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Maguqela lendawo

- Group performance, Group composition, Dargie, Dave

Management education and training

- Amos, Trevor L, Quinn, Lynn

  • Authors: Amos, Trevor L , Quinn, Lynn
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/270902 , vital:54490 , xlink:href="https://hdl.handle.net/10520/AJA10113487_559"
  • Description: The paper outlines the role of language in leaming and cognitive development and argues that management education and training needs to be integrated with language development to enable students to cope with the demands made of them at university as well as with those of careers in the business world. An integrated language developmEint project developed by the Depanment of Management and academic language practitioners at Rhodes Uhlvetsity is descriptionbed and suggestions are outlined as to how university Management departments can integrate language development in their mainstream teaching.
  • Full Text:
  • Date Issued: 1997

Metabolic responses in melanoma cells to combined nutrient supplementation

- Midgley, Nicola-Ann

  • Authors: Midgley, Nicola-Ann
  • Date: 1997
  • Subjects: Melanoma Tumors -- Growth
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4036 , http://hdl.handle.net/10962/d1004096
  • Description: This thesis examined the effect and biochemical mechanism by which combined vitamin E and C supplementation may influence tumour cell growth. The study initially addressed the effect of combined vitamin E succinate and Asc supplementation over a nutritional concentration range (5- 20μg/ml) and (25-50μg/ml) respectively, on the in vitro growth of non-malignant LLCMK and malignant BL6 cells. Supplementation of BL6 and LLCMK cells with combined vitamin E succinate and ascorbic acid, resulted in no significant increasing or decreasing trend in LLCMK cell growth, while in BL6 cells a significant decrease in cell growth was observed at all combined vitamin concentrations. It has been suggested that these vitamins may act synergistically to inhibit tumour cell growth through their antioxidant properties in quenching free radicals and lipid peroxidation and furthermore through their modulation of the activities of various enzymes and metabolites in the eicosanoid pathway. This study consequently investigated the effects of combined vitamin E succinate and ascorbic acid supplementation on these parameters. Throughout this study, emphasis was placed on the BL6 melanoma cells, as combined vitamin E succinate and ascorbic acid supplementation did not significantly affect growth or levels of secondary metabolites in the non-malignant LLCMK cells. Combined vitamin E succinate and ascorbic acid supplementation of BL6 cells resulted in a marked but non significant increase in free radical and a significant increase in lipid peroxidation levels. This prooxidant effect was accompanied by a significant decrease in BL6 cell growth, suggesting that the growth inhibitory effects of combined vitainin E succinate and ascorbic acid on BL6 cells in vitro was not mediated through their synergistic antioxidant properties. Vitamin E succinate is a nonphysiological antioxidant in its esterified form, hence cleavage of the succinate group must occur in order for ascorbic acid to interact with the free alcohol, vitamin E. The inability of combined vitamin E succinate and ascorbic acid to reduce free radicals and lipid peroxidation levels within BL6 cells may not be due to their ineffectiveness as antioxidants but rather the presence of other contributing factors which influence the oxidation state within the BL6 cells. Vitamin E is believed to modulate membrane-bound enzymes through membrane stabilization. Furthermore, the stabilizing effect of vitamin E may be enhanced by the ascorbic acid-sparing effect of vitamin E. Hence, this study investigated the effect of combined vitamin E succinate and ascorbic acid in modulating the activity of various enzymes and secondary messengers in the eicosanoid pathway. Supplementation with combined vitamin E succinate (5-20μg/ml) and ascorbic acid (25-50μg/ml) resulted in significant increases in phospholipase A₂, 5-lipoxygenase, cyclooxygenase and adenyl ate cyclase activity, with a significant decrease in BL6 cell growth. The possible synergistic action of these vitamins in terms of modulating membrane-bound enzymes was further substantiated by uptake and cellular distribution studies. Vitamin E succinate and vitamin E in the membrane fraction increased significantly compared to control cultures, while ascorbic acid levels were significantly higher in the stroma fraction when compared to membrane fractions. Consequently, another factor accounting for increased activities of phospholipase A2, 5-lipoxygenase and adenylate cyclase activities as a result of vitamin supplementation in BL6 cells may be an increased availability of Ca²+. Supplementation of BL6 cells with combined vitamin E succinate and ascorbic acid resulted in significant increases in intracellular Ca²+ levels at all combined vitamin groups. Furthermore, this increase in intracellular Ca²+ was positively correlated with cl1anges of the above-mentioned enzyme activities. Within the eicosanoid pathway, the rate of prostaglandin synthesis is regulated by phospholipase A₂ activity and arachidonic acid release, and the net prostaglandin production is dependent on cyclooxygenase activity, hence the effects of combined vitamin E succinate and ascorbic acid on arachidonic acid composition and prostaglandin production within BL6 cells was determined. The percentage arachidonic acid composition of the BL6 cells was elevated and inversely related to cell growth following combined vitamin E succinate and ascorbic acid supplementation. Prostaglandin E₂ and prostaglandin I₂ levels increased significantly, while those of prostaglandin D2 and prostaglandin F₂α increased markedly following supplementation of combined vitamin E succinate and ascorbic acid. These increases in prostaglandin levels were inversely related to BL6 cell growth, suggesting that the prostaglandins were involved in negative regulation of BL6 cell growth. When comparing the levels of prostaglandins, prostaglandin E2 levels were significantly higher when compared to prostaglandin D₂, prostaglandin F₂α and prostaglandin I₂ suggesting that vitamin E₂ succinate and ascorbic acid effects were mediated primarily through an increase in prostaglandin E2. Hence, prostaglandin E2 levels in combined vitamin E succinate and ascorbic acid appeared to be dependent on the amount of precursor present and the activity of its synthetic enzymes. This was confirmed when BL6 cells were supplemented with arachidonic acid. Arachidonic acid had an inhibitory effect on BL6 cell growth and also stimulated prostaglandin E₂ production. Prostaglandin E₂ levels are in turn believed to modulate adenylate cyclase activity in BL6 cells, hence it is reasonable to conclude that adenylate cyclase activity is dependent on prostaglandin E₂ levels. Combined vitamin E succinate and Asc supplementation to BL6 cells resulted in significant increases in adenyl ate cyclase and cyclic adenosine monophosphate, which again correlated with a significant decrease in cell growth. As cyclic adenosine monophosphate has a regulatory role in the cell cycle this study suggested that the effect of combined vitamin E succinate and ascorbic acid supplementation was mediated through the final effect provided by the second messenger, cyclic adenosine monophosphate. This was confirmed when BL6 cells were supplemented with dexamethasone, a phospholipase A₂ inhibitor. This treatment rsulted in combined vitamin E succinate and ascorbic acid having no inhibitory effect on BL6 cell growth. Cyclooxygenase activity, prostaglandin E₂ levels, adenylate cyclase activity and cyclic adenosine monophosphate levels were significantly lower in dexamethasone-treated cells compared to non-treated dexamethasone cultures. The reason for the increased free radical and lipid peroxidation levels in BL6 cells was further investigated. Cyclooxygenase enzymes are believed to generate free radical species during catalytic activity. Analysis of free radical and lipid peroxidation levels following supplementation with dexamethasone revealed markedly lower free radical and significantly lower lipid peroxidation levels in comparison with control cultures and non dexamethasone-treated cultures. These results suggest that the observed increases in free radical and lipid peroxidation levels in BL6 cells supplemented with combined vitamin E succinate and ascorbic acid were indirectly due to the increase in cyclooxygenase activity in these cells.
  • Full Text:
  • Date Issued: 1997

Metallophthalocyanine catalysed electroreduction of nitrate and nitrite ions in alkaline media

- Chebotareva, Natalia, Nyokong, Tebello

  • Authors: Chebotareva, Natalia , Nyokong, Tebello
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293301 , vital:57073 , xlink:href="https://doi.org/10.1023/A:1018466021838"
  • Description: Copper, cadmium, lead and bismuth (> 5 μg ml−1) are determined by adsorptive cathodic stripping voltammetry (AdCSV) on a mercury film glassy carbon electrode, using catechol, 4-methylcatechol, 4-t-butylcatechol and resorcinol as complexing ligands. Complexes of lead, copper and bismuth with resorcinol showed the largest increase in current with increase in metal concentration, whereas complexes of these metals with 4-t-butylcatechol showed the lowest current response. Cadmium showed a different behaviour from the other three metals in that the highest current response was observed with 4-methylcatechol. The four metals could be determined simultaneously in the presence of resorcinol, although considerable interference was observed between bismuth and copper.
  • Full Text: false
  • Date Issued: 1997

Modelling parallel and distributed virtual reality systems for performance analysis and comparison

- Bangay, Shaun Douglas

  • Authors: Bangay, Shaun Douglas
  • Date: 1997
  • Subjects: Virtual reality Computer simulation
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4657 , http://hdl.handle.net/10962/d1006656
  • Description: Most Virtual Reality systems employ some form of parallel processing, making use of multiple processors which are often distributed over large areas geographically, and which communicate via various forms of message passing. The approaches to parallel decomposition differ for each system, as do the performance implications of each approach. Previous comparisons have only identified and categorized the different approaches. None have examined the performance issues involved in the different parallel decompositions. Performance measurement for a Virtual Reality system differs from that of other parallel systems in that some measure of the delays involved with the interaction of the separate components is required, in addition to the measure of the throughput of the system. Existing performance analysis approaches are typically not well suited to providing both these measures. This thesis describes the development of a performance analysis technique that is able to provide measures of both interaction latency and cycle time for a model of a Virtual Reality system. This technique allows performance measures to be generated as symbolic expressions describing the relationships between the delays in the model. It automatically generates constraint regions, specifying the values of the system parameters for which performance characteristics change. The performance analysis technique shows strong agreement with values measured from implementation of three common decomposition strategies on two message passing architectures. The technique is successfully applied to a range of parallel decomposition strategies found in Parallel and Distributed Virtual Reality systems. For each system, the primary decomposition techniques are isolated and analysed to determine their performance characteristics. This analysis allows a comparison of the various decomposition techniques, and in many cases reveals trends in their behaviour that would have gone unnoticed with alternative analysis techniques. The work described in this thesis supports the Performance Analysis and Comparison of Parallel and Distributed Virtual Reality systems. In addition it acts as a reference, describing the performance characteristics of decomposition strategies used in Virtual Reality systems.
  • Full Text:
  • Date Issued: 1997

Multivariate analysis of honeybee populations, Apis mellifera Linnaeus (Hymenoptera: Apidae), from western central Africa morphometries and pheromones

- Radloff, Sarah E, Hepburn, H Randall

  • Authors: Radloff, Sarah E , Hepburn, H Randall
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451963 , vital:75091 , https://hdl.handle.net/10520/AJA10213589_298
  • Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations along a transect through three ecological-climatological zones in Cameroon. There are three distinct homogeneous populations and two zones of hybridization. These bees are designated as A. m. adansollii Latreille whose area of distribution is intruded by an A. m. montieola-like montane group of bees and a third group, A. m. jemertitica Ruttner. The delineation of the hybrid zones is supported by intercolonial variance spectra and these significant asymmetries are coincident with transitions between the ecological-climatological zones.
  • Full Text:
  • Date Issued: 1997

Multivariate analysis of honeybees, Apis mellifera Linnaeus (Hymenoptera: Apidae), of the Horn of Africa

- Radloff, Sarah E, Hepburn, H Randall

  • Authors: Radloff, Sarah E , Hepburn, H Randall
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451987 , vital:75093 , https://hdl.handle.net/10520/AJA10213589_154
  • Description: Morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to delineate the honeybee populations of the Horn of Africa. Four discrete and statistically homogeneous populations were identified: A. m. jemenitica Ruttner, A. m. bandasii Mogga, A. m. sudanensis Rashad in Ethiopia and an unclassified group in southwestern Somalia. Areas of high intercolonial variance are interpreted as zones of hybridization between the populations.
  • Full Text:
  • Date Issued: 1997

Ndemka

- Group performance, Group composition, Dargie, Dave

Ndinothixo omkhulu

- Performer not specified, Composer not specified, Dargie, Dave

Negotiating a comprehensive long-term relationship between South Africa and the European Union: from free trade to trade and development

- Cross, Peter John

  • Authors: Cross, Peter John
  • Date: 1997
  • Subjects: Economic development -- South Africa -- 1994- , European Economic Community , European Economic Community countries -- Foreign economic relations -- South Africa , South Africa -- Foreign relations -- European Economic Community countries
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2768 , http://hdl.handle.net/10962/d1002978 , Economic development -- South Africa -- 1994- , European Economic Community , European Economic Community countries -- Foreign economic relations -- South Africa , South Africa -- Foreign relations -- European Economic Community countries
  • Description: On 10 May 1994 the European Union offeredSouth Africa a package of measures to ... send a strong political signal to the incoming govemment and to the South African population, thus proving its firm determination to support the transition towards democracy and its willingness to contribute to the reconstruction and economic development of South Africa after the elections. This package consisted of two parts: 1. A series of short term implementations to take place with immediate effect to help South Africa's development and transition, and 2. An offer to negotiate a comprehensive long-term relationship with South Africa should the new government so request. South Africa accepted the European Union's offer to negotiate a long-term relationship, and in response requested membership of the structure governing the Union's relations with the rest of the countries in Sub-Saharan Africa and some countries in the Caribbean and Pacific, namely the Lomé Convention. Due to various incompatibilities South Africa was not allowed to join this organisation. In its place the European Union offered to negotiate an agreement with South Africa that would lead to a Free Trade Area. This agreement was in keeping with the rules as laid down by the World Trade Organisation. It envisaged the lowering of tariffs and trade barriers between the Union and South Africa over a period not exceeding 12 years, allowing for asymmetry in terms of time constraints in implementation only. South Africa saw this type of agreement as inconsistent with the desire expressed by the European Union to support the countries development and the integration of the Southern African region. In its place South Africa proposed a new concept in trade agreement, this concept, known as the Trade and Development Agreement, embodied both trade liberalisation and support for development. This agreement would introduce a new paradigm of thought to govern trade between developed countries and developing countries within the World Trade Organisation's rules. This paper explores the events that unfolded in these negotiations. It attempts to discover whether, in the current global environment, it is possible, or beneficial, for the developed world to act in an altruistic manner towards another state in order to assist its development.
  • Full Text:
  • Date Issued: 1997

New placoderm fishes from the Late Devonian of South Africa

- Long, John A, Anderson, M Eric, Gess, Robert W, Hiller, Norton

  • Authors: Long, John A , Anderson, M Eric , Gess, Robert W , Hiller, Norton
  • Date: 1997
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/72763 , vital:30108 , https://doi.org/10.1080/02724634.1997.10010973
  • Description: New placoderm fishes are described from a black shale lens in the Famennian Witpoort Formation, near Grahamstown, South Africa. Arthrodires include a new species of Groenlandaspis, G. riniensis sp. nov., a new genus of groenlandaspidid, Africanaspis doryssa gen. et sp. nov., and a new species of the antiarch Bothriolepis, B. africana sp. nov. This is the first record of the ubiquitous genera Bothriolepis and Groenlandaspis from the African continent. The South African placoderm fauna has demonstrable links with the eastern Gondwana faunas in the close affinity of the Bothriolepis africana with B. barred of Antarctica, and the high diversity of groenlandaspid species, especially the presence of a very high crested form having affinities to Tiaraspis.
  • Full Text: false
  • Date Issued: 1997

Newsletter of the Self-Employed Womens Union - No.21

- SEWU

  • Authors: SEWU
  • Date: 1997
  • Subjects: SEWU
  • Language: Xhosa, Afrikaans
  • Type: text
  • Identifier: http://hdl.handle.net/10962/155026 , vital:39834
  • Description: Ngomhla we 12 ku May uSEWU wamenywa ukuba azokwenza iziphakamiso kwikomiti ejongene nokulinganiswa kwabantu ngokungakhethe sini (Commission for Gender Equality)malunga nemeko yamakhosikazi azisebenzelayo. Lekomishoni yonyulwe ngo 1997. Ngethuba ekwakuqala ingxoxo zopolitiko malunga noMzantsi Afrika omtsha, kwavunyelwana ukuba urhulumente omtsha akasayi kuvumela ukuxhatshazwa kwabantu ngesini. Yaye bayakuqinisekisa ukuba kuphunyezwa umthetho kwakhiwe nepolisi ezilungiselele ukukhusela oko.
  • Full Text:
  • Date Issued: 1997

Newsletter of the Self-Employed Womens Union - No.22

- SEWU

  • Authors: SEWU
  • Date: 1997
  • Subjects: SEWU
  • Language: Afrikaans, Xhosa
  • Type: text
  • Identifier: http://hdl.handle.net/10962/155100 , vital:39855
  • Description: Die Derde Jaarlikse Konferensie van SEWU sal vanaf 22 -24 Julie plaasvind. Dit is die eerste nasionale konferensie vandat SEWU buite die grense van KwaZulu- Natal begin organiseer het. Afgevaardigdes van die Wes-Kaap sal ook by hierdie Konferensie wees. SEWU lede sal afgevaardigdes uit hulle eie geledere kies om hulle by hierdie Konferensie te verteenwoordig. Daar is ongeveer 48 SEWU takke waarvan 15 in die KwaZulu-Natal se landelike gebiede is. Een afgevaardigde word vanuit elke 20 opbetaalde lede in ’n tak verkies. Ons verwag tussen 100 en 150 afgevaardigdes.
  • Full Text:
  • Date Issued: 1997

Newsletter of the Self-Employed Womens Union - No.22

- SEWU

  • Authors: SEWU
  • Date: 1997
  • Subjects: SEWU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/155037 , vital:39835
  • Description: Die Derde Jaarlikse Konferensie van SEWU sal vanaf 22 -24 Julie plaasvind. Dit is die eerste nasionale konferensie vandat SEWU buite die grense van KwaZulu- Natal begin organiseer het. Afgevaardigdes van die Wes-Kaap sal ook by hierdie Konferensie wees. EWU lede sal afgevaardigdes uit hulle eie geledere kies om hulle by hierdie Konferensie te verteenwoordig. Daar is ongeveer 48 SEWU takke waarvan 15 in die KwaZulu-Natal se landelike gebiede is. Een afgevaardigde word vanuit elke 20 opbetaalde lede in ’n tak verkies. Ons verwag tussen 100 en 150 afgevaardigdes.
  • Full Text:
  • Date Issued: 1997

Newspapers in education programmes and South African youth: a survey of the relationship between South African school-goers and newspapers in Esikhawini, Kwazulu-Natal

- McComb, Roslin Vanessa

  • Authors: McComb, Roslin Vanessa
  • Date: 1997
  • Subjects: Newspapers in education -- South Africa , School children -- South Africa -- KwaZulu-Natal -- esikhawini , Newspapers in education
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3465 , http://hdl.handle.net/10962/d1002920 , Newspapers in education -- South Africa , School children -- South Africa -- KwaZulu-Natal -- esikhawini , Newspapers in education
  • Description: This study examines the relationship which scholars have with newspapers against the background of a Newspapers in Education (NIE) programme in two black South African primary schools. Considering the presence of newspapers in the class as a medium of instruction, a number of factors are found to influence the -relationship which scholars have with newspapers. These factors are: scholars' access to newspapers; the nature of lessons using the newspaper; the character of the newspaper used in NIE and the context of education at the particular schools, including the attitudes and organisational abilities of both teachers and the principal. A description and analysis of this relationship is conducted in terms of the knowledge, attitudes and behaviour which scholars had -in te1ation to newspapers. This research is qualitative, undertaken from a constructivist-interpretative approach, and is set within international and South African contexts. The findings are relevant to understanding NIE programmes' interface with scholars' educational performance and with newspaper marketing objectives, as well as to the theorisation of NIE practices.
  • Full Text:
  • Date Issued: 1997

Ngobani na

- Performer not specified, Composer not specified, Group Composition, Dargie, Dave

Nguban' ixesha

- Performer not specified, Composer not specified, Dargie, Dave

NoAndile igama lomz' wam

- Group performance, Group Composition, Dargie, Dave

NoAndile igama lomz' wam

- Performer not specified, Composer not specified, Group Composition, Dargie, Dave

NoAndile igama lomz' wam

- Performer not specified, Composer not specified, Group Composition, Dargie, Dave

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