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Belethe

- Group performance, Group Composition, Dargie, Dave

Belethe

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

Bells and bellfounders of the Eastern Cape, South Africa

- Lewis, Colin A

  • Authors: Lewis, Colin A
  • Date: 1997
  • Language: English
  • Type: Article
  • Identifier: vital:6179 , http://hdl.handle.net/10962/d1012372 , http://www.ringingworld.co.uk
  • Description: [From Introduction] Although there is only one ring of bells in the whole of the Eastern Cape almost every church, and many chapels, have one or more bells. No systematic study of these bells had yet been made, but cursory examination suggests that many British founders exported bells to that area in the late 19th century and in the 20th century. American founders of steel bells also peddled their wares with considerable success. The Irish bell founder: Matthew O'Byrne sold at least five bells to clients in the Eastern Cape, the largest of which weighed 16 cwts. In the 1950s the Swiss founder, Ruetschi, of Aarau, cast at least four beautiful bells that are now in the Transkei. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
  • Full Text:
  • Date Issued: 1997

BI-Annual National Conference - Fisheries Policy and Response to White Paper

- Food and Allied Workers Union (FAWU)

  • Authors: Food and Allied Workers Union (FAWU)
  • Date: 1997
  • Subjects: COSATU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/110077 , vital:33221
  • Description: This paper is intended to serve as an aid to discussion in the Commission dealing with Sea Fisheries. Accordingly, its various sections provide an overview of the key issues which can inform discussion. Historically, access to marine resources was unrestricted. In order to facilitate the monopolisation of the fishing resource by a few white companies, a system of quotas was introduced. In this way many black fisher folk lost the access rights they had had for generations. At the present time, the fishing industry is completely biased in favour of a few large and medium sized white companies. This is illustrated by the fact that just three (3) companies hold;72% of the hake quota ;75% of the abalone quota , and 71 % of the sole quota. Overall , across all species, approximately nine tenths (9/10) of the resource is controlled by a hand-full of companies. Since 1994, some of these companies have attempted to blacken their faces. They have also sold minority shares to some, black business consortia. Further, a few members of the black elite have been given quotas. None of the above amounts to any kind of restructuring. None of the historic imbalances have been addressed. The above have merely been attempts to confuse the issue and to frustrate any process that attempts to restructure the industry. Prior to, and after the 1994 election, there were various initiatives by Alliance members to outline an equitable and just policy of reconstruction and development for the fishing industry.
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  • Date Issued: 1997

Bioaccumulation of heavy metals by the yeast S. cerevisiae and the bioremediation of industrial waste water

- Stoll, Anita

  • Authors: Stoll, Anita
  • Date: 1997
  • Subjects: Saccharomyces cerevisiae Yeast fungi -- Biotechnology Metal ions Bioremediation Water -- Purification -- Biological treatment
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4015 , http://hdl.handle.net/10962/d1004075
  • Description: Water is an essential element in all aspects of life and is vital for both domestic and industrial purposes regarding both the quality and quantity thereof. Similar to many other drought stricken countries, South Africa requires water for the socio-economic growth of the country, yet is faced with the problem of maintaining the quality of its drinking water as well as protecting the dwindling supplies. In an attempt to prevent the deterioration of South African water supplies the treatment, purification and recycling of industrial and mining waste water has recently become of prime importance. Many industrial and mining waste waters contain heavy metals in toxic quantities. The conventional processes that have been used till recently to address this problem, are often expensive or contain chemical agents which compound the environmental problem. As an alternative biological methods of metal accumulation appear to offer an economic and efficient alternative to these methods. An advantage to the South African scenario is the commercial production of the yeast, S. cerevisiae as a readily inexpensive by-product from some fermentation industries, Yeast cells, and in particular S. cerevisiae have proven to be capable of accumulating heavy metals, and therefore exhibit potential application in the bioremediation of waste water. The aim of this project was twofold. The initial part of this work attempted to define the mechanisms of metal accumulation by the yeast cells and cellular components. The information obtained from these initial studies provided a data base required for the development of a bioremediation system. Initial contact with the metal ions occurs at the wall interface of the yeast cell. Metal accumulation appears to be a function of all the cell wall components. The isolated cell wall components are better metal chelators then the intact cell walls. An apparent affinity series of mannan > chitin> glucan > intact cell walls exists. However, these components differ in their affinities for metal ions. Storage of metal ions within the cell occurs predominantly in the vacuole. The present study concluded that metal accumulation by the vacuole could be related to size. Metal accumulation occurred in the order of Cu2+ > Co2+ > Cd2+ with a corresponding decrease in atomic radii of Cd2+ > C02+ > Cu2+. Vacuolar ion deposition occurs at an early stage during the internalization of metal ions within the yeast cells. At the onset of vacuolar saturation, depositions of metal ions as granules within the cytosol occurs. In the presence of heavy metal cations viable yeast cells can be shown to exhibit two types of cellular responses. Uptake of Cu2+ and Cd2+ causes the loss of intracellular physiological cations from within the yeast cell. In comparison, uptake of Co2+ into the cell does not have this effect. All three heavy metal cations initiate plasma cell membrane permeability, thus the Cu2+ and Cd2+ induced loss of the intracellular cations, occurs. ~ a result of ion-exchange mechanisms and not due to cation leakage brought about by membrane permeabilization. Uptake of heavy metals by viable yeasts appears to be generally non-selective though the amount of metals accumulated are largely affected by the ratio of ambient metal concentration to biomass quantity. In addition, the energy dependent nature of internalization necessitates the availability of an external energy source for metal uptake by viable yeast cells. For these reasons metal removal from industrial waste water was investigated using non-viable biomass. By immobilizing the yeast cells additional mechanical integrity and stability was conferred apon the biomass. The three types of biomass preparations developed in this study, viz. polyvinyl alcohol (PV A) Na-alginate, PV A Na-orthophosphate and alkali treated polyethylenimine (PEI):glutaraldehyde (GA) biomass pellets, all fulfilled the necessary physical requirements. However, the superior metal accumulating properties of the PEI:GA biomass determined its selection as a biosorbent for bioremediation purposes. Biosorption of heavy metals by PEI:GA biomass is of a competitive nature, with the amount of metal accumulated influenced by the availability of the metal ions. This availability is largely determined by the solution pH. At low pH values the affinity of the biomass for metals decreases, whilst enhanced metal biosorption occurs at higher pHs, ego pH 4.5 - 6.0. PEI:GA biomass pellets can be implemented -as a biosorbent for the bi9remediaiton of high concentration, low-volume metal containing industrial waste. Several options regarding the bioremediation system are available. Depending on the concentration of the metals in the effluent, the bioremediation process can either be used independently or as part of a biphasic remediation system for the treatment of waste water. Initial phase chemical modification may be required, whilst two types of biological systems can be implemented as 'part of the second phase. The PEI:GA biomass can either be contained within continuous-flow fixed bed tanks or continuous-flow stirred bioreactor tanks. Due to the simplicity of the process and the ease with which scale-up is facilitated, the second type of system shows greater application potential for the treatment of this type of industrial waste water than the fixed-bed systems.
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  • Date Issued: 1997

Biologically active natural products from South African marine invertebrates

- Hooper, Gregory John

  • Authors: Hooper, Gregory John
  • Date: 1997
  • Subjects: Natural products -- South Africa Marine metabolites -- South Africa Marine invertebrates -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3761 , http://hdl.handle.net/10962/d1003239
  • Description: This thesis describes the chemical and biological investigation of the extracts of six different marine invertebrate organisms collected along the South African coastline. The work on these extracts has resulted in the isolation and structural elucidation of twenty-one previously undescribed secondary metabolites; The history of marine natural product chemistry in South Africa has not previously been reviewed and so a comprehensive review covering the literature from the 1940's up until the end of 1995 is presented here. The marine ascidian Pseudodistoma species collected in the Tsitsikamma Marine Reserve was shown to contain four new unsaturated amino alcohols [47], [48], [49] and [50] which were isolated as their acetyl derivatives. These compounds exhibited strong antimicrobial activity. Four new pyrroloiminoquinone alkaloids, the tsitsikammamines A [90] to D [93],were isolated from a new genus of Latrunculid sponge collected in the Tsitsikamma Marine Reserve. These highly pigmented compounds also possessed strong antimicrobial activity. An investigation of two phenotypic colour variants of the soft coral Capnella thyrsoidea resulted in the isolation of the known steroid 5α-pregna-1, 20-dien-3-one [97] and an additional six new metabolites, 16β-hydroxy-5α-pregna-1 ,20-dien-3-one 16-acetate [98], 3α,16β-dihydroxy-5α-pregna-1, 20-diene 3,16-diacetate [99] and four xenicane diterpenes, the tsitsixenicins A [100] to D [103]. This is the first reported isolation of xenicane diterpenes from the soft coral family Nephtheiidae. Tsitsixenicin A and B showed good anti-inflammatory activity by inhibiting superoxide production in both rabbit and human cell neutrophils. A further four new metabolites were isolated from two soft corals which could only be identified to the genus level and were designated Alcyonium species A and species B. Alcyonium species A was collected in the Tsitsikamma Marine Reserve and yielded two new polyhydroxysterols, cholest-5-ene-3β, 7β, 19-triol 19-acetate [121] and cholest-5,24-diene-3β, 7β, 19-triol 19-acetate [122]. The soft coral Alcyonium species B was collected off Aliwal Shoal and was found to contain two known xenicane diterpenes, 9-deacetoxy-14, 15-deepoxyxeniculin [110] and zahavin A [16], and two new xenicane diterpenes, 7 -epoxyzahavin A [123] and xeniolide C [124]. Compounds [110], [16] and [123] exhibited strong anti-inflammatory activity and compounds [110] and [16] showed good antithrombotic activity. The endemic soft coral A/cyanium fauri collected at Riet Point near Port Alfred yielded the new sesquiterpene hydroquinone rietone [141] in high yierd, fogether with the minor compounds 8'-acetoxyrietone [142] and 8'-desoxyrietone [143]. Rietone exhibited moderate activity in the NCl's in-vitro anti-HIV bioassays.
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  • Date Issued: 1997

Book Review: 1001 activities in environmental education

- Janse van Rensberg, Eureta

  • Authors: Janse van Rensberg, Eureta
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/438683 , vital:73490 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/137449"
  • Description: Book Title. 1001 activities in environmental educa-tion (1997). Book Author. Nico Allers. Publisher. Kamel eon Publishers, Vereeniging
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  • Date Issued: 1997

Breaking the karmic complex: the role of transpersonal phenomena in psychotherapy with an adult survivor of child abuse : a clinical case study

- Oberholzer, Sofia Adriana

  • Authors: Oberholzer, Sofia Adriana
  • Date: 1997
  • Subjects: Transpersonal psychology Reincarnation Adult child abuse victims -- Treatment
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3034 , http://hdl.handle.net/10962/d1002543
  • Description: This longitudinal study addresses the interface between the emerging paradigm of Transpersonal Psychology, which recognizes the transbiographical domain of consciousness, and the clinical area of child abuse. By using the transpersonal concept of the karmic complex, which was developed in the discourse of Roger Woolger, it explores the clinical value of past-life regressions and other transpersonal phenomena in the therapeutic process. The study provides an in-depth phenomenological description and a theoreticalheuristic explication of the experience of a single subject who was an adult survivor of physical and sexual abuse as well as early emotional deprivation in childhood, and who, over a four-year period of intensive psychotherapy, experienced a wide spectrum of transpersonal phenomena which included 123 past-life regressions. The therapeutic process could be clearly delineated into a biographical phase, which was dominated by biographical traumas, and a subsequ~nt transpersonal phase, during which the focus was almost exclusively on transpersonal material. This provided the opportunity to explore the therapeutic impact of trans personal mechanisms" of healing on an interlocking constellation of complexes in terms of achieving an integration of archetypal opposites in the psyche. The study provides strong support for transpersonal concepts about the nature of consciousness, as developed by Grof and Woolger. It affirms spirituality as an intrinsic property of the psyche, and verifies that the healing of psychological trauma is on a continuum with the process of spiritual purification and growth. The ,study establishes support for the clinical value of the karmic complex as a conceptual tool and provides a systematic, extended analysis of the multi levelled processes involved in the breaking of the complex.
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  • Date Issued: 1997

Catalytic behavior of osmium (II), rhodium (III) and ruthenium (II) Phthalocyanines towards the electrooxidation of cysteine on glassy carbon electrodes

- Sekota, Mantoa, Nyokong, Tebello

  • Authors: Sekota, Mantoa , Nyokong, Tebello
  • Date: 1997
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/293290 , vital:57072 , xlink:href=" https://doi.org/10.1002/elan.1140091608"
  • Description: Glassy carbon electrodes (GCE's) modified with phthalocyanine complexes of Rh, Ru and Os are employed for the catalytic oxidation of cysteine. When cyanide and dimethylsulfoxide (DMSO) are used as axial ligands giving (DMSO)(Cl)RhIIIPc, [(CN)2RhIIIPc]−, (DMSO)2OsPcII, and [(DMSO)2Ru(II)Pc]·2DMSO complexes, the peak currents for the oxidation of cysteine increase after each scan, indicating an increase in the catalytic activity of the electrode with repetitive scanning. This improvement in the catalytic activity of the GCE after the first scan is attributed to the formation of dimeric π cation radical species at the electrode surface.
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  • Date Issued: 1997

Cengeletshani

- Hogsback festival participants, Souma, N, Dargie, Dave

Chemical studies of necic acid analogues

- Guthrie-Strachan, Jeffry James

  • Authors: Guthrie-Strachan, Jeffry James
  • Date: 1997
  • Subjects: Organic acids , Chemistry, Organic
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4425 , http://hdl.handle.net/10962/d1006909 , Organic acids , Chemistry, Organic
  • Description: Various aldehydes have been reacted with methyl acrylate under Baylis-Hillman conditions, using DABCO as a catalyst, to afford a range of α-substituted acrylic esters containing an allylic hydroxy group. Selected Baylis-Hillman products have been brominated, hydrolysed and acetylated to afford substrates for the synthesis of necic acid analogues. The diastereo- and regioselectivity of nucleophilic attack, using sodium methylmercaptan, on the Baylis-Hillman products and selected brominated derivatives was investigated. The allylic hydroxy compounds favour conjugate addition with the generation of a new chiral centre, while the allylic bromo derivatives favour substitution (SN and SN') (S[subscript N] and S[subscript N]') with consequent loss of chirality. (E)-2-Isopropylcrotonic acid, a vital precursor in the synthesis of all stereoisomers of trachelanthic and viridifloric acid, was synthesised in an attempt to obtain the necic acid components required for total alkaloid synthesis of lycopsamine and its derivatives. This precursor and salicylic acid were then used to prepare esters of retronecine, a dihydroxy necine base obtained via extraction and consequent hydrolysis of retrorsine.
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  • Date Issued: 1997

Comparative ultrastructure of plasmodesmata of Chara and selected bryophytes: towards an elucidation of the evolutionary origin of plant plasmodesmata

- Cook, Martha E, Graham, Linda E, Botha, Christiaan E J, Lavin, Colleen A

  • Authors: Cook, Martha E , Graham, Linda E , Botha, Christiaan E J , Lavin, Colleen A
  • Date: 1997
  • Language: English
  • Type: Article
  • Identifier: vital:6506 , http://hdl.handle.net/10962/d1005933 , http://www.amjbot.org/cgi/reprint/84/9/1169
  • Description: We have used transmission electron microscopy to examine plasmodesmata of the charophycean green alga Chara zeylanica, and of the putatively early divergent bryophytes Monoclea gottschei (liverwort), Notothylas orbicularis (hornwort), and Sphagnum fimbriatum (moss), in an attempt to learn when seed plant plasmodesmata may have originated. The three bryophytes examined have desmotubules. In addition, Monoclea was found to have branched plasmodesmata, and plasmodesmata of Sphagnum displayed densely staining regions around the neck region, as well as ring-like wall specializations. In Chara, longitudinal sections revealed endoplasmic reticulum (ER) that sometimes appeared to be associated with plasmodesmata, but this was rare, despite abundant ER at the cell periphery. Across all three fixation methods, cross-sectional views showed an internal central structure, which in some cases appeared to be connected to the plasma membrane via spoke-like structures. Plasmodesmata were present even in the incompletely formed reticulum of forming cell plates, from which we conclude that primary plasmodesmata are formed at cytokinesis in Chara zeylanica. Based on these results it appears that plasmodesmata of Chara may be less specialized than those of seed plants, and that complex plasmodesmata probably evolved in the ancestor of land plants before extant lineages of bryophytes diverged.
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  • Date Issued: 1997

Contemporary experiences of the Buddhist mediation practice: a case-study approach

- Ravgee, Champavati Lala

  • Authors: Ravgee, Champavati Lala
  • Date: 1997
  • Subjects: Meditation -- Buddhism -- Case studies
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3156 , http://hdl.handle.net/10962/d1007549 , Meditation -- Buddhism -- Case studies
  • Description: The concern of this investigation is to explore a range of contemporary experiences of the Buddhist Meditation Practice of three South Africans of Western origin and to understand what factors were involved in their meditation practice. The number of people practising Buddhist Meditation in this country is gradually increasing and retreat centres for the meditation practice are emerging at various places in this country. A wide range of experiences accompany the meditation practice but very little research has been done amongst adults to study this phenomenon. Initially, in this study, the researcher practised Buddhist Meditation by participating in a meditation programme at the Buddhist Retreat in Ixopo in KwaZulu-Natal, for twenty-one days, to familiarize herself with the experiential knowledge of Buddhist Meditation. This was done by the researcher compiling a detailed diary of the meditative experiences and various themes were drawn from it. The data collected was compared and validated with contemporary research findings on Buddhist Meditation. This data was then used to formulate some of the questions for the semi-structured interviews that were conducted subsequently. Three adult subjects of Western origin, one male and two females were interviewed. Each subject had been meditating for an average period of ten years and can therefore be regarded as long-term meditators. They had practised Buddhist meditation in groups at various retreat centres around the country and also individually at home. The average age of the subjects was forty-five years, with the youngest subject being forty years old and the oldest being fifty-three years old. All three subjects were professional people employed at a university in South Africa and all were able to articulate their meditative experiences very well. Since the research project involved the study and exploration of the human experience related to Buddhist Meditation, it was more appropriate to use the phenomenological case-study approach rather than a measurement orientated procedure. The descriptive, phenomenological perspective is more appropriate for the elucidation of the data collected. It gives greater and clearer meaning to the human experience of meditation that is being investigated. The results of the study can best be summarised by stating that all three subjects undertook the Buddhist Meditation Practice because of their awareness of an existential conflict in their lives. Another reason for practising meditation was for personal development. The study also shows that a variety of effects of the meditation practice was experienced by the subjects. These included experiencing feelings of calmness, peace and relaxation, transformation of consciousness, heightened or increased awareness of certain external and internal stimuli, conscious of the changing nature of experience and experiences of objective consciousness.
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  • Date Issued: 1997

Corporate taxes and the taxation of dividends

- Williams, John Mark

  • Authors: Williams, John Mark
  • Date: 1997
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:890 , http://hdl.handle.net/10962/d1001644
  • Description: The classical system of taxation, whereby companies are taxed without a deduction for dividends paid and shareholders are taxed on their dividend receipts, results in double taxation of dividends. Split rate and imputation systems have been developed in an attempt to mitigate the effects of double taxation of dividends. Double taxation of dividends and differences between corporate and maximum individual marginal tax rates result in corporate tax systems lacking neutrality. Distortions arise between organisational forms, between debt and equity financing and between the retention and distribution of profits. Various methods of integrating corporate and individual taxes have been advocated to overcome the lack of neutrality caused by corporate taxes. Following the introduction of the South African Income Tax Act in 1914, a number of taxes relating to dividends have existed. These have included a Dividend Tax, Non-resident Shareholder's Tax, Undistributed Profits Tax and Secondary Tax on Companies, hereafter referred to as STC. STC is a tax on net dividends declared and results in distributed income being taxed at higher rates than retained income. Despite the implementation of group relief provisions, STC results in an inhibition on the reinvestment of profits within the context of a group of companies. It is also a major cause of the lack of neutrality of the South African corporate tax system. As a result of the lack of neutrality and inhibition of group reinvestment caused by STC, a full imputation system is suggested as an alternative to replace STC.
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  • Date Issued: 1997

Cytogenetic studies of Pseudobarbus and selected Barbus (Pisces: Cyprinidae) of southern Africa

- Naran, Daksha

  • Authors: Naran, Daksha
  • Date: 1997
  • Subjects: Cyprinidae
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5252 , http://hdl.handle.net/10962/d1005095 , Cyprinidae
  • Description: The aim of this study was to explore the karyology of temperate southern African barbine species in order to determine the extent and significance of polyploidy within the species. The study presents an optimised in vivo karyological protocol for the small barbines. The analysis of chromosomal data was explored using two approaches; measured (quantitative) and visual (qualitative). The karyology of 16 species of Barbus and six species of Pseudobarbus (Pisces: Cyprinidae) is reported. The study represents an almost complete (22/23 species) karyological survey of the temperate barbines. Chromosome number, arm numbers (NF) are recorded and karyotype morphology described for all species. Nucleolar organiser regions (NOR)s of 18 species have been examined by silver staining. Seven different AgNOR phenotypes occur among the species examined. Chromosome complements of the different species indicate at least three ploidy levels; diploid, tetraploid and hexaploid. Higher ploidy levels are represented in 78% (18/23) of species within the temperate fauna. This finding is remarkable, in the light of global proportions of cyprinid karyotypes, and provides an opportunity to shed further light on the evolution of polyploidy in barbine cyprinids. Results show that morphologically defined species complexes have distinct karyotypes, and most probably form cohesive phyletic clades. A phylogenetic tree was constructed using traditional morphological characters and tested against karyological data. The results suggests that similar ploidy states do not necessarily indicate close relationship between species. This supports a hypothesis of polyphyly for the African barbine cyprinids and also provides independent support for species complexes such as the "chubbyhead barb group" and the Pseudobarbus lineage. The broader implications of karyological findings are discussed within the context of African barbines and recommendations for further cytogenetic research are provided.
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  • Date Issued: 1997

Debate on globalisation

- COSATU

  • Authors: COSATU
  • Date: 1997
  • Subjects: COSATU
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/172083 , vital:42156
  • Description: At the Cosatu National Congress, a debate around the issue of globalisation erupted. At the core of the debate was whether the federation was opposed to globalisation or not. Some unions fell that as a federation we should be opposed to globalisation and all what it represents. Others felt that we should be opposed not to globalisation but its negative effects or the current form of globalisation.
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  • Date Issued: 1997

Dennett's compatibilism considered

- Puttergill, Julian Gatenby

  • Authors: Puttergill, Julian Gatenby
  • Date: 1997
  • Subjects: Dennett, Daniel Clement , Intentionality (Philosophy)
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2718 , http://hdl.handle.net/10962/d1002848 , Dennett, Daniel Clement , Intentionality (Philosophy)
  • Description: My basic concern in this thesis is to examine the details behind Dennett's attempt to reconcile the notions of mechanism and responsibility. In the main this involves an examination of how he tries to secure a compatibilism between mechanistic and intentional explanations by developing a systematised conception of intentional explanation. I begin by briefly discussing the various notions needed for understanding what is at stake in the area and where the orthodoxy on the matter lies. As such the first three sections of the work are not focussed on Dennett's work itself and playa stage-setting role for the deeper work to follow. These notions include the likes of the rationale behind attributing moral responsibility, agency and action, mechanism and mechanistic explanation, and intentional explanation. I suggest that the basic intuition regarding mechanism and responsibility is such that the two are seen to be incompatible with each other. The main reason for this lies in an intuition that mechanism undermines intentional explanation and so renders the notion of action largely empty. Action, I show, is at the heart of our attribution of responsibility and is dependent on intentional explanation. Having presented these issues, I turn to the details of Dennett's 'intentional systems theory'. I argue that Dennett attempts to avoid the intuition that mechanism is incompatible with responsibility by developing a specialised account of intentional explanation. Dennett calls it the intentional stance. r highlight the two important features of this intentional stance, namely rationality and intentionality. r show that Dennett's position on rationality and intentionality is such that it does allow him to secure an explanatory compatibilism between mechanism and his sort of intentional explanation. I argue, however, that his sort of intentional explanation does not fulfil our requirements for ascribing agency or moral responsibility. This is accomplished in part by developing alternative conceptions of the two notions. Out of this I develop a different sort of intentional stance, which I call the folk stance. I show finaIly that Dennett's compatibilist move is incapable of being applied to the folkstance from which we do in fact make attributions of responsibility, and so conclude thatDennett fails to make the case for reconciling mechanism and responsibility.
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  • Date Issued: 1997

Design, synthesis and evaluation of novel, metal complexing agents

- Hagemann, Justin Philip

  • Authors: Hagemann, Justin Philip
  • Date: 1997
  • Subjects: Ligands Metal complexes
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4307 , http://hdl.handle.net/10962/d1004965
  • Description: Various chelating ligands have been designed and synthesised; these include amino-amide ligands, tetraacetic acid systems and sulfur-containing amide ligands. Difficulties in the synthesis and purification of the amino-amide ligands were largely overcome, permitting the mono acylation of ethylenediamine and the synthesis of bis(2-aminoethyl)-2-benzylpropanediamide. Novel tetraacetic acid ligands, based on the propanediamide backbone and targeted as EDTA analogues, were obtained from their methyl and benzyl esters; but the instability of the tetraacids prevented their full characterisation. Bidentate, tridentate and tetradentate sulfur-containing monoamide ligands, based on the ortho-thio acetanilide moiety, were designed to specifically chelate platinum and palladium in the presence of base metals. In their synthesis, thiocyanation was used to introduce the orth-thio group on para-substituted anilines, and further functionalisation was achieved via appropriate protection of nucleophilic sulfur moieties. A range of tetradentate, sulfur-containing diamide ligands was also synthesised by reacting substituted 2-mercaptoacetanilides with 1,2- dibromoethane. Novel ligands were characterised by spectroscopic (¹H and ¹³C NMR; IR and M S) techniques and elemental (combustion and high resolution MS) analysis. Computer modelling and ¹H NMR chemical shift data have been used to explore the conformational preferences of the sulfur-containing acetanilide ligands. The macrocyclic ligands and systems with ortho-methylthio substituents appear to exhibit the greatest degree of coplanarity of the aromatic and amide functions. Solvent extraction studies revealed that the sulfur-containing amide ligands selectively extracted palladium(II) from platinum(II), copper(II}, nickel(II} and cobalt(II}. Even though the palladium(II} was extracted from an acidic medium, certain monoamide ligands were able to complex palladium(II) through their sulfur and deprotonated amide nitrogen donors, a trithia monoamide ligand being observed to displace all the chloride ligands on palladium to form a monomeric tetracoordinate complex. The diamide ligands, however, appeared to favour extraction of palladium(II) by coordination through their sulfur donors, forming 5-membered sulfur-sulfur chelates. In basic media (pH 8-9), selected sulfur-containing monoamide and diamide ligands have been shown to complex platinum(II) and palladium(II) through their sulfur and deprotonated amide nitrogen donors. At neutral pH, a dimercapto monoamide ligand has been shown to complex platinum from cisplatin with partial expulsion of the ammine ligands, while a macrocyclic trithia monoamide ligand has been observed to complex platinum from tetrachloroplatinate with concomitant deprotonation of the amide nitrogen. Where possible, the complexes were characterised by infrared and ¹H NMR spectroscopy and have also been studied using the computer modelling soft-ware programmes, Momec® and Hyperchem®.
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  • Date Issued: 1997

Detached harmonies : a study in/on developing social processes of environmental education in eastern southern Africa

- O'Donoghue, Rob B

  • Authors: O'Donoghue, Rob B
  • Date: 1997
  • Subjects: Environmental education -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:1939 , http://hdl.handle.net/10962/d1007726
  • Description: Long-term social processes are explored to examine the shaping of environmental education in eastern southern Africa. The study opens with early Nguni social figurations when 'to conserve was to hunt.' It then examines colonial conservation on the frontiers of imperial expansion and developing struggles for and against wildlife preservation. These processes shaped an inversion of earlier harmonies as declining wildlife was protected in island sanctuaries of natural wilderness and 'to conserve was not to hunt.' Inside protected areas, conservation management struggles shaped new harmonies of interdependence in nature, enabling better steering choices in developing conservation science institutions. Here more reality congruent knowledge also revealed escalating risk which was linked to a lack of awareness amongst communities of 'others' outside. Within continuing conservation struggles, education in, about and for the environment emerged as new institutional processes of social control. The study examines wilderness experience, interpretation, extension, conservancies and the development of an environmental education field centre, a teacher education programme and a school curriculum. Naming and clarifying the emergent education game for reshaping the awareness and behaviour of others is examined within a developing figuration of environmental education specialists. Particular attention is given to academic and statutory processes shaping environmental education as a field of objective principles and rational processes within modernist continuities and discontinuities into the 1990's. An environmental education field centre, an earth-love curriculum and research on reserve neighbour interaction are examined as political sociologies developing within a declining power gradient and wide ranging socio-political change. Into the present, a final window on a local case of water pollution examines shifting relational dynamics revealing how environment and development education models of process may have little resonance amidst long-term socio-historical struggles and shifting controls over surroundings, others and self. A concluding review suggests that grounded critical processes engaging somewhat blind control over surroundings may yet reshape self-control and social control amongst others. The trajectories of these clarifying struggles must remain open-ended as sedimented myth and memory is reshaped within ongoing processes of escalating risk and global intermeshing.
  • Full Text:
  • Date Issued: 1997

Determination of the optimum environmental requirements of juvenile marine fish : the development of a protocol

- Deacon, Neil

  • Authors: Deacon, Neil
  • Date: 1997
  • Subjects: Mariculture Fishes -- Ecology Grunts (Fishes) -- Ecology Pomadasys -- Ecology
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5254 , http://hdl.handle.net/10962/d1005097
  • Description: The spotted grunter, Pomodasys commersonnii, has been identified as a candidate species for mariculture in South Africa due to its high market demand and apparent biological suitability for culture. In common with most other potential mariculture species the spotted grunter has an estuarine juvenile phase. In this respect, the difficulties encountered in determining the optimum environmental requirements of spotted grunter are applicable to the majority of other potential mariculture species. Due the variability of estuarine habitats determination of the optimum environmental requirements of estuarine species under laboratory conditions are a prerequisite to subsequent evaluation of aquaculture potential. Therefore, using the spotted grunter as a representative of a typical potent ial mariculture species, the aim of this study was to contribute to the protocol for evaluating the environmental requirements of potential aquaculture species. The growth of fish is dependent on the relationship between food intake, metabolism and environmental factors. In this relationship, environmental factors do not act on growth per se, but rather act through metabolism on growth. Consequently, the environmental factors affecting the growth of a fish species can be classified into functional categories according to their respective influence on metabolic processes. Five functional categories are recognised, namely: controlling, limiting, masking, directive and lethal factors. In this study, the functional categories were sequenced to develop a theoretical protocol for determining the optimum environmental requirements of potential mariculture species under artificial conditions. It was hypothesised that the correct sequence for experimentally determining the optimum environmental requirements of a species should correspond to theoretical protocol. The hypothesis was tested from the experimental investigation into the individual effects of temperature, salinity, light intensity, photoperiod and food intake on growth performance of juvenile spotted grunter. The investigations quantified the relative effects of controlling, masking, directive and limiting factors on growth performance. The results of the studies were statistically compared to obtain a ranking of the effects of the environmental factors (e.g. temperature, salinity, etc.) on growth performance of juvenile spotted grunter. The statistical ranking facilitated the formulation of a second protocol for sequentially determining the optimum environmental requirements of a species. The second protocol was derived purely from the experimental data. Based on the corroboration between the theoretical protocol and that formulated from the experimental investigations, the hypothesis was accepted. Confirmation of the protocol for examining the effects of controlling, limiting, masking and directive factors provided a basis for the development of a preliminary experimental sequence for determining the optimum environmental requirements of juvenile marine fish. In the development of the experimental sequence, the protocol was interpreted in conjunction with the experimental methods used to determine the effects of environmental factors on the growth of juvenile spotted grunter. The experimental sequence provides a logical frame work within which the optimum environmental requirements of other marine fish species can be determined. In addition, evaluation of growth performance by this method provides a basis for comparison of the mariculture potential between species.
  • Full Text:
  • Date Issued: 1997
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