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Aspects of the ecology and biology of Gilchristella aestuarius (G & T) (Pisces: Clupeidae) in the Swartkops estuary, Port Elizabeth

  • Authors: Talbot, Marie Marcel Jean-Francois
  • Date: 1982-12
  • Subjects: Fishes -- Ecology -- South Africa -- Swartkops River Estuary , Swartkops River Estuary (South Africa)
  • Language: English
  • Type: Master's theses , Manuscripct
  • Identifier: http://hdl.handle.net/10948/52352 , vital:43613
  • Description: The Department of Zoology at the University of Port Elizabeth has an ongoing programme on the Swartkops estuary with the eventual aim of drawing up the energy pathways of the system. Marais (1976) has investigated the nutritional ecology of the grunter Pommadasys cormersoni while Melville-Smith (1978) and Melville-Smith and Baird (1981) reported on the ecology of larval fish. Winter (1979) studied the ecological parameters of fish populations, but this work was not a detailed account of each population. Wooldridge (1979) studied components of the 3 zooplankton community in some detail. It became evident that there was a significant lack of understanding of the ecological relationships between plankton and piscivorous fish, which was crucial to the elucidation of the interactions and trophodynamics of the Swartkops estuarine system. Since G. aestuarius is an important link in the energy pathway from the plankton to the nekton, and in terms of numbers dominates the seine net catches made in the estuary (Winter, 1979), this study was motivated. The aim was to investigate the important biological parameters of the estuarine round herring population namely the population structure, distribution and abundance, individual growth rate from field data, the food and feeding habits, reproduction and respiration, all of which are essential for the understanding of the dynamics of a species. These parameters were later converted into energy terms and the construction of an energy budget was attempted. , Thesis (MSc) -- Faculty of Science, 1982
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  • Date Issued: 1982-12

A logos of difference: the Kantian roots of Derrida's deconstructive thinking

  • Authors: Hurst, Andrea Margaret
  • Date: 1999
  • Subjects: Derrida, Jacques -- Philosophy , Deconstruction , Philosophy
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:11003 , http://hdl.handle.net/10948/d1015554
  • Description: This study concerns a contemporary articulation of the age-old limit/possibility (truth/scepticism) contest in Western metaphysics. Traditional `either/or' logic advises that scepticism is a necessary consequence of the assailability of truth; hence the concerted effort in the history of philosophy to preserve the possibility of truth against any flicker of uncertainty. Here, it is argued that contemporary thinking sees the possibility of `absolute' truth lose its ground. However, a concomitant shift to a `logos of difference' averts the consequence of scepticism. Thus, the justification for this study could be articulated in terms of the imperative, if a cardinal moment in contemporary thought is to be sustained, to understand this shift in logos, work through its implications and learn to live with its effects. In this respect, an attempt is made throughout to situate and interpret Derrida's `deconstructive thinking' as exemplar. Derrida's thinking finds roots (not without signs of insurrection) in Kant's `Copernican revolution,' construed as the first shift towards the contemporary logos in question. Here, Kant refuted the postulate of an independent `world' by demonstrating that `reality' was the result of a cognitive order imposed on what `exists' by the rational subject. Knowledge, therefore, depended not on matching statements with pre-existing `things,' but on knowing the `rules' that determined how an object had to be if it was to be known at all. Kant maintained that certain, objective knowledge was possible, due to the completeness and universality of the forms of intuition and the categories of the understanding. Kant's `Copernican revolution' provided the opening for a second shift inaugurated by the so- called `linguistic turn.' Here, thinkers contested what Kant took for granted; namely that `constitutive interpretations' (cognitions/concepts) formed a `reality' independently of language. The basic premise underpinning the `linguistic turn,' therefore, is that language (signification) and `reality' are inseparable. Henceforth, the possibility of final, enduring `constitutive interpretations' whose `truth,' in principle, is discoverable, depends on whether or not the language which mediates human rationality can form a complete and universal system. This question resurrects the very limit/possibility debate (in the form of a structuralism/postmodernism stand-off) that Kant thought he had resolved in mediating between rationalist and empiricist extremes. In contemporary terms, philosophers who, bound by either/or logic, wish to avoid the sceptical trap of `anything goes' postmodernism, must assume that language (signification) can form a complete and universal system. However, in his deconstructive readings of Husserl, Saussure and `structuralism,' Derrida demonstrates the untenability of this assumption. At the same time, he shows that the sceptical `alternative' may be avoided by recognising the limitations of `either/or' logic. Again, Derrida's thinking may be traced to Kant's; this time to his analysis of the `first antinomy.' In accordance with Kant's analysis here of what is ultimately the logic of `complex systems' (Cilliers), Derrida offers a `logos of difference,' which skirts the strictures of structuralism while avoiding the trap of postmodern scepticism by accommodating both moments of limit and possibility in an indissoluble interplay.
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  • Date Issued: 1999

Physiological and non-physiological induction of gastrointestinal differentiation

  • Authors: Brauns, Seth Clint Aron
  • Date: 1999
  • Subjects: Gastrointestinal system -- Differentiation , Gastrointestinal system -- Physiology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11089 , http://hdl.handle.net/10948/d1015521
  • Description: The human colonic carcinoma cell lines HT-29 and Caco-2 both exhibit structural and functional differentiation under appropriate culture conditions. HT-29 can be induced to differentiate by treatment with short-chain fatty acids or acetoacetate. Caco-2 cells differentiate spontaneously upon contact inhibition. In this study HT-29 cells were treated with 5 mM acetate, propionate, butyrate and acetoacetate (physiological inducers) to assess their effects on the expression of carbonic anhydrase 1, sucrase-isomaltase and alkaline phosphatase which are reported to be markers of gastrointestinal differentiation. The maturation induction observed was compared to that of the spontaneous differentiation observed in Caco-2 cells. Assays were performed over an 18 day period. Results showed a close correlation (p < 0.05) between HT-29 and Caco-2 cell on days 4 and 12. These results indicate that differentiation reported in both cell lines is comparable and can be used as a basis for further comparative studies. In addition, parallel experiments to the above were conducted using a selection of nine rationally designed cyclic dipeptides (CDPs) potential drug entities which were chosen as non-physiological inducers. The results showed that the cyclic dipeptides were able to induce the gastrointestinal phenotype as observed in HT-29 cells treated with physiological inducers. Studies on the effects of energy-related metabolism in HT-29 and Caco-2 cells as induced by physiological and non-physiological inducers indicated that energy metabolism is a significant role player in gastrointestinal differentiation. The results reported show a decrease in ATP concentrations indicating that the cyclic dipeptides, like physiological inducers, affect the energy state of the HT-29 cells and thus may effect the differentiation of these cells. A positive correlation was found between histone phsophorylation and differentiation confirming that histone phsophorylation was partly responsible for the decrease in ATP concentrations. It is suggested that the induction of differentiation in HT- 29 cells could be either due to non-specific transcription of genes by activation of a chromatin switch or specific by the activation of signal transduction pathways based on the flux of ATP through the cells. Differential display RT-PCR is probably the most sensitive method that could be used to validate the suggestion of either a nonspecific transcription of genes or a specific differentiation reported for HT-29 cells.
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  • Date Issued: 1999

Main thesis title: Onderwysers se belewing van multikulturele onderwys

  • Authors: Strydom, Louise
  • Date: 1999-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: Afrikaans
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/60003 , vital:62732
  • Description: The South African Schools’ Act of 1996 terminated segregated education in South Africa. Multi-cultural education has become a reality in the new democratic South Africa. As a result of this major shift in policy, the researcher probed for an answer to the following question: “How does the teacher, especially the teacher already in service, experience this new situation regarding multi-cultural education?” To find an answer to this question, a literature study and empirical research, making use of a representative sample of respondents in the Southern Cape, were undertaken. The researcher has personally experienced the challenges of having to adapt from a mono-cultural teaching environment to a multi-cultural teaching environment at school level, hence a further interest in this research problem. Relevant terminology was highlighted and a brief historical synopsis of the course that multi-cultural education took in Western societies such as the USA, Canada, Australia and Britain was studied. These sources were utilised to draw a comparison with the South African situation. A concise synopsis of the history of multi-cultural education in South Africa was also undertaken to highlight the complexity of the educational situation presently being experienced in South Africa. The empirical research, with a target group representing teachers in the Southern Cape, was undertaken by means of a self-compiled questionnaire to make an analysis of teachers’ attitudes, expectations and perceptions of multi-cultural education as experienced in the classroom. The information obtained from the respondents indicated a generally positive attitude towards multi-cultural education amongst teachers. A great need for in-service training also became evident. xvi The researcher has thus made recommendations regarding in-service training that she thinks is of utmost importance. The practical problems that were highlighted during the research, make a vital contribution towards the successful implementation of multi-cultural education in South Africa. , Thesis (DEd) -- Faculty of Education, 1999
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  • Date Issued: 1999-04

On using AMOS, EQS, LISREL, Mx, RAMONA and SEPATH for structural equation modeling

  • Authors: Peprah, Syvester
  • Date: 2000
  • Subjects: Latent variables , Multivariate analysis , Mathematical statistics -- computer programs
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11082 , http://hdl.handle.net/10948/279 , Latent variables , Multivariate analysis , Mathematical statistics -- computer programs
  • Description: Structural Equation Modeling is a common name for the statistical analysis of Structural Equation Models. Structural Equation Models are models that specify relationships between a set of variables and can be specified by means of path diagrams. A number of Structural Equation Modeling programs have been developed. These include, amongst others, AMOS, EQS, LISREL, Mx, RAMONA and SEPATH. A number of studies have been published on the use of some of the applications mentioned above. They include, amongst others, Brown (1986), Waller (1993) and Kano (1997). Structural Equation Models are increasingly being used in the social, economic and behavioral sciences. More and more people are therefore making use of one or more of the Structural Equation Modeling applications on the market. This study is performed with the aim of using each of the Structural Equation Modeling applications AMOS, EQS, LISREL, Mx, RAMONA and SEPATH for the first time and document the experience, joy and the difficulties encountered while using them. This treatise is different from the comparisons already published in that it is based on the use of AMOS, EQS, LISREL, Mx, RAMONA and SEPATH to fit a Structural Equation Model for peer influences on ambition, which is specified for data obtained by Duncan, Haller and Portes (1971), by myself as a first time user of each of the programs mentioned. The impressive features as well as the difficulties encountered are listed for each application. Recommendations for possible improvements to the various applications are also proposed. Finally, recommendations for future studies on the use of Structural Equation Modeling programs are made.
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  • Date Issued: 2000

Ostrich calpastatin purification and partial characterization of the liver inhibitor

  • Authors: Roman, Henry James
  • Date: 2000
  • Subjects: Calpastatin , Protease inhibitors , Ion exchange chromatography , Ostriches
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11090 , http://hdl.handle.net/10948/d1015522
  • Description: The isolation and purification of calpastatin from ostrich liver is presented, along with its physicochemical and kinetic properties. By using extraction from liver, ion-exchange chromatography on DEAE-Toyopearl, heating to 90 °C for 10 min and rechromatography on Toyopearl Super-Q 650 S, ostrich calpastatin was isolated and purified from ostrich liver. The purified intact calpastatin showed homogeneity on SDS-PAGE (Mr of 105.6 K). Amino acid analysis showed that ostrich calpastatin resembled that of rabbit liver and human erythrocyte calpastatin. An N-terminal sequence could not be obtained because the N-terminus was found to be blocked by an as yet unknown amino acid residue. The Mr values of degradative forms of ostrich liver calpastatin were determined to be 56 K and 90 K. By using PAG-IEF the pI of the intact form was determined to be 5.1. Ostrich liver calpastatin behaved characteristically like other calpastatins during kinetic analysis. Calpastatin inhibited calpain from pH 6 to 9 and was found to be unaffected by temperatures as high as 100 °C. Calpastatin also inhibited calpain activity at Ca2+ concentrations ranging from 1 to 10 mM. The inhibitor was shown to be phosphorylated because after incubation with alkaline phosphatase there was a decrease in inhibitory activity. No inhibitory effects were detected against other proteases such as chymotrypsin and trypsin, with both proteases inactivating calpastatin completely. Ostrich liver calpain was shown to have a pH optimum of 7.5 and a temperature optimum of 30 °C. In terms of its thermodynamic properties it resembled that of other ostrich proteases; DH, DS and DG being 47.07 kJ/mol, -91.1 J/mol/K and 74.237 kJ/mol, respectively. Ostrich liver calpain showed a Km of 0.14 % (w/v). The enzyme was active at both milli- and micro-molar concentrations of Ca2+. Ostrich liver calpastatin showed many physical, chemical and kinetic properties similar to those of other known calpastatins.
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  • Date Issued: 2000

Outsourcing for competitive advantage : an evaluation of an owner driver proposition in a South African removals company

  • Authors: Coleman, Belinda
  • Date: 2000
  • Subjects: Contracting out -- South Africa , Storage and removal trade -- Subcontracting -- South Africa , Trucking -- South Africa , Benchmarking (Management) -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:11002 , http://hdl.handle.net/10948/d1015540
  • Description: The aim of the research was to assess what competitive advantage a Removals company could expect to gain by outsourcing its driver function to owner drivers. An extensive literature review identified key outsourcing issues. The literature was related to a case study of Stuttaford Van Lines (SVL), a company that is experiencing problems with its current independent contractor driver arrangements and that needs to review its outsourcing decision. In order to learn from best practice in the field of outsourcing to owner drivers, a benchmarking exercise was undertaken at South African Breweries (SAB). The benchmarking exercise identified six key issues that contributed to the success of the SAB owner driver scheme. These points, together with others identified from the literature, were integrated into a recommended outsourcing implementation process for SVL. The research found that it is possible for SVL to outsource the driver function to owner drivers and that such a scheme can be expected to improve customer service levels. The success of the scheme will depend on the selection of the drivers and how effectively it is managed. It was found that it would not be profitable for SVL to outsource to owner drivers using the compensation model proposed. Cost reduction is however only one of the factors to consider in an outsourcing decision.
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  • Date Issued: 2000

Possible crosstalk between signal transduction pathways in the induction of differentiation in HT-29 cells

  • Authors: Jamie, Hajierah
  • Date: 2000
  • Subjects: Cellular signal transduction , Cell differentiation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11096 , http://hdl.handle.net/10948/d1019684
  • Description: The investigation into the mechanisms by which compounds such as butyrate induce differentiation in HT-29 cells, is lacking. The colonic carcinoma cell line, HT-29, undergoes differentiation induction in the presence of butyrate and acetoacetate. The Caco-2 cell line spontaneously differentiates on contact inhibition. In this study, a signal transduction pathway involving ATP, cAMP, Ca2+ and the transcriptional factor CREB was investigated following suggestions that the energy state of the cell and diffferentiation are linked. The activity of the MAP kinase cascade, including possible crosstalk that may exist between these pathways was determined. The HT-29 cells were exposed to 5 mM acetoacetate, butyrate, DMSO and propionate. The results of this differentiation induction were compared to Caco-2 and HeLa cells, which are cervical carcinoma cells. It was found that ATP levels are decreased on differentiation induction in HT-29 cells, which, in turn affected the cAMP concentrations. Theoretically, the inducers do not have any effect on PDE 4 activity, and may facilitate the interaction between cAMP and PKA. Influx of Ca2+ into the cells was inhibited to a degree by the inducers, which was possibly overcome by crosstalk between the cAMP and Ca2+ pathways. CREB activation, lineage-specific gene expression, ERK activity and c-myc expression were all dependent on both the inducers used and the cell-type. PKA played a major role in CREB activation in acetoacetate- and butyrate -induced HT-29, Caco-2 and HeLa cells, while a2+/Calmodulin-dependent kinases I/IV may have a secondary role. Alkaline phosphatase expression in HeLa cells was independent of CREB. Evidence that crosstalk between the MAP kinase cascade and the REBactivation pathways exist, was illustrated by increased CREB activation on ERK inhibition in acetoacetate- and butyrate-induced HT-29 and HeLa cells. Also, the role that ERK played in the cells differed with inducer and cell-type. The dependence of cmyc expression on c-jun and c-fos, appeared to be differentiation induction- and celltype specific. Results from this study indicate the potential use of acetoacetate and butyrate as anti-cancer compounds.
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  • Date Issued: 2000

The isolation and partial characterization of a2-antiplasmin and plasminogen from ostrich plasma

  • Authors: Thomas, Adele René
  • Date: 2000
  • Subjects: Serpins , Ostriches , Antifibrinolytic agents , Plasminogen , Plasmin
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11080 , http://hdl.handle.net/10948/274 , http://hdl.handle.net/10948/d1005751 , Serpins , Ostriches , Antifibrinolytic agents , Plasminogen , Plasmin
  • Description: This study reports the isolation, purification and partial characterisation of the ostrich serpin, a2AP, as well as its target enzyme, ostrich plasmin, in its active and inactive proenzyme, viz. plasminogen, forms. Three different procedures were undertaken to isolate and purify ostrich a2AP. The first one involved L-lysine-Sepharose chromatography, ammonium sulfate fractionation, ion-exchange chromatography on Toyopearl Super-Q 650S, and ostrich plasminogen-Sepharose affinity chromatography. The second procedure replaced the latter chromatographic step with gel filtration on Sephadex G-200 and hydroxylapatite chromatography, while the third one employed instead the theoretically more efficient LBSI-Sepharose chromatographic step. The third procedure yielded purified ostrich a2AP, but the degree of purity and yield were relatively low. Ostrich plasminogen was highly purified after L-lysine-Sepharose chromatography and ostrich plasmin was obtained by the urokinase-activation of the purified ostrich plasminogen Ostrich a2AP revealed an Mr of 77-84 K and two isoelectric forms of pI 3.85 and 6.18. Nterminal sequence analysis showed ostrich a2AP to have only 2 out of 11 residues in common with both those of human and bovine a2AP. Ostrich a2AP showed the largest inhibitory effects on ostrich plasmin, followed by comm. bovine chymotrypsin, trypsin and plasmin, in that order, and it appeared to be a much less potent plasmin inhibitor than bovine aprotinin, but a much more potent one than the synthetic inhibitors, DFP and EACA. Ostrich plasminogen showed an Mr of 92 K and multiple isoelectric forms (~7) in the pI range 6.01-9.18, with a major one of pI 6.01. It showed a total of 775 amino acid residues and its N-terminal sequence showed ~53 percent identity with those of human, rabbit, cat, and ox plasminogens. Ostrich plasmin revealed an Mr of 78 K, two isoelectric forms of pI 4.07 and 6.01, and a total of 638 amino acid residues. N-terminal sequence analysis showed that 2-4 residues are identical to the 5 of human, cat, dog, rabbit, and ox plasmins. The pH and temperature optima of ostrich plasmin were determined as 8.0 and 40 oC, respectively. The thermodynamic and kinetic parameters of ostrich plasmin were computed, and plasmin was shown to prefer Lys to Arg residues in the S1 position. In conclusion, ostrich a2AP, plasminogen and plasmin showed definite similarities to their mammalian counterparts, but there were also significant differences.
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  • Date Issued: 2000

Studies on the kallikrein-kininogen system of the ostrich (Struthio camelus)

  • Authors: Bothma, Leonard Frederick
  • Date: 2001
  • Subjects: Kallikrein , Kinins , Ostriches
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11067 , http://hdl.handle.net/10948/275 , Kallikrein , Kinins , Ostriches
  • Description: Ostrich organs/tissue/fluids were screened for plasma kallikrein-like, tissue kallikrein-like and tonin-like activity in a continuous-fluorogenic-assay system using Pro-Phe-Arg-7-amino-4-methylcoumarine, Phe- Arg-7-amino-4-methylcoumarine and Val-Leu-Arg--7-amino-4-trifluoro-methylcoumarine as substrates. Ostrich liver and kidney showed the highest specific plasma kallikrein-like activity. Ostrich adrenal glands and kidney showed the highest specific tissue kallikrein-like and tonin-like activity. Ostrich high molecular weight kininogen was purified from plasma and low molecular weight kininogen was partially purified. The N-terminal amino acid sequences of both high- and low molecular weight kininogens from ostrich plasma were determined. Ostrich plasma high molecular weight kininogen was purified as a 118 kD protein. The purified high molecular weight kininogen inhibits the cysteine proteinase papain at a ratio of one molecule HKG to two molecules of papain. Ornitho kinin-like molecules were detected in ostrich urine using reverse phase HPLC.
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  • Date Issued: 2001

The constitutional right of access to social security

  • Authors: Govindjee, Avinash
  • Date: 2001
  • Subjects: Social security -- Law and legislation -- South Africa , South Africa -- Social policy
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:11061 , http://hdl.handle.net/10948/280 , Social security -- Law and legislation -- South Africa , South Africa -- Social policy
  • Description: The inclusion of the right of access to social security in the Constitution did not meet with wholehearted approval in South Africa. This right, however, is of vital importance for the future upliftment of the country. The present social security system is based upon a clear distinction between social assistance and social insurance. There is a gap in current social security provisions in that the unemployed middle aged individual is not covered. Unemployment itself is one of the greatest challenges obscuring the implementation of a comprehensive social security system. The Constitutional right is to have ‘access’ to social security and the amount of resources at the state’s disposal is directly related to increasing this right, although it is true that a number of available resources are misspent. The state must take reasonable legislative and other measures, within its available resources, to achieve the progressive realisation of the right of access to social security. The principles of solidarity and ubuntu must be cultivated so that national social development becomes a concern for all citizens. There are numerous problems facing South Africans in attaining the goal of access to social security – even if national social development does become a priority. Budgetary constraints, poverty, unemployment, HIV/Aids and foreigners are examples of these. By making social security a priority for everyone, existing ideas (almost all of which have merit) may be converted into long-term solutions for poverty and unemployment. Currently, numerous opportunities to salvage the situation are being overlooked as a result of the lack of a comprehensive and structured plan to better the access to social security. The constitutional right of access to social security is enforceable, although the jurisprudence in this field remains underdeveloped. Conditions are currently favourable, within the country and beyond its borders, for an imaginative and concerted attempt to be made to find potential solutions. It is possible for resources to be increased and for tax benefits to be incorporated for businesses which have the capacity to contribute. The issue of defence spending is controversial, but could hold the key to lowering unemployment. Should jobs be created, it is likely that they will initially be of a temporary nature. Consequently, provisions are needed to ensure some guarantee of income in the lacuna between when a job is lost and another found. Ultimately, one thing is certain: the constitutional right of access to social security will only be complete once the people who are recipients of this right make sacrifices and create corresponding duties for themselves to ensure that the next generation of inhabitants of this country are not facing similar problems. The state’s goal should be to ensure that the basic rights which all people enjoy in terms of the Constitution (in particular the other socio-economic rights) are guaranteed for the duration of their existence, even if the level of benefits received by such people is low.
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  • Date Issued: 2001

The distinction between a contract of employment and a contract with an independent contractor

  • Authors: Slater, Henry John
  • Date: 2001
  • Subjects: Labor contract -- South Africa , Independent contractors -- South Africa , Contracts -- South Africa -- Cases , Liability (Law) -- South Africa , Labor laws and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:11060 , http://hdl.handle.net/10948/276 , Labor contract -- South Africa , Independent contractors -- South Africa , Contracts -- South Africa -- Cases , Liability (Law) -- South Africa , Labor laws and legislation -- South Africa
  • Description: The purpose of this treatise was to determine the distinction between the contract of service (employment) and the contract of work (independent contractor). A comprehensive literary survey was undertaken so as to establish if such a distinction does indeed exist. A logical point of departure was to study the contract of service and determine how the employment relationship is established by it. It is also necessary to establish under what circumstances a contract may be terminated and what the rights and obligations of the parties to the contract were. The contract between the parties will determine remedies to the breach of contract or applicability of labour legislation. It is also necessary to establish the definition of an employee under various statutes so as to understand what remedies exist should rights be infringed upon. Statutes considered include the Constitution of the Republic of South Africa, Labour Relations Act, Basic Conditions of Employment Act, Employment Equity Act, Unemployment Insurance Act, Compensation for Occupational Injuries and Diseases Act, Skills Development Act and the Income Tax Act. The effect of insolvency of the employer on the employee is also discussed. Outsourcing has played a major role in the emergence of the independent contractor. This phenomenon is considered from the point of the employer in terms of the reasons for choosing the option of outsourcing and the associated risks. The employee perspective is also dealt with in terms of why an employee would change his/her employment status. The various tests historically applied to determine the status of a worker is also discussed. These include the control, organisation, dominant impression and economic tests. Currently the dominant impression test is the one that is being applied to determine the employment relationship. Extensive reference was made to case law. United States of America cases are referred to with specific reference to the 20 Factor Test applied by the Internal Revenue Service. South African case law is dealt wit in terms of enforcement of Bargaining Council agreements, commission-earning persons, payment for services rendered, the intention of the parties and the identity of the true employer. The emergence of the dependent contractor is also addressed. This form of worker normally falls outside of the protection of labour legislation and social security. Amendments have been proposed to various statutes to remedy the situation in South Africa. A final aspect that is dealt with is that of vicarious liability. The applicability of this aspect lies in the liability of the employer for damages inflicted by the employee.
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  • Date Issued: 2001

The goddess, the witch and the bitch : three studies in the perception of women

  • Authors: Hare, Nicola Tracy
  • Date: 2001
  • Subjects: Feminism in literature , Women's rights in literature , Feminism and literature , Patriarchy in literature
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:10986 , http://hdl.handle.net/10948/278 , Feminism in literature , Women's rights in literature , Feminism and literature , Patriarchy in literature
  • Description: In the minds of many people all over the world, women are ‘second class citizens’, standing accused of the downfall of mankind ever since Eve allegedly ate the apple. Even amongst those who do not openly denigrate women, there are many who do so in other, more subtle ways even if they are unaware of it. This study proposes to challenge such a view of women by exposing the ways in which perceptions of women are constructed by society, which frequently wants to maintain the status quo of male dominance. This study employs a feminist approach in examining this gynocentric theme, along with cultural studies which, with its focus on power relations and ways of decentring power structures, is also clearly of use. In addition, this multidisciplinary approach of cultural studies offers the possibility of studying literary texts as well as popular culture. Three specific time periods are examined, with a view to uncovering negative perceptions of women and ways that women can resist such attempts to control them. In chapter one, the focus turns to contemporary perceptions of prehistoric women and the ways that so-called ‘objective’ science has failed to represent women accurately. Similarly, ‘objective’ accounts of Goddess-worship – which frequently fail to examine this phenomenon adequately – are revisited. Alice Walker’s The Temple of My Familiar (1989) is discussed as a text which acts as a site of resistance to societally-informed perceptions. Chapter two continues this investigation by turning to the concept of the witch and its maligned association with women. Woman and witchcraft, having been associated for centuries, are investigated as a pairing which frequently results because iii of attempts to control women by androcentric society. In such situations, the practising of witchcraft can actually become a form of resistance to patriarchy. The pernicious effect of society’s need to purge itself – by witch hunts – of witches is also investigated. The Devil’s Chimney (1997) by Anne Landsman and “The prophetess” (1994) by Njabulo S. Ndebele are discussed as texts which examine fictionalised South African versions of this phenomenon. Sinead O’Connor, the Irish singer, is the ‘bitch’ discussed in chapter three. She is examined as a woman who offers strong and on-going resistance to patriarchal ways of thinking which would ‘box’ women in. This singer refuses to accept societal roles which are offered to women and so offers means of resistance to patriarchy, many of which are discussed in this chapter. This study concludes that it is the responsibility of women to resist patriarchy and to define roles for themselves. The three chapters examine various means of resistance and offer women insight into the forms of opposition they themselves can take.
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  • Date Issued: 2001

The right of the HIV/AIDS patient to treatment

  • Authors: Hoffmann, Toinette
  • Date: 2001
  • Subjects: AIDS (Disease) -- Patients -- Legal status, Laws, etc. -- South Africa , Hiv-positive Persons -- Legal status, Laws, etc. -- South Africa , AIDS (Disease) -- Government policy -- South Africa , AIDS (Disease) -- Treatment , AIDS (Disease) -- Social aspects
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:11042 , http://hdl.handle.net/10948/277 , AIDS (Disease) -- Patients -- Legal status, Laws, etc. -- South Africa , Hiv-positive Persons -- Legal status, Laws, etc. -- South Africa , AIDS (Disease) -- Government policy -- South Africa , AIDS (Disease) -- Treatment , AIDS (Disease) -- Social aspects
  • Description: The objective of this treatise is to establish whether a right to social security exists in South Africa, which would entitle HIV positive persons in South Africa citizens to medical care. A study was made of various articles in journals and on the Internet to determine the South African government's policy on a right to social security and to providing medical treatment. It was found that South Africa lacks an integrated, holistic approach to social security and does not guarantee the right to social security, merely the right to have access to social security. The same was found with the right to medical care. Although there seems to be a general right to medical care which extends to and includes HIV-positive patients, the state merely guarantees the right to apply for medical treatment but does not guarantee the granting thereof. It is submitted that the Department of Health's refusal to implement a vertical transmission prevention programme and the failure to offer treatment as an alternative, for whatever reason, is "penny wise and pound foolish". In the long run more money is spent dealing with pediatric AIDS. It was further found that although the government attempted to lay a groundwork with the formulation and acceptance of the national AIDS plan, the successful implementation thereof is seriously hindered due to the lack of inter- and intra-departmental collaboration, essential health services and funding.
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  • Date Issued: 2001

"Effulgent in the firmament" the politics of representation and the politics of reception in South Africa's 'poetry of commitment', 1968-1983

  • Authors: Mde, Vukani
  • Date: 2002
  • Subjects: South African literature -- Black authors -- History and criticism , Politics and literature -- South Africa -- History -- 20th century , Literature and state -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:10987 , http://hdl.handle.net/10948/288 , South African literature -- Black authors -- History and criticism , Politics and literature -- South Africa -- History -- 20th century , Literature and state -- South Africa
  • Description: This dissertation re-examines an era in the production and reception of English language poetry in South Africa by black writers. Intellectually the 1970's was the Black Consciousness phase of South African history and very few aspects of life in the country were untouched by the intellectual movement led by Steve Biko and other young black student leaders. The aesthetic and literary output of the time, like all other facets of South African life, exhibited the influence and pressures brought to bear by Black Consciousness. Moreover, the Black Consciousness poets introduced the most vibrant and innovative phase for English language poetry produced in South Africa. It is my contention, however, that such vibrancy and innovation has consistently been compromised by unsympathetic, often hostile, and almost-always ill-informed criticism. The dissertation offers a critique of the academic and journalistic practice of criticism in South Africa. I argue that critical practice in South Africa has been engaged throughout the twentieth century in the discursive enforcement of ‘discipline’. In his Discipline and Punish (1977) the French post-structuralist philosopher Michel Foucault demonstrated how power is wielded against oppressed/suppressed groups through self regulated proscriptions, and argued that power is a discursive rather than a corporeal phenomenon. My dissertation follows Foucault in reading the critical reception of Black Consciousness poetry as the practice of disciplinary power. The dissertation also engages critically with the poetry of Oswald Mtshali, Mongane Serote and Sipho Sepamla, and argues that their work is the inscription of black subjectivity into the literary and cultural mainstream. It situates their work within wider 6 societal debates and definitions of ‘blackness’. In this regard use is made again of Michel Foucault’s insights and methodology of discourse analysis as shown in The Archaeology of Knowledge (1972). I argue that Oswald Mtshali’s work is a failed attempt at a dissection of apartheid and colonialism from a broadly Christian and humanist perspective. In my reading of Mongane Serote I explore the relationship between women’s bodies and the practice of representation. It is my contention that Serote is most concerned with claims of belonging, and this is shown through his extensive use of the trope of ‘Mother’. My discussion of the poetry of Sipho Sepamla focuses on language and (self- )representation, particularly the use of practices of naming in constructing subjectivity. My contention is that Sepamla ultimately abandons attempts at representation in favour of oppositional self-construction in language. In the concluding chapter I defend the thesis that the politics of discipline have prevented the broad critical establishment from gaining access to these discursive constructions of blackness in the committed poetry of South Africa.
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  • Date Issued: 2002

A preliminary investigation into the patterns of performance on a computerized adaptive test battery implications for admissions and placement

  • Authors: Vorster, Marlene
  • Date: 2002
  • Subjects: Universities and colleges -- Admission , Advanced placement programs (Education) , Computer adaptive testing , Universities and colleges -- Entrance requirements
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:11030 , http://hdl.handle.net/10948/285 , Universities and colleges -- Admission , Advanced placement programs (Education) , Computer adaptive testing , Universities and colleges -- Entrance requirements
  • Description: The fallibility of human judgment in the making of decisions requires the use of tests to enhance decision-making processes. Although testing is surrounded with issues of bias and fairness, it remains the best means of facilitating decisions over more subjective alternatives. As a country in transition, all facets of South African society are being transformed. The changes taking place within the tertiary education system to redress the legacy of Apartheid, coincide with an international trend of transforming higher education. One important area that is being transformed relates to university entrance requirements and admissions procedures. In South Africa, these were traditionally based on matriculation performance, which has been found to be a more variable predictor of academic success for historically disadvantaged students. Alternative or revised admissions procedures have been implemented at universities throughout the country, in conjunction with academic development programmes. However, it is argued in this dissertation that a paradigm shift is necessary to conceptualise admissions and placement assessment in a developmentally oriented way. Furthermore, it is motivated that it is important to keep abreast of advances in theory, such as item response theory (IRT) and technology, such as computerized adaptive testing (CAT), in test development to enhance the effectiveness of selecting and placing learners in tertiary programmes. This study focuses on investigating the use of the Accuplacer Computerized Placement Tests (CPTs), an adaptive test battery that was developed in the USA, to facilitate unbiased and fair admissions, placement and development decisions in the transforming South African context. The battery has been implemented at a university in the Eastern Cape and its usefulness was investigated for 193 participants, divided into two groups of degree programmes, depending on whether or not admission to the degree required mathematics as a matriculation subject. Mathematics based degree programme learners (n = 125) wrote three and non-mathematics based degree programme learners (n = 68) wrote two tests of the Accuplacer test battery. Correlations were computed between the Accuplacer scores and matriculation performance, and between the Accuplacer scores, matriculation performance and academic results. All yielded significant positive relationships excepting for the one subtest of the Accuplacer with academic performance for the non-mathematics based degree group. Multiple correlations for both groups indicated that the Accuplacer scores and matriculation results contribute unique information about academic performance. Cluster analysis for both groups yielded three underlying patterns of performance in the data sets. An attempt was made to validate the cluster groups internally through a MANOVA and single-factor ANOVAs. It was found that Accuplacer subtests and matriculation results do discriminate to an extent among clusters of learners in both groups of degree programmes investigated. Clusters were described in terms of demographic information and it was determined that the factors of culture and home language and how they relate to cluster group membership need further investigation. The main suggestion flowing from these findings is that an attempt be made to confirm the results with a larger sample size and for different cultural and language groups.
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  • Date Issued: 2002

The concurrent jurisdiction of the Labour Court and the High Court

  • Authors: Wagener, Pieter Cornelius
  • Date: 2002
  • Subjects: South Africa. High Court , South Africa. Labour Court , Exclusive and concurrent legislative powers -- South Africa , Law, Interpretation and construction
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:11051 , http://hdl.handle.net/10948/286 , South Africa. High Court , South Africa. Labour Court , Exclusive and concurrent legislative powers -- South Africa , Law, Interpretation and construction
  • Description: An overview is given of the difficulties surrounding the concurrent jurisdiction of the Labour Court and High Court The main categories of the jurisdictional dispute are identified and systemised. The main branches are those of statutory overlap and interpretation of statutes. Statutory overlap concerns matters remaining from the industrial court era, urgent applications, delict and law of contract. Statutory interpretation mainly involves the interpretation of provisions in the Bill of Rights of the Constitution. An overview of the principles of jurisdiction with respect to the different courts, as well as a brief historical review of the development of such jurisdiction is given. Particular attention is given to the role of fundamental rights in the Constitution. Broad principles are identified whereby the difficulties may be addressed.
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  • Date Issued: 2002

The effect of nutrient levels and ratios on the growth of Microcystis aeruginosa and microcystin production

  • Authors: Sember, Craig Stewart
  • Date: 2002
  • Subjects: Microcystis aeruginosa -- Toxicology , Nitrates , Microcystins
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11076 , http://hdl.handle.net/10948/287 , Microcystis aeruginosa -- Toxicology , Nitrates , Microcystins
  • Description: This study reports the findings on the effect of nitrates and phosphates on the biomass and toxin production of various strains of the unicellular non-nitrogen fixing cyanobacterium, Microcystis aeruginosa. The occurrence of blooms of Microcystis aeruginosa and microcystin in freshwater impoundments across the globe has been on the increase lately due to increased levels of eutrophication, resulting in human and animal deaths and illness, as well as drinking and recreational water foulment. A range of environmental factors have been shown to effect growth and microcystin production. Existing literature however is somewhat contradictory as to the effects of these physical and chemical factors on toxin production. Therefore Microcystis aeruginosa strains were cultured under batch and continuous conditions to determine the effect of nitrate and phosphate concentrations and ratios on biomass and toxin production. Cultures were analysed with regards to internal nutrient stores, biomass production, nutrient depletion, photosynthetic efficiency and microcystin production. Results showed that microcystin production correlated to growth rate, photosynthetic efficiency and internal nitrogen stores and that an optimal N:P ratio was associated with microcystin levels, growth rate and photosynthetic efficiency. Results therefore led to the conclusion that the nitrogen, carbon, and phosphate balance within the cell is closely associated with microcystin production. Whether or not microcystin is produced to maintain this balance or produced as a function of this balance remains to be determined.
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  • Date Issued: 2002

The effect of selenium in the detoxification of the microcystin hepatotoxins

  • Authors: Downs, Kerry
  • Date: 2002
  • Subjects: Cynaobacterial toxins , Microcystins , Selenium
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11070 , http://hdl.handle.net/10948/284 , Cynaobacterial toxins , Microcystins , Selenium
  • Description: Blooms of cyanobacteria have been known to cause illness in humans and death in wild and domestic animals. One of the toxins produced by cyanobacteria is microcystin, which is a potent hepatotoxin. Microcystin is taken up by bile acid transporters in the intestine and transported into the liver. After exposure to acute doses of microcystin, severe haemorrhage has been observed along with apoptotic and necrotic hepatocytes. The cytoskeletal structure of the hepatocytes is disrupted and oxidative stress is induced. Selenium, a known anti-oxidant, has been shown to induce increased activity of glutathione peroxidase. Glutathione peroxidase removes peroxides from cells protecting them from oxidative stress. This study set out to determine if selenium could play a role in preventing the damage to mice livers due to microcystin toxin. The protective role of selenium was explored in three main studies: in the first study, the ability of selenium to increase the survival time of mice exposed to a lethal dose of toxin was determined. In the second study the mice were exposed to sublethal chronic doses of toxin over 30 days. The ability of selenium to minimise liver damage under these conditions was determined. The final study investigated the mechanism of the protective effect of selenium. The results of the first study suggested that selenium could extend survival time. In the second study the selenium supplemented mice showed a reduction in the extent of the increase in liver weight and a decrease in the amount of lipid peroxidation induced compared to the mice that received only toxin. The histology of the selenium supplemented mice also showed a decrease in the severity and amount of morphological changes in the liver. The third study indicated that the protection shown by selenium might be mediated by an increase in the glutathione peroxidase (GPX) activity in selenium supplemented mice. This increase in GPX activity would increase the removal of the lipid hydroperoxides and prevent the damage they would cause in the cell. A further result indicated an increase in glutathione S-transferase in only the toxin control mice when compared to the selenium supplemented and control mice. ii In conclusion selenium offers protection against microcystin but further studies need to be done to provide statistically valid results to clarify the level of protection.
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  • Date Issued: 2002

The immobilization of Microcystis aeruginosa PCC7806 on a membrane nutrient-gradostat bioreacator for the production of the secondary metobolites

  • Authors: Strong, Peter James
  • Date: 2002
  • Subjects: Microcystis aeruginosa , Myrocystins , Bioreactors
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:11083 , http://hdl.handle.net/10948/283 , Microcystis aeruginosa , Myrocystins , Bioreactors
  • Description: A module and an inoculation technique were developed that would allow for the efficient immobilization of Microcystis aeruginosa PCC7806 on a synthetic membrane. A variety of module types, membranes (ceramic, tubular polyethersulfone and externally skinless polyethersulfone capillary membrane), and methods of immobilization (adsorption, pressure filtration and a developed technique that involved drying a cell slurry on a membrane) were assessed. The morphological properties that affected the immobilization of Microcystis aeruginosa PCC7806, as well as the effects of immobilization upon cell morphology were assessed. Cells in the stationary growth phase, which had a well-developed extra-cellular polysaccharide layer and no gas vesicles, were optimal for immobilization. Microcystin production under immobilized conditions was assessed under different nitrate concentrations, light intensities, biofilm thickness and immobilization times. Additional work included assaying for Microcystin production of two airlift-grown cultures under a high light intensity and complete nutrient deprivation and the inoculation of a ceramic membrane. An immunological technique was used to elucidate where toxin production was greatest within a biofilm immobilized upon an externally skinless polyethersulfone capillary membrane. The externally skinless polyethersulfone capillary membrane was evaluated to assess homogeneity and the physical differences between membrane batches that led to the erratic, incomplete biofilm formation, as a biofilm of a constant thickness could not be immobilized. Microcystis aeruginosa PCC7806 was exposed to a variety of solvents in order to permeabilize the cyanobacteria, as that would have enabled a truly continuous extraction process for the metabolite. FDA hydrolysis had to be optimized in order to use it as an indicator of cell viability. In addition a single-step extraction of Microcystin was attempted using live bacteria. A capillary membrane module, containing the externally skinless polyethersulfone capillary membrane, inoculated using pressure filtration, was the most efficient combination to establish a biofilm. Cells that were no longer actively dividing and that lacked buoyancy displayed superior immobilization to cells that were actively dividing and buoyant. The immobilized cells did produce Microcystin but in much lower concentrations to cells grown in an airlift culture. Biofilms grown with a higher nitrate concentration, a lower biofilm thickness and a lower light intensity had a higher specific microcystin content, while biofilms with a higher nitrate concentration a lower light intensity and a longer growth period displayed the a greater toxin production per mm2 of membrane. Microcystin occurred at its highest concentration in cells just above the pore opening. The diffusion of nutrients occurred relatively quickly to the outside layers of the biofilm, with a true gradient being established laterally from these nutrient veins that were above the pores. Permeabilization of the cells proved unsuccessful, as cells that remained viable did not release the intracellular compound into the surrounding medium.
  • Full Text:
  • Date Issued: 2002
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