Female school principals=perceptions of leadership in a male dominated education environment
- Authors: Mwingi, Mweru P
- Date: 2000
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/326 , vital:19948
- Description: Many well-known studies on leadership have ignored the perspective of women yet bear an emphasis on the importance of portraying leadership in its entirety. This would mean that all leadership perspectives are included and that leaders are allowed to speak for themselves and about themselves. It is this connection I have sought to establish how women perceive leadership by relating the experiences of four women in school principalship. I have used a factual questionnaire to establish the background of each one but, it is the in-depth interviews that yield the leadership perceptions. Borrowing from phenomenological procedures, the leadership experiences are related as Natural Meaning Units (NMUS) whereby all prior knowledge and possible bias are bracketed out. Reinforced by their journal entries, it is only the voice of the women that is heard. My study reinforces the observation of researchers and feminist scholars that women leaders are not only marginalised but also viewed from a perspective that is not their own. From the study, however, the one element about leadership that emerges as unique is the functioning of transformational leadership elements among women leaders in educational set-ups that are inherently traditional, bureaucratic and hierarchical. This is significant because there is an indication that women leaders are inclined to transformational leadership because it favours their feminine qualities. There is also evidence that school principals can embrace leadership diversity and finally, that leadership and the structures of leadership operation are not developed from without but from within the person of the leader and this is an incorporation of their vision and beliefs. In the context of South Africa, this study should be of potential significance because of the change that is taking place in the development and training of school principals.
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Genetic variation within and between some rare and common taxa of Cape Proteaceae and the implications for their conservation
- Authors: Brown, Susan Ann
- Date: 2000
- Subjects: Proteaceae -- South Africa Nature conservation -- South Africa Plant conservation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3905 , http://hdl.handle.net/10962/d1003964
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Geographically distributed requirements elicitation
- Authors: Vat, Nicholas
- Date: 2000
- Subjects: Management information systems -- Management , Information resources management , System design , System analysis
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1136 , http://hdl.handle.net/10962/d1002764 , Management information systems -- Management , Information resources management , System design , System analysis
- Description: The technology revolution has transformed the way in which many organisations do their business. The resultant information systems have increased the decision making powers of executives, leading to increased effectiveness and ultimately to improved product delivery. The process of information systems development is, however, complex. Furthermore, it has a poor track record in terms of on-time and within-budget delivery, but more significantly in terms of low user acceptance frequently attributable to poor user requirements specification. Consequently, much attention has been given to the process of requirements elicitation, with both researchers and businessmen seeking new, innovative and effective methods. These methods usually involve large numbers of participants who are drawn from within the client and developer organisations. This is a financially costly characteristic of the requirements elicitation process. Besides information systems, the technology revolution has also brought sophisticated communication technologies into the marketplace. These communication technologies allow people to communicate with one another in a variety of different time and space scenarios. An important spin-off of this is the ability for people located in significantly different geographical locations to work collaboratively on a project. It is claimed that this approach to work has significant cost and productivity advantages. This study draws the requirements elicitation process into the realm of collaborative work. Important project management, communication, and collaborative working principles are examined in detail, and a model is developed which represents these issues as they pertain to the requirements elicitation process. An empirical study (conducted in South Africa) is performed in order to examine the principles of the model and the relationships between its constituent elements. A model of geographically distributed requirements elicitation (GDRE) is developed on the basis of the findings of this investigation. The model of GDRE is presented as a 3-phased approach to requirements elicitation, namely planning, implementation, and termination. Significantly, the model suggests the use of interviews, structured workshops, and prototyping as the chief requirements elicitation methods to be adopted in appropriate conditions. Although a detailed study of communications technology was not performed, this thesis suggests that each individual GDRE implementation requires a different mix of communication technologies to support its implementation.
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Grassroots diplomacy between Lesotho and South Africa: the district liaison committees
- Authors: Moeletsi, Motheba Gwendoline
- Date: 2000
- Subjects: Lesotho -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Lesotho , Africa -- Foreign relations -- 1960- , Africa -- Politics and government -- 1960-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2805 , http://hdl.handle.net/10962/d1003015 , Lesotho -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Lesotho , Africa -- Foreign relations -- 1960- , Africa -- Politics and government -- 1960-
- Description: Cross-border conflicts on the African continent have increased tremendously in the post-colonial years. The widespread border conflicts on the African continent have been attributed to the arbitrariness with which Africa’s national boundaries were drawn during the colonial period. The colonial boundaries have left the doors open for perpetual conflicts among African states. This thesis proposes to investigate the prospects of grassroots diplomacy as an option of dealing with border conflicts with specific reference to the case of Lesotho/South Africa border relations. This is done by critically evaluating the role the District Liaison Committees (DLCs) have played in border relations between Lesotho and South Africa. The Lesotho and South African governments have institutionalised the resolution of border conflicts at grassroots level through the establishment of the DLCs. The DLCs consists of representatives of border communities in Lesotho and South Africa. The paper introduces a not so familiar concept of involving people at grassroots levels in the conducting of diplomacy between the two neighbouring countries. The central issue implicit in this paper is that grassroots diplomacy is succeeding in the case of Lesotho and South Africa. The DLCs have managed to reduce tension between the two countries along the borders which had existed over a long period of time, thereby, relieving the central governments of some of their duties. The thesis contents that high level conventional diplomacy is not always the answer to cross-border conflicts. The example of Lesotho and South Africa could be followed by other African countries in similar situations.
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Healing at the margins: discourses of culture and illness in psychiatrists', psychologists' and indigenous healers' talk about collaboration
- Authors: Yen, Jeffery
- Date: 2000
- Subjects: Traditional medicine -- South Africa , Medical policy -- South Africa , Mental health -- South Africa , Healers -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3090 , http://hdl.handle.net/10962/d1002600 , Traditional medicine -- South Africa , Medical policy -- South Africa , Mental health -- South Africa , Healers -- South Africa
- Description: This dissertation explores discourses about culture and illness in the talk of mental health professionals and indigenous healers. It represents an attempt to situate the issue of indigenous healing in South Africa within a particular strand of critical discourse analytic research. In the context of current deliberations on the value, or otherwise, of indigenous healing in a changing health and specifically mental health system, the talk of both mental health practitioners and indigenous healers as they conceptualise “disorder”, and discuss possibilities for collaboration, is chosen as a specific focus for this study. Disputes over what constitutes “disorder” both within mental health, and between mental health and indigenous healing are an important site in which the negotiation of power relations between mental health professionals and indigenous healers is played out. The results of this study suggest that despite the construction of cogent commendations for the inclusion of indigenous healing in mental health, it remains largely marginalised within talk about mental health practice. While this study reproduces to some extent the marginalisation of indigenous healing discourse, it also examines some of the discursive practices and methodological difficulties implicated in its marginalisation. However, in the context of “cultural pride strategies” associated with talk about an African Renaissance, indigenous healing may also function as a site of assertion of African power and resistance in its construction as an essentially African enterprise. At the same time, it may achieve disciplinary effects consonant with cultural pride strategies, in constructing afflictions in terms of neglect of, or disloyalty to cultural tradition. These results are discussed in terms of the methodological difficulties associated with interviewing and discourse analysis of translated texts, which contributes to difficulties with articulating indigenous healing discourse in a way that challenges the dominant psychiatric discourses implicated in its marginalisation within mental health. It concludes with recommendations for future research which addresses indigenous healing discourse in its own terms, and examines its operation as a disciplinary apparatus in South African society.
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Hidden presences in the spirituality of the amaXhosa of the Eastern Cape and the impact of Christianity on them
- Authors: Mtuze, P T
- Date: 2000
- Subjects: Spirituality -- South Africa -- Eastern Cape , Xhosa (African people) -- Religion , Missions -- South Africa -- Eastern Cape , Missionaries -- South Africa -- Eastern Cape , Christianity -- South Africa -- Eastern Cape -- History , Christianity and culture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTh
- Identifier: vital:1296 , http://hdl.handle.net/10962/d1015612
- Description: This thesis is an attempt to reopen the debate on the whole question of inculturation in Southern Africa especially in light of the fact that we are now in a multi-lingual and multi-religious state. It is an attempt to rehighlight the plight of the spirituality of the amaXhosa people over the last century when missionary and imperial onslaught relegated it to the doldrums. This plunged the amaXhosa in a crisis that has left them directionless, to put it mildly. This is said because the total onslaught destroyed their self-respect and their identity and begs the question as to whether their acceptability to God was contingent on renouncing their culture especially the hidden presences - Qamata, the living-dead and the notion of evil spirits. It is precisely because of these misconceptions regarding African culture and spirituality that the thesis has a strong expository and apologetic bias primarily aimed to address, and put into proper perspective, the significance of the Supreme Being, the living-dead and the evil spirits in African culture. The issues are discussed within the broader socio-historical context. The thesis is basically comparative in that it uses Celtic spirituality and the approach of the early Celtic church to the question of inculturation as its point of departure and as a foil against which the preposterous actions of the church in Africa should be seen. This comparative element is also reflected in the unmistakable `dichotomy’ of Western religion and African spirituality, or better still, lack of spirituality, that was so fervently maintained by the missionaries and the colonialists alike. It is for this reason that I concur with Chidester (1996:xiv) that `the study of religion must find itself, once again, on the frontier’. The study is informed by this approach right through. It should be stressed, from the outset, that the idea is not comparison in order to satisfy our curiosity, nor is it comparison in order to try to authenticate and vindicate the beleaguered African culture. The central idea of the study is to expose the absurdity of the policies of the past century in this regard. The myth of the pure blooded Christianity is confronted, if not exploded. Several examples of both inculturation and continuities between Christianity and other faiths such as the Jewish founding faith are given. The subtheme of cultural domination subtly spans the whole study culminating in Chapter Four where the blacks begin to appropriate some of the Christian symbols and the whites also begin to assimilate African concepts such as ubuntu.
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In time of plague : the Basotho and the rinderpest, 1896-8
- Authors: Phoofolo, Pule
- Date: 2000
- Subjects: Rinderpest -- Lesotho -- History Epidemics -- Africa -- History Livestock -- Diseases -- Africa Sotho (African people) -- Social life and customs Lesotho -- History
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2553 , http://hdl.handle.net/10962/d1002405
- Description: Rinderpest, the most dreaded bovine plague, struck the cattle of the BaSotho in British Basutoland early in 1897. By December the murrain had spent itself, having reduced the cattle population by half As it did so, the rinderpest claimed the primary historical significance of an epidemic. By sharpening behaviour and illuminating latent or developing tendencies, the rinderpest helped to reveal the nooks and crannies of contemporary historical processes that would have otherwise eluded historical visibility. This thesis brings out the complexities and ambiguities surrounding the epidemic. It uses the crisis occasioned by the panzootic in its multifaceted manifestations as a prism through which we might view the complex aspects of contemporary historical processes. It goes beyond the narrow limits of the crisis itself to discerning the broader and wider historical patterns that the rinderpest helped to highlight.
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Key decision-makers' perceptions of sustainable sea fisheries in Namibia and the implications for environmental education programmes
- Authors: Boois, Ulrich
- Date: 2000
- Subjects: Environmental education -- Namibia Fisheries -- Environmental aspects Fisheries -- Environmental aspects -- Namibia Sustainable development -- Environmental aspects Sustainable development -- Environmental aspects -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1661 , http://hdl.handle.net/10962/d1003544
- Description: This study investigates key decision-makers' perceptions of sustainable sea fisheries in Namibia, and explores the possibilities for the future development of education programmes that focus on "sustainability" in the fisheries sector. The concept of "sustainability" and its application in the context of a biological resource, namely sea fisheries, was examined. A series of questions were raised concerning sustainable fisheries: intergenerational implications of patterns of resource use, equity concerns, time horizons, and the protection of marine biodiveristy, among others. Examples from the Namibian and the European Community Sea Fisheries Industries are used to illustrate these issues. In spite of divergent views on what "sustainability" means, the study leads to certain findings that have broader policy implications. Data was collected from semi-structured interviews undertaken with six (6) key decision-makers in the Sea Fisheries Industry of Namibia, then analysed and assessed. The perceptions of key decisionmakers were determined by qualitative analysis in the interpretive paradigm. The data indicated some agreement in terms of what the key decision-makers think about the sustainable utilisation of the fisherjes resources. It is almost impossible to have complete agreement, because the decision-makers are from different contextual backgrounds. Those who make the decisions are more concerned about "how to manage" and those who act on the decisions put more emphasis on economic self-interest. Although the interviewees' perceptions of sustainable fisheries was imperfect, there was broad support for its aims and principles. The study also revealed that the achievement of sustainable sea fisheries development in Wamibia will require broader educational and public awareness programmes to enhance participation in decision-making debates. Formal and informal marine environmental education, from the perspective of "Responsible Fishing" has been emphasised.
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Latent murderousness: an exploration of the nature and quality of object relations in rage-type murderers
- Authors: Cartwright, Duncan James
- Date: 2000
- Subjects: Murder Murder -- Case studies Murderers -- Psychology Criminal psychology Violence Narcissism Aggressiveness Anger
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2946 , http://hdl.handle.net/10962/d1002455
- Description: In this dissertation I investigate the intrapsychic make-up of rage-type offenders and explore the psychodynamics of the act of murder itself The dissertation begins with a discussion on the defining features of the act of rage-type murder. I then consider the role of personality characteristics and psychopathology in individuals who have committed such offences. With the basic features of the offender and act itself outlined, the following section reviews key areas of debate regarding the psychodynamics of violence and the intrapsychic make-up of the rage-type murderer. I first explore the nature of aggression as debated in psychoanalysis and conclude that the views expressed are often unn,ecessarily polarized regarding the origins of aggression and suggest that the specifics of particular types of aggression require consideration in order to assess their intrapsychic nature. The specifics of rage and violence are discussed with this in mind. In the second chapter of this section I develop a number of intrapsychic dimensions to be used in understanding how different types of violence are constituted. Psychodynamic contributions towards understanding rage-type murder, as a specific form of violence, are then discussed. Following this review, a number of directive ~uestions are formulated regarding (1) the intrapsychic dimension of rage-type murder; (2) the pJ;esence of the borderline personality in such offender~ and its intrapsychic nature; and (3) the_ specific psychodynamics that lie behind what is argued to be a defensive act of murder. A multiple case study approach, using nine imprisoned rage-type offenders, is used to further explore the above issues. Court summary reports, the Thematic Apperception Test and the Psychoanalytic Research Interview comprised the research material, with particular emphasis placed on the interview material. The interview is approached from a psychoanalytic perspective and I develop some theoretical, technical and analytical guidelines to try to broaden Jhe use of psychoanalysis in the research domain. Findings of the research reveal a specific kind of defensive organization that is characterized by a constellation of object relations that I term the 'narcissistic exoskeleton'. I suggest that these findings best fit the description of a particular kind of borderline personality organization typified by apparent 'normality'. Other prominent aspects of the dimensions of violence observed in these cases include: (1) a poor representational capacity; (2) an interactional style characterized by uncontainable projective exchanges between victim and offender; (3) a collusive primary object relationship combined with the absence of an internalized 'third object'; (4) a 'two-faced' superego structure; (5) the internalization of traumatic experience that has become associated with a bad object system; (6) phantasies of restoring ideal good in external objects alongside conscious fantasies of annihilation. Within the context of these factors the intrapsychic events that lead to the act itself are discussed. It is found that a collapse of the 'narcissistic exoskeleton', the intrusion of the bad object system and the unbearable shame that this evokes in the offender are prominent features of what culminates in an act of explosive rage and projective identification. Some of the implications of my research are briefly discussed in the concluding chapter.
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Making sense of ʺessenceʺ : a critical examination of the adequacy of the modern philosophical conception of ʺessenceʺ
- Authors: Ross, Allison
- Date: 2000
- Subjects: Essentialism (Philosophy)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2720 , http://hdl.handle.net/10962/d1002850 , Essentialism (Philosophy)
- Description: The idea that some sub-set of the properties of an object captures what it is to be that thing i.e. that it has an essence which is there to be discovered and about which we can be mistaken - is a commonsense assumption that we use all the time. However, philosophers of this century have regarded the realism about essence with skepticism, arguing that we impose essences on things by the way we define our concepts as opposed to discovering them. Essences are supposedly characteristics of our concepts rather than of objects in the world. This was the orthodox view until a group of philosophers of language developed the theory of direct reference. They claimed that proper names and certain other words refer non-connotatively which entails that the real properties of objects are crucial to the establishment of the reference of such terms. It can be shown that the properties involved in reference determination must be all and only the necessary properties of those objects. This discovery has been taken to mark the rehabilitation of the notion of essence, with an object’s essence being taken to be that set of properties which it must have in all possible worlds in which it exists. I will argue that the theory of direct reference is correct up to the point at which it assimilates the necessary properties of objects to their essences. I will show that the set of an object’s necessary properties cannot fulfill the role reserved for the concept of essence in metaphysical hypotheses concerning the nature of objects. I will go on to show that a sub-set of a thing’s necessary properties can fulfill this role and I will suggest that we identify the members of this sub-set by testing their ability to furnish the kinds of explanations we expect from essences. I will demonstrate how this can be done using the Aristotelian idea that the notion of essence is required in order to explain how it is that objects can persist through change.
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Master of Education portfolio
- Authors: Morrison, Paula
- Date: 2000
- Subjects: Environmental education -- South Africa -- Kwazulu Natal
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1671 , http://hdl.handle.net/10962/d1003554
- Description: This report is the culmination of a six year process during which emerged the need to establish a meeting or indaba place for the collaborative 'People and Parks' partnership of the KwaZulu-Natal Nature Conservation Service (NCS) in Hluhluwe-Umfolozi Park (HUP) and stake-holder communities adjacent to the Park. Comprising two parts which compliment each other, the report has been developed to inform, guide and advise the NCS in the planning and development of an education centre in Hluhluwe-Umfolozi Park. Part I documents the processes of engagement and interaction between the NCS in HUP and neighbouring communities during this period, which led to the need for an education centre, whilst placing and contextualizing the process within historical, socio-political and organisational processes. This is taken further with a description of the research process and an analytical narrative of four key programmes. Part I concludes with a summary of the outcomes of the planning process which shows how through local community input and partiCipation, and through networking with other EE practitioners, a conceptual development plan for the Mambeni Education Centre emerged. The second part of this report (Part 2) is the conceptual development plan which has emerged out of the processes described in Part 1. This plan constitutes practical guidelines for the NCS on how to develop and manage the Mambeni Education Centre. More specifically the plan provides ideas about: what type of centre it should be and where it should be located; who the stake-holders are, their educational neees and ideas for possible programmes; the physical and logistical requirements; managemynt and staffing structures and a detailed business plan. The report intends to draw the reader into understanding the complex social and environmental issues that the collaborative partnership of 'People and Parks' are engaging with, so that the Mambeni Environmental Education Centre can playa [more] meaningful and responsive role in contributing to processes of social transformation. In sharing this environmental education re(search) story which represents a unique approach to centre development, it is hoped that the notion of environmental education centres might be viewed by environmental educators through a different set of lenses. Through having the participants' views represented, I wish the report to reflect the richness of the research process.
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Materials in flexible learning teacher education courses in environmental education : an evaluative case study
- Authors: Molose, Vivian Innotantia
- Date: 2000
- Subjects: Environmental education -- Study and teaching Environmental education -- Study and teaching -- Evaluation Environmental education -- South Africa -- Study and teaching
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1672 , http://hdl.handle.net/10962/d1003555
- Description: The study aimed at researching the role of materials in flexible learning teacher education courses, specifically looking at the Eastern Cape Teacher Course as a case study. The research aimed at exploring how courses and materials were developed, selected, used and adapted or redeveloped so as to support the course orientation and the intended outcomes. I did this with the hope that my research might inform the process of improving the role of course materials in flexible learning teacher education courses. I did a naturalistic enquiry within which I interviewed 39 participants (teachers and teacher educators) and two course co-ordinators. I also analysed documents such as the course materials, nine participants' journals and seven of their assignments. The observation notes compiled during the early days of the course were not used as a main source of data but as support to data sources mentioned above. Questionnaires were handed out to all the course participants, i.e. course co-ordinators, tutors and student participants. The questionnaires were intended as a means for pre interview and post interview reflection for interviewees. Through this research, I have learnt a lot about the role of materials in professional development courses, including the importance of mediation of materials and their overt use during course sessions, the importance of providing and encouraging a culture of reading through time allocation during contact sessions, through discussions on materials, and also through providing orientating comm~nts on materials rather than just handing them out to participants. Readings that are more focussed do better to motivate participants to interact with them.
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Mesozooplankton community structure in the vicinity of the Prince Edward Islands (Southern Ocean) 37⁰ 50'E, 46⁰ 45'S
- Authors: Hunt, Brian Peter Vere
- Date: 2000
- Subjects: Zooplankton , Zooplankton -- Prince Edward Islands , Phytoplankton , Chlorophyll
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5732 , http://hdl.handle.net/10962/d1005418 , Zooplankton , Zooplankton -- Prince Edward Islands , Phytoplankton , Chlorophyll
- Description: Mesozooplankton community structure in the vicinity of the Prince Edward Islands (PEIs) was investigated during six surveys conducted in late austral summer (April/May), 1996 to 1999. Each year zooplankton samples were collected with a bongo net (300 µm mesh) at stations upstream (west), between and downstream (east) of the islands. Chlorophyll a concentrations were determined fluorometrically, corresponding with each net tow. The positions of the Subantarctic Front (SAF) and the Antarctic Polar Front (APF), in relation to the islands in the upstream region, were determined by a line of CTD and/or XBT stations. Both the SAF and the APF were characterised by a high degree of meridional variation in position. Changes in position of the fronts were shown to occur very rapidly. In 1999 the APF moved southwards by ~40nm and the SAF northwards by ~60nm in a period of two weeks, while in 1996 the SAF appeared to move ~120nm northwards in a two week period. The positions of the SAF and APF appeared to have a significant impact on phytoplankton biomass in the vicinity of the PEIs, through the alteration of local flow dynamics. Water retention in 1996, associated with the location of the SAF and APF far to the north and south of the PEIs respectively, corresponded with high chlorophyll a concentrations in the inter-island region (reaching 1.54 mg.m^(-3)). When the fronts were close to the islands, in 1997 and 1999, and a flow through environment existed, chlorophyll a concentrations in the inter-island region were comparatively low. Although biomass enhancement was only observed at the SAF in 1996, phytoplankton size structure in 1999 indicated that, when close to the PEIs, frontal production may be transported to the island system. This is potentially an important source of allochthonous input into the island system. Zooplankton assemblages were a mix of sub-Antarctic and Antarctic communities, with a weak presence of sub-tropical species. Cluster analysis showed that during each survey the region in the vicinity of the PEIs was divided into different, spatially separated zooplankton communities, associated with water masses of different origins. These communities were identified by variations in the abundance and biomass of species rather than variation in species composition and, in general, there was a relatively high degree of similarity both within and between surveys. Inter-annual community analysis revealed that, in many cases, there was greater similarity between communities from different years than communities within years, indicating that short-term variability exceeded inter-annual variability. Multiple regression analysis showed that the major correlate with zooplankton community structure during all surveys was sea temperature, accounting for as much as 77% of the variation in community structure. Temperature was indicative of the relative contribution of sub-Antarctic and Antarctic communities, with low temperatures being characterised by an increased predominance of Antarctic communities and vice versa. The differentiation between sub-Antarctic and Antarctic waters, and their respective communities, was particularly pronounced when the SAF and APF were in close proximity to the islands. Surface salinity and sounding had limited effect on community structure. The affect of sounding was intrinsically related to zooplankton interaction with the island ecosystem. Predation by the islands' land based predators and benthic fish appears to decrease zooplankton biomass over the island shelf, particularly the macrozooplankton size fraction. However, this may only be an important factor under conditions of water retention when replenishment of zooplankton stocks is low. The low densities of many macrozooplankton species, and other deep migrators, on the island shelf may be due to their limited advection onto shallow topography. By contrast, there are indications that zooplankton species occurring at shallower depths may be concentrated in the inter-island region by mesoscale flow patterns. Analysis of the population structure of the copepod Calanus simillimus showed that this species occurred at different stages in its life cycle during different years, even though sampling took place in the same calendar months, indicating that there was inter-annual variation in the timing of the biological season. Differences in the population structure of species, and consequently their contribution to abundance and biomass, may therefore have been an important contributor to inter-annual variation in community structure. Evidence is provided for a long-term trend of southward movement of the SAF. This may have a significant affect on the PEI ecosystem, increasing the proportion of allochthonous input and altering the tropho-dynamics of the island ecosystem
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Methods for designing and optimizing fuzzy controllers
- Authors: Swartz, Andre Michael
- Date: 2000
- Subjects: Fuzzy sets , Fuzzy systems , Automatic control
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5412 , http://hdl.handle.net/10962/d1005226 , Fuzzy sets , Fuzzy systems , Automatic control
- Description: We start by discussing fuzzy sets and the algebra of fuzzy sets. We consider some properties of fuzzy modeling tools. This is followed by considering the Mamdani and Sugeno models for designing fuzzy controllers. Various methods for using sets of data for desining controllers are discussed. This is followed by a chapter illustrating the use of genetic algorithms in designing and optimizing fuzzy controllers.Finally we look at some previous applications of fuzzy control in telecommunication networks, and illustrate a simple application that was developed as part of the present work.
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Microemulsions : a new perspective in the treatment of paediatric and geriatric tuberculosis patients
- Authors: Wisch, Michael Henry
- Date: 2000
- Subjects: Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3805 , http://hdl.handle.net/10962/d1003283 , Emulsions (Pharmacy) , Tuberculosis -- Treatment -- South Africa , Tuberculosis in children -- Treatment , Tuberculosis in old age -- Treatment , Tuberculosis -- Treatment
- Description: Tuberculosis(TB) was declared to be a global emergency in 1993, with South Africa declaring it to be the country’s top health priority in 1996, but ineffective treatment strategies have led to fewer than half of all treated patients in South Africa being cured. At present,paediatric treatment remains a problem, as the antitubercular preparations of rifampicin, isoniazid and pyrazinamide, that are currently available, were not initially designed for the treatment of paediatric TB patients, providing a motivation for this project. The aim of this project is thus the development of a microemulsion dosage form for the oral delivery of RIF(Rifampicin), INH(Isoniazid) and PZA(Pyrazinamide) in combination. RIF, INH and PZA were adequately characterised with reference to the monograph standards referenced and were found to be sufficiently pure to be used in subsequent work. A chromatographic system and conditions were selected and validated as being optimal for HPLC analysis of RIF, INH and PZA in combination, with a drug partitioning method for miglyol 812 developed and validated. Ternary and pseudo-ternary phase diagrams were constructed and reported, all employing miglyol 812 as the lipid. It was undoubtedly the imwitor 308 and crillet 3 combination o/w microemulsion system that proved most successful, maintaining homogeneity on dilution. The microemulsion used in formulation comprised imwitor 308 (27.63%), crillet 3 (27.63%), miglyol 812 23.68%) and water (21.06%). The stability of RIF, INH and PZA was investigated in aqueous solution, miglyol 812, corn oil, 10%m/v cremophor RH, 5%m/v imwitor 308, 10%m/v crillet 3 and 70%m/v sorbitol solution. Trends in the stability assessments conducted on RIF, INH and PZA were noted, with slight variation depending on the formulation component being evaluated. RIF invariably demonstrated temperature and oxidation dependent degradation in all vehicles, with a definite distinction possible between samples stored at 25, 40 and 600C over a 7 day trial period. A definite advantage of storing RIF solutions under nitrogen was observed, with these solutions showing less degradation over the course of the trial, than those stored under air. INH produced a pronounced increase in the degree of degradation of RIF, whereas PZA had a negligible effect on it’s stability. INH proved to be most stable in the 70%m/v sorbitol solution with no significant oxidation or temperature dependent degradation indicated. Temperature dependent degradation was only noticable when INH was in combination with RIF, most significant in crillet 3 solution. PZA was the most stable of the three drugs, remaining relatively unaffected by temperature and the presence of air, independent of the vehicle employed, although the drug remaining did decrease slightly in the presence of RIF.Due to drug dose specifications and solubility limitations, the final formulation assessed, only contained RIF and INH, despite INH and PZA having no significant effect on the stability of each other. The solubility of PZA in the lipid and aqueous components of the microemulsion was not great enough to achieve the required 500 mg/10ml dose, while RIF and INH could achieve the respective 150mg/10ml and 100mg/10ml dose. RIF stability was improved, as anticipated, with the incorporation of RIF into the internal phase decreasing contact with INH which has been shown to affect it’s stability. RIF behaved as predicted, possessing greater stability than shown in the individual formulation components, however, INH did not, being less stable in formulation in the absence of antioxidant, than in it’s presence. A novel microemulsion formulation capable of delivering the incompatible RIF and INH in combination, with numerous microemulsion systems mapped,with the ability of being used for the delivery of other lipophilic drugs and drug combinations, was produced.The final formulation provided valuable information into possible future improvements of the microemulsion to improve drug stability.
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Minimal motion capture with inverse kinematics for articulated human figure animation
- Authors: Casanueva, Luis
- Date: 2000
- Subjects: Virtual reality , Image processing -- Digital techniques
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4620 , http://hdl.handle.net/10962/d1006485 , Virtual reality , Image processing -- Digital techniques
- Description: Animating an articulated figure usually requires expensive hardware in terms of motion capture equipment, processing power and rendering power. This implies a high cost system and thus eliminates the use of personal computers to drive avatars in virtual environments. We propose a system to animate an articulated human upper body in real-time, using minimal motion capture trackers to provide position and orientation for the limbs. The system has to drive an avatar in a virtual environment on a low-end computer. The cost of the motion capture equipment must be relatively low (hence the use of minimal trackers). We discuss the various types of motion capture equipment and decide to use electromagnetic trackers which are adequate for our requirements while being reasonably priced. We also discuss the use of inverse kinematics to solve for the articulated chains making up the topology of the articulated figure. Furthermore, we offer a method to describe articulated chains as well as a process to specify the reach of up to four link chains with various levels of redundancy for use in articulated figures. We then provide various types of constraints to reduce the redundancy of non-defined articulated chains, specifically for chains found in an articulated human upper body. Such methods include a way to solve for the redundancy in the orientation of the neck link, as well as three different methods to solve the redundancy of the articulated human arm. The first method involves eliminating a degree of freedom from the chain, thus reducing its redundancy. The second method calculates the elevation angle of the elbow position from the elevation angle of the hand. The third method determines the actual position of the elbow from an average of previous positions of the elbow according to the position and orientation of the hand. The previous positions of the elbow are captured during the calibration process. The redundancy of the neck is easily solved due to the small amount of redundancy in the chain. When solving the arm, the first method which should give a perfect result in theory, gives a poor result in practice due to the limitations of both the motion capture equipment and the design. The second method provides an adequate result for the position of the redundant elbow in most cases although fails in some cases. Still it benefits from a simple approach as well as very little need for calibration. The third method provides the most accurate method of the three for the position of the redundant elbow although it also fails in some cases. This method however requires a long calibration session for each user. The last two methods allow for the calibration data to be used in latter session, thus reducing considerably the calibration required. In combination with a virtual reality system, these processes allow for the real-time animation of an articulated figure to drive avatars in virtual environments or for low quality animation on a low-end computer.
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Minor "dings" - major effects? a study into the cognitive effects of mild head injuries in high school rugby
- Authors: Ackermann, Tessa Ruth
- Date: 2000
- Subjects: Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Head -- Wounds and injuries -- Patients -- Rehabilitation
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2920 , http://hdl.handle.net/10962/d1002429 , Rugby football injuries , Head -- Wounds and injuries -- Psychology , Head -- Wounds and injuries -- Complications , Head -- Wounds and injuries -- Patients -- Rehabilitation
- Description: The present study is part of a larger and ongoing research initiative investigating the cumulative cognitive effects of mild head injury in rugby union and focused specifically on high school rugby players. A comprehensive battery of neuropsychological tests was administered to top team high school rugby players (n = 47), and a non-contact sport control group of top team high school hockey players (n = 34). Direct comparisons of group mean scores and standard deviations across each neuropsychological test were carried out for the Total Rugby group versus the Total Hockey group as well as for the subgroups Rugby Forwards versus Rugby Backs. A correlational analysis was conducted to ascertain whether a relationship exists between the number of mild head injuries reported by the players and their cognitive test performance. Results of the group comparisons of means and variability on WMS Paired Associate Learning Hard Pairs - Delayed Recall provides tentative indications of the initial stages of diffuse damage associated with mild head injury in the rugby group and provides some evidence for impairment of verbal learning and memory in the Rugby Forwards group. The correlational analysis revealed no significant relationship between number of reported mild head injuries and cognitive performance. The findings and possible latent effects of the multiple mild head injuries reported by the rugby players are discussed in terms of brain reserve capacity theory and suggestions for future research are provided.
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Morphological development in the interlanguage of English learners of Xhosa
- Authors: Hobson, Carol Bonnin
- Date: 2000
- Subjects: Grammar, Comparative and general -- Morphology Xhosa language -- Foreign speakers Xhosa language -- Morphology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2348 , http://hdl.handle.net/10962/d1002630
- Description: This study investigates the development of morphology in the interlanguage of English learners of Xhosa. A quasi-longitudinal research design is used to trace development in the oral interlanguage of six learners of Xhosa for a period of eight months. The elicitation tasks employed range from fairly unstructured conversation tasks to highly structured sentence-manipulation tasks. The learners have varying levels of competence at the beginning of the study and they are exposed to input mainly in formal contexts of learning. One of the aims of the study is to investigate whether the features of interlanguage identified in other studies appear in the learner language in this study. Most other studies discussed in the literature have investigated the features of the interlanguage produced by learners of analytic and inflectional languages. However, this study analyses the interlanguage of learners of an agglutinative language. Studies of other languages have concluded that learners do not use inflectional or agreement morphology at early stages of development and this conclusion is tested for learners of an agglutinative language in this study. Since agreement and inflectional morphology play a central role in conveying meaning in Xhosa, it is found that learners use morphology from the beginning of the learning process. Although forms may be used incorrectly and the functions of forms may be restricted, morphemes appear in the interlanguage of learners of this study earlier than other studies predict. One of the characteristics of early interlanguage and an early form of learner language called the Basic Variety (Klein & Perdue 1997) is the lack of morphology, but this feature proves to be inadequate as a measure of early development in the interlanguage of learners of a language such as Xhosa. This study concludes, therefore, that the presence of morphology in the interlanguage of learners of Xhosa cannot be an indicator of advanced language development.
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Nyau masquerade performance : shifting the imperial gaze
- Authors: Guhrs, Tamara
- Date: 2000
- Subjects: Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2140 , http://hdl.handle.net/10962/d1002372 , Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Description: Nyau Masquerades have been studied by missionaries, anthropologists and religious specialists, but have seldom been documented by theatre and performance specialists. This dissertation argues for the acceptance of Ny au performance as a contemporary world theatre form rooted in tradition. Charting the uneasy relationship between the Nyau and those who have sought to record their performances, the author delineates a vivid dramaturgy of this art form. In doing so, the boundaries of what define theatre as it has traditionally been understood in dominant discourses are made more fluid. Nyau performances have been affected by Colonial processes in varied ways. They were banned by the former government of Northern Rhodesia and severely censored by Catholic Mission teachings in the former Nyasaland. Other forms of vilification have been more subtle. Information about performance in Africa has often been collected and arranged in ways which limit the understanding of these genres. Images of Africa which cluster around the notion of the 'Primitive Other' have enabled a representation of Ny au masking as a superstitious and outdated practice with no relevance for contemporary Africa. This work calls for a new examination of the Nyau, through the lens of local discourse as well as contemporary global understandings of performance. Chapter One examines the issue of primitivism and the ways in which Africa has historically been posited as the exotic Other to Europe. Chapter Two examines the Nyau ih terms of specific dramaturgical elements, adjusting previous misconceptions surrounding the theatr~ forms of Chewa and Nyanja people. Chapter Three is devoted to a discussion of space in ritual theatre and Nyau performance, while Chapter Four explores masking and questions of transformation and liminality. In conclusion, it is seen that the use of the mask is a metaphor for the suspension of rigid boundaries separating subject/object, self/other, ritual/theatre, a suspension which needs to take place before an enriched understanding of performance in Africa can be reached.
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Observations of selective feeding of the aphid, Sitobion yakini (eastop) on leaf blades of barley (Hordeum vulgare L)
- Authors: Matsiliza, Babalwa
- Date: 2000
- Subjects: Aphids , Phloem , Barley
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4212 , http://hdl.handle.net/10962/d1003781 , Aphids , Phloem , Barley
- Description: Penetration of leaves of barley (Hordeum vulgare L.) plants grown under normal conditions and those exposed to physiological stress, by the aphid, Sitobion yakini was investigated using light and electron microscope techniques. This was carried out to determine if there was evidence of preferential feeding on either thin- or thick-walled sieve tubes in the barley leaf. Under both stress and non-stress conditions, preliminary results of an electron microscope investigation showed that penetration of the epidermis and mesophyll was largely intercellular, becoming partly intercellular and in part intracellular inside the vascular bundle. A total of 317 stylets and stylet tracks were encountered during the examination of 2000 serial sections. In non-stressed plant material, 293 (92%) terminated in thin-walled sieve tubes and only 24 (8%) in thick-walled sieve tubes. Investigation of 1000 serial sections using stressed plant material showed, that 84 of 89 (94%) stylets and stylet tracks encountered terminated in thin-walled sieve tubes. Furthermore, 90 of 94 (96%) stylets and stylet tracks encountered in 1000 serial sections from the second experiment of control non-stressed plant material (control) terminated in thin-walled sieve tubes. The thin-walled sieve tubes were significantly more visited (probed) by the aphid than the thick-walled sieve tubes. Under stress conditions, 50 of 89 (56%) stylets and stylet tracks which terminated in thin-walled sieve tubes were associated with the small longitudinal bundles. Under normal conditions, 65 of 94 (69%) stylets and stylet tracks which terminated in thin-walled sieve tubes were associated with the small longitudinal bundles. There were no significant differences on the number of probes of sieve elements between the two treatments. These data suggest that the aphid S. yakini feeds preferentially on the thin-walled sieve tubes of the small longitudinal vascular bundles in plants grown under normal conditions and those exposed to physiological stress, such as water stress. This further suggests that the thin-walled sieve tubes in barley leaf blades are more attractive to the aphid and are probably most functional in terms of phloem loading and transport.
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