Identifying the need for the development of an instrument to determine senior phase teachers' science-assessment competence
- Authors: Lombard, Elsa Helena
- Date: 2002
- Subjects: Science -- Ability testing -- South Africa , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Educational tests and measurements -- South Africa , Competency-based education -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10786 , http://hdl.handle.net/10948/100 , Science -- Ability testing -- South Africa , Science -- Study and teaching -- South Africa -- Port Elizabeth -- Evaluation , Educational tests and measurements -- South Africa , Competency-based education -- South Africa
- Description: The focus of this study is the competences expected of teachers in the senior phase to assess the Natural Sciences learning area. In order to be in line with the new developments, the South African science teacher will need relevant assessment training in order to utilise appropriate techniques that are in line with the new educational philosophy. The question arises: What competences do teachers need for assessing science in the senior phase? An ethnographic case study was implemented as research methodology in the descriptive research paradigm. The investigation comprised observing the classroom practices of a sample of three senior phase science teachers in two primary schools and in one secondary school in the Port Elizabeth region. The data obtained from the observations were triangulated with related artefacts produced by both the teachers and the learners in each case. In order to establish these expected competences a document analysis was done from a selection of South African documents. The descriptions of the real life assessment practices of the sample of science teachers were then compared with the competences expected by the South African education system. The comparison between the real-life assessment practices and the expected practices concurred with Shepard’s (2000, p.12) belief that the abilities needed to implement classroom assessment “are daunting”. The classroom-based assessment practices of the sample of teachers revealed a variety of assessment beliefs, practices and competence. The needs of these teachers are so diversified and intense that individualised professional development is needed if sustained implementation of the new curriculum and accompanying assessment competences is to be facilitated. The research established the need to develop an instrument that the science teachers can use to assess their own competence. There should be training modules drawn up in line with this instrument. Teachers should be able to choose the professional development modules that would address their own unique needs
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- Date Issued: 2002
The variation of conditions of employment
- Authors: Horo, Lindile
- Date: 2002
- Subjects: Labor laws and legislation -- South Africa , Labor disputes -- South Africa , Collective bargaining -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11043 , http://hdl.handle.net/10948/282 , Labor laws and legislation -- South Africa , Labor disputes -- South Africa , Collective bargaining -- South Africa
- Description: This paper seeks to bring clarity to a number of issues that arise from a process resulting from the unilateral variation of terms and conditions of employment and the conflict management and dispute resolution processes. The variation of employment terms particularly when it is driven by one party to the employment relationship can cause instability, insecurity, confusion and uncertainty to the parties involved. The nature of work is not constant and therefore changes are inevitable. This then has an effect of bringing disorder not only to the employer-employee relationship but also to the labour relations balance. In many instances and depending on whether it is the employer or employee who propagates the changes, the reasons to alter the conditions are different. Employers usually cite operational or economic reasons that are meant for the survival of the business as the need to make the changes. From the employees’ side the changes are necessitated by reasons aimed at a move from protecting the favourable employment conditions already acquired to improving them or attaining more. In the event that the parties to the employment relationship do not agree to the changes proposed and implemented, a dispute usually arises. This results from the failure of a consultation process, negotiations, persuasion or collective bargaining in general. In essence such a dispute arises from absence of consent to the changes. The failure of a bargaining system requires the process to assume a new nature. The dispute resolution systems and the conflict management systems follow as both the appropriate and necessary steps. The bargaining power together with the intervention of the third party is at the centre of this phase. The parties, depending on the nature of the dispute, the conditions that iv are changed and who are affected by the changes, have choices on what dispute resolution mechanisms to employ. The choice made has a huge impact on both the outcome required in the form of recourse, how the dispute will be resolved or how the conflict will be managed. There is legislative intervention with regards to the resolution of the conflictual scenarios that arise from disputes on unilateral variation of terms and conditions of employment. There are also non-statutory measures available to the parties. The choices are vast as to when can the variation take place, the reasons for the changes, the parties involved, the possible dispute resolution mechanisms, what can be varied and whether the unilateral implementation can be viewed as fair.
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- Date Issued: 2002
Barkly East bells and the British Empire
- Authors: Lewis, Colin A
- Date: 2002
- Language: English
- Type: Article
- Identifier: vital:6178 , http://hdl.handle.net/10962/d1012371 , http://www.ringingworld.co.uk
- Description: Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
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- Date Issued: 2002
Growth patterns of Pterocarpus angolensis in savannas of the South African lowveld
- Authors: Shackleton, Charlie M
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182373 , vital:43824 , xlink:href="https://doi.org/10.1016/S0378-1127(01)00676-4"
- Description: Pterocarpus angolensis D.C. is one of the most valuable indigenous timber species on the African continent south of the equator. Because of its high value, it is actively sought after in a number of countries, and wild populations are diminishing. However, attempts at artificial germination and growth trials have yielded poor results, thus, emphasis needs to be placed on sustainable management of existing populations. Success of in situ management will be enhanced if based on reliable data and knowledge regarding the growth patterns of this species within specific localities and countries. Such comprehensive data are lacking for several countries, including South Africa. This paper presents empirical data on a number of studies investigating the growth patterns of P. angolensis in the central lowveld savannas of South Africa, including phenology, annual diameter increment, size class structure, size of reproductive maturity, and morphometric relationships. The size class profile indicated that there was adequate recruitment of P. angolensis, but with constricted through growth from the suffrutex stage to the sapling stage. A small proportion of individuals attained reproductive maturity at 8 cm diameter, but most were bigger. All stems were reproductively mature by 26 cm diameter. This is below the minimum size for harvesting which is dictated by the need for a well developed heartwood. Annual growth was strongly related to stem size and rainfall during the growing season. Basal area increment of small stems was approximately four times greater than mature stems, and declined with increasing stem size. Over the 6-year-period and across all stem sizes, mean diameter increment was 4.5 mm per year. This rate is towards the lower end of the range of reported growth rates from other countries, and poses particular challenges for the sustainable management of this species in South African savannas.
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- Date Issued: 2002
A critical investigation into the managerial implications of inclusive education
- Authors: Cloete, Sanet
- Date: 2002
- Subjects: School management and organization -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1477 , http://hdl.handle.net/10962/d1003358
- Description: Special needs education has always provided special challenges to school administrators, policy makers and teachers. The world-wide move towards inclusive education as an alternative to exclusive education or casual mainstreaming has resulted in significant developments in Namibia in the past decade. Global educational reforms have focused on education for all as well as inclusive education and Namibia is signatory to several conventions and declarations in this regard. Research in this field has largely focused on the role of the inclusive teacher, and of course the special needs of the learners. Little or no attention has been paid to possible managerial and organisational challenges which accompany the move to inclusive education. This thesis seeks to critically investigate the managerial implications of inclusive education. The focal point of this research is to gain a clear understanding of the managerial implications in an inclusive school for learners with visual impairment, chiefly through an exploration of the experiences of management members of the inclusive process. The research is located within a qualitative research paradigm, which is subsumed by a phenomenological model. The data gathered through in-depth interviews include many anecdotal accounts that provide insight into the ways respondents reacted to experiences at the inclusive school. The main findings of the research are highlighted and discussed. Recommendations arising from a critical analysis of these main findings are presented.
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- Date Issued: 2002
Workshop theatre in post-apartheid South Africa : a case study
- Authors: Copteros, Athina
- Date: 2002
- Subjects: Theater -- South Africa , Theater -- Political aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2156 , http://hdl.handle.net/10962/d1007477
- Description: This is a qualitative study exploring the use of workshop theatre in post-apartheid South Africa, with the objective of making a contribution to the knowledge-base regarding its use in current times. Workshop theatre is changing in response to a new socio-political reality and emerging trends in theatre practice. The case study, of developing a play on Oystercatchers with a Grahamstown group of artists, revealed the difficulties and challenges of using workshop theatre in this dynamic context. Data collection included a focus group, observation, reflective discussion and in-depth interviews that were analysed in relation to available literature on workshop theatre in apartheid and post-apartheid South Africa. It is proposed that workshop theatre has continued relevance in post -apartheid South Africa. The process of creating workshop theatre with diverse artists has great potential to transform relationships, address issues of personal identity and to provide an underlying purpose to a workshop theatre -making context.
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- Date Issued: 2002
The registration of generic topical corticosteroid formulations in South Africa: a report
- Authors: Haigh, John M , Smith, Eric W
- Date: 2002
- Language: English
- Type: Article
- Identifier: vital:6368 , http://hdl.handle.net/10962/d1006068
- Description: [From the text]Topical corticosteroid formulations are used widely for a variety of skin conditions such as psoriasis and eczema. The most commonly used formulation types are cream, ointment, lotion and scalp application, with some mousse formulations being released recently onto the market for scalp application. The type of formulation used depends on the condition being treated. Dry lesions are normally treated with ointments and wet lesions with creams. Cosmetically, cream formulations are more acceptable as they can be rubbed in, thus leaving no residual oiliness. Scalp applications have to be less viscous to allow the formulation to pass through the hair and contact the scalp. Occlusion with plastic wrapping hydrates the stratum corneum and facilitates the passage of the corticosteroid through this barrier to the basal layer where the therapeutic effect is required.
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- Date Issued: 2002
Nutrient digestibility in South African abalone (Haliotis Midae L.)
- Authors: Sales, James
- Date: 2002
- Subjects: Abalones -- Digestion Abalones -- Nutrition
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5305 , http://hdl.handle.net/10962/d1005150
- Description: The evaluation of potential alternative protein sources for the formulation of least-cost optimal diets to satisfy the nutrient requirements of South African abalone (Haliotis midae) has been hampered by the absence of a suitable, practical, replicable and reliable digestibility technique. A suitable lowcost faeces collection technique was developed in this study to obtain suitable quantities of excreta for analysis from this species. Acid-insoluble ash was identified as a reliable, replicable and safe internal marker in comparison to chromic oxide and crude fibre for use in nutrient digestibility studies with H. midae. This was validated by the consistency and repeatability of the results and by comparison to total collection of faeces. The traditional substitution method used in digestibility studies with fish to evaluate protein digestibility of feed ingredients was found to be unsuitable for H. midae. Apparent protein digestibility values exceeding 100 % derived through this method could be attributed to associative effects between feed ingredients, differential diet and faecal nutrient leaching, and mathematical artifacts in calculations when using substitution versus single protein diets. An ingredient particle size of less than 450 μm in comparison to particle size classes of above 450 μm was shown to enhance nutrient (dry matter, organic matter, protein, fat) digestibility and minimise dry matter leaching from diets. The dietary inclusion level of both pre-gelatinised maize starch and a-cellulose did not influence (P > 0.05) apparent nutrient (protein, fat, fiber, starch) digestibility. Using the above digestibility protocol amino acid availability of all plants ingredients currently used in the South African animal industry was evaluated for H. midae. Soybean meal (96.86 %) and lupins (96.51 %) presented the highest apparent mean amino acid availability of all plant protein ingredients evaluated with H. midae. Canola meal (94.21 %), faba beans (92.87 %) sunflower meal (92.77 %), peanut meal (87.39 %) and cottonseed meal (85.15 %) presented higher apparent mean amino acid availability values than fish meal (82.75 %). Apparent protein digestibility was highly correlated (r = 0.99) with mean apparent amino acid availability, while true amino acid availability was 1.88 % units higher than apparent amino acid availability for all ingredients tested. Predicted apparent protein digestibility in compound diets was within 1.1-6.5 % of determined values. Calcium phosphate mono dibasic presented the lowest (P < 0.05) dietary phosphorus leaching (51.51 % maximum) and highest apparent phosphorus digestibility (66.27 %) in comparison to other inorganic phosphorus sources. Based on the method of direct experimentation to determine the optimal dietary protein level using graded levels of dietary protein 28.1-35.9 % dietary protein from good quality sources is recommended for maximum growth of juvenile H. midae. This study provides a scientifically sound research tool including a faecal collection technique, suitable marker and assay technique that could be use in further studies to improve least-cost diet formulation for H. midae. Future nutritional studies in H. midae should primarily concentrate on reducing dietary nutrient leaching and improving the intake of nutrients in order to properly evaluate responses of this species to different dietary regimes.
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- Date Issued: 2002
Valuation of intellectual capital in South African companies: a comparative study of three valuation methods
- Authors: Maree, Kevin W
- Date: 2002
- Subjects: Accounting
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:877 , http://hdl.handle.net/10962/d1001631
- Description: This study discusses three valuation methods for intellectual capital and considers two of these (Tobin’s “q” and CIV) as suitable valuation methods.
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- Date Issued: 2002
An investigation into the progress made towards achieving employment equity at Calsonic Kansei South Africa (PTY) Limited in terms of the Employment Equity Act no. 55 of 1998
- Authors: Ring, Grant
- Date: 2002
- Subjects: Affirmative action programs , Discrimination in employment -- South Africa , Affirmative action programs -- South Africa , Calsonic Kansei South Africa (Firm)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10895 , http://hdl.handle.net/10948/104 , Affirmative action programs , Discrimination in employment -- South Africa , Affirmative action programs -- South Africa , Calsonic Kansei South Africa (Firm)
- Description: The key aspect to stimulating economic and individual growth in the workplace has been shown in numerous case studies to be the removal of discrimination. Affirmative Action looks at dealing with, and making amends for past injustices, as well as moving towards equal employment opportunities in a constructive manner. It is about recognizing that people are inherently different whilst trying to achieve a “colour – blind” society. The Employment Equity Act No. 55 of 1998 was put in place by Government to facilitate the implementation of fair workplace practices, which will correct the imbalances of the past as well as creating a workforce, which reflects the demographics of South Africa. The inequalities in employment patterns and practices with respect to access to employment, training, promotion and equitable remuneration especially for black people, women and people with disabilities are addressed in the said Act. The Employment Equity Act is quite specific about the minimum requirements of an organisation’s Employment Equity Plan, which make it easy to identify what progress is being made towards ending discrimination in the workplace. The minimum penalty for contravening the Employment Equity Act is R500 000 and the maximum is R900 000. The question arises as to whether South African organisations are merely implementing Employment Equity policies to adhere to the basic requirements and deadlines of the Act. Or, are these policies genuinely based on commitment to the principles of equality and equal opportunity for all in the workplace. Calsonic Kansei South Africa has put into place various training and succession plans, which will help to achieve the organizational goal of being more equitable in terms of the Employment Equity Act. Employment agency databases have also been analysed to determine the availability of suitably qualified Affirmative Action employees. In this paper the writer will investigate the progress that Calsonic Kansei South Africa has made towards achieving Employment Equity in relation to other organisations within the same industry.
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- Date Issued: 2002
An investigation into the possible neuroprotective properties of phenytoin
- Authors: Naga, Nishal
- Date: 2002
- Subjects: Phenytoin -- Therapeutic use , Phenytoin -- Physiological effect , Nervous system -- Degeneration -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3780 , http://hdl.handle.net/10962/d1003258 , Phenytoin -- Therapeutic use , Phenytoin -- Physiological effect , Nervous system -- Degeneration -- Prevention
- Description: Cerebral ischaemia, traumatic injury to the brain, inflammatory neurological disorders and HIV infections are amongst the most prevalent causes of neurodegeneration. Neuroprotective strategies are usually to limit the progressive secondary injury that generally occurs, thus limiting overall tissue damage. Neuroprotective strategies are usually to limit the progressive secondary injury that generally occurs, thus limiting overall tissue damage. Sodium channel blockers have been often used for this matter as they prevent the cascade of events culminating in free radical generation and eventually neuronal apoptosis. Newer compounds, such as antiperoxidants and free radical scavengers, show encouraging experimental results, but their clinical use is still very limited. Phenytoin being a popular drug in the treatment of epilepsy has also been used as a neuroprotectant during certain neurological emergencies and in pharmacological prophylaxis of post-traumatic epilepsy. Furthermore this agent functions by prolonging inactivation of voltage gated sodium channels. In these sets of experiment the neuroprotective properties of phenytoin were examined. The histological study revealed that phenytoin confers protection to the CA1 and CA3 regions of the hippocampus under the insult of QUIN. Cells maintain their characteristic shape and minimal tissue necrosis occurs in the presence of this agent. The in vitro effect of this antiepileptic drug on free radicals generation shows that phenytoin does not reduce or prevent the formation of these reactive species. Lipid peroxidation was induced using QUIN and iron (II), two known neurotoxins. The study reveals that only lipid peroxidation induced using iron (II) is reduced by phenytoin. These experiments were carried out in whole rat brain homogenate. These studies show that phenytoin possesses poor free radical scavenging properties. However, the dose-related reduction of iron-induced lipid peroxidation allows for speculation that phenytoin interacts with iron in order to reduce neuronal damage. Metal binding studies were performed using UV, IR and electrochemical analysis to examine the interaction of phenytoin with iron (II) and iron (III). Phenytoin, when added to iron (II) in solution, first oxidises the latter to iron (III) and maintains it in that form. A shift in the peak was observed in the UV spectrum when iron was added to phenytoin. Moreover, electrochemical studies indicate that the interaction between the metal and the ligand is very weak. The IR analysis it shows that phenytoin may be coordinating with iron through the Nitrogen atom on the phenytoin molecule. These studies show that phenytoin maintains iron in its oxidised form, which is a good property to possess as a neuroprotectants. Pineal organ culture showed that phenytoin does not increase melatonin production but slightly and non-significantly reduces the levels of this pineal hormone. However there is a significant rise in precursor NAS levels. As melatonin is known to possess antioxidant and free radical scavenging properties, this could mean that this drug can cause the CNS to become more susceptible to attacks by reactive oxygen species.
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- Date Issued: 2002
An exploration of functional and numerical flexibility in South African organisations: a qualitative study in two textile factories in Cape Town
- 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
Accelerated carbon dioxide deliming of cattle hides and sheepskins
- Authors: Flowers, Karl Bernard
- Date: 2002
- Subjects: Tanning , Hides and skins , Carbon dioxide
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3918 , http://hdl.handle.net/10962/d1003977 , Tanning , Hides and skins , Carbon dioxide
- Description: To avoid environmental pressure from water authorities, specifically regarding nitrogen and sulfate limits in tannery wastewater, modifications to existing deliming processes have been made. Conventional ammonium salt deliming methods contribute to Total Kjeldahl Nitrogen values in the region of 0.5 – 1.0g/L (33-67% of total TKN). Sulfate levels are increased with the use of organic deliming and ammonium sulfate deliming to the extent of 0.9g/L (27% of total sulfate). To understand the dynamics and kinetics of carbon dioxide equilibrium, the movement of carbon dioxide into deliming water, through carbonic acid, bicarbonate and ultimately into carbonates at liming or early deliming pH was studied. It was shown in this study that effective lime removal, at optimum conditions, resulted in fully delimed pelts at highly comparable quality and times compared to conventional ammonium salt deliming
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- Date Issued: 2002
The biotransformation of phenolic pollutants using polyphenol oxidase
- Authors: Boshoff, Aileen
- Date: 2002
- Subjects: Polyphenol oxidase Sewage -- Purification
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3976 , http://hdl.handle.net/10962/d1004035
- Description: The potential of using mushroom polyphenol oxidase (EC 1.14.18.1) as a biocatalyst for the biotransformation of phenols to produce catechols in an aqueous medium was investigated. Polyphenol oxidase is characterised by two distinct reactions i.e., the ortho-hydroxylation of phenols to catechols (cresolase activity) and the subsequent oxidation of catechols to orthoquinones (catecholase activity). In order to facilitate the development of a process to produce catechols, the accumulation of catechol as a true intermediate product released in the reaction system needed to be investigated, as its release had been disputed due to the oxidation of catechols to o-quinones. Using LC-MS, catechol products were successfully identified as true intermediate products formed during biocatalytic reactions in water.
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- Date Issued: 2002
Building brand loyalty within selected segments of the South African fast moving consumer goods market
- Authors: Terblanche, Etienne
- Date: 2002
- Language: English
- Type: Thesis , Masters , MTech (Marketing)
- Identifier: vital:10774 , http://hdl.handle.net/10948/d1002108
- Description: The rapidly increasing competitiveness within the fast-moving consumer goods (FMCG) market compels an organisation within this market to not only entice consumers to purchase the organisation’s brand, but also to keep these consumers purchasing the brand. It is therefore essential that an organisation creates and maintains loyalty among consumers towards its brand. The objective of the research was to find out what strategies an organisation could implement to achieve and sustain loyalty from current and prospective consumers towards its brand in a highly competitive, FMCG market. The main areas of focus were as follows: Establishing the basis on which consumers differentiate between homogenous products. Determining what strategies an organisation could utilise to ensure that consumers will differentiate its brand from those of competitors. Obtaining relevant information to find out what variables motivate consumers to be brand loyal within the FMCG market. Ascertaining how an organisation could build a brand. Determining how an organisation could maintain brand loyalty from its existing consumers. The research included a study of relevant literature and an empirical study. The aim of the literature study was to obtain a solid base of information and opinions regarding the concepts of brands and building brand loyalty. Making use of structured questionnaires and through performing personal interviews, the empirical study consisted of two aspects. The one aspect was a brand loyalty survey conducted among 303 respondents, and the second aspect was a brand loyalty survey conducted with nine owners or marketers of leading brands. The following were the major findings of the research: Relying on being a leader in price and quality is not enough to ensure that a consumer would continue purchasing an organisation’s brand. A brand is an experience and in order for a consumer to become loyal towards a brand, the consumer should have a host of positive thoughts regarding past experience with the brand. It is essential that organisations within the FMCG market proactively develop and implement strategies aimed at creating and maintaining loyalty towards their brands.
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- Date Issued: 2002
A description of spatial and temporal aspects of the lifecycle of chokka squid Loligo vulgaris reynaudii on the inshore spawning grounds and Agulhas bank off the South Coast of South Africa
- Authors: Olyott, Leonard James Henry
- Date: 2002
- Subjects: Squids -- South Africa , Loliginidae -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5253 , http://hdl.handle.net/10962/d1005096 , Squids -- South Africa , Loliginidae -- South Africa
- Description: The chokka squid, Loligo vulgaris reynaudii, is a commercially important species supporting a large, high-value export fishery for South Africa. This study reviewed its population dynamics and reproductive biology. Biological information collected on biannual research cruises from September 1986 to April 1999 on the Agulhas Bank as well as information from commercial vessels operating in the inshore environment collected between April 1988 and July 1989 and again between June 1999 and May 2000 were analysed. Size ranges of juveniles, subadults and adults were calculated and used to determine seasonal distribution and abundance patterns. Based on Gonadosomatic Indices (GSI) and percentages of mature squid in each month, two peak reproductive seasons in summer and winter were identified although mature squid were present all year round. Seasonal peaks in sex ratio were also apparent with males outnumbering females by up to 4:1 in the peak-breeding season. The size at which squid matured, demonstrated both spatial and temporal patterns. Squid caught in spring matured at a smaller size than squid caught in autumn and at successively smaller sizes from west to east across the Agulhas Bank. Size at maturity was highly variable especially in males where “sneaker males” were evident in both seasons. Length-to-weight linear regression revealed significant differences between maturity stages and between sexes. Females demonstrated steeper length-to-weight regression slopes than males in the peak-breeding seasons. Aspects of squid biology pertinent to fishery management were highlighted as well as potential areas where research should be directed in order to develop future stock assessment models.
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- Date Issued: 2002
Open source in South African schools : two case studies
- Authors: Halse, G A , Terzoli, Alfredo
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6089 , http://hdl.handle.net/10962/d1009742
- Description: One of the major problems facing schools in South Africa is the difficulty in obtaining modern, up-to-date computer facilities. This paper looks at the use of open source solutions in two government schools in South Africa to demonstrate that it is possible for schools to utilise almost any existing computer to provide effective network solutions.
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- Date Issued: 2002
A comparison of anthropogenic and elephant disturbance on Acacia xanthophloea (fever tree) populations in the Lowveld, South Africa
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181629 , vital:43753 , xlink:href="https://doi.org/10.4102/koedoe.v45i1.10"
- Description: Acacia xanthophloea (the ‘fever tree’) is a popular medicinal species that is traded widely in South Africa. Although it occurs throughout southern Africa, there is increasing pressure on its riverine and marshy habitats. This study compares the impact of harvesting on an A. xanthophloea population located on private land near Komatipoort, Mpumalanga, with two protected populations situated within the Kruger National Park. The densities of the harvested and protected populations were similar (84±8 trees/ha and 85±20 trees/ha, respectively). There were fluctuations in the quotients between frequencies of trees in successive diameter classes, which is common in savanna where high levels of fire, mega-herbivore and anthropogenic disturbance are experienced. The extent of stem damage (stripping of bark and breakage) by elephants in the protected area was significantly higher than the extent of harvesting on private land, although the degree of damage was relatively low, with only 7 % of the populations having been damaged at rates >26 %. The degree of harvesting on private land was relatively low, with the majority of trees having been harvested at rates of less than 10 % of the stem below 2 m. Despite this, ringbarking had occurred (4 %). The basal diameters and heights were significantly lower in the protected population than in the harvested one, suggesting that over time elephant impact was the more severe disturbance. Acacia xanthophloea exhibited high resilience to disturbance, with all the elephant damaged trees and harvested individuals surviving. However, the mean bark thickness measured in local markets (6.3±1.4 mm) was significantly lower than that measured in either the harvested (12.4±1.0 mm) or the KNP (10.3±0.8 mm) populations. As harvesters tend to select the largest individuals in a population to maximise their financial returns, this could mean that smaller individuals are being harvested, and/or bark is not being given sufficient time to grow back after harvesting. Acacia xanthophloea outside protected areas thus need to be monitored and the management improved, preferably in conjunction with the resource users. In addition, traditional healers, those selling medicinal plants and other members of the community need to continue to be encouraged to cultivate this fast growing species.
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- Date Issued: 2002
Continuity and generalized continuity in dynamics and other applications
- Authors: Mimna, Roy Allan
- Date: 2002
- Subjects: Topological dynamics -- Research Dynamics -- Mathematical models -- Research Perturbation (Mathematics) Attractors (Mathematics) Baire classes Mathematics -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5404 , http://hdl.handle.net/10962/d1005218
- Description: The topological dynamics of continuous and noncontinuous dynamical systems are investigated. Various definitions of chaos are studied, as well as notions of stability. Results are obtained on asymptotically stable sets and the perturbation stability of such sets. The primary focus is on the traditional point sets of topological dynamics, including the chain recurrent set, omega-limit sets and attractors. The basic setting is that of a continuous function on a compact metric space, sometimes with additional properties on the space. The investigation includes results on the dynamical properties of typical continuous functions in the sense of Baire category. Results are also developed concerning dynamical systems involving quasi-continuous functions. An invariance property for the omega-limit sets of such functions is given. Omega-limit sets are characterized for Riemann integrable derivatives and derivatiyes which are continuous almost everywhere. Techniques used in the investigation and formulation of results include finding theorems which relate the rather disparate notions of dynamical properties and generalized continuity. In addition to dynamical systems, numerous other applications of generalized continuity are imoestigated. Techniques used include application of the Baire Category Theorem and the notion of semi-closure. For example, results are formulated concerning functions determined by dense sets, including separately continuous functions, thus generalizing the classical result for continuous functions on dense subsets of the domain. The uniform boundedness theorem is extended to functions which are not necessarily continuous, including various derivatives. The closed graph theorem is strictly generalized in two separate ways, and applications are presented using these generalizations. An invariance property of separately continuous functions is given. Cluster sets are studied in connection with separate continuity, and various results are presented concerning locally bounded functions.
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- Date Issued: 2002
A history of confession: the dialogue between cynicism and grace in selected novels of J.M. Coetzee
- Authors: Hornby, Catherine Muriel
- Date: 2002
- Subjects: Coetzee, J. M., 1940- -- Criticism and interpretation , Cynicism in literature , Grace (Theology) in literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2190 , http://hdl.handle.net/10962/d1002232 , Coetzee, J. M., 1940- -- Criticism and interpretation , Cynicism in literature , Grace (Theology) in literature
- Description: In introducing the four novels under discussion as a “History of Confession”, this study explores the resistance to the dominant discourse of ‘history’ offered by the sustained confessions of individuals. In examining Coetzee’s oeuvre it is possible to delineate the outline of a dialogue between cynicism and grace, and the effects of these on the process of confession in each of the works Chapter One, dealing with Age of Iron, draws on Levinas’ theory of ‘the Other’ in order to elucidate the role played by the interlocutor or confessor in the process of confession.The recognition of the passage of the self through the Other is integral to the attainment of a state of grace, without which confession cannot be brought to an end The countermanding claims of the writer's will-to-write and duty to society are illuminated as a source of cynicism which overwhelms the intervention of grace. The Master of Petersburg, discussed in Chapter Two, is a confession of the guilt and despair faced by the writer who sacrifices his soul to answer the urge to write. Chapter Three, which examines Coetzee’s excursion into autobiography, represents a continuation of the confessional trend. The distance between the narrator and protagonist of Boyhood illustrates the convolutions of self-deception in the process of confession. The chapter which deals with Disgrace identifies a new trend in Coetzee’s writing:the concern with animals. Levinas’ theory, which identifies the encounter with the Other as necessary to precipitate an intervention of grace, is again useful in explaining how Coetzee has postulated the unassimilable otherness of animals as primary to human ethical development. This chapter also concludes that Disgrace represents a high point in the recovery of both grace and agency in Coetzee’s oeuvre.The concluding chapter suggests that the accumulation of meanings to the term ‘grace’enables its definition as a semi-religious abstraction. Coetzee suggests that belief in its existence has the power to affect interactions on the physical plane, especially those between the self and the Other.
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- Date Issued: 2002