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The evolution of a security community through a process of integration: problems and prospects for the SADC region

  • Authors: Šebek, Vita
  • Date: 2002
  • Subjects: Political stability -- Africa, Southern , Southern African Development Community , National security -- Africa, Southern , Africa, Southern -- Economic integration
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2831 , http://hdl.handle.net/10962/d1003041
  • Description: This thesis examines the security problematic of African states and focuses more particularly on the SADC region. It links the security problematic with the transactionalist approach to (supra)national integration and the concept of a security community, introduced into internatIonal relations theory by Karl Deutsch and his colleagues. In relation to the (in)security of SADC member states, the thesis attempts to demonstrate that national integration of these states (i.e. the establishment of an amalgamated security community) has at least to accompany if not precede the establishment of a security community at the regional level (i.e. a pluralistic security community). Since threats to the security of SADC member states are mainly nonmilitary in nature, the 'realist' concept of security is broadened to include political, economic, societal and environmental aspects of security at different levels. Furthermore, Deutsch's concept of a security community is redefined in line with the 'new security thinking' and adapted to the situation in African states. Moreover, this thesis attempts to demonstrate that it is essential for SADC member states to become strong and socio-economically cohesive in order to improve their competitiveness in relation to developed states, especially in their ability to deal with internal and ransnational/regional threats to their security, which are (in)directly caused and perpetuated by the lack of national integration, inefficient state-making and underdevelopment - the sources of their weakness.
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An understanting of mirrors and mirroring in a schizophrenic patient obsessed with his appearance

  • Authors: Zworestine, Barry John
  • Date: 1993-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10962/191702 , vital:45149
  • Description: This work addresses the role of mirroring and mirrors encountered while working with a patient obsessed with his appearance. At the same time, however, it also attempts to provide an understanding of the process of mirroring from the developing unborn child to the adult. It examines the womb as a reflective space, the mirroring role of the mother, psychological work as mirror work, the psychopathologies of disruptive mirroring and the nature of reflection as a story, confusion and a ghostly other, and finally, the relationship between mirror reflection and psychological life. What is examined and described in this process applies not only to the specific case in study but is relevant at a universal level to all of mankind regardless of race or religion. The case-study method was used to examine the process of therapy that took place over three months. The patient’s identifying data, reasons for referral, presenting problem, family background, basic personality, interpersonal relationships, mental state, diagnosis, dynamic formulation and rationale for psychotherapy were covered in detail. The process of psychotherapy over 27 sessions was recounted and discussed in detail. Theoretical understandings drawn on to facilitate an understanding of the case were from Davis and Walbridge on Winnicolt, Winnicot, Liedloff, Kay, Romanyshyn, Bettelheim, Schwartz and others. , Thesis (MA) -- Faculty of Humanities, Psychology, 1993
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Leveraging LTSP to deploy a sustainable e-infrastructure for poor communities in South Africa

  • Authors: Zvidzayi, Tichaona Manyara
  • Date: 2022-10-14
  • Subjects: Linux Terminal Server Project , Network computers , Thin client , Fat client , Cyberinfrastructure , Poverty reduction
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/365577 , vital:65761
  • Description: Poverty alleviation is one of the main challenges the South African government is facing. Information and knowledge are key strategic resources for both social and economic development, and nowadays they most often rely on Information and Communication Technologies (ICTs). Poor communities have limited or no access to functioning e-infrastructure, which underpins ICT. The Siyakhula Living Lab (SLL) is a joint project between the universities of Rhodes and Fort Hare that has been running for over 15 years now. The SLL solution is currently implemented in schools in the Eastern Cape’s Dwesa-Mbhashe municipality as well as schools in Makhanda (formerly Grahamstown). Over the years, a number of blueprints for the meaningful connection of poor communities was developed. The research reported in this thesis sought to review and improve the Siyakhula Living Lab (SLL) blueprint regarding fixed computing infrastructure (as opposed to networking and applications). The review confirmed the viability of the GNU/Linux Terminal Server Project (LTSP) based computing infrastructure deployed in schools to serve the surrounding community. In 2019 LTSP was redesigned and rewritten to improve on the previous version. Amongst other improvements, LTSP19+ has a smaller memory footprint and supports a graphical way to prepare and maintain the client’s image using virtual machines. These improvements increase the potential life of ICT projects implementing the SLL solution, increasing the participation of members of the community (especially teachers) to the maintenance of the computing installations. The review recommends the switching from thin clients deployments to full ("thick") clients deployments, still booting from the network and mounting their file systems on a central server. The switch is motivated by reasons that go from cost-effectiveness to the ability to survive the sudden unavailability of the central server. From experience in the previous deployment, electrical power surge protection should be mandatory. Also, UPS to protect the file system of the central server should be configured to start the shutdown immediately on electrical power loss in order to protect the life of the UPS battery (and make it possible to use cheaper UPS that report only on network power loss). The research study contributed to one real-life computing infrastructure deployment in the Ntsika school in Makhanda and one re-deployment in the Ngwane school in the Dwesa-Mbhashe area. For about two years, the research also supported continuous maintenance for the Ntsika, Ngwane and Mpume schools. , Thesis (MSc) -- Faculty of Science, Computer Science, 2022
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Investigation of the potency of topical corticosteroids using the vasoconstrictor assay

  • Authors: Zvidzayi, Kudzayi Michael
  • Date: 2017
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/65279 , vital:28717
  • Description: Expected release date-May 2019
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The influence of individual employee performance metrics on a sub-culture in a professional services firm in Durban, South Africa

  • Authors: Zvarevashe, Marshall
  • Date: 2013
  • Subjects: Performance -- Evaluation Corporate culture -- South Africa Organizational effectiveness Leadership Management -- South Africa Organizational behavior -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:714 , http://hdl.handle.net/10962/d1001868
  • Description: In today’s fast paced and global economy, competitive advantage is increasingly focused more on organisational behaviours rather than on the traditional tenets of land, labour and capital. Going beyond the traditional, organisations that are best able to get the most and the best out of their people are the ones most likely to perform better. This study aims to build an understanding of how culture is influenced by individual employee performance metrics that are used in an organisation. Previous research has been done in the broad fields of organisational culture and employee performance metrics separately, but no studies were identified in literature that focused on the interaction of the two concepts specifically. Therefore, this study seeks to answer the following research question: How do individual employee performance metrics influence sub-culture in the context of a professional services firm in Durban? This study predominantly focused not on performance at the organisational level, but rather the more granular level of individual employee performance metrics and sub-culture in one of the divisions of a professional services firm. This qualitative study explores the multiple perspectives of reality of ten of the 32 managers in the Advisory division of a professional services organisation, regarding how individual employee performance metrics influence their world view of work, or the way they perceive, think, feel and interact in the world of work. The focus of the study was limited to one department, in one branch of a multinational organisation and focused only on the horizontal layer of the “manager group” within the staff levels. Semi-structured, in-depth and face-to-face interviews were conducted with these managers as a means of gathering and saturating data. Interviewees were identified using a stratified sampling from the group of managers in the Advisory division. Open coding and constant comparison was used to analyse data. Page ii of viii The results of the study show that managers had very varied and complex perceptions of how the individual performance metrics used to assess their performance influence the sub-culture of their world of work. The key findings manifested that misuse and abuse of performance metrics by leaders, leadership bias in respect to recognition, reward and remunerations, the predominant focus of the division on the bottom line and emphasis on success at all cost, and low employee morale were all aspects of performance that impacted on how employees behaved in the division. The effect of these factors on the managers operating in this division was that there were low levels of employee commitment which were experienced through low morale and reduced productivity; managers felt that there was a restriction in the development of their careers, all of which resulted in a disregard to values of the organisation. This study reflects how the reward and recognition system using the balanced scorecard has shifted the focus of the department away from the organisation’s espoused values. This has resulted in various leadership and management questions for the leadership of the division in this study. This research also adds to existing literature that links performance and culture within the organisational context that it goes beyond the prevalent themes in literature which focus on performance at the organisation level. This study focuses on performance at the employee level and in particular in a professional services firm in South Africa. The study has three interrelated sections which are however considered as standalone. The first section is an evaluation report based on the Advisory division of a professional services firm in Durban, South Africa, and consists of a literature review, the methodology followed in conducting the study, results and the discussion thereof. The report also highlights limitations of the study, recommendations and the perceived value of the study. The report ends with a summary in the form of a conclusion. Section 2 comprises a more comprehensive literature review while Section 3 documents the research methodology followed in the study.
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Microbial ecology of the Buffalo River in response to water quality changes

  • Authors: Zuma, Bongumusa Msizi
  • Date: 2010
  • Subjects: Water quality -- South Africa -- Buffalo River (Eastern Cape) , Microbial ecology -- South Africa -- Buffalo River (Eastern Cape) , River Health Programme (South Africa)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:6038 , http://hdl.handle.net/10962/d1006182 , Water quality -- South Africa -- Buffalo River (Eastern Cape) , Microbial ecology -- South Africa -- Buffalo River (Eastern Cape) , River Health Programme (South Africa)
  • Description: South Africa’s freshwater quality and quantity is declining and consequently impacting on the ecological health of these ecosystems, due to increased agricultural, urban and industrial developments. The River Health Programme (RHP) was designed for monitoring and assessing the ecological health of freshwater ecosystems in South Africa, in order to effectively manage these aquatic resources. The RHP utilises biological indicators such as in-stream biota as a structured and sensitive tool for assessing ecosystem health. Although the RHP has been widely implemented across South Africa, no attempts have been made to explore microbial ecology as a tool that could be included as one of the RHP indices. This study used selected microbial responses and water physico-chemical parameters to assess the current water quality status of the Buffalo River. This study showed that water quality impairments compounded in the urban regions of King William’s Town and Zwelitsha and also downstream of the Bridle Drift Dam. The results also showed that the lower and the upper catchments of the Buffalo River were not significantly different in terms of water physico-chemistry and microbiology, as indicated by low stress levels of an NMDS plot. Though similarities were recorded between impacted and reference sites, the results strongly showed that known impacted sites recorded the poorest water physico-chemistry, including the Yellowwoods River. However, the Laing Dam provided a buffer effect on contributions of the Yellowwoods River into the Buffalo River. Multivariate analysis showed that microbial cell counts were not influenced by water physico-chemical changes, whilst microbial activity from the water and biofilm habitats showed significant correlation levels to water physico-chemical changes. This study demonstrated that further investigations towards exploitation of microbial activity responses to water physico-chemical quality changes should be channelled towards the development of microbiological assessment index for inclusion in the RHP.
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Synthesis, characterization and antiparasitic evaluation of chalcone hybrids

  • Authors: Zulu, Ayanda Ignatia
  • Date: 2021-10-29
  • Subjects: Uncatalogued
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/192853 , vital:45271
  • Description: Thesis (PhD) -- Faculty of Science, Chemistry, 2021
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Synthesis and evaluation of arylpyrrole-chalcone hybrids as antiplasmodial and antitrypanosomal agents

  • Authors: Zulu, Ayanda Ignatia
  • Date: 2017
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/65268 , vital:28716
  • Description: Expected release date-May 2019
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Phototransformation of pollutants using lutetium and zinc phthalocyanines anchored on electrospun polymer fibers

  • Authors: Zugle, Ruphino
  • Date: 2013
  • Subjects: Electrospinning Phthalocyanines Lutetium Zinc Polymers Dysprosium Pollutants Air Pollution Photochemistry
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4286 , http://hdl.handle.net/10962/d1002962
  • Description: Novel lanthanide phthalocyanines containing dysprosium, erbium and lutetium as central metals were synthesized using phthalonitrile:metal salt ratio of 4:1 or lower phthalonitrile content as well as using unmetallated phthalocyanine. They were characterized using various spectroscopic and elemental analyses. Dysprosium bis-phthalocyanine was obtained while monomers were obtained for erbium and lutetium phthalocyanines. Theopen-shelldysprosiumbis-phthalocyanine and the monomeric complex of the open-shell erbium were neither fluorescent nor showed the ability to generate singlet oxygen. The triplet states of all the lutetium phthalocyanines were found to be populated with high triplet quantum yields and corresponding high singlet oxygen quantum yields. The fluorescence quantum yields of the lutetium phthalocyanines were however found to be very low. The lutetium phthalocyanines together with unsubstituted zinc phthalocyanine and its derivatives were successfully incorporated into electrospun polymer fibers either by covalent linkage or sorption forces. Spectral characteristics of the functionalized electrospun polymer fibers indicated that the phthalocyanines were bound and their integrity maintained within the fiber matrices. Most importantly the fluorescence and photoactivity of the phthalocyanines were equally maintained within the electrospun fibers. The functionalized electrospun polymer fibers especially those containing the zinc phthalocyanines could qualitatively detect nitrogen dioxide, a known environmental air pollutant. Also all the functionalized electrospun polystyrene and polysulfone fibers containing lutetium and zinc phthalocyanines could be applied for the photoconversion of 4-chlorophenol, 4-nitrophenol and methyl orange. Those of polystyrene could be re-used. Polyacrylic acid and polyurethane functionalized electrospun fibers were found not to be suitable for photocatalytic applications in aqueous medium. 4-Chlorophenol was found to be more susceptible to photodegradation while methyl orange very difficult to degrade.
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The use of the cochineal insect, Dactylopius tomentosus Lamarck, as a biological control agent for the invasive alien thistle cholla, Cylindropuntia pallida (Rose) F.M. Knuth in South Africa

  • Authors: Zozo, Ekhona
  • Date: 2022-04-06
  • Subjects: Cochineal insect , Thistles Biological control South Africa , Alien plants South Africa , Invasive plants South Africa , Cactus South Africa , Biological assay
  • Language: English
  • Type: Master's thesis , text
  • Identifier: http://hdl.handle.net/10962/233823 , vital:50131
  • Description: Cylindropuntia pallida (Rose) F.M. Knuth (Cactaceae) is an invasive alien plant in South Africa indigenous in the southern U.S.A. and Mexico. Large infestations of this species can be found in the Kalahari and arid Karoo regions of South Africa, which is also present in Namibia. Because it is a very spiny cactus, dense infestations have a negative impact on agriculture and natural ecosystems. This cactus has become naturalised to the extent that eradication is impossible and the negative impacts are steadily increasing due to its increasing distribution and density. The cochineal insect, Dactylopius tomentosus Lamarck (Dactylopiidae), is native in Mexico and parts of North America, such as Texas, Arizona, and New Mexico in the U.S.A. This cochineal species is highly specialized and associated only with Cylindropuntia species, a group of cacti that are primarily restricted to the same areas. It has been introduced into Australia and South Africa as a biological control agent to control various invasive alien Cylindropuntia species. This cochineal species has several biotypes specific to certain Cylindropuntia species hosts. A biotype is a clade that cannot be differentiated morphologically from others but has different host ranges and impacts depending on the host plant species. Included amongst biotypes that have been released in South Africa are D. tomentosus ‘imbricata’ and D. tomentosus ‘cholla’ for the biological control of Cylindropuntia imbricata (Haw.) F.M. Knuth (Cactaceae) and Cylindropuntia fulgida (Engelmann) F.M. Knuth var. mamillata (Schott ex Engelmann) Backeb. (Cactaceae), respectively. These biotypes have resulted in both host plants being under substantial control in South Africa. The first part of this thesis evaluated which of the two D. tomentosus biotypes already in use in South Africa could be an effective biological control agent for C. pallida. This was done by assessing the fitness of the cochineals on the three cactus species and assessing the impact that each of the cochineals has on each of the target weed species. Should these biotypes prove ineffective, there is a third biotype, namely D. tomentosus ‘californica var. parkerii’, which researchers in Australia have worked on and have found to be suitably host-specific for release in Australia and suitably damaging to C. pallida in that country. Therefore, this new biotype could be released in South Africa if it is required. Sexually compatible biological control agents, especially those closely related and occurring in close spatial proximity to one another, may interbreed and the impacts of this hybridisation are difficult to predict. It is important to understand the outcomes of the hybridisation of cochineal because it can affect the impact of the biological control agents and thus the control of the target weed. The second part of this thesis investigated the impacts of the hybridisation of the two cochineal biotypes by assessing the damage the agents would have on the target weed, and on C. imbricata and C. fulgida var. mamillata, in the presence of one or both cochineal biotypes. The ‘cholla’ biotype performed better on C. pallida than the ‘imbricata’ biotype, but neither biotype could control C. pallida to an extent similar to the control they provide for their respective target weeds, C. imbricata and C. fulgida var. mamillata. Both the ‘cholla’ biotype and hybrids of the two biotypes of cochineal were effective at killing C. pallida when both C. imbricata and C. fulgida var. mamillata were also present. This suggests that the ‘cholla’ or hybrids may be effective at controlling C. pallida when either C. imbricata or C. fulgida var. mamillata are also present in the field due to the high population density of cochineal that results under these circumstances. There are, however, many C. pallida infestations in South Africa where the plant is problematic and is isolated from other Cylindropuntia species, and these populations are unlikely to be controlled by the ‘cholla’ biotype or the hybrids. Neither of the cochineal biotypes that are used for biological control in South Africa are suitably damaging to C. pallida to warrant their use as biological control agents for this species. Dactylopius tomentosus ‘californica var. parkerii’ is therefore recommended for release based on its host-specificity and impact to C. pallida in Australia. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
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A case study of how a leader shaped the culture of an organisation during a post-merger integration

  • Authors: Zozi, Vuyokazi
  • Date: 2020
  • Subjects: Corporate culture -- South Africa -- East London , Leadership -- South Africa -- East London , Organizational behavior -- South Africa -- East London , Strategic planning -- South Africa -- East London , Mission statements -- South Africa -- East London , Government accountability -- South Africa -- East London , Government corporations -- South Africa -- East London , Consolidation and merger of corporations -- South Africa -- East London , Consolidation and merger of corporations -- Management , Crisis management -- South Africa -- East London , Core competencies -- South Africa -- East London , Resource allocation -- South Africa -- East London , Personnel management -- South Africa -- East London , Communication in management -- South Africa -- East London , Qualitative research
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10962/146643 , vital:38544
  • Description: This research took the form of a case study of the post-merger integration of a government organisation. The study had four objectives, namely to: (1) describe the cultural value of accountability; (2) analyse how strategic leadership and relational leadership roles were exercised to address post-merger integration challenges; (3) analyse how a leader applied selected primary mechanisms to shape organisational culture; (4) analyse how strategic and relational leadership complemented each other in addressing the challenges of post-merger integration and thereby shaping a culture of accountability; and (5) describe how some of the secondary articulation and reinforcing mechanisms supported the culture that was created through primary mechanisms. The literature reviewed, identified some of the critical challenges that are experienced in a post-merger integration, and highlighted the role of leadership in culture formation. The critical challenges that were identified are as follows: What is the vision and organisational purpose? How does the leader structure the organisation? What kind of culture does the leader need to create? How does the leader maintain trust and keep communication with employees? How does a leader build new core competences and develop human capital? Two leadership approaches were adopted, namely strategic and relational leadership. These two leadership approaches were selected because, based on a review of the literature, they appeared to address these post-integration challenges. The roles associated with strategic leadership that were investigated, were creating a vision and purpose for the organisation, developing core competences and developing human capital. From the perspective of relational leadership, this study was concerned with how a leader communicated through regular formal and informal dialogues to keep employees abreast of things, and how the leader built trust. In reviewing the literature linking leadership and culture, the work of Schein (2010) featured prominently. Schein (2010) referred to primary embedding mechanisms that create culture and secondary articulation and reinforcing mechanisms that reinforce or support the culture being created through the primary mechanisms. This study looked at how that happens, and hence six propositions were crafted from the literature. These propositions are as follows: (1) Formal dialogues between the leader and employees demonstrate what the leader pays attention to, measures and controls, which then clarifies what the employees are accountable for. (2) What the leader pays attention to, measures and controls during regular informal interactions between the leader and employees, contributes to strong mutual relationships between them, which promotes ownership and accountability amongst employees for their actions. (3) A leader who behaves consistently when handling critical incidents and organisational crises, is trusted by employees, who then act responsibly and take full responsibility for their actions, and even their mistakes. (4) A leader creates a vision and sense of purpose for the organisation through what he pays attention to, measures and controls, thereby clarifying for employees what they are required to do. (5) A leader who pays attention to developing the organisational core competence and allocates resources to it, instils confidence in his employees with regards to carrying out their own responsibilities. (6) A leader who develops human capital through the allocation of additional resources, thereby instilling confidence in employees who are willing and able to realise or take up their responsibilities. This research adopted a qualitative approach. Data was collected through conducting interviews and the analysis of relevant documents. A deductive thematic analysis of the data was used for the purpose of identifying, analysing and reporting patterns, or themes within the data collected. The research confirmed these propositions as being relevant to the case study. It also confirmed that strategic and relational leadership as reflected in the propositions have complemented one another in the successful implementation of the post-merger integration, thereby shaping a particular culture. It was concluded that the challenges associated with a post-merger integration could not have been addressed through only one of the leadership approaches. The findings of the study also recognised that an architectural role was also required. That is, in a merger, the structure has to be carefully designed and not taken for granted. It was therefore recognised as a critical leadership role. The study considers the implications of the findings and makes recommendations for managers of this organisation, as well as for other organisations that are engaging in a post-merger integration. It further outlines the limitations, delimitations as well as the contribution that the study has made to the body of knowledge. Some of the recommendations made for further research were to analyse how other primary mechanisms that were not part of the propositions may shape the organisational culture; and to research how architectural leadership roles combine with strategic and relational leadership to address post-merger integration challenges. Lastly, this study has explained how leadership, through various mechanisms, shaped a culture of accountability. Other studies can be done using a similar design with different theories of leadership and other mechanisms that apply to shaping other kinds of cultural values.
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Redefining success : social justice and the ends of business

  • Authors: Zorn, Gwendolyn Philippa
  • Date: 2014
  • Subjects: Success Social justice Success in business Social responsibility of business Business ethics Corporate profits
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2745 , http://hdl.handle.net/10962/d1012061
  • Description: Success in business is for the most part defined in financial terms and, because of this, business operations are almost entirely, if not entirely, directed to this end. The principle behind this rationale has been informed by the thought that the best contribution businesses can make to social justice is to focus on the bottom line. By appealing to enlightened self-interest and the high premium people place on freedom, neoliberal economists like Milton Friedman and Friedrich Hayek argue that maximising profits is necessarily socially responsible. And, moreover, that not to pursue this end is socially irresponsible. Social responsibility is the ultimate justification that thinkers such as Friedman and Hayek appeal to when claiming that the business of business is to maximise profit. Yet this position is internally inconsistent. The position is ultimately justified by what is socially just but this means that in fact social justice, and not profit-making, ought to be the end of business. I shall argue that taking this commitment seriously involves rejecting the idea that the aim of business is to maximise profits. This is not to say that businesses should not make profits, rather it implies that this feature is not what ultimately makes them successful. The central contribution of this project is to resolve the contradictions embedded in the traditional approach to business by arguing that the primary aim of business is the promotion of social justice. To this end success in business needs to be redefined so that it reflects the achievement of its ultimate ends and not simply its instrumental means (profit) to the realisation of these aims. We ought then to revise our fundamental assumptions about the structures and policies that are necessary for business to achieve its real end of social justice.
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Ukubamba Umphefumlo Kukuphila: Ingqokelela Yamabali Amafutshane

Tolerance of selected riverine indigenous macroinvertebrates from the Sabie River (Mpumalanga), and Buffalo River (Eastern Cape) to complex saline kraft and textile effluents

  • Authors: Zokufa, T S
  • Date: 2001
  • Subjects: Water quality management -- South Africa -- Sabie River , Water -- South Africa -- Analysis , Water -- Toxicology -- South Africa , Mayflies -- South Africa , Freshwater invertebrates -- South Africa -- Ecology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5787 , http://hdl.handle.net/10962/d1005475
  • Description: Whole Effluent Toxicity (WET) testing has been identified as one of the tools in the management of complex effluents in aquatic ecosystems. In South Africa, toxicity testing has not been required for regulatory purposes. Recently, the Department of Water Affairs and Forestry has adopted WET testing as a tool to evaluate the suitability of hazardous effluent for discharge into receiving environments. This has necessitated suitable procedures to be established for use in the South African situation. With the implementation of the new National Water Act (No 36 of 1998), industries have to comply with set standards to protect the aquatic environment. However, the South African Water Quality Guidelines for Aquatic Ecosystems have been set using international toxicity data, and it is not known if they are comparable with South African conditions. The aim of this study was to investigate the tolerances of selected indigenous riverine invertebrates to complex saline effluents. The study investigated the effects of kraft mill effluent to Tricorythus tinctus, a tricorythid mayfly from the Sabie River, Mpumalanga, and the effects of a textile effluent to baetid mayflies of the Buffalo River, Eastern Cape. Indigenous riverine invertebrates were chosen as test organisms, as there is no toxicity data in South Africa which could be used to evaluate the level of protection afforded by the South African Water Quality Guidelines for Aquatic Ecosystems. The use of indigenous riverine invertebrates added the challenge of variability of a wild population, and the use of a complex effluent as toxicant added the variability of effluent composition. In this study, WET testing was used to determine the dilution of whole effluents required for discharge. Hazard-based guidelines were developed for the disposal of kraft and textile effluents. The level of environmental hazard posed by different effluent concentrations was ranked, and was related to the River Health Class. This indicated effluent concentrations that may be allowed to enter the aquatic environment, e.g. 3% effluent concentration guideline for both general kraft effluent and general textile effluent for the protection of a Class A river. This approach could contribute to the use of an Environmental Risk Assessment, approach for the management of complex effluents. A number of acute 96 hour toxicity tests were conducted following an unreplicated regression design, using kraft and textile effluents as toxicants, mayfly nymphs as test organisms, and river water as diluent and control. Test organisms were sampled from unimpacted, flowing-water riffle areas, and were exposed in recirculating artificial streams (or channels) to a range of effluent concentrations. Mortality was selected as end-point and observed twice daily. The experimental results showed the variability and acute toxicity of both kraft and textile mill effluents. Baetids were more sensitive (mean LC50=16% effluent concentration) to General Textile Effluent (GTE), but less sensitive to Post Irrigation Textile Effluent (PITE). Textile effluent (PITE) held in a holding dam were therefore less variable and less toxic; suggesting that stabilization of the effluent could have contributed to reduced toxicity. Effluent composition, e.g. higher calcium levels, may also have contributed to lowering toxicity. T. tinctus was sensitive to kraft effluents, but showed less variable responses to Irrigation Kraft Effluent than General Kraft Effluent. Toxicity test data indicated that GKE, IKE and GTE should not enter the aquatic environment without treatment, as they can cause adverse effects to aquatic biota. Both kraft and textile effluents must therefore be treated before discharge. Different responses to different effluent batches were probably due to effluent variability. The use of indigenous organisms, and not a standard laboratory organism, could also have contributed to variability. A hazard-based approach could be useful, as it will provide a consistent basis for deciding on the acceptability of impacts, while allowing natural site-specific differences to be taken into account.
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An exploration of teacher leadership : a case study in a Namibian urban primary school

  • Authors: Zokka, Thomas Kayele
  • Date: 2013
  • Subjects: Educational leadership -- Namibia -- Kavango -- Case studies Teacher participation in administration -- Namibia -- Kavango -- Case studies School management and organization -- Namibia -- Kavango -- Case studies Education, Elementary -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1399 , http://hdl.handle.net/10962/d1001809
  • Description: After independence in 1990, Namibian schools were required by the new government to shift from a hierarchical organisational structure with authoritarian leadership to a more democratic type of leadership that offers teachers the opportunity to participate in school leadership and in decision-making processes. This shift is suggested in a number of national policies in Namibia that highlight the sharing of leadership within the organization and, in particular, the sharing of leadership with teachers. As such, teacher leadership is a manifestation of distributed leadership which emphasizes that leadership can be located in the position of the principal but can spread over many people who work in a school at various levels. While teacher leadership is well researched in developed countries, it is under researched in Namibia. Against this backdrop, the purpose of my study was to explore the concept and practice of teacher leadership as an organizational phenomenon in a case study school in the Ncuncuni circuit of the Kavango region in Namibia. It also examined the factors that enabled and inhibited the practice of teacher leadership. My study was conducted within a qualitative interpretive paradigm and it adopted a case study approach in one school. The study used the following instruments to collect data: a closed questionnaire, document analysis, observations and individual interviews. The primary participants were the principal and three teachers, while the entire school teaching staff constituted my secondary participants. Quantitative data was analysed manually using descriptive statistics while qualitative data was analysed thematically using a model of teacher leadership (Grant, 2008). The findings of my study indicated that while the concept of teacher leadership was new to all participants, they had a common sense understanding of it. Although teachers in the study understood teacher leadership in a range of different ways, the overarching idea of the whole school was that teachers lead both in and outside the classroom. My study also found that teachers in the school practiced teacher leadership across the entire four zones. These included how teacher leadership was practiced inside the classroom and how teachers worked as leaders with colleagues and learners beyond their classroom in curricular and extra-curricular activities. It also included how teachers led outside their classroom in whole school development as well as how teachers led beyond their schools in the community. Teacher leadership was strong in the first three zones and weaker in the fourth zone, which constituted an example of 'successful teacher leadership' (Harris and Muijs, 2005). There were factors that promoted teacher leadership in the case study school such as a supportive culture and ongoing professional development. Factors that constrained the practice of teacher leadership were also evident like the SMT who used its power at times to control teachers' decisions and a lack of time also emerged as a barrier that impeded teachers from taking leadership roles because they already had full teaching programmes. Even though there were some barriers to teacher leadership, a dispersed distributed leadership context prevailed at the case study school.
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Presentation and representation of environmental problems and problem-solving methods and processes in the Grade 10 Geography syllabus: a Namibian case study

  • Authors: Zokka, Herman Kankara
  • Date: 2016
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2074 , http://hdl.handle.net/10962/d1021253
  • Description: Environmental issues in Namibia are considered to be one of the major threats to the lives of the Namibian people (Namibia. Ministry of National Planning Commission [MNPC], 2004). This study explored problem solving as one of the teaching methods used in Grade 10 Geography syllabuses as a response to such environmental issues/risks. Geography provides learners with an understanding of the issues and risks in their world that need to be addressed in order to improve the quality of their lives and health of their environment. This study focused on how environmental problems and problem-solving methods are presented in the Namibian Grade 10 Geography syllabus and how these are represented and implemented through teacher intentionality and practice. The theoretical framework for this study was informed by two theories namely risk society and social constructivism. This study was conducted at three schools in the Rundu circuit in the Kavango region and one teacher was involved in the study at each school. This study was conducted within an interpretive research tradition and was qualitative in nature. The study used document analysis, focus group discussion and classroom observation as data generation methods. The findings of the study reveal that the complexity of environmental issues is highlighted in the syllabus and in teachers’ intentionality and practice. The findings also show that a limited variety of teaching methods were used in problem solving strategies. The study also found that problem solving was influenced by different constructivist learning principles. The study further found that limited numbers of problem-solving steps were used in the process of problem solving. The study concludes by calling for further research into problem solving strategies. This can be done to empower Geography teachers to use more complex problem solving strategies to deepen problem solving and to engage problems in more depth.
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Neurocognitive effects of head and body collisions on club level rugby union players

  • Authors: Zoccola, Diana
  • Date: 2015
  • Subjects: Head -- Wounds and injuries -- Psychology , Neuropsychological tests , Head -- Wounds and injuries , Sports injuries -- Psychological aspects
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3257 , http://hdl.handle.net/10962/d1016397
  • Description: The objective of the study was to investigate the cumulative neurocognitive effects of repetitive concussive and subconcussive events in club level Rugby Union (hereafter rugby) during the course of one rugby season, in a combined group and individualized case-based approach. Amateur adult club level rugby players (n = 20) were compared with a non-contact control group (n = 22) of equivalent age, years of education and estimated IQ (p = > .05, in all instances), although the two groups were clearly differentiated on the basis of a history of reported concussions (p = < .05). Video analyses documented the tackling maneuvers observed amongst the players during all matches across the rugby season revealing a sobering average of more than a thousand tackles per player, excluding any contact practice sessions. Five rugby players (n = 5) who were observed to have a head jarring event were also isolated for individualized postconcussive follow-up analysis of their neurocognitive profiles. Measures included the ImPACT Verbal and Visual Memory, Visual Motor Speed and Reaction Time composites and the Purdue Pegboard. Independent and dependent statistical analyses were employed to compare the rugby versus control group neurocognitive test profiles at and between the three test intervals. Correlational analyses explored the association between concussion, tackling and neurocognitive test outcomes. Descriptive comparisons of individual neurocognitive test scores with normative data were employed for the case analyses. Taken together, the results implicated vulnerability amongst club rugby players on the motor and speeded tasks, with less robust indications on the memory tasks. While limited in terms of its small sample size, it is considered that the outcome of the study was rendered more robust by virtue of being methodologically multifaceted with heuristic implications for future research studies in the area. The novel inclusion of tackling data as well as fine-tuned case analyses, were of particular relevance in that regard. The results add to a growing body of literature that implicates deleterious neurocognitive effects in participants of a sport such as rugby due to repetitive head jarring incidents that are intrinsic to the game.
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The spatial planning of racial residential segregation in King William's Town : 1826-1991

  • Authors: Zituta, Heyman Mandlakayise
  • Date: 1997
  • Subjects: Apartheid -- South Africa -- King William's Town , City planning -- South Africa -- King William's Town , King William's Town (South Africa) -- History
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:4855 , http://hdl.handle.net/10962/d1005531 , Apartheid -- South Africa -- King William's Town , City planning -- South Africa -- King William's Town , King William's Town (South Africa) -- History
  • Description: This study investigates the spatial planning of racial residential segregation in King William's Town, induding its former homeland township of Zwelitsha, from 1826 to 1991. The first settlement in the 'white' King William's Town, Brownlee Mission Station, was established in 1826.The town of King William's Town was developed from this settlement. The racial laws which were applied to segregate blacks nationally and locally came to an end in 1991. Primary sources of information were used to determine whether King William's Town was planned along racial lines and to determine the major role players who formulated and implemented the policy. Key sources were archival material, newspapers, maps, interviews, Deeds Office files and the work of other scholars. The establishment of the towm from its genesis as a mission station and a military base is traced and the effects of this legacy on racial separation is detailed. It was found that racial planning of residential areas in King William's Town had been practised in this small town for a long time (prior to the Group Areas Act). The implementation of this policy was marked by forced removal of blacks from areas which were regarded as being for whites. These predominently African concentrations on the east bank of the Buffalo River were relocated to the west bank which was regarded as a black area.An anomalous incident was discovered in this study namely that these racial removals took place before the central state introduced national policy which compelled all local states to plan their residential areas along ethnic considerations. In parallel with the practice of segregation in King William's Town, the township of Zwelitsha was developed adjacent to the town by the government. As this thesis reveals, the development of Zwelitsha was intimately related to that of King William's Town. The major role players in planning residential areas on racial basis were identified as the municipal Council of King William's Town. They were involved in planning racially segregated areas before and after the Group Areas Act. They (the Council) succeeded in closing all freehold locations in the town (1940) and forced the residents to become their tenants who rented dwellings in the west bank municipal location. There were attempts to incorporate this municipal location into the neighbouring homeland township of Zwelitsha. This move was eventually accomplished when all townships in the vicinity of King William's Town were amalgamated to form King William's Town Transitional Local Council in terms of the Local Government Transition Act of 1994 (Government Gazette No. 15468 of 2nd February 1994).
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An exploration of health professional's perceptions of the role of clinical psychologists

  • Authors: Zitianellis, Marina Sophia
  • Date: 2005
  • Subjects: Community health services -- South Africa , Community mental health services -- South Africa , Medical personnel -- South Africa -- Attitudes , Primary health care -- South Africa , Clinical psychologists
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3091 , http://hdl.handle.net/10962/d1002601 , Community health services -- South Africa , Community mental health services -- South Africa , Medical personnel -- South Africa -- Attitudes , Primary health care -- South Africa , Clinical psychologists
  • Description: The South African government has initiated the transformation of health services in the country towards primary health care (PHC) in order to provide comprehensive care to individuals and families. The move to PHC involves an increased need for collaboration between health professionals. It is proposed that for effective team-work to take place, an understanding of the roles and functions of team members is imperative in providing quality mental health care. This study explored health professionals’ perceptions of the role and function of clinical psychologists working as part of a health care team in a community context. Three focus groups and three individual interviews were conducted with social workers, nurses and doctors. The data was then processed and analysed using a grounded theory method. The research highlighted the importance of knowledge, and how this affects referrals, perceptions, inter-professional relations and the perceived usefulness of clinical psychology and clinical psychologists. What is of significance is the potential power that the health professionals have as gatekeepers between the general public and clinical psychologists.
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Machine learning methods for calibrating radio interferometric data

  • Authors: Zitha, Simphiwe Nhlanhla
  • Date: 2019
  • Subjects: Calibration , Radio astronomy -- Data processing , Radio astronomy -- South Africa , Karoo Array Telescope (South Africa) , Radio telescopes -- South Africa , Common Astronomy Software Application (Computer software)
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/97096 , vital:31398
  • Description: The applications of machine learning have created an opportunity to deal with complex problems currently encountered in radio astronomy data processing. Calibration is one of the most important data processing steps required to produce high dynamic range images. This process involves the determination of calibration parameters, both instrumental and astronomical, to correct the collected data. Typically, astronomers use a package such as Common Astronomy Software Applications (CASA) to compute the gain solutions based on regular observations of a known calibrator source. In this work we present applications of machine learning to first generation calibration (1GC), using the KAT-7 telescope environmental and pointing sensor data recorded during observations. Applying machine learning to 1GC, as opposed to calculating the gain solutions in CASA, has shown evidence of reducing computation, as well as accurately predict the 1GC gain solutions representing the behaviour of the antenna during an observation. These methods are computationally less expensive, however they have not fully learned to generalise in predicting accurate 1GC solutions by looking at environmental and pointing sensors. We call this multi-output regression model ZCal, which is based on random forest, decision trees, extremely randomized trees and K-nearest neighbor algorithms. The prediction error obtained during the testing of our model on testing data is ≈ 0.01 < rmse < 0.09 for gain amplitude per antenna, and 0.2 rad < rmse <0.5 rad for gain phase. This shows that the instrumental parameters used to train our model more strongly correlate with gain amplitude effects than phase.
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