The refinement of protective salinity guidelines for South African freshwater resources
- Authors: Slaughter, Andrew Robert
- Date: 2005
- Subjects: Water salinization -- South Africa Salinization -- Control -- South Africa Salinity -- South Africa Freshwater ecology -- South Africa Water resources development -- South Africa Caridina Caridina -- Effect of pollution
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6031 , http://hdl.handle.net/10962/d1006170
- Description: South Africa is an arid country and its growing population is putting freshwater resources under increasing pressure. Natural salinization of freshwater systems is being exacerbated by anthropogenic influences. The National Water Act (No. 36 of 1998) stipulates the need for an ecological Reserve, that quantity and quality of freshwater needed to protect freshwater ecosystems while allowing sustainable use of freshwater resources. Water guidelines do exist in the form of the South African Water Quality Guidelines (DWAF, 1996) and more recently, Jooste and Rossouw (2002) compiled benchmark values for water quality variables marking the boundaries between ecological health classes in the 4-category classification system. Predominantly international toxicity data were used to compile the guidelines and the benchmark values. In addition, there is a paucity of chronic toxicity data nationally and internationally. This thesis showed that it is statistically possible to derive protective chronic endpoints for salinity from acute toxicity data through extrapolation. The Acute to Chronic Ratio (ACR), Two-Step Linear Regression (LRA) and Multi-Factor Probit Analysis (MPA) extrapolation methods were investigated to derive chronic toxicity data from acute toxicity data. The authors of LRA and MPA recommend associating a time independent LCx value in the range of LC₀¸₀₁ to LC₁₀ with a Predicted No Effect Concentration (PNOEC). In addition to published methods, this thesis studied the possibility of equating a time independent LC₅₀ value and subjected to a safety factor of 5 (LRA LC₅₀/5), to the PNOEC. Extrapolated chronic toxicity data where the toxicants are NaCl and Na₂SO₄ were derived for indigenous South African macroinvertebrates. NaCl and Na₂SO₄ are salts associated with salinisation in South Africa. In addition, a chronic salinity toxicity test protocol for an indigenous South African aquatic macroinvertebrate was designed and chronic toxicity test were performed using NaCl and Na₂SO₄ as toxicants. The experimental chronic toxicity data produced were used to validate results from the acute to chronic extrapolation methods. Extrapolated chronic toxicity data were inputted into Species Sensitivity Distribution curves, and concentrations that were predicted to protect 95 % of species (PC95) were compared to the sub-lethality benchmarks proposed by Jooste and Rossouw (2002) for NaCl and Na₂SO₄. This study concluded that the LRA LC₅₀/5 extrapolation method is the most protective and accurate and proposed that LRA replace the ACR method in future guideline development for inorganic salts.
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The relationship between leadership and internal customer satisfaction within a motor manufacturing company in Gauteng
- Authors: Samuel, Glen
- Date: 2005
- Subjects: Automobile industry and trade -- Employees -- South Africa -- Gauteng Automobile industry and trade -- Customer services -- South Africa -- Gauteng Job satisfaction Customer services -- Management Industrial relations -- South Africa -- Gauteng Employee morale Personnel management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:758 , http://hdl.handle.net/10962/d1003879
- Description: This research investigates the relationship between leadership and internal customer satisfaction, also called employee satisfaction in this document. The research is conducted within an automotive manufacturer situated in the province of Gauteng, South Africa. The Service Profit Chain forms the foundation on which this research is based as it suggests that the various factors within the service delivery system of an organisation ultimately affect the success of an organisation. From the Service Profit Chain, it is established that a factor that affects employee satisfaction is the leadership within the organisation. The Full Range Leadership Development Theory provides the backbone for analysing the leadership style of each manager by using the Multifactor Leadership Questionnaire. The company’s employee satisfaction model provides the theoretical construct against which the employee satisfaction of the managers’ subordinates is measured using the company’s employee satisfaction questionnaire. Information was gathered from the managers who rated their leadership styles as they perceived it; and from their respective subordinates who rated the managers’ leadership style as they perceived it and also their satisfaction as employees as they perceived it. Data obtained from each instrument, for the respective managers, was then statistically analysed. The reliability of the data could not be proved for some of the factors of the 2 research instruments. However, this research found a statistically significant relationship between transformational leadership and some factors of employee satisfaction, albeit a weak relationship. The null hypothesis was rejected and the alternate hypothesis accepted. A statistically significant relationship exists between leadership style and employee satisfaction levels within an automotive manufacturing organisation.
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The role of a principal in an academically successful farm school: a case study
- Authors: Nongauza, Anthony Davidson Mbulelo
- Date: 2005
- Subjects: School principals -- South Africa -- Case studies School management and organization -- South Africa -- Case studies Rural schools -- South Africa -- Case studies Education, Rural -- South Africa -- Case studies School supervision, Rural -- South Africa -- Case studies Rural schools -- South Africa -- Administration of -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1747 , http://hdl.handle.net/10962/d1003631
- Description: This study looks at the various actions by the principal of a farm school in running an academically successful school. The study exposes the difficulties faced by farm schools and looks at how the principal confronts these difficulties and turn some of these into success stories. In trying to understand the role of the principal this study uses school effectiveness literature as a source and reference in an attempt to understand the actions adopted by the principal to make this farm school successful. The study uses the interpretive orientation as the methodology for investigating the principal’s role. This is in line with my attempt at explaining the perceptions, views and experiences of the people who are working closely with the principal. I have done this by employing semi-structured interviews and participant observation. The information gathered from the respondents helped in the development of the role of the principal which in this case, is the expressed views of the respondents. The investigation is conducted as a case study and the handling of the information provided by the respondents is in line with case study methods. The study has revealed that actions of the leader have an influence on the organizational success. The way in which the leader of Rocklands farm School conducts herself and the vision she shares with the people within the organization go a long way towards the improvement of organizational structures and their functioning. In this case the principal has been noted as particularly transformational, charismatic, instructional and transactional in her approaches to school administration and that her dedication to the cause of learners from disadvantaged background is reflected in her sacrificial actions. The study has also found that the principal is considered to be fairly autocratic in her leadership, which is a departure from current leadership thinking. The study has also shown that socio-economic disadvantages do not necessarily inhibit the school from performing beyond expectation. With good guidance from the leader and trust among staff members the farm school has been able to overcome some socio-economic pressures to emerge successful in the academic field. The fact that the principal of this school is a woman has not changed the overall findings that leadership qualities for successful schooling are universal and do not necessarily depend on the gender of the leader. This study suggests that leaders have a potential to turn poor situations in schools around and that leaders should as a matter of course ensure that they understand the organizational dynamics within their schools. They should be in the forefront as agents of change being mindful that those within the school understand and share the vision the leader has. The study also suggests that the human element in the educational processes in schools is of critical importance than the conditions in which schools find themselves.
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The role of acute toxicity data for South African freshwater macroinvertebrates in the derivation of water quality guidelines for salinity
- Authors: Browne, Samantha
- Date: 2005
- Subjects: Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4742 , http://hdl.handle.net/10962/d1006173 , Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Description: Water resources are under ever-increasing pressure to meet the demands of various water users both nationally and internationally. The process of anthropogenically-induced salinisation serves to exacerbate this pressure by limiting the quantity and quality of water available for future use. Water quality guidelines provide the numerical goals which water resource managers can use to adequately manage and protect aquatic ecosystems. Various methods which have been developed and used internationally to derive such guidelines are discussed. Acute toxicity tests were conducted using two inorganic salts, NaCl and Na₂SO₄. Field collected, indigenous, freshwater macroinvertebrates were used as tests organisms. Data generated from these tests contributed to the expansion of the currently limited toxicological database of response data for indigenous organisms and the suitability of using such organisms for future testing was discussed. Salt sensitivities of indigenous freshwater invertebrates were compared those of species sourced from an international toxicological database and were found to have similar ranges of tolerances to NaCl and Na₂SO₄. Species sensitivity distributions (SSDs), a method of data extrapolation, were derived using different types of toxicological data, and hence different guideline values or protective concentrations were derived. These concentrations were equated to boundary values for South Africa’s ecological Reserve categories, which are used to describe degrees of health for aquatic ecosystems. Provisional results suggest that using only acute toxicity data in guideline derivation provides ecosystem protection that is under-protective. Chronic toxicity data, which include endpoints other than mortality, provide the most realistic environmental protection but lack data confidence due to small sample sizes (acute tests are more readily conducted than chronic tests). The potential contribution of sub-chronic data to guideline derivation is highlighted as these data are more readily extrapolated to chronic endpoints than acute data and sub-chronic tests are not as complex and demanding to conduct as chronic tests.
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The role of anthropogenic disturbance in the creation of a socio-ecological landscape
- Authors: Fox, Helen Elizabeth
- Date: 2005
- Subjects: Human ecology -- South Africa -- Kat River Valley , Land use -- Environmental aspects-- South Africa -- Kat River Valley , Landscapes -- Social aspects -- South Africa -- Kat River Valley , Landscape ecology -- South Africa -- Kat River Valley , Vegetation and climate -- South Africa -- Kat River Valley , Xhosa (African people) -- Folklore , Kat River Valley (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4772 , http://hdl.handle.net/10962/d1008061 , Human ecology -- South Africa -- Kat River Valley , Land use -- Environmental aspects-- South Africa -- Kat River Valley , Landscapes -- Social aspects -- South Africa -- Kat River Valley , Landscape ecology -- South Africa -- Kat River Valley , Vegetation and climate -- South Africa -- Kat River Valley , Xhosa (African people) -- Folklore , Kat River Valley (South Africa)
- Description: The aim of this thesis is to examine the role of anthropogenic disturbance in the creation of a socio-ecological landscape. Three key questions were answered: what impact has past anthropogenic disturbance had on present vegetative characteristics; what value did this disturbed landscape have to local people; how did the local peoples' worldviews and eco-cosmologies influence how they perceived, valued and managed their landscape? Research was based in a rural, predominantly amaXhosa village in the Kat River valley, Eastern Cape, South Africa. Four major landscape components characterised the environment, namely dense forests, former grazing lands, abandoned fields and old settlements. A combination of qualitative and quantitative methods were adopted, consisting of a vegetation and soil survey and social science methods including semistructured interviews, focus groups, transect walks and participant observation. The key finding was that anthropogenic disturbance is necessary to enhance the potential of the area to support human habitation. However, anthropogenic disturbance can have positive or negative effects for both local people and the environment. An intermediate level of disturbance is a key factor leading to a resilient socio-ecological system. Various anthropogenic disturbances have had significant affects on vegetation characteristics in terms of species richness, and a change in vegetation composition and species heights. Of the three anthropogenic landscapes examined, former grazing lands were the least intensively disturbed. They were also more species rich and structurally diverse than areas that were under agricultural production or used as a settlement. Dense forests, although the least desirable landscape to local people were, together with sacred pools, sources of ecosystem renewal and played a critical role during times of disturbance. Anthropogenic disturbance has added value to local people's livelihoods; this disturbance has resulted in a patchy landscape that supplies a wide variety of resources to local people. Local people are dependent on their environment for their basic needs; this has encouraged sustainable management practices. The local AmaXhosa still retain many elements of their traditional worldview, which has many characteristics of Animism. The environment is an integral component of their belief system and certain sites and species have significant cultural value and are protected.
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The role of communication in the management and leadership of a secondary school in Namibia
- Authors: Kaura, Unjee M
- Date: 2005
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1862 , http://hdl.handle.net/10962/d1004559
- Description: Communication is a complex phenomenon, widely regarded as the lifeblood of every organisation, and ironically one of the least researched areas, at least in the field of leadership and management in an educational context. The paucity of literature in this field is evidence of this. This study is an attempt to explore and gain understanding of teachers' experiences and perceptions of the role and functions of communication within an educational organisation, in this case a secondary school in Namibia. The study is an interpretive case study, and employed questionnaires and interviews to gather data from selected participants at the site of research. The findings of the study highlight the dual role of communication as a functioning mechanism as well as a social or binding factor. The role of communication emerges as an essential element in the democratic functioning of the school. It is through communication that democratic practice is achieved as a vehicle for involvement in decision-making, sharing, teamwork, and as a medium for leadership leading to empowerment, human development and organisational development, bringing about change through the sharing of vision. Both formal and informal communication are shown to be functional to the institution. Some of the challenges that have emerged are the dangers of careless and malicious 'badmouthing' in informal communication, the persistence of some degree of top-down communication, and the challenges of communication in multi-cultural settings. The study highlights the need for strategies to improve communication, such as workshops on interpersonal communication.
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The role of parallel computing in bioinformatics
- Authors: Akhurst, Timothy John
- Date: 2005
- Subjects: Bioinformatics , Parallel programming (Computer science) , LINDA (Computer system) , Java (Computer program language) , Parallel processing (Electronic computers) , Genomics -- Data processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3986 , http://hdl.handle.net/10962/d1004045 , Bioinformatics , Parallel programming (Computer science) , LINDA (Computer system) , Java (Computer program language) , Parallel processing (Electronic computers) , Genomics -- Data processing
- Description: The need to intelligibly capture, manage and analyse the ever-increasing amount of publicly available genomic data is one of the challenges facing bioinformaticians today. Such analyses are in fact impractical using uniprocessor machines, which has led to an increasing reliance on clusters of commodity-priced computers. An existing network of cheap, commodity PCs was utilised as a single computational resource for parallel computing. The performance of the cluster was investigated using a whole genome-scanning program written in the Java programming language. The TSpaces framework, based on the Linda parallel programming model, was used to parallelise the application. Maximum speedup was achieved at between 30 and 50 processors, depending on the size of the genome being scanned. Together with this, the associated significant reductions in wall-clock time suggest that both parallel computing and Java have a significant role to play in the field of bioinformatics.
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The rural-urban interface: the ambiguous nature of informal settlements, with special reference to the Daggafontein settlement in Gauteng
- Authors: Kumalo, Sibongiseni
- Date: 2005
- Subjects: Cities and towns -- South Africa -- Gauteng -- Growth , Squatter settlements -- South Africa -- Gauteng , Urban anthropology -- South Africa -- Gauteng , Rural-urban migration -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2091 , http://hdl.handle.net/10962/d1002654 , Cities and towns -- South Africa -- Gauteng -- Growth , Squatter settlements -- South Africa -- Gauteng , Urban anthropology -- South Africa -- Gauteng , Rural-urban migration -- South Africa
- Description: The thesis is concerned with the rural-urban interface. It questions and argues against the validity of what used to be called the rural-urban divide, and presents the rural-urban interface as a single social field. The research makes use of Daggafontein informal settlement in Gauteng, providing a general socio-economic overview of this settlement by discussing the ways in which people in this settlement make a living. Most of the people come from rural areas and the patterns of their association within the settlement reveal that they associate themselves with people from their own rural homes of origin. Movement between Daggafontein and rural areas show some level of commitment to home areas. Perceptions of the urban-rural interface by people of Daggafontein informal settlement show that these two areas are not necessarily separate from each other, but are part of the same continuum as socio-economic relations continue to straddle the rural and the urban. As people, perceptions and values move in both directions along the rural-urban interface, the classification of the informal settlement becomes highly ambiguous, because it contains both rural and urban elements.
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The safety of journalists: an assessment of perceptions of the origins and implementation of policy at two international television news agencies
- Authors: Venter, Sahm
- Date: 2005
- Subjects: Reuters Television , Associated Press Television News , Journalism -- Safety measures , Journalists -- Protection , News agencies -- Safety measures
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3491 , http://hdl.handle.net/10962/d1002946 , Reuters Television , Associated Press Television News , Journalism -- Safety measures , Journalists -- Protection , News agencies -- Safety measures
- Description: Being a journalist today can be a deadly pursuit, particularly for those covering conflict and other dangerous assignments. In 2004 more journalists and other media workers were killed than in the last ten years. While it is impossible to guarantee that journalists will not be killed or injured, kidnapped or detained, a policy has been created to help protect them in the course of their duties. This study examines the perceptions of journalists working for two international television news agencies about this safety policy called the ‘Joint code of practice for journalists working in conflict zones’. This policy was adopted in November 2000 by five major television companies including the television news agencies Reuters Television and Associated Press Television News. This study finds that the policy had significant flaws in how it was formulated and how it is communicated, implemented and reviewed. Recognising the existence of unequal relations of power and conflicting interests at play in any policy process, this study stresses that in the case of the journalist safety policy, all stakeholders should have participated in the relevant policy stages. This argument arises from researching the policy document as well as from the point of view of managers, and particularly journalists who work on dangerous assignments, either full-time or on a freelance basis for either of the two television news agencies. It finds that while journalists are not generally aware of the policy, they do practice many of its elements as well as a range of their own custom-made strategies to protect themselves. The result is to make the policy less effective than it could be.
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The status and natural history of pygmy (Kogia breviceps) and dwarf (K. sima) sperm whales off Southern Africa
- Authors: Plön, Stephanie
- Date: 2005
- Subjects: Pygmy sperm whale Dwarf sperm whale Population genetics
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5772 , http://hdl.handle.net/10962/d1005460
- Description: For the present study 106 strandings of Kogia breviceps and 85 strandings of K. sima along the South African coastline between 1880 and 1995 were analysed in order to examine the age and growth, male and female reproduction, diet, stranding patterns, and population genetic structure of both species. Length and weight at birth were about 120cm and 53kg for K. breviceps and about 103cm and 14kg for K. sima. Von Bertalanffy growth curves were fitted to the data and indicated that physical maturity was reached at around 15 years in both sexes of K. breviceps and at 13 years in female and 15 years in male K. sima. Asymptotic length was reached at 306.0 and 286.1cm in female and male K. breviceps and 249.14 and 263.75cm in female and male K. sima, respectively. Maximum ages were16 years for male K. breviceps and 23 years for females and 17 years for male K. sima and 22 years for females. Reversed sexual size dimorphism was suggested for K. breviceps, while in K. sima males were larger than females. Attainment of sexual maturity in males occurred at between 2.5 and 5 years of age in K. breviceps and 2.6 and 3 years in K. sima, corresponding to 241-242cm and 197cm body length, respectively. The maximum combined testis weight comprised 1.04% and 2.00% for K. breviceps and K. sima, respectively, and a polygynous mating system with a roving male strategy was proposed for both species. The sperm morphology for both Kogia species was described and is characterised by 20-25 spherical mitochondria arranged in rows around the midpiece. Attainment of sexual maturity in females occurred at 5 years in both Kogia species, and at 262cm and 215cm body length in K. breviceps and K. sima, respectively. The ovulation rates were 0.9 and 0.7 per year for K. breviceps and K. sima, respectively. In K. breviceps conceptions occurred from April to September and births from March to August, while in K. sima both conceptions and births occurred from December to March. Annual reproduction and a post-partum oestrus was suggested for both Kogia species. The diet of K. breviceps comprised 50 different cephalopod species from 22 families and 17 other prey species, while K. sima fed on 32 cephalopod species from 17 families and six others. Although niche overlap indices between the two species and between groups within each species were high, some differences in diet could be determined, which allow these two sympatrically occurring species to share the same ecological niche off the coast of Southern Africa. An analysis of the stranding patterns revealed that K. sima has a closer affinity to the Agulhas current and to higher water temperatures than K. breviceps, which is supported by differences in the size of the appendages between the two species. The population genetic analysis revealed a high haplotype and nucleotide diversity for K. breviceps in the Southern hemisphere, but a lack of significant phylogeographic structure, indicating substantial gene flow among populations and inhibiting genetic differentiation of local populations, although the South African population was somewhat isolated from others in the Southern Hemisphere. In contrast the data on the phylogeographic structure of K. sima were somewhat restrictive as the majority of the samples originated from South Africa. Nevertheless, both nucleotide and haplotype diversities were markedly lower than in K. breviceps and more similar to those for other small cetacean populations, suggesting a smaller population size for K. sima than for K. breviceps. Although both Kogia species belong to the medium to larger-sized odontocetes their life histories are located near the fast end of the slow-fast continuum of life histories of marine mammals, indicating high mortality rates. The “false-gill” marking and the ability to squirt ink are thought to reflect adaptations to predator mimicry and avoidance.
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The therapist as a "bad object": the use of countertransference enactment to facilitate communication in therapy
- Authors: Webster, Penny
- Date: 2005
- Subjects: Countertransference (Psychology) Countertransference (Psychology) -- Therapeutic use Communication -- Psychological aspects Psychotherapist and patient Psychoanalysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3083 , http://hdl.handle.net/10962/d1002592
- Description: Psychoanalysis as it exists today is not constituted by a single theoretical framework describing pathology and indicating a specific set of interventions. Since Freud originally conceptualised psychoanalytic understanding of pathology and psychoanalysis as a mode of intervention, there have been many revisions and reformulations of his theory. This thesis has attempted to integrate some psychoanalytic ideas regarding personality formation, psychopathology and psychotherapeutic intervention (Fairbairn, 1952; Ogden, 1992, 1994), with interpersonal (strategic / structural) ideas regarding intervention (Minuchin, 1974; Sullivan, 1940, 1953, 1964). In order to do so, the thesis used the relational psychoanalytic perspective, as depicted by Aron (1996) and Mitchell and Aron (1999), as an overarching conceptual framework. The focus from these points of view is the patient's internalized relationship patterns and the therapist's participation in their repetition. It is held that internalized relationship patterns are not only based on, but can be changed by, lived experience. From this perspective, the goal of therapy is to enhance the patient's capacity to reflect and think about experience, and therefore, to communicate about it. This means a change in the patient's predominant mode of communication. Ogden's (1994) modes of communication were described. The thesis suggested that Ogden's modes of communication can be stretched or translated into the types of communication outlined by Langs (1978). This thesis aimed to explore the deliberate use of countertransference responses to facilitate communication in the beginning stages of therapy with patients functioning predominantly in the paranoid-schizoid mode (Ogden, 1992). Patients who operate in this mode are often unable to tolerate interpretation and therefore traditional approaches to intervention are not effective. A "strategic / structural relational psychoanalytic" approach to treatment was proposed. It was suggested that therapists utilize joining and accommodation techniques as described by Minuchin (1974) and alter their style of interaction to match that of the various object relational constellations that they have managed to identify within the patient via their countertransference responses. It was hypothesized that patients need their therapists to be similar to their original objects in order to feel safe in the therapeutic environment and that this may facilitate communication in the beginning stages of therapy. The research utilized a qualitative research approach. Qualitative research methods attempt to use data gathered phenomenologically, always acknowledging the researcher's biases when gathering the data. The data gathered is then interpreted according to various theories or hermeneutic lenses. The hypothesis mentioned above has been investigated by analyzing three cases in terms of the research questions based on Langs' (1978) classification of communication. The thesis described the difficulties inherent in collecting clinical data from psychologists working from within a psychoanalytic framework. Eventually three sets of therapy details and verbatim therapy transcripts were obtained, provided in the thesis and analyzed in terms of the research questions. However evidence for the success of the hypothesized alternate approach was not found in this research study. It was suggested that other possible methods might be useful to investigate the hypothesized approach further.
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The use of Van Hiele's theory to explore problems encountered in circle geometry: a grade 11 case study
- Authors: Siyepu, Sibawu Witness
- Date: 2005
- Subjects: Geometry -- Study and teaching (Secondary) -- South Africa Mathematics -- Study and teaching (Secondary) -- South Africa Mathematics teachers -- Training of -- South Africa Mathematical ability -- Testing
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1871 , http://hdl.handle.net/10962/d1004777
- Description: The research presented in this thesis is a case study located in the interpretive paradigm of qualitative research. The focus is on the use of van Hiele's theory to explore problems encountered in circle geometry by grade 11 learners and making some policy recommendations concerning the curriculum structure and teaching of the geometry at all grades. The interpretation is based to the learners' background in geometry i.e. their prior knowledge and experience of learning geometry. The study was carried out over a period of three years. The data collection process took a period of two months (April and May 2003) with a group of 21 grade 11 mathematics learners in a rural senior secondary school in the Eastern Cape. The researcher used document analysis, worksheets, participants' observation, van Hiele tests, a questionnaire and semi-structured interviews to collect data. The study showed that the structure of the South African geometry syllabus consists of a some what disorganized mixture of concepts. It is not sequential and hierarchical and it sequences concepts in a seemingly unrelated manner. The study revealed that the South African high school geometry curriculum is presented at a higher van Hiele level than what the learners can attain. The findings of the study showed that many of the grade 11 learners were under-prepared for the study of more sophisticated geometry concepts and proofs. Three categories of reasons could be ascribed to this: Firstly, there was insufficient preparation of learners during the primary and senior phases. Secondly the study indicated that there is overload of geometry at the high school level in the South African mathematics curriculum. Thirdly, the over-reliance on the traditional approach to teaching geometry, poor presentation of mathematical technical concepts and language problems, were identified as possible additional reasons for the poor learner understanding of geometry in general and circle geometry in particular. The study recommends that the structure of the South African geometry curriculum should be revisited and redesigned. Teachers should be empowered and developed to be more effective in teaching geometry through further studies in mathematics and in-service workshops. They should also be engaged in the process of implementing the van Hiele's theory in the teaching of geometry in their classrooms.
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Three perspectives on ukuthwasa: the view from traditional beliefs, western psychiatry and transpersonal psychology
- Authors: Booi, Beauty Ntombizanele
- Date: 2005
- Subjects: Healers -- South Africa , Divination -- South Africa , Schizophrenia -- Social aspects , Xhosa (African people) -- Psychology , Xhosa (African people) -- Social life and customs
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2936 , http://hdl.handle.net/10962/d1002445 , Healers -- South Africa , Divination -- South Africa , Schizophrenia -- Social aspects , Xhosa (African people) -- Psychology , Xhosa (African people) -- Social life and customs
- Description: Among the Xhosas, the healing sickness called intwaso is interptreted as a call by the ancestors to become a healer. Transpersonalists also see these initiatory illnesses as spiritual crises, while according to the widely accepted Western psychiatric view, illness is purely perceived in physical and psychological terms. A case study was conducted where a single participant who has undergone the process of ukuthwasa and is functioning as a traditional healer was interviewed. A series of interviews were done where information was gathered about significant experiences related to ukuthwasa process. Tapes were transcribed and a case narrative was written and interpreted using the traditional Xhosa beliefs, the western psychiatric and the transpersonal psychology perspectives. Strengths and weaknesses of each perspective were then examined.
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Towards the development of a protocol for rearing juvenile rock lobster, Jasus lalandii
- Authors: Esterhuizen, J. A
- Date: 2005
- Subjects: Lobsters -- Growth , Lobster fisheries -- South Africa , Crustacea -- Growth , Crustacea -- South Africa , Jasus lalandii , Lobster culture
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5328 , http://hdl.handle.net/10962/d1005174 , Lobsters -- Growth , Lobster fisheries -- South Africa , Crustacea -- Growth , Crustacea -- South Africa , Jasus lalandii , Lobster culture
- Description: The diversification of current aquaculture practise in South Africa is crucial for the future development of the industry. The rock lobster, Jasus lalandii has been identified as a possible candidate species for shore based culture in systems similar to those used for abalone farming. Reduced Total Allowable Catch (TAC's) and an increased minimum legal size were implemented as management strategies to relieve fishing pressure on natural stocks of J. lalandii, and in turn led to increased market demand and a possible niche for farmed lobsters. High puerulus settlement along the Namibian coast, together with other favourable aquaculture attributes, indicate that the commercial grow out of wild harvested juveniles could be feasible. The aim of study was to investigate the feasibility of growing out rock lobsters in shore based systems in Namibia and South Africa. The experimental objectives of the project were to investigate the nutritional requirements, as well as the effect of stocking density and tank design on growth and survival of J. lalandii. The economic viability of shore based rock lobster farming was then evaluated based on the experimental results and typical capital requirements of an abalone farm in South Africa. Puerulus and early juvenile rock lobsters were collected in Luderitz, Namibia and transported to HIK Abalone Farm in Hermanus, South Africa where they were acclimated in black fibre glass tanks in a flow through system. The pueruli were stocked at 50, 75, 100 and 125/m² and early juveniles at 20, 30, 40 and 50/m² to test the effect of density on growth and survival. A comparative dietary study with both size classes was conducted using a mussel diet (Choromytilus meridionalis and Mytilus galloprovincialis), a commercial shrimp feed diet and a rotational diet comprising both mussels and shrimp feed. Tanks provided with "v-shaped" asbestos hides, PVC hides and no hides were compared to test the effect on growth rate and survival of pueruli. All treatments were conducted in triplicate. Temperatures were recorded twice daily while water quality parameters were tested every second week. The results indicate that density had a significant effect on growth and survival on post-pueruli. An initial stocking density of 75 post-pueruli/m² is regarded as optimal both in terms of the growth rate and biomass production per tank. No differences in growth and survival rates were attained in the early juvenile size class. This indicates that higher densities can be used to rear juvenile J. lalandii. No significant differences were obtained in growth rate when reared under different hide conditions although asbestos hides yielded significantly higher survival rates (93.3 %) compared to the tanks provided with PVC hides (74.04 %) and no hides (77.8 %, p≤0.05). As a result of the high survival rate observed in tanks provided with "V-shaped" asbestos hides, these tanks also yielded higher biomass production per tank (297.8 grams) compared to the tanks provided with PVC hides and no hides (261.09 and 260.5 grams respectively). In the diet trials, growth rates of post pueruli and juvenile lobsters fed the mussel and rotational (mussel and shrimp feed) diets did not differ significantly, however, growth rates of lobsters fed the shrimp feed only diet was significantly lower than both the mussel and rotational diets (p≤0.05). Lobsters fed the mussel diet yielded significantly higher survival rates compared to lobsters fed either the rotational diet or shrimp feed diet only. An imbalance in the fatty acid profile of the shrimp feed could have been a major contributing factor to the poor growth and survival in lobsters fed the shrimp feed only diet as the level of linoleic acid (LOA) was exceptionally high resulting in a high (n -6):(n-3) ratio (1.01) compared to the mussel and rotational diets (0.17 and 0.56 respectively). The low level of arachidonic acid (ARA) in the shrimp feed diet could be a further contributing factor explaning for the poor growth and survival of juvenile rock lobsters. An economic feasibility study was conducted at the end of the experimental phase by modelling a hypothetical shore based rock lobster farm. A projection of production costs and revenues was based on the typical costs of a shore based abalone farm and the current market prices for wild harvested J. lalandii. The economic viability was evaluated using benefit-cost ratios, payback period, internal rate of return and breakeven analysis. Sensitivity analyses revealed that the projected lobster growth and survival rates were the main biological factors influencing the economic feasibility of the hypothetical rock lobster farm. An assumed four year grow out period at a low stocking density yielded more lucrative internal rate of return (IRR), benefit-cost ratio, payback period and net present values (NPV) than a five year grow out period at a high density. The four year grow out scenario proved to be more robust to the fluctuating Rand/US$ exchange rate and could accommodate a lower lobster survival rate. Results presented in this study indicate that rock lobster farming is a marginal commercial prospect based on current production performance and costs. Further research to develop effective puerulus collection techniques as well as to make lobster grow out technology more cost effective is required.
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Towards the development of a protocol for the selection of probiotics in marine fish larviculture
- Authors: Vine, Niall Gordon
- Date: 2005
- Subjects: Marine fishes -- Larvae Bacteria Fishes -- Microbiology Fish culture
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5329 , http://hdl.handle.net/10962/d1005175
- Description: Manipulation or control of the microbiological aquaculture environment has been identified as an important focus area for future hatchery development. Subsequently, alternatives to obtain control of the microbiological environment are being sought of which the field of probiotics appears highly promising. Probiotics are usually selected based on various in vitro characteristics, however, the methods used differ and are sometimes unsuccessful due to poor experimentation. The aim of this work is to contribute towards the development of a protocol for the in vitro screening of bacterial candidate probiotics for marine fish larviculture. To reduce the number of candidate probiotics to be tested in vivo, various in vitro experiments need to be conducted, each screening for a particular mode of action – antagonism towards pathogen through production of antimicrobial compounds, growth and attachment to fish intestinal mucus, and the production of other beneficial compounds such as vitamins, fatty-acids and digestive enzymes. A total of 108 bacteria species were isolated from the digestive tract of the adult common clownfish, Amphiprion percula to screen for potential probiotics to be used in clownfish larval rearing. The antagonistic compounds assay identified twelve isolates which showed antagonism towards two or more aquatic pathogens. This was followed by an in vitro test that involved growing the organisms in fish intestinal mucus and modeling their growth parameters. A ranking index (RI) was developed using the lag period (λ) and doubling time (td) of the organism, where (1over λ x td) x 100. Five candidate probionts (AP1-AP5) with varied growth parameters were used for further in vitro experiments. The attachment to mucus assay introduced a novel tool for quantifying competition for attachment sites between candidate probionts and pathogens on mucus. Candidate probiont Pseudoalteromonas AP5 reduced the attachment ability of Vibrio alginolyticus when added before the pathogen and partially out-competed the pathogen for attachment sites when added second. In vitro screening for the production of beneficial compounds tested the candidate probiotics’ ability to produce digestive enzymes - trypsin, lipase and alkaline phosphatase as well as carotenoids and vitamin C. Candidate probiont Pseudoalteromonas AP5 produced high levels of the enzymes (98.2, 34.1 and 91.3 mU product liberated.ml⁻¹, respectively) and contained carotenoids while Kocuria AP4 contained carotenoids but produced low quantities of enzymes (7.8, 0 and 59 mU product liberated.ml⁻¹, respectively). None of the candidate probiotics produced vitamin C. To eliminate potential pathogenic or toxic candidate probionts, Artemia nauplii were exposed to each candidate probiont and the percentage Artemia mortality after 24-hours was determined. Candidate probiont AP2 caused high mortality of Artemia nauplii (98.4%) and was excluded from further studies. Identification of candidate probionts AP3-AP5 was performed using 16S-rDNA molecular techniques and the bacteria were assigned the names Bacillus AP3, Kocuria AP4 and Pseudoalteromonas AP5, respectively. Two methods of larval probiont delivery were tested – attachment to Artemia, and in-water delivery. Attachment to Artemia was high for both Kocuria AP4 and Pseudoalteromonas AP5 (7.2 x10³ and 2.7x10⁴ bacteria.nauplius⁻¹, respectively) while the in-water viability experiment showed that Kocuria AP4 comprised 23.9% of the total culturable water microflora after 24 hours while Pseudoalteromonas AP5 contributed 100%. To validate the findings from the in vitro experiments, in vivo trials using clownfish larvae were performed. Of the four candidate probiotics tested, only Kocuria AP4 showed potential to increase larval survival. In vitro tests produced a better understanding of the possible mode of action and strategies of competition between bacteria, however, the number of criteria in which a candidate probiont is successful in vitro may not be the best predictor for its effectiveness in vivo. Commercial studies that reduce between-treatment variation are required to test predictions about the most suitable probiont or combinations thereof.
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Training needs for municipal employees: a case study of Makana Municipality
- Authors: Hamaamba, Tyson
- Date: 2005
- Subjects: Municipal officials and employees -- Training of -- South Africa -- Grahamstown Environmental education -- South Africa -- Grahamstown Local officials and employees -- Training of -- South Africa -- Grahamstown Municipal water supply -- South Africa -- Grahamstown Sanitation -- South Africa -- Grahamstown Environmental health -- South Africa -- Grahamstown Environmental management -- South Africa -- Grahamstown Livestock -- Management -- South Africa -- Grahamstown Refuse and refuse disposal -- South Africa -- Grahamstown Fire departments -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1943 , http://hdl.handle.net/10962/d1007952
- Description: This study investigated the education and training needs for municipal employees in order to inform an education and training strategy that would address environmental management challenges in Makana local municipality in Grahamstown, Eastern Cape province. The research was conducted as a qualitative case study that made use of questionnaires, document analysis, focus group discussions and interviews as instruments for data generation. Samples of respondents were selected from Makana Municipality employees in top and middle management positions, professionals/technicians and workers, including elected councillors. The study was contextualised through establishing environmental management issues in Makana municipality; establishing organisational needs; development of a learner profile; and through a review of policies and recent trends in adult education. The study established that the Makana Municipality employees are most concerned with the following issues: sanitation; solid waste management; livestock management and fire management. These issues require primary environmental competences among all council employees (top and middle management, professionals and technicians, workers and councillors who work on part-time basis). The educational implications needed to respond to these issues also require an understanding of legislation. The study also established that technical education and training which includes planning, project management, and financial and budgeting competences are necessary amongst the management and professionals. These competences may enable them to develop capacity in environmental management. This study further established the need for social education which includes competences such as communication and social justice. These competences should be developed amongst members of the same group as they need to involve the community in management of the environment. This should enable the municipality to create job opportunities and help change negative attitudes.
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Understanding editorial independence and public accountability issues in public broadcasting service: a study of the editorial policies at the South African Broadcasting Corporation (SABC)
- Authors: Jjuuko, Denis Charles
- Date: 2005
- Subjects: South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3437 , http://hdl.handle.net/10962/d1002891 , South African Broadcasting Corporation , South African Broadcasting Corporation -- Law and legislation , Broadcasting -- Social aspects -- South Africa , Mass media -- Social aspects -- South Africa , Broadcasting policy -- South Africa
- Description: The concepts of editorial independence and public accountability are necessary in public broadcasting service as they help make a distinction between a public service broadcaster, a government and a commercial service broadcaster. This is because public service broadcasters are tasked with the responsibility of serving the interests of the general public. To do this, the above mentioned concepts have to be in place. This study examines these issues (editorial independence and public accountability) with reference to a case study of the editorial policies of the South African Broadcasting Corporation (SABC). Using public broadcasting theory, policy theory and qualitative research methods, the study examines the genesis of these editorial policies in 2003/2004 and how they provide the SABC with a means of balancing the tensions of editorial independence and public accountability. In analysing the SABC’s editorial policies, the study deals only with those policies whose principles are directly related to editorial independence and public accountability. Although some of these policies are found to be in line with public broadcasting service trends, others are found lacking. Various recommendations are made. The case study demonstrates the importance of an integrated and elaborated policy perspective in setting out how a public service broadcaster can manage editorial independence and public accountability. It also highlights the importance of using international ‘role models’ in ways that are appropriately adapted for the specific country concerned.
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Using aspects of game theory for enhanced stakeholder participation perspectives in integrated water resource management: a Kat River Valley case study
- Authors: Mbatha, Cyril
- Date: 2005
- Subjects: Water resources development -- Case studies , Water-supply -- South Africa -- Kat River Valley -- Management , Economic development -- Case studies , Water-supply -- Government policy -- South Africa , Economic development -- South Africa -- Kat River Valley , Game theory
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:971 , http://hdl.handle.net/10962/d1002705 , Water resources development -- Case studies , Water-supply -- South Africa -- Kat River Valley -- Management , Economic development -- Case studies , Water-supply -- Government policy -- South Africa , Economic development -- South Africa -- Kat River Valley , Game theory
- Description: South Africa is a water poor region and yet, like in many other developing countries, water resources are a valuable production input in socially important industries such as agriculture and mining (Nieuwoudt et al., 2004:162-182). With a mean annual rainfall and runoff of 502mm and 42mm (420m³ per hectare per annum) respectively, Briers and Powell (1993:1) speculate that water shortages will limit South Africa’s economic development in the twenty-first century. In response to the challenges of water resource scarcity and socio-economic inequalities, in 1997 the South African Department of Water Affairs and Forestry (DWAF), following international trends, formulated a National Water Policy (NWP) based on Integrated Water Resource Management (IWRM) principles (Palmer et al., 2003). The main objectives of the NWP (1997) are to protect national water resources from degradation, provide economically disadvantaged communities with access to water resources and promote economic development, through the devolution of water management responsibilities to locally established water institutions (NWP, 1997). The pursuit of these objectives requires a thorough investigation of biophysical, sociopolitical and economic characteristics of the demarcated water areas. For such an investigation to provide accurate and locally relevant results, broad stakeholder participation is of paramount importance. The thesis discusses economic measures required in pursuing enhanced stakeholder participation levels at local levels. A socio-economic survey investigation describing major participation trends against reported property rights and Willingness to Pay values was conducted in the Kat River Valley, Eastern Cape province. From the investigation, observed participation trends driven by economic interests were identified and used in recommendations proposed for the policy implementation process. Using game theoretic arguments as guidelines in soliciting cooperative behaviour in the use and consumption of common resources (Ostrom, 1990), the thesis proposes the introduction of water related public works projects as employment creating vehicles for individuals and communities targeted for economic empowerment and participation in the water policy. However, for sustainable stakeholder participation levels, it is argued that the employment positions created through the projects need to be designed in a manner that would encourage an evolution of long-term relationships between stakeholders and the water management institutions.
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Writing, identity, and change : a narrative case study of the use of journals to promote reflexivity within a Drama Studies curriculum
- Authors: Sutherland, Alexandra
- Date: 2005
- Subjects: Drama -- Study and teaching (Higher) -- South Africa Drama in education Scholarly publishing Academic writing Reflection (Philosophy) Playwriting
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1845 , http://hdl.handle.net/10962/d1004384
- Description: The study adopts a case study examination of three student reflective joumals written about class and field based applied Drama experiences over one year. The journals were written as part of a curriculum outcome to develop reflective practice, for one Drama Honours paper (Educational Drama and Theatre) at Rhodes University Drama Department, South Africa. Based on a narrative inquiry approach, the study documents the changes in identity, discourse, and representation of self and other, which emerge through the journal writing process. The research analyses how identities are constructed through reflective writing practices, and how these identities might relate to the arguments for the development of reflexivity. The development of reflexivity is seen as integral to contemporary educational policies associated with lifelong learning, and the skills required of graduates in South Africa's emerging democracy. These policies centre on means of preparing students for a world characterised by change and instability, or what Barnett (2000) has termed a "supercomplex world". The research findings suggest that journal writing within a Drama Studies curriculum, allows students to construct subjectivities which support Barnett's claim that "the main pedagogical task in a university is not that of the transmission of knowledge but of promoting forms of human being appropriate to the conditions of supercomplexity" (Barnett, 2000b: 164). In addition, the development of different writing genres within a Drama Studies curriculum allows students to develop disciplinarily relevant ways of discussing and researching artistic processes and products. A reflective journal is a potential site for students to interrogate and construct emerging identities which enable them to negotiate diversity, thus preparing them for their lives beyond the university.
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