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Propagating some commonly-used South African medicinal plants with compost and vermitea

  • Authors: Faulconbridge, Steven Craig
  • Date: 2013
  • Subjects: Medicinal plants -- Propagation -- South Africa , Compost -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10736 , http://hdl.handle.net/10948/d1020316
  • Description: The use of many of South Africa’s medicinal plants has shown marked increase with over 27 million users in South Africa alone. Most plants are still being unsustainably wild-harvested, a major concern for biodiversity conservation. Commercial interest in certain more commonly-used species has increased, with potential to cultivate medicinal plants on a more sustainable basis. Focus has shifted from conventional use of synthetic fertilisers, pesticides and fungicides to more organic methods of plant propagation. Aqueous extract derived from earthworm composted food waste (vermitea) was used to study the germination and rooting success of selected species. Also survival and growth performance of selected plants grown in a medium amended with commercial NPK fertiliser was compared to those grown in the same medium amended with compost and to those grown in the same medium amended with compost with weekly applications of vermitea. No change in germination success was noted. Vermitea showed promising results on the rooting of cuttings. The application of NPK improved growth performance (biomass) significantly for all species tested. However, they had lower root:shoot ratios as well as lower survival rates compared to plants under the compost and compost/vermitea treatments. The improved survival of these plants highlights the potential of these organic treatments on the propagation of selected medicinal plants.
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  • Date Issued: 2013

Forced degradation studies of clobetasol 17‐propionate in methanol, propylene glycol, as bulk drug and cream formulations by RP‐HPLC

  • Authors: Fauzee, Ayesha F , Walker, Roderick B
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/184005 , vital:44154 , xlink:href="https://doi.org/10.1002/jssc.201200969"
  • Description: A rapid, simple, stability-indicating forced degradation study of clobetasol 17-propionate was conducted using RP-HPLC. The method was used to analyze clobetasol 17-propionate in methanol, propylene glycol, and a cream formulation. Isocratic elution of clobetasol and its degradation products was achieved using a Nova-Pak® 4 μm C18 150 mm × 3.9 mm id cartridge column and a mobile phase of methanol: water (68:32 v/v) at a flow rate of 0.9 mL min−1. Quantitation was achieved with UV detection at 239 nm. Nondegraded clobetasol was eluted at a retention time of 6.0 min. Clobetasol 17-propionate was subjected to different stress conditions viz., acidic, basic, heat, oxidation, light, and neutral hydrolysis. The greatest degradation occurred under strong base and oxidative conditions. Strong base-degraded clobetasol produced additional peaks at retention times of 1.8, 4.0, 5.0, and 8.0 min and clobetasol oxidation degradation peaks eluted at 2.2 and 24 min. Complete validation was performed for linearity, accuracy, and precision over the concentration range 0.15–15 μg mL−1. All data were analyzed statistically and this RP-HPLC method proved to be accurate, precise, linear, and stability indicating for the quantitation of clobetasol 17-propionate in methanol, propylene glycol, and cream formulations.
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  • Date Issued: 2013

Adsorption and separation of platinum and palladium by polyamine functionalized polystyrene-based beads and nanofibers

  • Authors: Fayemi, Omolola E , Ogunlaja, Adeniyi S , Kempgens, Pierre F M , Antunes, Edith M , Torto, Nelson , Nyokong, Tebello , Tshentu, Zenixole R
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/241694 , vital:50961 , xlink:href="https://doi.org/10.1016/j.mineng.2013.06.006"
  • Description: Adsorption and separation of platinum and palladium chlorido species (PtCl62- and PdCl42-) on polystyrene beads as well as nanofibers functionalized with ammonium centres based on ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA) and tris-(2-aminoethyl)amine (TAEA) are described. The functionalized sorbent materials were characterized by microanalysis, SEM, XPS, BET and FTIR. The surface area of the functionalized fibers was in the range 69–241 m2/g while it was 73–107 m2/g for the beads. The adsorption and loading capacities of the sorption materials were investigated using both the batch and column studies at 1 M HCl concentration. The adsorption studies for both PtCl62- and PdCl42- on the different sorbent materials fit the Langmuir isotherm with R2 values >0.99. The highest loading capacity of Pt and Pd were 7.4 mg/g and 4.3 mg/g respectively for the nanofiber sorbent material based on ethylenediamine (EDA) while the beads with ethylenediamine (EDA) gave 1.0 mg/g and 0.2 mg/g for Pt and Pd respectively. Metals loaded on the sorbent materials were recovered by using 3% m/v thiourea solution as the eluting agent with quantitative desorption efficiency under the selected experimental conditions. Separation of platinum from palladium was partially achieved by selective stripping of PtCl62- with 0.5 M of NaClO4 in 1.0 M HCl while PdCl42- was eluted with 0.5 M thiourea in 1.0 M HCl. Separation of platinum from iridium and rhodium under 1 M HCl concentration was successful on triethylenetriamine (TETA)-functionalized Merrifield beads. This material (M-TETA) showed selectivity for platinum albeit the low loading capacity.
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  • Date Issued: 2013

The development of platinum and palladium-selective polymeric materials

  • Authors: Fayemi, Omolola Esther
  • Date: 2013 , 2013-05-03
  • Subjects: Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4287 , http://hdl.handle.net/10962/d1002964 , Polymers , Platinum , Palladium , Adsorption , Sorbents , Nanofibers , Amines , Nanoparticles
  • Description: The adsorption and separation of platinum(IV) and palladium(II) chlorido species (PtCl₆²⁻ and PdCl₄²⁻) on polystyrene-based beads and nanofibers as well as silica microparticles functionalized with polyamine centres derived from ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetriamine (TETA) and tris-(2-aminoethyl)amine (TAEA) is described. The functionalized sorbent materials were characterized by using microanalysis, SEM, XPS, BET and FTIR. The nanofiber sorbent material functionalized with ethylenediamine (F-EDA) had the highest loading capacity which was attributed to its high nitrogen content (10.83%) and larger surface area (241.3m²/g). The adsorption and loading capacities of the sorption materials were investigated using both the batch and column studies in 1 M HCI. The adsorption studies for both PtCl₆²⁻ and PdCl₄²⁻ on the polystyrene-based sorbent materials fit the Langmuir isotherm while the silica-based sorbents fitted the Freundlich isotherm with R² values > 0.99. In the column experiment the highest loading capacity of Pt and Pd were 7.4 mg/g and 4.3 mg/g respectively on the nanofiber sorbent material based on ethylenediamine (EDA). The polystyrene and silica-based resins with triethylenetetramine (TETA) functionality (M-TETA and S-TETA) showed selectivity for platinum and palladium, respectively. Metal chlorido complexes loaded on the sorbent materials were recovered by using 3% m/v thiourea solution as teh eluting agent with quantitative desorption efficiency under the selected experimental conditions. The separation of platinum from palladium was partially achieved by selective stripping of PtCl₆²⁻ with 0.5 M of NaClO₄ in 1.0 M HCI with PdCl₄²⁻ was eluted with 0.5 M thiourea in 1.0 M HCI. The selectivity of the M-TETA and S-TETA sorbent materials was proved by column separation of platinum(IV) and palladium(II), respectively, from synthetic solutions containing iridium(IV) and rhodium(III). The loading capacity for platinum on M-TETA was 0.09 mg/g while it was 0.27 mg/g for palladium on S-TETA. , Acrobat PDFMaker 10.1 for Word , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 2013

Perceptions on ante-mortem welfare, quantitation of pain and pregnancy biomarkers, muscular fibre architecture and quality of Dohne Merino offal

  • Authors: Fayemi, Peter Olutope
  • Date: 2013
  • Subjects: Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Language: English
  • Type: Thesis , Doctoral , PhD (Animal Science)
  • Identifier: vital:11824 , http://hdl.handle.net/10353/d1007573 , Merino sheep , Slaughtering and slaughter-houses -- By-products , Biochemical markers , Meat -- Quality , Consumers' preferences , Cooking (Variety meats) , Livestock -- Transportation
  • Description: Sheep farming is practiced extensively in South Africa for its significant contributions to the livestock, wool and meat industries. The sheep farming sector in the country has approximately 13,800 farmers with commercial and communal sheep farmers making up 58 percent and 42 percent of the entire work force (Directorate of Agricultural Information Services, 2008). An estimate of 28.8 million sheep and flock size ranging between ≤ 50 and ≥ 1800 exist in various South African provinces. Although the national herd size is unevenly distributed provincially most of the herds are found in the Eastern Cape (30 percent) followed by the Northern Cape (25 percent), Free State (20 percent) and the Western Cape (11 percent) respectively (Agriculture, Forestry and Fisheries, 2011). Over twenty indigenous and locally developed sheep breeds are managed where about 69 percent of the land area is available for their grazing nation-wide (Campher et al., 1998; Palmer and Ainslie, 2006). Common among the indigenous breeds are the Afrikaner, Blackhead Persian, Blackhead Speckled Persian, Blinkhaar Ronderib, Damara, Karakul, Namaqua Afrikaner, Pedi, Redhead Persian, Redhead Speckled, Swazi and Zulu. The locally developed breeds include Dorper, Van Rooy and Merinos. The local breeds developed from Merinos consist of the Afrino, Dormer, Dohne Merino and South African mutton Merino (Hammond, 2000; Pranisha, 2004; Hinton, 2006; Sorma et al., 2012). All these sheep breeds are best suited for providing by-products such as wool, meat, hide, milk or a combination of products (Dave and Meadowcroft, 1996; Jensen, 2009). The indigenous and locally developed sheep were bred to meet the growing demand for its by-products (Peters et al., 2010). Expectedly, sheep farmers therefore, make use of the products from these sheep as a means of livelihood and sustenance of a viable local society (Cloete and Olivier, 2010).
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  • Date Issued: 2013

Academic freedom and the enclosure of knowledge in the global university

  • Authors: Federici, Sylvia
  • Date: 2013
  • Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/773 , vital:19989
  • Description: A discussion of 'academic freedom' is timely as everywhere, across the planet, this long fought-for principle is under siege. Trends, already emerging in Africa in the 1980s, are extending to every part of the world, contributing to what we can call 'a global enclosure of knowledge. ' This is the restriction of access to education to the 'happy few,' as knowledge and education are becoming commodified and profitability is becoming the sole logic by which the university is structured. Here I examine the most salient ways in which academic freedom is affected by these developments (with special reference to the United States) and, most important, how we can resist them. First, however, I consider what we mean by 'academic freedom,' since it is a concept that has been evolving, taking on new meanings, and is presently used with different connotations.
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  • Date Issued: 2013

When does a nation-level analysis make sense? ESD and educational governance in Brazil, South Africa, and the USA

  • Authors: Feinstein, Noah W , Jacobi, Pedro R , Lotz-Sisitka, Heila
  • Date: 2013
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/131645 , vital:36707 , http://dx.doi.org/10.1080/13504622.2013.767321
  • Description: International policy analysis tends to simplify the nation state, portraying countries as coherent units that can be described by one statistic or placed into one category. As scholars from Brazil, South Africa, and the USA, we find the nation-centric research perspective particularly challenging. In each of our home countries, the effective influence of the national government on education is quite limited, particularly in fringe and emerging areas of education such as Education for Sustainable Development (ESD) and Climate Change Education (CCE). This essay explores how nation-level comparisons are and are not useful for international research on ESD and CCE. We consider several layers of decentralized governance, but ultimately come to the conclusion that ESD governance in our respective countries is polycentric rather than decentralized. We discuss the implications of this idea for cross-national policy research on ESD and CCE.
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  • Date Issued: 2013

The effect of the Nelson Mandela Bay Stadium on surrounding house prices: a hedonic analysis

  • Authors: Fernandes, Gladys Nicola
  • Date: 2013
  • Subjects: Housing -- Prices -- South Africa -- Port Elizabeth , Stadiums -- Economic aspects -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:9026 , http://hdl.handle.net/10948/d1020216
  • Description: Sports facilities increasingly feature amongst the most expensive development projects world-wide. One such facility includes world-class stadia. Such facilities tend to commit a considerably large amount of a country's public funds to the project. This public expenditure on new stadia, and the required public taxation, may be economically justified if the benefits from the new stadia outweigh the costs. 15 May 2004 saw South Africa winning the bid to host the FIFA 2010 Soccer World Cup tournament. This mega-event was played in 10 stadia across nine chosen host cities. Five of these stadia were newly constructed, while the other five needed upgrading. Both South Africa's national government and local governments of host cities bore the expenses of the new stadia construction and the upgrading to the existing stadia. This amounted to a total public expenditure of R13.5295 billion on the stadia alone. The Nelson Mandela Bay Stadium on the banks of the North End Lake in Port Elizabeth was amongst the five newly constructed stadia costing R1.7 billion. Many international studies have been conducted to assess the impact of new stadia on the economies of host cities. One particular aspect which has received a lot of attention as far as empirical research is concerned is the impact of stadia on residential property prices (Carlino & Couslon, 2004; Davies, 2005; Tu, 2005; Coates & Humphreys, 2006; Ahlfeldt & Maennig, 2007, 2010; Dehring, Depken & Ward, 2007; Feng & Humphreys, 2008, 2012; Kavetsos, 2010; Ahlfeldt, Maennig & Scholz, 2010; Kiel, Matheson & Sullivan, 2010; Ahlfeldt & Kavetsos, 2011; Coates & Matheson, 2011). The majority of the studies conducted have indicated that the presence of a new stadium in an area has a significantly positive effect on surrounding house values that decays with distance from the facility. As no study has yet been done in South Africa to investigate the impact of the announcement of the construction of new stadia on nearby residential property values, this study examines, by means of the hedonic pricing model, the effect of the announcement to construct the Nelson Mandela Bay Stadium on the banks of North End Lake on adjacent residential property values. The study period for this study was 2004 - 2006. This time period captured the stadium announcement effect. The residential properties in North End that were traded at least once during the period 2004 to 2006 made up the target population. According to the South African Property Transfer Guide (SAPTG), a total of 417 property transactions (excluding repeat sales) took place over the study period (2004 - 2006). The 417 transactions were deemed to be the size of the target population and a list of 100 property transactions were used as the sampling frame. As the study period was from 2004 - 2006, it was necessary to adjust the market prices to constant 2006 prices. For this purpose, data from the Port Elizabeth and Uitenhage section of the ABSA house price indices were used so as to eliminate any inflationary effects on the property values over the study period. The results of the study revealed that the stadium has a statistically significant positive effect on adjacent residential properties situated within a 1 200 metres radius from the stadium. The average owner of a residential property in North End would be willing-to-pay between R10 7898 and R11 704.6 to be situated 435 metres closer to the stadium.
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  • Date Issued: 2013

Development and validation of in-process control test kits for biodiesel production

  • Authors: Fibi, Pumza Oscarine
  • Date: 2013
  • Subjects: Biodiesel fuels -- South Africa , Biomass energy -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10416 , http://hdl.handle.net/10948/d1012645 , Biodiesel fuels -- South Africa , Biomass energy -- South Africa
  • Description: The production of biodiesel from vegetable oils is not a new technology; it has been around since the 1950’s and both the research in terms of the different feedstock that can be used and the production of biodiesel has since been gaining momentum as there needs to be a new, sustainable and domestic alternative to petroleum fuels. These petroleum fuels pose enormous threats to the environment and therefore need to be replaced as they are mostly contributing to climate change and global warming not to mention the frequent price hikes which are crippling the South African economy. Biodiesel production using vegetable oils seems to be and is the future and a law has recently been passed which sanctions the production of biofuel locally.[1] South African fuel producers will instigate obligatory blending of fossil fuel with biofuel as the country moves to encourage investment in its biofuels sector. The production of biodiesel locally and the blending of biodiesel with other petroleum products will reduce the country’s dependence on imported fuel. The already established petrochemical companies like BP, Sasol and Engine are therefore mandated to purchase these biofuels if and when the biofuels meet the required South African National Standard (SANS) 1935 requirements. This is then where the challenge comes as most of these growing biofuel companies cannot afford to purchase testing equipment.The growing companiesthen discover upon completion of the biofuel manufacturing process that their product does not meet the required standard specification. The failure translates to a financial loss as the final product can possibly not be reworked. The aim of the project is then to assist these companies who are manufacturing biofuel, by providing them with in-house biofuel process methods which will allow for early detection, should there be a need to redo a step in the process and not wait until the completion of the production process. These in-house process-testing methods will range from pH determination, titration tests which will determine the soap content and the percentage free fatty acid content, water determination, density and visual testing. It is not cost-effective for these biodiesel manufacturers to send their samples for outsource testing as evidently the results obtained would be out of specification hence the need to provide these biodiesel manufacturers with in-house analytical testing techniques that will aid in monitoring of the biodiesel production.
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  • Date Issued: 2013

The effectiveness in the administration of the national school nutrition programme in King Williams Town in the Eastern Cape

  • Authors: Fili, Linda Phinx
  • Date: 2013
  • Subjects: School children -- Food -- South Africa -- King William's Town -- Administration , Children -- Nutrition
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9224 , http://hdl.handle.net/10948/d1020965
  • Description: Health and education are two important aspects of human capital and form the basis of an individual’s economic productivity in any country. In South Africa, hunger and malnutrition continue to hamper the health, quality of life and survival of school going children such that some children drop- out of school due to these socio-economic problems (Tomlinson,2007:2). The introduction of previous School Feeding Schemes to address the question of hunger and poverty within schools was mostly left in the 1980’s and 1990’s to charitable and Non-Governmental Organizations such as Operation Hunger and ITHUBA (Swartz, 2009:38). According to Perlman (1993:14) South Africa’s track record of child deaths was more than double that of any other country of similar income levels worldwide, due to the apartheid government deserting its responsibility of feeding the nation. The White Paper for the Transformation of Health System (1997: 125) had also stated that improving nutrition within the rural schools is an imperative and a sound economic investment which is politically rewarding. Nelson Mandela (1996:8) once said “Our children are our nation’s future. Prospects for development are seriously undermined by the kind of large scale deprivation of children that South Africa has experienced. On the other hand investing in their health, nutrition and education not only improves our children’s quality of life – the gains reverberate into the future generations. ” From April 1994, through the Reconstruction and Development Programme (RDP) the Government of National Unity under the leadership of Dr. Nelson Mandela identified the area of school feeding as a policy prime concern in redressing the imbalances and inequities of the past governments. Another initiative to redress the inequities of the past, was through the programme of Poverty Reduction which manifested itself in lack of income, lack of education and skills, lack of access to services and amenities and lack of ownership of land and housing (Public Service Commission, 2007.
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  • Date Issued: 2013

Exploring the challenges of income generating projects funded by the Department of Social Development at Kwa-Nobuhle, Uitenhage, in the Eastern Cape

  • Authors: Filita, Unathi Samora
  • Date: 2013
  • Subjects: Public investments -- South Africa -- Port Elizabeth , Economic development projects -- South Africa -- Port Elizabeth , Poverty -- South Africa -- Port Elizabeth -- Economic conditions
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9191 , http://hdl.handle.net/10948/d1020323
  • Description: Income generating projects represent one strategy adopted by the Department of Social Development to alleviate poverty. The purpose of this study is to explore challenges of an income generating project funded by the Department of Social Development in Kwa-Nobuhle, Uitenhage of the Eastern Cape Province of South Africa., A sample of thirty respondents was drawn from ten income generating projects funded by the Department of Social Development. The sampling method of this study was purposive sampling. Data was gathered through semi-structured questionnaires. Related literature has been reviewed that focuses on income generating projects for poverty alleviation. Various recommendations have been made on the findings of the study. The findings of the study indicated the need for regular visits from the officials of the Department, to conduct monitoring and evaluation. Project members also need training on financial management so they cannot mismanage their finances. The research findings indicated clearly that strategies that were used by the Department were not effective enough to achieve desired goals of poverty alleviation.
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  • Date Issued: 2013

The criterion of justifiability as a ground for review following Sidumo v Rustenburg Platinum Mines (2007) 12 BLLR 1097 (CC)

  • Authors: Fischat, Herbert Robert James Falconer
  • Date: 2013
  • Subjects: Arbitration, Industrial -- South Africa , udicial review -- South Africa , Dispute resolution (Law) -- South Africa , Mineral industries -- South Africa -- Employees , Conflict of laws -- Labor laws and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:10246 , http://hdl.handle.net/10948/d1019792
  • Description: This treatise will focus on the review of labour arbitration awards provided for under the oversight of the Commission for Conciliation, Mediation and Arbitration (CCMA), bargaining councils, statutory councils, accredited private agencies and approved private arbitration tribunals. The general grounds of review applicable to the arbitration awards of the different bodies are set out. Thereafter the case of Carephone (Pty) Limited v Marcus NO & others (1998) 19 ILJ 1452 (LAC) is analysed and the core principles pertaining to the justifiability test are clarified for the first time in the forum of the Labour Appeal Court. The judicial rationale for the relevance and applicability of the test to CCMA arbitration proceedings and criticisms of the test are examined. The justifiability tests are only applicable to review proceedings in CCMA matters and not available to private arbitration review matters. There are however three approaches which are being suggested for the application of the justifiability tests to private arbitration review. Firstly, it is suggested that the Arbitration Act could be interpreted to include the justifiability test under the statutory review grounds. Secondly, the arbitration agreements could be interpreted to include an implied term that the arbitrator is under a duty to give justifiable awards. Finally, it can be submitted that the law should be developed by reading into all arbitration agreements the ability to arbitrators to give justifiable awards. Since the judgment of Sidumo v Rustenburg Platinum Mines [2007] 12 BLLR 1097 (CC) various critical questions arose in relation to the interpretation and application for the purpose of dealing with subsequent review applications. Firstly, this research paper will seek to establish whether the courts in subsequent matters to the Sidumo judgment have interpreted reasonableness as a test or ground for review. Secondly the research paper will scrutinise case law whether the reviewing court is entitled to rely on and consider reasons other than those provided for by the commissioner in his award to determine inter alia, the reasonableness of his decision arrived at. The Constitutional Court in the Sidumo case rejected the so-called employer’s test, stating that ultimately the commissioner’s sense of fairness is what must prevail and not the employer’s view. Consequently an impartial determination whether or not a dismissal was fair is likely to promote labour peace amongst the labour force. The test arrived at by the Constitutional Court in the Sidumo case for determining whether a decision or arbitration award of a CCMA commissioner is reasonable, is a stringent test that will ensure that such awards are not easily interfered with. The question to be asked in determining whether there has been compliance with the standard is whether the decision of the commissioner is one which a reasonable decision maker could have reached. This approach will underpin the primary objectives of the Labour Relations Act which is the effective resolution of disputes. This finding will be apparent from important cases decided and discussed after the Sidumo landmark ruling.
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  • Date Issued: 2013

The medicinal plant Sutherlandia Frutescens regulates gene expression to reverse insulin resistace in rats

  • Authors: Fortuin, Melissa
  • Date: 2013
  • Subjects: Insulin resistance , Medicinal plants , Genetic regulation , Insulin resistance -- Animal models
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10349 , http://hdl.handle.net/10948/d1020823
  • Description: Obesity can lead to Type 2 Diabetes, both conditions increase in association with physical inactivity and high-energy diets, resulting in elevated blood glucose, decreased insulin sensitivity and increased insulin resistance. Sutherlandia frutescens (S.frutescens), an anti-diabetic plant, reverses and prevents insulin resistance in a rat model and human cell culture model. Gene expression analysis in hepatocyte cultures, identified genes down regulated in insulin resistance and up regulated by S.frutescens. These included genes encoding vesicle transporter proteins, hypothesised to be linked to hepatic lipid accumulation and lipid droplet formation during insulin resistance. The aim of this study was to investigate critical genes involved in lipid droplet formation, vesicle assembly and transport in high fat diet (HFD)-induced insulin resistant rat liver tissue during the development of insulin resistance and the reversal of these changes by S.frutescens. Rats were fed a low fat diet (LFD) or HFD supplemented with S.frutescens for 2, 4 and 8 weeks. Rats fed a HFD for 12 weeks developed insulin resistance, confirmed by plasma glucose and insulin levels (compared to normal controls). Groups of these rats were gavaged with S. frutescens (50mg/kg BW), Metformin (13mg/kg BW) or water for a further 4 weeks and starved for 12 hours, anaesthetized and blood removed by heart puncture. Liver was stored in RNA-Later™ for qRT-PCR and snap-frozen in liquid nitrogen for western blotting and confocal microscopy analysis. Changes in expression of vesicle transporter genes VAMP3 and NSF were analysed by qRT-PCR and changes in the protein expression by western blotting analysis. Proteins were localised within the liver by confocal immunohistochemistry using ZEN lite™ software. Statistical analysis was performed using One-Way ANOVA and unpaired t-test. mRNA gene expression of vesicle transport components VAMP3, NSF and SNAP25 showed relatively moderate changes with considerable individual variation within control or experimental groups. Uncorrelated changes in mRNA and protein products were found and may be due to differential regulation by siRNA. Proteins also showed altered staining patterns in high fat diet rats that reverted towards normal on S. frutescens treatment, potentially reflecting functional changes associated with transport of lipid-filled vesicles.
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  • Date Issued: 2013

Single-end reflectometric measurements of polarization-mode dispersion in single-mode optical fibres

  • Authors: Fosuhene, Samuel Kofi
  • Date: 2013
  • Subjects: Fiber optics , Polarization (Light) , Optical measurements
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/6280 , vital:21069
  • Description: In this thesis two novel single-end methods are applied to measure and characterize polarization mode dispersion in single mode optical fibres. Polarization mode dispersion (PMD) is an important factor negatively affecting the successful implementation of high speed long haul optical fibre networks operating at bit rates of 10Gb/s and above. PMD measurements are thus important for quality control during manufacturing and cabling processes. It is also useful for network operators planning to upgrade bitrates in existing networks to 10Gb/s and beyond. In an optical fibre link, sections with particularly high PMD may act to increase the entire PMD of the link. Identifying and replacing such sections can greatly reduce the PMD of the link. PMD measurements can be forward or single-end. In forward measurements, both ends of the fibre are used for input and detection. In single-end configuration, only one end of the fibre is used. For this reason, single-end measurements are more practical for the field where fibre ends are situated several kilometres apart. Single-end techniques can be implemented with a continuous wave for non-local PMD measurements (by Fresnel reflection). If a pulsed wave is used, local measurements can be achieved (by total power due to Rayleigh scattering). Two single-end schemes, one based on Fresnel reflection and the other due to Rayleigh scattering have been applied to measure non-local and local PMD of standard single mode optical fibres. For the non-local PMD measurements, the general interferometric technique (GINTY) was modified to operate in a round-trip configuration. In this configuration, the fibre was treated as a concatenation of two identical fibre segments. Three different sets of fibres were investigated, each set representing a particular mode coupling regime. For polarization maintaining fibres, (PMFs), with no mode coupling, a factor of two was found between forward and single-end measurements. For long single mode fibres in the long length regime, the factor was 1.4. For a combination of PMF and single mode fibres, a factor of 1.6 was obtained. The method which is accurate, repeatable, low cost and robust is very suitable for field applications. The second method is the polarization optical time domain reflectometric (P-OTDR) technique. This technique performs local birefringence measurements by measuring the evolution of the states of polarization (SOP). The birefringence information from such measurements was extracted and analysed to characterise four different fibres. Beat lengths and correlation lengths extracted from the P-OTDR were used to calculate the differential group delay (DGD) of the fibres. Next an expression for the root-mean-square differential group delay was derived and applied to the birefringence measurements to calculate the DGDs at a single wavelength. This method which operates at a single wavelength has a huge advantage. Firstly it is able to measure completely all the fibre characteristic parameters. Secondly it can measure mean DGD, root mean square DGD and instantaneous DGD. A plot of instantaneous DGD vs. length enables one to identify and eliminate sections with particularly high DGD. Finally since the P-OTDR system operates with a single wavelength, real time monitoring of PMD is possible via multiplexing. The results obtained are repeatable, accurate and are in good agreement with the standard Jones Matrix Eigenanalysis (JME) technique.
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  • Date Issued: 2013

The influence of inbound and outbound logistics on the competitiveness of the South African automobile industry

  • Authors: Fourie, Quinton
  • Date: 2013
  • Subjects: Business logistics -- South Africa -- Costs , Competition -- South Africa , Automobile industry and trade -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8863 , http://hdl.handle.net/10948/d1020217
  • Description: The South African automotive industry has been identified as an important influence on the economy of South Africa. In particular, it plays a role in job creation in a country with high unemployment rates. However, being linked to a global industry, its competitive position and future relevance have come into question on numerous occasions. After a period of isolation and protection, the local industry had to enter global competition. The competitive playing field had suddenly widened from companies competing locally amongst each other for local market share, to competing globally for international sales. In addition it was found that competition was not only limited to opposing brands but also existed within the subsidiaries of the same brand. The reason for this was the existence of overcapacity in the manufacturing facilities internationally. Coupled with this, most of the dominant vehicle manufacturers were creating more capacity in developing markets to support demand as well as to benefit from cheaper resources. There are of course many influencing factors on the competitive position of such an important industry. The value chain has been identified as a tool to analyse and compare the activities within rival businesses or industry role players. Two primary activities within the value chain are inbound logistics and outbound logistics. The objective of the research was to investigate the influence of inbound and outbound logistics on the competitiveness of the South African automotive industry. A literature review created the conceptual framework for the research. It was necessary to discuss the automotive industry in a global sense to understand the history and trends of the development within the industry. It was also necessary to understand the South African automotive industry within this context to identify its place and relevance in global terms. It was found that, although important to the local economy, the local industry was not a dominant force to be reckoned with and was in fact being over taken by many of its competitors. Part of this investigation was spent on the development of the local industry in a protected environment and what it meant for the growth of local content and exports. This was also important as the component manufacturers based in South Africa need critical mass to create an efficient platform to be globally competitive. It was found that historic development programmes did not do much to improve this aspect but there is optimism about the latest programme which promotes an increase in production volumes. The state of logistics in South Africa was critically analysed to understand the influence it has on the automotive industry. It was found that although the logistics infrastructure within South Africa is the best in Africa, it is behind the standards of its competitors. This is influencing the automotive industry as a result of inadequate rail infrastructure. The reason for this was that most of the freight which was being transported by road would be more efficiently transported by rail. The cost of logistics was also found to be high in South Africa and skills were also a concern to improve the current situation. A research questionnaire was created from the findings of the literature review. The questionnaire formed the primary research tool for this study. The sample was identified as respondents from vehicle assemblers and component manufacturers who would have sufficient knowledge of this topic. It was found that inbound and outbound logistics costs formed a relatively large component of total costs. The high levels of imported parts being used as well as export levels added to the logistics costs. This also caused uneconomical inventory levels as stock needed to be kept for longer periods before being replenished. The respondents were also aware of the fact that rail would improve the situation if the infrastructure was sufficient. The respondents seemed to be of the opinion that the skills of the employees responsible for logistics were not a major influencing factor and that logistics service providers were in addition, not creating an overwhelming cost improvement. The incentive programmes were also not seen to be doing much to address the influence of logistics on the automotive industry.
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  • Date Issued: 2013

The restoration of an alien-invaded riparian zone in grassy fynbos, South Africa

  • Authors: Fourie, Saskia
  • Date: 2013
  • Subjects: Fynbos ecology -- South Africa Riparian ecology -- South Africa Riparian restoration -- South Africa Alien plants -- South Africa Invasive plants -- South Africa Endemic plants -- South Africa Plants -- Effect of fires on -- South Africa Soil seed banks -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4733 , http://hdl.handle.net/10962/d1003840
  • Description: The most recent surveys in South Africa estimate that invasions are still increasing, despite substantial clearing efforts. Riparian systems in South Africa are particularly vulnerable to invasion by woody IAPs. This thesis addresses the restoration of alien‐invaded riparian systems, by investigating the factors that facilitate or constrain spontaneous recovery and influence the trajectories of succession. These factors include invasion history and management history, especially the use of fire. A seedling emergence approach was used to test the presence of a viable pre‐fire seedbank, and the effect of fire on the seed bank. The efficacy of some active restoration interventions was also tested, with the aim to return invasion‐resistant, indigenous vegetation with a structure and function representative of uninvaded sites. The findings of this study indicated the presence of a viable and persistent riparian soil seed bank, even after 30 years of intermtittent invasion as well as two fire cycles under invasion. It shows that the management practice of fell‐and‐burn resulted in high soil temperatures, and that this reduced the indigenous soil seed bank density, especially in the upper soil layer. Clear germination sequences and patterns of emergence over time for different species were observed during this study, with many species exhibiting delayed emergence relative to the timing of the fire event. It is proposed that manipulation of the season of fire could be used to selectively optimise the order of arrival and therefore superior recruitment of some species over others in the Eastern Cape fynbos, and thus alter the trajectories of recovery of vegetation towards a more desired state. Active restoration in the form of indigenous seed and plant additions resulted in a significantly higher indigenous cover after seven months, compared to a control (passive restoration) or restoring with grass. Indigenous cover and composition was also strongly influenced by lateral zonation, and some key guilds and species were missing or present in much lower densities compared to reference sites. Grass restoration significantly suppressed the regeneration of A. longifolia, as well as the regeneration of indigenous species. Biotic resistance can thus be achieved through restoration, and it could be a powerful tool in the management of IAPs, although the deliberate introduction of grass after clearing in fynbos also reduces biodiversity and could have unforeseen consequences to riparian function.
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  • Date Issued: 2013

Extreme weather events in the Sneeuberg, Karoo, South Africa: a case study of the floods of 9 and 12 February 2011

  • Authors: Fox, Roddy C , Rowntree, Kate M
  • Date: 2013
  • Language: English
  • Type: Article
  • Identifier: vital:6672 , http://hdl.handle.net/10962/d1004468
  • Description: Two destructive flood events occurred in rapid succession in the semi-arid Sneeuberg Mountains of the Karoo, South Africa in February 2011. The temporal and spatial characteristics of these two extreme events are examined in this paper through analysis of data from an unusually dense, and reliable, network of farm rain gauges. These analyses add to our understanding derived from existing rain gauge information. Comparisons are then made with patterns from a range of modeled products derived from remote sensed information: the Modern-Era Retrospective Analysis for Research and Applications (MERRA), the Tropical Rainfall Measuring Mission (TRMM) and the Global Land Data Assimilation System (GLDAS). We found that the first flood event was widespread and precipitation was related strongly to altitude. The second was highly localised, with no relationship to altitude. Both had very sharply peaked rainfall intensities. These findings are of significance to the studies of flooding and landscape change in the area as such events have become more pronounced over the past 50 yr and it is likely that this trend will accelerate. The modeled patterns are derived largely from remote sensing and we found that they are reliable for drawing out monthly and annual variations but they make noticeable underestimates. They are poor estimates, however, both for the spatial distribution of precipitation, and the short term trends as they struggle to estimate the impact of topography and other local forcing factors. This finding corroborates information derived from other analyses at broader spatial scales using more widely spread, established rain gauge stations. Ten percent of southern Africa has been classified as mountainous and these areas provide much of our water resources so our findings are significant to water managers throughout this and similar mountainous regions.
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  • Date Issued: 2013

The viability of introducing radio frequency identification to the South African truck tyre market: a cross-sectional study

  • Authors: Francis, Merwin
  • Date: 2013
  • Subjects: Business logistics -- South Africa Radio frequency identification systems , Inventory control -- South Africa Product life cycle
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/21678 , vital:29732
  • Description: Radio Frequency Identification (RFID) is revolutionizing business practices across industries worldwide as means for its commercial application continue to be developed. It is surpassing barcoding as the preferred means of product identification due to its’ ability to identify goods at item-level as opposed to batch- or type identification, and with no line-of-sight requirements for item detection. Although many industries have successfully employed the technology and are reaping the rewards, RFID’s adoption in the truck tyre industry is still in its infant stage. A small number of documented cases discuss the limited roll-out and testing of RFID effectiveness in satisfying the demands and expectations associated with this specific application. This study is aimed at evaluating the viability of introducing RFID to the South African market. The market readiness is reflected in the perceptions of Continental Tyre South Africa’s (CTSA’s) customers regarding the perceived benefits of RFID. More importantly, it is revealed in how it affects customers’ buying behaviour and, by implication, the impact on CTSA’s sales. The results of the study also reveal critical aspects unique to the South African truck tyre market which could potentially be addressed through the introduction of RFID. These aspects form the basis of the conclusions and recommendations for future actions by CTSA.
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  • Date Issued: 2013

Investigating the prevailing knowledge about co-operatives in South Africa and the determinants of their success

  • Authors: Frans, Nonyameko
  • Date: 2013
  • Subjects: Cooperative societies -- South Africa , Cooperative societies -- Management
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8862 , http://hdl.handle.net/10948/d1020206
  • Description: The development of co-operatives has been increasingly seen, both globally and in developing countries, as a key strategy for a high economic growth rate, job creation and poverty alleviation. In trying to address these challenges, the South African government has been promoting co-operatives as an instrument for economic growth and socio-economic integration. Despite the realisation of the important role that cooperatives could play, not enough research has been done on the successes and failures of these organisations in achieving economic growth and socio-economic development in countries. The present study is an attempt to address this research gap. The primary objective of this study was to increase the success of co-operatives in South Africa by investigating the prevailing nature of operations of co-operatives and the determinants of the success of these organisations. More specifically, the study gathered qualitative information about co-operatives, identified which factors influence co-operatives in general and investigated which of these factors are the most important determinants of the success of these organisations in South Africa. A census was conducted of the 110 co-operatives registered in the database of the Leadership Academy (LA) of the NMMU Business School. Only 50 executive members of 26 co-operatives participated in the study (response rate of 23.6 percent). The empirical results revealed that the two most critical success factors for co-op success were the handling of finances and leadership; that language groups viewed coop success differently; and that females provide stronger leadership than males in cooperatives. The results also showed that skills development is an important factor in achieving these critical success factors. These results presented important managerial implications for the success of co-operatives.
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  • Date Issued: 2013

A framework to mitigate phishing threats

  • Authors: Frauenstein, Edwin Donald
  • Date: 2013
  • Subjects: Computer networks -- Security measures , Mobile computing -- Security measures , Online social networks -- Security measures
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9832 , http://hdl.handle.net/10948/d1021208
  • Description: We live today in the information age with users being able to access and share information freely by using both personal computers and their handheld devices. This, in turn, has been made possible by the Internet. However, this poses security risks as attempts are made to use this same environment in order to compromise the confidentiality, integrity and availability of information. Accordingly, there is an urgent need for users and organisations to protect their information resources from agents posing a security threat. Organisations typically spend large amounts of money as well as dedicating resources to improve their technological defences against general security threats. However, the agents posing these threats are adopting social engineering techniques in order to bypass the technical measures which organisations are putting in place. These social engineering techniques are often effective because they target human behaviour, something which the majority of researchers believe is a far easier alternative than hacking information systems. As such, phishing effectively makes use of a combination of social engineering techniques which involve crafty technical emails and website designs which gain the trust of their victims. Within an organisational context, there are a number of areas which phishers exploit. These areas include human factors, organisational aspects and technological controls. Ironically, these same areas serve simultaneously as security measures against phishing attacks. However, each of these three areas mentioned above are characterised by gaps which arise as a result of human involvement. As a result, the current approach to mitigating phishing threats comprises a single-layer defence model only. However, this study proposes a holistic model which integrates each of these three areas by strengthening the human element in each of these areas by means of a security awareness, training and education programme.
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  • Date Issued: 2013
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