The purpose of this abstract is to report on the results of the study conducted to identify misconceptions concerning chemical equilibrium concepts, and to investigate the effectiveness of Laboratory Based Teaching (LBT) compared to Traditional Based Teaching (TBT) on University of Limpopo Foundation Year (UNIFY) students' understanding of chemical equilibrium concepts. The subjects of this study consisted of 53 UNIFY students from two chemistry classes. The data were obtained from 27 students receiving LBT and 26 students in the TBT. The validated Misconception Identification Test (MIT) was administered to diagnose students’ misconceptions in different areas of chemical equilibrium. Analysis of the Pre-MIT and open-ended responses revealed widespread misconceptions such as: • Left – and right – sidedness: Students perceive each side of a chemical equation as a separate physical quantity. • The constancy of the equilibrium constant: This includes the ability to judge when and how the chemical equilibrium constant changes. This possible misconception refers to the changes in concentration, pressure and temperature as well as the addition of a catalyst. For example, students fail to grasp the influence of the catalyst on a chemical system, viz., that it has an effect on the reaction rates but not on the equilibrium as such. They perceive the catalysts as leading to a higher yield of the product. • Rate versus extent: Inability to distinguish how fast the reaction proceed (rate) and how far (extent) the reaction goes. • Definition of equilibrium constant expression: Inability to relate the equilibrium concentrations of reactants and products using the equilibrium law. • Misuse of Le Chaterlier’s principle: The application of Le Chaterlier’s type reasoning in inappropriate situations. To address the identified misconceptions, practical based activities on certain aspects of chemical equilibrium were developed as resource material for one group of students (Laboratory Based Teaching - LBT) and similar activities having the same chemistry content consisting of tutorial questions, theoretical background of some aspects and some experiments were used as resource material for the other group (Traditional Based Teaching - TBT). After both instructions, analysis of the Pre MIT and Post MIT results using t – test statistic for each group revealed significant difference between the means of the sample. This implied that both instructions have contributed significantly to the students’ improvement in their misconceptions. Again after both instructions, analysis of the Post MIT results for the two groups using the t-test revealed a significant difference between the two group’s sample means. This implied that the misconceptions in the LBT group were reduced significantly as compared to misconceptions held by students in the TBT group. After both instructions, more students in the LBT group had correct representation of mental models of reactions in equilibrium than the students in the TBT group. Implications for science education classroom practice are also discussed. / Dissertation (MSc (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted

The objectives of this study were to evaluate the quantity and quality of cashmere produced by South African indigenous goats under different environmental conditions and to compare two techniques (Video Image Analyser-VIA and Optical Fibre Diameter Analysis-OFDA) which were used for fibre diameter analysis. The study was conducted in Irene, University of Pretoria, Mara, Delftzyl, Roodeplaat and Centurion. In this study three breeds namely Indigenous, Boer and Savanna goats were used and a total of 217 animals were combed during the moulting season (July to September) in 1997. Location and colour of the animals had significant effects on fibre yield and diameter (P<0.05). The Boer goats produced significantly (P<0.05) more fibre, which was coarser, compared to the indigenous goats, irrespective of age of the animal. The savanna goats produced good quality cashmere which was comparable to that produced by Boer goats and indigenous goats. Males produced significantly more and coarser fibre than females (P< 0.05). Reproductive status did not show any significant effects (P>0.05) on yield but the lactating animals produced very little cashmere per annum. Age had no significant effects (P>0.05) on total yield and diameter although both yield and diameter increased with age. According to the results of this experiment, the VIA technique resulted in more accurate fibre diameter values compared to the OFDA technique. The cashmere fibre diameters measured by the VIA were 5 <font face="symbol">m</font>m finer than with the OFDA, while guard hair diameters by the OFDA were 27 <font face="symbol">m</font>m thicker than diameters by the VIA. The correlation between these two techniques was very low, with r2 of 27.1 for cashmere and 16.0 for guard hair respectively. The South African indigenous goats produced good quality (fine) fibre, with fibre diameter ranging between 9 and 14 <font face="symbol">m</font>m, although the quantity was very small. This fibre diameter range meets the requirements for cashmere diameter as recommended by the cashmere industry. / Dissertation (MSc (Animal Production))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted

Field data were collected and analysed on the feeding and spatial ecology of brown hyaenas living in the Makgadikgadi National Park and in an adjacent Wildlife Management Area where local subsistence pastoralists live. The responses of the pastoralists to a questionnaire designed to document their perceptions of and attitudes towards brown hyaenas and other carnivores that live in the vicinity of their residences, were also analysed. Brown hyaenas living in the Makgadikgadi National Park have different diets from hyaenas living in the vicinity of pastoralists. In pastoralist areas livestock carcasses were the most important food source and other less important food types were fed on as they became seasonally available. In the Makgadikgadi National Park zebra was the most important food source although several other food types were seasonally important. In the pastoralist areas dietary breadth was similar over the lean and the peak seasons, while in the Makgadikgadi National Park, when food availability was low in the lean season, the brown hyaenas increased their dietary breadth and fed off a greater number of species of food. In the lean season they also changed their foraging behaviour. There was no evidence to suggest that any livestock species were hunted by the brown hyaenas as springhares and Cape hares were the only mammals observed to be hunted, and only occasionally. Home range sizes were smaller for brown hyaenas living in the vicinity of pastoralists than for hyaenas living in the Makgadikgadi National Park. The size of the home range was found to be dependent on the average distance between the significant food sources. In the Makgadikgadi National Park the seasonal home range size fluctuated greatly due to the variability of seasonal food available, while in the pastoralist areas food availability was less varied and as a consequence seasonal home range size varied less than in the national park. Although pastoralists believed that black-backed jackals killed the most number of individual livestock animals, lions had the greatest perceived negative economic impact, followed by black-backed jackals, spotted hyaena and then brown hyaena. Wild dog, caracal, cheetah and leopard were also believed to have killed a small number of livestock animals. The general understanding of the brown hyaena is that it is a predator that survived by feeding on hunted livestock. As a consequence of this they were hated and frequently killed by the farmers. In spite of their persecution the brown hyaena populations are viable in the cattle areas and appear not to be under any immediate threat. However, efforts to reduce the number of brown hyaenas killed in the long-term would be beneficial in ensuring that brown hyaena populations in cattle areas remain viable. / Dissertation (MSc (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

This study attempted to correlate the chemical and physical properties of the para disubstituted and para monosubstituted biphenyl complexes of 4,4'-DNBP with their structural and electronic properties, using a variety of physical and spectroscopic techniques, and X-ray diffraction methods. These complexes drew considerable attention in the past due to their capacity to demonstrate intense colours from yellow to dark red, which are dissimilar to the colour combination of their parent compounds. This prompted a series of investigations in the past through which the full structure of only Complex of 4,4'-Dinitrobiphenyl with 4- Hydroxybiphenyl (C-4OHBP) by single crystal diffraction was determined and the infrared and Raman spectra of C-4OHBP, Complex of 4,4'-Dinitrobiphenyl with Biphenyl (C-BP) and Complex of 4,4'-Dinitrobiphenyl with 4-Bromobiphenyl (C-BrBP) were obtained. In this study, other para-disubstituted biphenyl complexes with 4,4'-DNBP were investigated to add to the existing knowledge base and to study the effects of varying the substitution on the aromatic rings of the donor. Because the complete solid state structures of the complexes in this study (except C-4OHBP) and the donor compound BZ are not known, their single crystal determination was attempted. Unfortunately, no suitable diffraction quality crystals could be crystallised. Although the X-ray crystal structure of 4,4'-DNBP was determined by photographic methods by Van Niekerk and Boonstra, the R-factor of this solution was relatively high at 15%, which is outside the current internationally accepted standard. Because the current technology using automated diffractometers is superior to photographic techniques used by Van Niekerk and Boonstra, it was decided to repeat the crystallographic analysis for 4,4’-DNBP. However, despite repeated efforts with a large variety of solvents used during the crystallisation process in this study, the crystals formed were of a relatively poor quality, resulting in a solution with a final R-factor of also only 15%. Therefore, the only crystallographic data available for correlation with the physical properties of the complexes have been that of the uncomplexed compounds (except BZ) and C-4OHBP from the previous studies. Based on these results, the comparison of the dihedral angles between the two aromatic rings of the parent compounds with their infrared and Raman spectra yielded that, unlike the conventional compounds the centrosymmetricity of the biphenyl derivatives cannot be uniquely determined by their infrared and Raman spectra. Using thermogravimetric measurements, melting points and phase transitions of each pure component and as well as the complexes were obtained. Packing energy in the complex seems to be relatively more favourable than in the parent components alone. Otherwise, two phase transitions could be expected, one resulting from 4,4'-DNBP and one resulting from the other component in the complex. Complex of 4,4'-Dinitrobiphenyl with 4,4'-Dihydroxybiphenyl (C-44DiOHBP) and Complex of 4,4'-Dinitrobiphenyl with Benzidine (C-BZ) showed some unexpected high melting points in their thermogravimetric studies. These elevated melting points are interpreted as resulting from hydrogen bonding, and infrared studies of these complexes confirmed this interpretation. Conductivity measurements in the solid state revealed that only tmethylbz exhibits a measure of charge transfer. The absence of current in both its complexes (1:1 and 1:4 ratio) with 4,4'-DNBP was attributed to the close-packing and twisting of the components in the complex which prevented the electron flow through the complexes. Because ultraviolet-visible, infrared and Raman spectra showed only small shifts in the pure compounds after complexation in solution, and their conductivity measurements revealed no current flow, the interactions in those complexes are ascribed mainly to Van der Waals forces. The previously assigned molecular ratios are incorrect. This study has reassigned these molecular ratios using nuclear magnetic resonance techniques. Nuclear magnetic resonance spectroscopy detected only very small chemical shifts in the pure compounds after they formed complexes in solution. As these solutions did not maintain the colour of complexation, this could be seen as supportive proof that all the interactions involved in the formation of these complexes are very weak. The same conclusion as the previous studies has been reached, notably that the molecular ratios, in which the components of these complexes unite, are caused almost exclusively by packing factors and are stabilised by weak interactions. / Dissertation (MSc (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted

The purpose of this research study was to investigate how the quality of formative assessment in the Department of Defence Supply Support environment can be improved. Although formative assessment is applied in the Department of Defence, several limitations in the application thereof were found. The investigation was done on the Initial Supply Support learning programme at the Department of Defence School of Logistical Training Satellite in Pretoria. A small group of 19 learners (N=19) who attended the mentioned learning programme together with the assessor, who presented it, were selected as the target group. Action research with the stages as proposed by Hodgkinson and Maree (1998) was used in this study. Using action research in this study could be characterised by a cyclical nature of planning, implementing, observing and evaluating. This cyclical nature lends it to provide information during the evaluation stage, which can be used in the planning stage of a new cycle of action research. The five phases from Lategan and Van Rooyen (1998) as amended by the researcher, were used as a formative assessment process together with action research in order to investigate how the quality of formative assessment can be improved. Aligning the amended five phases of formative assessment with the four stages of action research resulted in; planning and designing with the planning stage of action research, collecting evidence with implementation, judging evidence and making recommendations were aligned with observation and providing feedback and further development with the evaluation stage of action research. The concepts and principles as identified from the literature and analysed by the researcher were applied to each of the amended five formative assessment phases. The principles can by used as a set of standards, which an assessor should adhere to in order to improve formative assessment by using it as a process together with action research. Applying formative assessment as a process, together with using action research in this study, indicated that the quality of formative assessment could be improved. / Dissertation (MEd (Assessment and Quality Assurance))--University of Pretoria, 2006. / Curriculum Studies / unrestricted

The research was aimed at determining whether Grade Nine teachers benefited from the training in Curriculum 2005 assessment techniques that was organised by the Department of Education and whether the training contributed to meeting the intellectual and professional challenges facing South Africans in the 21st century. For this purpose a predominantly rural midlands district of the Pietermaritzburg region of the KwaZulu-Natal Department of Education was selected. The study followed a qualitative approach. Data was collected from three Grade Nine teachers from three rural schools who were responsible for teaching the following: languages, social sciences and mathematics. The study found that the teachers felt that they had not been trained adequately in the above learning areas, and therefore did not understand the new procedures. The procedures could also not be implemented within the teaching time allocated to the respective learning areas. In addition, the teachers felt that the paper work involved in the implementation of the new procedures had increased their workload unnecessarily. The training failed to prepare them for Curriculum 2005 and the assessment guidelines provided by the Department. The cascading of information resulted in the misinterpretation of important information. Furthermore, trainers lacked confidence, knowledge and understanding of the management of the training process. District officials who conducted training did not understand the terminology and used teaching methods that were non-consistent with outcomes-based education (OBE) and Curriculum 2005. At the school level, there was considerable overlap in planning and no clear solutions to this problem. Finally, the teachers regarded one week as inadequate for training and the training materials as insufficient for the teacher learning. The study concludes with recommendations for the successful implementation of Curriculum 2005 and for further research. / Dissertation (MPhil (Community Development))--University of Pretoria, 2006. / Education Management and Policy Studies / unrestricted

Human resource development needs to take cognisance of the unique challenges the workplace of the future will pose for individuals in order to be able to effectively prepare individuals for the future. The objective of this study was to evaluate a training programme that was based on the principles of social constructivism and focused on developing people for the workplace of the future. A non-equivalent groups design with a pre-and post-measurement was used to evaluate the programme. The experimental group consisted of thirty-six individuals and the control group consisted of twenty individuals. The training programme contributed to a significant increase in the creativity, adaptability and self-acceptance of the experimental group (compared with the control group). These characteristics are necessary to succeed in the future workplace. The training programme thus made a valuable contribution to the development of the experimental group for the workplace of the future. / Dissertation (MCom (Human Resources Management))--University of Pretoria, 2006. / Human Resource Management / unrestricted

Pig production is a techno-scientific internationalized business that is continuously exposed to change and risk. Changes in the Agri-Business are inter alia caused by changes in globalization, information technology, biotechnology and changes in consumer trends. The consumer, within the framework of the pig supply chain, is fundamental to this study. Hence an in depth review of meat market surveys for the period 1970 – 2000 was undertaken. The central theme of the study is: "How to reconcile meat quality, genetics and the consumer with bio-economic pig production in the South African pig supply chain?" A detailed analysis of the South African pig supply chain was subsequently conducted in order to add value further down the supply chain. The inherent structure of the South African pig industry was researched with the emphasis on production statistics, the pig feed industry, genetic improvement and pig information systems, slaughter houses and also slaughtering statistics. The different industry institutions, industry organisations and computer programmes in support of the South African pork supply chain were also investigated. Genetics is the hidden golden thread running through any livestock supply chain. If a substantial portion of consumer satisfaction and quality assurance can be resolved (guaranteed) at the genetic level (thus conception), these guarantees will be conducive to quality assurance further down the supply chain. Carcass and meat quality have become increasingly important in modern day pig production, despite the fact that the emphasis has been too long on input efficiency and too short on output efficiency in South Africa. This called unambiguously for the accurate estimation of genetic parameters of production and carcass traits through appropriate methodology and the right genetic technology. A high degree of accuracy will further optimize the estimation of breeding values, that of breeding objectives and also enhance the credibility of a national breeding scheme. Genetic parameters for five carcass traits were successfully estimated for the first time in the history of South African pig breeding. In future, breeding values for carcass traits, can now be determined more accurately for the Large White, Landrace and Duroc pig breeds. Extension of the present carcass evaluation analysis (Phase E of the National Pig Performance Testing Scheme) to incorporate the essential meat quality traits such as pHu, marbling, tenderness and colour into future breeding goals should eventually satisfy the consumer. In order to finally progress from an immature to a mature pig supply chain, pig producers must align themselves with value partners on both the input (raw materials) and output (end product and value added products) end of the supply chain. To embrace the concept of quality (a consumer demand principle) all levels in the production chain (at the genetic level through the breeding objectives, at the farm level through the entire production system, in transit and at the slaughterhouse and processing levels) should be integrated. / Thesis (DPhil (Agricultural Economics))--University of Pretoria, 2006. / Agricultural Economics, Extension and Rural Development / unrestricted

The aim of this study is to determine whether or not the Career Path Appreciation (CPA) is cultural unbiased. The use of assessment instruments in South Africa has been criticised, because it is said that they are largely based on the values and knowledge of overseas instruments, which are considered to be less valid for South Africa’s various cultural groups. In this study, an Asian, black, coloured and white group were included to determine the cultural equivalence of the CPAs measurement outcomes. The results indicate that the CPA measurement outcomes are not biased and are, therefore, equivalent for groups of diverse cultural backgrounds. / Dissertation (MCom (Human Resources Management))--University of Pretoria, 2006. / Human Resource Management / unrestricted

The purpose of this study is to determine if there is a relationship between personality traits and vocational interests in the South African context. A sample of 770 subjects completed the Sixteen Personality Factor Questionnaire (16PF) and the Interest Questionnaire (INQ). The Pearson’s r indicates a number of low and moderate correlations between the factors on the 16PF and interest fields of the INQ. Partial correlations conducted shows that gender and race may influence these relationships, however these were slight changes. It is evident that a relationship exists between personality and vocational interest but seems to be weaker in the South African context than those found in studies conducted in Europe and the United States of America. / Dissertation (MCom (Human Resources Management))--University of Pretoria, 2006. / Human Resource Management / unrestricted