The effects of booster breaks during a sedentary night shift on physiological, psychomotor, psycho-physiological, and cognitive performance over a 3 night shift habituation phase
- Authors: Lombard, Wesley Ross
- Date: 2010
- Subjects: Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5116 , http://hdl.handle.net/10962/d1005194 , Night work , Shift systems , Performance , Exercise , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Cognition -- Effect of exercise on , Motor ability
- Description: Despite extensive research into shift work, workers working under rotating shift conditions are still plagued by the effects of the desynchronisation resulting from working against their natural circadian rhythms. Additionally, modern industries are shifting towards tasks requiring greater cognitive demand with less manual labour incorporated into the tasks. Research into operator based tasks, and hence those of a sedentary cognitive base both during day and night shifts, has been focusing on the effectiveness of the standard rest/break schedule. Research indicating that the standard rest break schedule is often ineffective in eliminating operator discomfort and performance deterioration, with these affects argued to be more pronounced during a night shift schedule. Therefore current research set out to investigate alternative rest break schedules, incorporating a short bout of physical activity and stretching exercises which are proposed to enhance performance and subjective mood, while eliminating operator discomfort for sedentary based cognitive tasks. Three conditions were tested during a three day habituation shift cycle within a laboratory, incorporating two night shift groups (control and experimental) and a control day shift group. Twelve subjects made up each group, with the two night shift groups completing the shift schedule together. The control groups followed a typical 8 hour shift schedule while the experimental group performed a booster break (exercise and stretches) activity for 7.5 minutes every hour during the night shift schedule. Over the course of the shift, subjects completed a battery of six tests providing data on physiological measurements (heart rate and temperature), performance criteria (reaction time responses, memory and neurobiological) and subjective measures. Responses obtained for all the different parameters measured indicated a strong circadian influence for the majority of the variables, indicating the course of natural down regulation within physiological and performance criteria over the night shift. The booster break significantly improved reaction time performance, subjective ratings and resulted in a high sustainable activity level. Day shift comparisons indicating that within subjective measures and reaction time performance, the booster break resulted in similar responses to those of the day shift workers, while the control night shift groups reported significantly lowers results. Additionally, the booster break had positive influences during the circadian nadir, significantly improving parameters of performance and subjective ratings of sleepiness. The results of this study indicating which variables are strong predictors and indicators of the oscillations in performance and subjective ratings due to the circadian changes. The booster break interventions had positive effects on subjective ratings and reaction time performance, while also being argued to decrease the burden placed on the cardiac system as a result of increased sympathetic tone during the night shift, while additionally resulting in similar responses to those of day shift workers. Further studies are required, however, to provide conclusive evidence particularly within a working situation over a longer shift schedule.
- Full Text:
- Date Issued: 2010
The effects of economic incentives in controlling pollution in the South African leather industry: die uitwerking van ekonomiese insentiewe op die beheer van besoedeling in die Suid-Afrikaanse leerbedryf
- Authors: Mowat, Shaun P , Antrobus, Geoffrey G , Fraser, Gavin C G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143057 , vital:38197 , DOI: 10.1080/03031853.1997.9523487
- Description: Pollution of the environment is becoming an increasingly serious problem. A large contributor to this is industry which generates effluent as a by-product of its production process. Two methods of controlling the pollution generated by industry are the so-called “command and control” techniques and economic incentives. In theory, economic incentives promise a more economically efficient and equitable means of pollution control. This paper sets out to ascertain whether this would hold in practice by applying environmental economic theory to the practical problem of controlling the effluent generated by one particular industry, viz the South African leather industry.
- Full Text:
- Date Issued: 2010
The effects of glove fit on task performance and on the human operator
- Authors: Stack, Jessica Danielle
- Date: 2010
- Subjects: Hand -- Anatomy , Hand -- Wounds and injuries , Hand -- Care and hygiene , Gloves , Safety education, Industrial , Human-machine systems , Industrial safety , Industrial accidents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5119 , http://hdl.handle.net/10962/d1005197 , Hand -- Anatomy , Hand -- Wounds and injuries , Hand -- Care and hygiene , Gloves , Safety education, Industrial , Human-machine systems , Industrial safety , Industrial accidents
- Description: The hand is one of the most complex of all of the anatomical structures in the human body. It has been found that hand injuries are among the most frequent injuries that occur to the body, predominantly during industrial activities. It has therefore been concluded that more research is needed into protective factors, such as glove use. The design features of a glove emphasise either protection or performance. There is often a trade-off between increased safety and performance capability when donning gloves. It has been determined that gloves which are fitted and comfortable for the worker may provide the best compromise between protective functions and decreased performance. This investigation aimed to assess the influence of glove fit on the performance attributes of industrial tasks, as well as on the responses of the human operator. Glove fit was analysed as 35 male participants donned three different glove sizes during each test, including a best-fitting glove, a glove one size smaller than best-fitting, and a glove one size larger than best-fitting. For each glove size, gloves of two differing materials were tested, namely nitrile and neoprene. A barehanded condition was also tested, totalling seven gloved/barehanded conditions for each test. The seven conditions were assessed in a laboratory setting in a battery of tests. This consisted of components of task performance, including maximum pulling and pushing force, maximum torque, precision of force, tactility, speed and accuracy and dexterity. The performance responses were recorded, as well as participants’ perceptual responses using the Rating of Perceived Exertion scale, and muscle activity. Six muscles were selected: Flexor Digitorum Superficialis, Flexor Pollicus Longus, Extensor Carpi Ulnaris, Extensor Carpi Radialis, Flexor Carpi Ulnaris and Flexor Carpi Radialis. The results revealed that glove fit does affect certain spects of performance, and influences human operator responses for selected task components. Furthermore, discrepancies were distinguished between orking barehanded and working with an optimally fitted glove. There was also a glove material effect established. Overall, it was found that muscle activity when exerting maximum force in a pushing and pulling direction was optimal with the nitrile glove material. Maximum torque performance was enhanced with the use of a best-fitting glove, as compared with an ill-fitting glove or barehanded work. Force precision was preferable when barehanded, as opposed to the tactility task which rendered optimal results with a best-fitting glove. The same was found for speed and accuracy results, as glove fit appeared to have no effect on performance, but performance was improved when participants were barehanded. Dexterity performance was the most conclusively influenced by the conditions, resulting in barehanded performance being optimal. However, should a glove be necessary for a given task, an optimally-fitted glove which is of a thinner material would be recommended. It is necessary to distinguish the performance components of a task within industry and select the most appropriate glove for optimal performance and the least risk of overexertion.
- Full Text:
- Date Issued: 2010
The effects of hyperinflation on the Zimbabwean construction industry
- Authors: Moyo, Admire
- Date: 2010
- Subjects: Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9687 , http://hdl.handle.net/10948/1197 , Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Description: Less than two decades ago, Zimbabwe was a symbol for the rest of the world of what Africa could become (Dell, 2005). DiSilvio (2007) contends that independent Zimbabwe was an economic success on route to attaining status of the most “developed country” in Africa. Contrary to expectations, by 2003 the Zimbabwean economy was shrinking faster than any other economy in the world at 18 percent per year (Richardson, 2005). Reports indicate that the Zimbabwean economy is in crisis and has since been set back by more than 50 years (Matikinye, 2005). This phenomenon necessitated the need for an investigation to ascertain its cause in Zimbabwe. As a result, the research identifies and presents hyperinflation as the root cause of the crisis in Zimbabwe and illustrates the validity of this assertion with a focus on the Zimbabwean construction industry. As part of the research inquiry, a review of related literature was conducted. The literature review illustrated the generic effects of hyperinflation as well as the effects of this phenomenon in action in Zimbabwe. The literature study was followed by a questionnaire survey. The questionnaire was completed by 23 contractors and 7 clients from a census of contractors and clients in Zimbabwe. The questionnaire consisted of a number of variables, which the respondents were asked to rate vis-à-vis the effects of hyperinflation in the construction industry. In summary, the questionnaire sought to determine the causes of hyperinflation in Zimbabwe, its specific effects on the construction industry and how respondents thought the phenomenon could be mitigated so as to revive the Zimbabwean construction industry. The techniques of re-scaling, in conjunction with descriptive and inferential statistics, ranking and quadrant analysis were applied to the data. Results from these analyses revealed a high degree of agreement among respondents vis-à-vis the effects of hyperinflation on the Zimbabwean construction industry. The interpretation of the results further revealed that hyperinflation has undoubtedly led to the collapse of the Zimbabwean construction industry. In conclusion, the research, applying the interpretations of v the survey findings, prescribes a number of ways in which the Zimbabwean construction sector may be resurrected. Among the recommended prescriptions, there are a number of debatable issues that arise that the researcher proposes should be subject to future study.
- Full Text:
- Date Issued: 2010
The effects of point of substitution on the electrochemical behavior of new manganese phthalocyanines, tetra-substituted with diethylaminoethanethiol
- Authors: Akinbulu, Isaac Adebayo , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249137 , vital:51781 , xlink:href="https://doi.org/10.1016/j.ica.2010.06.003"
- Description: The syntheses and comparative studies of the spectral, voltammetry and spectroelectrochemical properties of new manganese phthalocyanine complexes, tetra-substituted with diethylaminoethanethio at the peripheral (complex 3a) and non-peripheral positions (complex 3b) are reported. Solution electrochemistry of complex 3a showed quasi-reversible metal-based (MnIIIPc−2/MnIIPc−2, E1/2 = −0.07 V vs. Ag|AgCl) and ring-based (MnIIPc−2/MnIIPc−3, E1/2 = −0.78 V vs. Ag|AgCl) reductions, but no ring-based oxidation. However, complex 3b showed weak irreversible ring-oxidation signal (Ep = +0.86 vs. Ag|AgCl). Reversible metal-based (MnIIIPc−2/MnIIPc−2, E1/2 = −0.04 V vs. Ag|AgCl) and ring-based (MnIIPc−2/MnIIPc−3, E1/2 = −0.68 V vs. Ag|AgCl) reductions were also observed for complex 3b. Spectroelectrochemistry was used to confirm these processes. Reduction process involving the metal (MnIIIPc−2/MnIIPc−2) was associated with the formation of manganese μ-oxo complex in complex 3a.
- Full Text:
- Date Issued: 2010
The effects of point of substitution on the formation of manganese phthalocyanine-based molecular materials
- Authors: Akinbulu, Isaac Adebayo , Khene, Samson , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249103 , vital:51778 , xlink:href="https://doi.org/10.1016/j.tsf.2010.08.145"
- Description: Molecular films of manganese phthalocyanine (MnPc) complexes, tetra-substituted with 2-diethylaminoethanethio at the peripheral (Mn(OAc)-β-TDEAETPc, 1) and non-peripheral (Mn(OAc)-α-TDEAETPc, 2) positions were formed on glassy carbon electrode by electropolymerization and electrodeposition respectively. Atomic force microscopy images confirmed the presence of the films and revealed significant morphological differences. The films exhibited an electrocatalytic activity towards the oxidation of the insecticide, bendiocarb. Hydrodynamic technique, using rotating disc electrode voltammetry, was used to investigate the kinetics of electro-oxidation of the insecticide. Morphological differences of the films significantly influenced kinetic parameters. Values of Tafel slopes, obtained from Tafel plots, suggested that catalysis of bendiocarb occurred via outer sphere mechanism.
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- Date Issued: 2010
The evaluation of environmental reporting by publicly listed South African banks
- Authors: Oduro-Kwateng, George
- Date: 2010
- Subjects: Environmental reporting -- South Africa Banks and banking -- South Africa Social responsibility in banking -- South Africa Social responsibility of business -- South Africa Environmental protection -- South Africa Environmental economics -- South Africa Economic development -- South Africa -- Environmental aspects Environmental management -- South Africa Climatic changes -- South Africa Coalition for Environmentally Responsible Economies Global Reporting Initiative Standard Bank Limited Nedbank ABSA Bank
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:740 , http://hdl.handle.net/10962/d1003860
- Description: Recently, bankers have come to realise that banking operations, especially corporate lending, affect and are affected by the natural environment and that consequently, the banks might have an important role to play in helping to raise environmental standards. Although the environment presents significant risks to banks, in particular environmental credit risk, it also perhaps presents profitable opportunities. Stricter environmental regulations have forced companies to invest in environmentally friendly technologies and pollution control measures and in tum generated lending opportunities for bankers. This research examines the corporate practices of three of the four dominant banks in South Africa with respect to the environment, focusing on issues of climate change and environmental risk management by way of reporting and disclosure to all stakeholders. The emphasis on environmental reporting by South African banks has been reinforced by the latest release of the King III Report on Corporate Governance in South Africa. Global governance requires that the triple-bottom line should be applied in all corporate undertakings due to globalisation and trade liberalisation; however, the banking sector has responded poorly to the clarion call. The false view that the banks have no significant relationship with environmental degradation is being disproved. Environmental management is a huge and massive reconstruction of what has gone wrong with nature by human influence. The South African banks have had to face with the challenging tasks of reporting on the direct and mostly the indirect impacts of their environmental activities. Based on the three sampled banks which incidentally had greater percentages of the market capitalizations, the banks have fairly performed in environmental reporting. For example, Standard Bank (SA) Ltd has just signed the Equator Principles in 2007 implying corporate lending was done in 2007 without any respect to environmental impact assessments by corporate borrowers. Consequently, environmental reporting was not done to facilitate informed decision-making by stakeholders mostly shareholders and the communities where borrowers tun businesses. The objective of this research study is to investigate the extent and quantity of/voluntary environmental disclosures in the annual and sustainability reports of the banks listed on Johannesburg Stock Exchange. The periods examined were those subsequent to the release of the Exposure Draft Coalition for Environmentally Responsible Economies (CERES) Global Reporting Initiatives (GRI) issued in 1999. Using content analysis to focus on the environmental aspects, the research study compared three annual reports and three sustainability reports of 2007 year for the three sampled banks in order to evaluate reporting practices in the period surrounding this intervention. The results suggest a trend to triple bottom-line reporting and the extent and quantity of environmental information, albeit in specific categories.
- Full Text:
- Date Issued: 2010
The experience of instant messaging upon adolescent female relationship
- Authors: Eberhardt, Antoinette
- Date: 2010
- Subjects: Adolescent psychology -- South Africa , Instant messaging -- South Africa , Friendship in adolescence -- South Africa , Teenage girls -- Social networks , Social networks -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9877 , http://hdl.handle.net/10948/1324 , Adolescent psychology -- South Africa , Instant messaging -- South Africa , Friendship in adolescence -- South Africa , Teenage girls -- Social networks , Social networks -- Psychological aspects
- Description: Social Interaction Technologies (SIT) have broadened the horizon of communication in terms of the way people are able to communicate. It is now possible to interact with others across the world and engage in numerous activities ranging from dating to political movements, hobbies and even professions (Chigona, Chigona, Ngqokelela, & Mpofu, 2009). Adolescents and pre-adolescents especially are inclined to make use of SIT in their social lives with the most popular mode of communication, apart from email, being instant messaging (IM) (Brown, Mounts, Lamborn, & Steinberg, 1993; Bryant, Sanders-Jackson, & Smallwood, 2006; Madden & Rainie, 2003). Adolescents tend to use IM regularly as a tool to maintain relationships and girls especially, use it as a tool to socialise (Jennings & Wartella, 2004; Lenhart, Rainie, & Lewis, 2001). The mobile phone or cell phone, which is another example of an SIT-based communication, has become an established medium of technical, social and commercial communication in South Africa. It has given rise to the development and vast growth of a mobile youth culture who consider it an essential tool for communicating (Bosch, 2008). In South Africa, instant messages may be sent via mobile phone using one of two methods: MXit and the SMS (short messaging service). MXit and the SMS are considered convenient tools of communication as an ongoing conversation in the form of a text message may be maintained in the present (Yoshii, Matsuda, Habuchi, Dobashi, Iwata, & Kin, 2002).
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- Date Issued: 2010
The fatigue life cycle prediction of a light aircraft undercarriage
- Authors: Erasmus, Daniel Jacobus
- Date: 2010
- Subjects: Metals--Fatigue
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9614 , http://hdl.handle.net/10948/1527 , Metals--Fatigue
- Description: The reliability of systems relies heavily on accurate fatigue life prediction of related components. Fatigue life prediction is a complicated process requiring the correct methodology to determine accurate and reliable predictions. The Palmgren – Miner damage accumulation hypothesis is widely used in determining the fatigue life of components exposed to variable loading conditions. Modifications have been made to this hypothesis trying to achieve a greater degree of accuracy, of these the Liu – Zenner modification has been the most successful. In this report the systematic process of fatigue life prediction using the Liu – Zenner modification to achieve reliable results is calculated. A representative stress time history measured in service on the component forms the basis for defining a flight cycle which is the chosen unit in which to express the fatigue life. Rainflow cycle counting performed on the stress time history allowed the formulation of a load spectrum to which the component is exposed in one cycle. Combining the load spectrum with the developed SN curve of the component and using the Liu – Zenner modification to the Palmgren – Miner rule a reliable fatigue life in cycles is predicted.
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- Date Issued: 2010
The feasibility of the Uitenhage provincial hospital private initiative
- Authors: Cherry, Jacqueline Helen
- Date: 2010
- Subjects: Public health administration -- South Africa -- Uitenhage , Health care reform -- South Africa -- Uitenhage , Feasibility studies -- South Africa -- Uitenhage , Hospital care
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8619 , http://hdl.handle.net/10948/1508 , Public health administration -- South Africa -- Uitenhage , Health care reform -- South Africa -- Uitenhage , Feasibility studies -- South Africa -- Uitenhage , Hospital care
- Description: The South African Health Care environment is in state of reform. Government strategy and change in legislation have been the catalyst for the development of new business models in South Africa. This report deals with the feasibility of a proposed model which is to be implemented by the Eastern Cape Department of Health at the Provincial Hospital in Uitenhage. The fundamental challenge in South Africa is the shortage of resources to support the health care industry from a public perspective. The point of departure for this research was to understand the complexity of this industry and investigate models that have evolved in South Africa and internationally. The literature research covers funding mechanisms from both a public and private perspective and takes into account the role the government plays in providing equitable health care for all. The literature provided the foundation to develop the model which is to be piloted at the hospital in Uitenhage. In terms of the research objective, a single case study methodology approach was conducted. Triangulation technique was used to gain insight from different perspectives and to test the model for validity. The core of this research focuses on the viability of the proposed model and the integration of this into the government health reform plan. The research revealed that in comparison to the existing PPP models in South Africa, this model is feasible. As a result of the analysis and the development of the proposed model, the research is concluded by offering suggestions for further research.
- Full Text:
- Date Issued: 2010
The Fishes of Zimbabwe and their Biology
- Authors: Marshall, Brian
- Date: 2010
- Subjects: Estuarine fishes -- Zimbabwe , Estuarine fishes -- Africa, Southern , Fishes -- Africa, Southern -- Identification , Estuaries -- Africa, Southern
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/167948 , vital:41524
- Description: The first comprehensive book on the fishes of Zimbabwe appeared in 1961 and was written by Rex Jubb. He followed it with a major treatise on the fishes of southern Africa published in 1967. These books were published at a time when interest in fishes – partly stimulated by the creation of Lake Kariba –was growing, and they were welcomed by anglers and scientists alike. Zimbabwean ichthyology progressed rapidly during the years following their publication and knowledge about our fishes grew steadily. New insights and understanding of their systematics led to numerous taxonomic revisions, bringing with them inevitable changes to their scientific names. At the same time increased collecting meant that new species were being added to the Zimbabwean list. By the early 1970s Jubb’s books had become outdated and there was a clear need for a new volume on the fishes of this country. The National Museums and Monuments met this need by publishing Graham Bell-Cross’ The Fishes of Rhodesia in 1976. This book was available at a remarkably low price and such was its popularity that it was soon out of print. It rapidly became outdated as well and was revised by John Minshull as the Fishes of Zimbabwe, published in 1988. This version had a number of new features such as the inclusion of exotic species and species discovered in the country since 1976, as well as name changes brought about by new developments in taxonomy. It, too, was available at a very low price and has proved to be very popular; the demand was so great that it was reprinted without alteration in the 1990s. By this time, however, it had also become outdated and there was a need for yet another revision, or for a completely new type of book. I have chosen the latter option in preparing this book, since there seemed little point in attempting to revise the earlier ones within their original format. I felt that it would not be desirable to produce another field guide type of book that would have to compete with Paul Skelton’s superb volume, A Complete Guide to the Freshwater Fishes of Southern Africa, first published in 1993, with a second edition eight years later. Instead, I decided that I should try to summarise the existing data about fishes in Zimbabwe. My dealings with students and inexperienced fish biologists has made it clear that many of them do not know what work has been done, or not done, on Zimbabwe’s fishes and they are not familiar with the literature. Much of it is, in any case, to be found in obscure publications that are not readily available in Zimbabwean libraries, which have declined in recent years and no longer subscribe to major international journals or even to local ones. This makes it very difficult to keep up with information or to track it down. I am aware, of course, that such a book will never be complete and may already be outdated at the time of its publication, but I hope that it will supply the basic background information for anyone interested in Zimbabwean fishes and provide a platform from which further studies can be launched. Wherever possible, I have used only data from Zimbabwe, although there may be an extensive literature from other countries for widespread or economically important species, such as Clarias gariepinus or Oreochromis mossambicus. This was a conscious decision because I wanted to summarise what is known about the fish in this country, so that other workers can assess what still needs to be done. Nevertheless, I have used some data from outside Zimbabwe, especially for fish from the upper Zambezi because of its relevance to our situation. As far as possible I have tried to use only published works as references, with the exception of university theses and some institutional reports, since most unpublished work is generally difficult to locate and ephemeral. The scientific names of fishes often change as systematic knowledge advances and the reader will note that there have been many changes since Bell-Cross & Minshull (1988) was published. Common names are a problem because of local variations and anglers in particular have various names (or nicknames) for popular angling species; I have used the standard names with these other names included in brackets where necessary.
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- Date Issued: 2010
The gap between what 'ought' to be and what students want
- Authors: Boshoff, Priscilla A
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70812 , vital:29747
- Description: There’s no curriculum! There’s no curriculum!” The young man in the focus group was so frustrated that he had to repeat himself, not just once, but several times. I had just asked the group what their feelings were about their second-year coursework. His sentiments were echoed by many of the students in the group, all of whom had passed the rigorous application process into second year at Rhodes University’s School of Journalism and Media Studies.
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- Date Issued: 2010
The genus Boccardia (Polychaeta: Spionidae) associated with mollusc shells on the south coast of South Africa
- Authors: Simon, Carol A , Worsfold, T M , Lange, Louise , Sterley, Jessica A
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:6873 , http://hdl.handle.net/10962/d1011620 , http://dx.doi.org/10.1017/S0025315409990452
- Description: Three species of Boccardia (B. polybranchia, B. pseudonatrix and B. proboscidea) were associated with mollusc shells on the south and south-east coasts of South Africa. Boccardia polybranchia was widely distributed along the coast and falls within the known distribution range of this species. Comparisons with material from other, international, locations showed that some specimens have been misidentified. No characters could be found to characterize distinct species for different regions within the range of B. polybranchia, as currently recognized. Boccardia pseudonatrix was found only at the most eastern site, increasing its known distribution range. Boccardia proboscidea, a non-indigenous species, was found only on abalone farms and was most abundant in the west.
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- Date Issued: 2010
The geochemistry and evolution of Palaeogene phonolites, central Namibia:
- Authors: Marsh, Julian S
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145000 , vital:38399 , https://doi.org/10.1016/j.lithos.2010.02.012
- Description: Phonolites of Palaeogene age occur at two different localities in central Namibia, occurring as clusters of eroded monogenetic lava domes. Six phonolites at Aris collectively exhibit a narrow compositional range and represent a single magma system of highly evolved phonolite with high concentrations of Na2O, Rb, Th, Zr, Zn, Pb, and REE and very low abundances of MgO, P2O5, Sr and Ba. No mafic rocks are associated with the Aris phonolites and their ultimate petrogenetic origin remains obscure. The more abundant Staalhart phonolites exhibit more variable but scattered compositional variation consistent with fractional crystallization dominated by sanidine (and nepheline) and pyroxene. The behaviour of REE is decoupled from Zr, Nb, and Th in this suite indicating a controlling role for minor phases in their evolution. The least evolved phonolites have initial 87Sr/86Sr 0.7043, which is identical to a small occurrence of associated plagioclase-bearing nephelinite indicating a possible petrogenetic link.
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- Date Issued: 2010
The geology of the Witteberg group, Cape supergroup, with specific focus on the Perdepoort member as a potential silica source
- Authors: Olivier, Wernich Corné
- Date: 2010
- Subjects: Geology -- South Africa -- Witteberg Group , Stratiography -- South Africa -- Witteberg Group , Silicate minerals -- South Africa -- Witteberg Group
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10660 , http://hdl.handle.net/10948/1386 , http://hdl.handle.net/10948/d1012889 , Geology -- South Africa -- Witteberg Group , Stratiography -- South Africa -- Witteberg Group , Silicate minerals -- South Africa -- Witteberg Group
- Description: Selected outcrops of the Upper Devonian to Lower Carboniferous, Witteberg Group, Cape Supergroup were mineralogically and structurally analyzed. The study area is located approximately 30km northwest of Kirkwood and 10km south of Darlington Dam, Eastern Cape, South Africa. Strata predominantly consist of arenaceous Witpoort Formation, which includes the Perdepoort, and Rooirand Members. The Perdepoort Member is a thinly bedded quartzite also known as the "white streak". The Rooirand Member quartzite is a highly iron stained red-brown quartzite. The dark-grey, pyritic rich shales of the Kweekvlei Formation overlie the Witpoort Formation in the southern half of the study site. These shales are highly deformed and display closely spaced thrust faults and close folds. The study area encapsulates a range of folding from tight to open folds. Faulting consists of low angle north verging thrust fault, south verging back thrusts, south and north dipping normal faults, and strike-slip faults. Closely spaced, fore-land verging thrusts faults predominate over hinterland verging back thrusts. Normal faulting post-dates thrust faulting and utilized weaknesses in axial planar cleavage and in certain instances existing thrust fault planes. Strike-slip faulting post-dates thrusting and has in places reactivated pre-existing thrust fault planes. Macro scale folding includes overturned synclines and large anticlines which have been eroded, exposing older strata. Fold axes plunge at low to moderate angles west-southwest. This correlates with tension gashes which indicate north westward directed forces. Eastward directed forces are confirmed by the presence of tension gashes and strike-slip movement. The local geology displays north westward directed compression followed by strike-slip movement. Normal faulting post-dates all other structures and is associated with the Mesozoic break-up of Gondwana. The Perdepoort Member was sampled along strike, at different outcrop latitudes. Seven samples were selected for scanning electron microscope analysis. Samples are composed almost entirely of quartz; accessories include, biotite, muscovite, sericite, baryte, and apatite. Epigenetic hematite is present along cracks within certain samples Epigenetic hematite occur along cracks with oxides and phosphates in the form of rutile, apatite and monazite present in a number of samples. When compared to other silica extraction operations the Perdepoort Member appears viable for explotation. However, for the solar cell industry the purity of this horizon is clearly far below that required for industy.
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- Date Issued: 2010
The Global Auction: the broken promises of education, jobs, and incomes
- Authors: Badat, Saleem
- Date: 2010
- Language: English
- Type: Text
- Identifier: vital:7786 , http://hdl.handle.net/10962/d1015941
- Description: Discussant: Hugh Lauder, University of Bath - Keynote Paper/Address: Economic Globalisation, Skill Formation and the Consequences for Knowledge Workers
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- Date Issued: 2010
The global financial crisis and its impact on the South African economy
- Authors: Madubeko, Vongai
- Date: 2010
- Subjects: Globalization -- Economic aspects , Global Financial Crisis, 2008-2009 , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11457 , http://hdl.handle.net/10353/363 , Globalization -- Economic aspects , Global Financial Crisis, 2008-2009 , South Africa -- Economic conditions
- Description: This dissertation investigates the effects of the financial crisis on the South African economy. In order to do this, an index which describes the financial conditions of the South African economy is constructed and computed. The index indicates that domestic South African financial conditions have deteriorated substantially during the period under study and so the study investigates how this has impacted on the country’s economic growth. A VAR model with South African variables is specified and used to assess the quantitative effects of the financial crisis on South African real GDP growth. Results suggest that the South African economy was not significantly affected by the crisis, but economic growth was slowed down and may still grow substantially slower in the next few years due to the financial crisis. These results corroborate the theoretical predictions and are also supported by previous studies.
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- Date Issued: 2010
The ichthyofauna and piscivorous avifauna in a small temporarily open/closed Eastern Cape estuary, South Africa
- Authors: Blake, Justin David
- Date: 2010
- Subjects: Estuarine fishes -- South Africa -- Eastern Cape , Bird populations -- South Africa -- Riet River Estuary , Estuaries -- South Africa -- Eastern Cape , Fish populations -- South Africa -- Riet River Estuary , Estuarine animals -- South Africa -- Riet River Estuary , Birds -- South Africa -- Riet River Estuary , Riet River Estuary (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5709 , http://hdl.handle.net/10962/d1005395 , Estuarine fishes -- South Africa -- Eastern Cape , Bird populations -- South Africa -- Riet River Estuary , Estuaries -- South Africa -- Eastern Cape , Fish populations -- South Africa -- Riet River Estuary , Estuarine animals -- South Africa -- Riet River Estuary , Birds -- South Africa -- Riet River Estuary , Riet River Estuary (South Africa)
- Description: The spatial and temporal patterns in selected components of the ichthyofauna and piscivorous avifauna in the small temporarily open/closed Riet River Estuary located on the eastern seaboard of southern Africa was investigated monthly over the period August 2005 to July 2006. The ichthyofauna within the littoral zone of the estuary was sampled using a 5 m seine net (8 stations) while a 30 m seine net (4 stations) was employed to sample the fish in the channel. Bird counts were made along repeat transects along the length of the estuary. Total ichthyofaunal abundances and biomass ranged between 1.60 and 8.67 individuals m⁻² and 0.45 to 21.76 g wwt m⁻² within the littoral zone, and between 0.08 and 0.44 individuals m⁻² and 0.58 and 36.52 g wwt m⁻² in the channel of the estuary. The highest values were generally recorded during the summer months. Results of the numerical analysis indicated that the breaching events recorded over the study period did not lead to a common trend in the ichthyofaunal community. In the absence of a link to the marine environment, the ichthyofaunal community in the littoral zone was numerically dominated by the estuarine resident species, Gilchristella aestuaria and to a lesser extent by Glossogobius callidus, which collectively accounted for ca. 54% of the total ichthyofauna sampled. The establishment of a link to the marine environment coincided with increased numbers of marine breeding species including Atherina breviceps and Rhabdosargus holubi to total fish counts within the estuary. Hierarchical cluster analysis did not identify any spatial patterns in the community structure of the ichthyofauna in the littoral zone or channel zone of the estuary, which could likely be linked to the absence of any distinct horizontal patterns in salinity and temperature within the system. A total of thirteen piscivorous bird species was recorded over the study period. Of the recorded species, six species were wading piscivores, four species were aerial divers and the remaining three species were pursuit swimmers. There were no significant correlations between the estimates of the ichthyofaunal abundance and biomass and bird numbers evident during the study (P> 0.05 in both cases). The Reed Cormorant (Phalacrocorax africanus) was the dominant species throughout the study, with a mean of 8.25 (SD ± 7.90) individuals per count. Mean values of the Pied Kingfisher (Ceryle rudis) and Giant Kingfisher (Megaceryle maximus) were 3.42 (SD ± 1.20) and 1.17 (SD ± 0.60) individuals per count, respectively. The remaining species revealed mean values < 0.5 individuals per count. The highest bird numbers were recorded in winter reflecting the migration of large numbers of the Reed Cormorant into the system. Breaching events were associated with a decrease in total bird numbers, which was most likely due to loss of potential foraging habitat (littoral zone) for waders resulting from reduced water levels. Monthly food consumption by all piscivorous birds revealed large temporal variability, ranging from 26.35 to 140.58 kg per month. The observed variability could be linked to mouth phase and bird numbers.
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- Date Issued: 2010
The identification and evaluation of key sustainable development indicators and the development of a conceptual decision-making model for capital investment within Gold Fields Limited (GFL)
- Authors: Jacobs, Phillip A H
- Date: 2010
- Subjects: Industrial management -- Environmental aspects -- South Africa -- Case studies Social responsibility of business -- South Africa -- Case studies Environmental protection -- South Africa -- Case studies Sustainable development -- South Africa -- Case studies Business ethics -- South Africa -- Case studies Industries -- Social aspects -- South Africa -- Case studies Industries -- Moral and ethical aspects -- South Africa -- Case studies Gold Fields Ltd -- Case studies
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:820 , http://hdl.handle.net/10962/d1008304
- Description: The current trends in sustainable development (SO) were examined in this study, which brought about the realisation that SO has become a business imperative. Mining, which is a highly impacting industry, is faced with the dilemma of implementing the principles of SO despite the realisation that its activities are severely limited by· the finite nature of the resource it is capitalising on. This reality, however, does not detract from the non-negotiable requirement for the industry to meet the increasing pressures to act responsibly towards the environment and the community in which it operates. Gold Fields has stepped up to the plate and has already taken several steps to achieve this end. These include the adoption of SO in its Vision, Values and strategies and the development and implementation of a SO framework to ensure the integration of the principles of SO into the business. Furthermore, Gold Fields has also entered into voluntary activities that further cement the commitment the company has towards so. These other initiatives include, inter alia, its International Council on Mining and Metals membership, UN Global Compact participation, becoming a signatory to the cyanide code, IS014001, and so on. This study focussed on several indicator categories and the identification of a set of supporting sustainable development indicators (SOls) for each, which included environmental, social, economic, technological, and ethics, legal and corporate governance (not in order of priority). These indicators were assessed by a carefully selected group of respondents whose collective wisdom and expertise were used to identify and weight supporting SOls for each of the indicator categories. These supporting SOls were in turn used to develop a model that is able to assist in the business's decision making processes when capital investment is being considered . A water treatment project that is currently being considered by Gold Fields was utilised to demonstrate how the decision making model can be applied to two different scenarios. The result clearly and successfully demonstrated that by proactively taking environmental, economic, social, technological, and ethics, legal and corporate governance considerations into account, a gold mining company is able to increase the level of SO of a capital investment project.
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- Date Issued: 2010
The identification of factors that contribute to the creation of a formal mentoring programme at Lumotech (Pty) Ltd
- Authors: Taljaard, Arno
- Date: 2010
- Subjects: Mentoring in business -- South Africa , Employees -- Coaching of -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8683 , http://hdl.handle.net/10948/1121 , Mentoring in business -- South Africa , Employees -- Coaching of -- South Africa
- Description: Introduction: At the time of this study, Lumotech (Pty) Ltd did not have a formal mentoring programme. This study evaluated the requirements of such a programme in order to formulate an implementation strategy. Rational: The main research problem addressed in this study was to identify the factors that contribute to creating a formal mentoring programme at Lumotech (Pty) Ltd. To achieve this objective, sub-problems were identified and addressed. The sub-problems identified were addressed through a literature review, an empirical study and the formulation of a strategy for the implementation of a formal mentoring programme. Goals/Objectives: This paper attempts to create a strategy for implementing a formal mentoring programme at Lumotech by answering a series of research questions.
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- Date Issued: 2010