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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Perceptions of the financial benefits of organic agriculture in South Africa

24 July 2013 (has links)
M. Comm. (Financial Management) / The threats of climate change have become too serious to ignore. It has thus become necessary for humans to consider the environmental impact of their decisions, including the decision regarding which agricultural practices to use. Organic agriculture is believed to be a mitigating factor when it comes to climate change. It has the additional benefit of contributing to human health due to the fact that the consumption of organically grown food reduces exposure to potentially harmful pesticides. In this study the perceptions of organic farmers regarding the benefits and disadvantages of organic agriculture, from a financial and nonfinancial perspective, were gauged. A convenience sample of 26 farmers was obtained. The utility of a convenience sample was necessary due to the unavailability of a complete database of organic farms in South Africa. The results of the study indicated that the non-financial benefits of organic agriculture were considered to be the most important consideration for the decision to farm organically irrespective the high input cost associated with it. Indeed, high input costs were identified as the greatest disadvantage of organic agriculture. The results of the study contribute to the existing body of knowledge of the trade-off between the financial and non-financial benefits of organic agriculture in South Africa.
272

Die aard van omvang van Suid-Afrika se eksterne handel soos gemeet aan die hand van die land se fisiese hawefasiliteite

03 September 2015 (has links)
D.Com. / Please refer to full text to view abstract
273

Predicting recessions in South Africa : a comparison of the predictive accuracy of linear and non-linear models

14 July 2015 (has links)
M.Com. (Econometrics) / This dissertation investigates the ability of different models to predict a recession in South Africa (SA) by choosing a best performing model based on the smallest prediction errors made by the models. One of the purposes of using econometric models is to predict a recession, with the goal to uncover the probability of a recession or real GDP growth rate as accurately as possible. Although linear and non-linear models prediction strength is frequently compared, none of the studies within SA compare the prediction ability of the four models used in this dissertation. The intent of this research is to ascertain the best prediction model for SA so as to advise policy makers on the soundest model to use if there is suspicion that SA could enter a recession in the future due to global and domestic uncertainty. This is done by comparing the prediction ability of the linear ARIMA, VAR and ARMV models’ and non-linear dynamic probit model; thereby contributing toward the standing literature. It is verified which model outperforms the others in predicting future real GDP growth by comparing the Mean-Square-Error (MSE), Mean-Absolute-Error (MAE) and RMSE percentage. The importance of predicting real GDP growth is accentuated so that policy makers are in the position to develop or apply policies that can stimulate growth in the economy, should a recession occur. By adding dynamics to the system, predictions are improved. The linear VAR model outperforms the other linear and non-linear model based on the RMSE, MAE and RMSE percentage.
274

Enkele bedryfsekonomiese aspekte van koöperatiewe garages in die Wes-Transvaal

28 October 2015 (has links)
M.Com. (Business Economics) / Please refer to full text to view abstract
275

'n Ekonomies-politieke evaluering van Suid-Afrika se invoertariefbeleid op grond van die teorie van effektiewe tariefbeskerming

29 October 2015 (has links)
D.Phil. (Economics) / Please refer to full text to view abstract
276

In vitro photodynamic effect of gallium, indium and iron phthalocyanine chloride on different cancer cell lines

Maduray, Kaminee January 2015 (has links)
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
277

'n Empiriese ondersoek na die ervaarde rolkonflik en stres van projekspanlede

05 February 2014 (has links)
M.Comm. (Economics) / Refer to full text
278

An economic analysis of the mismatch between demand and supply of engineers in South Africa

14 January 2014 (has links)
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.
279

'n Ontleding van Suid-Afrika se nywerheidstrategie in die negentigs

13 September 2012 (has links)
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.
280

Modelling the business cycle of South Africa: linear vs non-linear methods.

11 June 2008 (has links)
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

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