The adaptive development and use of learning support materials in response to the 1st principle of the revised national curriculum statement : the case of Hadeda Island
- Authors: Olvitt, Lausanne Laura
- Date: 2004
- Subjects: Environmental education -- South Africa -- Case studies Environmental education -- Curricula -- South Africa Teaching -- Aids and devices -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1938 , http://hdl.handle.net/10962/d1007719
- Description: This case study describes the development and trial use of the Hadeda Island Big Book. Developed within a transforming South African curriculum framework, the study recognises that current educational practices are shaped and steered by historical, cultural, political and economic realities. This perspective guides the research design, which considers each of the three participating schools as contextually unique. The Hadeda Island Big Book was developed in response to the 1st Principle of the Revised National Curriculum Statement (RNCS). This calls for all curriculum activities to develop learners' understandings of the relationship between social justice, a healthy environment, human rights and inclusivity. The study probes ways in which learning support materials might respond in line with the vision of the RNCS 1st Principle. Associated challenges, tensions and opportunities are discussed in relation to schools' interactions with the Hadeda Island Big Book. The diverse and creative responses to the book lead this study to foreground generative approaches to curriculum work. Emphasis is thus redirected from hierarchical, stipulative views of curriculum to more dynamic, responsive views of curriculum as a guiding framework. This is regarded as a valuable orientation to the development of future learning support materials. The study comments on the challenge of supporting teachers to develop curriculum activities that reflect a view of 'environment' as socially shaped and multi-dimensional. Tendencies to focus on either the 'ecological' or the 'social' dimensions of environmental issues rather than on the interacting socio-ecological dimensions are recognised as limiting the material's potential to strengthen environmental learning in schools. The study recommends that greater attention be paid to the environmentally-oriented Learning Outcomes and Assessment Standards of all Learning Areas in the RNCS. In so doing, socio-ecological learning processes may be strengthened through curriculum work.
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The development of a geographic information system (GIS) as a mariculture sector planning tool in South Africa
- Authors: Shiran-Klotz, Imran
- Date: 2004
- Subjects: Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5337 , http://hdl.handle.net/10962/d1005870 , Geographic information systems -- South Africa , Fishery management -- Geographic information systems -- South Africa , Mariculture -- South Africa
- Description: The South African coastline has a high potential for mariculture development, particularly in land-based systems, due to excellent water quality, good infrastructure, and relatively cheap land in certain areas. Development of mariculture however, has been slow primarily due to the absence of a national sector development plan to coordinate contribution to development by government, industry and academia. Recent mariculture development plans however, supported by government commitment to stimulate coastal development, offers new opportunity for the sector's growth. These new sector development plans require a multi-disciplinary intensive information base with a strong regional and national spatial component. Geographic Information System (GIS) is a spatial analytical tool, which is capable of handling such large coastal databases and analysing them. Nevertheless, many mariculture GIS planning applications, often developed in isolation and with limited practical use for decision makers, highlighted the need to develop GIS in relation to the mariculture sector development plan. Hence, the aim of this study was to develop and evaluate a GIS for the national and regional mariculture sector planning process in South Africa, in order to identify potentially suitable areas along the South African coastline for mariculture operations. The GIS development in this study was based on the mariculture planning approach developed by PAP/RAe (1996), which recognizes the variations of scales in mariculture planning. Three case studies, representing the diversity of the South African sector plan, were selected to develop the GIS. They included: a national suitability analysis for all land-based culture systems, a specific national analysis on abalone ranching, and a detailed regional analysis of land-based culture and abalone ranching along the Namaqualand coastline. The GIS was developed separately for each case study based on a strategy consisting of six main phases, including: identification of project requirements, developing analytical framework, selection and location of data sources, organization and manipulation of data, analysing data and verifying and evaluation of the outputs. Biophysical, coastal use, and infrastructure criteria were collected, sorted and analysed to identify development constraints. Based on a set of conditions, and Boolean logic and arithmetic operations, unsuitable areas were identified and eliminated. Main constraints for national land-based development included competition over space along KwaZuluNatal Province coastline and restricted access to the coast along the south region of the Northern Cape Province, Wild Coast along the Eastern Cape Province, and Maputaland along KwaZulu-Natal Province. Ten areas along the country coastline were therefore identified as potentially suitable for land-based mariculture. Furthermore, South African abalone ranching potential was found to be limited mostly along the Western and Northern Cape Province's coastline due to the high risk of Paralytic Shellfish Poison (PSP) occurrences, alternative resource use and activities such as commercial fishery, poaching, and conservation. Hence, a total of nine areas along the Northern Cape, Western Cape, and Eastern Cape coastlines were identified as premier areas for abalone ranching. The regional study along the Namaqualand coastline revealed potential conflict between mining activity and mariculture development due to security issues and restricted access to the coast. Land-based mariculture development was confined to the four main coastal urban areas. The highest potential for land-based mariculture was along Port Nolloth and Kleinsee coastlines, whereas marine-based (i.e. abalone ranching) potential was poor along the north part of the coast due to intense marine mining activities, restricted access to the coast, and low kelp bed density. High potential abalone ranching areas were identified south to Kleinsee, and around Port Nolloth. Potential conflict with marine mining activity was minimal since it was localised and not related to kelp bed locations. It was concluded that GIS is a relevant and compatible tool for South African mariculture sector planning. However, future development of GIS as integrated planning tool in mariculture and coastal planning, requires updated spatial data (e.g. recreational activity), and continued interaction among project planners, mariculture specialists and GIS analysts.
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The doctrine of duress in the law of contract and unjustified enrichment in South Africa
- Authors: Glover, Graham Brian
- Date: 2004
- Subjects: Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3672 , http://hdl.handle.net/10962/d1003187 , Contracts -- South Africa , Duress (Law) -- South Africa , Remedies (Law) -- South Africa
- Description: This thesis analyses the doctrine of duress and its application in the law of contract and unjustified enrichment in South Africa. Following an initial examination of the historical development of the doctrine from its roots in Roman and Roman-Dutch law, the study focuses on the current legal position in the two areas of law under review, identifies the substantive and formal deficiencies in the current approach, and suggests, using comparative authorities, how the law might be developed. As far as the law of contract is concerned, after exposing the difficulties inherent in the current approach, and placing the doctrine in its proper context in the South African law of contract generally, it is argued that the duress doctrine finds its juridical basis in the principle of good faith. A more modern and coherent test for duress is then proposed: one that concentrates on the question whether an illegitimate threat was made, which induced a contract in that it left the other person no reasonable choice but to succumb to the proposal. Additionally, the need for South African contract law to recognise and deal with cases of economic duress is emphasised. The study then shifts to an examination of the position in situations where non-contractual performances have occurred under duress: cases that are decided in terms of the principles of the law of unjustified enrichment. The current position is reviewed, and it is shown that the approach to duress cases is substantially different to the approach that applies in contract. An attempt is made to reconcile this problem. From a structural perspective, the nature and application of the relevant enrichment action where a non-contractual performance is made under duress (the condictio indebiti) is also investigated, in the light of approaches to enrichment adopted in both Germany and England, in an attempt to make better sense of this enrichment action in the South African context. The study closes with an analysis of the various contractual, delictual and enrichment remedies that are available once a case of duress has been proved.
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The ecology and control of small hive beetles (Aethina tumida Murray)
- Authors: Ellis, James Douglas
- Date: 2004
- Subjects: Bee culture , Bee culture -- United States , Nitidulidae , Beetles -- Ecology , Beetles -- Control
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5917 , http://hdl.handle.net/10962/d1016253
- Description: The small hive beetle (Aethina tumida Murray) is an endemic scavenger in colonies of honey bee (Apis mellifera L.) subspecies inhabiting sub-Saharan Africa. The beetle only occasionally damages host colonies in its native range and such damage is usually restricted to weakened/diseased colonies or is associated with after absconding events due to behavioral resistance mechanisms of its host. The beetle has recently been introduced into North America and Australia where populations of managed subspecies of European honey bees have proven highly susceptible to beetle depredation. Beetles are able to reproduce in large numbers in European colonies and their larvae weaken colonies by eating honey, pollen, and bee brood. Further, adult and larval defecation is thought to promote the fermentation of honey and large populations of beetles can cause European colonies to abscond, both resulting in additional colony damage. The economic losses attributed to the beetle since its introduction into the United States have been estimated in millions of US dollars. Although beetles feed on foodstuffs found within colonies, experiments in vitro show that they can also complete entire life cycles on fruit. Regardless, they reproduce best on diets of honey, pollen, and bee brood. After feeding, beetle larvae exit the colony and burrow into the ground where they pupate. Neither soil type nor density affects a beetle’s ability to successfully pupate. Instead, successful pupation appears to be closely tied to soil moisture. African subspecies of honey bees employ a complicated scheme of confinement (aggressive behavior toward and guarding of beetles) to limit beetle reproduction in a colony. Despite being confined away from food, adult beetles are able to solicit food and feed from the mouths of their honey bee guards. Remarkably, beetle-naïve European honey bees also confine beetles and this behavior is quantitatively similar to that in African bees. If confinement efforts fail, beetles access the combs where they feed and reproduce. Two modes of beetle oviposition in sealed bee brood have been identified. In the first mode, beetles bite holes in the cappings of cells and oviposit on the pupa contained within. In the second mode, beetles enter empty cells, bite a hole in the wall of the cell, and oviposit on the brood in the adjacent cell. Despite this, African bees detect and remove all of the infected brood (hygienic behavior). Similarly, European bees can detect and remove brood that has been oviposited on by beetles. Enhancing the removal rate of infected brood in European colonies through selective breeding may achieve genetic control of beetles. Additional avenues of control were tested for efficacy against beetles. Reducing colony entrances slowed beetle ingress but the efficacy of this method probably depends on other factors. Further, the mortality of beetle pupae was higher when contacting species of the fungus Aspergillus than when not, making biological control an option. Regardless, no control tested to date proved efficacious at the level needed by beekeepers so an integrated approach to controlling beetles remains preferred. The amalgamation of the data presented in this dissertation contributed to a discussion on the beetle’s ecological niche, ability to impact honey bee colonies in ways never considered, and the ability to predict the beetle’s spread and impact globally.
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The effect of commercialisation, privatisation and liberalisation on universal access in South Africa
- Authors: Gardner, Sean Patrick Newell
- Date: 2004
- Subjects: Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3431 , http://hdl.handle.net/10962/d1002885 , Telkom (Firm : South Africa) , Telecommunication , Telecommunication -- South Africa , Privatization -- South Africa , Trade regulation -- South Africa
- Description: From the 1990s onwards, significant developments have occurred in the international telecommunications sector that have affected the South African telecommunications industry and peoples’ access to the network. Rapid developments in Information and Communication Technologies and the reorganisation of telecommunications operators through commercialisation, privatisation and the effects of market liberalisation have resulted in monopoly operators moving away from their public service mandates. Globalisation and adherence to World Trade Organisation rules are causing operators to rebalance their tariffs closer to cost. Long-distance rates are decreasing while the cost of local calls is increasing. High-end users of telecommunications services are benefiting while low-end, largely residential users are being priced off the network. The end result is a negative effect on universal access to telecommunications services. This study examines the extent to which commercialisation, privatisation and liberalization are affecting the provision of telecommunications services and the government’s goal of achieving universal access in South Africa. Qualitative research methods were utilised to establish that the state owned operator, Telkom, has transformed itself from a public service operator to one that is fully commercialised and prepared for an Initial Public Offering and competition. Telkom no longer attempts to ensure that its tariffs are affordable for all people. However, positive developments presented themselves in the form of an increasingly competent regulator, a reorganised and dedicated Universal Service Agency, and the popularity of cellular telephony. The primary discovery of this study is that the liberalisation of the South African telecommunications sector cannot be assumed to have a negative effect on the provision of service. This study finds that liberalisation will most likely benefit the country through the role out of new infrastructure, the provision of new services and ultimately the reduction of those services themselves. In order for universal access to be achieved in this country the study recommends that the resources of the Independent Communications Authority of South Africa be enhanced to enable the regulator oversee the industry effectively. Secondly, the Universal Service Agency must provide clear definitions of universal access and universal service as well as manage the Universal Service Fund with greater efficiency. Lastly, the two bodies mentioned above must ensure that services are affordable for all people of this country.
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The effect of diet type and feeding rate on growth, morphological development and behaviour of larval and juvenile goldfish Carassius auratus (L.)
- Authors: Paulet, Timothy Guy
- Date: 2004
- Subjects: Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5271 , http://hdl.handle.net/10962/d1005115 , Goldfish -- Growth , Goldfish -- Nutrition , Goldfish -- Development , Goldfish -- Larvae
- Description: Intensive grow-out of goldfish, Carassius auratus (L.), larvae and juveniles in closed recirculating systems requires the control of environmental conditions and feeding. This study investigated the effect of different diets, environmental condition and feeding level on growth, development and survival of goldfish larvae and juveniles. Prey preference for Artemia nauplii or decapsulated Artemia cysts as well as agonistic behaviour was recorded. The micrometer device used to measure mouth-gape was shown to produce accurate measurements which could be used to estimate the maximal particle size that can be ingested by goldfish larvae of a particular age. Goldfish completed metamorphosis earlier with an increased feeding level of Artemia cysts and by making the cysts more accessible to the fish using up-welling water movement. Morphometric plasticity in goldfish larvae was exhibited within two weeks of growth and it may be possible to induce changes in morphology by manipulating diet and rearing environment. Fish that fed on moving prey items had a significantly larger mouth-gape than those that browsed cysts from the tank bottom or dry food items. The development of mouth-gape was not affected by the feeding level of cysts. Condition factor increased with an increase in the number of cysts fed per fish per day. Goldfish larvae and juveniles grew faster and had a higher survival when fed on decapsulated Artemia cysts than on instar I Artemia nauplii or a mixed live/dry diet of Artemia nauplii and dry food. Feeding at least 155 cysts per fish per day, in tanks with upwelling water movement, gave the best growth and survival and the smallest size variation. In addition, cysts remained available to the fish for longer periods, and were easier to prepare and feed. Goldfish larvae preferred decapsulated Artemia cysts to nauplii and rejected fewer prey items as they grew older. The frequency of agonistic behaviour increased as fish grew but no cannibalism was recorded for cyst-fed fish. This study showed that decapsulated Artemia cysts are a good alternative to Artemia nauplii as a diet for larval goldfish. Good growth and high survival was achieved for cyst-fed goldfish larvae and juveniles at 23 ± 1.5°C and at an initial stocking density of 12 fish per litre. This research also contributes to an understanding of feeding behaviour and attempts to minimise under- or over-feeding of Artemia cysts in order to reduce grow-out costs due to the high value of the feed type.
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The enzymology of enhanced hydrolysis within the biosulphidogenic recycling sludge bed reactor (RSBR)
- Authors: Enongene, Godlove Nkwelle
- Date: 2004
- Subjects: Hydrolysis , Sewage sludge , Sewage -- Purification -- Anaerobic treatment , Water -- Purification -- Biological treatment
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4132 , http://hdl.handle.net/10962/d1015744
- Description: The hydrolysis of complex organic heteropolymers contained in municipal wastewater to simpler monomers by extracellular hydrolytic enzymes is generally considered the rate-limiting step of the biodegradation process. Previous studies of the Recycling Sludge Bed Reactor (RSBR) revealed that the hydrolysis of complex particulate organics, such as those contained in primary sludge (PS), was enhanced under anaerobic biosulphidogenic conditions. Although the mechanism was not fully understood, it appeared to involve the interaction of sulfide and sludge flocs. The current study was conducted using a 3500 ml laboratory-scale RSBR fed sieved PS at a loading rate of 0.5 kg COD/m³.day and an initial chemical oxygen demand (COD) to sulfate ratio (COD:SO₄) of 1:1. There was no significant accumulation of undigested sludge in the reactor over the 60-day experimental period and the quantity of SO₄ reduced indicated that the yield of soluble products from PS was at least as high as those reported previously for this system (> 50%). In the current study, the specific activities of a range of extracellular hydrolytic enzymes (L-alanine aminopeptidase, L-leucine aminopeptidase, arylsulphatase, α-glucosidase, β- glucosidase, protease and lipase) were monitored in a sulfide gradient within a biosulphidogenic RSBR. Data obtained indicated that the specific enzymatic activities increased with the depth of the RSBR and also correlated with a number of the physicochemical parameters including sulfide, alkalinity and sulfate. The activities of α- glucosidase and β-glucosidase were higher than that of the other enzymes studied. Lipase activity was relatively low and studies conducted on the enzyme-enzyme interaction using specific enzyme inhibitors indicated that lipases were probably being digested by the proteases. Further studies to determine the impact of sulfide on the enzymes, showed an increase in the enzyme activity with increasing sulfide concentration. Possible direct affects were investigated by looking for changes in the Michaelis constant (Km) and the maximal velocity (Vmax) of the crude enzymes with varying sulfide concentrations (250, 400 and 500 mg/l) using natural and synthetic substrates. The results showed no significant difference in both the Km and the Vmax for any of the hydrolytic enzymes except for the protease. The latter showed a statistically significant increase in the Km with increasing sulfide concentration. Although this indicated a direct interaction, this difference was not large enough to be of biochemical significance and was consequently not solely responsible for the enhanced hydrolysis observed in the RSBR. Investigation into the floc characteristics indicated that the biosulphidogenic RSBR flocs were generally small in size and became more dendritic with the depth of the RSBR. Based on the above data, the previously proposed descriptive models of enhanced hydrolysis of particulate organic matter in a biosulphidogenic RSBR has been revised. It is thought that the effect of sulfide on the hydrolysis step is primarily indirect and that the reduction in floc size and alteration of the floc shape to a more dendritic form is central to the success of the process.
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The enzymology of sludge solubilisation under biosulphidogenic conditions : isolation, characterisation and partial purification of endoglucanases
- Authors: Oyekola, Oluwaseun Oyekanmi
- Date: 2004
- Subjects: Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3921 , http://hdl.handle.net/10962/d1003980 , Sewage -- Purification -- Anaerobic treatment , Anaerobic bacteria , Sewage sludge , Hydrolysis
- Description: Endoglucanases play an important function in cellulose hydrolysis and catalyse the initial attack on the polymer by randomly hydrolysing the β-1,4 glucosidic bonds within the amorphous regions of cellulose chains. Cellulolytic bacteria have been isolated and characterised from the sewage sludge and the activation of several hydrolytic enzymes under biosulphidogenic conditions of sewage hydrolysis has been reported. The aims of this study were to: identify, induce production, locate and isolate, characterise (physicochemical and kinetic) and purify endoglucanases from anaerobic biosulphidogenic sludge. The endoglucanase activities were shown to be associated with the pellet particulate matter and exhibited a pH optimum of 6 and temperature optimum of 50 °C. The enzymes were thermally more stable when immobilised to the floc matrix of the sludge than when they were released into the aqueous solution via sonication. For both immobilised and released enzymes, sulphate was slightly inhibitory; activity was reduced to 84 % and 77.5 % of the initial activity at sulphate concentrations between 200 and 1000 mg/l, respectively. Sulphite was stimulatory to the immobilised enzymes between 200 and 1000 mg/l. Sulphide stimulated the activities of the immobilised endoglucanases, but inhibited activities of the soluble enzymes above 200 mg/l. The enzyme fraction did not hydrolyse avicel (a crystalline substrate), indicating the absence of any exocellulase activity. For CMC (carboxymethylcellulose) and HEC (hydroxylethylcellulose) the enzyme had K_m,app_ values of 4 and 5.1 mg/ml respectively and V_max,app_ values of 0.297 and 0.185 μmol/min/ml respectively. Divalent ions (Cu²⁺, Ni²⁺ and Zn²⁺) proved to be inhibitory while Fe²⁺, Mg²⁺ and Ca²⁺ stimulated the enzyme at concentrations between 200 and 1000 mg/l. All the volatile fatty acids studied (acetic acid, butyric acid, propionic acid and valeric acid) inhibited the enzymes, with acetic acid eliciting the highest degree of inhibition. Sonication released ~74.9 % of the total enzyme activities into solution and this was partially purified by PEG 20 000 concentration followed by DEAE-Cellulose ion exchange chromatography, which resulted in an appreciable purity as measured by the purification factor, 25.4 fold.
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The experiences and needs of HIV/AIDS counsellors at Settlers Hospital, Grahamstown
- Authors: Nulty, Maria
- Date: 2004
- Subjects: AIDS (Disease) -- Patients -- Counseling of -- South Africa -- Eastern Cape HIV-positive persons -- Counseling of -- South Africa -- Eastern Cape Counselors -- South Africa -- Eastern Cape Counselors -- Supervision of -- South Africa -- Eastern Cape Counselors -- Training of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3032 , http://hdl.handle.net/10962/d1002541
- Description: Cognisant of the fact that counselling has become an essential aspect of dealing with HIV/AIDS in South Africa, the researcher aimed to explore the stressors experienced by HIV/AIDS counsellors. It was envisioned that the results obtained would both help to improve the counselling services provided at Settlers Hospital, and assist other organisations to do so. The research focused on how the participants dealt with the dual roles of non-directive listening and the more prescriptive advice-giving, the stressors they experienced and the support structures they had, or needed, to assist them in being more effective HIV/AIDS counsellors. The sample consisted of four HIV/AIDS counsellors working at Settlers Hospital, Grahamstown. The co-ordinator of HIV/AIDS at the hospital was interviewed for collateral information. A qualitative, multiple case study was undertaken. In-depth, semi-structured interviews were used to collect the data which were recorded and transcribed and then constructed into coherently organised personal narratives of each participant’s experiences. A composite description of all the results was arrived at through the use of a reading guide which reduced the data into a thematic content analysis. The analysed data served to present an understanding of the counsellors’ experiences and to enable recommendations to be made which could assist them in pursuing their work more effectively. The findings of this study indicate that HIV/AIDS counselling is an emotionally stressful occupation. Contributory factors include the twofold role of promoting prevention and serving as empathic listeners. Other stressors derive from issues of confidentiality and stigma concerning HIV/AIDS, counsellors’ identification with clients’ experiences and the demographics of HIV/AIDS in South Africa. Situational stressors which arise from working as both nurses and counsellors in a public health institution were also identified. Recommendations are made to alleviate the counsellors’ stress in the form of facilitated emotional support groups, professional supervision, managerial support to improve the working environment, and ongoing in-service training.
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The feeding biology and potential impact of introduced giraffe (Giraffa camelopardalis) in the Eastern Cape Province, South Africa
- Authors: Parker, Daniel Matthew
- Date: 2004
- Subjects: Giraffe -- South Africa -- Eastern Cape , Animal-plant relationships -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5694 , http://hdl.handle.net/10962/d1005380
- Description: Giraffe (Giraffa camelopardalis) are extralimital (non-native) to the Eastern Cape Province, South Africa yet they have and continue to be introduced to the region. Financial gain has arguably been the driving force behind these introductions as foreign tourists associate giraffe with Africa and the African wildlife experience. This raises a number of ethical, ecological and philosophical questions especially when it is considered that the impact of these browsers on the indigenous vegetation has remained largely unquantified. In this study I assessed the diet and potential impact of three populations of giraffe in the Eastern Cape Province between January 2002 and October 2003. The diet was assessed by both direct observations and faecal analysis. There was no significant difference (P > 0.05) between the results of the two methods of analysis, although direct observations appeared to be a superior method for assessing the diet of giraffe. The diet of giraffe in the Eastern Cape Province was similar to that within their native range with a deciduous species from the genus Acacia (Acacia karroo) being the most important component of the diet. However, giraffe in the Eastern Cape Province consumed more evergreen plant species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a likely explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident and this was attributed to the deciduous nature of A. karroo and the seasonal growth of new shoots which were more palatable. The vegetation of the areas most commonly utilised by giraffe at each site was sampled using the point-centred-quarter method and the results related to the frequency of each species in the diet to calculate preference indices. Giraffe preference was strongest for A. karroo and this was attributed to the highly favourable chemical composition of the species. The browse utilisation of giraffe at each site was determined using the twig-length method and intake rates for the three most important species in the diet calculated using a pre-existing regression equation. Male giraffe fed at a higher rate than females. This was probably due to males adopting a “time-minimising” strategy to their feeding in order to allow more time for reproductive pursuits. Giraffe browse utilisation was highest where giraffe density was highest. However, several species were more heavily browsed than others even when giraffe density was low, suggesting that giraffe are capable of negatively affecting the indigenous flora of the province. I conclude that giraffe numbers should be reduced relative to property size in the Eastern Cape Province and that research into the impact of not only giraffe but the combined effects of giraffe and other extralimital herbivores on the indigenous flora and fauna be continued.
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The geology of the Proterozoic Haveri Au-Cu deposit, Southern Finland
- Authors: Strauss, Toby Anthony Lavery
- Date: 2004
- Subjects: Geology, Stratigraphic -- Precambrian , Geology, Stratigraphic -- Proterozoic , Ore deposits -- Finland , Geology -- Finland
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5081 , http://hdl.handle.net/10962/d1015978
- Description: The Haveri Au-Cu deposit is located in southern Finland about 175 km north of Helsinki. It occurs on the northern edge of the continental island arc-type, volcano-sedimentary Tampere Schist Belt (TSB) within the Palaeoproterozoic Svecofennian Domain (2.0 – 1.75 Ga) of the Fennoscandian Shield. The 1.99 Ga Haveri Formation forms the base of the supracrustal stratigraphy consisting of metavolcanic pillow lavas and breccias passing upwards into intercalated metatuffs and metatuffites. There is a continuous gradation upwards from the predominantly volcaniclastic Haveri Formation into the overlying epiclastic meta-greywackes of the Osara Formation. The Haveri deposit is hosted in this contact zone. This supracrustal sequence has been intruded concordantly by quartz-feldspar porphyries. Approximately 1.89 Ga ago, high crustal heat flow led to the generation and emplacement of voluminous synkinematic, I-type, magnetite-series granitoids of the Central Finland Granitoid Complex (CFGC), resulting in coeval high-T/low-P metamorphism (hornfelsic textures), and D₁ deformation. During the crystallisation and cooling of the granitoids, a magmatic-dominated hydrothermal system caused extensive hydrothermal alteration and Cu-Au mineralisation through the late-D₁ to early-D₂ deformation. Initially, a pre-ore Na-Ca alteration phase caused albitisation of the host rock. This was closely followed by strong Ca-Fe alteration, responsible for widespread amphibolitisation and quartz veining and associated with abundant pyrrhotite, magnetite, chalcopyrite and gold mineralisation. More localised calcic-skarn alteration is also present as zoned garnetpyroxene- epidote skarn assemblages with associated pyrrhotite and minor sphalerite, centred on quartzcalcite± scapolite veinlets. Post-ore alteration includes an evolution to more K-rich alteration (biotitisation). Late D₂-retrograde chlorite began to replace the earlier high-T assemblage. Late emanations (post-D₂ and pre-D₃) from the cooling granitoids, under lower temperatures and oxidising conditions, are represented by carbonate-barite veins and epidote veinlets. Later, narrow dolerite dykes were emplaced followed by a weak D₃ deformation, resulting in shearing and structural reactivation along the carbonate-barite bands. This phase was accompanied by pyrite deposition. Both sulphides and oxides are common at Haveri, with ore types varying from massive sulphide and/or magnetite, to networks of veinlets and disseminations of oxides and/or sulphides. Cataclastites, consisting of deformed, brecciated bands of sulphide, with rounded and angular clasts of quartz vein material and altered host-rock are an economically important ore type. Ore minerals are principally pyrrhotite, magnetite and chalcopyrite with lesser amounts of pyrite, molybdenite and sphalerite. There is a general progression from early magnetite, through pyrrhotite to pyrite indicating increasing sulphidation with time. Gold is typically found as free gold within quartz veins and within intense zones of amphibolitisation. Considerable gold is also found in the cataclastite ore type either as invisible gold within the sulphides and/or as free gold within the breccia fragments. The unaltered amphibolites of the Haveri Formation can be classified as medium-K basalts of the tholeiitic trend. Trace and REE support an interpretation of formation in a back-arc basin setting. The unaltered porphyritic rocks are calc-alkaline dacites, and are interpreted, along with the granitoids as having an arc-type origin. This is consistent with the evolution from an initial back-arc basin, through a period of passive margin and/or fore-arc deposition represented by the Osara Formation greywackes and the basal stratigraphy of the TSB, prior to the onset of arc-related volcanic activity characteristic of the TSB and the Svecofennian proper. Using a combination of petrogenetic grids, mineral compositions (garnet-biotite and hornblendeplagioclase thermometers) and oxygen isotope thermometry, peak metamorphism can be constrained to a maximum of approximately 600 °C and 1.5 kbars pressure. Furthermore, the petrogenetic grids indicate that the REDOX conditions can be constrained at 600°C to log f(O₂) values of approximately - 21.0 to -26.0 and -14.5 to -17.5 for the metasedimentary rocks and mafic metavolcanic rocks respectively, thus indicating the presence of a significant REDOX boundary. Amphibole compositions from the Ca-Fe alteration phase (amphibolitisation) indicate iron enrichment with increasing alteration corresponding to higher temperatures of formation. Oxygen isotope studies combined with limited fluid inclusion studies indicate that the Ca-Fe alteration and associated quartz veins formed at high temperatures (530 – 610°C) from low CO₂, low- to moderately saline (<10 eq. wt% NaCl), magmatic-dominated fluids. Fluid inclusion decrepitation textures in the quartz veins suggest isobaric decompression. This is compatible with formation in high-T/low-P environments such as contact aureoles and island arcs. The calcic-skarn assemblage, combined with phase equilibria and sphalerite geothermometry, are indicative of formation at high temperatures (500 – 600 °C) from fluids with higher CO₂ contents and more saline compositions than those responsible for the Fe-Ca alteration. Limited fluid inclusion studies have identified hypersaline inclusions in secondary inclusion trails within quartz. The presence of calcite and scapolite also support formation from CO₂-rich saline fluids. It is suggested that the calcic-skarn alteration and the amphibolitisation evolved from the same fluids, and that P-T changes led to fluid unmixing resulting in two fluid types responsible for the observed alteration variations. Chlorite geothermometry on retrograde chlorite indicates temperatures of 309 – 368 °C. As chlorite represents the latest hydrothermal event, this can be taken as a lower temperature limit for hydrothermal alteration and mineralisation at Haveri.The gold mineralisation at Haveri is related primarily to the Ca-Fe alteration. Under such P-T-X conditions gold was transported as chloride complexes. Ore was localised by a combination of structural controls (shears and folds) and REDOX reactions along the boundary between the oxidised metavolcanics and the reduced metasediments. In addition, fluid unmixing caused an increase in pH, and thus further augmented the precipitation of Cu and Au. During the late D₂-event, temperatures fell below 400 °C, and fluids may have remobilised Au and Cu as bisulphide complexes into the shearcontrolled cataclastites and massive sulphides. The Haveri deposit has many similarities with ore deposit models that include orogenic lode-gold deposits, certain Au-skarn deposits and Fe-oxide Cu-Au deposits. However, many characteristics of the Haveri deposit, including tectonic setting, host lithologies, alteration types, proximity to I-type granitoids and P-T-X conditions of formation, compare favourably with other Early Proterozoic deposits within the TSB and Fennoscandia, as well as many of the deposits in the Cloncurry district of Australia. Consequently, the Haveri deposit can be seen to represent a high-T, Ca-rich member of the recently recognised Fe-oxide Cu-Au group of deposits.
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The Harry Potter phenomenon literary production, generic traditions, and the question of values
- Authors: Glover, Jayne Ashleigh
- Date: 2004
- Subjects: Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2201 , http://hdl.handle.net/10962/d1002243 , Rowling, J. K. Criticism and interpretation , Potter, Harry (Fictitious character) , Children's literature -- History and criticism , Fantasy fiction, English -- History and criticism , Wizards in literature
- Description: This thesis is a study of the first four books of J. K. Rowling’s Harry Potter series. It accounts for the widespread success of the novels by examining their publication and marketing histories, and their literary achievement as narratives including a sophisticated mix of generic traditions. Chapter One looks at the popularity of the novels, comparing their material production and marketing by Rowling’s English language publishers: Bloomsbury in Britain and Scholastic in the United States of America. The publisher’s influence on the public perception of each book is demonstrated by comparative study of its mode of illustration and layout. Further, the design of the books is linked to their strategic marketing and branding within the literary world. The second chapter considers Rowling’s debt to the school story. It concentrates first on the history of this relatively short-lived genre, briefly discussing its stereotypical features and values. Traditional elements of setting and characterisation are then examined to show how the Harry Potter novels present a value system which, though apparently old-fashioned, still has an ethical standpoint designed to appeal to the modern reader. Chapter Three focuses on the characterisation of Harry as a hero-figure, especially on how the influence of classical and medieval texts infuses Rowling’s portrayal of Harry as a hero in the chivalric mode. The episodes of “quest” and “test” in each book illustrate specifically how he learns the values of selflessness, loyalty, mercy and fairness. Chapter Four surveys the contribution of modern fantasy writing to the series. It shows how Rowling creates a secondary world that allows us to perceive magic as a metaphorical representation of power. This focus on the relationship between magic and power in turn has a bearing on our assessment of the author’s moral stance. The thesis concludes by suggesting that Rowling’s unusual mix of genres is justified by the values they share, and which are inscribed in her work: the generic combination forms a workable, new and exciting mode of writing that helps to account for the phenomenal popularity of the series.
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The impact of smart cards on South African rural pensioners' lives
- Authors: Nyoka, Zanele
- Date: 2004
- Subjects: Old age pensioners -- South Africa -- Management Smart cards South African Post Office
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:818 , http://hdl.handle.net/10962/d1008052
- Description: E-commerce technologies have many possible applications both in commercial and non-commercial operations. The development and implementation of these applications is on the increase especially by government and its agencies, for the delivery of services. Specific to this study is the distribution of old age pension benefits to recipients that reside in the rural areas of South Africa. Of importance to this study are the factors that promote and impinge on the development, implementation and acceptance of these applications. A specific project, the Pension Biometric Project was implemented by the South African Post Office in line with the government's initiatives of improving service delivery, and in response to the encroaching digital economy. The research problem is to investigate the pensioners' perception and their experience of three areas of this project, its implementation, its acceptance and its uses and impact. The research was conducted in the constructivist paradigm, using the case study research method. Three data collection methods were used, i.e. a document study of SAPO project documentation, on-site observations and interviews with pensioners. It was found that despite problems in implementation, the pensioners were accepting of the new system, although they were ignorant of the functionalities of the smart card. Consequently, few pensioners were making use of the banking facilities of the card, or had changed their economic behaviour. The study has also found that two themes are overriding all findings of the study. These two themes are ignorance and dignity. Ignorance has had a causal effect on adoption of the smart cards and dignity has been found to be a result of the project. The overriding implication of this study is that pensioners' ignorance around issues of service delivery by government and its agencies needs to be eradicated, otherwise there is no reliable way of measuring efforts against actual delivery. Also, the fact that dignity has emerged as an overriding theme needs to be deliberately strengthened, and maybe even driven as a specified objective of the Pension Biometric Project. Recommendations in this regard are provided as well as ideas for further research.
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The implementation of multigrade teaching in rural schools in the Keetmanshoop education region: leadership and management challenges
- Authors: Titus, David Petrus
- Date: 2004
- Subjects: Education -- Namibia Education, Rural -- Namibia Education and state -- Namibia Educational change -- Namibia School management and organization -- Namibia Rural schools -- Namibia Educational leadership -- Namibia School principals -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1566 , http://hdl.handle.net/10962/d1003448
- Description: Leadership has received much attention in both the business world and education. My thesis explores effective educational leadership through examining the management and leadership challenges that face principals in a multi-grade school. Schools in sparsely populated rural areas in Namibia have had to resort to multi-grade teaching to be able to be economically viable. Hard economic realities force people to move to bigger towns and cities. The constant demand for better schools, effective principals, qualified teachers and an improved service to the communities coupled with the demand for better working conditions and salaries for teachers drained the education budget even further. To keep in line with the four major policies of education namely equity, access, quality and democracy, the operation of smaller, rural multi-grade schools has become a necessity. The alternative – which is to close smaller schools and operate fewer, bigger schools at an affordable and reasonable cost - would deny rural communities access to schooling. This thesis is a case study of the leadership and management challenges of multigrade schooling in a single school. The goal was to understand how education managers and leaders perceived their role in making it possible for teachers and learners to cope with multi-grade teaching. I worked in the interpretive paradigm to be able to interpret the social and cultural context of a rural, multi-grade school in the Karas region. The methods included questionnaires, interviews and observation. One of the leadership models universally considered to be available to principals of multi-grade schools is instructional leadership. My study revealed that the concept was unknown to teaching staff, although there were indications that the model had been encountered. My findings also revealed that the communication between colleges of education and the regional education department staff was very limited. One of the major issues that arose was that principals were so occupied with teaching that important issues about training/evaluation and supervision of teachers, the ‘visibility’ of the principal, setting and implementation of the aims and goals of the school and regular communication with parents and community leaders were neglected. Probably the most significant finding was that head teachers are not trained in the management of a multi-grade school, hence most if not all of the head teachers run multi-grade schools like a single-graded school. The single most important problem was that the importance of multi-grade teaching had never been highlighted, particularly in light of new staffing norms, in spite of the fact that it was a phenomenon that was likely to be a permanent arrangement.
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The location of meaning in the postmodernist literary text: a reading of Mark Z. Danielewski's House of Leaves and related material
- Authors: Jeffery, Thomas Carnegie
- Date: 2004
- Subjects: Danielewski, Mark Z. House of leaves , Danielewski, Mark Z. Criticism and interpretation , Horror tales , English literature -- Criticism, Textual , Literature, Modern -- History and criticism , Postmodernism (Literature)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2196 , http://hdl.handle.net/10962/d1002238
- Description: In House of Leaves, Mark Z. Danielewski has produced a text which epitomises the traits and concerns of postmodernist literature. Through his attention to aspects such as metafiction, intertextuality and parody, Danielewski develops a narrative structure which is best understood as a literary labyrinth. It is a structure intended to reflect the social conditions of the twenty-first century and comment on the experience of people living at this time. Some of the meaning-making strategies within the book’s labyrinthine structure are thus discussed in detail in order to demonstrate the relevance and importance of House of Leaves as social commentary. House of Leaves is an exemplary postmodernist text, but it is also one that seeks to guide the reader beyond the intellectual impasse of the postmodernist paradigm toward a renewed ethical and political engagement with the world. One of the most important goals of both Danielewski’s novel and this thesis is to attempt to redefine the postmodernist perspective in such a way as to insist on the necessity of what I call a new realism. This is founded upon an awareness of the pervasiveness of the self-perpetuating ideology of capitalism, even in the perspective of postmodernism (which purports to subvert all authoritative ideologies). Playing a crucial role in perpetuating the status quo of capitalism is the growth of entertainment culture, which works to sideline crucial political issues by replacing information with infotainment. The result is an intensification of the processes of commodification. Such an intensification, it is argued, may be countered by a radical scepticism which draws upon the methods and insights of contemporary science.
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The market efficiency hypothesis and the behaviour of stock returns on the JSE securities exchange
- Authors: Mabhunu, Mind
- Date: 2004
- Subjects: Johannesburg Stock Exchange , Stocks -- Prices -- South Africa , Stock exchanges -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1027 , http://hdl.handle.net/10962/d1002762 , Johannesburg Stock Exchange , Stocks -- Prices -- South Africa , Stock exchanges -- South Africa
- Description: While the Efficient Market Hypothesis (EHM) has been widely accepted as robust by many researchers in the field of capital markets, the hypothesis’ robustness has been under increased scrutiny and question lately. In the light of the concerns over the robustness of the EMH, the weak form efficiency of the JSE is tested. Stock returns used in the analysis were controlled for thin trading and it was discovered that once returns are controlled for thin trading, they are independent of each other across time. Some of the previous studies found the JSE to be inefficient in the weak form but this research found that the JSE is efficient in the weak form. A comparison is also made between the JSE and four other African stock markets and the JSE is found to be more efficient than the other markets. The developments on the JSE, which have improved information dissemination as well as the efficiency of trading, contributed to the improvement of the JSE’s efficiency. The improvement in operational efficiency and turnover from the late 1990s has also made a major contribution to the improvement in the weak form efficiency of the JSE. Theory proposes that if markets are efficient then professional investment management is of little value if any; hence the position of professional investment managers in efficient markets is investigated. Although the JSE is found to be efficient, at least in the weak form, it is argued that achieving efficiency does not necessarily make the investment manager’s role obsolete. Investment managers are needed even when the market can be proved to be efficient.
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The mentally retarded offender in a forensic setting: a South African study
- Authors: Solomons, Warren Stanley
- Date: 2004
- Subjects: Mentally ill offenders -- South Africa , Forensic psychology , People with mental disabilities and crime -- South Africa , People with mental disabilities -- Rehabilitation , Mental health laws -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3063 , http://hdl.handle.net/10962/d1002572 , Mentally ill offenders -- South Africa , Forensic psychology , People with mental disabilities and crime -- South Africa , People with mental disabilities -- Rehabilitation , Mental health laws -- South Africa
- Description: This study examined, within the South African context, the prevalence of mental retardation in a forensic observation setting, and the impediments of and successes to forensic rehabilitation. The results of the study indicated that a significant amount of forensic observation patients (25.16%) are ultimately diagnosed as being mentally retarded, with 39.24 percent of such offenders being found unfit to plead. Further 32.91 percent of the same sample was found to be not responsible for their actions. A link was also drawn between the mentally retarded offender and violent offenses. The advantages and disadvantages of a current rehabilitative process are discussed in light of alternate community-based forms of rehabilitation that are being implemented in other countries, for example the United States of America, with a view towards investigated their usefulness and adaptability to South African circumstances. The findings of the study have implications for mental health professionals working within forensic settings concerning the future management of mentally retarded offenders, particularly within the rehabilitative process .
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The new economic geography of SADC free trade area
- Authors: Hess, Simon Peter
- Date: 2004
- Subjects: Southern African Development Community Free trade -- Africa, Southern Economic geography Industries -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:932 , http://hdl.handle.net/10962/d1001648
- Description: The current implementation of a free trade area in SADC has given rise to concerns that the present location of industry in the region will be adversely affected. Specifically, many of the smaller and less-developed countries fear that this change will result in a loss of their industry towards the more developed members, and particularly towards South Africa. This study uses the framework of the new economic geography to address these concerns. The new economic geography is a body of theory that has arisen in the last decade and allows for a dynamic analysis of the process of regional integration. Studies of such dynamic effects in the developing country context are exceedingly scarce, and particularly so in southern Africa. Another area of little research is in the comparison of the evolving industrial structure of different regional blocs. Thus, in response to this gap in the literature and in order to address the concerns of polarisation of industry within the SADC region, a two-pronged empirical approach is taken. The study first conducts a review of the spatial distribution of industry within SADC from 1970 to 1999. This is achieved through the calculation and examination of industrial locational Gini coefficients, measuring the relative degree of concentration of 28 ISIC (rev 2) industries for the years 1970, 1980, 1985, 1990, 1995 and 1999. Secondly, an empirical comparison is conducted with other blocs that are in the process of deepening regional integration, namely the European Union and Mercosur. Again, this is done through the calculation of locational Gini coefficients for individual industries for all three blocs at five year intervals from 1980 to 1995, and then for 1999. The average level of concentration within SADC is found to increase steadily from 1970 to 1990. Between 1990 and 1995, the level of concentration increases further, but at a lower rate, and, by 1999 industry begins to disperse. The Gini coefficient is a relative measure, and thus does not measure the absolute level of concentration. Thus, much of the increase in concentration seen is towards peripheral countries. To further interpret the Gini, the changes in concentration are compared to the absolute changes in manufacturing employment in South Africa. From this analysis, eight of the 28 industries analysed show particular tendencies to concentrate in the periphery. These are beverages, textiles, wearing apparel, paper and products, rubber products, other non-metallic mineral products, transport equipment, and professional and scientific equipment. Likewise, another six industries become more concentrated in South Africa over this time, namely food products, printing and publishing, industrial chemicals, petroleum refineries, miscellaneous petroleum and coal products, and electrical machinery. According to the Gini coefficient, the tobacco industry is by far the most concentrated, while the wood products industry is the most dispersed. It is also found that scale-intensive industries tend to be among the most concentrated. In the cross-bloc comparison, Mercosur has the lowest level of aggregate concentration with an average Gini of 0.08 in 1999. This compares with Ginis of 0.28 for the EU, and 0.22 for SADC. The EU has the largest increase in concentration over the period, while the concentration in Mercosur falls during the 1980s, increases in the mid 1990s and then falls again by 1999. A common theme, however, between all three blocs is a trend towards dispersion in the late 1990s. This is particularly apparent in SADC and Mercosur where the Gini decreases in value, while in the EU, the Gini only increases marginally in this period. Other studies of the EU have indicated that industry was starting to disperse at this time. This finding would be more apparent at a greater level of industrial disaggregation. The following industries are found to be agglomerated above the average level in all three blocs: tobacco, miscellaneous petroleum and coal products, and pottery china and earthenware. Conversely, transport equipment, paper and products, machinery except electrical, plastic products, rubber products, and fabricated metal products tend to be more dispersed across all three. Perhaps more interesting is that there appears to be some commonality between industries that become more agglomerated across all three blocs, while industries that dispersed tend to be region specific. The industries that show universal agglomeration tendencies are the highly sensitive wearing apparel and textiles industries, in addition to industrial chemicals, printing and publishing, iron and steel, and plastic products. In relation to SADC, the first two of these industries show an increased concentration in the periphery, as in the EU, while the remaining industries show tendencies to concentrate in the core. The new economic geography predicts that, as the presently high levels of transport costs begin to fall in SADC, industry will tend to concentrate in the core. However, the results of this study indicate that the effect on manufacturing is, to a large extent, sector specific, with some manufacturing industries concentrating in the core and others in the periphery. The study therefore concludes that the mass polarization of industry from the smaller countries in SADC towards South Africa is unlikely to occur with the further reduction in trade costs. Although certain industries may be attracted towards the core, the high degree of wage disparity in the region and present trade concessions from developed markets overseas towards the peripheral countries, will make these countries an attractive location, particularly for export orientated firms. Two main policy recommendations result from the study. Firstly, individual countries in SADC need to promote those industries that show concentration tendencies in their country. Secondly, in order for the periphery to maximize their gain from the free trade area, transport costs within the region need to be reduced rapidly and effectively.
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The occurrence of Nosema apis (Zander), Acarapis woodi (Rennie), and the Cape problem bee in the summer rainfall region of South Africa
- Authors: Swart, Dawid Johannes
- Date: 2004
- Subjects: Nosema apis , Bee culture , Honeybee -- South Africa , Honeybee -- Diseases , Honeybee -- Parasites , Mites
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5914 , http://hdl.handle.net/10962/d1015980
- Description: The occurrence of Nosema disease, tracheal mites and the “pseudo-parasitic” behaviour of Cape honeybee workers when placed amongst African honeybees – known as the Cape Bee Problem – were studied over a 18 month period. Three surveys, approximately 6 months apart were done. The aims of this study were to establish the distribution and severity of the diseases and compare the disease with the presence of the Cape Bee Problem. Before this survey commenced European Foul Brood disease, Sacbrood (virus), Nosema, Brood nosema, and Tracheal mite have sporadically been reported in the summer rainfall region of South Africa. In the first survey 1005 colonies in 61 apiaries were surveyed, 803 colonies in 57 apiaries in the second, and 458 colonies in 41 apiaries in the third. Samples for disease and parasite analysis were taken at 4 colonies per apiary. Ten colonies per apiary were inspected for Cape Problem Bees, and samples of workers were collected and dissected at each of these colonies. Even with the addition of apiaries to 'fill-up' lost colonies during the second survey, 63% of all colonies were lost by the third survey. There was only a small difference in colony loss between sedentary and migratory beekeepers of 22% compared to 27%. Nosema was more prevalent amongst commercial beekeepers and increased in migratory operations during the survey period. The percentage of colonies infected increased during the survey period from 23% to 32% to 34%. The placement of colonies in Eucalyptus plantations may boost infection. Trachea mites seem to have spread quite rapidly in South Africa since its discovery. This parasitic mite was present in all regions, although in low numbers in three most northern regions. Sedentary colonies had higher levels of infestation than migratory colonies. The number of colonies infested diminished over the survey period, which may be a result of general colony loss. The Cape Problem Bee was less of a problem than anticipated. Colonies succumbed to Cape Problem Bees in all regions. When beekeepers reported high levels of infestation in their bee stocks the colonies would be dead within six months. In apiaries with low infestation the die-out was slower.
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The perceptions that mentors and in-service teachers in the basic education teacher diploma have of the nature and role of the mentoring system
- Authors: Mostert, Johan André
- Date: 2004
- Subjects: Education -- Namibia Teaching -- Namibia Curriculum planning -- Namibia Educational change -- Namibia Teachers -- Training of -- Namibia Teachers -- In-service training -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1695 , http://hdl.handle.net/10962/d1003578
- Description: This contextual analysis is concerned with the study of the Basic Education Teacher's Diploma In-service Curriculum. It is based on the following assumptions: firstly, that the BETD (Inset and Preset) represents the Namibian Educational Reform in the realm of Teacher Education. Secondly, it is assumed that the BETD as a vehicle for reform in Teacher Education should yield teachers who are capable of change and development. Based on the above-mentioned assumptions, this analysis examines this Teacher Education course/programme against some criteria pertinent to its philosophy. A critical analysis of its curriculum in terms of some core subjects, as well as its practical implementation, will form the basis of this scrutiny. Secondary to the above, this analysis also intends to reflect this sociohistoric and economic context in which the BETD has been designed. An underlying motive in this analysis is to study the dynamics between the philosophy, which represents the heart and intention of the Namibian educational reform on the one hand and implementation which in turn delivers the end product or final outcome of the course on the other hand. This analysis should also fit into the current debate between conservatives who claim that the BETD lacks content and is therefore inferior, and those who claim that the course adequately prepares teachers for the needs of Basic Education.
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