3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Drawing on Words: Jasper Johns's Illustrations of Samuel Beckett's Foirades/Fizzles(1994) Richards, Colin PeterBetween 1973 and 1976 artist Jasper Johns produced some thirty-three illustrations to accompany five prose texts authored by Samuel Beckett. The result was the book Foirades!Fizzles, published in New York in 1976. Almost without exception the critical literature published on this book draws the relation between image and text away from any idea of illustration. And this only when the idea is not simply ignored. This critical attitude reflects a wider tendency in especially elevated critico-aesthetic discourse to consider illustration as aesthetically and textually debased. Bracketed off, illustration merely signals a parasitic relation. Compromising the integrity of the texts it enjoins, it articulates a secondary aesthetic of the accessory. This view seems unproductive not only when applied to Johns's work, but also to image-text combinations more generally. The sheer incidence of such combinations (including illustration) in recent and current aesthetic production suggests that the indifference or prejudicial critical reflex routinely provoked by illustration marks a moment of poverty in contemporary critical thinking. This moment appears solidly rooted in a once dominant and still apparently powerful formalist and purist impulses within modernist discourse. The persistence of these impulses suggests the survival of unexamined, limiting and tenacious critical assumptions. A closer examination of selected texts - pre-modernist, modernist, and post-modernist - point beyond these assumptions. Here the logic of the supplement in particular illuminates very specifically how illustration might come to function, and where its incendiary critical potential may lie. The supplement resists the easy hierarchisation or even synthesis of different texts which has been the fate of illustration. It renders illustration both critically robust and radical. The concept of allegory is also illuminating here. It not only helps us understand better the fate of illustration within modernism and postmodernism, but also provides for enlightening readings of Foirades!Fizzles. In turn, a revaluation of illustration opens up a more productive view of allegory in both modernist and postmodernist discourse. Illustration, in coordinating different semiotic systems, however marginally, can function as a framing, focusing and spacing device, a way of bracketing and specifying themes, structures and forms within a given textual complex, a way of opening readings otherwise foreclosed or overlooked. In this study such readings are articulated through a set of textual configurations which include: vision and perception; the body, eye, and skin; calibration, measurement, and point of view; memory, repetition and originality; and finally liminality, ambiguity and metastable signification. Against the grain of published opinion there is then much to be gained by recognising the capacious critical potential of illustration, what we might term its 'motivated contingency'. Rather than being considered critically inconsequential or an aesthetic impedin1ent, illustration may in fact provide an almost unique opportunity not only to explore issues germane to Johns's work (both independently and in relation to Beckett's texts), but also to address certain important critical debates within postmodern discourse. Its value may be felt in reading Foirades!Fizzles, in reading other image-text combinations, and the broader relations between visual art, literature, and language.Item The penetration and fracturing mechanisms generated in brittle rock by the impingement of a high velocity jet(1992) Giltner, Scott GeorgeExtensive studies on the jet penetration process in ductile metal targets have been previously carried out in numerous investigations. As a result, the penetration in ductile targets has been characterized by various theoretical models. However the penetration of brittle materials, particularly rock, has received considerably less attention. The lack of information concerning brittle materials is important as major differences between penetration in ductile and brittle materials have been observed. In most instances the actual penetration in brittle materials is far less than that given by theoretical calculations. This thesis presents an investigation into the high velocity jet penetration of brittle rock. The aim of this work is to describe the dynamic forces transmitted into the rock by the jet and the subsequent response of the rock to these forces. It is shown that existing penetration theories do not adequately describe penetration in rock. Of all the jet and target properties considered in the theories examined, target strength is shown to be the most relevant for predicting penetration depth. Recovery of the actual hole created was achieved by overcoring of the hole. Detailed measurements of the hole profile and fracture zones around the hole are presented. From the recovered samples of the hole, thin and polished sections were obtained for microscopic analysis. Results from the microscopic examination of these specimens are discussed from which temperature and pressure information are derived. In order to provide an adequate description of the penetration process, instrumentation was used to measure the penetration velocity, particle acceleration, and dynamic strain generated in the rock. From the instrumentation the interface pressure, dynamic stress, and dynamic strain generated in the rock are quantified and related to the various fracture zones identified around the hole. The results of these tests indicate that penetration in rock can be separated into three distinct phases. Initially the rock behaves as a hydrodynamic fluid should the interface pressure be very high. However as the interface pressure drops, the strength of the rock becomes evident and the second phase is entered into. The second phase is characterized by rapid changes occurring in the behaviour of the rock. Once the behaviour of the rock has stabilized, the third and final phase of penetration is entered. This final phase is predominantly controlled by the rock strength. As a result of this investigation, a better understanding of the interaction between the rock target and penetrating jet has been established. Additionally the behaviour of rock subjected to very high shock pressure has also been described. This has allowed better insight into the material properties governing the penetration process and the fracturing of rock from purely dynamic stresses.Item Reproductive labors: the politics of women's health in South Africa, 1900 to 1960(1995) Burns Catherine EileenThis dissertation opens the theme of reproduction in southern Africa to historical scrutiny. To do this, the work is divided into nine chapters, each tackling related aspects of this field of inquiry. It examines the development of a definition and practice of public health in the early decades of this century in Johannesburg and traces the local history of maternal health, mothercraft, and midwifery in the context of urban segregation. Healing practices that existed outside of official control, namely the work of family midwives and health practitioners many of whom were black women with skills and experience acquired in rural settings, are explored. Here, the commonplace separation of "Western biomedicine" and "indigenous African" practices concerning health and midwifery are challenged, using the records of an extraordinary herbalist and midwife, Louisa Mvemve. In 1928 the Bridgman Memorial Hospital was established as a site for a massive project to train and certify a cadre of black midwives and as space for scientific research concerning the bodies, birthing capacities, and gynecology of black women. The development of a local specialty termed "Bantu Gynaecology" is traced, indicating the powerful linkages between the development of anthropological and scientific knowledge about black women. The heart of this dissertation is an examination of the complex and contradictory history of the Bridgman through archival records and the oral testimony of women who trained at the Hospital and who gave birth there from 1930 to 1962. The politics of contraception and birth control in Johannesburg and the history of debates about sexuality and illegitimacy lead to a discussion of the increasingly didactic involvement of local and central state officials in the policing of black women in the city. This increasingly invasive state intervention in birth, "family planning" and controlling the reproductive labor of black women after 1950 is the subject of the last section.Item Vrouetaal in drie Afrikaanse tydskrifte: Die Boervrou (1919-1931), Die Huisgenoot (1932-1948) en Sarie (Marais) (1949-1989)(1993) Slabbert Sarah Johanna CatharineThis study is based on three main hypotheses: a) The discourse between a women's magazine and its reader can be regarded as a specialized type of woman-to-woman communication and can therefore be placed within the paradigm of women's language. b) Because language is a social semiotic, changes in the social position of women will be reflected in the lexicogrammatical features of the women's magazine. c) Changes in the social position of women will mainly be reflected in the realm of interpersonal meaning and consequently one can expect movement in those lexicogrammatical features that are associated with interpersonal meaning. The research traces the historical development of this discourse type in three Afrikaans magazines: Die Boerevrou (1919-1931), the women's section of Die Huisgenoot (1932-1948) and Sarie(Marais) (1949-1989). The focus is on three core sections of the women's magazine: the discourse between female and male characters in love stories, and the discourse between magazine-speaker and reader-listener in general articles and in advertisements. Theoretically, the research links up with the functional model of Halliday. The method is mainly quantitative and based on the Interactional Process of Analysis (IPA) of Bales (1970) as interpreted by Preisler (1986), as well as on the work of Fowler et al. (1979). Three sets of specific hypotheses have been defined. The first is based on the stereotypes of women's language, the second on IPA categories and the markers of tentativity, and the third on the markers of control as described by Fowler et al. (1979). When relevant, the behavior of additional variables that have shown themselves to be sensitive to time, or which have been previously researched in other material, e.g. Stoops (1972), was also described quantitatively. For the advertisements changes in the context of the situation were also described in qualitative terms. The results have proved the central assumption of the study to be correct, namely that the discourse of women's magazines would be sensitive to the defined variables. The most important findings were the following: In all the examined volumes, with the exception of 1970/71, a significant difference between the linguistic behavior of male and female characters in the magazine stories was found. This difference is however not always equal and does not always concern the same variables. In both the magazine articles and the advertisements there is a movement away from an explicit task-oriented role towards a more socio-emotional role. In the articles, it entails a massive shift from task-oriented functions towards the function ''Dramatizing" (Bales 1970), whereas the shift in the advertisements is not as large and towards "Friendly" (Bales 1970}. The study has shown that a quantitative instrument that has been developed for the description of group interaction on a synchronic level can also be successfully applied to a historical study on written language. It is hoped that it has also demonstrated the value of functionally defined variables and contrastive material for stylistic analysis.Item Cost and quality of care: a comparative study of public and privately contracted chronic psychiatric institutions(1998) Porteus, Kimberley AnnItem The role of the polymerase chain reaction in the routine haematology laboratory.(1993) Gunther, Karen ElizabethThe Polymerase Chain Reaction (PCR) provides a means of amplifying target sequences of DNA exponentially and it is rapidly becoming an indispensable tool in the research laboratory. Many other molecular genetic techniques used for research are far too laborious and expensive to be used for routine diagnostic purposes but PCR has the potential to be different. This Research Report assesses the possible role of PCR as a routine diagnostic tool in the haematology laboratory. In the context of haematology, PCR can be used to detect both "pathological" and "physiological" target sequences present within the genome. Pathological sequences of interest would include mutations, deletions, insertions or translocations not present within the normal genome but which may arise either as a result of an hereditary abnormality or be acquired somatically. Sensitive detection of such sequences is useful for diagnostic purposes and can also be relevant in determining prognosis, evaluating response to therapy and following up minimal residual disease in the context of haematological malignancies. PCR detectable physiological sequences would include the immunoglobulin and T cell receptor gene rearrangements normally present within the genome of cells of the appropriate lineage. These rearrangements differ for each lymphocyte within a polyclonal population but are identical among members of a clone arising by proliferation of a single precursor cell. They can therefore be of value not only in determining cell lineage but also as markers of clonality. In this study the practical aspects of using PCR were assessed by setting up the technique of amplification of immunoglobulin gene rearrangements. The cost of reagents and disposable equipment, as well as that of major items of equipment required which are not usually available in a routine laboratory was also determined. In addition, peripheral blood and bone marrow samples reaching the Haematology Laboratory of the Johannesburg Hospital were analysed to assess the potential demand for such investigations. Once appropriate reaction conditions for the primers used had been established, PCR was found to be quick, technically simple and relatively inexpensive. Sufficient numbers of appropriate samples for which PCR analysis could potentially be of value were received in the Johannesburg Hospital Haematology Laboratory in the periods assessed, to indicate that diagnostic PCR, if available, would be well utilised. Some problems were encountered, particularly with regard to variability in the extent of amplification obtained. Thus for routine diagnostic purposes, extensive research and development of each set of primers to be employed will be necessary to make the technique more reliable and consistent. Adequate quality control will also be essential if PCR is to be used for diagnostic purposes. However, once these issues have been addressed, PCR should definitely find a place as a routine diagnostic tool in the haematology laboratoryItem The impact of mining on the South African economy : an empirical review(1999) Stilwell, Lancelot CharlesMany people and organizations, including the government, claim that mining is the cornerstone of the South African economy. However, no documentation of either the inter-sector or the intra-sector relationship of the mining industry with the rest of the economy exists to support this claim. The purpose of the research undertaken in this thesis is to evaluate and quantify these relationships, during the period 1971 to 1993, using input-output multipliers. The conclusions reached are that: (i) Increased output from mining activities did not have the greatest mean impact on GDP. (ii) Income generated in mining activities had a significantly less mean impact on GDP than did income generated in the majority of other sectors. (iii) Increased output from the mining activities did not have the greatest mean the impact on employment. (iv) Increased employment in the mining industries had a significantly less mean the impact on employment than did employment in the majority of other sectors. (v) The sector that consistently benefited the most from increased mining output was "wholesale and retail trade and motor trade". None of the heavy manufacturing industries benefited significantly from increased mining output. (vi) The impact, of increased mining output and increased employment in the mining activities, on suppliers of intermediate input, was less than the mean impact of the whole economy. The mining industry does generate large flows of income, but this income does not benefit the economy to the same extent as several other sectors. The thesis supports a previous study that found that the forward linkages between mining and the rest of the economy are indirect and through the world economy. Finished products are imported to facilitate the export of raw mineral resources, which is the driving activity of the economy. It is not possible to determine the individual importance of minerals other than coal and gold. "Other minerals" should be segregated in future Tables. Neither GDP nor input-output tables take any account of the depletion of natural reserves. This is an important limitation on their use as an indicator of income in a minerals abundant economy and is an area for further research.Item Iron and Malaria(1997-02-07) Van Zyl, Robyn L.Malaria is one of the most devastating infections found in man and the resurgence of drug resistance has prompted the search for novel chemotherapeutic strategies. Clinical observations have exposed the susceptibility of malaria parasites to iron deficiency, thus the metabolism of iron in parasitized erythrocytes could be a potential antimalarial target. In in vitro experiments, the parasites accumulated approximately four times more non-transferrin-bound iron than diferric transferrin. Both forms were accumulated in a concentration- and time-dependent manner, with more iron being associated with the trophozoite stage than the ring stage. The ferric iron chelating agent, desferrioxamine inhibited the uptake of transferrin and non-transferrin-bound iron in a concentration dependent manner. 2,2’-Bipyridyl, a ferrous iron chelating agent also inhibited the uptake of non-transferrin-bound iron, but did not affect the uptake of diferric transferrin. This indicated that the parasite does not accumulate diferric transferrin by transferrin-receptor mediated endocytosis, but rather by a non-specific endocytotic pathway. A large quantity of the accumulated iron was associated with the parasite haemozoin. Desferrioxamine effectively reduced the amount of iron associated with the haemozoin, whilst 2,2’-bipyridyl did not, which indicates that the haemozoin-associated iron is in the ferric state. The parasitized erythrocytes were more susceptible to haemolysis by the haemozoin subunits than the uninfected erythrocytes. The presence of chloroquine and 2,2’-bipyridyl potentiated the haemolysis induced by the subunits, whilst desferrioxamine protected the parasitized erythrocytes. The plasma chelating agents and aminocarboxylate compounds were not as effective in inhibiting parasite growth, as desferrithiocin, bathophenanthroline, desferrioxamine and 2,2’-bipyridyl which avidly chelate iron. The additive interaction between the latter two agents and chloroquine, quinine and pyrimethamine, completely eliminated the malaria infection. As did the combination of two lipophilic ferrous or two hydrophilic ferric iron chelating agents, as well as the combination of a hydrophilic ferric and lipophilic ferrous iron chelating agent. Whilst the combination of hydrophilic ferric and hydrophilic ferrous iron chelating agents antagonised each others antimalarial actions. Variables such as inoculum size, extracellular pH, cation supplementation and stage dependency, all affected the antimalarial activity of the iron chelating agents. Thus, the unique pathways involved in the iron metabolism of P. falciparum-infected erythrocytes, could be potential targets for new antimalarial drugs, which are membrane permeable and avidly chelate iron.Item The homelessness problem: planning, phenomenology, and gender perspectives(1997) Olufemi, Olusola AdebolaThe thesis considers the problem of homelessness from planning and gender perspective, with the purpose of applying or using a theoretical approach, which will lead to an understanding of, and practical solutions to the problem in South African cities and which will have international applicability. The study notes that women constitute a population at risk. \Vomen are becoming more vulnerable to street homelessness because of the increasing rate of urbanization, population growth, poverty, unemployment and changing family structure (female-headed households, single mothers, divorcees and widows). The study states that past approaches in solving the homelessness problem have been fragmentary, uncoordinated and there has been no definitive institutional intervention. It points out the absence of a clear government policy, lack of clear planning responses/models/approaches and the lack of involvement of the street homeless women themselves in addressing the homelessness problem. The study investigates the various principles pertaining to the homelessness problem internationally. It gives definitional as well as gender approaches to home and homelessness. It shows that women constitute part of the new and hidden homeless population. The study considers past planning approaches/traditions which might have had relevance in understanding and resolving the homelessness problem. It also considers philosophical approaches which might also have relevance in which context phenomenology is identified as a philosophy that offers an appropriate methodological base. This has been adapted for the purpose of planning. It is an interpretive approach and it is more people-centred than the past planning approaches. A survey was conducted in the Johannesburg inner city which is rapidly becoming the locale of the street homeless people. The survey procedure adopted in this study is in three parts: 1. Reconnaissance survey; 2. Qualitative survey; 3. Quali-quantitative survey. The reconnaissance survey identifies shelter types and abodes of the street homeless. It enumerates the number of street homeless people. This is to determine the numerical and spatial extent of the phenomenon. The survey indicates that the street homeless abodes are disorganised and overcrowded. The abode types are usually in the form of open halls, open spaces, shacks (Mekhukhu) built with cardboard boxes and pavements or road kerbs turned into dwelling places. The abodes lack water, electricity and toilets. Contrary to the above, the shelters provided by institutions for the street homeless are more organised and have the essential or basic facilities. With regard to the qualitative survey, a focus group discussion and participant observation method were used in obtaining information from women. This survey conforms to the phenomenological methodology adopted in the study. The original and lifeworld experiences of the street homeless women were obtained and interpreted. They do not have a fixed schedule, they live each day as it comes. They spend the day talking, gossiping, singing, washing, sometimes doing cultural activities, begging, cooking and soliciting for male clients. The quali-quantitative survey, through questionnaires, elicited information on the socio-economic and socio-cultural characteristics of the street homeless people. That includes their age, education, marital status, occupation, ethnicity, nationality among others. 78 per cent are black (Africans), 14 per cent are coloured, 2 per cent are Indian and 6 per cent are white. Out of these, 36 per cent are women. About 17 per cent of these women have no education and 67 per cent are single. Among the single women, 60 per cent are single mothers (with·their children living with them) and 40 per cent have no children. The survey reveals that the first three priorities of the street homeless women are employment, education and housing. It also indicates the main causes of street homelessness as unemployment and poverty, the consequences of which were manifest in crime, muggings, rape, harassment, diseases such as tuberculosis, dysentery and diarrhoea, dermal infections, pneumonia and sexually transmitted diseases. The study estimates that about 20 per cent (one fifth) of the street homeless population between 19 - 29 years in Johannesburg could be HIV/ Aids positive.Item Synthesis, development and characterisation of dehydrated castor oil poly (glyceryl phthalate) alkyd resins(1994) Nzeru, Arnold.The dissertation studies the synthesis, formulation development, crosslinking and spectral characterisation of dehydrated castor oil poly(glyceryl phthalate) alkyd resins for use as air-dry surface coating vehicles. Synthesis of alkyd resins involves simultaneous dehydration, alcoholysis and polyesterification reactions. Dehydration of castor oil is achieved in situ under phthalic anhydride catalysis. Alcoholysis of dehydrated castor oil by glycerol is also achieved in situ to form predominantly the monoglyceride. Polyesterification of the resultant mono- and diglycerides is realised through interaction with phthalic anhydride. The reaction is carried out at 280°C for 3 hours and at 225°C for 2 hours under azeotropic distillation with xylene. The parent poly(glyceryl phthalate) alkyd resin is synthesized by reaction of castor oil, glycerol and phthalic anhydride to a predetermined acid value. Formulation development experiments were carried out to study the effect of variations in the dibasic acid to polyol/oil and polyol to oil ratios on alkyd resin properties. Model formulations exhibiting the best alkyd performance were developed. Predictive model formulation equations were derived from model formulation data and their limits of reliability and applicability established. The formulation of water soluble alkyd resins is modified to introduce pendant carboxylic acid groups along the polymer skeleton. Water solubility is achieved by neutralisation of the residual pendant carboxylic acid groups by 'fugitive' amines to yield water soluble alkyd soaps. The effect of variations in the nature and level of incorporation of amine is investigated. Alkyd resin solubilisation and resin acidity guide formulae were studied and developed. Cross-linking chemistry of alkyd resins, both in the reactor (gelation) and on application (film formation) is investigated. Gelation manifested itself in two different forms, thermoplastic and thermosetting. An important alkyd constant, K, was established as an indispensable tool in control of premature gelation and in the prediction of resin drying characteristics. Autooxidation and solvent evaporation are the two competing curing mechanisms encountered in film formation. The nature and influence of each curing mechanism on the rate of cure and film characteristics is highlighted. Catalysis experiments were conducted with metallic driers (Co2 Mn2 and Pb2} to bring the rate of drying of resin films to economically feasible limits and catalyst addition levels were established. New spectral characterisation techniques based on Fourier Transform Infrared spectroscopy were investigated. An extensive study was carried out on FT IR spectral data to establish qualitative and quantitative relationships between transmission peak ratios and alkyd resin composition. Series dependent and series independent correlation equations, useful in quantifying alkyd resin components were derived. A new FT IR spectroanalytic characterisation method for dibasic acids is proposed. The method, if adopted, affords both qualitative and quantitative characterisation of the dibasic acid component in the alkyd resin matrix and it is envisaged the technique will supersede conventional methods in terms of speed and simplicity.'