List of Titles

Towards the two-way symmetrical communication model: the use of social media to create dialogue around brands

Authors: Matthee, Christelle
Date: 2011
Subjects: Social media , Public relations
Language: English
Type: Thesis , Masters , MA
Identifier: vital:8385 , http://hdl.handle.net/10948/1370 , Social media , Public relations
Description: Social media has radically altered today's media landscape, and presents public relations practitioners with new possibilities and opportunities to promote their companies. Social media enables public relations to observe in order to find out what people need; what content they are looking for; and how your company can help them. However, will engaging in online conversations give an organisation‘s consumers a voice? Past PR models illustrate how methods of communication was established and used in the past. However, the Grunig and Hunt two-way symmetrical model creates the possibility of two-way communication (dialogue) between consumer and organisation in which the power relations are equal. By applying Web 2.0 (social media) to these models, one can explore new ways of two-way communication. Finally by applying these elements to each other, a case study can be created to prove if social media can be used to create a dialogue between consumer and organization.
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Date Issued: 2011

Food gardens, environmental lesson planning and active learning in the life orientation learning area - foundation phase: a case study at Lungelolethu Lower and Higher Primary School

- Ncula, Ntombizandile Shirley

Authors: Ncula, Ntombizandile Shirley
Date: 2007
Subjects: School gardens -- South Africa -- Eastern Cape Gardening -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Environmental education -- Study and teaching (Elementary) -- South Africa --Eastern Cape Environmental education -- South Africa -- Eastern Cape -- Case studies
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1546 , http://hdl.handle.net/10962/d1003428
Description: This study was conducted at Lungelolethu Lower/Higher Primary School in Keiskammahoek at a time when I was struggling to understand and implement the new South African curriculum policy, particularly in the Foundation Phase Life Skills Learning Programme. The research focused on my developing an understanding of key Learning Outcomes and linking them with the National Curriculum Statement principle of social justice, human rights, a healthy environment and inclusivity. During this time I was the key 4-H Programme educator in my school, responsible for school food garden activities. I used the school food garden for this study to explore the opportunities the garden might provide to develop the new curriculum using active learning approaches to teaching and learning; as well as to respond to environmental issues such as poverty. This research was an interpretive case study which supported my reflections within a practical action research framework. This framework suited my intention to change my classroom practice. I undertook three action research cycles with the first cycle aimed at gaining insights from the 4-H Programme teachers which informed 2 lesson plans for cycles 2 and 3 respectively. I generated data through focus group interviews, observations, document analysis, video and tape recording, and my research journal entries. The data indicated the value of school food gardens in meeting curriculum requirements, particularly in relation to learner centred ideologies and the first principle of the national curriculum. As both researcher and mediator of learning, I developed skills and knowledge that helped me to understand working in the Foundation Phase. The study also revealed a need for meaningful integration within and across Learning Areas when planning lessons in the Life Skills Learning Programme. The study indicated that there is a need to develop assessment practices beyond a technical exercise to a more interpretive approach. Lastly this study offers some recommendations for further research into the use of school food gardens through taking the context of learners into account and by encouraging school community relationships that will also contribute in poverty alleviation.
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Date Issued: 2007

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Satellite television use among Zimbabwean professionals : an investigation into audience consumption of SABC Africa's '60 Minutes live in Africa'

- Mugoni, Petronella Chipo

Authors: Mugoni, Petronella Chipo
Date: 2007
Subjects: Direct broadcast satellite television -- Zimbabwe Television viewers -- Zimbabwe Television viewers -- Zimbabwe -- Case studies Television broadcasting of news -- Zimbabwe
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3512 , http://hdl.handle.net/10962/d1007707
Description: Within the context of debates surrounding the consumption of global media by local audiences in Third World countries, this study explores the reasons behind satellite television subscription, and consumption of international news among a sample of young professional men and women in contemporary Zimbabwe. The study seeks to uncover how the research participants respond to news broadcast on SABC Africa's '60 minutes live in Africa', a programme which they can only access via satellite television in their country. Working within the frame of audience studies which insists on understanding media consumption and reception in context, this study examines how the respondents, situated within the specific Zimbabwe context, characterised as it is by serious social, economic and political challenges, respond to both regional news and news about their country on '60 minutes live in Africa'. Within the frame of qualitative research the study employs a two-stage sampling procedure and data collection strategy to uncover the factors that underpin international media consumption and reception by professional men and women situated in a country undergoing rapid change. The findings of the study point to the various social and individual factors that underlie media consumption choices as well as to the different socially patterned reasons why local audiences are either attracted to, or reject global media. The study found that SABC Africa's '60 minutes live in Africa' is more popular and better received than Western-broadcast programmes on channels such as BBC, CNN, and Sky News among Zimbabwean professionals. I also uncovered some evidence that cultural proximity and relevance are of supreme importance in determining which media audiences chose to consume and what level of engagement they bring to their reception of global media. These and other findings directly confront media models that privilege beliefs in cultural imperialism and the dominance of Western media and their effects on Third World audiences.
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Date Issued: 2007

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The viability of small-scale farming at the Tyhefu Irrigation Scheme, Eastern Cape

- Sishuta, Happy Babalwa

Authors: Sishuta, Happy Babalwa
Date: 2004
Subjects: Farms, Small -- South Africa -- Eastern Cape , Irrigation -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3344 , http://hdl.handle.net/10962/d1004924 , Farms, Small -- South Africa -- Eastern Cape , Irrigation -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape
Description: This investigation is conducted against the background of current attempts to rehabilitate and revive the now defunct Tyhefu irrigation scheme. The poor track record of many irrigation schemes (despite huge investments) in the former homelands has prompted the government to reconsider its active and direct role in small-scale irrigation farming. This has resulted in the closure of many irrigation schemes including Tyhefu irrigation scheme. The new policy framework in South Africa, known as the irrigation management transfer, is premised on the transfer of ownership, authority and responsibility of small-scale irrigation schemes from government to the farmers. Tyhefu irrigation scheme was a state-driven, top-down initiative. This study argues that the justifications for the Tyhefu irrigation scheme were conflated, with the result that the need for political control of the Tyhefu area far outweighed the considerations regarding the financial viability and sustainability of the proposed project. Given the repressive political climate of the time in South Africa, the planners' proposals were a mechanism for the realization of the socio-political and economic agendas of the apartheid state and Ciskei government. Although technical factors critical for project success were examined, little or no attention was paid to the socio-economic aspects. For the planners, the main requirements for success entailed centralized managerial control, no participation of the beneficiaries, capital intensive and sophisticated agricultural techniques and the production of high value crops. Therefore, it can be argued that the nature of the planning and implementation of the Tyhefu irrigation scheme was ill-conceived, short-sighted and misguided. A review of the literature on irrigation development on the African continent provided useful insights for this study. The lessons from irrigation development experience in Sub-Saharan Africa indicate that the continent is littered with examples of derelict and costly failures. What stands out in many of these irrigation projects is their over-emphasis on technical issues to the complete neglect of human and other social aspects. Working partnerships between the farmers and irrigation scheme management could, thus, not be realized. Almost without exception the case studies used here indicate that the industrious type of farmer was never developed as was envisioned in the planning documents. Neither were rural livelihoods improved in a sustainable manner. The findings of this study suggest that irrigation management transfer is a complex and delicate process. In this new set of arrangements, beneficiaries face formidable challenges in terms of capacity (human and financial) if small-scale irrigation farming is to become a viable sector. No doubt, the viability and sustainability of the Tyhefu irrigation scheme demands a comprehensive package of interventions that address various issues of markets and marketing, capital investment and access to finance, technology, education and training, support and extension services. It is evident that institutional aspects and the related issue of functional literacy require much more attention than thus far. As a result, at the moment there is no possibility for independent agricultural production. , KMBT_363
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Date Issued: 2004

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An exploration of functional and numerical flexibility in South African organisations: a qualitative study in two textile factories in Cape Town

- Sela, Ronit

Authors: Sela, Ronit
Date: 2002
Subjects: Business enterprises -- South Africa -- Case studies , Industrial management -- South Africa
Language: English
Type: Thesis , Masters , MCom
Identifier: vital:3347 , http://hdl.handle.net/10962/d1006149 , Business enterprises -- South Africa -- Case studies , Industrial management -- South Africa
Description: During this research, an attempt was made to gain an understanding of management and their employees' perceptions regarding functional and numerical flexibility practices within South African organisations. To achieve this, twenty-six people, comprising of a variability of positions within the organisation, were interviewed in the region of the Western Cape. It was found that, although extensive research on the two forms of flexibility have been globally conducted, South African literature, particularly on the part of numerical flexibility, is limited. It is thus believed that this study will present a valuable basis to pursue in further research. Literature that was consulted was found to be supportive of the theoretical notion that South African organisations, in order to be globally competitive, have had to restructure and redefine themselves by ensuring that they make the most efficient and effective use of their human resources. The study found that whilst functional flexibility practices benefit employees in that they experienced increased job satisfaction and job mobility, it was the area of numerical flexibility which raised many dissatisfactions, including those of immense job insecurity and remuneration, both financial and otherwise. The study findings suggest a need for a more comprehensive and employee integrated approach by combining organisational with individual oriented initiatives, and ensuring the trade union's involvement in all facets of functional and numerical flexibility initiatives. The thesis ends with recommendations of various strategies for addressing the concerns of management, employees and the trade union in order to ensure full and proper utilisation of human resources so that the end product, namely job satisfaction, leads to organisational success.
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Date Issued: 2002

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SoDA : a model for the administration of separation of duty requirements in workflow systems

- Perelson, Stephen

Authors: Perelson, Stephen
Date: 2001
Subjects: Electronic data processing departments -- Security measures , Computers -- Access control
Language: English
Type: Thesis , Masters , MTech (Information Technology)
Identifier: vital:10796 , http://hdl.handle.net/10948/68 , Electronic data processing departments -- Security measures , Computers -- Access control
Description: The increasing reliance on information technology to support business processes has emphasised the need for information security mechanisms. This, however, has resulted in an ever-increasing workload in terms of security administration. Security administration encompasses the activity of ensuring the correct enforcement of access control within an organisation. Access rights and their allocation are dictated by the security policies within an organisation. As such, security administration can be seen as a policybased approach. Policy-based approaches promise to lighten the workload of security administrators. Separation of duties is one of the principles cited as a criterion when setting up these policy-based mechanisms. Different types of separation of duty policies exist. They can be categorised into policies that can be enforced at administration time, viz. static separation of duty requirements and policies that can be enforced only at execution time, viz. dynamic separation of duty requirements. This dissertation deals with the specification of both static separation of duty requirements and dynamic separation of duty requirements in role-based workflow environments. It proposes a model for the specification of separation of duty requirements, the expressions of which are based on set theory. The model focuses, furthermore, on the enforcement of static separation of duty. The enforcement of static separation of duty requirements is modelled in terms of invariant conditions. The invariant conditions specify restrictions upon the elements allowed in the sets representing access control requirements. The sets are themselves expressed as database tables within a relational database management system. Algorithms that stipulate how to verify the additions or deletions of elements within these sets can then be performed within the database management system. A prototype was developed in order to demonstrate the concepts of this model. This prototype helps demonstrate how the proposed model could function and flaunts its effectiveness.
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Date Issued: 2001

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A critical investigation of a planned organisation change initiative within an educational institution in the Eastern Cape Province

- Irvine, Margaret Hillian

Authors: Irvine, Margaret Hillian
Date: 2000
Subjects: School management and organization -- South Africa -- Evaluation Education and state Educational change -- South Africa -- Eastern Cape Education -- Economic aspects Organizational change -- South Africa -- Management Non-governmental organizations -- South Africa -- Eastern Cape School management and organization -- South Africa -- Eastern Cape
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1479 , http://hdl.handle.net/10962/d1003360
Description: South Africa is living is turbulent times at present. Non-government educational organisations are challenged by changes in education policy and by scarcity of donor funding for their work. This study focuses on the management of organisation change in a non-government organisation (NGO) working in rural areas of the Eastern Cape Province. I undertook the research to gain a clearer understanding of the management of organisational change. I used a third-wave change management approach, the future search conference, to conduct the process of change with the NGO. It focuses on the positive aspects of the organisation, its potential and its desired future. I conducted both the study and the future search conference as participatory action research, which involved the participants in the cycles of planning, action, observation and reflection and thus built ownership of the solutions they generated. I used the accounts of the activities arising from the future search conference, minutes of meetings, semistructured interviews and observation of behaviour to gather data. I analysed the data using triangulation, and in particular, space triangulation, to minimise the impact of the differences in culture and language use in the facilitator and participants. Analysis of the data collected revealed in the NGO that change and transformation are slow processes requiring ongoing support from the OD consultant. The staff defined organisational effectiveness, the goal of organisational change initiatives, in terms of fundraising ability. This ability embraces many of the qualities of a learning organisation and open systems thinking, two requirements for successful organisational change. In the NGO both organisation development and transformation were processes as well as products, and changes could not easily be measured until after the processes were completed. Organisational culture, and in particular the juxtaposition of the values of the organisation and staff and those of its partners and clients, played an important role in transformation. The differences lay in a ‘being’ and a ‘task’ orientation and the staff’s responsibility lay in building connections between the two. The staff received the approach of the future search conference well and there was an equally good fit between the future search conference and participatory action research. This needs to be investigated further with regard to change management in South African organisations.
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Date Issued: 2000

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A history of the Good Shepherd School, Huntley Street, Grahamstown

- Holshausen, Nicole

Authors: Holshausen, Nicole
Date: 1999
Subjects: Good Shepherd School (South Africa) -- History Schools -- South Africa -- Eastern Cape Schools -- Grahamstown (South Africa)
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1554 , http://hdl.handle.net/10962/d1003436
Description: This thesis is a qualitative, historical study of The Good Shepherd School in Huntly Street, Grahamstown, South Africa. It is one of the oldest school buildings in South Africa that remains in use as a school. There are two main threads to understanding The Good Shepherd School in context. The first of these threads, the colonial root of the school, is explained in a discussion of the Grammar School, attached to the Cathedral of St. Michael and St. George, that utilised the Huntly Street facilities from 1851 to 1902. The second thread is the strong tradition of caring for the underprivileged. This is traced through following the development of the educational works of The Community of the Resurrection which involves the discussion of various schools at different locations in Grahamstown. The current school on the Huntly Street premises, The Good Shepherd School, forms, however, the focus of this study, which draws on all the histories of its forerunners and their historical locations. Historical social science methods and procedures were used in the research. This was done through documentary analysis of evidence as well as through semi-structured interviews, creating an interpretative account of how the school has affected people's lives. The conclusion reached is that The Good Shepherd School has contributed greatly to the education of underprivileged people in the Grahamstown area. It appears to be an outstanding example of a school offering a well-rounded, caring education when this was historically denied to many people in South Africa.
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Date Issued: 1999

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An investigation into the use of a nature reserve as a cross-curricular teaching resource

- Luckhoff, Augusta Henrietta

Authors: Luckhoff, Augusta Henrietta
Date: 1996
Subjects: Environmental education -- South Africa National parks and reserves -- South Africa
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1616 , http://hdl.handle.net/10962/d1003498
Description: This study documents the development of the Queenstown nature reserve as a cross-curricular tea~hing resource. Participants in the project included the researcher, the municipality nature conservation officer and the senior Geography and Biology teachers from five high schools in the town. A modified action research approach was adopted. Data was collected from workshops and interviews and then analyzed. The conclusion of the research was that the participants perceived that the project had been worthwhile and was to be continued. The nature reserve is now more widely and usefully used
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Date Issued: 1996

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"Why I like history ...": Ciskeian secondary school pupils' attitudes towards history

- Atuahene-Sarpong, Boateng Kofi

Authors: Atuahene-Sarpong, Boateng Kofi
Date: 1993
Subjects: History -- Study and teaching (Secondary) -- South Africa--Ciskei -- Attitudes , History -- Study and teaching (Secondary) -- South Africa -- Ciskei
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1824 , http://hdl.handle.net/10962/d1003710 , History -- Study and teaching (Secondary) -- South Africa--Ciskei -- Attitudes , History -- Study and teaching (Secondary) -- South Africa -- Ciskei
Description: This dissertation was motivated by the decline in percentage of the number of Standard 10 pupils who offered History for the National Senior Certificate (Matriculation) Examination in the Mathole Directorate in the Ciskei from 1987 - 1990. The research revealed that the decrease in the number of pupils doing History in Standard 10 did not indicate loss of interest in the subject. Instead, the multiplicity of new subjects introduced in the school curriculum and some peculiar subject combinations in some schools forced some pupils (reluctantly) to reject History as a school subject. Those who chose to do History in Standard 10 showed their liking for the subject and expressed their interest in it. The study took the form of a survey through the use of questionnaire and informal chats with pupils and teachers on their views about History as a school subject. A questionnaire was designed for pupils offering History in Standard 10 and administered in four of the eight Senior Secondary Schools in the Mathole Directorate in Ciskei. Generally, work on pupils' interest in and attitude towards History as a school subject is very rare. Some of the few available works merely compare pupils' liking for History as opposed to other school subjects and when the response is not favourable; conclude that pupils in Senior Secondary Schools do not enjoy studying History. Pupils' interest in and attitudes towards the subject, the extent of their interest, the causes of their attitude and the internal and external influences on their interest in and attitudes towards the subject were neglected by earlier works, but have been given attention in this study. As a result of very little available work and material, pupils' responses to the questionnaire formed the basis of the material used in this work. A large number of pupils' responses was put in tables according to sex instead of schools. Where applicable, X2 tests were administered to see if there were any appreciable statistically significant differences between the responses of the boys and girls. In most cases where the X2 tests were applied, no statistically difference was noticed. The study showed more boys than girls showing interest in and positive attitudes towards History. The general picture of the study showed a deviation from the view commonly expressed by other studies that pupils in modern Senior Secondary Schools do not like History. As this study revealed, it is not the subject itself that pupils did not like, but the way it is handled by some teachers and lack of teaching aids to concretise events. This leads to the role of Teacher Training Institutions: which must be to produce the versatile, duty-conscious and innovating History teacher to revolutionise History teaching to make History alive to pupils.
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Date Issued: 1993

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Biological studies of insect herbivores associated with some species of Solanum L

- Olckers, Terence

Authors: Olckers, Terence
Date: 1989
Subjects: Solanum -- Control -- South Africa Phytophagous insects -- South Africa
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5593 , http://hdl.handle.net/10962/d1002043
Description: Solanum mauritianum Scop. (bugweed), a serious exotic weed in South Africa, supports a depauperate herbivore fauna relative to indigenous Solanum species. These comprise mainly polyphagous, and some oligophagous, species. The greater diversity of insect herbivores on Solanum hermannii Dun., relative to other indigenous Solanum species in the eastern Cape, suggests that the plant is indigenous and not exotic as has been suggested. Five oligophagous species seasonally caused a high incidence of damage to S.hermannii and other indigenous Solanum species in the eastern Cape, during the study period. Galls of the flowers, stems and leaves of some indigenous Solanum plants are described and biological data on the gall-formers and their natural enemies presented. The tortoise beetle, (Chrysomelidae), defoliates a Conchyloctenia tigrina wide range of indigenous Olivo Solanum species. The exotic S.mauritianum and S.elaeagnifolium Cav. were unfavourable for growth and survival. S.hermannii proved the most favourable of the indigenous hosts tested, for growth and survival, providing further evidence that it is indigenous. Extensive studies on different field populations of the beetle revealed no evidence of host adaptation (host races). All populations tested displayed greater fitness when reared on S.hermannii. South African Solanum faunas are characterized by a scarcity of endophagous and monophagous herbivores, vacant feeding niches and low numbers of species relative to other plant taxa. This may suggest evolutionary immaturity of the insect-plant associations, although comparative studies of solanums from other parts of the world are needed for confirmation. Alternatively, these characteristics may simply be a feature of the genus Solanum in general. The depauperate herbivore fauna of S.mauritianum reflects a lack of local herbivores suitably preadapted to overcome its defences. This appears to be accentuated by absence of any close relatives of bugweed in South Africa. The greater diversity of herbivores in its native South America suggests that biological control may be a potentially useful means of control for bugweed. The potential for biological control is, however, threatened by the susceptability of the cultivated eggplant (Solanum melongena L.) to attack by Solanum-feeding insects. Possible solutions to this problem are discussed
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Date Issued: 1989

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The survival of Heliothis Armiger (Hübner) (Lepidoptera: Noctuidae) eggs on cotton plants in relation to simulated rain and overhead irrigation

- Basson, Nicolaas Cornelius Johannes

Authors: Basson, Nicolaas Cornelius Johannes
Date: 1987
Subjects: Helicoverpa armigera Lepidoptera
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5598 , http://hdl.handle.net/10962/d1002048
Description: Crop pests are known to be adversely affected by rain. Because limited information on this aspect was available for Heliothis spp. occurring on cotton, this study was undertaken to examine the effect of water droplets from overhead irrigation and simulated rain on the survival of H. armiger eggs on cotton. Three aspects were examined: the effects of submersion, the physical impact of droplets on the eggs and the washing off of the eggs from cotton plants in the field. The first two aspects were examined in terms of the structure and respiratory system of the eggs, confirming that H. armiger eggs are able to survive initial wetting in the field. The wash-off of H. armiger eggs from cotton plants is explained in the light of the selection of oviposition sites by the moths, adhesion of the eggs to the plant parts and the dislodging and wash-off by water from simulated rain and overhead irrigation. The data are discussed in terms of the other mortality factors which occur in commercial cotton fields. All in all, it was found that while overhead irrigation should be taken into account in surveys of H. armiger for pest management purposes, it does not offer a viable control strategy and should not be investigated further
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Date Issued: 1987

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Skoolvoorligting in die primêreskool met spesifieke verwysing na druiping van intelligente leerlinge in Kaapland

- Maritz, Jacob Petrus

Authors: Maritz, Jacob Petrus
Date: 1985
Subjects: Counseling in elementary education -- South Africa--Western Cape , School failure -- South Africa -- Western Cape
Language: Afrikaans
Type: Thesis , Masters , MEd
Identifier: vital:1366 , http://hdl.handle.net/10962/d1001432 , Counseling in elementary education -- South Africa--Western Cape , School failure -- South Africa -- Western Cape
Description: Die doelstellings van onderwys in die primereskool maak o.a. voorsiening vir al die behoeftes van leerlinge. Om die doel te bereik is dit nood saaklik dat alle moontlike middele en dienste benut word. Skoolvoorligting maak 'n noodsaaklike deel uit van die spektrum van voorsiening. Skoolvoorligting is nie iets nuut wat van buite op die skool afgedruk word nie, maar vorm 'n integrale deel van gesonde onderwyspraktyk. Die gevaar bestaan dat skoolvoorligting sy invloed kan verloor ten koste van 'n meer a kademiesgerigte leerplan. In die lig hiervan is dit nodig om te bepaal wat die aard en doel van skoolvoorligting in die primereskool is (Introduction, p. 8)
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Date Issued: 1985

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The Hakea fruit weevil, Erytenna consputa Pascoe (Coleoptera: Curculionidae), and the biological control of Hakea sericea Schrader in South Africa

- Kluge, Robert Louis

Authors: Kluge, Robert Louis
Date: 1984
Subjects: Insects as biological pest control agents -- South Africa Biological pest control agents -- South Africa Beetles -- South Africa Curculionidae -- South Africa Weeds -- Biological control -- South Africa Pests -- Biological control -- South Africa
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5629 , http://hdl.handle.net/10962/d1004911
Description: Hakea sericea is a shrub, introduced into South Africa from southern Australia, that is now invading the indigenous "fynbos" vegetation in the Cape mountains. Presently an area of 480 000 hectares is affected. One of the main factors contributing to the success of H. sericea as a weed is its copious seed production. The seeds are accumulated on the plant throughout its life-time. When the plant eventually dies, usually after a fire, the fruits dehisce and all the seeds are released within the space of a few days, resulting in seed densities of up to 7 500 seeds per m². Dense, impenetrable stands of H. sericea develop which suppress the indigenous vegetation. Apart from the labour intensive mechanical clearing of H. sericea, biological control appears to be the only other means of control. This study deals with the post-release evaluation of the effectiveness of the first successfully-established, biological control agent, the hakea fruit weevil, Erytenna consputa. Most of the damage is done by the larval stage of the weevil which attacks the young developing fruits, thereby reducing seed production.
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Date Issued: 1984

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Mineralogy and petrology of two kimberlites at Dutoitspan Mine, Kimberley

- Snowden, D V

Authors: Snowden, D V
Date: 1981
Subjects: Kimberlite -- South Africa -- Kimberley , Mineralogy -- South Africa -- Kimberley , Petrology -- South Africa -- Kimberley
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4929 , http://hdl.handle.net/10962/d1004706
Description: The mineralogy and petrology of two kimberlites, a peripheral monticellite kimberlite, and its core of phlogopite kimberlite, from the West Auxiliary Pipe at Dutoitspan Mine are described. The mineralogy of the two kimberlites differs mainly in the presence of phlogopite macrocrysts, greater abundance of angular crustal inclusions, more heavy minerals and higher diamond grade in the phlogopite type. Microprobe analyses of olivine, phlogopite, monticellite, oxide minerals and garnet are presented. Silicate compositions are comparable in both kimberlites and zoning of olivine grains is typically towards a rim of Fo₈₉₋₉₀ʻ irrespective of whether cores are more Fe-rich or more Mg-rich. This is caused by re-equilibration after fluidised emplacement in the earth's crust of macrocryst-bearing kimberlite magma. Olivine aggregates were derived from sheared mantle lherzolite and single-crystal macrocrysts were formed at higher mantle levels from a kimberlitic crystal-mush magma. This was emplaced in the crust by rapid gas streaming. The post-fluidisation phenocrysts of olivine and phlogopite which formed then are in general more Fe-rich than macrocrysts. Re-equilibration of ilmenite results in the formation of complex perovskite and titanomagnetite mantles. Phlogopite macrocrysts are preserved in the monticellite contact rock where rapid quenching prevented their resorption and allowed separation of an immiscible carbonate melt, giving the abundant groundmass calcite. Atoll-textured spinels are found in the contact rock. Major and minor trace-element analyses of whole rock samples are presented and discussed, bringing into account the problem of contamination by crustal inclusions. Whole rock chemistry supports derivation of the kimberlites as partial melts of mantle material in the presence of a lithophile-element-enriched fluid. The monticellite contact rock is highly enriched in REE, Nb, and Sr due to rapid freezing of this perovskite-enriched phase. The monticellite type is more enriched in lithophile elements than the phlogopite type, which supports derivation of the monticellite type by a small degree of partial melting, further melting reducing the relative concentrations of lithophile elements to give the phlogopite kimberlite chemistry.
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Date Issued: 1981

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The study of the potentiation of anticholinergic side effects of tricyclic antidepressives by female sex steroids

- Kok, Eric Charl

Authors: Kok, Eric Charl
Date: 1981
Subjects: Antidepressants , Steroid hormones
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:3822 , http://hdl.handle.net/10962/d1005623 , Antidepressants , Steroid hormones
Description: It has been recorded that women respond to tricyclic antidepressives with a greater incidence of anticholinergic side effects than men do, particularly women taking an exogenous source of oestrogen. The aim of this study was to investigate the influence that ethinyl oestradiol and Premarin© had on the metabolism of a number of tricyclic antidepressives, and also the influence they had on the binding ability of microsomes to imipramine. Rat hepatocyctes and microsomes were used. Detection techniques used were High Pressure Liquid Chromatography and Spectrophotometry respectively. In addition to these studies, a study of the anticholinergic activity of Nomifensine, tricyclic antidepressives and their derivatives was performed on a rat jujenum. Results conclusively showed that ethinyl oestradiol had a marked influence on the metabolism of the tricyclic antidepressives studied. Premarin© had Iittle, if any influence. However, both ethinyl oestradiol and Premarin© affected the binding of microsomes to imipramine, but ethinyl oestradiol had the greater effect. The parent compound in each case exhibited a higher pAZ value. Results indicate that a possible explanation for the increased anticholinergic side effect is due to an inhibition of the metabolism of the tricyclic antidepressives by oestrogen.
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Date Issued: 1981

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The role of the artist in society as seen in the novels of Henry James

- Middleton, D F

Authors: Middleton, D F
Date: 1963
Subjects: James, Henry, 1843-1916 , Journalists as artists , Art and society , Fiction -- History and criticism -- 19th century
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2305 , http://hdl.handle.net/10962/d1012874
Description: Henry James (1843-1916) is a curious and, by his own choice, enigmatic figure. We have a great many dates, a few letters, and little else. James's fragment of autobiography, vast as it is; is strangely unrevealing. There is a wealth of impressions as one would expect from such a writer but precious little about the man. Henry James was chary of describing his personal feelings - so much so that some doubted his ability to have any strong emotions. His autobiography, interesting as it is, is pure observation, memories of people, places and impressions, all marvellously sensitive, but little personal feeling. Intro., p. 1.
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Date Issued: 1963

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