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Development of conservation strategies for Alepidea Amatymbica ECKL. & ZEYH. : a rare medicinal plant in the Eastern Cape, South Africa

  • Authors: Mangoale, Ramatsobane Maureen
  • Date: 2017
  • Subjects: Medicinal plants Plants, Cultivated
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10353/8667 , vital:33400
  • Description: Conservation through cultivation has been recommended as a means to relieve overexploitation of medicinal plants. However, the medicinal plants users believe that plants collected from the wild are more potent than cultivated ones. Hence, there is a need for scientific documentation of the potency of cultivated medicinal plants to contribute to the development of a sustainable management strategy to conserve wild populations. This study was aimed at documenting cultivation techniques of a known medicinal plant, Alepidea amatymbica and to validate its medicinal efficacy. In order to identify overexploited medicinal plants in the study area and thus develop their conservation strategy, a survey on the trade of medicinal plants was conducted in selected towns of Amathole District Municipality of the Eastern Cape, South Africa. The survey revealed 67 plants belonging to 46 different families. Twenty-five medicinal plants were identified as overexploited and scarce and they were prioritized for conservation. Furthermore, 69.14 percent of the respondents were not willing to use cultivated medicinal plants. Lack of belief on the potency of cultivated plants and cultivation techniques were mentioned as the most significant constraints to conservation of medicinal plants. Also, the time for cultivated plants to reach maturity deterred herbal medicine practitioners from cultivating them. Alepidea amatymbica was mentioned as one of the most overexploited medicinal plants which has become scarce in the study area. This medicinal plant was therefore selected for this study. In order to develop sustainable conservation program for the species, various studies which include survey on the medicinal plants trade, cultivation, comparative micromorphology, elemental composition, toxicity, phytochemical and antioxidant activity of the wild and cultivated A. amatymbica were conducted. Cultivation of Alepidea amatymbica was conducted to determine the appropriate planting depth and rhizome fragment length for the growth of this plant. The experiment was laid out in a Complete Randomized Block Design (CRBD) with two factors in 6×3 factorial design. There were six levels of fragment length (1, 2, 3, 4, 5 and 6 cm) and three levels of burial depth (2.5, 5 and 7.5 cm). Emergence rate, number of leaves, leaf area, and plant height, number of florets, rhizome length gain, rhizome weight gain, shoot moisture and rhizome moisture were measured as growth parameters. The best overall yield in terms of plant height, shoot emergence, rhizome weight gain, number of florets and number of leaves was observed in 7.5 cm planting depth at 6 cm rhizome length. Four centimetre rhizome length had the highest leaf area of 111.9±3.5 cm2, 101.3±3.5 cm2, 105±3.5 cm2 at 2.5, 5, 7.5 cm planting depth respectively. Shorter fragment lengths showed high potential for vegetative propagation in terms of rhizome length gain at all burial depths. Scanning electron microscopy (SEM) was used to examine the foliar micro morphological characteristics while energy dispersive x-ray spectroscopy (EDXS) was used to determine the elemental composition in different parts of the wild and cultivated plants. The study revealed numerous differences between the wild and cultivated ones. These include deposition of epicuticular waxes, stomatal apparatus, helical thickening of the xylem walls, thickening of the epidermal cell layer and presence of starch grains in the parenchyma cells of the cortex. The EDXS analysis also revealed disproportionate quantities of C, O, Ca, K, Al, Mg, Si, Br and N as the major constituents in both cultivated and wild A. amatymbica specimens. The quantities of elements varied in the different parts of wild and cultivated plants. Toxicity of the methanol, water and acetone extracts of the fresh rhizome of the wild and cultivated A. amatymbica were evaluated using hatchability of cysts and lethality on the hatched cysts (nauplii) of Artemia salina. The highest hatching success was observed in the water extracts of the wild plant (46.16percent) with a MIC of 0.184 mg/ml while the cultivated plants had a hatching success of 40.83percent with MIC of 0.208 mg/ml. Highest mortality was observed in the acetone extract of the wild plants at the lethal dose of 0.191 mg/ml while the cultivated plant had a lethal dose of 0.270 mg/ml. Water extracts of both wild and cultivated plants showed similar lethal dose (LD50) of >1 mg/ml. Methanol extracts of both the wild and cultivated species exhibited almost the same level of toxicity (0.695 mg/ml and 0.628 mg/ml, respectively). Based on the Bastos criterion of toxicity indices of the lethality test, all the plant fractions demonstrated cytotoxicity effect, although the degree of their toxicity varied among the plants used. Standard spectrophotometry assays were used to quantify the phytochemical contents and to determine the antioxidant potentials of the cultivated and wild A. amatymbica. The results revealed different levels of phytochemicals with corresponding antioxidant activities. The wild extracts had higher phytochemical contents in most of the assays than cultivated extracts. Total phenol in the wild extracts ranged from 32.30±3.43 to 117.8±8.45 mg GAE/g with the acetone extracts having the highest content while the water extracts was the least. The range in the total phenol of the cultivated species was 66.46±5.29 to 98.44±6.08 mg GAE/g with the methanol extracts having the highest content while water extracts was the least. The flavonoids content ranged from 55.01±6.51 to 99.09±7.20 mg QE/mg and from 48.65±7.74 to 67.32±4.1 mg QE/mg for the wild and cultivated plants, respectively. The alkaloids contents ranged from 14.70±0.04 to 17.80±0.015 percent in the wild species while it ranged from 11.98±0.14 to 13.21±0.06 percent in the cultivated species. The wild species also showed higher antioxidant activities in most of the assays evaluated. The study revealed successful cultivation of the wild species of Alepidea amatymbica using fragments from the rhizome. The micromorphological study of both the wild and cultivated species showed minimal differences in the helical thickening of the walls in the xylem vessels and starch grain accumulation pattern. Although herbal medicine practitioners believe that cultivated species are not potent, however this study revealed some levels of phytochemicals contents and antioxidant activities which are comparable to the wild species. Cultivation is a major strategy in conserving nature and their resources. Hence, the successful domestication of A. amatymbica would help in reducing the pressure on the wild species while also meeting their medicinal demands purposes, utilisation and conserving for future generations.
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  • Date Issued: 2017

Developmental dynamics in land reform projects : comparative studies of two different land reform projects, farm-worker equity schemes and beneficiary-owned and run citrus projects

  • Authors: Tiwana, Sebenzile Wilbert
  • Date: 2017
  • Subjects: Land reform -- South Africa -- Eastern Cape Sustainable development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSoc
  • Identifier: http://hdl.handle.net/10353/5047 , vital:29025
  • Description: In this study, a comparison was made between two different land reform models in the Sarah Baartman District of the Eastern Cape to, firstly; evaluate and identify factors that influence long-term sustainability and prosperity of farms owned and run by beneficiaries, and farms jointly owned by beneficiaries and former farmer / mentor in a share equity scheme, referred to as Farmworkers Equity Share Schemes (FWES), and secondly; to identify forms of government support in each of the two models. Mixed methods were used to collect data for the study. It involved the administration of structured interviews to beneficiaries, and semi-structured interviews with the mentor and government officials. The study found that the equity share scheme improved the livelihood of the beneficiaries in terms of getting annual dividends and acquiring new properties, empowered beneficiaries in decision-making in terms of having a say in financial expenditure on farm operations and the structuring of dividend pay-outs, and the project showed great potential of long-term sustainability and prosperity. Conversely, the beneficiary-owned and run project did not improve the lives of beneficiaries, was prone to infighting and fraught with organisational and management problems with no prospects of long-term sustainability and economic viability.
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  • Date Issued: 2017

Devulcanization of model compounds by a variety of diphenyldisulfides

  • Authors: Boyce, Annemè
  • Date: 2017
  • Subjects: Rubber -- Recycling Rubber, Reclaimed , Rubber -- Standards -- South Africa Rubber -- Research Chromatographic analysis
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/14730 , vital:27834
  • Description: Improvements to the properties of recycled rubber, by developing a more selective breakdown process, is an important issue and a global challenge. Devulcanization is the most promising way to achieve this. It is a process which aims to totally or partially cleave monosulfidic (C-S-C), disulfidic (C-S-S-C) and polysulfidic (C-Sx-C) crosslinks of vulcanized rubber. In this study, the devulcanization of sulfur-vulcanized natural rubber with a variety of diphenyldisulfides has been studied using 2,3-dimethyl-2-butene and squalene as model compounds, vulcanized by sulfur and 2-bisbenzothiazole-2,2’-disulfide. 2-aminodiphenyldisulfide; 4-amino-diphenyldisulfide; bis(2-benzamido-)diphenyldisulfide and 2,2’-bithiosalicylic acid were used as aromatic disulfides devulcanization agents. Thermal analysis was used to investigate interactions between various combinations of curatives in the vulcanization systems in the absence of model compounds. Thermogravimetric analysis was used to detect mass changes during vulcanization and whether the samples decompose/evaporate so as not to contaminate differential scanning calorimetry instrumentation. Differential scanning calorimetry was used to investigate reactions occurring between curatives. Comparison of reversing and non-reversing signals in modulated experiments are suggestive of reactions between devulcanization agents and sulfur, and accelerators Vulcanization of the model compounds were performed in 10m evacuated sealed glass ampoules placed in an oil bath at 160 °C and agitated for the duration of vulcanization. After 60 min the ampoules were removed and quenched. These were then devulcanized by exposure to a devulcanization agent in a sealed ampoule at 180 for 60 min. Crosslinked 2,3-dimethyl-2-butene species were isolated and analysed by reversed phase high performance liquid chromatography. Particular attention was paid to changes in the number of sulfur atoms in the crosslinks. Results indicate that of the devulcanization agents tested 4-amino-diphenyldisulfide was the most effective. No detrimental effect on devulcanization efficiency was caused by the substitution of a basic amino group with an acidic carboxylic acid group Gel permeation chromatography was performed on devulcanized squalene crosslinks using a tetrahydrofuran eluent. GPC investigations with squalene were less effective than HPLC experiments with 2,3-dimethyl-2-butene at evaluating the relative efficiency of individual devulcanization agents. Results were, however, consistent with 4-amino-diphenyldisulfide again being the most efficient devulcanization agent.
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  • Date Issued: 2017

Diamond turning of contact lens polymers

  • Authors: Liman, Muhammad Mukhtar
  • Date: 2017
  • Subjects: Diamond turning Contact lenses , Electrostatic lenses Lenses -- Design and construction Neural networks (Computer science)
  • Language: English
  • Type: Thesis , Masters , MEng
  • Identifier: http://hdl.handle.net/10948/19223 , vital:28789
  • Description: Contact lens production requires high accuracy and good surface integrity. Surface roughness is generally used to measure the index quality of a turning process. It has been an important response because it has direct influence toward the part performance and the production cost. Hence, choosing optimal cutting parameters will not only improve the quality measure but also the productivity. In this study, an ONSI-56 (Onsifocon A) contact lens buttons were used to investigate the triboelectric phenomena and the effects of turning parameters on surface finish of the lens materials. ONSI-56 specimens are machined by Precitech Nanoform Ultra-grind 250 precision machine and the roughness values of the diamond turned surfaces are measured by Taylor Hopson PGI Profilometer. Electrostatics values were measured using electrostatic voltmeter. An artificial neural network (ANN) and response surface (RS) model were developed to predict surface roughness and electrostatic discharge (ESD) on the turned ONSI-56. In the development of predictive models, turning parameters of cutting speed, feed rate and depth of cut were considered as model variables. The required data for predictive models were obtained by conducting a series of turning test and measuring the surface roughness and ESD data. Good agreement is observed between the predictive models results and the experimental measurements. The ANN and RSM models for ONSI-56 are compared with each other using mean absolute percentage error (MAPE) for accuracy and computational cost.
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  • Date Issued: 2017

Die kriteria vir ’n tweerigtingaanleerderwoordeboek met Afrikaans en Frans as taalpaar

  • Authors: Stone, Hanel , Vrancken, Maria
  • Date: 2017
  • Subjects: Afrikaans language -- Lexicography , Afrikaans language -- Lexicology , Lexicography
  • Language: Afrikaans
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/13789 , vital:27308
  • Description: Die gevarieerde landskap van leksikografie stel aanleerders uit verskillende sosiale agtergronde in staat om ’n vreemde taal vanuit hul eie moedertaal aan te leer. Gevolglik is een van die maniere waarop taalverwerwing bevorder kan word, veral deur die ontwikkeling van aanleerderwoordeboeke, meer spesifiek vreemdetaalwoordeboeke wat volwassenes bemagtig om die vreemde taal aan te leer om beide resepsie en produksie van die taal te bemeester. Die ontwerp en samestelling van ’n woordeboek is ’n komplekse saak, want onder andere moet die verskille tussen kultuurgroepe, die vlak van die aanleerder se vermoë om ’n taal aan te leer, die aanleerder se kennis van die betrokke taal en die beskikbaarheid van leermateriaal en bronne in ag geneem word. Hierby moet ook vertaalekwivalente in beide tale vir resepsie en produksie verskaf word. Die doelwit van hierdie studie is om ’n raamwerk daar te stel vir die kriteria van ’n tweerigtingaanleerderwoordeboek met Afrikaans en Frans as taalpaar. Die hipotese is dat dit moontlik is om ’n doeltreffende raamwerk vir die kriteria vir ‘n tweerigting-aanleerderwoordeboek met Afrikaans en Frans as taalpaar te ontwikkel. Die motivering vir hierdie studie is deels gegrond op die gebrek aan aanleerderwoordeboeke met Afrikaans en Frans as taalpaar. Die Afrikaanssprekende moet tans Frans deur middel van Engels aanleer vanweë die gebrek aan leermateriaal. Die navorser se persoonlike ervaring met die aanleer van Frans as vreemde taal het die ondersoek verder geïnspireer. Kriteria vir ’n tweerigtingaanleerderwoordeboek met Afrikaans en Frans as taalpaar is vasgestel aan die hand van ’n literatuuroorsig. Die geïdentifiseerde kriteria is in detail bespreek en aan die hand van praktiese voorbeelde eksemplaries toegelig.
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  • Date Issued: 2017

Dietary diversity amongst adults who buy at shopping malls in the Nelson Mandela Bay area

  • Authors: De Bruin, Eunice Mari
  • Date: 2017
  • Subjects: Nutrition -- South Africa -- Port Elizabeth , Older people -- Nutrition Diet Food security -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/15027 , vital:28114
  • Description: Background: Assessing the level of dietary diversity and contributing factors that influence the level of dietary diversity amongst adults can highlight gaps in nutrition interventions, policies and programmes, which aim at combating the double burden of malnutrition. Aim: The aim of this study was to determine which factors and relationships affect the level of dietary diversity of adults in the Nelson Mandela Bay area. Design: An exploratory comparative, cross-sectional, quantitative study design with a qualitative component that was utilised. Both interviewer- and participantadministered questionnaire sections were applied. Data were analysed using IBM SPSS Statistics, Statistica Version 12, Microsoft Office Excel 2007, Spearman rho correlation co-efficient and Pearson’s chi-square test (p-value <0.05). Participants and setting: A convenience-stratified sample (n=480) was used, consisting of adults who reside and shop at shopping centres in the Nelson Mandela area, after obtaining informed consent. Results: The findings indicated that adults in the Nelson Mandela Bay area who shopped at shopping malls had a medium level of dietary diversity. The dietary patterns found were not in line with the South African Food Based Dietary Guidelines. The most consumed food items were ‘cereals' (95%), 'sweetening agents and sweets' (89%) and ‘spices, condiments and beverages’ (87%). Fruit (45,2%) and vegetables (64,8%) were generally poorly consumed. Significance was shown as having an effect on the level of dietary diversity for factors such as ethnicity, level of education, amount of money spent on food purchase per month, distance travelled to purchase food, and nutrition knowledge. Conclusion: The study suggests that adults living in the Nelson Mandela Bay area have a medium level of dietary diversity, with practices that are not in line with the recommended South African Food Based Dietary Guidelines. Strategies, including nutrition education promotion and the implementation of current policies, programmes and interventions, should be implemented and/or strengthened to encourage behaviour change.
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  • Date Issued: 2017

Dietary tracers and stomach contents reveal pronounced alimentary flexibility in the freshwater mullet (Myxus capensis, Mugilidae) concomitant with ontogenetic shifts in habitat use and seasonal food availability

  • Authors: Carassou, Laure , Whitfield, Alan K , Moyo, Sydney , Richoux, Nicole B
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/456201 , vital:75493 , xlink:href="https://doi.org/10.1007/s10750-017-3230-3"
  • Description: We investigated ontogenetic and seasonal variations in the diet of the freshwater mullet (Myxus capensis) across a river–estuary interface using dietary tracer (stable isotopes and fatty acids) and stomach content analyses. Two hypotheses were tested: (A) the freshwater mullet diet shifts as individuals grow and migrate from the estuary to the river, and (B) the dominant food resources utilized by freshwater mullet vary through time, mainly as a function of the seasonal changes in the availability of preferred food items in each habitat. Both hypotheses were supported, as our results indicated broad dietary flexibility by M. capensis, with utilized food items ranging from benthic microalgae to insects depending on habitat and seasonal patterns in availability of resources. Given the unexpected importance of invertebrate-derived prey, including some of terrestrial origin (i.e. aerial or semi-aquatic insects), during the freshwater phase of the M. capensis life cycle, we also emphasize a need for a re-assessment of the trophic designation of this species (previously designated as a strict detritivore).
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  • Date Issued: 2017

Differential regulation of wheat (Triticum aestivum) callose synthases during Russian wheat aphid (diuraphis noxia)infestation

  • Authors: Ngwenya, Nompilo
  • Date: 2017
  • Subjects: Russian wheat aphid Wheat -- Diseases and pests
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/8100 , vital:31522
  • Description: Plant production serves as the primary food source for all living beings and is continuously being affected by many biotic and abiotic factors. Wheat, one of the most consumed cereal crops in the world and the second most cultivated crop after maize in South Africa, is continuously being affected by Russian wheat aphid (RWA) since 1978. To counteract the effect of this aphid, the first resistant wheat cultivar was developed in 1984 in South Africa containing the Dn1 resistance gene. However, the mechanism of action of the resistance is still not fully understood to date. The feeding of the RWA on the wheat induces callose deposition especially in susceptible wheat cultivars, linking the β-1.3-polysaccharide (callose) to the resistance mechanism. Callose is synthesized by callose synthases, also known as glucan synthase-like genes (GSL). Not much is known about the mechanism of action of callose synthases or how they are regulated in response to the RWA. Bioinformatics tools, such as those available at NCBI, were used to identify the wheat callose synthases genes. The proteins encoded by the identified wheat callose synthases genes, were then analyzed for conserved domain motifs using the MEME suite and InterproScan, sequence similarities using ClustaL Omega and transmembrane domains using HMMTOP and ProtCamp. These were then compared with those of the already characterized Arabidopsis callose synthase proteins in an attempt to identify the wheat callose synthase(s) that responds to aphid feeding. Further bioinformatics studies were carried out to identify the presence of biotic stress associated cis-acting regulatory elements found in the 1.5 kbp upstream region of the start codon of the Arabidopsis callose synthase genes. Eight partial wheat callose synthase sequences were identified and two of these (TaGSL2 and TaGSL22) showed high similarities to the AtGSL5, which is up-regulated in response to aphid feeding in Arabidopsis. Six of the wheat callose synthase genes were mediated to code for the functional callose synthases proteins: TaGSL3, 8, 12, 19, 22 and 23, and analyzed for conserved protein motifs. Based on the sequence similarities and conserved protein domains, TaGSL2 and TaGSL22 were found to be the most similar to AtGSL5 and most likely to respond to RWA infestation. Cis-acting regulatory element analyses confirmed the possibility of TaGSL22 being responsible for callose deposition in wheat as biotic stress associated cis-acting regulatory elements, Box W1, TC- rich element and W- box were all found in the 1.5 kbp upstream of the TaGSL22 coding region. Callose was quantified in both susceptible and resistant wheat cultivars using the aniline blue fluorescence method. When infested with RWA-SA1, the susceptible wheat cultivar (Tugela) deposited significantly higher amounts of callose, compared to the resistant wheat cultivar (Tugela DN), which deposited little, to no callose with respect to the control samples. Transcription analysis, of the TaGSL2 and TaGSL22 in RWA-SA2 infested Tugela and Tugela DN wheat cultivars, was performed using real time polymerase chain reaction (qPCR). Both TaGSL2 and TaGSL22 genes were up-regulated in Tugela and Tugela DN wheat cultivars in response to RWA-SA2 infestation, with TaGSL22 being more expressed than TaGSL2 in both cultivars, indicating that RWA-SA2 is able to overcome the resistance of Tugela DN and cause callose deposition. However, significantly higher expression of both genes was still observed in the susceptible, Tugela wheat cultivar. This study therefore confirms that callose deposition is associated with RWA-SA1 feeding, only in the susceptible wheat cultivar, Tugela and not the resistant cultivar, Tugela DN. However, during RWA-SA2 feeding, two of the eight identified callose synthases in wheat, are up-regulated in response to RWA-SA2 feeding, in both the resistant and susceptible wheat cultivars with higher levels observed in the susceptible wheat cultivar when compared to the resistant wheat cultivar. TaGSL2 and TaGSL22 are therefore implicated in the callose deposition observed in the susceptible and resistant wheat cultivars, after RWA-SA2 infestation. Further studies are required to confirm the differential regulation of the two wheat callose synthases proteins during RWA infestation and their possible role in the resistance mechanism of the resistant wheat cultivar, Tugela DN.
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  • Date Issued: 2017

Differentiating engagement of opportunity identification: a grounded theory study of Chinese immigrant entreprenuers

  • Authors: Ndoro, Tinashe Tsungai Raphael
  • Date: 2017
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/5568 , vital:20942
  • Description: The aim of this study was to develop a substantive grounded theory describing how Chinese immigrant entrepreneurs who own and operate small retail businesses in the Eastern Cape province of South Africa identify opportunities in the business environment. The substantive grounded theory was developed using the prescripts of grounded theory proposed by Strauss and Corbin (1990). In this respect, a substantive grounded theory called differentiating engagement of opportunity identification was developed from a sample of 41 qualitative interviews conducted with Chinese immigrant entrepreneurs. The study found that Chinese immigrant entrepreneurs identified various opportunities (startup, sales, operational, relational) in the business environment through their dynamic interactions and relationships with different stakeholders. These stakeholders mainly included family members, local employees and customers. The Chinese immigrant entrepreneurs displayed two interactional processes in their interactions with stakeholders, namely engaging in and disengaging from interactions. These interactional processes enabled the Chinese immigrant entrepreneurs to identify opportunities and operate their small businesses in the business environment. Assumptions held about the interactions and relationships with stakeholders in the host community were central to the interactional processes displayed by the Chinese immigrant entrepreneurs. As they operated their small businesses, the Chinese immigrant entrepreneurs would engage in interactions with customers who were perceived as favourable (approachable). From these interactions with favourable (approachable) customers, the Chinese immigrant entrepreneurs were able to identify opportunities (gaining customer insight of opportunity), whereas they would disengage from interactions with customers perceived as unfavourable (unapproachable). In this respect, they would delegate their local employees (actions of delegation in business) with the responsibility of interacting with unfavourable and hostile customers. Additionally, the Chinese immigrant entrepreneurs would engage in interactions with local employees to gain insight into local indigenous products and identify opportunities in the host community. In order to identify other opportunities (operational, relational), the Chinese immigrant entrepreneurs would disengage from interactions with local employees and engage in interactions with other stakeholders such as family members. The varying differentiated interactions and relationships established by the Chinese immigrant entrepreneurs with different stakeholders created a relational context which enabled the identification of opportunities in the host environment. Thus, the findings of the present study and the substantive grounded theory developed (differentiating engagement of opportunity identification) are discussed from the perspective of social capital, social exchange theory and Chinese cultural values. Finally, the theory developed in the present study contributes to the understanding of the processes of how social capital and relationships contribute to the process of identifying opportunities and operating a small business by immigrant entrepreneurs within a host environment.
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  • Date Issued: 2017

Differentiations and intersections: a corpus-assisted discourse study of gender representations in the British press before, during and after the London Olympics 2012

  • Authors: Jaworska, Sylvia , Hunt, Sally
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/139205 , vital:37714 , DOI 10.1558/genl.28858
  • Description: This study examines the impact of a global sports event on gender representations in media reporting. Whereas previous research on gender, sport and media has been mainly concerned with sports events in the North American or Australian context, this study investigates the British media reporting before, during and after the London Olympics 2012. Our study follows the approach of Corpus-Assisted Discourse Studies (CADS) and uses both quantitative and qualitative research procedures. The results reveal more balanced gender representations during the London Olympics in that the ‘regular’ biased associations were supressed in favour of positive references to female achievements. However, little carry-though of the ‘gains’ was noted. Also, this study shows that the positive associations intersected with national sentiments and were used to celebrate the nation-state. At the same time, some subtle resistance was observed to accepting as ‘truly’ British the non-white athletes and those not born in Britain.
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  • Date Issued: 2017

Dinoflagellate communities in Algoa Bay: abundance and dynamics

  • Authors: Van Zyl, Hendrik Francois
  • Date: 2017
  • Subjects: Marine microbiology , Microbiology Marine biology -- Indian Ocean
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/21218 , vital:29457
  • Description: The contribution of dinoflagellates to the phytoplankton of Algoa Bay is largely unknown. This study aimed to address this, but additionally considered seasonal and spatial variation in the dinoflagellate communities of Algoa Bay. Phytoplankton abundance and the inorganic nutrients ammonium, total oxidized nitrogen, soluble reactive phosphorus and silicate were analysed. Diatoms dominated the phytoplankton community in most samples, with dinoflagellates only occasionally dominating the community. No seasonality could be detected in dinoflagellate abundance. Furthermore, no significant spatial patterns could be distinguished in dinoflagellate abundance, with the only exception being that the Port Elizabeth harbour waters contained significantly fewer dinoflagellate cells than the younger Ngqura harbour. Total phytoplankton abundance was correlated with inorganic nitrogen concentrations, but this was due to diatoms – dinoflagellate abundance did not correlate significantly with any nutrient measured. Both the common, historically bloom-forming Noctiluca scintilans, as well as the recently red tide-forming Lingulodinium polyhedra were recorded during the study, the latter almost exclusively from the harbours, which can be considered repositories of these toxic and harmful algal cells. The findings suggest that dinoflagellates in Algoa Bay are a robust phytoplankton group able to survive, and often thrive, in wide range of environmental conditions.
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  • Date Issued: 2017

Direct income tax and the digital economy

  • Authors: Mackenzie, Lara
  • Date: 2017
  • Subjects: Income tax Corporations -- Taxation , information technology -- Economic aspects Electronic commerce
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10948/18047 , vital:28568
  • Description: Due to the nature of the digital economy, multi-national entities are able to trade in countries over the internet without a physical presence, they are setting up group structures across the world, housing intellectual property in tax havens and shifting profits between jurisdictions, lowering their group tax rates. This treatise considered the OECD/G20 BEPS Project 2015 Final Report on Action Plan 1 which discusses the nature, risks and proposed options to combat base erosion and profit sharing (BEPS). Although the OECD have made no recommendations in their report many countries have taken action to protect their tax bases. The scope of this treatise is limited to multi-national entities who avoid tax presence in a country or shift profits to off-shore entities in low/no tax jurisdictions. The aim of this treatise is to identify the risks posed by the nature of the digital economy to direct taxation and analyse proposed solutions to respond to these risks. A comparative study of the proposal and changes implemented in the UK, Australia and India was undertaken to gain an understanding of international thinking regarding the best way to combat BEPS. These proposals were then compared to the South African perspective in order to determine which of the proposals would be feasible to combat BEPS in South Africa.
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  • Date Issued: 2017

Disasters and development nexus : theory and practice - a case of Zimbabwe

  • Authors: Chatora, Gift
  • Date: 2017
  • Subjects: Disaster relief Human beings -- Effect of environment on Political ecology
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/11525 , vital:39080
  • Description: This study is premised on the notion that disasters and development have a nexus, both theoretically and practically although the two fields have been traditionally viewed as antagonistic at face value. The principal objective was to analyze the existing theoretical and practical gaps between disasters and development in Zimbabwe. Furthermore, factors that affect achievement of disaster mitigation and development linkages in Zimbabwe were critically examined. The study conceptualizes disasters and development from multiple angles. The nested relationship between disasters and development are reinforced with the use of multiple disaster risk reduction strategies to mitigate vulnerability in both rural and urban areas. Hence, this study opted for the mixed methods approach from conceptualization throughout the research process so as to capitalize on the strengths entrenched in both qualitative and quantitative approaches. Drawing on a mixed methodology approach, this study approached the variables from multiple dimensions since disasters and development are intertwined. Evidently, the study demonstrates that disasters and development have a strong nexus, theoretically and practically. This confirms the study hypothesis that disasters and development are correlated, as disasters can both destroy development initiatives and create development opportunities, and that development schemes can both increase and decrease vulnerability. The study also found that policy practice in Zimbabwe is heavily fragmented, thereby leading to incoherent policy implementation. This results in increased vulnerability and huge disaster impacts that erode development gains therefore compromising achievement of sustainable development goals. Hence, the study recommended for the adoption of a Disaster Risk Reduction theoretical framework in cementing the disasters and development linkages theoretically and pragmatically. DRR enhances community’s resilience capacity in curtailing the progression of vulnerability and mitigate the accelerated incubation of disasters that impact on development strides.
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  • Date Issued: 2017

Disclaiming/denigrating/dodging: white South African academics’ everyday racetalk

  • Authors: Vincent, Louise , Idahosa, Grace E , Msomi, Zuziwe
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141900 , vital:38014 , DOI: 10.1080/14725843.2017.1292119
  • Description: The call for the ‘transformation’ of higher education in South Africa is one instance of a wider effort, since the country’s first democratic election in 1994, to surmount an apartheid and colonial legacy of institutionalised racism. In 2015 and 2016 nationwide protests led to universities being shut down as students and staff expressed frustration institutions that continue to be experienced as racist and ‘untransformed’. In this study we report on interviews conducted with senior white academics at one South African university shortly before these protests began. Given that our participants are people of influence in their respective university departments, we asked, in in-depth open-ended interviews, what contribution they saw themselves making to ‘transformation’. We argue that the talk of these participants could be described as what authors in the field call 'racetalk', Talk is understood here as a form of social practice, the analysis of which helps us to understand how racism is reproduced in mundane ways which, taken together, account for the persistence of pervasive institutionalised racism in South African higher education that appears impervious to policy and regime change.
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  • Date Issued: 2017

Discovering the root of obesity through the symbology of food: a historical and cultural exploration

  • Authors: Jacobs, Nadine
  • Date: 2017
  • Subjects: Obesity -- Psychological aspects , Obesity -- Research Behavior modification Psychophysiology
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/17569 , vital:28379
  • Description: Obesity is fast becoming a worldwide issue with detrimental health consequences. The increasing availability of effective nutritional strategies, physical exercise regimes and behaviour modification approaches to weight loss do not offer a satisfactory explanation as to why only two to five percent of people who have lost weight successfully manage to retain the weight loss over the long term. By referring to several concepts on how the symbols of food originate in the unconscious and end up becoming the unconscious impetus for conscious thought and dietary behaviours relating to food, the complexity of food pathologies, with specific reference to obesity is explored. The study presents a narrative review of the available literature on symbols in a variety of cultural-historical contexts through the theoretical lens of the psychoanalytic framework. The study contributed to the current treatment approaches to obesity, by highlighting how the unconscious content of the psyche serve to compromise conscious efforts to address the problem of obesity. Also, the need for further research into the development of a model that, by incorporating the psychoanalytic approach to obesity, will support the long-term success of weight loss intervention by addressing the underlying issues, is emphasised.
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  • Date Issued: 2017

Discrimination based on age in labour law

  • Authors: Oosthuizen, Tania
  • Date: 2017
  • Subjects: Age and employment -- Law and legislation -- South Africa , Discrimination in employment -- Law and legislation -- South Africa , Age discrimination in employment -- Law and legislation -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10948/19484 , vital:28884
  • Description: This piece aims to prove that a compulsory retirement age can no longer be justified in South Africa as a constitutional state. In times where people are gradually reaching older ages due to advances in a variety of fields, it seemed that the concept of a compulsory retirement age requires an in depth consideration. This is especially measured against the backdrop of equality and discrimination legislation within The Republic of South Africa. The development of social security law provides the larger framework in which to understand the concept and intentions around retirement. Discrimination and equality legislation demonstrates that age as a listed ground for discrimination does not necessarily simplify the jurisprudence pertaining to it, especially where alternatives have been developed for continued employment. The main point of reference in the South African justice system concerning discrimination disputes is the Harksen v Lane test, whereas the principle encapsulated in Waco v Schweitzer, relates particularly to discrimination based on age. These judgements and subsequent application will be illustrated and considered during the course of this research. The influence of fund rules and fixed-term contracts on the situation will aim to show the reality of the situation. In an effort to show that the problem of an ageing workforce and retirement is not localised to South Africa, an international overview of other constitutional countries is included for context. The comparison goes further to include non-constitutional countries to illustrate the global issue. This comparison was also included in an effort to find alternative strategies that may be utilised in South Africa for retirement and age discrimination legislations and social policies.
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  • Date Issued: 2017

Discursive constructions of quality assurance: the case of the Zimbabwe Council for Higher Education

  • Authors: Chidindi, Joseph
  • Date: 2017
  • Subjects: Zimbabwe Council for Higher Education -- Evaluation , Education, Higher -- Zimbabwe , Universities and colleges -- Evaluation -- Zimbabwe
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/7800 , vital:21299
  • Description: Quality assurance is on the contemporary agenda in higher education and has been prioritised across the globe. It has been conspicuous through the emergence of numerous quality assurance bodies, and in Zimbabwe, where this study takes place, the government has constituted the Zimbabwe Council for Higher Education. This study aims to identify the discourses drawn on by academics and those working within Zimbabwe Council for Higher Education to construct the roles and processes of external quality assurance practices in universities in Zimbabwe. The study was grounded on the premise that external quality assurance processes in higher education can vary according to their contextual environment. Fairclough’s Critical Discourse Analysis as a method driven theory not only provided a methodology, a way of collecting and analysing my data, but it was also a substantive theory, which provided a particular way of understanding the world through discourse. Fairclough’s Critical Discourse Analysis is grounded in a Critical Realist view of the social world that enabled generalisations about the effect discourse was having on the phenomenon of interest: quality assurance in higher education. One-to-one and group interviews were used to yield exploratory, descriptive and explanatory data. To corroborate and augment data from interviews, key documents related to quality assurance in universities in Zimbabwe and obtained from the Zimbabwe Council for Higher Education were analysed. There were a number of profound discourses that emerged in the research study. There was a discourse of ‘control’ in which Zimbabwe Council for Higher Education put in place compliance mechanisms, setting minimum requirements for universities to offer ‘credible’ higher education. There was a discourse of ‘power struggle’ in which universities endeavoured to maintain their institutional autonomy in response to what was perceived as Zimbabwe Council for Higher Education’s requirement of compliance. In the context of higher education in Zimbabwe, an important implication of the study was evident in the discourse of ‘gold standard’ of quality assurance which assumed that quality entails a generic best practice but which fails to take context into account. While a generic ‘global’ notion of best practice in quality assurance was dominant in the discourses of quality identified in this study, there were other discourses that focused on what quality might look like within the resource constraints of the context. The study highlighted the importance of collegiality between quality assurance organisations and universities to realise success of quality assurance intentions.
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  • Date Issued: 2017

Dismissal for operational requirements in the context of collective bargaining

  • Authors: Mfaxa, Mncedisi
  • Date: 2017
  • Subjects: Collective bargaining -- South Africa , Collective bargaining -- Dismissal of Industrial relations -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10948/13923 , vital:27358
  • Description: The highly competitive environment in which companies functions prompts the need to review their operations which may include reconsideration of the manning levels, and or changing terms and conditions of employment in order to be able to survive and prosper economically. The difficulty arises when the employers have to respond to the challenges. By law the employers are legally prohibited from unilaterally effecting the changes to the terms and conditions of employment. Furthermore, changing terms and conditions of employment is dealt with through collective bargaining and as such, the dismissal is outlawed as a legitimate instrument to coerce the employees to concede to the proposals. So the employers have to obtain an agreement or consent with the affected employees. In terms of the 1956 LRA the employer could justifiably terminate the contract of employment within the context of collective bargaining. For the employer to avoid offending the lock out provisions in terms of the 1956 LRA, the lock-out dismissal had to be effected in order to achieve a specific purpose, and it had to be conditional. Unlike its predecessor, the 1995 Labour Relations Act introduced section 187(1)(c) which renders the so-called lock-out dismissal by an employer, within the context of collective bargaining, automatically unfair. Section 187(1)(c) categorises a dismissal as automatically unfair, if the reason is a refusal by employees to accept a demand in respect of any matter of mutual interest between them and their employer. The employers are however permitted in terms of the 1995 LRA, to dismiss the employees based on operational grounds, as long as the requisite process has been adhered to. The employers need to restructure their operations in order to ensure that terms and conditions of employment are responsive to operational needs. Where the employees’ terms and conditions of employment are not in line with the company operational requirements, the need to terminate the employment contracts of the employees may arise. The employers are within their right to terminate the service of the employees who refuse to accept changes to their conditions of service based on the employers’ operational requirements. The court in Schoeman v Samsung Electronics confirmed that employer’s right to run its business in a successful manner, which includes affecting changes to the existing terms and conditions of employment to be aligned with the market demand. The dismissal is outlawed as a mechanism to coerce the employees to acceptance the employer’s demand relating to matters of mutual interest. At the same time, the employers are within their rights terminate the service of the employees who refuse to accept changes to their conditions of service based on the employers operational requirements. There is a clear tension between sections 187(1) (c), 188(1) (ii) and 189 of LRA. When the employers seek to review the terms and conditions of employment, the tension between these sections becomes more common, as it involves the matters of mutual interest which are dealt with through the collective bargaining arena and the dispute of right through arbitration. In Fry’s Metals v Numsa the court rejected the notion that there is tension between section 187(1) (c) and section 188(1) (a) (ii) of the LRA. Instead the court was of the view that, there is a historical context to section 187(1) (c) which is the now repealed 1956 Labour Relations Act. The 1956 LRA included in its definition of a lock-out the termination by the employer. Secondly, the court interpreted section 187(1)(C) to only give protection to employees who are dismissed in order to compel them to accept a demand on a matter of mutual interest, and only where the dismissal was of a temporary nature. The court interpretation in Fry’s metals implied that, section 187(1)(c) will only come to the defence of employees if they are dismissed for the purpose compelling them to accept a demand on a matter of mutual interest, and if the dismissal was of a temporary nature. Where a permanent dismissal is effected because employees would not accept its demands, section 187(1) (c) could not come to the employees’ protection. Considering that the lock out provided for in terms of the 1995 LRA is not a preferred option by most of the employers, they will rather resort to use the loophole created by the narrow interpretation of section 187(1)(c) to circumvent having to secure consensus from the affected employees and rather dismissed them based on operational requirements. This study seeks to deal with the questions relating to the relationship between collective bargaining related dismissals in particular the automatically unfair dismissal in terms of section 187(1) (c) and business restructuring related dismissal. As such the relationship between sections 187(1) (c) and dismissals based on operational requirements will be central to this study.
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  • Date Issued: 2017

Distributed leadership in South Africa

  • Authors: Grant, Carolyn
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/281024 , vital:55684 , xlink:href="https://doi.org/10.1080/13632434.2017.1360856"
  • Description: Distributed leadership, while an established concept in the international literature on education leadership, is slowly gaining prominence in post-apartheid South Africa. This is primarily due to its normative and representational appeal. However, of concern is that the concept has become a catch-all phrase to describe any form of devolved or shared leadership and is being espoused as ‘the answer’ to the country’s educational leadership woes. Drawing on a South African publications-based doctoral study of distributed teacher leadership (Grant 2010. “Distributed Teacher Leadership: Troubling the Terrain.” Unpublished PhD diss., University of KwaZulu-Natal, Pietermaritzburg) for its evidence, this article argues for a theoretically robust form of distributed leadership conceptualised as socio-cultural practice and framed as a product of the joint interactions of school leaders, followers and aspects of their situation (Gronn 2000. “Distributed Properties: A New Architecture for Leadership.” Educational Management and Administration 28 (3): 317–338; Spillane, Halverson and Diamond 2004. “Towards a Theory of Leadership Practice: A Distributed Perspective.” Journal of Curriculum Studies 36 (1): 3–34; Spillane 2006. Distributed Leadership. San Francisco: Jossey-Bass). It endorses a sequential distributed leadership framing for the South African context and calls for further empirical studies which interrogate the complex practices of distributed school leadership. For without this theoretically robust work, the article argues, distributed leadership is likely to be relegated to the large pile of redundant leadership theories and become a passing fad.
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  • Date Issued: 2017

Distribution of culturable vibrio species in freshwater resources of Cacadu, or Tambo and Chris Hani district municipalities

  • Authors: Gaqavu, Sisipho
  • Date: 2017
  • Subjects: Vibrio--South Africa--Eastern Cape Vibrio infections--South Africa--Eastern Cape Foodborne diseases--South Africa--Eastern Cape
  • Language: English
  • Type: Thesis , Masters , Microbiology
  • Identifier: http://hdl.handle.net/10353/11571 , vital:39085
  • Description: Freshwater resources are essential to the survival of all living organisms and are used for numerous purposes such as domestic, industrial, agricultural and recreational activities. Nevertheless they are vulnerable to contamination including by pathogenic organisms. Among the pathogens distributed in water resources, diarrhoea causing pathogens such as Vibrio species are the most frequently encountered, hence, the aim of this study was to evaluate the incidence of pathogenic Vibrio species in freshwater resources in Cacadu, OR Tambo and Chris Hani District Municipalities. Water samples were collected from four rivers located in Cacadu, OR Tambo and Chris Hani District Municipalities in the Eastern Cape Province, South Africa. A total of 6 physicochemical parameterswere measured and includes: temperature, total dissolved solids (TDS), dissolved oxygen, turbidity, pH and electrical conductivity. Samples were collected between March and May 2016and concentrated using the standard membrane filtration technique and plated on TCBS agar. Yellow and green colonies on TCBS agar were enumerated as presumptive Vibrio species and expressed as CFU/100ml for each river. The identification of the presumptive Vibrio species and their antibiogram characteristics were done using both culture based and molecular techniques. The physicochemical qualities ranged as follows: pH (7.0-7.03), temperature (16 - 23 ºC), turbidity (15.6 – 43 NTU), electrical conductivity (61.1 – 835μS/cm), dissolved oxygen (7.34 – 8.73 mg/L), total dissolved solids (39.3 – 533.33 mg/L). Statistical analysis showed that pH, temperature, turbidity, dissolved oxygen were significantly different (P < 0.05), whereas the total dissolved solids were not significantly different (P ˃ 0.05) with respect to sampling sites. Vibrio densities ranged between 3.08 ×101-6.96 ×101 with Bloukrans River characterized by high counts compared to other rivers. Two hundred and three (203) positive Vibrio genus isolates were screened for speciation. Of these, the prevalent species found was V. cholerae (29percent) followed by V. vulnificus (4percent), V. fluvialis (4percent) and the least was V. parahaemolyticus (3percent). The remaining unidentified 60percent were alleged to belong to other Vibrio species not covered within the scope of this study. The antibiotic susceptibility profiles of confirmed Vibrio genus isolates recovered from the four rivers revealed that 83percent of Vibrio isolates in this study exhibited resistance againstthree or more antimicrobial agents. The presence of the following Vibrio pathogens V. fluvialis, V. cholerae, V. vulnificus and V. parahaemolyticus in water resources suggests that these water resources are significant reservoirs of Vibrio pathogens. Thus, there is a need for regular contamination monitoring programme of the selected water resources and other areas that might be of interest. In general, the results obtained from this study suggest that the river waters are not suitable for drinking, domestic or recreational use.
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  • Date Issued: 2017
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