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Eyam' Indoda Iyazeka

- Nogcinile, Composer not specified, Dargie, Dave

F C Erasmus and the politics of South African defence, 1948-1959

- Boulter, Roger Stephen

  • Authors: Boulter, Roger Stephen
  • Date: 1998
  • Subjects: Erasmus, F C (Francois Christiaan) South Africa -- Politics and government -- 1948-1961 South Africa -- Armed Forces -- History South Africa -- Military policy
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2534 , http://hdl.handle.net/10962/d1002386
  • Description: FC Erasmus became South Africa's defence minister in 1948 after two decades as a leading political organiser for the National Party. Although an architect of the Nationalists' post-war election victory he was not considered a minister of the first rank. Erasmus initiated a process of ridding the defence force of officers who he believed were associated with the Smuts government and replacing them with party supporters. As a result the military often lost experienced and talented officers. Erasmus felt that the armed services had been too British in ethos and appearance. He inaugurated tighter regulations on bi-lingualism, reintroduced boer rank titles, launched new uniforms and original medals and decorations, to the acclaim of the volk. His purpose was to have a defence force which was uniquely South African. Many of his policies came under attack not only from the United Party but also groups such as the Torch Commando and the veterans organisations. With the apparent lack of an imminent military threat to the apartheid government Erasmus never received substantial budgetary allocations from finance ministers. The defence force, one without conscription, remained small with largely antiquated equipment for the important air and land forces. However by the decade's end the navy was gradually receiving modern ships under the terms of the Simonstown agreement, which Erasmus had negotiated with Britain. The events of the Sharpeville crisis, just after Erasmus left defence, demonstrated that the armed forces as moulded by the minister were in poor condition to assist the civil power in suppressing disturbances. Overseas Erasmus hoped to increase the acceptability of the Union as a defence partner among Western countries by providing personnel for the Berlin Air Lift and the Korean conflict and promising a contingent for the Middle East. He attempted unsuccessfully to instigate anti-communist alliances for the land and maritime defence of Africa when the European powers were leaving the continent. These actions were primarily to obtain political support for the Union, whose prestige was rapidly decreasing as apartheid became better known. The external initiatives with the exception of the Simonstown naval agreements were not lasting.
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  • Date Issued: 1998

Family diversity : a South African perspective focusing on Whites in Grahamstown

- Ziehl, Susan C

  • Authors: Ziehl, Susan C
  • Date: 1998
  • Subjects: Families -- History -- Research Families -- South Africa -- Grahamstown Families Families -- Research -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3341 , http://hdl.handle.net/10962/d1004467
  • Description: Drawing on developments in the field of family history and studies of families in contemporary settings, the study addresses the question of explaining variations in household patterns. Its empirical basis is a survey of White households in Grahamstown. The surveyed population was broken down in terms of class (occupation) and culture (language) and analyses conducted to determine if there are any statistically significant relationships between these variables and the tendency to reside in particular household structures. The question of 'family ideology' was also addressed as an attempt was made to uncover subjects' views on a variety of family-related issues. On the basis of the research results, a model of the relationship between class, culture and household structure was developed. Its application to a comparison of Black and White household structures in South Africa as well as the United States, is discussed. Finally, attempts at redefining the family are addressed and a new definition of the family proposed.
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  • Date Issued: 1998

Faso Den Kulu

- Kenza Batoma Diallo (author, composer, lead singer), Aliou Traore (violin), Benogo Diakite (ngoni, kangnan), Kabin Kaba Diakite (guitar, bass, yabara), Halima Sangare (chorus), Souleymane Dembele (balafon), Kalibou Diarra (djembe), MALI K7 S.A. Ali Furka Toure Associe, Bamako

Finding the optimum: fluoridation of potable water in South Africa

- Muller, Wilhelmine J, Heath, R G M, Villet, Martin H

  • Authors: Muller, Wilhelmine J , Heath, R G M , Villet, Martin H
  • Date: 1998
  • Subjects: Water SA
  • Language: English
  • Type: Article
  • Identifier: vital:6921 , http://hdl.handle.net/10962/d1011904
  • Description: Since the South African Department of Health has tabled legislation to make fluoridation of public water supplies mandatory, the issue of whether fluoride is beneficial or harmful has, once again, become controversial in South Africa. We reviewed the literature, the experiences of fluoridation in overseas countries and the latest WHO recommendations, and have found that fluoride is desirable at certain levels, and undesirable above these. The following recommendations are made for optimum fluoride levels in South Africa's potable water: The decision to fluoridate a public water supply must be a community decision taken after public consultation. However, it can only be reached when the public is properly informed about the issue. Optimum levels of fluoride for human health range from 0.4 to 0.7 mg F/l, depending on the maximum mean annual temperature. The maximum level of 0.7 mg F/l should not be exceeded. Accordingly, it is recommended that in areas where natural fluoride concentrations in the drinking water exceed 0.7 mg F/l steps be taken to defluoridate the water. As an interim measure, a scale of temperature-adjusted optimum fluoride levels should be adopted in South Africa, rather than a single level covering the wide-ranging ambient temperatures (and corresponding consumption rates of drinking water) in the country. A sliding scale would mean that the community within a water supply region can determine its own fluoride consumption within the optimum range. Fluoridation should be considered only a short-term measure, until economic conditions are such that all South Africans have access to proper dental health care. The duration of fluoridation of a community water supply, and the level of fluoridation (within the optimum range of fluoride levels) should both be considered community decision. However, defluoridation should be a permanent necessity in those areas where the drinking water exceeds levels of 0.7 mg F/l.
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  • Date Issued: 1998

Finite element modelling of magma convection and attendant groundwater flow

- Harrison, Keith

  • Authors: Harrison, Keith
  • Date: 1998
  • Subjects: Groundwater flow , Magmas
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5467 , http://hdl.handle.net/10962/d1005252 , Groundwater flow , Magmas
  • Description: This thesis describes preliminary two- and three-dimensional modelling of mass and heat transport of hot, molten magma in crustal intrusions and of the associated thermally induced flow of groundwater contained in the surrounding country rock. The aim of such modelling is to create a tool with which to predict the location of mineral deposits formed by the transport and subsequent precipitation of minerals dissolved in the convecting groundwater. The momentum equations (Navier-Stokes equations), continuity equation and energy equation are used in conjunction with specially constructed density and viscosity relationships to govern the mass and heat transport processes of magma and groundwater. Finite element methods are used to solve the equations numerically for some simple model geometries. These methods are implemented by a commercial computer software code which is manipulated with a control program constructed by the author for the purpose. The models are of simple two- or three-dimensional geometries which all have an enclosed magma chamber surrounded completely by a shell of country rock through which groundwater is free to move. Modelling begins immediately after the intrusive event when the magma (in most cases rhyolitic) is at its greatest temperature. Heat is allowed to flow from the magma into the country rock causing thermal convection of the groundwater contained therein. The effect of the country rock as a porous medium on the flow of groundwater is modelled by including a distributed resistance term in the momentum equation. The computer code that controls the modelling is such that adaptions made to the models to represent real physical intrusive systems are trivial. Results of the research at this stage allow approximate prediction of the location of mineral deposits. Enhanced predictions can be made by effecting improvements to the models such as a more detailed representation of chemical processes, adaption of the computer code to allow multiple injections of magma and the modelling of frozen magma as a porous medium which admits the flow of groundwater.
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  • Date Issued: 1998

Fluvial conditions during the Holocene as evidenced by alluvial sediments from above Howison's Poort, near Grahamstown, South Africa

- Lewis, Colin A, Illgner, Peter M

  • Authors: Lewis, Colin A , Illgner, Peter M
  • Date: 1998
  • Language: English
  • Type: Article
  • Identifier: vital:6697 , http://hdl.handle.net/10962/d1006733
  • Description: Mapping and analyses of alluvial sediments in the Berg River valley, near Grahamstown, has resulted in the identification of over 5 000 years of environmental stability in the early Holocene, in which flood plain sediments accumulated. Subsequent to 4390±90 BP environmental instability, probably due to climatic fluctuations, resulted in the formation of river terraces. Further research is needed to establish the area! limits of this sequence of Holocene climatic and environmental events.
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  • Date Issued: 1998

Foro bana

- Habib Koite (lead singer, guitar, chorus, lyrics, composer), Baba Sissoko (n'goni, balafon), Abdoul W. Berthe (bass guitar, kamale n'goni), Souleymane Ann (drums, calebasse, chorus), Boubacar Sidibe (guitar, chorus, harmonica), Fanga Diawara, Mahame Cisse, Alhousseini Dicko (violon peuls, Malian instrument ensemble), Coutre-Jour, Putumayo World Music

FOUNDATION COURSE FOR NEW UNION STAFF - Facilitators notes

- DITSELA

From confrontation to co-operation: new security challenges facing post-apartheid Southern Africa

- Monnakgotla, Kgomotso

  • Authors: Monnakgotla, Kgomotso
  • Date: 1998
  • Subjects: Economic security -- Africa, Southern , Cooperation -- Africa, Southern , Africa, Southern -- Economic policy , Africa, Southern -- Foreign relations
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2807 , http://hdl.handle.net/10962/d1003017 , Economic security -- Africa, Southern , Cooperation -- Africa, Southern , Africa, Southern -- Economic policy , Africa, Southern -- Foreign relations
  • Description: Trite as it may sound, the end of the Cold War is a landmark event in the history of human-kind. As such, this thesis was motivated by some of the international and local events that have taken place since the end of the 1980s. At the international level, the end of the Cold War has encouraged the re-examination of the concept of security. In Southern Africa too, this process has been strengthened by the demise of apartheid in South Africa. Initially challenged by a few academics, the traditional conception of security which perceived the threat to 'national' security primarily in the form of external military aggression no longer enjoys the primacy it was accorded during the Cold War era. A 'new' security discourse has emerged, and even though it has not yet made inroads into many governments' policy papers, there is some realisation that people's security concerns go beyond external military aggression to the state. Proponents of this 'new' thinking make reference to people-centred or human security - the notion that people and not the state, must be the objects of security. Arising from that, they point to the existence of many phenomena which should also be accorded security status especially in developing countries where people are confronted by life-threatening challenges such as disease, poverty, famine, and other challenges which do not necessarily threaten life, but if not tackled with urgency could transform themselves into the more conventional military threats. Here reference is made to the proliferation of small arms, political instability, mass migr?tions, and so on. In a region besotted by many of the challenges mentioned above, a security conception informed by the 'new' approach seems more appropriate. The outcome of the traditional approach to security is well known to the region many millions of lives were lost and it is estimated that billions of dollars in revenue were also lost, all in the name of maintaining the security of the South African state. Seeing neighbouring states as threats to its security because they accommodated liberation movements who occasionally instigated military attacks against Pretoria, the former apartheid state through its policy of 'Total Strategy' terrorised the entire region, including the majority of citizens within South Africa. However, since the end of apartheid in 1994, the new democratically elected South African government has committed itself to help build a politically stable, more secure, economically prosperous and integrated region. Through its accession to the Southern African Development Community (SADC), a body which it once tried to undermine, South Africa has further demonstrated a commitment to tackle some of the region's problems in unison with its former adversaries. Throughout the Southern African region there is a realisation that there are more long-term benefits to be gained by working together to tackle the challenges that confront almost all the countries in the region than trying to solve problems independently. Therefore through SADC, primarily a development-oriented body, Southern African states will also seek to address the region's security concerns. Many of the region's governments seem to show an understanding that security and development are intertwined - that they are two sides of the same coin whereby one cannot be attained without the other. Much as this understanding is laudable, in practice it does not seem as if it will translate to the prominence of so-called development issues or marginal security issues. Accepting the 'new' thinking on security also implies an acceptance of a wider range of security agents. It does not mean that by widening the agenda of security to include nonmilitary threats, more tasks will follow for the 'men' in uniform. What it means is that, the military establishment should no longer be the sole agent of security. Instead, where there is no military threat, resources should be channeled to other establishments such as those of health and research in order to fight the spread of AIDS. Furthermore, departments of water, environmental affairs, and so on, should be part of the security policy-making process. In addition, civil society should also be included in the policy-making process. Notwithstanding its limitations, and without undermining inter-governmental projects, civil society can at best promote security by serving as a watch-dog over policies adopted by governments. South Africa during the era of apartheid is a classic example of how governments cannot always be entrusted with the security of ordinary citizens. However, an examination of the structure and terms of reference of the newly created SADC Organ for Politics, Defence and Security (from henceforth referred to as the Organ) reflects a preponderance of the traditional/realist approach to addressing security concerns. It was conceived by, and is primarily constituted by the traditional establishments of security, that is, the military and the police. Some of the Organ's objectives include; security and defence cooperation through conflict prevention, management and resolution and mediation of disputes and conflicts. Nowhere is it evident that others besides those from a military/police background were involved in the formation of this important body. There is also no indication as to how other dimensions of security will be attained through the Organ. All this casts doubt regarding SADC's actual commitment to a development-oriented, people-centred and people-driven security. Nonetheless, current debates on security give hope to the notion that in the future, people's overall security needs will be addressed.
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  • Date Issued: 1998

From Sequencer to IP Packets-Routing MIDI Messages Over Longer Distances

- Foss, Richard

  • Authors: Foss, Richard
  • Date: 1998
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/427418 , vital:72437 , https://www.aes.org/e-lib/browse.cfm?elib=8476
  • Description: This paper describes the operation, and design of a MIDI-to-IP-to-MIDI router which overcomes the channel and distance limitations inherent in the MIDI protocol. It allows Windows-based programs and MIDI transmitters to route MIDI messages over long distances to MIDI receiving devices. Each networked PC in the system has one or more MIDI input/output ports. MIDI transmitters and receivers are connected to the input and output ports, respectively, and are given symbolic names. The system allows connections to be made between the transmitters and receivers.
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  • Date Issued: 1998

Genre analysis and the teaching of academic literacy: a case study of an academic discipline in the social sciences

- Vorwerk, Shane Paul

  • Authors: Vorwerk, Shane Paul
  • Date: 1998
  • Subjects: Lectures and lecturing , Lecture method in teaching , Language and culture , Discourse analysis , Language and culture -- South Africa , English language -- Discourse analysis , Intercultural communication -- South Africa , English language -- Study and teaching -- South Africa -- Foreign speakers
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2365 , http://hdl.handle.net/10962/d1002648 , Lectures and lecturing , Lecture method in teaching , Language and culture , Discourse analysis , Language and culture -- South Africa , English language -- Discourse analysis , Intercultural communication -- South Africa , English language -- Study and teaching -- South Africa -- Foreign speakers
  • Description: Students in tertiary educational institutions in South Africa come from many different backgrounds and have varied educational experiences. Some students, especially those from non-English speaking backgrounds, may encounter linguistic difficulties with various academic tasks. In order for students to be successful at university, they must become academically literate. That is, they must master all the reading, writing, listening and comprehension tasks required by the disciplines in which they are studying. One such task is presented by the academic lecture which is an integral part of any course of study. Linguistically, the academic lecture can be seen as a particular genre with unique characteristics. This study investigated some linguistic characteristics of academic lectures. The discipline of Political Science, as a Social Science, was chosen because there is little research that has been done on language in the Social Sciences. The Political Science sub-disciplines of Political Philosophy, South African Politics, and International Relations were used in this research. First year lectures were recorded from each of these three sub-disciplines. The linguistic characteristics of lectures were analysed using techniques drawn from Systemic Functional linguistic theory. The analysis concentrated on the aspects mode and field as they were realised in the lectures. In addition, higher level generic structure was also analysed. The insights gained from the analysis were validated through interviews with the lecturers who gave the lectures. The aim of this research was to develop a linguistic characterisation of the lecture genre as it occurs in the three sub-disciplines of Political Science. The results of this research suggest that although there is a unified academic lecture genre, there is variation according to sub-discipline. The implications of this variation are discussed with reference to their relevance to teaching academic literacy.
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  • Date Issued: 1998

Geochemical variations in a long Karoo dyke, Eastern Cape

- Marsh, Julian S, Mndaweni, M J

  • Authors: Marsh, Julian S , Mndaweni, M J
  • Date: 1998
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149715 , vital:38877 , https://hdl.handle.net/10520/EJC-1abee09c1f
  • Description: A prominent vertical dolerite dyke, up to 30 m wide and which can be traced for over 100 km, is compositionally homogeneous along much of its length and shows no evidence of flow differentiation. Associated parallel dykes are compositionally distinct and are unrelated by closed-system processes. The main dyke has geochemical characteristics of the Maloti or Senqu Units in the upper part of the main Lesotho basalt sequence, whereas the parallel dykes are geochemically similar to the lower Mafika Lisiu Unit. On the basis of size and composition the main dyke may well represent a fissure which once fed effusions of Karoo basalt.
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  • Date Issued: 1998

Good faith and procedural unfairness in contract: Eerste Nationale Bank van Suidelike Afrika Bpk v Saayman 1997 (4) SA 302 (A)

- Glover, Graham B

  • Authors: Glover, Graham B
  • Date: 1998
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/155975 , vital:39937 , https://heinonline.org/HOL/Page?collection=journalsamp;handle=hein.journals/tyromhldre61amp;id=358amp;men_tab=srchresults
  • Description: "It is unlikely that Bank of Lisbon will remain the last word on the matter of good faith and contract law" (Zimmermann "Good faith and equity" in Zimmermann and Visser (eds) Southern cross: Civil law and common law in South Africa (1996) 256). These words have proved to be prophetic in the light of the recent decision handed down by the Supreme Court of Appeal in Eerste Nasionale Bank van Suidelike Afrika Bpk v Saayman.
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  • Date Issued: 1998

Graphicacy as a form of communication in the primary school

- Wilmot, Pamela Dianne

  • Authors: Wilmot, Pamela Dianne
  • Date: 1998
  • Subjects: School children -- South Africa Visual communication Perception in children Visual literacy Pictures
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1551 , http://hdl.handle.net/10962/d1003433
  • Description: Children of today inhabit a multi-dimensional world, and in order to communicate effectively in it, they need the ability to utilise four forms of communication namely, oracy, literacy, numeracy and graphicacy. Communicating in graphic form requires an ability to both encode and decode spatial information using symbols, which requires the utilisation and application of spatial perceptual skills and concepts. The acquisition of graphic skills has been influenced by traditional developmental perspectives; increasingly the assumptions underpinning these have been challenged by more recent international research findings. The draft Curriculum Framework for General and Further Education and Training (1996: 18) identifies graphic literacy as one of the critical outcomes of the new South African curriculum. For graphic literacy to be an achievable outcome of the new curriculum, we need to investigate the skills and concepts underpinning this form of communication. The goal of this research is to investigate graphicacy as a form of communication in South African primary schools. However, given the scope of a research project of this nature, it was decided that rather than dealing with graphicacy per se, pictures as the most frequent and concrete type of graphic communication encountered by young learners would be focused on. In seeking to investigate pictures, the first stage of the study is concerned with diagnosing and illuminating children's graphic skill development through identifying: what skills they use; how they use and apply these when communicating through and interpreting symbols; and the difficulties they experience when, firstly, encoding spatial information through a series of practical and drawing tasks; and secondly, when reading and interpreting pictures. The second stage of the study investigates the extent to which children's early childhood experiences may or may not have impeded or enhanced the acquisition of skills necessary for understanding and communicating about space. The research findings, evaluated according to existing and emerging theoretical perspectives on graphicacy, will help to illuminate the current situation regarding the graphic literacy of South African primary school children. The study may contribute to wider international debates about graphicacy as a form of communication and the development of graphic literacy, from a South African perspective.
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  • Date Issued: 1998

Group problem solving among community activists in a South African setting: an everyday cognition approach

- Van Vlaenderen, Hilde

  • Authors: Van Vlaenderen, Hilde
  • Date: 1998
  • Subjects: Group problem solving Group problem solving -- South Africa Cross-cultural studies -- Methodology Cognition Cross-cultural studies Cognition -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3080 , http://hdl.handle.net/10962/d1002589
  • Description: The study focuses on the everyday problem solving processes of a group of community activists in a rural setting in the Eastern Cape Province of South Africa. It aims to uncover: first, the local knowledge of the participants of the study with reference to the concepts problem and problem solving; second, the participants' group problem solving procedure; and third, the dialectical interrelation between the participants' knowledge and practice with reference to everyday group problem solving. It is contended that the mainstream cognitive approach and the cross-cultural tradition are inappropriate for the study of everyday cognitive processes. A ‘situated cognition’ approach, based on the notions of activity and cultural mediation, is proposed as a theoretical framework for the study. The ontological and epistemological assumptions underpinning the empirical study were derived from a scientific realist and a hermeneutical paradigm. Data for the inquiry into the local knowledge of the participants was collected through individual interviews. The data was interpreted, using the grounded theory techniques of constant comparison, coding and compiling theoretical diagrams. Data for the inquiry into the participants' group problem solving practice consisted of video-taped group problem solving processes. This data was analysed, using a multi layered process of progressively deeper interpretation, employing a reading guide technique. Analysis of the research data revealed that the participants perceived a problem as an impediment to satisfactory participation in society. Problem solving was considered as an emotive, cognitive and inter-active process, involving particular role players. This process had a certain structure, involved attitudes and actions and relied on particular resources. Successful problem solving was perceived to result in restoration of social equilibrium. The group problem solving procedure used by the participants consisted of a process of developing a common understanding and group consensus. The strategies employed in the process, the roles played by the participants, the rules adhered to by the participants and the structure underlying the process were all congruent with these aims. There was a mutually reinforcing interrelation between knowledge and practice with reference to the participants’ problem solving.
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  • Date Issued: 1998

Growth, reproduction and feeding biology of Turbo sarmaticus (Mollusca : Vetigastropoda) along the coast of the Eastern Cape Province of South Africa

- Foster, Gregory George

  • Authors: Foster, Gregory George
  • Date: 1998
  • Subjects: Turbinidae -- Ecology -- Research -- South Africa Turbinidae -- Research -- South Africa Mollusks -- Research -- South Africa Abalones -- Ecology -- South Africa -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5705 , http://hdl.handle.net/10962/d1005391
  • Description: Investigations were carried out on aspects of the biology of the vetigastropod Turbo sarmaticus. Studies included: 1) the distribution and standing stock of this animal at four sites along the coast of the Eastern Cape Province of South Africa; 2) the growth rate of animals on a wave-cut platform; 3) the reproductive cycle of an intertidal population; and 4) aspects of the feeding biology examining the ability of this mollusc to consume and digest six macroalgae, the influence of algal diet on growth rate and reproductive fitness and the polysaccharolytic activity of the digestive enzymes. On eastern Cape shores, T. sarmaticus had a size related distribution, with smaller animals being found towards the upper mid-shore and larger animals being found in a downshore direction. The mean shore densities of T. sarmaticus at three sites where exploitation of animals was minimal, were very similar (1.2 - 1.7 individuals/m²). The largest animals (up to 110 mm shell length) were found on an offshore island. This may have been a result of animals not being exploited, as well as a possible increase in primary productivity and food availability. The lowest density (0.2 individuals/m²) and animal size (<70 mm shell length) was recorded at a site (Kelly's beach - Port Alfred) where exploitation was more intense. It is probable that intense overexploitation was threatening the populations at this site. The growth rate of T. sarmaticus was determined by means of the von Bertalanffy growth model and expressed by the equation L[subscript]t = 81.07(l-e⁻°·⁵⁴⁴[superscript](t)). The initial growth rate of T. sarmaticus (up to ≈ 80 mm shell length) was similar on shores with different geomorphologies (i.e. boulder shores and wave-cut platforms). Growth rates of individuals were variable, which means that individuals within a population reached exploitable size (3 - 6 years old) and sexual maturity (1.5 - 2 years old) at different ages. Seasonality of reproduction of T. sarmaticus was determined using gonad index, egg diameters and spermatozoa content within the gonad. Turbo sarmaticus was dioecious and had a sex ratio in favour of males (1.2: 1). Animals attained sexual maturity at a size of about 52.5 mm shell length. There was little variation in the reproductive cycle over time with gametogenesis occurring from March/April until August/September, whilst maturity (Gonad Index = 15%) was maintained until the spawning event from December to March. After spawning the gonad regressed. Field and laboratory observations of the feeding biology of T. sarmaticus confirmed that this mollusc was a generalist grazer capable of consuming and digesting algae from the Rhodophyta, Chlorophyta and Phaeophyta. The consumption rates (juveniles: 1.45 - 9.50% body weight/day, adults: 1.06 - 6.08%) and digestibility (9 - 75% apparent dry matter) of six macroalgae was found to vary. For most algae, juvenile T. sarmaticus had higher consumption rates (1.6 - 2.8 times higher) and digestibility values (12 - 24% higher) than adults. It is suggested that consumption rates were dependent on the digestibility of the algae. In addition, it is suggested that the consumption rates of the different algae were not related to the nutritional content, but rather the energetic content of the algae. In both juvenile and adult animals, temperature had a positive influence on consumption rates, resulting in an increase at higher temperatures. However, in both juvenile and adult T. sarmaticus, algal digestibility was not affected by temperature. Finally, it was proposed that Viva rigida, Codium extricatum, Ecklonia radiata and Gelidium pristoides would provide the best nutritional value for growth and reproductive fitness in T. sarmaticus, whilst Jyengaria stellata and Corallina spp. would provide the poorest. Experiments on the effects of four algal diets on the biology of T. sarmaticus showed that the best growth rate (up to 13.8 mm shell length increase per annum), reproductive fitness (Gonad Index up to 33%) and energy levels (up to 4.76% glycogen in the foot) were achieved when T. sarmaticus was fed G. pristoides, U. rigid a or a mixed diet. Turbo sarmaticus fed Corallina spp. showed reduced growth (2.4 mm shell length increase), reproductive fitness (Gonad Index up to 4.4%) and energy levels (up to 3.42% glycogen in the foot). A study of the polysaccharolytic enzyme activity of T. sarmaticus indicated that this mollusc possesses enzymes that can, at least partially, digest most of the storage and structural polysaccharides found in the Chlorophyta, Rhodophyta and Phaeophyta. This further supported the findings that T. sarmaticus was a generalist grazer. Two levels of activity were detected: 1) high levels of enzyme activity (up to 328.2 Ilglmglmllhr)occurred on the storage polysaccharides that occur in the Rhodophyta and Chlorophyta, and 2) lower levels of activity were detected on the storage polysaccharides (up to 44.8 μg/mg/ml/hr) of the Phaeophyta and on all the structural polysaccharides tested (<45.5 μg/mg/ml/hr). It was suggested that T. sarmaticus did not rely heavily on structural carbohydrates as a source of carbon. Finally, the results of this study were discussed in relation to the future management of T. sarmaticus stocks, the possible role of this macro algal grazer in the intertidal zone and the effects of over-exploitation of this animal. The potential aquaculture of this mollusc was also addressed briefly.
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  • Date Issued: 1998

HIV and metaphor: an imaginative response to illness

- Cardo, Julia Claire

  • Authors: Cardo, Julia Claire
  • Date: 1998
  • Subjects: HIV infections , Metaphor -- Psychological aspects , Imagery (Psychology) -- Therapeutic use
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2945 , http://hdl.handle.net/10962/d1002454 , HIV infections , Metaphor -- Psychological aspects , Imagery (Psychology) -- Therapeutic use
  • Description: The medical model has been criticised for its failure to attend to individuals' experience of illness and the meaning they attribute to illness. HIV / AIDS has challenged its adequacy and brought the question of meaning in illness into sharp focus. This study aimed to understand what it means to live with HIV by exploring the fantasies, images and metaphors that make up the depth of such an experience. Phenomenology was deemed the appropriate approach, as it assigns epistemological significance to metaphor and ontological primacy to the lifeworld. An interview guide was fashioned from existing phenomenological literature and in-depth interviews were conducted with eight HIV -infected individuals. Five protocols were selected to constitute the study. In addition, an audio tape recording of one individual's metaphorical dialogue with HIV was obtained and transcribed. The three protocols with the richest content of imagery and metaphor were subjected to phenomenological explication. The remaining two protocols were used to support and clarify emergent meaning. A phenomenological explication of the data revealed a number of salient metaphors and themes. Upon being diagnosed with HIV, individuals were confronted with a socially and institutionally prescribed understanding of the disease; HIV as synonymous with AIDS and immediate death, HIV as sexual deviance, and HIV as myth. These metaphors influenced their conceptualisation and handling of HIV. Individual embodied metaphors included: embodying a heart of stone to live with HIV and perceiving HIV as a punishment from God, a demon from the Devil, a death sentence and a torture. Affectively, the experience of HIV was constituted as fear of physical disfigurement and exposure, anxiety, vulnerability, anger, betrayal, injustice and isolation. In a process of resolution and transformation, individuals imbibed positive metaphors with which to continue living with HIV. In order to cope with HIV, individuals seemed to negotiate a metaphorical space in which to dwell with their virus. This entailed establishing some form of dialogue with HIV or a Higher Power. This study revealed that metaphorical thinking about HIV /AIDS has a powerful impact on individuals' embodiment of their world. Metaphor is also an effective means Clf conveying and eliciting meaning in the experience of illness. Based upon these findings, it was suggested that metaphor be a prime focus for future research endeavours.
  • Full Text:
  • Date Issued: 1998

Homogenous and heterogenous catalytic activity of metallophthalocyanines towards electrochemical detection of organic compounds

- Mafatle, Tsukutlane J P

  • Authors: Mafatle, Tsukutlane J P
  • Date: 1998
  • Subjects: Electrochemistry , Organic compounds , Phenols
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4316 , http://hdl.handle.net/10962/d1004974 , Electrochemistry , Organic compounds , Phenols
  • Description: Cysteine plays an important role in many biological and pharmaceutical systems. Therefore, in view of its importance, it is essential to find means of detecting it at the lowest possible levels. In this regard, electrochemical techniques have been found to be capable of detecting analytes even at micro levels. However, electrochemical determination of cysteine occurs at a very high potentials. These overpotentials makes quantitative analysis or detection of cysteine difficult at most conventional carbon electrodes. On platinum electrode, the oxidation of cysteine has been reported to occur in the potential range 0.7 to 1.45 V (vs NHE). Therefore, the object of this investigative study has been to find an active complex that could replace platinum and other expensive metals as electrodes. Such a complex should also be capable of reducing the potential at which the oxidation of cysteine occurs on carbon electrodes. As a result, this manuscript gives a full report on the investigative study of electrocatalytic activity of molybdenum phthalocyanine complexes towards detection of cysteine. Molybdenum phthalocyanine, OMo(OH)Pc, and its tetrasulfonated derivative, [OMo(OH)TSPc]⁴⁻ were successfully used to reduce the potential needed to initiate the oxidation of cysteine on carbon paste electrodes (CPE). The oxidation of cysteine on CPE modified with [OMo(OH)Pc]⁴⁻ was found to occur at 0.29 V (vs Ag/AgCl), and in the presence of [OMo(OH)TSPc]⁴⁻ species in solution the oxidation occurred at 0.33 V (vs Ag/AgCl). Molybdenum, in the oxidation states of Mo(IV), Mo(V) and Mo(VI), is found in biological systems as an essential trace element, participating in a number of enzymatic reactions, where it is believed to be coordinated to sulphur-containing ligands in many molybdenum enzymes. This therefore explains why molybdenum phthalocyanines were employed in electroanalytical detection of sulphur containing amino acid, cysteine. Electrochemical methods have also been successfully used in detection of environmental pollutants such as phenolic compounds. Phenolic compounds are oxidised at readily accessible potentials. However, like cysteine, there are problems associated with the electrochemical detection of these important environmental pollutants. Their electrooxidation is known to form dimeric and/or polymeric oxidation products which adsorb onto the electrode surface, thus -videactivating it. Therefore, to address this problem, cobalt phthalocyanine (CoPc) and its tetrasulfonated derivative, [CoTSPc]⁴⁻ were employed in electrocatalytic detection of phenolic compounds. These complexes were found to increase the anodic peak currents for the oxidation of o-cresol, m-cresol, p-cresol, phenol, 2-chlorophenol and 4-chlorophenol. In addition, CoPc deposited onto the glassy carbon electrode improved the stability of the electrode, by reducing electrode poisoning caused by the electrooxidation products of the mentioned phenolic compounds. The potential at which the oxidation occurred and the current response of individual phenolic compounds depended on the degree of substitution and the type of substituent on the phenol molecule. In general, the current response was found to be lower for chlorinated phenols compared with the cresols and phenol. To establish the role of the central metal in the catalytic process, comparison of the electrocatalytic activity of some of the first row transition metal phthalocyanines, for the detection of mono-substituted phenolic compounds, showed the following trend: Co⁽¹¹⁾ > Mn⁽¹¹⁾ > Fe⁽¹¹⁾Pc > Ni⁽¹¹⁾Pc > Cu⁽¹¹⁾Pc > H₂Pc > Zn⁽¹¹⁾Pc > Bare GCE. A report is also given on electrocatalysis using [CoTSPc]⁴⁻ electrochemically deposited on the glassy carbon electrode. This was also found to enhance the anodic peak currents for the oxidation of all phenolic compounds. A report on the effects of scan rate, operating potential, analyte concentration and other variables is also given.
  • Full Text:
  • Date Issued: 1998

How green is our future? Thor Chemicals: a case study in South African environmental policy

- Flint, Adrian

  • Authors: Flint, Adrian
  • Date: 1998
  • Subjects: Environmental ethics , Environmental policy -- South Africa , Environmental policy -- South Africa -- Case studies , Environmental degradation -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2776 , http://hdl.handle.net/10962/d1002986 , Environmental ethics , Environmental policy -- South Africa , Environmental policy -- South Africa -- Case studies , Environmental degradation -- South Africa
  • Description: This study focuses on South African Environmefltal policy; in particular its policies regarding hazardous waste. These policies are addressed within the framework of a case study which serves as basis to critically evaluate government environmental policies both past and present. The thesis examines South African environmental policy against the backdrop of competing schools of thought regarding the relationship between growth and development on the one hand and long term environmental security on the other. Development strategies such as Sustainable Development and the government's Growth, Employment and Redistribution as well as philosophies such as Deep Ecology will be discussed. The thesis argues that Non-Governmental Organisations are the holders of a real environmental ethic and thus their role in preventing environmental degradation is of critical importance. Furthermore, it is imperative that this ethic be disseminated across society if South Africa is to successfully pursue sound environmental policies. This argument is pursued by way of a case study, Thor Chemicals: a company responsible for the running of the largest mercury recovery facility in the world. This plant, which operated in Cato Ridge, KwaZulu-Natal, has been the source of much controversy since it was found that many of its employees and ex-employees were suffering from severe mercury poisoning resulting in two fatalities. The company was also involved in the importation of hazardous wastes as well as the pollution of the surrounding environment. Thor is currently the subject of inquiry by the government-appointed Davis Commission. It is pointed out that ill the past South Africa held no real environmental ethic and environmental degradation ensued as a result. The presented thesis argues that, despite assurances to the contrary, the present government is also without a true environmental ethic that will be effective in preventing future degradation.
  • Full Text:
  • Date Issued: 1998
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