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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

An evaluation of formal mentoring programmes within two South African organisations

Shelton, Delyse Elizabeth January 2006 (has links)
The benefits of informal mentoring are numerous and organisations have recognised these benefits in terms of organisational development. There has been an attempt to harvest these benefits through the introduction of formal mentoring programmes as a tool to fast track and then ultimately retain internal capability. This research on formal mentoring programmes occurred within a qualitative paradigm and data was obtained through document analysis and interviews from five mentoring pairs in one organisation and four mentoring pairs in another. The data was then presented and analysed in terms of the models proposed in the literature. The aim of this research was to evaluate formal mentoring programmes within South African organisations based on a framework provided by the literature. It was found that the literature proposed no formal evaluation model and thus, one was developed based on models of programme evaluation and formal mentoring implementation models. On the evaluation of the two formal mentoring programmes, it was found that there are some issues raised in the literature that are pertinent to both organisations but that there were also issues that were only relevant to one of the programmes. According to the research the differences in perceived success of the mentoring programme lay in the goals of the programme relating to the broader goals and culture of the organisation. It is recommended that future research investigate the impact of organisational culture on the effectiveness of formal mentoring programmes. The research also identified a need for supportive resources although this study did not assess the appropriateness and sufficiency of the resources. Organisations also need to implement effective evaluative practices in order to implement effective changes to the programme.
62

Grammatical constraints and motivations for English/Afrikaans codeswitching: evidence from a local radio talk show

Bowers, Diane Lesley January 2006 (has links)
Magister Artium - MA / The study investigated the practice of codeswitching within the Cape Flats speech community of Cape Town. Members of this speech community have always been exposed to both English and Afrikaans in formal as well as informal contexts. Due to constant exposure to both languages, as well as historical and political experiences, members of the speech community have come to utilize both languages within a single conversation and even within a single utterance. Codeswitching is an integral part of the community's speech behaviour. The main purpose of this research was to uncover and analyze the motivations behind codeswitching in the bilingual communities of Cape Town, while also providing a strong argument that codeswitching patterns evident in their speech do not always correspond completely with linguistic constraints that are regarded as 'universal'. / South Africa
63

A study of kitsch in South African suburban society

Page, Lindsay Ann January 1984 (has links)
Consider the possibility of the remnants of our present day society being excavated and studied in centuries to come. Imagine the craftsmanship, the art, artifacts and architecture that will then be compared to those of the past centuries. Our entire culture will be labelled by the endless array of rubbish that has become an integral part of our lives. The increasing prevalence of kitsch in the society goes almost unnoticed where it should be causing concern. Few people are aware of its existence, or the permanent aesthetic scars induced by this prevalence. How has this cult of sheer awfulness come about and why has it become prevalent? It is impossible to pursue all the avenues of kitsch - so vast is it but it is the purpose of this study to try and answer some of the questions, in order to make people more aware of what has crept into our society, to help them become more discriminating, and not merely to level criticism at the perpetrators of kitsch.
64

Water quality, abalone growth and the potential for integrated mariculture on a South African abalone Haliotis midae L. farm

Yearsley, Rowan David January 2008 (has links)
Abalone Haliotis midae farming in South Africa is highly intensive, employing pump-ashore, flow-through systems. Despite the known sensitivity of abalone to water quality, there is only a rudimentary understanding of water quality dynamics on South African abalone farms and its effects on abalone production. Furthermore, the potential for reusing the relatively dilute abalone farm effluent to culture other animal species has not been investigated. This study investigated the dynamics of water quality and growth on a South African abalone farm and assessed the suitability of the effluent for the culture of silver kob Argyrosomus inodorus and bloodworm Arenicola loveni loveni. Monitoring of water quality and abalone growth in abalone tanks revealed that oxygen concentrations decreased, while H⁺ ion and free-ammonia (NH₃) concentration increased in a gradient between the inflow and outflow. Abalone growth was positively correlated with oxygen concentration and negatively correlated with free-ammonia and H⁺ ion concentration. The oxygen (O) concentration of the farm influent was dependent upon the influents’ temperature (T) and was described by the relationship O (mg L⁻¹) = 11.244 – 0.208T (r²=0.74). Linear regression analysis of data collected from abalone farm tanks revealed that the concentration of total ammonia at the outflow of abalone tanks (μg TAN L⁻¹) was dependant upon temperature (°C), flow-rate (L s⁻¹ kg⁻¹ H. midae), abalone size (g) and length of time since the tank was last cleaned (d) (n = 125, r² = 0.80). The production of total ammonia (μg TAN s⁻¹ kg⁻¹) was related to temperature, abalone size and days that the tanks remained un-cleaned (n = 125; r² = 0.81). A diurnal cycle of respiration was evident in abalone tanks with higher oxygen consumption and H+ ion production at night. The oxygen concentration of farm effluent was related to temperature, farm biomass and flow rate by means of a linear regression equation (n = 40; r² = 0.69). The results demonstrated the importance of optimising the flow-rate per unit of biomass for various temperatures and sizes of abalone. As abalone size and temperature cannot be controlled under farm conditions, the flow-rate per unit of biomass which the abalone culture system receives will determine the quality of the culture water. The specific growth rate (0.48 ± 0.01 % BW d⁻¹), mortality (1.8 ± 0.5 %), feed conversion ratio (3.0 ± 0.2) and protein efficiency ratio (1.0 ± 0.1) of silver kob kept in either abalone farm effluent or control seawater for 120 days did not differ significantly (t-test, P>0.05). A 90 day growth trial indicated that abalone farm effluent is a suitable culture medium for bloodworm. Bloodworm supplied with control seawater lost weight at 0.19 ± 0.04 % BW d-1, while those given abalone effluent grew at 0.39 ± 0.07 % BW d⁻¹. Mortality was 6 ± 3 % in effluent and 11 ± 8 % in seawater. The bloodworm were efficient at processing solid waste. Abalone farm effluent initially contained 7.7 ± 13 mg L⁻¹ more suspended solids than control seawater, which contained 3.5 ± 0.5 mg L⁻¹, but after passing through bloodworm systems the concentration in abalone effluent was reduced to only 1.4 ± 3.5 mg L⁻¹ above that in control seawater. Therefore, abalone farm effluent could be reused as a culture medium for both silver kob and bloodworm. Future work is needed to investigate aspects of the feasibility of such systems such as growth rates at different sizes and stocking densities.
65

What future graduates will value in their leaders: a study across gender and culture

Cox, Andrea January 2013 (has links)
Effective leadership has been found to be a key determinant of organisational success. Effective leadership does not only involve the ability to influence and inspire others, it is the ability to lead subordinates according to the competencies that they value. The focus of this study is on determining what in fact the future South African graduate workforce will value in a leader. Effective leadership and the competencies that subordinate's value is especially relevant today as leadership is forced to contend with an increasingly diverse workforce. This diversity necessitates the need for a leadership style to be congruent with what subordinates of diverse genders and cultures will value, so to be effective. Existing studies have indicated that gender and culture influence what subordinate's value in a leader, however it is evident from the results of this study, that this is not entirely the case. Regarding gender, the female and male respondents in this study value similar competencies in their leader, indicating that there is no distinct set of competencies that will be valued by male and female graduates. With respect to culture, the respondents value a mixture of competencies that combine both African and Western leadership practices, values and philosophies, indicating that there is no distinct set of competencies that will be valued by African, Coloured, Indian and White graduates. On the basis of this research, the recommendation is that for leaders to be effective in the 21 st century, a leader must be loyal and inspirational, have vision and integrity and lastly must be open and honest with their subordinates
66

The ecology of juvenile Rhabdosargus holubi (Steinachner) (Teleostei : Sparidae)

Blaber, Stephen J M January 1974 (has links)
INTRODUCTION: Estuaries have received considerable attention from biologists in southern Africa in the past thirty years. Professor J.H. Day and the Zoology Department of the University of Cape Town have undertaken ecological surveys of a large number of estuaries of a variety of types, laying the important groundwork for more detailed studies of single species or problems. Their studies showed that the fish populations of southern African estuaries consist mainly of marine species. Why and when these species enter or leave the estuaries and whether they grow or breed in them were not established. The only relatively detailed study of a fish in southern African estuaries was that of Talbot (1955) who investigated aspects of the growth, feeding and reproduction of Rhabdosargus globiceps (Cuvier). No quantitative information has been published on any of the fish species, perhaps due to the difficulty of obtaining such data; results such as population estimates, mortality rates and growth rates are particularly unreliable when the area being investigated is in direct contact with the sea. Studies relating to even a single species of fish are hampered by immigration and emigration between estuary and sea, which make the population continuously variable. The larger estuaries are also difficult to sample adequately, especially with regard to netting, except perhaps on a very large scale using expensive commercial equipment. Along the southern African coast many of the smaller estuaries with a limited catchment area are cut off from the sea for most of the year due to erratic rainfall and longshore drift of sand. These closed or 'blind' estuaries of south eastern Africa, of which there are at least thirty in the eastern Cape Province, provide excellent areas for studying estuarine fish populations which enter when the estuary is open to the sea, but become isolated once it closes. These fish which become cut off in closed estuaries are subject to a new series of conditions. They are exposed to the wider temperature and salinity fluctuations of an estuary and they are forced to utilise the food resources of the estuary. Additionally they may be subjected to predation from piscivorous birds, and those predatory fish which are also cut off in the estuary. These factors will affect the size, mortality, and growth rates of a fish population. Since the fish are isolated no recruitment from the sea can take place, and any increase in numbers would have to come from breeding within the estuary. It is inevitable that the most numerous species should receive attention first. Rhabdosargus holubi (Steindachner) (Synonomy : Sargus holubi Stndr, Austrosparus tricuspidens Smith, Rhabdosargus tricuspidens (Smith))(Plate 1) is one of the most abundant fish in the estuaries of the eastern Cape Province. According to Smith (1965) it is endemic to southern Africa, occurring from the Cape to Zululand, being most common between Mossel Bay and East London. It is largely replaced by Rhabdosargus sarba (Forskal) in the north of its range and by Rhabdosargus globiceps (Cuvier) in the south. Commonly called the 'flatty' or silver bream it is considered only as being of nuisance value by fishermen, seldom exceeding 30 cm in length. In this study the ecology of R.holubi was examined in relation to the closed West Kleinemond estuary which is a small 'blind' estuary typical of those found along the eastern Cape coast. The growth, mortality and population size of R.holubi in this estuary were investigated and linked where possible with predation and detailed studies into the tolerances, food, and feeding of the species. It was not known at the commencement of the study whether breeding could occur in estuaries, although Smith (1965) stated that R.holubi does breed in estuaries. During the course of the sampling programme in the West Kleinemond estuary, measurements of the growth and population structure of two other species of fish were recorded for comparison with R.holubi: the sparid Lithognathus lithognathus (Cuvier) (White Steenbras) and the piscivorous carangid Hypacanthas amia (L.) (Leervis or garrick). Laboratory studies on R.holubi were possible due to the fact that large numbers of this species could be caught in eastern Cape estuaries and transported to Grahamstown, where they could be maintained in captivity for up to four months in recirculating seawater aquaria. During the course of the study over 2000 fish were kept in captivity at different times for a variety of experiments. Another 2500 were preserved for gut analyses and lipid determinations, while over 5000 were captured, examined and released in the field.
67

The life history patterns of the polychaete, Terebrasabella heterouncinata, a pest of cultured abalone

Simon, Carol Anne January 2005 (has links)
Terebrasabella heterouncinata is a small K-selected sabellid polychaete. It is a simultaneous hermaphrodite with a semi-continuous mode of reproduction, producing relatively few large eggs that are brooded within the parental burrow until the larvae emerge, to settle on the growing edge of the abalone shell. Despite its low fecundity, this worm has become problematic on abalone farms in South Africa. The present study was conducted to gain an understanding of the life history patterns of T. helerouncinata to determine how they contributed to the success of these worms under altered conditions. This study demonstrated that conditions prevalent on abalone farms were conducive to enhancing the reproductive success of this worm, and suggests that larger, more fecund worms may have been selected for in the decade that these worms have been present on the farms. Increased nutrient availability, and possibly the increased stability of the farm environment relative to its natural environment, has led to a 1.5-fold increase in the average size of the worms. Body size was found to be positively correlated with brood size, and this resulted in worms on farms brooding 3 to 4.5 times more offspring at a time than worms from wild abalone. The ability to increase the number of eggs produced at a time may have been limited by the fact that these worms have only two ovaries. Thus, the increase in fecundity may have been related primarily to the increase in the rate at which the eggs were laid by the worms on the farms, and the increase in the coelomic space available for the storage of these rapidly developing eggs. The ability to increase the rate at which oocytes develop may be related to the vitellogenic mechanisms employed by these worms. Vitellogenic oocytes are able to incorporate high molecular weight yolk precursors from the surrounding coelomic fluid through endocytotic activity. This may allow the oocytes to increase the rate at which they incorporate yolk material under conditions of nutrient enrichment. The increase in fecundity did not occur at the expense of offspring size and, presumably, quality. The increased reproductive output on the farms was compounded by a proportionate increase in the number of reproducing worms within the population. In addition, these worms are long-lived (worms from farmed abalone reached a maximum age of approximately 40 months) and exhibit negligible senescence. Thus, their reproductive output did not change significantly with an increase in age. Furthermore, the proportion of the reproductive worms did not decrease with an increase in age. Thus, within the age range tested, worms of all ages have the potential to make equal contributions to population growth. While diet and abalone stocking density could not be identified as having a significant effect on reproductive output and infestation rate under intensive culture conditions, it was demonstrated that in a naïve abalone population, the total intensity of infestation increased exponentially with time. This increase may be a consequence of an increase in fertilisation success. These worms continuously produce entaquasperm that are released into the water column. The sperm are collected by other individuals that then store the sperm in a single spermatheca. The ability to store sperm relieves individuals of a dependence on the synchronisation of spawning of eggs and sperm. As the population size and density increases, there could be more individuals releasing sperm into the water column, resulting in a continuous supply of sperm. The increased production of eggs would therefore not be constrained by a lack of sperm. The stored sperm are released into the brood chamber to fertilise eggs as they are laid, and this would probably increase the fertilisation success in the species. This study also provides evidence to suggest that reproduction in this worm has a seasonal component. Future studies should concentrate on measuring fertilisation success in greater detail, measuring the effect of season on reproduction, determining whether there are genetic differences between worms on farmed and wild abalone and determining whether wild worms have similar life-spans and age-related fecundity as worms on farms.
68

The protein and energy requirements of the South African abalone, Haliotis midae

Green, Alistair John January 2009 (has links)
The abalone (Haliotis midae) culture industry in South Africa is becoming increasingly dependent on the use of formulated feeds, due to limitations in the supply of kelp. The bulk of the feeds that are currently available were developed based on the requirements of juvenile abalone cultured within the optimal temperature range for growth (18 - 20 °C). However, most abalone farming facilities are land-based pump ashore operations and are thus mostly exposed to temperatures outside of this range. In addition, these feeds have been found to be unsuitable for abalone cultured at elevated water temperatures (> 20°C). The aim of the study was to develop size and temperature specific diets for H midoe through optimisation of dietary protein, energy and lipid levels. Abalone were cultured under farm-like conditions in three partially recirculating temperature controlled systems at either 18, 22 or 24°C and fed formulated diets containing graded levels of protein (18,22 and 26 %) and energy (11.6, 13.5 and 16.2 MJ.kg·I ). Abalone were stocked into baskets at 5 % of available of surface area (n=36) and each diet (n=9) was fed to four baskets of abalone at each of the three temperature regimes for ten weeks. Abalone growth was temperature dependent, with growth declining from 4.33 g.month-I for abalone cultured at 18°C to 0.77 g.month-I at 24°C. Dietary protein could be reduced from 26 to 18 % provided dietary energy levels were maintained at 13.5 MJ.kg- l • A dietary energy level of 11.6 MJ.kg-1 was insufficient to meet the energetic requirements of H midae regardless of the protein content of the diet. The effects of water temperature and body size on the protein requirements of H midae were investigated by culturing abalone at temperatures within the optimal range for abalone farming (i.e. 14, 16 and 18°C). Three size classes of abalone (15, 50 and 80 mm) were fed formulated feed containing graded levels of dietary protein (20, 26, 32, 38 and 44 %) under controlled laboratory conditions for 12 weeks, and, in a separate experiment, under commercial farm conditions for 24 weeks. It was not possible to convincingly define the optimal protein levels for abalone of different sizes in this experiment because growth rates fell below average commercial growth rates obtained on farms. Growth was temperature dependent in the laboratory trial, with the rate of weight gain of the 15 mm (ANOV A: p=0.002) and 50 mm abalone (ANOV A: p=0.02) increasing significantly with an increase in temperature from 14 to 18°C. In the farm trial, dietary protein content did not affect the growth rate of the 10-15 or 80 mm abalone (ANOVA: p>0.05), however, the 50 mm abalone displayed significantly higher weight gain on the 32 % (4.72±0.20 g.month-I ) and 38 % (5.01±0.34 g.month-I ) protein diets compared to those fed the 20 % protein diet (3.75±0.13 g.month-I ) (ANOVA: p=O.OI). Although definition of optimal dietary protein levels were not possible, the effects of dietary protein content and water temperature on the growth of H midae were independent signifying that the protein requirements of abalone are temperature independent. In addition, there was no evidence to indicate that abalone of the different sizes tested here had different dietary protein requirements. The size specific dietary lipid and protein requirements of H midae were investigated by feeding two size classes of abalone (30 and 60 mm initial shell length) diets containing graded levels of dietary lipid (4, 7, 10, 13 and 16 %) and protein (34 - 39 %) for 12 weeks. The 30 and 60 mm abalone were stocked at 7 (n=200) and 9 % (n=36) of the available basket surface area respectively and each diet was fed to four baskets of abalone of each size class. The protein requirements of H. midae are influenced by the amount of available dietary energy and thus it is possible that the ability of abalone to utilise lipids as a source of energy differs in the presence of varying levels of dietary protein. High levels of dietary lipid negatively affected the growth, condition factor and soft tissue glycogen content of both size classes of abalone. This negative effect was greater in the 30 mm size class compared to the 60 mm abalone. The corresponding increase in feed consumption and feed conversion ratio in response to increasing levels of dietary protein also provides evidence that abalone are unable to utilise dietary lipids as an energy source and high levels of dietary lipid probably inhibit the uptake of carbohydrates and protein. High dietary lipid levels did however appear to promote gonad maturation. It was possible to reduce dietary protein from 34 to 20 % without negatively affecting growth through the maintenance of dietary energy levels and thus it is recommended that future experiments on the energy content of formulated feeds should focus on the improved use of carbohydrates. Reductions in the protein portion of formulated feeds for H. midae are possible provided the diet contains sufficient levels of energy supplied from carbohydrates. As the ability of abalone to utilise dietary lipid is limited, lipids are unlikely to play a significant role as an energy source in abalone feeds. Further investigations should focus on the utilisation of various carbohydrate sources in abalone feeds.
69

Fungal and substrate-associated factors affecting lignocellulolytic mushroom cultivation on wood sources available in South African [i.e. Africa]

Da Serra, Maria Fatima January 1997 (has links)
Vast- quantities of lignocellulosic materials, representing potential substrates for the cultivation of speciality mushrooms, are produced annually in South Africa. A number of these materials are derived as waste products of the timber and agricultural industries, e.g. Maranti (Shorea spp.) and Port Jackson Willow (Acacia longifolia) respectively. The screening of various wood-degrading fungi, which are cultivated worldwide for their production of speciality mushrooms, indicated that under the environmental conditions considered, certain species were adapted to cultivation on these lignocellulosic wastes (Pleurotus species) whereas others were not (Lentinus edodes and Flammulina velutipes). Furthermore, intra- and interspecies specific differences in the growth and production potential of the various lignocellulolytic fungi investigated on synthetic and natural medium were discovered. Biochemical and genetical investigations of these strains indicated differences between and within species which were often significant. Species varied qualitatively and quantitatively in the lignocellulolytic enzymes produced, which was loosely correlated with productivity on the different media investigated. Genetical studies, using RAPD fingerprinting, indicated that the Pleurotus genus is highly variable which supports the observed differences in growth, yield and enzymatic activity between different strains and species.
70

The importance of managing cultural change in the succession process within family businesses in the Gauteng area

Hynd, Dale Vaughan January 2003 (has links)
The aim of this research was to ascertain the implications and the impact that the succession process would have on the organisational culture of family businesses. In an attempt to answer this, the researcher asked three questions surrounding the succession process and its relationship with organisational culture. The questions related to the extent to which the family business was prepared for change in management; what changes occurred before, during, and immediately after the succession process, and what results these changes had on the organisational culture. Family businesses account for a large proportion of the national and global market activities, and so it is imperative that attention be paid to any problems they may experience. As it is, family businesses have difficulty in successions, with roughly one third of first generation family businesses surviving the succession process. It is the aim of this research to explore the contribution organisational culture has in the large failure rate of succession with family businesses. When successors enter into the organisation, they bring with them different perspectives on managerial issues suggesting that a change in leadership style will occur as a result of a succession. In answering the research questions, the researcher embarked on a two-phase research methodology utilising a quantitative and qualitative process. This triangulation process incorporates a self-administrated survey questionnaire, and six in-depth interviews. The survey questionnaire and interview schedules were structured using a combination of elements obtained from Harris's (1998) and Levinson's (1972). The survey data was analysed using various statistical methods, predominantly a Factor Analysis, where as Abstract iii the interviews were analysed using a theme retrieval process. The two processes were combined to yield the results. The findings of the research conclude that through the introduction of the successor in the change process, a new leadership style is introduced into the business. The new leader changes policies, practices and procedures, which are related to organisational climate and are the tangible aspects of organisational culture. Altering the climate essentially alters the culture, which may result in anxiety within the organisation and lead to tension. If these issues are not addressed, they may result in the demise of family businesses.

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