Negotiating historical continuities in contested terrain : a narrative-based reflection on the post-apartheid psychosocial legacies of conscription into the South African Defence Force
- Authors: Edlmann, Tessa Margaret
- Date: 2015
- Subjects: South Africa. National Defence Force , Draft -- South Africa -- History -- 20th century , Draft -- Psychological aspects , Masculinity -- South Africa , Sociology, Military -- South Africa , Whites -- Race identity -- South Africa , South Africa -- Politics and government -- 1948-1994 , Narrative inquiry (Research method)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2608 , http://hdl.handle.net/10962/d1012811
- Description: For a 25-year period during the apartheid era in South Africa, all school-leaving white men were issued with a compulsory call-up to national military service in the South African Defence Force. It is estimated that 600 000 men were conscripted between 1968 and 1993, undergoing military training and being deployed in Namibia, Angola and South Africa. The purpose of this system of military conscription was to support both the apartheid state’s role in the “Border War” in Namibia and Angola and the suppression of anti-apartheid resistance within South Africa. It formed part of the National Party’s strategy of a “total response” to what it perceived as the “total onslaught” of communism and African nationalism. While recruiting and training young white men was the focus of the apartheid government’s strategy, all of white South African society was caught up in supporting, contesting, avoiding and resisting this system in one way or another. Rather than being a purely military endeavour, conscription into the SADF therefore comprised a social and political system with wide-ranging ramifications. The 1994 democratic elections in South Africa heralded the advent of a very different political, social and economic system to what had gone before. The focus of this research is SADF conscripts’ narrations of identity in the contested narrative terrain of post-apartheid South Africa. The thesis begins with a contextual framing of the historical, social and political systems of which conscription was a part. Drawing on narrative psychology as a theoretical framework, the thesis explores discursive resources of whiteness, masculinities and perceptions of threat in conscripts’ narrations of identity, the construction of memory fields in narrating memories of war and possible trauma, and the notions of moral injury and moral repair in dealing with legacies of war. Using a narrative discursive approach, the thesis then reflects on historical temporal threads, and narrative patterns that emerge when analysing a range of texts about the psychosocial legacies of conscription, including interviews, research, memoirs, plays, media reports, video documentaries, blogs and photographic exhibitions. Throughout the thesis, conscripts’ and others’ accounts of conscription and its legacies are regarded as cultural texts. This serves as a means to highlight both contextual narrative negotiations and the narrative-discursive patterns of conscripts’ personal accounts of their identities in the post-apartheid narrative terrain. The original contribution of this research is the development of conceptual and theoretical framings of the post-apartheid legacies of conscription. Key to this has been the use of narrative-based approaches to highlight the narrative-discursive patterns, memory fields and negotiations of narrative terrains at work in texts that focus on various aspects of conscription and its ongoing aftereffects. The concept of temporal threads has been developed to account for the emergence and shifts in these patterns over time. Existing narrative-discursive theory has formed the basis for conscripts’ negotiations of identity being identified as acts of narrative reinforcement and narrative repair. The thesis concludes with reflections on the future possibilities for articulating and supporting narrative repair that enables a shift away from historical discursive laagers and a reconfiguration of the narrative terrain within which conscripts narrate their identities. , Also known as: Edlmann, Theresa
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- Date Issued: 2015
Low symmetry metallophthalocyanines and their nanoparticle conjugates for photodynamic antimicrobial chemotherapy
- Authors: Masilela, Nkosiphile
- Date: 2013
- Subjects: Nanoparticles Anti-infective agents Chemotherapy Photochemotherapy Quantum dots Gold Silver , Phthalocyanines
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4278 , http://hdl.handle.net/10962/d1001906
- Description: This thesis reports on the syntheses of novel low symmetrically substituted Zn, Sn, Ge and Ti MPc complexes containing a single carboxylic or cysteinyl group available for attachments to MNPs. The complexes were extensively characterized by various techniques to ensure their purity. Various metallic nanoparticles consisting of silver (AgNPs), gold (AuNPs) as well as quantum dots (QDs) were successfully prepared and conjugated to the low symmetry phthalocyanine complexes. The conjugates were successfully characterized using many techniques. The Q-band maxima of the MPcs were observed at completely different wavelength regions depending on the nature of the substituents and the central metal used. Blue shifting of the Q band in the absorption spectra was observed for the complexes in the presence of AuNPs, while aggregation was observed in the presence of quantum dots. The complexes were successfully electrospun into polymer fibers for the antimicrobial inhibition of bacteria. The photophysical and photochemical properties of these complexes were extensively investigated. Higher triplet and singlet oxygen quantum yields were achieved for the Ge Pc complexes, with all the complexes giving reasonable singlet oxygen quantum yields. An enhancement in triplet and singlet oxygen quantum yields was observed for all the complexes in the presence of metal nanoparticles. However, the singlet oxygen quantum yields decreased for all the complexes when incorporated into electrospun fibers. The antimicrobial behaviour of the complexes was investigated against Bacillus Subtilis and Staphylococcus Aureus in solution and in the fiber matrix. High antimicrobial inhibitions were observed for the Ge complexes followed by the ZnPc derivatives. All the low symmetry ZnPc derivatives were conjugated to AgNPs and their antimicrobial behaviour was compared to their symmetrical counterparts. The best antimicrobial inhibition behaviour was observed for the low symmetry Pcs when compared to their symmetrical counterparts. In the absence and in the presence of AgNPs, axially ligated SiPc also showed better antimicrobial activity when it was compared to the unsubstituted ZnPc complex.
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- Date Issued: 2013
The development and assessment of sustained release nevirapine tablets
- Authors: Mwila, Chiluba
- Date: 2013
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54667 , vital:26598
- Description: The use of antiretroviral (ARV) agents in the management of HIV/AIDS has significantly improved the lifestyle and wellbeing of patients. Despite the success that has been achieved with the use of ARV therapy, the occurrence of adverse effects and unpredictable bioavailability associated with most of these drugs remains a major concern. Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that is used in combination with other ARV compounds for the treatment of HIV-1 infections. It is also used for the prevention of mother to child transmission of the HIV-1 virus. NVP is a Biopharmaceutics Classification System (BCS) Class II compound. Although NVP exhibits good oral absorption, it induces self-metabolism leading to low and sometimes unpredictable bioavailability. NVP is commercially available as an immediate release and extended release dosage form, viz., Viramune® XR. Formulation of a generic sustained release (SR) dosage form for once daily dosing would result in delivery of constant amount of the drug to the circulation, reduce dose related adverse effects, improve patient compliance to medication and reduce the costs of therapy. A simple RP-HPLC method was developed and optimised using a central composite design approach. The method was validated using ICH guidelines and was found to be linear, precise, specific and accurate for the analysis of NVP both in bulk and dosage forms. Direct compression was used as the method of tablet manufacture. Different polymers were assessed for suitability as rate retarding polymers and included Methocel® K4M, Carbopol® 71G NF and Eudragit® RSPO. Powder blends were assessed for flow properties using the angle of repose, bulk and tapped density, Carr’s Compressibility index and Hausner’s ratio. The traditional approach of changing the amount of polymers and diluents systematically to achieve a desired NVP release profile was used for the development of a preliminary formulation. Response surface methodology was used for the optimisation of the formulation using a Box-Behnken quadratic design. Physical characteristics of the tablets such as thickness, weight, hardness, tensile strength and friability were assessed and the tablets passed Pharmacopoeial testing. NVP assay and content uniformity were assessed using a validated RP-HPLC method. Initially, USP Apparatus 2 was used to study NVP release over a 24 hour period and subsequently dissolution studies were performed using USP Apparatus 3 as it can be used to simulate GIT conditions. The dissolution profiles generated were used to determine the agitation rate for USP Apparatus 3 that would be equivalent to an agitation rate of 50 rpm when using USP Apparatus 2. The effect of the mesh screen pore size, buffer molarity strength and concentration of surfactant on NVP release were also investigated in order to select discriminatory dissolution test conditions for the test formulation. Dissolution profiles were compared to those of the commercially available Viramune® XR using the FDA recommended difference (f1) and similarity (f2) factors. The calculated values for f1 and f2 revealed that the dissolution profile for the optimised formulation that was identified was statistically similar to Viramune® XR. In vitro release data were fitted to different kinetic models to study the release kinetics of NVP. The overall mechanism of NVP release was best described using the Korsmeyer-Peppas diffusion exponent value, n. NVP release was found to be anomalous, implying that the release was influenced by a combination of diffusion, swelling and polymer chain relaxation. The Hixson-Crowell model revealed that there was constant change in surface area of the dosage form suggesting that erosion and swelling were significant factors affecting NVP release from the hydrophilic matrix technology. The release kinetics data were also used to design the optimised formulation. Tablets manufactured using the optimised formulation were subjected to water uptake and erosion studies and the results revealed that swelling and erosion occur simultaneously. The effects of pH and molarity on the swelling and erosion of the tablets were also investigated. The data suggest that increase in pH resulted in a slight increase in swelling while an increase in molarity did not have a significant effect on swelling. The change in pH did not have a significant effect on erosion while an increase in molarity strength resulted in a decrease in matrix erosion. The effect of HPMC grade on swelling, erosion and NVP release revealed that the grade of HPMC used had a significant effect on NVP release, with the release rate decreasing, swelling increasing and erosion decreasing as the viscosity of the HPMC grade increased. The effect of the particle size of MCC on NVP release was also studied by manufacturing tablets containing different grades of MCC and these studies revealed that particle size did not appear to have a significant effect on NVP release. Similarly the use of different types of lactose did not appear to have a significant impact on NVP release. In conclusion a sustained release NVP tablet formulation that has the potential for further development and optimisation has been developed, assessed and manufactured successfully and has been shown to exhibit similar dissolution behaviour to Viramune® XR, a commercially available NVP extended release product.
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- Date Issued: 2013
Ecology and degree of specialization of South African milkweeds with diverse pollination systems
- Authors: Coombs, Gareth
- Date: 2010
- Subjects: Milkweeds -- South Africa Milkweeds -- South Africa -- Ecology Milkweeds -- South Africa -- Pollination Allee effect Self-pollination Pollination by insects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4189 , http://hdl.handle.net/10962/d1003758
- Description: Like orchids, the complexity of flowers found in asclepiads (Asclepiadoideae, Apocynaceae) and the fact that pollen is presented as pollinaria, offers excellent opportunities to study various aspects of plant-pollinator interactions. In this thesis I investigated two broad themes: ecological aspects of the pollination biology of hymenopteran and fly-pollinated asclepiads as well as the degree of specialization to certain pollinators in these species. Colonizing plants often reproduce through self-pollination, or have highly generalized pollination systems, or both. These characteristics facilitate establishment in small founding populations and generates the prediction that reproductive success should be independent of population size in these species. Chapter one examines the pollination biology of Gomphocarpus physocarpus, an indigenous, weedy species and investigates the relationship between reproductive success and population size. In this species, there is no evidence of an Allee effect and reproductive success is not correlated with population size. In addition G. physocarpus is not capable of self-pollination, suggesting it is completely reliant on pollinators for seed set. The lack of a relationship between pollination success and population size is therefore likely explained by the generalized wasp pollination system of this species. Several milkweeds are invasive outside of their native ranges. Invasive species either need to co-opt native pollinators in order to reproduce or reduce their reliance on pollinators through having the ability to self-pollinate. Co-opting native pollinators is expected to be easier in species that have generalized pollination systems, alternatively species with specialized flower morphologies need to rely on similar functional groups of pollinators to be present within the invaded range. Chapter two investigates the pollination biology and pollination success of the invasive milkweed, Araujia sericifera, and finds that in South Africa, this species is visited mainly by native honeybees and nocturnal moths. Moths however contribute little to pollen removal, and deposition. Based on the apparent morphological mismatch between the flower of A. sericifera and native honeybees, I propose that the native pollinators of this species are likely to be larger Hymenoptera (e.g. Bumblebees). Data from a breeding system study, indicated that this species is not capable of automatic self-pollination, but could set fruit from geitonogamous self-pollinations pointing to the importance of native pollinators for successful reproduction. The pollinaria of milkweeds can accumulate on pollinators to form pollen masses large enough to physically interfere with the foraging behaviour of pollinating insects. In chapter three I describe the pollination biology of Cynanchum ellipticum and find that this species is mainly pollinated by honeybees although this species is visited by several other members of Hymenoptera, Lepidoptera and Diptera. Due to the structure of the pollinaria, these chain together relatively efficiently and frequently form large pollinarium loads on the mouthparts of honeybees. However there is little evidence that these pollinarium loads influence the foraging times of pollinators and only a few individual honeybees exhibited longer foraging times and most honeybees were unaffected by the presence of large pollinarium loads. Within the genus Cynanchum there is large variation in the gynostegium structure that may influence the pattern of pollinarium loading on pollinators as well as pollen reception as shown in chapter three. In Chapter four, the pollination biology of Cynanchum obtusifolium is examined, and like that of C. ellipticum, this species is visited by a wide diversity of pollinators but honeybees appear to be the primary pollinators. More importantly this species is shown to be andromonoecious and produces two morphologically different flower types, that may be distinguished based on differences in the gynostegium structure. These two types of flower could mainly be distinguished by the length of the anther wings. I found that flowers with short anther wings function as male flowers by only exporting- and rarely receiving pollinia. Flowers with longer anther wings function as hermaphrodite flowers and can both export and receive pollinia. The ratio of male to hermaphrodite flowers varied at different times during the flowering season, but preliminary data suggested that this was not related to levels of pollination success. The genera Stapelia and Ceropegia are well known for their intricate floral adaptations that mimic the brood and feeding substrates of pollinating flies. Despite several studies that have documented the various adaptations to fly pollination in different species, there is a lack of natural history studies documenting different flower visitors, pollen loads and long term levels of pollination success in these species. In Chapter six I document the pollination biology of Ceropegia ampliata by documenting different pollinators and quantifying average levels of pollination success and the nectar reward. I also experimentally manipulated the trapping hairs of this species to determine whether trapping hairs influence average levels of pollen export and receipt. I show that Ceropegia ampliata is pollinated by a generalist guild of flies (mainly Tachinidae, Sarcophagidae, Muscidae and Lauxaniidae) and produces minute quantities of relatively dilute nectar as a reward. Pollination success was generally low in this species and increases periodically suggesting that the abundance of pollinators is patchy. I found that flowers with trapping hairs that had already wilted had higher levels of pollinarium removal than flowers with erect hairs, however experimentally removing the hairs had no significant effect on pollen export and receipt. In Chapter seven, I document the pollinators, pollen loads and long term levels of pollination success in Stapelia hirsuta var. bayllissi, a rare sapromyiophilous stapeliad. I find that, in contrast to C. ampliata, this species was specialized to pollination by small flies of the family Anthomyiidae. Similar to the results from Chapter seven, I find that long term levels of pollination success were typically low but could increase periodically, although such increases were generally unpredictable. There are currently very few records documenting pollinator interactions in the Periplocoideae. Many species within this subfamily exhibit open-access flowers suggestive of pollination by short-tongued insects. I investigated the pollination biology of Chlorocyathus lobulata, a rare species with a highly localized distribution. I aimed to determine the pollinators, average levels of pollination success and demography of this species in order to determine whether this rare species is suffering from the collapse of a highly specialized pollinator mutualism. I also quantified the high incidence of flower herbivory caused by larvae of the moth, Bocchoris onychinalis. I find that C. lobulata has a highly generalized fly pollination system and average levels of pollination success suggested that a large proportion of flowers had pollen removed and deposited suggesting that this species is not experiencing pollination failure. The large numbers of juveniles present also indicated that recruitment is taking place.
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- Date Issued: 2010
Social media reviews to investigate restaurant dinning experiences
- Authors: Van Achterbergh, Leon
- Subjects: Hospitality industry -- Social aspects , Restaurants -- Social aspects , Social media -- Economic aspects , Consumers -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9349 , http://hdl.handle.net/10948/d1021126
- Description: Restaurateurs often assume that customers' online reviews of their dining experiences are a reflection of their dining preferences. This study finds this assumption not to be true. Online written reviews do not explain diners’ preferred dining experiences. In this study post-experience reactions captured in reviews are shown to be contextually different to established dining preferences. Results show online reviews to be most important in facilitating customer dining expectations, but not influencing customers’ preferences in dining experiences. Evidence gathered during the secondary research shows that in general, social media has become the great marketing equaliser in commerce. In the dining industry, restaurants cannot solely rely on traditional media in the initial attraction and retention of dining customers. Continuous interaction between the business and customers is increasingly necessary for restaurateurs to remain competitive and in-touch with customers’ needs. This study concentrates its research area on the post-experience evaluation phase as found on review websites, like TripAdvisor. TripAdvisor has especially become a popular means to perpetuate word-of-mouth opinions of dining experiences among prospective customers. Research shows clear evidence of the importance of other's online opinions in the consumer decision-making process. The main variables of the study, namely customer experiences, restaurant dining and social media, are theoretically explored within the disciplines of service management and customer behaviour. These theories have laid a sound foundation for the subsequent research methods followed. The main purpose of the study was using social media reviews from TripAdvisor to investigate dining experiences in the restaurant industry. The outcomes desired were: firstly to advise the restaurant industry about superior customer practices, secondly emphasising the importance for industry of social media use in the dining experience, and thirdly rendering clarification on the experience perceptions of customers about factors that might lead to ‘delight’ and ‘frustration’. This research centralises the constructs of delight and frustration factors, which are typically extremely emotional dining experiences for the customer, that have the common element of surprise. Methodologically, the research required two phases: firstly, the qualitative analysis of online user-generated content by content analysis. The global sample consisted of seven international cities, which included the best, worst and average-rated TripAdvisor restaurant reviews. The content analysis produced the theoretical base for the dining perception variables used in the empirical survey. In the second phase of the study, the global surveys administered resulted in measuring the general public’s perceptions of the delight and frustration factors of dining experiences. Subsequently, the research process required various quantitative data analyses to reach substantial results with inferences. The results and interpreted findings achieved were twofold: Firstly, from the content analysis: customers regard service quality as relatively unimportant in relation to the holistic dining experience. Customers regarded food and beverage quality as crucial in the dining experience. Value for money increasingly becomes an issue as customers become more frustrated, more so than when the dining was generally experienced as pleasant. Secondly, from the empirical data: mood and aesthetics are essential, especially when diners chose between their favourite restaurants. Further results show managing the service basics for restaurants is essential; this included welcoming, professional, attentive and friendly service. Service consistency has also proven to be imperative in customers’ perceptions. Results further show that different nationalities could perceive food quality and service reliability differently. In addition, men and women could perceive food quality, mood and aesthetics, and value for money differently. This study recommends various findings to the restaurant industry: most importantly that the post-experience reviews are contextually different to customers’ dining preferences. The factor determining the reputation of a restaurant is food quality and not so much service quality. Value for money should be associated with a specific service or product feature for it to be of meaningful consequence to the restaurateur.
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