Submitted in fulfillment of the requirements for the degree of Doctor of Philosophy: Biotechnology, Durban University of Technology, Durban, South Africa, 2015. / Photodynamic therapy (PDT) is emerging as a viable alternative to invasive anti-cancer treatment regimens such as surgery, chemotherapy or radiotherapy. A series of metal – based phthalocyanine complexes have been discovered that may be used as a drug or photosensitizer in photodynamic therapy for the treatment of cancers. During photodynamic therapy the photosensitizer is administrated intravenously or topically to the patient before laser treatment at an appropriate wavelength is delivered to the cancerous site to activate the photosensitizer. The activated photosensitizer will react with oxygen typically present in the cancerous tissue to produce reactive oxygen species for the eradication of the cancerous tissue. This is the first study where gallium (GaPcCl), indium (InPcCl) and iron (FePcCl) Pc chloride complexes were used for photodynamic research. These metal – based phthalocyanine complexes were investigated using different cancer cell lines (Caco-2, MCF-7, melanoma and A549). Also, the baseline cellular uptake and photodynamic effect of these complexes were established on healthy normal cells (human fibroblast cells). Fluorescent spectrophotometry showed that all three photosensitizers accumulated in a time-dependent manner in Caco-2, MCF-7, melanoma and A549 cancer cells, as well as in healthy normal fibroblast cell in amounts which increased over a period of 24 hours, with emission peaking at 24 hours for all cell lines. Dark toxicity effects and photodynamic therapy efficacy were established with a MTT assay. High concentrations of inactive GaPcCl, InPcCl and FePcCl was toxic to Caco-2, melanoma, A549 and fibroblast cells. However, all three photosensitizers were in its inactive state at low and high photosensitizing concentrations were highly toxic to MCF-7 cancer cells. On the other hand, in vitro photodynamic therapy treatment with both low and high concentrations of GaPcCl, InPcCl and FePcCl were observed to be potently cytotoxic towards all four cancer cell lines upon exposure to laser light for 22 seconds (2.5 J/cm2), 39 seconds (4.5 J/cm2) and 74 seconds (8.5 J/cm2). These results revealed that all three photosensitizers reacts to photodynamic therapy in a concentration-dependent (photosensitizer) and dose-dependent (light dose/time) manner. At 24 hours after photodynamic therapy, the most effective treatment parameters were laser treatment for 74 seconds with FePcCl concentrations from 60 µg/ml - 100 µg/ml which resulted in 0% cell survival of Caco-2 cancer cells. A short laser treatment time of 74 seconds for activation of FePcCl (20 µg/ml) resulted in 0% cell survival of MCF-7 cancer cells. Similarly, FePcCl (40 µg/ml - 100 µg/ml) activated for 22 seconds, 39 seconds and 74 seconds resulted in 100% cell death of A549 cancer cells. Photodynamic therapy treatment with GaPcCl and InPcCl were very effective in reducing the cell viability of melanoma cancer cells. Healthy normal fibroblast cells survived in vitro photodynamic therapy treatment with all three photosensitizers much better than the cancer (Caco-2, MCF-7, melanoma and A549) cells. This confirms the previously reported results that photosensitizers such as phthalocyanines and its metal-based complexes preferentially accumulate in cancer cells than normal healthy cells. All three photosensitizers localized in mitochondria and lysosomes of the Caco-2, MCF-7 and A549 cancer cells. In melanoma cancer cells InPcCl also localized in the mitochondria and lysosome, but GaPcCl and FePcCl localized in mitochondria only. Apoptosis was identified via microscopical and flow cytometric investigations, as the dominant mode of cell death induced by GaPcCl, InPcCl and FePcCl mediated photodynamic therapy in cancer cell lines tested. Therefore, this study concludes that GaPcCl, InPcCl and FePcCl are effective photosensitizers for the in vitro PDT treatment of cancer cells. The effective in vitro PDT treatment for each cell line was dependent on the photosensitizer concentration and illumination period for each of the different photosensitizers. / D

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Ocean modeling is usually constrained by the lack of observed velocity data for the initial condition. The diagnostic initialization is widely used to generate velocity data as initial condition for ocean modeling. It integrates the model from known temperature (Tc), salinity (Sc) and zero velocity fields and holds (Tc, Sc) unchanged. After a period of the diagnostic run, the velocity field (Vc) is established, and (Tc, Sc, Vc) fields are treated as the initial conditions for the numerical modeling. During the diagnostic initialization period, the heat and salt 'source/sink' terms are generated at each time step. In this Thesis, the Princeton Ocean Model implemented to the South China Sea demonstrated extremely strong thermohaline sources and sinks generated by the diagnostic initialization. Such extremely strong and spatially non - uniform initial heating/cooling (salting/freshening) rates in the ocean model ma y cause drastic change in thermohaline and velocity fields initially (after the diagnostic run). There is a need to overcome such problems or find alternative methods as diagnostic initialization is extensively used. / Republic of Singapore Navy author.

M.Comm. (Economics) / Refer to full text

M.Com. (Economics) / This paper examines two issues: Firstly, it analyses the mismatch between the demand and the supply of engineers in South Africa (SA) and secondly, it investigates the availability of engineers (to serve per 100 000 people) in SA during the period 2000 - 2008. The study applied Analysis of Variance (ANOVA) together with a battery of Matrix tools. The findings of this study revealed that both the demand and the supply of engineers were rising but at varying rates. Results from the mismatch index demonstrated that the supply index has marginally improved between 2000 and 2008. This discovery could be relatively ascribed to the surge in engineering graduates from technikons. Furthermore, the study discovered that the trend of the mismatch index shows a '. negative mismatch between the demand and the supply of engineers in SA. This may imply that the demand for engineers has been satisfied only by the supply from universities between 2000 and 2008. In the light of the shortage of engineers, it was discovered that the need arose considerably between 2000 and 2008, since population growth escalated more rapidly than the supply of engineers. Based on these findings the following recommendations are suggested: In the short to medium term, the South African government should embark upon strategies aimed at curbing the exodus of its skilled and experienced engineers. This could be achieved through the creation of congenial working environments for local engineers. Financial incentives, in the form of competitive remuneration, should also be considered. In the same vein, the South African government needs to re-examine its labour laws, in order to make significant adjustments which may enable the country to attract expatriate engineers, without lengthy delays. In the long run, the South African government needs to broaden the capacity of both secondary schools and universities in terms of the production of competent Science teachers and lecturers. In this regard, the South African government could send its Mathematics and Science teachers, lecturers and educators to countries that are leading these fields for quality training. The most likely positive outcome of this could be the increased number of competent Mathematics and Science educators in South Africa, which will in turn translate into well-equipped matriculants meeting the tougher demands of the Engineering degree programmes at both technikon and university levels.

M.Comm. / In this study the role and function of an Industrial Strategy in South Africa was investigated within the context of the Macroeconomic Strategy for rebuilding and restructuring the economy through growth, employment and redistribution and keeping in line with the goals set out. in the Reconstruction and Development Programme. The findings of the research can be summarised as follows: The industrial strategies of the past were seen as a mechanism to protect South Africa's local industries and to support the policy of import substitution. Against this background the current policy documents guiding South Africa's industrial strategy were evaluated. From this it was gathered that the change from a demand side to a supply side industrial strategy is in line with the above policy documents. The industrial strategy is ideally suited to provide a development service contributory to all aspects of economic development (namely the institutional, economical, physical and social aspects thereof). International experience and development information gathered should be used extensively as a continuous planning and evaluation instrument as this will ensure that the industrial strategy is relevant, accountable and influential. In view of the magnitude of economic development challenges in South Africa (inter alia directed towards overcoming the inequalities of the past) the research conclusions reached were a) that the industrial strategy has indeed a rightful place as part of the bigger macro-economic strategy in South Africa, but b) for the industrial strategy to play its economic role to the full, the strategy must keep in line with international developments.

The purpose of this study is twofold. Firstly, business cycle theories have been developed as early as 1911 (Shumpeter). These theories are well researched and well documented, and all of these theories concentrate on the real sector. South Africa is an emerging market and since 1994 the country has liberalized its market, a process that holds advantages and disadvantages. This emerging market status as well as the relative size of imports and exports to GDP in South Africa, makes the country very vulnerable to changes in the world economy. Examples of this are the contagion from Asia in 1997, the Russian crisis in 1998, and the impact of September 11 in the US on the South African economy. Business cycles also have changed over the years; they are less volatile and more synchronized over the world and the financial markets play a more important role. This is another reason why it might be useful to identify a financial cycle and investigate its relationship with the real cycle. The SARB (South African Reserve Bank) has some financial indicators in its leading indicator but the latter is mainly driven by real indicators. The financial cycle identified uses the equity market, the capital market and the domestic financial market as components. All of the determinants of these three components are available at a higher frequency than the GDP growth (our proxy for the business cycle); therefore the financial cycle can be used as a leading indicator incorporating international and domestic financial events. Secondly, an ongoing debate in business cycle research is the question of a stable economy (business cycle) influenced by exogenous shocks or an unstable economy with an endogenous business cycle (Classical vs. Keynesian view). This issue will be addressed by modelling the business cycle with a linear as well as a non-linear model. Linear models are usually used to demonstrate exogenous shocks on the business cycle, whereas nonlinear models have more of an endogenous assumption regarding the business cycle. Non-linear models learn over time and adjust to the new level of peaks and troughs and can therefore predict turning points more accurately. This suggests that business cycles have changed since 1960: they became less volatile, more synchronized across the world and the amplitude of peaks and troughs is lower. Because of these characteristics it would be useful to fit a non-linear model to the business cycle. However, exogenous shocks cannot be totally ignored – especially in an emerging market such as South Africa. The STAR (smooth transition autoregressive) model makes room for a linear and a non-linear component, and can over time determine if there is only a linear or non-linear component or sometimes both. The results of this study support the structural or institutional view. They believe economic fluctuations are caused by various structural or institutional changes. Adherents to this view do not believe that the market system is inherently stable or systematically unstable (Classical vs. Keynesian view). They focus on structural changes and unpredictable events. They do not have set ideas on economic policy. According to them the appropriate policy will vary from time to time as circumstances change. / Prof. L. Greyling

D.Com. (Economics) / Please refer to full text to view abstract

M.Com. (Economics) / Please refer to full text to view abstract

M.A. / The purpose of this study is to examine structural unemployment in the post apartheid South Africa and propose possible policy options to reduce structural unemployment in the new South Africa. In coming to some possible solutions, it is necessary to consider the South African labour market before and after the elections in 1994 when the Apartheid struggle was ended in a formal and legitimate manner. It is also necessary to research the dilemma of structural unemployment in South Africa and search for possible solutions to the problem by looking at current government policy and other views from the different stakeholders in the economy. It is only through this process that one can start coming to some kind of conclusion as to possible measures to reduce structural unemployment in the post-Apartheid South Africa. This study should by no means be considered as the answer to the problem of unemployment in South Africa, but only acts as an introductory study into the problem of rising structural unemployment in the country.