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Small business development in Duncan Village: towards a new development framework

Southern African Journal of Gerontology, volume 5, number 1, April 1996

  • Authors: Ferreira, Monica (editor) , Moller, Valerie , HSRC/UCT Centre for Gerontology
  • Date: 1996
  • Subjects: Gerontology -- South Africa , Older people -- Care -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:8072 , http://hdl.handle.net/10962/d1012865
  • Description: [From Editorial] This issue comprises a transdisciplinary mix of interesting and relevant papers ranging from a community-development intervention, to gerontolinguistics, to guidelines for new legislation, to community services in China. The issue begins with an article on infrastructure and equity for the elderly, in which authors Ross, Lerer and Phillips investigate the attitudes of older residents of Elim, a village situated in South Africa's Western Cape province, towards electrification of their village and homes. The creation of basic infrastructure in historically-disadvantaged areas throughout South Africa is a priority under the government's RDP. However, in this case study of Elim, the utility company which provides electricity to the village failed to consult the elderly residents on the developmental intervention and the benefits which electrification might have for them. The majority of the older residents who were interviewed were consequently negative about this new energy source. The advantages which electricity has over other fuels have distinct health and other developmental benefits, and in rural households older members are important decision makers on energy use. The study's findings indicate that developmental interventions in ruralbased communities should include a social-marketing component targeting older members of the community. The article by Makoni on discourse practices in first-time encounters between old and young Xhosa-speaking women represents an exciting development in gerontological research in the Southern African region. As far as we know, this is a first report on a linguistics study in an older population in the region. In his analysis of the conversations, Makoni notes the sociohistorical background against which the old women try to retain status and respect. He points out that while the elderly are a marginalized group, the youth in South African society have become empowered through their contributions to the political changes, which along with other social changes are seen by some to destabilize traditional seniority respect norms. , In his article Van Dokkum makes out a case for the development of legislation to protect older South Africans against abuse. He uses examples of new South African legislation to deter child abuse and vast legislation in the United States to protect older Americans, in outlining a proposal for local activists to campaign for adequate protection of elderly citizens. Zhu gives us an update on a massive community social-services programme for older people being implemented in the People's Republic of China. The programme partly aims to assist an increasing number of older people who find that they are no longer able to live with kin and must live independently. The programme already serves a staggering proportion of China's 104 million persons aged 60 years and above, although it is estimated that it currently only meets 30 percent of the demand. pensions and household structure in Namibia by Adamchak published in SAJG Volume 4, No 2 (October 1995), and Adamchak's response are welcome additions to this number. The journal encourages debate on papers that it publishes, and the letters also reflect the development and growth of gerontology and research on ageing in the Southern African region. Finally, gerontolinguist Makoni reviews Hamilton's (1994) book in which the author analyses her conversations with Elsie, an Alzheimer's disease patient in a "total institution" (Goffman, 1961). The book contributes to understanding of losses and changes in language use in sufferers of this disease as the dementia progresses. Makoni proposes topics for studies on this subject which might be carried out in Southern African countries, where the majority of dementing older Africans are cared for within the community and not in a long-term care institution.
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  • Date Issued: 1996

Southern African Journal of Gerontology, volume 5, number 2, October 1996

  • Authors: Ferreira, Monica (editor) , Moller, Valerie , HSRC/UCT Centre for Gerontology
  • Date: 1996
  • Subjects: Gerontology -- South Africa , Older people -- Care -- South Africa
  • Language: English
  • Type: Text
  • Identifier: vital:8073 , http://hdl.handle.net/10962/d1012867
  • Description: The October 1996 number of SAJG is a special issue on "Gender, ageing and empowerment in Africa." The guest editor of the special issue is Maria Cattell of Millersville University, Pennsylvania, USA, who has conducted substantial research on older Kenyans and more recently on Zulu grandmothers. Dr Cattell is the President of the global Association of Anthropology and Gerontology (AAGE). The issue will comprise research papers from authors in several African countries, and will provide valuable data and experience of ageing in Africa for transnational comparison.
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  • Date Issued: 1996

Spectroelectrochemical studies of tin (IV) diphthalocyanine

  • Authors: Nensala, Ngudiankama , Nyokong, Tebello
  • Date: 1996
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293436 , vital:57085 , xlink:href="https://doi.org/10.1016/0277-5387(95)00325-1"
  • Description: Cyclic voltammetry of tin(IV) diphthalocyanine (Pc2Sn) in dichloromethane containing TEAP shows two reduction couples at −0.56 and −0.89 versus saturated calomel electrode (SCE) and one oxidation couple at 0.35 V versus SCE; all were quasireversible one-electron couples. The oxidation couple corresponds to [Pc(−1)SnIVPc(−2)+/Pc(−2)SnIVPc(−2) and the reduction couples to Pc(−2)SnIVPc(−2)/[Pc(−3)SnIVPc(−2)]− and [Pc(−3)SnIVPc(−2)]−/[Pc(−3)SnIVPc(−3)]2−, respectively. The electronic absorption spectra of the various reduced or oxidized tin(IV) diphthalocyanine species are reported.
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  • Date Issued: 1996

Stars to Buses to Stars-The Evolution of Remote Studio Access Topologies

  • Authors: Foss, Richard
  • Date: 1996
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/427444 , vital:72439 , https://www.aes.org/e-lib/browse.cfm?elib=7428
  • Description: This paper describes an ongoing investigation into the use of networking technology to provide access to shared music studio resources. The goal of the investigation is to see whether it is possible to provide remote, shared, and centralized access to studio resources. The investigation has followed an evolutionary path along which three configurations have been identified and completely or partially implemented. The configurations provide various paths for the flow of MIDI, audio, and studio control data.
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  • Date Issued: 1996

Structures and thermal behaviour of some monooxalato and dioxalato metal complexes

  • Authors: Bacsa, John
  • Date: 1996
  • Subjects: Oxalates -- Research , Crystallography -- Research , Chemistry, Inorganic -- Research
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4351 , http://hdl.handle.net/10962/d1005016 , Oxalates -- Research , Crystallography -- Research , Chemistry, Inorganic -- Research
  • Description: The crystal structure of Ba [Cu(C₂0₄)₂(H₂O)].5H₂O has been determined using single crystal X-ray diffractometry. It crystallises in the triclinic system, space group Pī , with a = 6.539(2) Å, b = 9.211(3) Å, c = 10.928(3) Å, a = 85.42(3)°, β = 79.22(3)° , γ = 80.30(3)°, V = 636.08(8)ų and Z = 2. The structure consists of [Cu(C₂0₄)₂(H₂O)]²⁻ ions weakly bridged by barium ions and water molecules. The copper(II) ions are in a tetragonally elongated square-pyramidal environment with some trigonal distortion. The two oxalate groups occupy the equatorial positions and a water molecule occupies the axial position. The barium ion is surrounded by nine oxygens: five oxygens from water molecules and four oxygens from oxalate groups. The thermal behaviour of Ba [Cu(C₂0₄)₂(H₂O)].5H₂0 in N₂ has been examined using thermogravimetry (TG) and differential scanning calorimetry (DSC). The dehydration starts at relatively low temperatures (~80°C), but continues until the onset of the decomposition (~280°C). The decomposition takes place in two major stages. The mass of the intermediate after the first stage corresponded to the formation of barium oxalate and copper metal and, after the second stage, to the formation of barium carbonate and copper metal. The enthalpy for the dehydration was found to be 311 ±30 kJ mol⁻¹. The overall enthalpy change for the decomposition of Ba[Cu(C₂0₄)₂]in N₂ was estimated from the combined area of the peaks of the DSC curve as -347 kJ mol⁻¹. The kinetics of the thermal dehydration and decomposition were studied using isothermal TG. The dehydration was strongly deceleratory and the α-time curves could be described by the three-dimensional diffusion (D3) model. The values of the activation energy and the pre-exponential factor for the dehydration were 125 ±4 kJ mol⁻¹ and (1.38 ±0.08)x10¹⁵ min⁻¹, respectively. The decomposition was complex, consisting of at least two concurrent processes. The decomposition was analysed in terms of two overlapping deceleratory processes. One process was fast and could be described by the contracting-geometry model with n = 5. The other process was slow and could also be described by the contracting-geometry model , but with n = 2. The values of Eₐ and A were 206 ±23 kJ mol⁻¹ and (2.2 ±O.5)xl0¹⁹min⁻¹, respectively, for the fast process, and 259 ±37 kJ mol⁻¹ and (6.3 ±1.8)x10²³min⁻¹, respectively, for the slow process.The crystal structure of zinc oxalate dihydrate ([Zn(C₂0₄)(H₂O)₂]n) has also been determined by X-ray diffraction methods. It crystallises in the monoclinic system, space group C2/c with a = 11.786(2) Å, b = 5.397(1)Å, c = 9.712(1) Å, B = 126.19(5)°, V = 498.58(8)ų, Z = 4 and R = 0.037 for 435 absorption-corrected independent reflections and 50 parameters. The asymmetric unit consists of half the monomeric unit [Zn(C₂0₄)(H₂O)₂). The structure consists of infinite, linear chains of zinc ions bridged by oxalate groups. The geometry of the coordination polyhedron surrounding the zinc ion is octahedral, with the oxalate oxygens occupying the equatorial positions and water molecules occupying the axial positions.
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  • Date Issued: 1996

Suppositories: An underutilized dosage form

  • Authors: Webster, Jessica A , Dowse, Roslind , Walker, Roderick B
  • Date: 1996
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/184697 , vital:44264 , xlink:href="https://hdl.handle.net/10520/AJA16836707_911"
  • Description: The rectal route is useful for the delivery of both local acting and systemic drugs. In certain cases suppositories are the best form of therapy, or else they are an effective alternative when oral therapy is not possible. However; doctors rarely prescribe them and patients are often reluctant to use them. Understanding how suppositories work, and their numerous uses, can overcome the aversion to this particular dosage form. Pharmacists are in an ideal position to educate doctors, other health care providers, and patients, on the benefits of using suppositories and their correct use, and to offer advice on any problems associated with their use.
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  • Date Issued: 1996

Synthetic and mechanistic studies of heterocyclic systems

  • Authors: Deane, Philip O'Grady
  • Date: 1996
  • Subjects: Heterocyclic chemistry
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4379 , http://hdl.handle.net/10962/d1005044 , Heterocyclic chemistry
  • Description: A series of acrylate esters and selected analogues have been reacted with pyridine-2-,pyridine-3-, and pyridine-4-carboxaldehydes in the presence of diazabicyclo[2,2,2]octane (DARCO) to afford a range of Baylis-Hillman products. The pyridine-2-carboxaldehyde-derived products have been acetylated using acetic anhydride and the kinetics of the thermal cyclisation of the acetylated compounds to indolizines was investigated using proton NMR spectroscopy. The first-order kinetics of the cyclisation has been confirmed and the influence of substituents on the first-order rate constant, kₒbs has been examined. The kinetic data has been shown to be consistent with the previously proposed mechanism in which loss of the acetate group is ratedetermining. Each of the cyclisations was also monitored at three different temperatures permitting evaluation of the activation parameters. The Baylis-Hillman products and related acetylated derivatives were treated at room temperature with sodium methylthiolate; the hydroxy precursors were observed to undergo conjugate addition with a degree of diastereocontrol but the acetylated derivatives favoured an apparent SN¹ displacement of the acetate group.
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  • Date Issued: 1996

Teaching the principles of ecology in the urban environment: an investigation into the development of resource materials

  • Authors: Wagiet, Mogamat Fadli
  • Date: 1996
  • Subjects: Environmental education -- South Africa Educational change -- South Africa
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1799 , http://hdl.handle.net/10962/d1003684
  • Description: The combined potential of two crucial factors in 1993, which afforded the promotion of socially just and ecologically sustainable ways of living, led to the instigation of this research project. The first was the imminence og our first democratic election; the second was the possible introduction of environmental education into formal education. In the light of these momentous shifts, it became apparent to me that teachers would have to radically transform their practices in order to play their part in transforming society from the dark days of apartheid into one of equity and harmony. The implications of these factors precipitated the falling into place of the rationale for my research: teachers had to look for professional development experiences which could facilitate the creation of alternative ways of thinking and doing. As a result, I approached a group of biology and geography teachers on the Cape Flats and, after protracted discussions, we decided to examine the potential of the urban environment for the teaching of ecology from the perspective of socially just and environmentally sustainable living. Out of this decision was born this study, which aimed at examining whether this process could, as a means to professional development, be a 'moment' in our journey to becoming transformative intellectuals. From this aim, the central research question emerged: Can emancipatory action research play a role in empowering teachers to become transformative intellectuals? The study consisted of five stages: - exploring the problem by reviewing the literature on the research problem; - the semi-structured interviews; - five workshops; - the 'sensing the urban environment' fieldtrip; and, - the various evaluation sessions. What we achieved during this research project, firstly, was a better understanding of our practices, which led us to seeing our roles as teachers differently and altered our pedagogical approaches. Secondly, this process developed the belief within ourselves that we, as teachers, can and should make a difference to the educational world in which we live. Lastly, this process laid the foundation for continued collaborative action by the participants. This process taught us that educational transformation is difficult and painful, and that present educational structures are not conducive to change. Nonetheless, in the historical context of this research, emancipatory action research was successful in giving us a consciousness-raising experience and closed the rhetoric-reality gap as we engaged in praxis (the practitioners developing and implementing their own curriculum). If we, as transformative intellectuals, are to engage in intellectual labour in the future, we are not only going to need to change our way of thinking and doing but will have to create an enabling infrastructure to realise this as well. We will, in addition, have to change the structures of the institutions in which we work in order to practise as transformative intellectuals.
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  • Date Issued: 1996

Technologies of the self in the writings of William S Burroughs

  • Authors: Williams, Michael John
  • Date: 1996
  • Subjects: Burroughs, William S., 1914- -- Criticism and interpretation
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2225 , http://hdl.handle.net/10962/d1002268 , Burroughs, William S., 1914- -- Criticism and interpretation
  • Description: William Burroughs's profane life has been an affront to conventional morality, and his transgressive works have strained against the thematic and formal boundaries of literature. Although he has remained a problematic figure, he is gradually gaining recognition as a literary innovator. This thesis argues that his writings may be understood as technologies of the self, that is, the texts are tools that the writer Oses to transform himself. The Introduction outlines the problems that his writings pose for criticism; provides an overview of critical responses to his work; and demonstrates the appropriateness of Michel Foucault's theory of the technologies of the self as an approach to his texts. Furthermore, it makes a comparison between Burroughs's concerns and similar concerns evident in Foucault. The most prominent of these is a fear of control, and a desire to escape from control. It is argued that this similarity arises from the writers' shared experience of homosexuality in the twentieth century. This experience provokes them to undertake a·work of homographesis, in which they attempt to undermine the construction of identity in text, whilst simultaneously reinscribing identity in problematized autobiographical writing. Chapter One provides a corrective to the critical neglect of Burroughs's homosexuality and focuses on his sexual problematic as a key factor in the development of his literary style. It argues that the writer has an abject imagination that was precipitated by three principal traumatic experiences: his homosexuality, his addiction to opiates, and the accidental shooting of his wife. The chapter examines the way that the writer develops his unique literary style, the routine, in an attempt to express his psychic disintegration. The routine becomes the basic building block of Naked Lunch, serving both as a cathartic release of psychic anguish and as an attempt to subvert repressive social and linguistic structures. The metaphor of the anal aesthetic is introduced to describe the intersection of linguistic, psychic and political strategies in the texts. Chapter Two addresses the period,subsequent to Naked Lunch, in which Burroughs experimented extensively with the cut-up technique to develop a form of aleatory collage. The chapter argues that the writer hoped that the technique would enable him to transform himself and to~discover a new way of thinking, but suggests that its extreme nature both isolated him from his audience and intensified his psychic abjection. Chapter Three follows on from this to argue that the writer responds to the limitations of the cut-up in The Wild Boys by returning to a more intelligible form of writing. This return corresponds with an attempt to inscribe homosexual themes into his work directly. However, the combination of a homosexual agenda and the writer's defence against the identity loss of abjection leads him to assert a radical masculine identity that causes him to perceive women as the chief perpetrators of control. As a result, he rejects women from his mythological system. Chapter Four suggests that in Cities of the Red Night and The Place of Dead Roads the writer moves away from the radical queer agenda of The Wild Boys in the hope of discovering a form of ethics that avoids the traps of universalized humanism and the harsh "othering" of the queer agenda. The chapter draws a parallel between Burroughs's individualized ethics and Foucault's idea of an ethics grounded in aesthetic self-fashioning. Chapter Five examines The Western Lands, in which the writer confronts death in order to discover the nature of individual value in a normalized culture. Like Foucault, Burroughs believes that the most important task in a limited existence is the dandyistic creation of the self.
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  • Date Issued: 1996

TGWU 5th National Congress - Unite and fight for jobs and a living wage!

  • Authors: COSATU, TGWU
  • Date: July 1996
  • Subjects: COSATU, TGWU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/115446 , vital:34130
  • Description: TGWU is gearing up to influence and shape future transport policy with our Transport for the People policy document. A fresh perspective and preparedness to actively assert our vision for transport emerged at our 5th National Congress held in May at the Holiday Inn Garden Court in Johannesburg. More than 700 delegates representing 60 000 members countrywide gave concrete expression to our congress theme by adopting a call for a 24-hour general strike on 2 July in support of our demands around public transport policy. The call to action is a demonstration of our rejection of the Minister of Transport's intention to restructure the public transport industry (buses and Rail) through privatisation, thereby placing the future employment of workers under direct threat.
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  • Date Issued: July 1996

The alternative press in Namibia, 1960-1990

  • Authors: Heuva, William Edward
  • Date: 1996
  • Subjects: Press -- Namibia , Press and politics -- Namibia , Namibia -- Newspapers
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3434 , http://hdl.handle.net/10962/d1002888 , Press -- Namibia , Press and politics -- Namibia , Namibia -- Newspapers
  • Description: The study seeks to document the development of the alternative press in Namibia from 1960 to 1990. It traces the reasons for its emergence and outlines the stated aims and objectives in order to illustrate its attempts to nurture a culture - of colonial resistance. It is argued that structural factors such as funding, distribution, advertisements and ownership enabled the alternative press to operate outside the South African apartheid hegemony. The study explains how the intellectuals used the alternative press in their attempts to mobilise and organise colonised Namibians for social change. They did this by formulating and disseminating ideologically constructed discourses (messages) which challenged the colonial discourse. These messages were produced and directed towards a specific audience, the masses to whom the intellectuals were organically linked. Their primary news definers were also drawn from the ranks of these masses. It is further argued that the alternative press came to represent the colonised masses by voicing their needs and aspirations which were marginalised by the mainstream colonial media. Finally, a relatively detailed analysis of the content, the language used and the'messages carried by the alternative press has been made to demonstrate its political agenda, which was to empower the masses to achieve their objective - the attainment of political independence. These issues are analyzed against a background of theoretical frameworks which seek to explain how subordinated groups and classes in a state of domination sought to establish alternative channels of communication in the creation of a counter hegemonic order.
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  • Date Issued: 1996

The Bender Gestalt Test: an investigation into problems concerning administration and scoring and its application to low-educated adults

  • Authors: Dyall, Kate
  • Date: 1996
  • Subjects: Bender-Gestalt Test , Psychological tests , Brain-damaged children -- Psychological testing
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2968 , http://hdl.handle.net/10962/d1002477 , Bender-Gestalt Test , Psychological tests , Brain-damaged children -- Psychological testing
  • Description: The study investigates .the use of the Bender Gestalt Test (BGT) amongst low-educated adults. Three versions of the BGT are used in this study; the original 'copy' version as well as the 'immediate' and 'delayed'recall versions. This is done so as to expand the ability of the BGT to identify neurological impairment and to differentiate between this and functional impairment. A literature review explores the problems of standardization in the administration, scoring and application of all three versions of the test Suggestions are made to correct the problems identified and a novel system of scoring the recall versions are proposed, which allows for the comparison of results of the three versions of the test and which is based on Lacks's (1984) and Weiss's (1970) systems. Administration procedures were also developed to suit the context of the study. The copy, immediate and delayed versions of the BGT were administered to a group of 184 low-educated adults. Statistical analyses revealed significant education effects for the sample tested with regards to both test scores and performance time. The finding of an education effect for performance time is discussed at length, as some literature regards excessive time as a neurological indicator. An anomaly for the group with no education was found to exist, with the scores of these subjects not Significantly different from those with 4-6 years of education. Possible reasons for this were explored. In addition, the findings of this research revealed a plateau effect with those having less than 6 years of education scoring substantially lower than those with 7 years and more. The scores of adults with 7 and more years of education level out with no significant differences between educational levels. This appears to suggest that education effects rather than the developmental maturity level proposed by Koppitz, are involved. In addition, the scores of low-educated adults on the expanded Bender Gestalt Test were significantly lower than those of children with similar educational levels, in other studies. These findings and possible explanations are discussed. The study concludes by suggesting new research areas and emphasizing the urgent need for separate normative data on the expanded BGT for low-educated adults, and the establishment of appropriate 'cut-off' points.
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  • Date Issued: 1996

The development of an ecological model to determine flood release options for the management of the Phongolo floodplain in Kwazulu/Natal (South Africa)

  • Authors: Weldrick, Sarah Katharine
  • Date: 1996
  • Subjects: Flood control -- Environmental aspects -- South Africa -- KwaZulu-Natal -- Pongolo floodplain , Fishes -- Behavior
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5258 , http://hdl.handle.net/10962/d1005102 , Flood control -- Environmental aspects -- South Africa -- KwaZulu-Natal -- Pongolo floodplain , Fishes -- Behavior
  • Description: The Phongolo River floodplain in KwaZulu/Natal is a river-associated wetland which was subject to regular cycles of flooding in the past. The floods were associated with seasonal summer rainfall. Through the wet and dry cycles on the floodplain there was an alternation between the aquatic and terrestrial biomes. Many of the fishes on the floodplain are dependent on this cycle for their survival. The construction of the Pongolapoort Dam in 1969 has resulted in alterations to the timing, magnitudes and duration of the natural flooding events of the Phongolo River. This alteration has affected the fisheries. It is now necessary to simulate natural floods by artificial water releases from the dam. There are several demands on the water supply, so it has not always been possible to adhere to the natural flood regime. This necessitated the need for an integrated management programme to ensure the sustainability of the natural resources. A practical ecological model of the fishery was developed to determine an optimum flood release scenario for the floodplain. The relative abundances, distribution and species richness of the fishes were determined at various lakes and rivers on the floodplain. A community classification of the fishes was determined using TWINSPAN ordination. The potential yield of the fish at each site was calculated. Flood releases of varying magnitudes were simulated using Geographic Information Systems (GIS). This information was combined in a model which can be used by resource managers to estimate the percentage species compositions of fishes at each of the lakes, and to compare the actual harvest to the potential calculated sustainable yields of fishes for various flood release regimes. Subsistence agriculture and other beneficial ecological information can be incorporated into the model to determine the effect of different flood release options for the Phongolo floodplain.
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  • Date Issued: 1996

The development of the hydraulic biotope concept within a catchment based hierarchical geomorphological model

  • Authors: Wadeson, R A (Roy A)
  • Date: 1996
  • Subjects: Stream ecology -- South Africa Stream measurements -- South Africa Hydrology -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4826 , http://hdl.handle.net/10962/d1005501
  • Description: This thesis develops a technique for the identification, classification and quantification of instream flow environments. These features have been traditionally referred to as 'habitats' by lotic ecologists, in this research they are termed 'hydraulic biotopes'. The hydraulic biotope is the lowest of six nested levels of a hierarchical geomorphological model. This model has been developed as a tool to assist river managers, researchers and conservationists to categorise or classify rivers with respect to their geomorphic characteristics. Each level of the model provides data at a different level of resolution. This ranges from the broad scale catchment data to the site specific 'habitat' or hydraulic biotope data. Although this thesis is primarily concerned with the development of the hydraulic biotope, the interaction of all catchment variables needs to be recognised. Detailed analysis of hydraulic biotope data in the Buffalo River are presented within the broader hierarchical model. Consultation with lotic ecologists, together with a review of ecological literature, emphasised the need for a standardised terminology for the classification of ecologically significant instream flow environments. At present a fairly haphazard 'habitat' classification tends to be carried out by most researchers, this often leads to confusion in the identification and naming of different hydraulic biotopes ('habitats'). This confusion is exaggerated by the sharing of terminology between lotic ecology and fluvial geomorphology, usually for the categorisation of different types of features. A review of the ecological literature emphasises the importance of flow hydraulics within a river to describe the distribution of biota. The hydraulic variables considered to be most significant include velocity and depth. As river morphology directly determines the prevailing distribution of depth, velocity and substratum, it is obvious that there are important links to be made between fluvial geomorphology and lotic ecology. This thesis explores the potential of the hydraulic biotope as a tool to help develop those links. This thesis presents a standardised classification matrix for the identification of hydraulic biotopes. The matrix is simply based on water surface characteristics together with channel bed substratum. The validity of this matrix is tested by statistical analysis of hydraulic variables quantifying flow conditions within the various hydraulic biotope classes. Data is presented from four different river systems, each representing a different sedimentological environment. Where possible the influence of discharge has been considered. Results from more than 3000 data points show that hydraulic biotopes have distinct hydraulic characteristics in terms of velocity-depth ratio, Froude number, Reynolds number, 'roughness' Reynolds number and shear velocity. These hydraulic indices represent flow conditions both as an average within the water column, and near the bed. Statistical analysis shows that the hydraulic characteristics of the various hydraulic biotope classes are relatively consistent both within different fluvial environments and at different stages of flow. Unlike the morphological unit in which the hydraulic biotope is nested, in stream flow environments are shown to be temporally dynamic. Using the classification matrix as a tool for identification, hydraulic biotopes identified at one discharge are shown to be transformed from one class to another as a response to change in stage. The pattern of transformation is shown to be consistent within different sedimentological environments. An examination of the associations between hydraulic biotopes and morphological units demonstrates that, although some hydraulic biotopes are common to all morphological units (backwater pools, pools and runs), some features have specific associations. In this study rapids were found to be prevalent in bedrock pavement, bedrock pool and plane bed morphology, while cascades, chutes and riffles were common to plane bed, step and riffle morphology. Results from this research indicate that the hydraulic biotope, within the hierarchical geomorphological model, has the potential to aid the prediction of channel adjustment and associated 'habitat' (hydraulic biotope) transformation in response to changes in flow and sediment yield. These are likely to become increasingly important issues as South Africa strives to maintain a balance between the development of water resources to meet the needs of the rapidly expanding population, whilst at the same time maintaining the fluvial environment for sustainable use.
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  • Date Issued: 1996

The dynamics of space use in some Lake Malawi fishes

  • Authors: Robinson, Rosanna Lesley
  • Date: 1996
  • Subjects: Cichlids -- Nyasa, Lake Fishes -- Malawi Fishes -- Nyasa, Lake
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5264 , http://hdl.handle.net/10962/d1005108
  • Description: Behaviour and space utilisation of rock-dwelling cichlids were observed at Thumbi East Island, Lake Malawi. 1. Males of five species of the mbuna complex held long-term territories. Pseudotropheus elongatus "aggressive" vigorously defended a feeding area and sometimes a spawning site interspecifically, but did not feed in the peripheral part of their territory. Spawning sites of Pseudotropheus zebra, Pseudotropheus tropheops "orange chest", Labeotropheus fuelleborni, and Petrotilapia nigra were interspecifically-defended, while larger mating territories were defended against conspecific neighbours. Feeding areas were shared with many fish and often extended beyond the defended area. There was considerable variation in behaviour and space use within and between species and between times of day. 2. Non-territorial P. zebra used larger ranges than territorial conspecifics, and fed more on plankton, but individuals had preferred benthic feeding areas, often in conspecific territories. These 'floaters' were often aggressive. Both size and relative brightness independently predicted the outcome of aggressive interactions between floaters, and a site-specific dominance hierarchy was suggested, with some individuals appearing to be semi-territorial. 3. Males and females of 21 and 13 species respectively were found to establish temporary breeding territories. Overall breeding seasonality was bimodal, but reproductive timing and territory characteristics differed among species. Temporary territories had a considerable impact on the behaviour and habitat use of all resident mbuna species, even causing abandonment of territories. 4. Non-breeding Protomelas taeniolatus had limited home ranges, and showed little aggression. During the highly-synchronised reproductive season, males defended spawning sites and females fry-guarding territories. Most chases were directed towards the commonest fish, but predators were chased further and faster. Female behaviour changed over the guarding period. Females generally continued territorial defence after the brood had disappeared. Most broods contained fry of different sizes and species. Significant benefits were found for guarding females with clustered territories, but females did not appear to choose sites adjacent to conspecific parental females. 5. Territoriality in fish is taxonomically widespread and may serve several functions according to species, sex and developmental stage. It also varies according to genotype- and phenotype-limited strategies and short term costs and benefits. Territories may be simultaneously multifunctional.
  • Full Text:
  • Date Issued: 1996

The future role of TGWU in relation to Bus Transport in a changing environment

  • Authors: TGWU
  • Date: 1996
  • Subjects: TGWU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/111258 , vital:33425
  • Description: One will assume that the topic chosen for me to present a paper on,is no the one which looks on organisational and analytic development of TGWU. I will therefore focus on TGWU 's perspective on the current bus crisis future perspective and TGWU organisational role in the bus industry I felt it important to outline a brief background and our perspective cm the industry and how that dictates our attitude towards the industry. This paper is divided along the following sections;- Use of transport in internal economic and labour control. Contradictions and conflicts over transport policy. The future and its implications for Transport policy after apartheid. TGWU's organisational role and influence in the industry.
  • Full Text:
  • Date Issued: 1996

The geology of the Unki platinum-base metal deposit, Selukwe subchamber, great dyke, Zimbabwe

  • Authors: Murahwi, Charley Zvinaiye
  • Date: 1996
  • Subjects: Platinum ores -- Zimbabwe
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4962 , http://hdl.handle.net/10962/d1005574 , Platinum ores -- Zimbabwe
  • Description: This thesis focuses on platinu'm group element (PGE) mineralization in the Unki Section of the Selukwe Subchamber of the Great Dyke (Zimbabwe), and is based on drill hole intersections and underground and surface exposures of the Main Sulphide Zone (MSZ) which hosts significant concentrations of PGE. The petrological and geochemical data presented are part of a broader study currently underway and the present are restricted to the 2m section of the PGE-rich MSZ encountered in drill hole MR126. The PGE-rich MSZ at Unki is unique in having a shear, locally referred to as the Footwall Shear, developed at or close to its base . It is however, similar to the other PGE occurrences on the Great Dyke (MSZ) in having its hanging-wall restricted to within 1m of the websterite/bronzitite contact. Slight axial tilting to t he west is indicated by steeper dips on the eastern flank. The sulphide concentration wit hin the MSZ can be used as a rough guide to the PGE-rich zone, but is not sufficiently precise to be used in stope control. The visual identification of the potentially mineable zone remains a problem that is unlikely to be solved. Based on petrological evidence, the bulk of the sulphides with which the PGE are associated, are cumulus in status. This provides unequivocal evidence for an orthomagmatic origin of the MSZ. The dominant platinum group mineral (PGM) phase is the Arsenide/Sperrylite group which is most commonly found at the contact zones between base metal sulphides (BMS) and gangue. The PGM range up to 90 ~m in length. Geochemical evidence from the analyses of cumulate orthopyroxenes through the 2m PGE-rich MSZ interval at Unki reveals a trend of arked Fe enrichment upwards which corresponds to an enrichment in sulphide. This indicates that precipitation of sulphide was caused by fractionation with lowering of temperature in the magma. The Fe enrichment is followed by a reversal in Mg# of orthopyroxene which corresponds to the decrease in sulphide content, suggest i ng that the termination of the PGE-rich MSZ was due to an increase in temperature associated with an influx of new magma. Coupled with these magmatic events are a complex interplay of chemical and physical processes occurring at a critical stage in the overall fractionation of the Great Dyke magma chamber. The overall persistence and continuity of t he PGE zone as observed in the Unki area is consistent with the inferred orthomagmatic origin of the mineralization
  • Full Text:
  • Date Issued: 1996

The geology, geochemistry and stratigraphic correlations of the farm Rietfontein 70 JS on the south -eastern flank of the Dennilton Dome, Transvaal, South Africa

  • Authors: Crous, Stephanus Philippus
  • Date: 1996
  • Subjects: Stratigraphic correlation -- South Africa -- Transvaal , Geology, Stratigraphic , Geochemistry -- South Africa -- Transvaal , Geology -- South Africa -- Transvaal
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4960 , http://hdl.handle.net/10962/d1005572 , Stratigraphic correlation -- South Africa -- Transvaal , Geology, Stratigraphic , Geochemistry -- South Africa -- Transvaal , Geology -- South Africa -- Transvaal
  • Description: The study area is located between Loskop Dam and the town of Groblersdal, on the southeastern flank of the Dennilton dome, and is underlain by lithologies of the Pretoria Group, Bushveld Complex mafics and ultramafics and acid lavas that resort under the Rooiberg felsites. Field work comprised of geological mapping, soil-, hard-rock- and stream sediment geochemistry, various geophysical techniques and diamond drilling. The rocktypes that resembles the Rustenburg Layered Suite on the farm Rietfontein 70JS is subdivided into a Mixed Zone, Critical Zone and Main Zone, on grounds of geochemical and certain geophysical attributes. The Mixed Zone that overlies the Bushveld Complex floor-rocks, is furthermore separated into an i) Lower-, ii) Middle- and, iii) Upper Unit. The Lower Unit of the Mixed Zone consists primarily of magnetite-gabbros, iron-rich pegmatites, harzburgites and feldspathic pyroxenites. The Fe-rich constituents of this stratigraphic horizon generates a pronounced magnetic anomaly within the study area. On the basis of; amongst other parameters, Zr/Rb and Sr/Al₂0₃ ratios, the magnetite-gabbros are postulated to conform to lithotypes in the vicinity of magnetite layers 8 to 14 of Upper Zone Subzone B in a normal Bushveld Complex stratigraphical scenario. Similarly, it is argued that the feldspathic pyroxenites and norites that display elevated chromium values are analogues to normal Critical Zone rocktypes of the Rustenburg Layered Snite. A more elaborate and precise stratigraphic correlation for the Critical zone was, however, not possible. It is advocated that a volume imbalance was created by the hot, ascending mafic magmas of the intruding Bushveld Complex, resulting in the updoming of certain prevailing basement features such as the Dennilton Dome. In addition to this ideology, it is proposed that the Mineral Range Fragment is in fact a large xenolith underlain by mafics, after being detached from the Dennilton Dome during the intrusion event. Evidence generated by this study unequivocally indicate that the potential for viable PGE's, Ni, Cu and Au within a Merensky Reef- type configuration or a Plat Reef-type scenario under a relatively thin veneer of acid Bushveld Complex roof-rocks on the eastern flank of the Dennilton Dome, appears feasible.
  • Full Text:
  • Date Issued: 1996

The implications of the IMF programme in Zambia: lessons for South Africa in the Reconstruction and Development Programme (RDP)

  • Authors: Motsilili, Phoka
  • Date: 1996
  • Subjects: International Monetary Fund , Reconstruction and Development Programme (South Africa) , Social service -- South Africa , Economic assistance -- South Africa , Zambia -- Economic conditions -- 1964-
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2811 , http://hdl.handle.net/10962/d1003021 , International Monetary Fund , Reconstruction and Development Programme (South Africa) , Social service -- South Africa , Economic assistance -- South Africa , Zambia -- Economic conditions -- 1964-
  • Description: This study attempts to present a comparative analysis of the implication of the IMF in Zambia and South Africa in its Reconstruction and Development Programme (RDP). In examining the IMF programme, the study focuses on the Fund's understanding of such economies and its prescriptions for development. It is argued that IMF's familiar orthodoxy will have disastrous consequences for South Africa's poor, disadvantaged and rural communities. Finally, the IMF's market-oriented policy prescriptions are likely to erode democracy and have devastating effects to people-centred development programmes such as the RDP.
  • Full Text:
  • Date Issued: 1996
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