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Rights to reality - the right to social security, with particular emphasis on the legal resources centre's welfare project in the Eastern Cape

  • Authors: Delany, Mairéad Christine
  • Date: 2003
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:21027 , http://hdl.handle.net/10962/6052
  • Description: This research addresses the question of whether the courts have been used effectively to enforce the right to social security in the Eastern Cape. The nature of the right to social security is discussed and placed in the context of constitutional developments in South Africa and South Africa's obligations in terms of international law. The enforcement of socio-economic rights and legislation regarding social assistance is also discussed in detail, along with the problems associated with the social security system such as the gaps in the system, the impact of HIV / AIDS and the problems created by the amalgamation of various administrations. The history of the Legal Resources Centre, a non-governmental organisation which has been involved in public interest law for twenty four years, is detailed. The Grahamstown office's litigation campaign against the Eastern Cape Department of Welfare is then discussed and six landmark cases are analysed in detail. A discussion of the jurisprudential significance and impact of each case on the development of South African administrative and constitutional law follows. A series of stories reported in the press illustrate the human aspect of the campaign and balance the legal argument. These stories may suggest that the Constitution's commitment to social justice and the government's commitment to the principles of Batho Pete are merely noble ideals for many people in the province, but it is argued that the LRC's campaign has made a vast contribution towards making these ideals a reality on the ground. The expert opinions of various groups interviewed during the course of this research regarding the impact of the LRC's litigation campaign are discussed, and the conclusion is drawn that it has indeed had a positive effect. They include paralegals at Advice Offices around the province, legal practitioners from the LRC, a private legal practitioner, several representatives of the Black Sash, a former MEC for Health and Welfare in the Eastern Cape Provincial Government, an official from the Department, and a leader of the Anglican Church in the province. In conclusion it is submitted that, but for the LRC's litigation campaign, the situation in the Eastern Cape would not have improved to the extent it has and may even have deteriorated further. Furthermore, it is submitted that as a result of the litigation campaign, the right to social security, and particularly the right to social assistance, is more accessible and more of a reality on the ground.
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  • Date Issued: 2003

Riverine macroinvertebrate responses to chlorine and chlorinated sewage effluents-Acute chlorine tolerances of Baetis harrisoni (Ephemeroptera) from two rivers in KwaZulu-Natal, South Africa

  • Authors: Williams, M L , Palmer, Carolyn G , Gordon, Andrew K
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , report
  • Identifier: http://hdl.handle.net/10962/437990 , vital:73427 , ISBN 0378-4738 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/WaterSA_2003_04_19.pdf
  • Description: Chlorine is widely used in South African sewage treatment works, and despite its volatility is likely to have a considerable impact on riverine ecosystems. This paper considers the results of acute (96 h) toxicity responses to chlorine of riverine mayfly nymphs Baetis harrisoni col-lected from the small, relatively uncontaminated suburban Westville Stream, KwaZulu-Natal and from the more severely impacted Umbilo River, which flows through the industrial area of Pinetown, KwaZulu-Natal, South Africa.
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  • Date Issued: 2003

Sandy beach morphodynamics and macrobenthic communities in temperate, subtropical and tropical regions : a macroecological approach

  • Authors: Soares, Alexandre Goulart
  • Date: 2003
  • Subjects: Seashore ecology , Intertidal ecology , Benthos
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:11077 , http://hdl.handle.net/10948/293 , Seashore ecology , Intertidal ecology , Benthos
  • Description: A comprehensive study involving 52 microtidal beaches spanning from reflective to dissipative states and located in tropical, subtropical and temperate regions in the Atlantic, Pacific and Indian oceans was carried out to unravel the relative roles of latitude and beach morphodynamics in determining beach macrobenthic species richness, abundance, biomass and mean individual body sizes. Since beach slope is one of the most important factors controlling beach fauna, a model based on beach geometry was applied to the sub-aerial beach deposit to understand the role of physical factors in predicting equilibrium beach slopes. Additionally, it was tested if the occurrence of beach types is related to latitude, and how physical factors change with morphodynamics and latitude. The beach morphometric model makes three assumptions: 1) that the cross-section of a beach deposit is equivalent to a right-angled triangle, 2) that the physical hydrodynamic factors (wave height and spring tide amplitude) and the beach deposit characteristics (sand grain size, beach slope and width) are interchangeable with their geometric counterparts producing an equation to explain beach geometry, and 3) that the predicted beach slope is in equilibrium with the hydrodynamic and sedimentological forces. The equation for predicting beach slope was derived and then tested against field data collected over 52 beaches. The predicted slopes were not significantly different from the observed slopes of the studied natural beaches. However some estimated slopes were different than observed ones. Possible sources of deviation between calculated and observed slopes may be the systematic sampling errors associated with field data. Alternatively, observed slopes could be the result of past hydrodynamic conditions, explaining the differences with the slopes calculated by the beach morphometric model, which assumes a state of equilibrium between beach slope and hydrodynamic conditions. A higher correlation of beach faunal structure with observed slopes rather than with present hydrodynamic conditions could then be indicative of faunal responses to previous hydrodynamic conditions in the same way was the observed slopes. The beach morphometric model could therefore be also useful in predicting faunal responses to changing hydrodynamic conditions. Since the model does not consider wave period, it is concluded that further tests should be done using laboratory and time-series field data and incorporating the role of wave period and beach permeability to ascertain its predictive value. Tropical regions had significantly more beaches in a reflective state than temperate and subtropical regions. Some tropical beaches were fronted by coral reefs, which not only provided coarse carbonate particles, but also additionally dissipated the low wave energy present in these climatic areas. Only one dissipative beach with high energy was found in the tropics, in southeast Madagascar. Temperate and subtropical regions, on the other hand, were dominated by dissipative beaches with medium to fine sands. Open oceanic reflective beaches were non-existent in the subtropics and rare in temperate regions, only occurring in estuaries, enclosed bays or on islands facing the continent. Intermediate beaches were more common in the subtropics but also occurred frequently in the other two regions, having higher energy in temperate regions. Reflective beaches had significantly steeper slopes, coarser sands, smaller waves and shorter swash lengths when compared to dissipative beaches. Additionally, reflective beaches were narrower, had deeper water tables and in consequence shorter saturation zones. Wave periods and surfzone widths were on average larger on dissipative than on reflective beaches. The frequency of occurrence of beach types is therefore related to the climatic signature of each latitude. Mid latitudes would be predicted to have more dissipative beaches with large and long waves because of their proximity to the storm generating belt around 50-60° S - these beaches will have a predominantly finer sands because of the input by rivers in rainy areas. Lower latitudes will have more reflective beaches due to a modal low energy wave climate and also because of the presence of inshore and offshore biotic structures such as coral reefs that dissipate even more the energy from the waves. Tropical and subtropical regions had larger marine species pools than temperate regions. After controlling for biogeographical differences in total species pool, dissipative beaches were on average significantly richer than intermediate and reflective beaches. Crustaceans were also more diverse on dissipative beaches, this difference being not significant for either molluscs or polychaetes. Significant relationships were found between total beach species richness (with or without terrestrial species), crustacean and mollusc species richness with beach morphodynamics as represented by the Dean’s index. Indices incorporating the role of tide, such as BSI, were less important in predicting species richness on the microtidal beaches studied here. Several other physical factors were also significantly correlated with species richness, the most important being the Beach Deposit Index, i.e. BDI, a composite index of beach slope and grain size. The highest correlation was between BDI and relative species richness, i.e. local beach species richness / regional species richness. Total regional marine species richness was higher in Madagascar and North Brazil (tropical beaches) than in Southeast Brazil (subtropical), or the West Coast of South Africa and South-Central Chile (temperate beaches). Not only was the pool of species capable of colonizing beaches richer in tropical and subtropical regions, but also local diversity of each morphodynamic beach type was higher among tropical beaches than their temperate counterparts. Although the results of this study agree with the predictions of the swash exclusion hypotheses, several reflective and intermediate beaches had higher species richness than predicted before and this seems to be linked to the presence of finer sediments and a less turbulent flow for larvae to settle. It is concluded that beach species richness is not necessarily controlled by one major morphodynamic parameter; this control is complex and probably involves multiple interacting biotic (biological interactions) and abiotic (e.g. grain size, wave height, beach slope and width, water table) factors. Species richness seems to be controlled on two different scales: on an evolutionary one where tropical and subtropical regions have higher regional and local diversity due to higher speciation rates; and on an ecological scale, where fine grained sand beaches have their carrying capacity enhanced by higher larval settlement rates and survival of recruits towards adulthood. On average dissipative beaches had higher total densities and macrofaunal abundances than reflective ones. Crustaceans, terrestrial species and cirolanid isopods such as Excirolana spp. were also more abundant on dissipative beaches. The difference was not significant for molluscs and polychaetes. Significant relationships were found between total abundance, crustacean species richness and beach morphodynamics as represented by the Dean’s index. Again, BSI was less important than individual physical factors in determining faunal abundance on the studied microtidal beaches. Several other physical factors were also significantly correlated with abundance, the most important being the Beach Deposit Index (BDI). The highest correlation was between BDI and total macrofaunal abundance. Factors related to surf zone processes, and possibly productivity, were highly correlated with total community, crustaceans, Excirolana spp. and terrestrial species abundances. The abundances of polychaetes and molluscs were better correlated with factors related to the beach deposit (BDI, slope, grain size and water table depth). Significant differences were observed between latitudinal regions for the average beach and also for each beach type. In general temperate beaches harboured larger community densities and abundances, and also crustacean, Excirolana spp. and terrestrial abundances. Mollusc and polychaete abundances were larger on subtropical and tropical beaches. The control of abundance on a sandy beach is complex and involves multifactorial processes at evolutionary and ecological scales. At evolutionary scales animals seem to attain higher abundances in the region where they first evolved, e.g. amphipods and isopods in temperate regions. At ecological scales they attain higher abundances where productivity is higher (total macrofaunal, crustaceans, Excirolana spp., terrestrial spp.) or where the settlement environment is more benign (molluscs and polychaetes). Dissipative beaches supported larger average and total community biomass than reflective beaches. Crustaceans, terrestrial species and cirolanid isopods such as Excirolana spp. also had larger biomass on dissipative beaches. The difference was not significant for molluscs and polychaetes. Significant relationships were found between the biomass of community and taxonomic groups with beach morphodynamics as represented by the Dean’s morphodynamic index. On the microtidal beaches studied here, BSI was less important than other morphodynamic indices and single physical factors in determining faunal biomass and mean individual body size. Surf zone characteristics such as wave height, period and surf zone width had the highest correlations with community, crustacean.
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  • Date Issued: 2003

Seasonal phenology of the diamondback moth, Plutella xylostella (L.), (Lepidoptera: Plutellidae), and its parasitoids on canola, Brassica napus (L.), in Gauteng province, South Africa

  • Authors: Mosiane, M S , Kfir, Rami , Villet, Martin H
  • Date: 2003
  • Language: English
  • Type: text , Article
  • Identifier: vital:6856 , http://hdl.handle.net/10962/d1011139
  • Description: Canola, Brassica napus L. (Brassicaceae), is a relativelynewcrop in SouthAfrica. Several insect pests, including diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), that attack cruciferous vegetables, also attack canola. The aims of this study were to determine the seasonal phenology of P. xylostella populations on canola, and the composition, relative abundance and seasonal phenology of parasitoids attacking P. xylostella on this crop. Diamondback moth adults were monitored with synthetic sex-pheromone traps. Larval and pupal populations of P. xylostella were monitored weekly for three years at Bapsfontein and Rietondale in Gauteng province. Samples of diamondback moth larvae, pupae and parasitoid cocoons were collected and transported to the laboratory. Parasitoids that emerged were identified and their incidence recorded. Berlese funnel catches were used as an indicator of the accuracy of the visual counts. The infestation level of P. xylostella larvae was high from May to August at Rietondale, while at Bapsfontein it was high from September to December. There was a high correlation (r=0.79, P<0.001) between pheromone trap catches and subsequent larval infestations at Bapsfontein. The pheromone traps indicated that diamondback moth adults were present throughout the year. Berlese funnel catches indicated that a large number of larvae, especially first instars, were overlooked during visual plant scouting. Parasitism rates were often very high, reaching 90–100 %. The following parasitoids were recorded from field-collected P. xylostella: the larval parasitoids Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae) and Apanteles halfordi Ullyett (Hymenoptera: Braconidae), the larval/pupal parasitoids Diadegma mollipla (Holmgren) (Hymenoptera: Ichneumonidae) and Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae), the pupal parasitoid Diadromus collaris (Gravenhorst) (Hymenoptera: Ichneumonidae), and the hyperparasitoids Mesochorus sp. (Hymenoptera: Ichneumonidae) and Pteromalus sp. (Hymenoptera: Pteromalidae). Cotesia plutellae was the most abundant parasitoid throughout the study.
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  • Date Issued: 2003

Self-Assembled Monolayers of Cobalt and Iron Phthalocyanine Complexes on Gold Electrodes

  • Authors: Ozoemena, Kenneth I , Nyokong, Tebello , Westbroek, Philippe
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/290363 , vital:56743 , xlink:href="https://doi.org/10.1002/elan.200302753"
  • Description: The self-assembling of the octa(hydroxyethylthio)-metallophthalocyanine {MOHETPc (M=Co and Fe)} complexes and their similar analogues, octabutylthiometallophthalocyanine {MOBTPc (M=Co and Fe)} complexes on gold electrodes are investigated. Comparative surface voltammetric insights into their distinct self-assembling properties with respect to the passivation of Faradaic processes and surface coverages, including their solution electrochemistry, suggest different orientations and non-cleavage of their CS bonds. In the pH 2−9 range, the reversible [M(III)Pc(−2)]+ / [M(II)Pc(−2)] redox couples show potential shifts close to −59 mV / pH. The gold electrodes modified with the SAMs of these species show electrocatalytic activity towards the oxidation of thiols (L-cysteine, homocysteine and penicillamine) and thiocyanate in acidic media with detection limits in the region of 10−7–10−6 mol dm−3. These monolayers are stable and easily reproducible.
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  • Date Issued: 2003

Shakespeare in the Media: Newspaper Response to Shakespeare in Post-Independence West Bengal, 1948-97, Lipika Sidkar: book review

  • Authors: Wright, Laurence
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/455757 , vital:75454 , https://hdl.handle.net/10520/EJC48012
  • Description: Reading this book is a cultural experience in itself, from the typography and layout, to the scholarly conventions observed, the treatment of the subject matter and its arrangement. I found it fascinating, perhaps exaggeratedly so because of abysmal ignorance on my part concerning the voluminous scholarly and text-book literature on Shakespeare which has streamed from the presses of the sub-continent.
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  • Date Issued: 2003

Simulation and visualization of fire using extended Lindenmayer systems

  • Authors: Zaniewski, Tomasz , Bangay, Shaun D
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/433303 , vital:72960 , https://doi.org/10.1145/602330.602337
  • Description: This research introduces a method of using Lindenmayer Systems to model the spreading and behavior of fire inside a factory building. The research investigates the use of L-System propagated fires for determining factors such as where the fire is most likely to spread first and how fast. It also looks at an alternative way of storing the Lindenmayer System, not in the form of a string but rather as a graph. A variation on the building and traversal process is also investigated, in which the L-System is traversed depth first instead of breadth first. Results of fire propagation are presented and we conclude that L-Systems are a suitable tool for fire propagation.
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  • Date Issued: 2003

Small-scale fisheries as a vehicle for rural development : a case study of two villages in the former Ciskei, Eastern Cape Province, South Africa

  • Authors: Seti, Simpiwe
  • Date: 2003
  • Subjects: Small-scale fisheries -- South Africa -- Eastern Cape Fisheries -- South Africa -- Eastern Cape Fishes -- South Africa -- Eastern Cape Rural development -- South Africa -- Eastern Cape Fish trade -- Developing countries Fisheries, Cooperative -- Developing countries
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3346 , http://hdl.handle.net/10962/d1006016
  • Description: This thesis examines small-scale rural fisheries which were initiated in two villages by the Department of Ichthyology and Fisheries in conjunction with the Institute of Social and Economic Research in 1997. The main objective for undertaking the study was to determine the potential of the fisheries to serve as viable and sustainable options that could contribute towards rural development in the area of study. To examine the contribution made by the small-scale fisheries towards rural development in the villages, it is imperative to have an understanding of the context in which they were established as well as the prospects for sustainable development. It is argued in this study that despite the significant contribution made by inland rural fisheries in improving rural livelihoods they are still accorded minimal support and attention in South Africa. As an illustration of the important role played by rural fisheries, case studies from Malawi and Zimbabwe have been drawn into the study with a view to providing lessons for rural areas of South Africa. The study took place at a time when natural resources in the villages were significantly declining and environmental degradation reaching uncontrollable proportions, so there is an urgent need to secure an alternative mode of subsistence for the population in the villages. Development interventions by the state and non-governmental organisations in the study area have not been sustainable and they collapsed within a short period of time. A case in point is the Tyefu irrigation scheme, which was initiated in the villages but, owing to various factors, it failed leaving the villagers with a diminished mode of subsistence, thus providing the impetus for the implementation of small-scale rural fisheries. In order for small-scale fisheries to be sustainable it is essential to adopt models that are aimed at sound natural resource use and management. This study has raised various issues pertinent to natural resource use and management in the study area. A model for management of natural resources that involves and aims to empower local communities in the management of the fisheries is presented in the study. It has also been demonstrated that rural fisheries in the study area comply with the model. Finally, the study draws the conclusion that small-scale fisheries in the villages contribute towards rural development, however, there are constraints that need to be eradicated.
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  • Date Issued: 2003

Solvent effects on the photochemical and fluorescence properties of zinc phthalocyanine derivatives

  • Authors: Ogunsipe, Abimbola Olukayode , Maree, D , Nyokong, Tebello
  • Date: 2003
  • Language: English
  • Type: Article
  • Identifier: vital:6586 , http://hdl.handle.net/10962/d1004162 , http://dx.doi.org/10.1016/S0022-2860(03)00155-8
  • Description: The effects of solvents on the singlet oxygen, photobleaching and fluorescence quantum yields for zinc phthalocyanine (ZnPc) and its derivatives; (pyridino)zinc phthalocyanine ((py)ZnPc), zinc octaphenoxyphthalocyanine (ZnOPPc) and zinc octaestronephthalocyanine (ZnOEPc), is presented. The effects of the solvents on the ground state spectra are also discussed. The largest red shift of the Q band was observed in aromatic solvents, the highest shift being observed for 1-chloronaphthalene. Higher singlet fluorescence quantum yields were observed in THF for ZnPc and ZnOPPC. Also in the same solvent phototransformation rather than photobleaching was observed for ZnOPPc. Split Q band in the emission and excitation spectra of ZnOPPc was observed in some solvents and this is explained in terms of the lowering of symmetry following excitation.
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  • Date Issued: 2003

South Africa within SADC : hegemon or partner?

  • Authors: Molefi, Tebogo Shadrack
  • Date: 2003
  • Subjects: Southern African Development Community , Political stability -- Africa, Southern , South Africa -- Economic conditions , South Africa -- Foreign relations -- Africa , South Africa -- Economic policy
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2866 , http://hdl.handle.net/10962/d1007674 , Southern African Development Community , Political stability -- Africa, Southern , South Africa -- Economic conditions , South Africa -- Foreign relations -- Africa , South Africa -- Economic policy
  • Description: This study attempts to make a contribution to the debate on the role of South Africa within Southern African Development Community. An attempt is made to analyse this role within the context of regional integration debate. This role has been conceptualised within the dichotomies of hegemon versus partner. The study argues that South Africa is a hegemon in the region of SADC, and that given its overarching economic dominance and it has the potential of establishing its hegemony in the region. It maintains that there are several factors, which could facilitate South Africa's hegemonic dominance such as in military, technology and manufacturing sector. It concludes by arguing that given the changing geopolitical factors both within the region and the globe impedes South Africa from firmly expressing this hegemonic dominance. Furthermore, South Africa's pioneering role in the struggle to change the status quo globally in favour of the Southern states is another crucial factor, which imposes limitations on its hegemonic intentions regionally.
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  • Date Issued: 2003

South African research in the hydrological sciences: 1999-2002

  • Authors: Hughes, Denis A , Ashton, P , Gorgons, A , Jewitt, G P W , Schulze, R , Smithers, J , Pegram, G , Dube, R
  • Date: 2003
  • Language: English
  • Type: Article
  • Identifier: vital:7074 , http://hdl.handle.net/10962/d1009531
  • Description: The principal activities of South African researchers in hydrology and water resources during the reporting period have been concerned with ground- and surface-water interactions, rainfall-runoff modelling, the establishment of improved regional water resource databases, the management of transboundary water resource systems, the ecological reserve, and quantifying the impacts of streamflow reduction activities. Most of these studies have focused on supporting the radically new provisions of the National Water Act of 1998.
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  • Date Issued: 2003

Spatial and temporal occurrence of forensically important South African blowflies (Diptera: Calliphorida)

  • Authors: Williams, Kirstin Alexa
  • Date: 2003
  • Subjects: Blowflies -- South Africa , Forensic entomology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5617 , http://hdl.handle.net/10962/d1003217 , Blowflies -- South Africa , Forensic entomology
  • Description: Forensic entomology is an emergjng field in South Africa. Little is known about South African blowflies and factors that affect their use in a forensic context. This work provides a review and synthesis of previous work in South Africa and supplements some of the background and basic knowledge required for forensic entomology in South Africa. The seasonal occurrence of eight forensicaIIy important blowfly species was quantified by fortnightly trapping in Grahamstown, South Africa. The spatial distribution of each species was related to seasonal occurrence and habitat preference. Seasonal distributions of blowflies in carcasses in South Africa were obtained from the literature and compared to the seasonal trapping. By mapping South African locality records of forensicaIIy important blowflies and analyzing these records in a modified Principal Components Analysis of climatic data, the potential geographic distributions of each fly species was modeIIed. Most species were widespread, but Calliphora croceipalpis, Jaennicke, 1867, was found in cold places. This information is important for determining where certain species are likely to occur in forensic investigations. Nocturnal oviposition was examined in both field and laboratory experiments. Lucilia species could oviposit nocturnaIIy in the field, while Lucilia species, Chrysomya chloropyga, (Weidemann, 1818) and C. putoria (Weidemann, 1830) could oviposit nocturnaIIy in the laboratory. These findings are important factors in affecting the precision of estimates of a post mortem interval (PM!) by up to 12 hours. The thermophysiological ranges of four species of adult blowflies were determined by measuring onset temperatures of four significant behaviours: onset of neural activity; onset of coordinated movement; shade-seeking and death. There was a sexual size dimorphism in Lucilia species, Chrysomya chloropyga and Calliphora croceipalpis with females being larger than males. Chrysomya megacephala (Fabricius, 1794) had an unexpectedly high death threshold, while Calliphora croceipalpis had the lowest death threshold of the flies tested. These points were related to the seasonal and geographic occurrence of each species, to nocturnal activity and placed in a forensic context.
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  • Date Issued: 2003

Spray Oils Beyond 2000 Sustainable Pest and Disease Management, GAC Beatie, DM Watson, ML Stevens, DJ Rae and RN Spooner-Hart (Eds.): book review

  • Authors: Villet, Martin H
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/442099 , vital:73955 , https://hdl.handle.net/10520/EJC32548
  • Description: Spray oils gained popularity as pesticides in the 1950s but were subsequently displaced in the market by synthetic compounds. With recent trends in legislation relating to pesticide residues, interest in these oils is reviving. This saw expression in the convening of the first international conference on spray oils in Sydney, late in 1999. The proceedings of that conference form the contents of this book, which features over 70 papers. The compilers clearly feel that one of the most important contributions is a newly proposed international classification scheme for spray oils, including explicit chemical standards and a common nomenclature, which is aimed at overcoming the existing ambiguous and dialectal system. However, the volume will have relevance to a much wider audience because it provides a broad overview of research into this neglected form of crop protection.
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  • Date Issued: 2003

Stability studies on some substituted aminobenzoic acids

  • Authors: Rotich, Moses Kipngeno
  • Date: 2003
  • Subjects: Aminobenzoic acids Aminobenzoic acids -- Stability Salicylic acid
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4347 , http://hdl.handle.net/10962/d1005012
  • Description: he thermal behaviour in the solid state of various substituted aminobenzoic acids (3-aminobenzoic acid (3-ABA), 4-aminobenzoic acid (4-ABA), 3-aminosalicylic acid (3-ASA), 4-aminosalicylic acid (4-ASA), and 5-aminosalicylic acid (5-ASA), as well as the "parent" benzoic acid (BA) and salicylic acid (SA) as reference substances, and possible decomposition products: 2-aminophenol (2-AP), 3-aminophenol (3-AP) and 4-aminophenol (4-AP), has been examined. The various sets of isomers studied showed considerable and interesting differences. Most sublimed well before melting, generally with an increasing rate of mass loss beyond their very different melting points. The existence of ranges of isomers allows for the comparison of their behaviour, including such aspects as melting, vaporisation, and the influence of products on the course of decomposition of initially-solid reactants. The differences in behaviour of 4-ASA and 5-ASA were the most remarkable, with 5-ASA being far more stable and apparently not decarboxylating readily, while 4-ASA sublimed at temperatures below the melting point, becoming less stable and decarboxylating in the liquid form. There is also a marked difference in the thermal behaviour of 3-ASA, as compared with 4-ASA and 5-ASA. It decarboxylated at higher temperatures (260°C) than 4-ASA (150°C). The addition of the possible decomposition products to these compounds showed faster decomposition for 4-ASA mixed with 3-AP. The sodium salts of 3-ASA and 4-ASA decarboxylate while that of 5-ASA did not. Binary mixtures of the substances listed above with beta-cyclodextrin (BCD), hydroxypropylbeta-cyclodextrin (HPBCD) and gamma-cyclodextrin (GCD) were prepared (by simple physical mixing or by kneading with a solvent) and were then examined for possible interactions using DSC, TG-FTIR, HSM, XRD and NMR. Generally, kneaded mixtures showed greater changes in thermal behaviour from that of the individual components than the physical mixtures, but changes in the physical mixtures were also significant. Comparison of the effects of the different CDs on the thermal behaviour of individual ASA isomers showed that HPBCD has the greatest interaction with 3-ASA and 5-ASA, followed by GCD, while BCD generally showed the least interactions. For 4-ASA, the effect of GCD is more marked than for 3-ASA and 5-ASA. GCD has the largest molecular cavity.
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  • Date Issued: 2003

Stakeholder perceptions of success factors in an academically successful Swazi high school in Manzini, Swaziland

  • Authors: Mabuza, Johannes Tshotsho
  • Date: 2003
  • Subjects: St Michael's High (Manzini, Swaziland) Education -- Swaziland Education, Secondary -- Swaziland Academic achievement -- Swaziland High school students -- Swaziland Education -- Parent participation -- Swaziland Educational leadership -- Swaziland School management and organization -- Swaziland
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1901 , http://hdl.handle.net/10962/d1006223
  • Description: In contrast with the large number of poorly performing schools in Swaziland over the past decade (1991-2000), a few schools have managed to attain consistently good results. One such school is St Michael's High. This study draws on the perceptions of different major stakeholders at St Michael's of factors deemed to have contributed to academic success at the school. The study thus follows Fertig (2000), who advocates research in effective schools to be done by looking at the perceptions of different stakeholders rather than in relation to an objective checklist. In this study, St Michael's High is found to be an effective school. Its experience can play a vital role in helping other ineffective and failing schools to improve their academic standing and tarnished public image, provided the schools unreservedly commit themselves to changing their ways. This investigation is aimed at understanding the roles which the school leadership and associated stakeholders have played in making St Michael's an exemplary school in Swaziland. Its findings indicate that the schools that themselves take the initiative to improve their effectiveness are the ones which are successful, which accords with the consensus in research literature on school effectiveness. The evidence gathered in this study suggests that St Michael's is characteristic of such effective schools. Since this is a qualitative interpretive case study on perception of success factors in a girls' high school within the city of Manzini, interviews comprising semi-structured questions were highly useful in tapping the understanding of how various stakeholders contribute to the academic achievement of students in the school. The findings, organised in the form of themes, help illuminate what appears to be a systematic and well-focussed approach toward the academic development of the school and the fulfilment of its goals. Every aspect of the school system is thoroughly explored. The validity of the stakeholders' claim that St Michael's High is a dream school for most Swazi children is verified by the school's examination results for the past decade. But what the research reveals are the cultural, academic, social, and moral values and beliefs which serve as a strong anchor for the school leadership and management, and without which St Michael's as an organisation would be unable to meet the challenge of implementing academic and national reconstruction.
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  • Date Issued: 2003

Stepping into history : biography as approaches to contemporary South African choreography with specific reference to Bessie's Head (2000) and Miss Thandi (2002)

  • Authors: Snyman, Johannes Hendrik Bailey
  • Date: 2003
  • Subjects: Head, Bessie, 1937-1986 , Maqoma, Gregory -- Miss Thandi , Derrida, Jacques -- Criticism and interpretation , Biography , Choreography -- South Africa -- History
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2154 , http://hdl.handle.net/10962/d1004678
  • Description: This mini-thesis is located in historical discursive practices, choreographing history, biography as a source for making dance in South Africa and choreographic transformations in South African choreography since the 1994 democratic elections. Derridian concepts of deconstruction will be referenced in an attempt to focus the argument of this research, which comments on choreographic transformations since 1994, by subverting the influence of the 'violent hierarchies' enforced by the apartheid regime on South African cultural life and choreographic identity. The researcher draws on these considerations in order to explore the hybrid nature of South African choreography that has emerged since 1994. Chapter one examines the fallacious nature of historical discourse through a consideration and application of Derrida's notions of deconstruction and fabrication. Chapter two explores the notion of choreographing history in theatre through a focus on the objective/subjective fallacy and the history of the body as a textual medium. Chapter three focuses the study specifically in biography as a discourse within the idea of theatre. This approach to biography can be encapsulated by the phrase 'telling lives'. This chapter also explores the relationship between the traditional binaries of writing as a purely cerebral act and choreography as a purely visceral experience. Chapter four brings the focus to the specific post-apartheid South African context. This chapter considers the hybrid forms of dance emerging in South Africa as well as the notion of protest in relation to theatre and dance. The final chapter is an investigation and analysis of two choreographic works created by South African choreographers since 1994 in relation to biography and concepts of deconstruction. These works are Gary Gordon's Bessie's Head (2000) and Gregory Maqoma's Miss Thandi (2002). The focus of the analysis also reveals the inherent difficulty in objective interpretation, and considers the problematics of collaboration and autobiography when choreographing within a biographical context.
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  • Date Issued: 2003

Strategic change and its impact on the organisational structure of Pennypinchers (PTY) Ltd.: a case study

  • Authors: Kemp, Leona
  • Date: 2003
  • Subjects: Organizational change , Strategic planning
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:10877 , http://hdl.handle.net/10948/262 , Organizational change , Strategic planning
  • Description: During the 1990’s many South African companies experienced the need to change and adapt. This was largely because of the environmental changes brought about by a new political regime. One of these changes was the exposure of South African companies to global competition. Because the South African business environment had remained relatively static during the 1980’s, many companies had no idea of how to manage change when it became necessary for economic survival. This inability led to the demise of many organisations. As change as a business concept covers a vast area, the main objective of this study was to isolate one area of change and examine it in a practical context. The chosen area was the relationship, if any, between strategy and organisational structure. The practical context chosen was an organisation, which had recently undergone strategic change. The research methodology for this study included the conducting of an intensive literature study, to determine the academic stance on the strategy/structure relationship. Various academic theories were examined to determine whether there was a relationship between the two concepts, and if so, what the relationship should be. This provided a background for the practical evaluation. Literary opinion showed consensus that there was indeed a relationship between the two; in fact the one was integral to the success of the other. That is, if an organisation chooses to consider adopting a change strategy, it should carefully consider its impact on organisational structure. To summarise, in a situation of change, structure should support strategy to ensure a successful transition. An empirical study was then conducted at Pennypinchers (Pty) Ltd , which had recently undertaken to implement a change strategy. The focus of the empirical study was the relationship between the chosen change strategy and organisational structure. The aim was to determine whether the strategy had an impact on organisational structure, and if so, whether the structure underwent During the 1990’s many South African companies experienced the need to change and adapt. This was largely because of the environmental changes brought about by a new political regime. One of these changes was the exposure of South African companies to global competition. Because the South African business environment had remained relatively static during the 1980’s, many companies had no idea of how to manage change when it became necessary for economic survival. This inability led to the demise of many organisations. As change as a business concept covers a vast area, the main objective of this study was to isolate one area of change and examine it in a practical context. The chosen area was the relationship, if any, between strategy and organisational structure. The practical context chosen was an organisation, which had recently undergone strategic change. The research methodology for this study included the conducting of an intensive literature study, to determine the academic stance on the strategy/structure relationship. Various academic theories were examined to determine whether there was a relationship between the two concepts, and if so, what the relationship should be. This provided a background for the practical evaluation. Literary opinion showed consensus that there was indeed a relationship between the two; in fact the one was integral to the success of the other. That is, if an organisation chooses to consider adopting a change strategy, it should carefully consider its impact on organisational structure. To summarise, in a situation of change, structure should support strategy to ensure a successful transition. An empirical study was then conducted at Pennypinchers (Pty) Ltd , which had recently undertaken to implement a change strategy. The focus of the empirical study was the relationship between the chosen change strategy and organisational structure. The aim was to determine whether the strategy had an impact on organisational structure, and if so, whether the structure underwent.
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  • Date Issued: 2003

Structural and synthetic investigations of diterpenoid natural products from southern African marine invertebrates

  • Authors: Gray, Christopher Anthony
  • Date: 2003
  • Subjects: Ethyl acetoacetate Diterpenes Limpets -- South Africa Natural products -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4349 , http://hdl.handle.net/10962/d1005014
  • Description: This thesis is divided into two parts. The first part (Chapter Two) documents a bioassay guided investigation of the ethyl acetate extracts of four marine invertebrates from Mozambique (an Irciniid sponge, a Haliclona sp. sponge, an ascidian tentatively identified as Diplosoma sp., and the soft coral Cladiella kashmani). Eight known compounds [ilimaquinone (2.1), renierone (2.7), N-formyl-1,2-dihydrorenierone (2.8), 1,6-dimethyl-7-methoxy-5,8-dihydroisoquinoline-5,8-dione (2.9), mimosamycin (2.10) 7Z-allylidene-5-hydroxy-7,7a-dihydro-2H-cyclopenta[b]pyran-6-one (2.11), flaccidoxide (2.18) and 11S,12S-epoxycembra-1Z,3E,7E-trien-14S-ol (2.19)] and a new diterpene [13S,14R-diacetoxy-11S,12R-epoxycembra-1Z,3E,7E-triene (2.20)] were isolated and identified using standard spectroscopic techniques. Anomalies in the published spectral data of 2.1 and 2.8 were exposed and corrected, and the absolute stereochemistry of the cembrane diterpenes 2.18 and 2.20 established using the modified Mosher’s method. The comparative activities of the nine natural products against four cancer cell lines (A549, LOX, OVCAR3, SNB19) are reported. The second part of the thesis (Chapter Three – Chapter Six) is concerned with an ecological, structural and synthetic study of diterpenes from the endemic South African pulmonate limpet Trimusculus costatus. Two new labdane diterpenes [6b,7a-diacetoxylabda-8,13E-dien-15-ol (3.10) and 2a,6b,7a-triacetoxylabda-8,13E-dien-15-ol (3.11)] were isolated from T. costatus and evaluated for anti-feeding activity against the common predatory fish Pomadasys commersonnii. A strategy for the semi-synthesis of 3.10 from rhinocerotinoic acid (4.14), a diterpene reportedly present in the ubiquitous South African shrub Elytropappus rhinocerotis, was devised in order to allow further bioactivity tests to be performed and unequivocally assign the unknown absolute stereochemistry of the T. costatus metabolites. Attempts to isolate rhinocerotinoic acid from local specimens of Elytropappus rhinocerotis were unsuccessful, and as the repetition of a published synthesis of 4.14 from (-)-sclareol (4.15) gave rhinocerotinoic acid in unacceptably low yields with poor stereoselectivity, an improved synthesis of 4.14 is presented. Comprehensive studies using hispanone (5.1) as a model compound showed that 6,7-dioxygenated labda-8-enes could be prepared from compounds possessing a 7-oxo-labda-8-ene skeleton with some degree of stereocontrol. In the process, fourteen new hispanone analogues were prepared and most of these were tested for activity in a suite of ten agro-chemical assays. The novel compound 7b-hydroxy-9a-carbonitrile-15,16-epoxylabda-13(16),14-dien-6-one (5.34) exhibited significant activity against the crop fungus Phytophthora infestans and is currently being subjected to further agro-chemical tests. Unfortunately, the results from the oxygenation study performed on the model compound 5.1 could not be directly extrapolated to rhinocerotinoic acid. Attempts to prepare the naturally occurring 3.10 from 4.14 via an alternative route were unsuccessful but yielded an analogue of 3.10 in which the substituents at C-6 and C-7 are in a diequatorial rather than a diaxial configuration.
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  • Date Issued: 2003

Structure and cytology of the testes of Labeo victorianus (Pisces: Cyprinidae)

  • Authors: Rutaisire, Justus , Muwazi, Ruth T , Booth, Anthony J
  • Date: 2003
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/446798 , vital:74561 , https://doi.org/10.1080/15627020.2003.11657199
  • Description: Testes macromorphology and histomorphology together with sperm cytology are described for a potamodrometic cyprinid fish, Labeo victorianus, from Lake Victoria. Testes were found to be paired and elongate, suspended by a mesorchium on either side of the swim bladder. A sperm duct ran along the medial surface of each testis before fusing caudally to form the common sperm duct that terminated at the urogenital pore. Main sperm ducts were lined by simple columnar epithelium supported by a wall with elastic connective tissue and a few smooth muscle cells. The tunica albuginea divided the testes into lobules, which contained spermatogenetic cell types. The lobules, released spermatozoa into an anastomosing tubule network that emptied directly into the main sperm duct. Valve like structures were present along the length of the sperm duct and are proposed to regulate milt flow. Three types of somatic cells were observed at the onset of gonadal recrudescence; plasma and intralobular somatic cells were within the lobules, while Leydig cells were close to the blood vessels in the interstitium. Maturing testes were characterized by the dominance of spermatocytes and spermatids, both contained in cysts. Spermatozoa, arising from the spermatids, filled the lobular lumen in mature testes after spermatocyst rupture. In post spawned testes, Type A spermatogonia dominated. Testicular regression was not characterized by spermatozoa phagocytosis, rather via apoptosis.
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  • Date Issued: 2003

Structures and struggles of rural local government in South Africa: the case of traditional authorities in the Eastern Cape

  • Authors: Ntsebeza, Lungisile
  • Date: 2003
  • Subjects: Local government -- South Africa -- Eastern Cape Tribal government -- South Africa -- Eastern Cape Political leadership -- South Africa -- Eastern Cape Tribal government -- South Africa -- History South Africa -- Politics and government
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3304 , http://hdl.handle.net/10962/d1003092
  • Description: This thesis is about the political implications of the constitutional recognition of the hereditary institution of traditional leadership in post-1994 South Africa for the democratization process in the rural areas of the former Bantustans. The thesis is organized around three related conceptual, historical and political questions. The conceptual question deals with the meaning of democracy in rural areas under the jurisdiction of traditional authorities. The historical question traces how the institution and traditional authorities have survived to the present post-colonial period. Lastly, this study investigates the political issue of why an ANC-led government came to recognize the institution. The focus of the thesis is the sphere of rural local government in the Xhalanga district, where these issues are best illustrated. The thesis argues that the institution of traditional leadership and its officials survived precisely because they were incorporated into the colonial and apartheid administrative structures in the project of indirect rule. Traditional authorities were central to the apartheid policy of retribalisation, which was essentially a form of control of Africans in the Bantustans. Rural residents engaged in fierce struggles against the imposition of rural local government structures such as the District Council and Tribal Authorities. In so far as traditional authorities were part of government structures, they could not avoid being targets in these struggles. In explaining the recognition of the institution of traditional leadership, the thesis focuses on the policies of the ANC, the majority party in the Government of National Unity, towards traditional authorities. Organisationally weak on the rural grounds, the ANC operated through what they considered to be “good/progressive/comrade chiefs”. The ANC had hoped that these traditional authorities would accept a non-political ceremonial role. However, traditional authorities have rejected this ceremonial role. Their refusal, coupled with the ANC’s ambivalence in resolving the tension imply, the study concludes, that the (political) citizenship rights of rural people are partial: they are neither citizens nor subjects.
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  • Date Issued: 2003
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