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WCED causes crisis in education

  • Authors: SADTU
  • Date: 1997
  • Subjects: SADTU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/162052 , vital:40752
  • Description: On 15 December 1997 the WCED tabled a proposal in the ELRC. This would effectively terminate the contracts of 3333 temporary educators who were filling vacant substantive posts that were created after 1 July 1996 as a result of the rationalisation process. Not only will temporary educators be dismissed, but the posts that they occupy will be frozen. This means that the teachers who remain behind at schools will have increased workloads and will have to manage bigger class sizes
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  • Date Issued: 1997

Voltammetric behavior of cysteine and metallothionein on cobalt (II) tetrasulfonated phthalocyanine modified glassy carbon electrodes

  • Authors: Limson, Janice L , Nyokong, Tebello
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293346 , vital:57077 , xlink:href="https://doi.org/10.1002/elan.1140090314"
  • Description: Cysteine, and rat Cd, Zn-metallothionein (Cd, Zn-MT) have been studied electrochemically at glassy carbon electrodes modified with cobalt(II) tetrasulfonated phthalocyanine, [CoIITSPc]4−, where Pc(2-) = phthalocyanine dianion. The electrode was modified by electrodeposition of [CoIITSPc]4−. The anodic currents for the oxidation of cysteine on these electrodes are observed at 0.82 V (vs. Ag/AgCl) in acidic media. The anodic currents for the oxidation of Cd, Zn-MT are observed at 0.90 V at pH 8.4 (Tris buffer).
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  • Date Issued: 1997

Vitamin E supplementation and secondary metabolites interactions and effects on melanoma growth

  • Authors: Ottino, Paulo
  • Date: 1997
  • Subjects: Vitamin E Melanoma
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4016 , http://hdl.handle.net/10962/d1004076
  • Description: The present study was undertaken to determine the effects and possible mechanism of action of vitamin E succinate on malignant murine melanoma (BL6) and non-malignant monkey kidney (LLCMK) cell growth in vitro. Studies revealed that supplementation of 5, 7 and lOJLg/ml vitamin E succinate significantly inhibited BL6 cell growth, while in LLCMK cells no significant increase or decrease in growth was observed. The actual mechanism by which vitamin E succinate inhibits BL6 cell growth is at present unclear. Studies have suggested a radical or oxidant involvement in a number of degenerative diseases such as cancer, and that supplementation of antioxidant vitamins such as vitamin E may function to reduce cancer cell growth by quenching free radical species and preventing lipid peroxidation. In addition to its antioxidant role in a cell, vitamin E is believed to modulate the activities of various enzymes and metabolites in the eicosanoid pathway. Hence, this study investigated the effects of vitamin E succinate supplementation on free radical and lipid peroxidation levels, as well as the activities of various enzymes and metabolites ill the eicosanoid pathway. Throughout this study, emphasis was placed on BL6 melanoma cells since the magnitude of the relationship between LLCMK growth and the levels of various enzymes and metabolites in the eicosanoid pathway varied considerably from one experiment to another and did not show the consistent trend found with the BL6 cells. A decrease in cell growth was found to be accompanied by a concomitant increase rather than a decrease in the levels of free radicals and lipid peroxidation, suggesting that the growth inhibitory effects of vitamin E succinate on BL6 cells in vitro was not due to its antioxidant properties associated with the vitamin E component, but rather due to one or more of its other potential roles within the cell. This proposal was further strengthened by findings that vitamin E succinate, a non-physiological antioxidant in its esterified form, did not undergo significant cleavage to free vitamin E in the BL6 cells. Vitamin E succinate is believed to modulate membrane bound enzyme activities through physicochemical interactions with membrane lipids and changes in membrane fluidity. Hence, this study investigated the role of vitamin E succinate in modulating the activity of various enzymes and secondary messengers in the eicosanoid pathway. Supplementation of l-lOjLg/ml vitamin E succinate resulted in an overall increase in phospholipase A2 activity while cyclooxygenase and adenyl ate cyclase activities were found to be significantly increased at vitamin E succinate concentrations of 7 and WjLg/ml respectively. A significant increase in" 5-LOX activity was observed a! 10jLg/mi supplementation. The suggestion that vitamin E succinate modulates membrane bound enzyme activities was further strengthened by uptake and cellular distribution studies, which showed significantly higher levels of vitamin E succinate in membrane fractions of BL6 cells when compared with stroma fractions. Another factor which could account for elevated PLA2,-5-LOX and COX activities in BL6 cells as a result of vitamin E succinate supplementation, was that of intracellular calcium levels. Supplementation of BL6 cells with 1-7 jLg/ml vitamin E succinate resulted in an overall increase in intracellular calcium levels. These changes in calcium levels however were positively correlated with changes in PLA2 activity only. Since the rate of prostaglandin synthesis is controlled by phospholipase A2 activity, and net prostagiandin production is dependant on cyclooxygenase activity, the effects of vitamin E succinate supplementation on prostaglandin levels in BL6 cells was determined. Vitamin E succinate supplementation resulted in a significant decrease in prostaglandin D2 levels at vitamin E succinate concentrations of 3, 5, 7 and lOjLg/ml respectively, while prostaglandin F2a levels were significantly decreased at 1-10jLg/ml vitamin E succinate. The increases in prostaglandin E2 and 12 levels were inversely related to BL6 cell growth suggesting that both prostaglandins may act as negative regulators of BL6 cell growth. When comparing prostaglandin E2 levels to prostaglandin 12 levels in BL6 cells, significantly higher levels of prostaglandin E2 were found, suggesting that vitamin E succinate effects were mediated primarily through an increase in prostaglandin E2 levels. Furthermore, prostaglandin E2 levels are believed to modulate adenylate cyclase activity. It is therefore reasonable to conclude that the increased adenyl ate cyclase activity found in BL6 cells was dependant on prostaglandin E2 levels, since increases in prostaglandin E2 levels at 7 and lOjLg/ml vitamin E succinate correlated with an increase in adenylate cyclase activity and cyclic adenosine monophosphate levels. Thus it appeared that the observed inhibitory effects of vitamin E succinate supplementation on BL6 cell growth was not due to the antioxidant properties associated with the vitamin E component of the vitamin E succinate molecule, but was rather mediated in part through a cascade effect initiated by phospholipase A2 activation and archidonic acid release. This initial effect then appeared to result in an increase in cyclooxygenase activity and activation of a prostaglandin E2-adenylate cyclase-cyclic adenosine monophosphate linked system, ultimately altering cyclic adenosine monophosphate levels and inhibiting BL6 cell growth. This was confirmed when BL6 cells were supplemented with indomethacin, a cyclooxygenase inhibitor. Supplementation with the inhibitor resulted in vitamin E succinate having no inhibitory effects on BL6 cell growth. Furthermore, when comparing the levels of prostaglandin ~, adenylate cyclase activity and cyclIC adenosine monophosphate in the indomethacin treated cultures to non-indomethacin treated cultures, markedly lower levels of these metabolites were found in the indomethacin treated cultures. The cause of the increase in free radical and lipid peroxidation levels in BL6 cells following vitamin E succinate supplementation was further investigated. Cyclooxygenase enzymes are believed to generate free radical species and contribute to lipid peroxidation levels during catalytic activity. Markedly lower levels of free radicals and lipid peroxidation in indomethacin treated cultures were found when compared with vitamin E succinate treated cultures alone, suggesting that the increases in free radical and lipid peroxidation levels in BL6 cells supplemented with vitamin E succinate were indirectly due to an increase in cyclooxygenase activity in these cells.
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  • Date Issued: 1997

Variation in foraging activity of Acanthochitona garnoti (Mollusca: Polyplacophora) from different habitats

  • Authors: Cretchley, Robyn , Hodgson, Alan N , Gray David R , Reddy, Kasturi
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/447642 , vital:74663 , https://www.ajol.info/index.php/az/article/view/154647
  • Description: Activity of Acanthochitona garno {i was studied on an exposed horizon-tal platform of aeolian sandstone (I (enton-on-Sea-33'41'S; 26'40'E) and a quartzitic sandstone boulder shore (Cannon Rocks-33 44'S; 26'35'E), during 1994. In addition, the activity rhythms of chitons which were permanent inhabitants of high sbore rock pools at Kenton-on Sea were observed. All sites experienced semi-diurnal tides, the tidal range being about 1.9 m on mean spring tides. and 0.9 m on mean neap tides, with highest spring tides phased around.
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  • Date Issued: 1997

Use of cobalt (II) phthalocyanine to improve the sensitivity and stability of glassy carbon electrodes for the detection of cresols, chlorophenols and phenol

  • Authors: Mafatle, Tsukutlane J , Nyokong, Tebello
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293335 , vital:57076 , xlink:href="https://doi.org/10.1016/S0003-2670(97)00464-9"
  • Description: A cobalt(II) phthalocyanine-modified glassy carbon electrode (CoPc-GCE) was used for the detection of o-, m- and p-cresols, and of 2-chlorophenol, 4-chlorophenol and phenol. Modification of the glassy carbon electrode with CoPc increases the oxidation currents of these species and increases the stability of the electrode. CoPc-GCE showed less fouling by the oxidation products of these compounds than the unmodified GCE. Comparison of some first row transition metal phthalocyanines showed the following trend for the enhancement of the currents for the oxidation of cresols and phenols: Co(II)Pc > Mn(II)Pc > Fe(II)Pc > Ni(II)Pc > Cu(II)Pc > H2Pc > Zn(II)Pc > GCE. When [Co(II)TSPc]4− (TSPc=tetrasulfo Pc) was added to aqueous solutions containing the cresols and phenols, an enhancement of the oxidation currents was also observed.
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  • Date Issued: 1997

Urban agriculture: advocacy and practice: a discursive study with particular reference to three Eastern Cape centres

  • Authors: Webb, Nigel Leigh
  • Date: 1997
  • Subjects: Urban agriculture -- South Africa -- Eastern Cape Land use, Urban -- South Africa -- Eastern Cape Agriculture -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2095 , http://hdl.handle.net/10962/d1002658
  • Description: The purpose of this thesis is to explain the continued advocacy of 'urban agriculture' (UA) in the literature in the face of the seemingly modest role played by cultivation in practice. The analytical framework adopted isrthat of discourse, the theoretical underpinnings of which are derived from the early works of Foucault, and applications such as those of Escobar (1989; 1991) and Ferguson (1990). Using a discursive orientation involves two main tasks - an explanation of how 'UA' has gained some prominence and the man~er in which its currency is able to be maintained. The investigation included an in-depth analysis of the literature and empirical research in th!"e~Eastern Cape centres. The function of the empirical findings is to expose the discourse, as well as to extend the empirical base relating to 'urban agricultural' research in general. The thesis suggests that the growth in interest in 'UA' is a result of a Foucaultian "gap" opening in the discourse. Changes in the conceptualisation of development, the rise-in prominence of the urban poor and emerging ecodevelopment views, among others, have given proponents of "UA' greater room for manoeuvre. However, most case studies promote 'UA' despite providing little evidence of its role in household welfare. The way the discourse maintains its' currency is in the manner in which the objects of 'UA' are constituted. Firstly, the people are characterised as poor, largely divorced from their rural origins, and mainly female. Each of these assertions is questioned on the basis of the literature itself and the empirical findings. Secondly, in the practice of cultivation, emphasis is placed on the inputs used, and the crops that are produced. The treatment of both the inputs and the crops by the literature is cursory. Investigations show that land availability, garden size and irrigation water are e~pecially problematic and vegetable consumption remains low. Four types of alleged benefit associated with 'UA' are analysed - environmental and ecological, psychological and social, financial, and nutritional. In each case commonly held assumptions are undermined by closer investigation. Thus, the thesis contends that the role played by cultivation is a modest one. Most of the claims made on behalf of 'UA' are more congruent with development discourse than actual cultivation practice.
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  • Date Issued: 1997

Umusango gwabalere

Umngqokolo

Ukwenda kuyahonjelwa

Troubled waters in south-western New Georgia, Solomon Islands: Is codification of the commons a viable avenue for resource use regularisation

  • Authors: Shankar, Aswani
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/440061 , vital:73732
  • Description: In recent decades there has been a growing interest in indigenous sea tenure institutions and their possible role in establishing a framework for sustainable resource use and conservation. Yet the feasibility of these institutions to cope with social and economic changes have been seldom explored. In this paper a case study is presented where internal deregularisation of the ‘commons’ is the result of existing socio-cultural principles combined with outside influences. Two territorial models are compared to elucidate emerging internal instabilities of sea tenure institutions and possible ways to correct existing problems. The codification of the commons is suggested here as a possible measure to strengthen indigenous common property regimes.
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  • Date Issued: 1997

Towards sustainable conversation: Developing environmental education processes

  • Authors: Le Roux, Kim
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/389884 , vital:68492 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/137446"
  • Description: This paper highlights the importance of seeing environmental education as a process and considers the value of conversation and storytelling in environmental education processes. These processes are explored from a post-structural perspective within the context of the writer's own involvement in supporting environmental education processes.
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  • Date Issued: 1997

Towards an understanding of Amayeza esiXhosa stores (African chemists): how they operate, and the services they offer in the Eastern Cape

  • Authors: Cocks, Michelle L
  • Date: 1997
  • Subjects: Medical anthropology -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:2096 , http://hdl.handle.net/10962/d1002659 , Medical anthropology -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
  • Description: In medical anthropology there has been a tendency to dichotomize western biomedical . healtb services, on the one hand, and traditional health care practices on the other. Much attention has been focused on the comparison between these two approaches in the hope that they might be reconciled. The problem with this approach is twofold. In the first place, it has not always acknowledged the local, historic~1, political and economic contexts in which different approaches to health care have evolved and in the second place, health care services which belong to neither the western nor traditional healing spheres and which are driven by commercial interests have been almost completely neglected because they fall outside of the basic dichotomy. Amayeza stores have been a feature of South African towns and cities for many years. They mayor may not be run by Africans, but their clientele is almost exclusively African in this region. They deal in a bewildering variety of products and remedies, from untreated herbal and animal products to pharmaceuticals specially prepared for the African market, to Dutch and Indian Remedies. These stores both reflect transfonnations in indigenous perceptions of health care and, by virtue of the choices they offer, generate change. In this empirical study three stores in the Eastern Cape are selected for detailed study - two in King William's Town, the regional capital, and one in the small town of Peddie. The approach is holistic, emphasizing the social, political and economic context, the business histories and running of each shop, and, in particular, the perceptions and choices of a sample of the customers in each case. The success of the amayeza phenomenon derives from its eclecticism and syncretism. These stores impose neither a western nor a traditional model of health care on their clients, but offer them a range of choices that reflects the complex multicultural history of their own South African society.
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  • Date Issued: 1997

Towards a developed regional order: which way forward southern Africa?

  • Authors: Blaauw, Abraham Lesley
  • Date: 1997
  • Subjects: Common Market for Eastern and Southern Africa , Regional planning -- Africa, Southern , Regional planning -- South Africa , Southern African Customs Union , Southern African Development Community , Africa, Southern -- Economic conditions , Africa, Southern -- Politics and government -- 1975-1994
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2760 , http://hdl.handle.net/10962/d1002970 , Common Market for Eastern and Southern Africa , Regional planning -- Africa, Southern , Regional planning -- South Africa , Southern African Customs Union , Southern African Development Community , Africa, Southern -- Economic conditions , Africa, Southern -- Politics and government -- 1975-1994
  • Description: The regionalisation of politics on a global scale, Call be seen as one of the defining features of contemporary international relations. Given this phenomenon, the tasks which confronted this thesis, was to consider the conditions and requirements necessary within the Southern African region to build an all-embracing developed regional order. The urgency with which the latter task should be undertaken, is premised on an increased realisation that the region, and indeed the continent as a whole, are becoming of lesser significance in international affairs. However, a number of impediments will have to be overcome, before the goal of a developed regional order can be achieved, which will contribute to lasting security in the region. Foremost amongst many issues, is how to employ the approaches to integration, in attempting to explain how the goal of a developed order should be achieved. A second problem which this thesis was confronted with, relates to which organisation shoulO be' considered the best vehicle, to drive the integration process forward- COMESA, SACU or SADC. The decision take SADC as the organisation to drive the integration process forward, is premised on a number of factors. Amongst many, it qualifies in geographical terms as a region, the historical linkages of the countries of the region (based on their fight against apartheid, division of labour, etc.), serves as a basis for building a sense of community. Thirdly its institutions can be developed to achieve the goal of an all-embracing regional order. Lastly and most importantly, SADC realises that regional integration will remain unattainable without the involvement of the peoples of Southern Africa. The identification of the organisation to drive the integration process forward, serves to bolster moves towards a maximalist order. However, significant changes in the structure and institutions of SADC is necessary, before it can be considered an all-embracing and developed regional order. Not suprisingly, therefore, we have witness a number of institutional changes to the SADC structures. Amongst many, the establishment of the Organ on Politics, Defence and Security , the signing of the SADC Trade Facilitation Protocol, and the commitment to democracy and a human rights culture, are most significant and will, it is hoped, provide the building-blocks for deeper integration in Southern Africa. Apart from the above, which occur between and among the states of the region, steps are underway between and among the agents of civil society to work closely with each other, to establish a regional civil society. Most notably, the establishment of a media society for Southern Africa, the calls by COSATU for a Social Charter with a regional flavour, the establishment of environmental and human rights networks, and the support for the Gay and Lesbian Movement of Zimbabwe (GALZ), represent landmarks, in the search for a developed regional order. However, the reluctance of the governments of the Southern African countries, to consult with the NGOs, before the adoption of the Organ Politics, clearly bears testimony to their present inability to take the necessary steps needed to move from a minimalist to a maximalist conception of regional organisation. The suggestion of this thesis is that the move-away from minimalism to maximalism can be facilitated by the development of a political centre-around which both governments and NGO activities can be articulated, since both are primarily concerned with the security and welfare of the Southern African region.
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  • Date Issued: 1997

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