation , Gothic literature , Women and literature , Feminism and literature , Radcliffe, Ann Ward, 1764-1823 Criticism and interpretation
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2251 , http://hdl.handle.net/10962/d1002294 , Wollstonecraft, Mary, 1759-1797 -- Criticism and interpretation , Shelley, Mary Wollstonecraft, 1797-1851 -- Criticism and interpretation , Gothic literature , Women and literature , Feminism and literature , Radcliffe, Ann Ward, 1764-1823 Criticism and interpretation
  • Description: This thesis explores the relationship between the Female Gothic novel of the late eighteenth and early nineteenth century and the social context of women at that time. In the examination of the primary works of Ann Radcliffe, Mary Wollstonecraft and Mary Shelley, this study investigates how these female writers work within the Gothic genre to explore issues related to the role of women in their society, in particular those concerned with sexual identity. It is contended that the Gothic genre provides these authors with the ideal vehicle through which to critique the patriarchal definition of the female, a definition which confines and marginalizes women, denying the female any sexual autonomy. The Introduction defines the scope of the thesis by delineating the differences between the Female Gothic and the Male Gothic. Arguing that the Female Gothic shuns the voyeuristic victimisation of women which characterizes much of the Male Gothic, it is contended that the Female Gothic is defined by its interest in, and exploration of, issues which concern the status of women in a patriarchy. It is asserted that it is this concern with female gender roles that connects the overtly radical work of Mary Wollstonecraft with the oblique critique evident in her contemporary, Ann Radcliffe’s, novels. It is these concerns too, which haunt Mary Shelley’s texts, published two decades later. Chapter One outlines the status of women in the patriarchal society of the late eighteenth century, a period marked by political and social upheaval. This period saw the increasing division of men and women into the “separate spheres” of the public and domestic worlds, and the consequent birth of the ideal of “Angel in the House” which became entrenched in the nineteenth century. The chapter examines how women writers were influenced by this social context and what effect it had on the presentation of female characters in their work, in particular in terms of their depiction of motherhood. Working from the premise that, in order to fully understand the portrayal of female sexuality in the texts, the depiction of the male must be examined, Chapter Two analyses the male characters in terms of their relationship to the heroines and/or the concept of the “feminine”. Although the male characters differ from text to text and author to author, it is argued that in their portrayal of “heroes and villains” the authors were providing a critique of the patriarchal system. While some of the texts depict male characters that challenge traditional stereotypes concerning masculinity, others outline the disastrous and sometimes fatal consequences for both men and women of the rigid gender divisions which disallow the male access to the emotional realm restricted by social prescriptions to the private, domestic world of the female. It is contended that, as such, all of the texts assert the necessity for male and female, masculine and feminine to be united on equal terms. Chapter Three interprets the heroine’s journey through sublime landscapes and mysterious buildings as a journey from childhood innocence to sexual maturity, illustrating the intrinsic link that exists between the settings of Gothic novels and female sexuality. The chapter first examines the authors’ use of the Burkean concept of the sublime and contends that the texts offer a significant revision of the concept. In contrast to Burke’s overtly masculinist definition of the sublime, the texts assert that the female can and does have access to it, and that this access can be used to overcome patriarchal oppression. Secondly, an analysis of the image of the castle and related structures reveals that they can symbolise both the patriarchy and the feminine body. Contending that the heroine’s experiences within these structures enable her to move from innocence to experience, it is asserted that the knowledge that she gains, during her journeys, of herself and of society allows her to assert her independence as a sexually adult woman.
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The impact of water as a security issue on the Middle East peace process: 1991-1996

  • Authors: Kaniaru, Wanjiku
  • Date: 1999
  • Subjects: Middle East -- Politics and government -- 1979- , Arab-Israeli conflict, 1993- -- Peace , Water-supply -- Political aspects -- Middle East , Natural resources -- International cooperation
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2785 , http://hdl.handle.net/10962/d1002995 , Middle East -- Politics and government -- 1979- , Arab-Israeli conflict, 1993- -- Peace , Water-supply -- Political aspects -- Middle East , Natural resources -- International cooperation
  • Description: In recent years, there has been increasing realisation that resource based conflicts constitute one of the most salient threats to the survival of mankind, namely, water. In particular, the fundamental link between water and security can no longer be ignored given the indispensable role of water in the sustenance of human life as well as crucial sectors of agriculture and industry. Since the flow of water does not respect political boundaries, co-operation in the utilisation of dwindling supplies remains the most sustainable option for the future in an era of ecological interdependence. This thesis endeavours to investigate the impact of water as a security issue on the Middle East peace process. This is done within the theoretical framework that is provided by the schools of complex interdependence and new security studies. With the demise of the cold war, and the emergence of an expanded security agenda, water is an important non-military threat especially in the Middle East region. However, even with an expanded security agenda, the case of the Middle East suggests that it remains difficult to discard the hierarchy of security issues advocated by the Realists. The ongoing debate between the schools of complex interdependence and Realism is instructive in determining whether co-operation over water issues, considered "low" politics, is attainable in the absence of resolving "high" politics concerns of territory and security. Given its profound security implications for the Middle East region, water has been accorded a central role in both the bilateral and multilateral peace negotiations. In the context of water scarcity, and rising demographic patterns, the role of water as a facilitator of regional co-operation remains critical. However, for multilateral co-operation over water resources to become a tangible reality, it is the contention of this thesis that both "low" politics issues of water and "high" polities concerns of territory as well as security must be addressed simultaneously.
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The importance of personal and collective resources in coping with stressors related to industrial action at the Coldstream sawmill

  • Authors: Besseling, Elizabeth Anne
  • Date: 1999
  • Subjects: Stress (Psychology) , Stress (Physiology) , Industrial relations -- South Africa -- Case studies , Coldstream (South africa)
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2932 , http://hdl.handle.net/10962/d1002441 , Stress (Psychology) , Stress (Physiology) , Industrial relations -- South Africa -- Case studies , Coldstream (South africa)
  • Description: The main purpose of the study is to investigate whether the stress response moderators served as effective variables in reducing the stress of the strike. For instance, if individuals differ in' their ability to actualise resources, does someone with a high SOC utilise friendships or supportive relationships more than someone with a low SOC? Does someone who has a high score for religious practice become less depressed when faced with a significant stressor than someone less involved in church activities?
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The isolation and characterisation of thermostable hydantoinases from hydantoinase-producing bacteria

  • Authors: Phehane, Vuyisile Ntosi
  • Date: 1999
  • Subjects: Hydantoin , Bacteria -- Physiology , Enzymes
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3998 , http://hdl.handle.net/10962/d1004058 , Hydantoin , Bacteria -- Physiology , Enzymes
  • Description: In order to characterise thermostable hydantoin-hydrolysing enzymes from bacteria, locally-isolated thermophilic organisms were screened for the ability to convert hydantoin to N-carbamylglycine at 55°C using the hydantoinase enzyme. Cell disruption of a selected strain, RU-20-15, was conducted by French pressing to release enzyme from within the cell. In all of the experiments conducted, the amounts of product were low. In view of the low yields of products formed by the thermophiles, a previously-isolated Gram negative strain, RU-KM3L was selected from a number of mesophiles by screening for hydantoinase and carbamylase activity over a 40-55°C temperature range. Hydantoin conversion at 40°C using crude extract from pressed cells of this organism was similar to conversion at 50°C, and therefore subsequent assays were conducted at the higher temperature. The growth kinetics of RU-KM3L cells were studied and the enzyme activities of the extracts were compared in complete and chemically-defined media. The results suggested that the optimal time to harvest cells was at early stationary phase, when using complete medium for culture of cells; the specific activity of enzyme extracts produced by culture in complete medium was higher than that obtained in chemically-defined medium. 5-methylhydantoin was shown to be the preferred substrate for both the hydantoinase and carbamylase enzymes in the crude extract of RU-KM3L. The substrate specificity of the hydantoinase and carbamylase enzymes of the crude RU-KM3L extract was observed to be altered in the presence of increasing amounts of hydantoin, 5,5-dihydrouracil (DHU) and 5-thiouracil (TU) as inducers, showing selectivity for 5-methylhydantoin over hydantoin at inducer concentrations of 0.1 to 1%. A limiting effect on the hydrolysis of 5-methylhydantoin was observed when DHU and 5,5-dimethylhydantoin (DMH) were used as inducers, while the limiting effect on hydantoin specificity was observed when DHU and TU were used as inducers. The limiting effect was observed to be dependent upon the concentration of inducer, and was not observed when hydantoin was used as an inducer. The optimal time for assay of the hydantoinase enzyme in crude extract preparations at 50°C was observed to be 3h. Alkaline conditions were shown to be optimal for both the hydantoinase and carbamylase enzymes of RU-KM3L. Assay for enzyme activities of RU-KM3L extract in the presence of metal ions showed Mn²⁺ ions (and to a lesser extent, Co²⁺) to activate both the hydantoinase and carbamylase activities. Cu²⁺ ions were observed to inhibit the hydantoinase enzyme. In order to determine the location of the enzymes within the cell, cell debris from disrupted cells of RU-KM3L was removed by centrifugation. A decrease in enzyme activity in the supernatant was observed, and suggested association of the enzymes with the cell membrane. Ammonium sulfate fractionation experiments conducted on the crude extract provided further evidence for this result. Sonication of the crude enzyme extract was the only successful method for the releasing of membrane-associated enzyme. Of a number of strategies investigated, the use of sucrose at 50% (w/v) concentration was shown to preserve the hydantoinase and carbamylase enzyme activities during lyophilisation. Furthermore, assay for these enzyme activities showed the activities to be higher after lyophilisation in the presence of sucrose. However, sucrose did not increase the thermostability of lyophilised crude enzyme extracts. Water-miscible organic solvents at 1% concentration were shown to be inhibitory to the hydantoinase and carbamylase enzymes of RU-KM3L, and the inhibition was also observed to increase with increasing concentrations of these solvents. Hydantoinase activity in the presence of water-immiscible organic solvents was shown to increase with an increase in the hydrophobicity of these solvents, but the activity observed was not significantly higher than activity in the absence of solvent when hydantoin and 5-methylhydantoin were used as substrates. The possibility of reversing the hydantoinase enzyme reaction by water-immiscible organic solvents was investigated, and the results obtained suggested that the reaction could be reversed. It was thought that the partitioning of substrates or products into hydrophobic organic solvents could influence the reaction equilibrium, but the partitioning observed was not sufficient to affect reaction rates. Peptide synthesis was shown to have occurred in small amounts when the hydantoinase reaction was carried out in the presence of water-immiscible organic solvents. In conclusion, the hydantoin-hydrolyzing enzyme activity of a crude extract preparation from the bacterial strain RU-KM3L was characterised at elevated temperatures, and in the presence of watermiscible and -immiscible organic solvents.
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The legal position of unmarried fathers in the adoption process after Fraser v Children's Court, Pretoria North, and others 1997 (2) SA 261 (CC) : towards a constitutionally-sound adoption statute

  • Authors: Schäfer, Lawrence Ivan, 1972-
  • Date: 1999
  • Subjects: Unmarried fathers -- Legal status, laws, etc. -- South Africa , Unmarried fathers -- Legal status, laws, etc. -- Case studies , Children's rights -- South Africa , Adoption -- Law and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:3694 , http://hdl.handle.net/10962/d1003209 , Unmarried fathers -- Legal status, laws, etc. -- South Africa , Unmarried fathers -- Legal status, laws, etc. -- Case studies , Children's rights -- South Africa , Adoption -- Law and legislation -- South Africa
  • Description: The subject-matter of this thesis is the rule, previously contained in section 18(4)(d) of the Child Care Act 74 of 1983, in terms of which a mother could surrender her child born out of wedlock for adoption without the consent of its father. This section was struck down as unconstitutional by the Constitutional Court in Fraser v Children's Court, Pretoria North and others 1997 (2) SA 261 (CC), on the grounds that it violated an unmarried father’s constitutional rights to equality and non-discrimination. In the light of this judgment, this thesis seeks to articulate the constitutional parameters within which section 18(4)(d) must be amended. The requirements of Fraser are identified and discussed. Regard is also had to other constitutional rights upon which Fraser might have been decided; in particular, an unmarried father’s right to procedural fairness, and his child’s right to family or parental care. Case law from the United States, Canada, Ireland and the European Court of Human Rights is also discussed. The end product of this examination is an exposition of the various constitutional rights which vest in the father of a child born out of wedlock. A separate exposition is given of the distinct rights which vest in all children in the adoption process. The latter set of rights is drawn both from the Constitution of the Republic of South Africa Act 96 of 1996, and the United Nations Convention on the Rights of the Child. The thesis then proceeds to examine the Adoption Matters Amendment Act 56 of 1998, which was enacted in response to Fraser. The consent and notice provisions of adoption statutes in the United States, Canada, Australia, Ireland and England are also examined, and compared to the provisions of the Adoption Matters Amendment Act. The object, here, is two-fold: first, to consider the practical value of this Act; and second, to consider whether it satisfies the constitutional requirements identified earlier in this thesis. The thesis concludes with suggestions for the improvement of this Act.
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The market for commercial farm land in the Eastern Cape Province of South Africa as a means of redistribution:

  • Authors: Antrobus, Geoffrey G , Fraser, Gavin C G
  • Date: 1999
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/143024 , vital:38194 , DOI: 10.4314/rosas.v3i1.22991
  • Description: The election promise of the majority party in the new South African government was to redistribute 30% of the agricultural land in the hands of Whites within a period of 5 years. Transfers of land in the Eastern Cape Province are examined as a case study. While 60% of the total number of Eastern Cape farms changed hands over 5 years, these constituted only 19% of the surface area. A large proportion of rural transfers were small (less than 5 hectares) peri-urban properties which cannot all be considered as viable farming units. At average prices about R1 to R2 billion would be required to establish new farmers on land with the necessary livestock, machinery and equipment. Resource poor new entrants would need a major state contribution to make initial entry and subsequent survival feasible. To achieve their goal through market transfers the government would need to either substantially lengthen its time horizon or lower its target.
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The power behind the scenes: the Afrikaner Nationalist Women's Parties, 1915 to 1931.

  • Authors: Vincent, Louise
  • Date: 1999
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141795 , vital:38005 , DOI: 10.1080/02582479908671348
  • Description: The Enlightenment expectation was that political identity based on ethnic nationalist sentiments would gradually give way to more ‘rational’ forms of association. That expectation has, in the late twentieth century, proved somewhat premature. The explosion of ethnic nationalist conflicts onto the international stage in the post-Cold War era has brought with it a renewed intellectual interest in the politics of nationalism and ethnicity. In response to the need for new avenues of inquiry amidst a vast and growing literature, Anthony Smith’s work on national identity appeals for a research agenda which treats nations and nationalism as cultural phenomena as well as forms of politics.
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The process of learning and teaching in supplemental instruction groups at Rhodes University

  • Authors: Vorster, Jo-Anne Elizabeth
  • Date: 1999
  • Subjects: Group work in education , Team learning approach in education , College teaching -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3081 , http://hdl.handle.net/10962/d1002590 , Group work in education , Team learning approach in education , College teaching -- South Africa
  • Description: This thesis investigates the process of peer collaborative learning in three Supplemental Instruction (SI) groups at Rhodes University. The roles of the SI leader, the students and the task in the peer-collaborative learning-teaching process were researched. The research is rooted in sociocultural theories of learning and development. The notion of activity is thus central to this investigation. The tasks, goals and interactions in the SI sessions were analysed in order to arrive at an understanding of the process of learning-teaching in each of the three SI sessions. A method of analysis devised by Van Vlaenderen to study the process of everyday cognition in the problem solving activities of community activists (1997) was adapted for this study. The method of analysis was used to study the interaction processes of participants in the SI groups. Each interaction between the SI participants was broken into its constituent parts and labeled in terms of the goals of the interactions in relation to the preceding interaction or operation, the task or subtask under discussion, and the SI session as a whole. Data from the analysis of the activity were quantified in order to assess the quality of the learning-teaching process. A qualitative analysis of the patterns of mediation was used in conjunction with the quantified data of interaction patterns to draw conclusions about the nature of the peer collaborative learning-teaching process in the three SI sessions. The research findings indicate that the nature of the SI task is crucial; students in SI need to be able and willing to participate; and the facilitation style of the SI leader plays a role in determining the quality of the activity in the SI session. The thesis explicates learning-teaching activity that results in higher order learning.
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The psychological adjustment of middle managers after revolutionary organisational change

  • Authors: Coates, Nicholas Robert
  • Date: 1999
  • Subjects: Psychology, Industrial -- South Africa Organizational change -- South Africa Organizational change -- Psychological aspects Management -- Psychological aspects
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3190 , http://hdl.handle.net/10962/d1008554
  • Description: With the accelerated process of political and socio-economic transformation in South Africa, revolutionary organisational change has become a given in contemporary South African business life (Human & Horwitz, 1992). For revolutionary organisational change to succeed in South Africa, middle managers who represent the 'cement' of the organisation, need to adjust at the individual level. However, the literature on organisational change remains curiously silent about individual adjustment (Ashford, 1988). The goals of the research were firstly, to recount the middle manager's perceptions and experiences of revolutionary organisational change. Secondly, to detail the psychological re-
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The relative influence of value priorities ethnicity and worries in the determination of political party affiliation amongst Ugandan university students

  • Authors: Kibanja, Grace M
  • Date: 1999
  • Subjects: Political psychology , Uganda -- Politics and government -- 1979- , Students -- Uganda -- Political activity , College students -- Uganda -- Psychology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3003 , http://hdl.handle.net/10962/d1002512 , Political psychology , Uganda -- Politics and government -- 1979- , Students -- Uganda -- Political activity , College students -- Uganda -- Psychology
  • Description: This study examines the relative influence of value priorities, ethnicity and 'worries' in the determination of political party affiliation amongst Ugandan university students. Schwartz's values questionnaire was administered to 309 male and 176 female first year students from the faculties of engineering, medicine, law, commerce, social sciences, sciences, education and mass communication at Makerere University Uganda. The sample included respondents from all of the six sub-ethnic groups in Uganda. Respondents also covered the major religious groups in the country and were also representative of the major political parties. Results from the statistical analysis on the data show that ethnicity and certain values playa role in the determination of these students' affiliation to a political party. Chi-square results show that achievement, benevolence, universalism, security, tradition and conformity values are given differing importance across political parties. And, Anova results show that the tradition value has a significant mean difference across parties. Other factors such as religion and course of study are also found to have significant influence on these student's affiliation to political parties. Although 'worries' are found not to have a significant influence on student's political party affiliation, findings show that students from different political parties differ in their ratings of the different types of ' worries'. Therefore results show that ethnicity and value priorities do infl4ence these students' affiliation to a political party but ' worries' do not. The discussion section explores these findings in the context of contemporary Ugandan politics.
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The removal of toxic heavy metals from aqueous solutions by algal extracellular polysaccharides

  • Authors: Selepe, Mamaropeng Marcus
  • Date: 1999
  • Subjects: Heavy metals -- Absorption and adsorption , Copper , Lead , Algae -- Biotechnology , Polysaccharides -- Biotechnology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3994 , http://hdl.handle.net/10962/d1004054 , Heavy metals -- Absorption and adsorption , Copper , Lead , Algae -- Biotechnology , Polysaccharides -- Biotechnology
  • Description: This study investigated the possible use of algal extracellular polysaccharide as a biosorbent for removal of heavy metals (copper and lead) from aqueous solutions as a means of bioremediation for metal containing effluents. This biopolymer has good biosorbent properties and a potential to provide a cost effective, selective and efficient purification system. A variety of environmental conditions induce the production of extracellular polysaccharides in algae. The production of exopolysaccharides by Dunaliella cultures was induced by nitrogen deficient conditions. A high ratio of carbon to nitrogen source considerably enhanced the polysaccharide release. Purified extracellular polysaccharide samples exhibited a monosaccharide composition consisting of the following sugars: xylose, arabinose, 2-0-methyl mannose, mannose, glucose and galactose. The relative abundance (%) of these sugars were calculated relative to xylose. The major sugar constituent was 2-0-methyl mannose, which was present at approximately 160% relative to xylose. The percentage relative abundance of other sugars was as follows: 18.8; 86.8; 85.3 and 22.3% for arabinose; mannose; glucose and galactose respectively. The identity of the various constituents were confirmed by mass spectrometry. The ability of Dunaliella exopolysaccharides to accumulate metals was investigated. The following parameters were studied because they affect metal uptake: solution pH, biomass concentration, temperature, time and metal concentration. The uptake of both copper and lead were pH dependent. However, metal uptake was not significantly affected by temperature. Kinetic studies showed that Dunaliella extracellular polysaccharides exhibit good bioremediation properties. Metal uptake was rapid. In addition, the exopolysaccharide has good metal binding capacity with an uptake capacity for lead of 80 mg/g from a solution containing initial lead concentration of approximately 40 mg/l. Competition studies revealed that the presence of a second metal in solution inhibits uptake of the other metal compared to uptake in single metal solution of that particular metal. The presence of lead inhibited the uptake of copper from approximately 65% in single metal solution to 10% in binary metal solution. The presence of copper also inhibited lead uptake, though not to the same extent. Higher concentrations of lead could not completely prevent removal of copper from solution and visa versa. The same was true for lead which could not be displaced by a four-fold concentration of copper. Instead, a certain percentage of copper was always removed showing that lead did not compete with copper for these binding sites. In conclusion it appears that, copper and lead bind to different sites on Dunaliella exopolysaccharides and that they exhibit selective or preferential removal of lead.
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The role of indigenous knowledge in/for environmental education: the case of a Nguni story in the Schools Water Action Project

  • Authors: Masuku, Lynette Sibongile
  • Date: 1999
  • Subjects: Environmental education Environmental education -- South Africa -- KwaZulu-Natal
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1749 , http://hdl.handle.net/10962/d1003633
  • Description: In March 1997 an indigenous knowledge story was included by the Schools Water Action Project (SWAP)partners in a resource pack for Water Week educational activities. This research developed as the result of an interaction between myself and some of the schools while we investigated water quality within Howick in the KwaZulu Natal Midlands. An interest in understanding the role of indigenous knowledge in/for environmental education developed. Some of the teachers and students involved in the water audit were requested to share their views on the role of indigenous knowledge in/for environmental education. From here the study broadened to also include interviews with elderly community members and environmental educators involved in materials development processes. This post-positivistic case study documents the views of a small sample of interviewees using the SWAP story entitled Sweet Water as a spring board towards a better understanding of indigenous knowledge within the school context, with a particular aim to inform educational materials development processes. The study displayed that a link which exists between indigenous knowledge and environmental education needs to be brought to the fore. This is likely to happen with the blurring of boundaries between home and school as learning contexts, a process which student interviewees emphasised, along with the need for respecting values that award respect to the environment. Elderly community members were of the view that they have a role to play in addressing educational problems such as interpersonal and intercultural respect. However, the study also raised several issues around the complexities surrounding indigenous knowledge processes, including its appropriation, commodification and reification.
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The role of vitamin E succinate in regulation of growth and cyclooxygenase expression in B16 murine melanoma cells

  • Authors: Van der Merwe, Adele Shanette
  • Date: 1999
  • Subjects: Melanoma , Vitamin E
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3988 , http://hdl.handle.net/10962/d1004047 , Melanoma , Vitamin E
  • Description: This study was undertaken to determine the effects and possible mechanism of action of vitamin E succinate supplementation on B16 murine melanoma cell growth in vitro. Studies revealed that supplementation of 5, 7 and 10µg/ml of this vitamin significantly inhibited growth of B16 cells. Non-malignant LLCMK cells supplemented with the same concentrations of vitamin E succinate resulted in similar inhibition of cell growth. The actual mechanism by which vitamin E succinate inhibits B16 cell growth is unclear, though there has been much speculation about its possible role as an antioxidant. Vitamin E succinate is not a physiological antioxidant and for this ester to behave as an antioxidant, cleavage of the ester bond must occur, releasing the antioxidant vitamin E part of the molecule. To determine whether the observed inhibitory effects on B16 cell growth were due to the intact vitamin E succinate or the vitamin E cleavage product, cleavage studies were undertaken. Results from these studies revealed that in B16 cells vitamin E succinate cleavage did not occur suggesting that the observed inhibitory effects of vitamin E succinate on B16 cells were due to the intact compound. In contrast vitamin E succinate cleavage was shown to occur in LLCMK cells, suggesting that these cells may contain an esterase capable of liberating succinic acid and vitamin E. Further studies focussed on the possible role of vitamin E succinate in regulation of cyclooxygenase activity in B16 cells as vitamin E succinate was found to effect the activity of various enzymes involved in the arachidonic acid cascade, notably cyclooxygenase, the rate-limiting enzyme in prostaglandin synthesis. Time course studies were used to determine when the cyclooxygenase protein was being produced, thus allowing an estimation of when the gene was being 'switched on'. These studies revealed that vitamin E succinate does not significantly effect cyclooxygenase activity in B16 cells over a period of 2 to 12 hours as compared to the OE control cultures. Further studies using RNA techniques investigated whether vitamin E succinate was having an effect on cyclooxygenase activity at a molecular level. These investigations were unsuccessful for the 6 day supplementation for a number of possible reasons, the main reason being RNA stability. Subsequent studies revealed an increase in COX mRNA after 2 hours, suggesting that the gene was 'switched on' soon after supplementation with vitamin E succinate, and further increases in COX mRNA were observed after 8 to 12 hours. The molecular studies were, however, inconclusive. Previous studies suggested that vitamin E succinate was indirectly causing growth inhibition of B16 cells via regulation of cyclooxygenase activity, however, this study does not support these findings and it would seem unlikely that regulation of cyclooxygenase expression in B16 cells by vitamin E succinate has a role to play in the mechanism by which vitamin E succinate inhibits growth in B16 cells.
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The social construction of 'capacity building': a grounded theory study of organisation development consultants' accounts

  • Authors: Eagar, Ryan
  • Date: 1999
  • Subjects: Organizational change -- South Africa , Business consultants -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:2969 , http://hdl.handle.net/10962/d1002478 , Organizational change -- South Africa , Business consultants -- South Africa
  • Description: The primary aim of this thesis is to explore, through organisation development (OD) consultants' accounts, the meaning of 'capacity building' in the South African development context. The need for theory development in this area is apparent from two interrelated vantage points. Firstly, while 'capacity building' is an increasingly espoused development approach, it is seen to be a confusing and ill-defined concept, for which there exists no adequate theory. Secondly, there is an growing call within the OD field to perfonn 'recOIlllaissance' (Weick,1990) on OD as it is being practised in different socio-historical and organisational contexts, so as to discern future trends for this discipline. Due to the lack of documented debate which grounds OD issues in the South African development sector, OD practitioners' 'capacity building' interventions were seen to provide suitably unchartered terrain for this study. Given that theory generation was intended, the general epistemological principles provided by Glaser and Strauss's (1967) 'grounded theory' methodology were adopted. As a way of avoiding some of the criticisms and limitations of this approach, this thesis followed later conceptualisations of this method, in particular its reframing within the social constructionist idiom. In accordance with this perspective, this study directed attention to the ways in which OD consultants, in a non-governmental organisational (NGO) sector known as 'intermediary' NGOs, accounted for their 'capacity building' role in this development context. The results, based on in-depth interviews with ten OD consultants, indicate that 'capacity building' is an elusive and inchoate concept with more than one meaning for the participants. Their narrative account variously constructs 'capacity building' as value-driven OD process facilitation; funder and market regulated service provision; and people-driven product delivery. As a result of this multi-vocal construction, the participants' accounts reveal that OD consultancy in this sector is primarily concerned with 'managing the tensions' of the consultants' ambiguous and contradictory roles. By examining how the tensions articulated by the consultants inhere in their relationship to the environment in which they operate, this thesis firstly explores how the contradiction and anlbiguity attached to this concept can be traced to different stakeholder expectations of 'capacity building'. Secondly, it exanlines how these different stakeholder discourses conflict with each other and with an OD perspective. Thirdly, through an explication of the core category of 'managing tensions', it explores the image of OD consulting as a 'shifting and inconstant balancing act'. Fourthly, it shows how there exist wider contextual forces operating in the development sector which serve to throw these consultants 'off balance' and into delimited and 'received' service provision roles which run counter to their raison d'etre. Finally, the research examines new ways of approaching the 'capacity building' question and of understanding the nature of OD consultancy. It concludes with an attempt to respond to a conceptual aporia in OD literature by examining possible alternative images and metaphors for the role of the OD consultant.
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The use of investigative methods in teaching and learning primary mathematics in Lebowa schools : a case study

  • Authors: Sebela, Mokgoko Petrus
  • Date: 1999
  • Subjects: Mathematics -- Study and teaching (Primary) -- South Africa -- Northern Province -- Case studies Mathematics -- Study and teaching (Primary) -- South Africa -- Northern Province
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1814 , http://hdl.handle.net/10962/d1003700
  • Description: This is a report on research conducted in Lebowa (Northern Province) Primary Mathematics Project schools. In view of the high failure rate of matric students, the researcher believes that it is necessary that ways should be devised to improve mathematics understanding from the first level of schooling. A research study was made of constructivist and investigative teaching and learning methods as employed by teachers in a number of primary schools in the area. The researcher believes that investigative and constructivist teaching approaches produce better results than the traditional approach. He further believes that children learn better in a co-operative non-threatening classroom environment. A pilot study was made with two experimental schools and two control schools. The schools were selected from both urban and rural areas. The experimental schools are operating under the PMP and the control schools are not. The experimental schools are also supported by expert teachers called key teachers. Many of these key teachers have attended courses at Leeds University, while others have been trained locally in the theory and practice of constructivist and investigative teaching and learning. Chapter 3 illustrates clearly what is done in the Project schools. The methodology employed in the research included qUestionnaire responses from 174 teachers. Written tests by four schools (350 pupils), and interviews with 55 people, including directors of education, inspectors, principals, teachers and parents. Observations in classes were also done. Another questionnaire was given to 484 pupils. The tests were mitten on two occasions: an initial test was written during November 1993, the second year of the PMP project, while a second test was written the following year. Data collected was analysed and positive results obtained. The results from the tests indicated that pupils in experimental schools where constructivist and investigative approaches are used, perform better than those from schools where the traditional approach is still used. They indicated that children in PMP schools develop a better understanding of mathematics. This would seem to indicate that the constructivist and investigative approach to teaching produces better results than the traditional approaches. The reader will find graphs indicating the results and their analysis in Chapters 4 and 5. It is recommended by the researcher that: - Constructivist and investigative teaching and learning methods be introduced to all schools. - The services of key teachers be supported by the Department - The Department should equip all schools with the necessary materials for proper teaching and learning, or provide materials for schools to make their own teaching aids. - Teachers be involved with materials production where they are given guidance on how teaching aids can be made. - The curriculum for primary school mathematics be revised and changed, especially in view of the fact that at present it does not cater for local needs. It was planned by whites and it caters mainly for those with an European cultural background.
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The Virtual Remote Control-An Extensible, Virtual Reality, User Interface Device

  • Authors: Rorke, Michael , Bangay, Shaun D
  • Date: 1999
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/432743 , vital:72896 , https://www.cs.ru.ac.za/research/Groups/vrsig/pastprojects/013interaction/paper02.pdf
  • Description: Immersive virtual reality (VR) places the user inside of the computing envi-ronment, blurring the distinction between the environment itself and the user interface to access that environment non-obvious. This lack of distinction between environment and interface makes it difficult to place menus and other interface elements where the user is both able to access them easily and where they do not obscure large parts of the users field of view. We propose a system called the 'Virtual Remote Control' (VRC). The VRC con-sists of a physical device (a small touchpad tracked using a Polhemus In-sideTrak magnetic tracker) which the user is able to hold and for which there is a representation in the virtual environment. The VRC is represented in the environment by a virtual menu. The user is able to make selections from the virtual menu by moving their finger around the touch pad part of the VRC and 'tapping' on the required action. Additionally, the user is able to select an object for the action to be applied on, by 'pointing' the representa-tion of the VRC at the object-as one would point a remote control at a Hi-fi of TV set.
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The Winter's Tale shaping our own Renaissance. A play for the 21st Century

  • Authors: Wright, Laurence
  • Date: 1999
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/455874 , vital:75464 , https://hdl.handle.net/10520/AJA1011582X_198
  • Description: The Winters Tale is an extraordinarily elusive play. My contention in this paper" is that, just as Hamlet became the Shakespearean drama for the nineteenth century, and King Lear spoke deeply to the twentieth centu-ry, so it may well be that The Winters Tale will take centre stage for the new millennium. We used to know what the play was about in an easy, non-problematic fashion. It was about repentance and reconciliation; it was about the cycle of the seasons; it was about the Pandosto sub-title,“The Triumph of Time"; later, it became a tricksy celebration of con-tention between Art and Nature (despite the considerable discomfort inflicted upon the dramatis personae), an experiment in the new genre of tragicomedy, or a glittering theatrical tour de force–a romance, but heartless and rather empty. I would maintain that beneath all such read-ings is the assumption that the play is really “a winter's tale': a some-what inconsequential yarn suitable for whiling away a cold evening round the fireside, a view often infused with some lingering taint of the Edwardian view that Shakespeare had “gone sloppy” in his technique."
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Thermoregulatory capabilities of the woodland dormouse, Graphiurus murinus

  • Authors: Whittington-Jones, Craig A , Brown, C R
  • Date: 1999
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/447349 , vital:74613 , https://doi.org/10.1080/02541858.1999.11448485
  • Description: The woodland dormouse, Graphiurus murinus, in common with many other small rodents, enters torpor under conditions of food deprivation and low temperatures. Its thermoregulatory capabilities under more favourable conditions, however, have not been investigated. We measured metabolism and thermoregulation in woodland dormice acclimated to long-day length, moderate temperature and abundant food over a temperature range (Ta) of approximately 5–37°C. The thermal neutral zone for this species lay between 29 and 35°C. Estimated resting metabolic rate (RMR) within this range averaged 21.10 ± 3.28 J g-1 h-1.
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