Geotectonic controls on primary diamond deposits : a review of exploration criteria
- Authors: Hannon, Camille
- Date: 2013-05-23
- Subjects: Diamonds , Geology, Structural , Diamond deposits , Kimberlite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5047 , http://hdl.handle.net/10962/d1007810 , Diamonds , Geology, Structural , Diamond deposits , Kimberlite
- Description: The origin of diamonds, their preservation and transport to the surface have been important issues over the last decades after the acknowledgement that diamonds are xenocrysts in the host kimberlites and after the discovery of new transport media such as lamproites. Different types of diamonds -E-type diamonds, P-type diamonds- and different types of hosts - Eclogites, Peridotites- have been distinguished. Each type corresponds to particular formation criteria. Ecogitic Diamonds are mostly related to subduction processes, whereas more uncertainties remain regarding the formation of Peridotitic Diamonds. Komatiite extraction and subduction of graphite-bearing serpentinites have been proposed as the more likely processes involved in their formation. A typical mantle signature for diamonds implies a thick, cool, reduced lithosphere. The keel-shape model is the most popular. Archaean cratons are therefore the most promising exploration target and area selection will expect to follow the Clifford's Rule. However, the evidence of cratonic areas hidden under younger formations · through seismic profiles and the discovery of diamond structurally trapped outside their stability field, have increased the potential of diamondiferous areas. Preservation of diamonds inside the lithosphere requires that the mantleroot remains insulated against excessive reheating and tectonic reworking. Mantle-root friendly and mantle-root destructive structures are distinguished. Small-size cratons are usually the most promising exploration targets. Transport of diamonds to the surface is dependant on' the same criteria of preservation. Only kimberlites and lamproites have been recognized as efficient transport media. Their ascent to the surface is conditioned by a multitude of parameters, amongst them the nature of the magma, the speed of ascent, the presence of pre-existing structures in the crust and the availability of ground water in the near-surface environment. The origin of kimberlite magma probably lies near the transition zone. Mixtures of depleted asthenospheric · sources and metasomatically enriched and possibly subducted materials are likely to be at the origin of the different kimberlite magmas. Kimberlite magmatism correlates generally in time with global tectonic events, triggered by either plume activity or by subduction processes, depending of the tectonic school of thought. Kimberlite alignments have been interpreted as hotspot tracks, and kimberlite magmas as volatile-rich melts issued from the remaining plume tail. The plume head produces flood-basalts in an adjacent "thinspot" of the lithosphere, generally on the edges of the cratons. Kimberlite and lamproite ascent to the surface are unconditionally influenced by regional structures. Rift structures, ring structures, transform faults, suture zones and deep-seated faults have been mentioned as controlling or accompanying features of kimberlite magmatism. Nearsurface emplacement constraints are better understood and the ultimate shape of the intrusion(s) depends on the nature of the country rocks, the availability of ground water and the near-surface faulting pattern. The recent discovery of "fissure" kimberlites is one of the more important breakthroughs of the last decade. With a better understanding of the processes involved in diamond formation, preservation and of kimberlite emplacement, major diamond discoveries have recently increased on all the continents. Successful diamond exploration requires today an integration of all geophysical, petrologic, geochemical and structural information available. The particular study of the northwestern Australian lamproite and kimberlite fields, the Brazilian kimberlites, the easternNorth American kimberlite fields, the Lac de Gras kimberlite field, the South African rich kimberlite provinces, and the Yakutian kimberlite fields provide concrete examples of the geotectonic controls on primary diamond deposits. Area selection criteria based on the previous models and examples, are expected to yield to many more discoveries in the coming years. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Hannon, Camille
- Date: 2013-05-23
- Subjects: Diamonds , Geology, Structural , Diamond deposits , Kimberlite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5047 , http://hdl.handle.net/10962/d1007810 , Diamonds , Geology, Structural , Diamond deposits , Kimberlite
- Description: The origin of diamonds, their preservation and transport to the surface have been important issues over the last decades after the acknowledgement that diamonds are xenocrysts in the host kimberlites and after the discovery of new transport media such as lamproites. Different types of diamonds -E-type diamonds, P-type diamonds- and different types of hosts - Eclogites, Peridotites- have been distinguished. Each type corresponds to particular formation criteria. Ecogitic Diamonds are mostly related to subduction processes, whereas more uncertainties remain regarding the formation of Peridotitic Diamonds. Komatiite extraction and subduction of graphite-bearing serpentinites have been proposed as the more likely processes involved in their formation. A typical mantle signature for diamonds implies a thick, cool, reduced lithosphere. The keel-shape model is the most popular. Archaean cratons are therefore the most promising exploration target and area selection will expect to follow the Clifford's Rule. However, the evidence of cratonic areas hidden under younger formations · through seismic profiles and the discovery of diamond structurally trapped outside their stability field, have increased the potential of diamondiferous areas. Preservation of diamonds inside the lithosphere requires that the mantleroot remains insulated against excessive reheating and tectonic reworking. Mantle-root friendly and mantle-root destructive structures are distinguished. Small-size cratons are usually the most promising exploration targets. Transport of diamonds to the surface is dependant on' the same criteria of preservation. Only kimberlites and lamproites have been recognized as efficient transport media. Their ascent to the surface is conditioned by a multitude of parameters, amongst them the nature of the magma, the speed of ascent, the presence of pre-existing structures in the crust and the availability of ground water in the near-surface environment. The origin of kimberlite magma probably lies near the transition zone. Mixtures of depleted asthenospheric · sources and metasomatically enriched and possibly subducted materials are likely to be at the origin of the different kimberlite magmas. Kimberlite magmatism correlates generally in time with global tectonic events, triggered by either plume activity or by subduction processes, depending of the tectonic school of thought. Kimberlite alignments have been interpreted as hotspot tracks, and kimberlite magmas as volatile-rich melts issued from the remaining plume tail. The plume head produces flood-basalts in an adjacent "thinspot" of the lithosphere, generally on the edges of the cratons. Kimberlite and lamproite ascent to the surface are unconditionally influenced by regional structures. Rift structures, ring structures, transform faults, suture zones and deep-seated faults have been mentioned as controlling or accompanying features of kimberlite magmatism. Nearsurface emplacement constraints are better understood and the ultimate shape of the intrusion(s) depends on the nature of the country rocks, the availability of ground water and the near-surface faulting pattern. The recent discovery of "fissure" kimberlites is one of the more important breakthroughs of the last decade. With a better understanding of the processes involved in diamond formation, preservation and of kimberlite emplacement, major diamond discoveries have recently increased on all the continents. Successful diamond exploration requires today an integration of all geophysical, petrologic, geochemical and structural information available. The particular study of the northwestern Australian lamproite and kimberlite fields, the Brazilian kimberlites, the easternNorth American kimberlite fields, the Lac de Gras kimberlite field, the South African rich kimberlite provinces, and the Yakutian kimberlite fields provide concrete examples of the geotectonic controls on primary diamond deposits. Area selection criteria based on the previous models and examples, are expected to yield to many more discoveries in the coming years. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
Biogeography and community structure of fishes in South African estuaries
- Authors: Harrison, Trevor D
- Date: 2003
- Subjects: Estuarine ecology -- South Africa Estuarine fishes -- South Africa Fish communities -- South Africa Biogeography -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5235 , http://hdl.handle.net/10962/d1005078
- Description: The biogeography and community structure of the fishes of South African estuaries was investigated. In all, 109 systems were examined representing two broad types: temporarily closed and permanently open estuaries. Multivariate analyses of the fish communities identified three biogeographic regions. A cool-temperate region extended along the west and southwest coasts; a warmtemperate zone stretched along the south, southeast and east coasts and a subtropical region occurred along the east coast. The boundaries of these biogeographic regions were also delineated. The general physico-chemical characteristics of the estuaries within the three biogeographic regions also reflected regional differences in climate, rainfall and ocean conditions. Estuarine temperatures followed the trend for marine coastal waters, decreasing from subtropical estuaries toward cool-temperate systems. The low rainfall and runoff in the warm-temperate region together with high evaporation rates and strong seawater input resulted in higher salinities in these estuaries. These factors also accounted for the predominantly clearer waters in warm-temperate estuaries. The estuaries in the three biogeographic regions were also shown to contain somewhat distinctive fish assemblages. Temperature and salinity appeared to be the two main factors affecting the distribution and abundance of fishes in South African estuaries. Subtropical systems were characterised by fishes mostly of tropical origin as well as certain south coast endemic species. Warm-temperate estuaries were dominated by endemic taxa with some tropical species also present. The fish fauna of cooltemperate estuaries mostly comprised south coast endemic species with cosmopolitan and temperate taxa also present. Certain functional components of the ichthyofauna also exhibited slight differences between regions. Freshwater fishes were a major component of closed subtropical estuaries while estuarine resident species were more abundant in warm-temperate estuaries. Overall, estuarine-dependent marine species dominated the fish fauna of the estuaries in all biogeographic regions, signifying that South African estuaries perform a vital nursery function for this group of fishes. Slight differences were also apparent in the trophic structure of the fishes; these were related to environmental differences between regions. Zooplanktivores and fishes that feed on aquatic macrophytes/invertebrates assumed a relatively higher importance in warm-temperate systems. Overall, detritivores dominated the estuarine fish fauna in all regions, indicating that detritus forms the main energy source in South African estuaries.
- Full Text:
- Date Issued: 2003
- Authors: Harrison, Trevor D
- Date: 2003
- Subjects: Estuarine ecology -- South Africa Estuarine fishes -- South Africa Fish communities -- South Africa Biogeography -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5235 , http://hdl.handle.net/10962/d1005078
- Description: The biogeography and community structure of the fishes of South African estuaries was investigated. In all, 109 systems were examined representing two broad types: temporarily closed and permanently open estuaries. Multivariate analyses of the fish communities identified three biogeographic regions. A cool-temperate region extended along the west and southwest coasts; a warmtemperate zone stretched along the south, southeast and east coasts and a subtropical region occurred along the east coast. The boundaries of these biogeographic regions were also delineated. The general physico-chemical characteristics of the estuaries within the three biogeographic regions also reflected regional differences in climate, rainfall and ocean conditions. Estuarine temperatures followed the trend for marine coastal waters, decreasing from subtropical estuaries toward cool-temperate systems. The low rainfall and runoff in the warm-temperate region together with high evaporation rates and strong seawater input resulted in higher salinities in these estuaries. These factors also accounted for the predominantly clearer waters in warm-temperate estuaries. The estuaries in the three biogeographic regions were also shown to contain somewhat distinctive fish assemblages. Temperature and salinity appeared to be the two main factors affecting the distribution and abundance of fishes in South African estuaries. Subtropical systems were characterised by fishes mostly of tropical origin as well as certain south coast endemic species. Warm-temperate estuaries were dominated by endemic taxa with some tropical species also present. The fish fauna of cooltemperate estuaries mostly comprised south coast endemic species with cosmopolitan and temperate taxa also present. Certain functional components of the ichthyofauna also exhibited slight differences between regions. Freshwater fishes were a major component of closed subtropical estuaries while estuarine resident species were more abundant in warm-temperate estuaries. Overall, estuarine-dependent marine species dominated the fish fauna of the estuaries in all biogeographic regions, signifying that South African estuaries perform a vital nursery function for this group of fishes. Slight differences were also apparent in the trophic structure of the fishes; these were related to environmental differences between regions. Zooplanktivores and fishes that feed on aquatic macrophytes/invertebrates assumed a relatively higher importance in warm-temperate systems. Overall, detritivores dominated the estuarine fish fauna in all regions, indicating that detritus forms the main energy source in South African estuaries.
- Full Text:
- Date Issued: 2003
Molecular identification of some forensically important blowflies of southern Africa and Australia
- Harvey, M L, Mansell, M W, Villet, Martin H, Dadour, I R
- Authors: Harvey, M L , Mansell, M W , Villet, Martin H , Dadour, I R
- Date: 2003
- Language: English
- Type: text , Article
- Identifier: vital:6953 , http://hdl.handle.net/10962/d1011986
- Description: One major aspect of research in forensic entomology is the investigation of molecular techniques for the accurate identification of insects. Studies to date have addressed the corpse fauna of many geographical regions, but generally neglected the southern African calliphorid species. In this study, forensically significant calliphorids from South Africa, Swaziland, Botswana and Zimbabwe and Australia were sequenced over an 1167 base pair region of the COI gene. Phylogenetic analysis was performed to examine the ability of the region to resolve species identities and taxonomic relationships between species. Analyses by neighbour-joining, maximum parsimony and maximum likelihood methods all showed the potential of this region to provide the necessary species-level identifications for application to post-mortem interval (PMI) estimation; however, higher level taxonomic relationships did vary according to method of analysis. Intraspecific variation was also considered in relation to determining suitable maximum levels of variation to be expected during analysis. Individuals of some species in the study represented populations from both South Africa and the east coast of Australia, yet maximum intraspecific variation over this gene region was calculated at 0.8%, with minimum interspecific variation at 3%, indicating distinct ranges of variation to be expected at intra- and interspecific levels. This region therefore appears to provide southern African forensic entomologists with a new technique for providing accurate identification for application to estimation of PMI.
- Full Text:
- Date Issued: 2003
- Authors: Harvey, M L , Mansell, M W , Villet, Martin H , Dadour, I R
- Date: 2003
- Language: English
- Type: text , Article
- Identifier: vital:6953 , http://hdl.handle.net/10962/d1011986
- Description: One major aspect of research in forensic entomology is the investigation of molecular techniques for the accurate identification of insects. Studies to date have addressed the corpse fauna of many geographical regions, but generally neglected the southern African calliphorid species. In this study, forensically significant calliphorids from South Africa, Swaziland, Botswana and Zimbabwe and Australia were sequenced over an 1167 base pair region of the COI gene. Phylogenetic analysis was performed to examine the ability of the region to resolve species identities and taxonomic relationships between species. Analyses by neighbour-joining, maximum parsimony and maximum likelihood methods all showed the potential of this region to provide the necessary species-level identifications for application to post-mortem interval (PMI) estimation; however, higher level taxonomic relationships did vary according to method of analysis. Intraspecific variation was also considered in relation to determining suitable maximum levels of variation to be expected during analysis. Individuals of some species in the study represented populations from both South Africa and the east coast of Australia, yet maximum intraspecific variation over this gene region was calculated at 0.8%, with minimum interspecific variation at 3%, indicating distinct ranges of variation to be expected at intra- and interspecific levels. This region therefore appears to provide southern African forensic entomologists with a new technique for providing accurate identification for application to estimation of PMI.
- Full Text:
- Date Issued: 2003
An integrated economic developmental appraisal of the South African mariculture industry
- Authors: Hepburn, Bruce
- Date: 2003
- Subjects: Mariculture -- South Africa -- Economic aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:941 , http://hdl.handle.net/10962/d1002674 , Mariculture -- South Africa -- Economic aspects
- Description: Current coastal legislative and institutional reformulation has effectively established new principles for the promotion of sustainable, co-ordinated integrated coastal development to be achieved through facilitatory, co-operative management mechanisms. In accordance, collaborative expansion and diversification of mariculture has been identified as a strategic mechanism for realising sustainable coastal development. Present limited foundational understanding regarding the emergent commercial contingent’s economic-institutional structure has constrained the effectiveness of current centralised broad objective formulation based planning techniques. By drawing upon findings of the 2001 National Mariculture Baseline survey, key economic development and institutional components requiring dedicated attention for further realising industry’s inherent growth potential to supply domestic and growing global aquaculture markets are examined in an inductive explorative framework. Attention is also directed towards promoting realisation of collaborative mariculture development initiatives to redress dualistic development disparities in previously marginalised coastal localities. Finally, synthesis between traditional bureaucratic centralised co-ordinated planning and regionalised decentralised implementation orientated capacity building frameworks displaying a greater relevant stakeholder participatory ethos are examined.
- Full Text:
- Date Issued: 2003
- Authors: Hepburn, Bruce
- Date: 2003
- Subjects: Mariculture -- South Africa -- Economic aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:941 , http://hdl.handle.net/10962/d1002674 , Mariculture -- South Africa -- Economic aspects
- Description: Current coastal legislative and institutional reformulation has effectively established new principles for the promotion of sustainable, co-ordinated integrated coastal development to be achieved through facilitatory, co-operative management mechanisms. In accordance, collaborative expansion and diversification of mariculture has been identified as a strategic mechanism for realising sustainable coastal development. Present limited foundational understanding regarding the emergent commercial contingent’s economic-institutional structure has constrained the effectiveness of current centralised broad objective formulation based planning techniques. By drawing upon findings of the 2001 National Mariculture Baseline survey, key economic development and institutional components requiring dedicated attention for further realising industry’s inherent growth potential to supply domestic and growing global aquaculture markets are examined in an inductive explorative framework. Attention is also directed towards promoting realisation of collaborative mariculture development initiatives to redress dualistic development disparities in previously marginalised coastal localities. Finally, synthesis between traditional bureaucratic centralised co-ordinated planning and regionalised decentralised implementation orientated capacity building frameworks displaying a greater relevant stakeholder participatory ethos are examined.
- Full Text:
- Date Issued: 2003
Looking underneath: deconstruction in Hogarth's Industry and Idleness
- Authors: Herbst, Michael
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147803 , vital:38674 , https://doi.org/10.1080/00043389.2003.11877010
- Description: In Hogarth's engraved series Industry and Idleness two young men from lower-class backgrounds are apprenticed to Mr West, a weaver. The first plate (1) lays bare the two apprentices' marked difference in temperament: Francis Goodchild works contentedly at his well-lit loom with his 'Prentice's Guide- a standard manual of instruction and advice for London apprentices in various trades - open on the floor below him. In the gloomy foreground Thomas Idle snores crassly at his loom, oblivious of his 'Prentice's Guide, which has apparently been reduced to tatters by the cat that now toys with the abandoned shuttle.
- Full Text:
- Date Issued: 2017
- Authors: Herbst, Michael
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147803 , vital:38674 , https://doi.org/10.1080/00043389.2003.11877010
- Description: In Hogarth's engraved series Industry and Idleness two young men from lower-class backgrounds are apprenticed to Mr West, a weaver. The first plate (1) lays bare the two apprentices' marked difference in temperament: Francis Goodchild works contentedly at his well-lit loom with his 'Prentice's Guide- a standard manual of instruction and advice for London apprentices in various trades - open on the floor below him. In the gloomy foreground Thomas Idle snores crassly at his loom, oblivious of his 'Prentice's Guide, which has apparently been reduced to tatters by the cat that now toys with the abandoned shuttle.
- Full Text:
- Date Issued: 2017
Cyber crime affecting some businesses in South Africa
- Authors: Herselman, Martha Elizabeth
- Date: 2003
- Subjects: Computer crimes , Business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MTech (Business Information Systems)
- Identifier: vital:10793 , http://hdl.handle.net/10948/212 , Computer crimes , Business enterprises -- South Africa
- Description: This study shows that cyber crime is a recent addition to the list of crimes that can adversely affect businesses directly of indirectly. This phenomenon was not directly prosecutable in South Africa until the enactment of the ECT Act in July 2002. However this Act also prevents businesses to fully prosecute a hacker due to incompleteness. Any kind of commercially related crime can be duplicated as cyber crime. Therefore very little research appears or has been documented about cyber crime in South African companies before 2003.11.21 The motivation to do this study was that businesses often loose millions in cyber attacks, not necessarily through direct theft but by the loss of service and damage to the image of the company. Most of the companies that were approached for interviews on cyber crime were reluctant to share the fact that they were hacked or that cyber crime occurred at their company as it violates their security policies and may expose their fragile security platforms. The purpose of this study was to attempt to get an overall view on how South African businesses are affected by cyber crime in the banking and short term insurance sector of the South African industry and also to determine what legislation exist in this country to protect them. The case study approach was used to determine the affect of cyber crime on businesses like banks and insurance companies. Each case was interviewed, monitored and was observed over a period of a year. This study discloses the evaluation of the results of how cyber crime affected the cases, which were part of this study. The banks felt that they were at an increased risk both externally and internally, which is likely to increase as the migration towards electronic commerce occurs. The insurance industry felt that they are not yet affected by external cyber crime attacks in this country.
- Full Text:
- Date Issued: 2003
- Authors: Herselman, Martha Elizabeth
- Date: 2003
- Subjects: Computer crimes , Business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MTech (Business Information Systems)
- Identifier: vital:10793 , http://hdl.handle.net/10948/212 , Computer crimes , Business enterprises -- South Africa
- Description: This study shows that cyber crime is a recent addition to the list of crimes that can adversely affect businesses directly of indirectly. This phenomenon was not directly prosecutable in South Africa until the enactment of the ECT Act in July 2002. However this Act also prevents businesses to fully prosecute a hacker due to incompleteness. Any kind of commercially related crime can be duplicated as cyber crime. Therefore very little research appears or has been documented about cyber crime in South African companies before 2003.11.21 The motivation to do this study was that businesses often loose millions in cyber attacks, not necessarily through direct theft but by the loss of service and damage to the image of the company. Most of the companies that were approached for interviews on cyber crime were reluctant to share the fact that they were hacked or that cyber crime occurred at their company as it violates their security policies and may expose their fragile security platforms. The purpose of this study was to attempt to get an overall view on how South African businesses are affected by cyber crime in the banking and short term insurance sector of the South African industry and also to determine what legislation exist in this country to protect them. The case study approach was used to determine the affect of cyber crime on businesses like banks and insurance companies. Each case was interviewed, monitored and was observed over a period of a year. This study discloses the evaluation of the results of how cyber crime affected the cases, which were part of this study. The banks felt that they were at an increased risk both externally and internally, which is likely to increase as the migration towards electronic commerce occurs. The insurance industry felt that they are not yet affected by external cyber crime attacks in this country.
- Full Text:
- Date Issued: 2003
The development of an instrument to measure intrapreneurship: entrepreneurship within the corporate setting
- Authors: Hill, Marguerite Elizabeth
- Date: 2003
- Subjects: Entrepreneurship , Psychology, Industrial , Organizational change
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2991 , http://hdl.handle.net/10962/d1002500 , Entrepreneurship , Psychology, Industrial , Organizational change
- Description: “Intrapreneurship is not a choice, it is the only survival attitude” (Pinchot, 2000, p.75). In 1985 Pinchot coined the term ‘intrapreneurship’, short for intra-corporate entrepreneurship, which describes the practice of entrepreneurship within organisations. Intrapreneurship is increasingly becoming a term used in the business world to describe organisations that are willing to pursue opportunities, initiate actions, and emphasise new, innovative products or services. Due to the dynamic nature of modern organisations, it is imperative that organisations and their managers remain receptive to new ideas, approaches and attitudes. It is therefore the belief that rapid and cost-effective innovation is the primary source of lasting competitive advantage in the twenty-first century, leaving organisations no alternative but to become intrapreneurial or cease to exist. This thesis focuses on this need and examines ways in which intrapreneurship can be measured in organisations in order to provide a benchmark for further organisational development. A questionnaire (known as the Intrapreneurial Intensity Index) was designed and distributed to a sample of 500 employees working in large South African organisations, which classified themselves as ‘forward-thinking’ and aimed for an intrapreneurial ‘type of thinking’. The results obtained from these questionnaires underwent item analysis, after which the questionnaire was redesigned in an electronic format. A pilot case study was then conducted in order to test the reliability of the instrument. Finally the questionnaire was redistributed to a sample of six organisations that are viewed as being ‘intrapreneurial’ and two that are regarded as being ‘non-intrapreneurial’. The data from this sample was used to test the validity of the Intrapreneurial Intensity Index and to demonstrate its application. This study resulted in an instrument that can be used to ascertain the intensity of intrapreneurship present in a large organisation. Specifically, this instrument can provide an overall view of the organisation’s intrapreneurial ability, as well as identify the specific areas in the organisation that require change or modification in order to become more intrapreneurial. This instrument provides a valuable means of identifying areas in need of organisational change, by determining an organisation’s intrapreneurial properties in the organisation’s core areas.
- Full Text:
- Date Issued: 2003
- Authors: Hill, Marguerite Elizabeth
- Date: 2003
- Subjects: Entrepreneurship , Psychology, Industrial , Organizational change
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2991 , http://hdl.handle.net/10962/d1002500 , Entrepreneurship , Psychology, Industrial , Organizational change
- Description: “Intrapreneurship is not a choice, it is the only survival attitude” (Pinchot, 2000, p.75). In 1985 Pinchot coined the term ‘intrapreneurship’, short for intra-corporate entrepreneurship, which describes the practice of entrepreneurship within organisations. Intrapreneurship is increasingly becoming a term used in the business world to describe organisations that are willing to pursue opportunities, initiate actions, and emphasise new, innovative products or services. Due to the dynamic nature of modern organisations, it is imperative that organisations and their managers remain receptive to new ideas, approaches and attitudes. It is therefore the belief that rapid and cost-effective innovation is the primary source of lasting competitive advantage in the twenty-first century, leaving organisations no alternative but to become intrapreneurial or cease to exist. This thesis focuses on this need and examines ways in which intrapreneurship can be measured in organisations in order to provide a benchmark for further organisational development. A questionnaire (known as the Intrapreneurial Intensity Index) was designed and distributed to a sample of 500 employees working in large South African organisations, which classified themselves as ‘forward-thinking’ and aimed for an intrapreneurial ‘type of thinking’. The results obtained from these questionnaires underwent item analysis, after which the questionnaire was redesigned in an electronic format. A pilot case study was then conducted in order to test the reliability of the instrument. Finally the questionnaire was redistributed to a sample of six organisations that are viewed as being ‘intrapreneurial’ and two that are regarded as being ‘non-intrapreneurial’. The data from this sample was used to test the validity of the Intrapreneurial Intensity Index and to demonstrate its application. This study resulted in an instrument that can be used to ascertain the intensity of intrapreneurship present in a large organisation. Specifically, this instrument can provide an overall view of the organisation’s intrapreneurial ability, as well as identify the specific areas in the organisation that require change or modification in order to become more intrapreneurial. This instrument provides a valuable means of identifying areas in need of organisational change, by determining an organisation’s intrapreneurial properties in the organisation’s core areas.
- Full Text:
- Date Issued: 2003
South African research in the hydrological sciences: 1999-2002
- Hughes, Denis A, Ashton, P, Gorgons, A, Jewitt, G P W, Schulze, R, Smithers, J, Pegram, G, Dube, R
- Authors: Hughes, Denis A , Ashton, P , Gorgons, A , Jewitt, G P W , Schulze, R , Smithers, J , Pegram, G , Dube, R
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:7074 , http://hdl.handle.net/10962/d1009531
- Description: The principal activities of South African researchers in hydrology and water resources during the reporting period have been concerned with ground- and surface-water interactions, rainfall-runoff modelling, the establishment of improved regional water resource databases, the management of transboundary water resource systems, the ecological reserve, and quantifying the impacts of streamflow reduction activities. Most of these studies have focused on supporting the radically new provisions of the National Water Act of 1998.
- Full Text:
- Date Issued: 2003
- Authors: Hughes, Denis A , Ashton, P , Gorgons, A , Jewitt, G P W , Schulze, R , Smithers, J , Pegram, G , Dube, R
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:7074 , http://hdl.handle.net/10962/d1009531
- Description: The principal activities of South African researchers in hydrology and water resources during the reporting period have been concerned with ground- and surface-water interactions, rainfall-runoff modelling, the establishment of improved regional water resource databases, the management of transboundary water resource systems, the ecological reserve, and quantifying the impacts of streamflow reduction activities. Most of these studies have focused on supporting the radically new provisions of the National Water Act of 1998.
- Full Text:
- Date Issued: 2003
The importance of managing cultural change in the succession process within family businesses in the Gauteng area
- Authors: Hynd, Dale Vaughan
- Date: 2003
- Subjects: Family-owned business enterprises -- South Africa Family-owned business enterprises -- Succession Corporate culture -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3173 , http://hdl.handle.net/10962/d1007802
- Description: 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.
- Full Text:
- Date Issued: 2003
- Authors: Hynd, Dale Vaughan
- Date: 2003
- Subjects: Family-owned business enterprises -- South Africa Family-owned business enterprises -- Succession Corporate culture -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3173 , http://hdl.handle.net/10962/d1007802
- Description: 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.
- Full Text:
- Date Issued: 2003
Binding and transcriptional activation by Uga3p, a zinc binuclear cluster protein of Saccharomyces cerevisiae redefining the UAS [subscript GABA] and the Uga3p binding site
- Authors: Idicula, Anu Mary
- Date: 2003
- Subjects: Saccharomyces cerevisiae GABA
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3933 , http://hdl.handle.net/10962/d1003992
- Description: Uga3p, a member of the zinc binuclear cluster transcription factor family, is required for [gamma]-aminobutyric acid-dependent transcription of the UGA genes in Saccharomyces cerevisiae. Crystallographic data of some of the protein-DNA complexes of this family reveal that members of this family bind to CGG triplets. A conserved 19-nucleotide activation element in certain UGA gene promoter regions contains a CCG-N4-CGG everted repeat, proposed to be the binding site of Uga3p, UAS[subscript GABA]. The spacer region (N4) between the CGG triplets has been suggested to be the specificity determinant for binding to UAS[subscript GABA]. The data available from the Saccharomyces genome database indicates that there are multiple repeats of -CCG-N4-CGG- regions within the genome. These transcription factors are involved in the activation of specific pathways and the question arises as to how their specificity of binding is determined. The aim of this study was to understand the binding characteristics of Uga3p to UAS[subscript GABA] and to determine the affinity and specificity of this interaction. In this study, full-length (tagged and untagged) and truncated (1-124 a.a.) Uga3p was produced in a heterologous expression system (E. coli). The interaction of Uga3p with UAS[subscript GABA] in Saccharomyces cerevisiae was characterized in terms of binding in vitro and the transcriptional activation of lacZ reporter genes in vivo. The Uga3p was capable of binding to these sites in vitro independent of exogenous GABA. Electrophoretic mobility shift assays (EMSA) of the full-length Uga3p with the wild type UAS[subscript GABA] sequences produced two distinct mobility complexes. The complexes formed in the EMSA of the full-length Uga3p were those specific to the interaction of the Uga3p to UAS[subscript GABA]. The truncated Uga3p(1-124 a.a.), which has the DNA-binding zinc cluster domain, the linker region and the putative coiled-coil domain was not functionally equivalent to the full-length protein with respect to binding in vitro because the EMSAs of the UAS[subscript GABA] with the truncated Uga3p produced indistinct complexes. EMSAs using mutant UAS[subscript GABA] sequences and heterologously-produced full-length Uga3p, demonstrated that UAS[subscript GABA] consists of two, independent Uga3p-binding sites. This work presents evidence that the two Uga3p molecules bound to UAS[subscript GABA] most likely interact with each other. Unlike other zinc cluster binding sites the Uga3p-binding site is an asymmetric site of 5’-SGCGGNWWT-3’ (S= G or C, W = A or T and N = no nucleotide or G or C). UAS[subscript GABA] is a palindrome containing the two asymmetric Uga3p-binding sites. The two-site consensus sequence required for the binding of Uga3p to the UAS[subscript GABA] is present upstream of UGA1 (region -387 to -370) and UGA4 (region -403 to -387). Furthermore, a single Uga3p-binding site was identified in the 5’ untranslated regions of UGA2 (region -219 to -211). GABA-dependent transcriptional activation by UAS[subscript GABA] in vivo could be directly correlated to a high affinity, specific interaction of two Uga3p molecules to this UAS. Binding with high affinity required the conserved sequences flanking the everted repeat. This study provided evidence that the binding pattern of Uga3p is novel compared to other zinc cluster motifs investigated, as the sequences flanking the everted repeat are important regions for recognition by Uga3p. The studies with the truncated Uga3p (1 –124 a.a.), also suggested that the regions C-terminal to the DNA-binding motif and putative coiled-coil area of this protein are important for Uga3p-specific interactions with UAS[subscript GABA]. Investigation of regions C-terminal to the zinc cluster, linker and putative coiledcoil revealed an eight-motif regulatory region similar to that in other zinc cluster proteins. This indicated that the regions C-terminal to these domains are important for the regulation and activity of these proteins. A putative seven repeat WD40-like motif was identified within this region. This putative domain has been speculated to be important for protein-protein interactions. Phosphorylation and dephosphorylation in other proteins of this class have been indicated to be important for the regulation of the activity of these proteins. The bioinformatic analysis of Uga3p revealed two possible cAMP/cGMP-dependent protein kinase phosphorylation sites, four putative protein kinase C phosphorylation motifs and four putative casein kinase II phosphorylation motifs. This study has contributed to the understanding of the nature of interactions between Uga3p and its specific UAS [subscript GABA] and how the regions flanking the everted repeat determine its specificity. The comparison of the nature of the binding of truncated and full-length Uga3p in vitro provided evidence for the role played by the full-length protein in determining this specific interaction. This evidence suggested that the in vitro binding evidence for other proteins of this family, using truncated peptides that carry the DNA-binding domain, might not reflect the true nature of interactions between the proteins of this class and their specific UASs in vivo.
- Full Text:
- Date Issued: 2003
- Authors: Idicula, Anu Mary
- Date: 2003
- Subjects: Saccharomyces cerevisiae GABA
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3933 , http://hdl.handle.net/10962/d1003992
- Description: Uga3p, a member of the zinc binuclear cluster transcription factor family, is required for [gamma]-aminobutyric acid-dependent transcription of the UGA genes in Saccharomyces cerevisiae. Crystallographic data of some of the protein-DNA complexes of this family reveal that members of this family bind to CGG triplets. A conserved 19-nucleotide activation element in certain UGA gene promoter regions contains a CCG-N4-CGG everted repeat, proposed to be the binding site of Uga3p, UAS[subscript GABA]. The spacer region (N4) between the CGG triplets has been suggested to be the specificity determinant for binding to UAS[subscript GABA]. The data available from the Saccharomyces genome database indicates that there are multiple repeats of -CCG-N4-CGG- regions within the genome. These transcription factors are involved in the activation of specific pathways and the question arises as to how their specificity of binding is determined. The aim of this study was to understand the binding characteristics of Uga3p to UAS[subscript GABA] and to determine the affinity and specificity of this interaction. In this study, full-length (tagged and untagged) and truncated (1-124 a.a.) Uga3p was produced in a heterologous expression system (E. coli). The interaction of Uga3p with UAS[subscript GABA] in Saccharomyces cerevisiae was characterized in terms of binding in vitro and the transcriptional activation of lacZ reporter genes in vivo. The Uga3p was capable of binding to these sites in vitro independent of exogenous GABA. Electrophoretic mobility shift assays (EMSA) of the full-length Uga3p with the wild type UAS[subscript GABA] sequences produced two distinct mobility complexes. The complexes formed in the EMSA of the full-length Uga3p were those specific to the interaction of the Uga3p to UAS[subscript GABA]. The truncated Uga3p(1-124 a.a.), which has the DNA-binding zinc cluster domain, the linker region and the putative coiled-coil domain was not functionally equivalent to the full-length protein with respect to binding in vitro because the EMSAs of the UAS[subscript GABA] with the truncated Uga3p produced indistinct complexes. EMSAs using mutant UAS[subscript GABA] sequences and heterologously-produced full-length Uga3p, demonstrated that UAS[subscript GABA] consists of two, independent Uga3p-binding sites. This work presents evidence that the two Uga3p molecules bound to UAS[subscript GABA] most likely interact with each other. Unlike other zinc cluster binding sites the Uga3p-binding site is an asymmetric site of 5’-SGCGGNWWT-3’ (S= G or C, W = A or T and N = no nucleotide or G or C). UAS[subscript GABA] is a palindrome containing the two asymmetric Uga3p-binding sites. The two-site consensus sequence required for the binding of Uga3p to the UAS[subscript GABA] is present upstream of UGA1 (region -387 to -370) and UGA4 (region -403 to -387). Furthermore, a single Uga3p-binding site was identified in the 5’ untranslated regions of UGA2 (region -219 to -211). GABA-dependent transcriptional activation by UAS[subscript GABA] in vivo could be directly correlated to a high affinity, specific interaction of two Uga3p molecules to this UAS. Binding with high affinity required the conserved sequences flanking the everted repeat. This study provided evidence that the binding pattern of Uga3p is novel compared to other zinc cluster motifs investigated, as the sequences flanking the everted repeat are important regions for recognition by Uga3p. The studies with the truncated Uga3p (1 –124 a.a.), also suggested that the regions C-terminal to the DNA-binding motif and putative coiled-coil area of this protein are important for Uga3p-specific interactions with UAS[subscript GABA]. Investigation of regions C-terminal to the zinc cluster, linker and putative coiledcoil revealed an eight-motif regulatory region similar to that in other zinc cluster proteins. This indicated that the regions C-terminal to these domains are important for the regulation and activity of these proteins. A putative seven repeat WD40-like motif was identified within this region. This putative domain has been speculated to be important for protein-protein interactions. Phosphorylation and dephosphorylation in other proteins of this class have been indicated to be important for the regulation of the activity of these proteins. The bioinformatic analysis of Uga3p revealed two possible cAMP/cGMP-dependent protein kinase phosphorylation sites, four putative protein kinase C phosphorylation motifs and four putative casein kinase II phosphorylation motifs. This study has contributed to the understanding of the nature of interactions between Uga3p and its specific UAS [subscript GABA] and how the regions flanking the everted repeat determine its specificity. The comparison of the nature of the binding of truncated and full-length Uga3p in vitro provided evidence for the role played by the full-length protein in determining this specific interaction. This evidence suggested that the in vitro binding evidence for other proteins of this family, using truncated peptides that carry the DNA-binding domain, might not reflect the true nature of interactions between the proteins of this class and their specific UASs in vivo.
- Full Text:
- Date Issued: 2003
The impact of US Peace Corps volunteers on the management and leadership of a school in Namibia: a case study
- Authors: Ipangelwa, Anna
- Date: 2003
- Subjects: Peace Corps (U.S.) Volunteer workers in Education -- Namibia Education -- Namibia Education and state -- Namibia Educational change -- Namibia School management and organization -- Namibia Educational leadership -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1561 , http://hdl.handle.net/10962/d1003443
- Description: Peace Corps Volunteer teachers have played a significant role in Namibia’s attempts to restructure education in line with its policy of education for all. While we have learned a great deal in recent years about how Peace Corps Volunteer Teachers have achieved their stated goals and objectives of teaching students and training serving teachers, we still know relatively little about the role they may have played in school management. The purpose of this study is to examine the impact of Peace Corps volunteers work on the management and leadership of the schools they serve. The study focuses on the work of two volunteers based in a combined school in the Ondangwa West educational region of Namibia. The study adopts a qualitative approach and seeks to establish whether there has been an impact by Peace Corps volunteer’s work on the management and leadership of this school by focusing on (a) activities performed by Peace Corps volunteers; (b) the experiences of both management and staff in working with Peace Corps volunteers; (c) whether the presence of Peace Corps volunteers that served at the school influence the management and leadership of the school; (d) how the duties and activities performed by these volunteers were perceived by the students, teachers and community. The interview questions that were used to collect data from seven respondents were based on the literature from Peace Corps and the Ministry of Basic Education, Culture and Sport as well as education management and leadership literature. The findings indicate that volunteers that served at this school performed management and leadership related activities with the students, teachers and community and that these activities are having an effect on the management and leadership of the school.
- Full Text:
- Date Issued: 2003
- Authors: Ipangelwa, Anna
- Date: 2003
- Subjects: Peace Corps (U.S.) Volunteer workers in Education -- Namibia Education -- Namibia Education and state -- Namibia Educational change -- Namibia School management and organization -- Namibia Educational leadership -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1561 , http://hdl.handle.net/10962/d1003443
- Description: Peace Corps Volunteer teachers have played a significant role in Namibia’s attempts to restructure education in line with its policy of education for all. While we have learned a great deal in recent years about how Peace Corps Volunteer Teachers have achieved their stated goals and objectives of teaching students and training serving teachers, we still know relatively little about the role they may have played in school management. The purpose of this study is to examine the impact of Peace Corps volunteers work on the management and leadership of the schools they serve. The study focuses on the work of two volunteers based in a combined school in the Ondangwa West educational region of Namibia. The study adopts a qualitative approach and seeks to establish whether there has been an impact by Peace Corps volunteer’s work on the management and leadership of this school by focusing on (a) activities performed by Peace Corps volunteers; (b) the experiences of both management and staff in working with Peace Corps volunteers; (c) whether the presence of Peace Corps volunteers that served at the school influence the management and leadership of the school; (d) how the duties and activities performed by these volunteers were perceived by the students, teachers and community. The interview questions that were used to collect data from seven respondents were based on the literature from Peace Corps and the Ministry of Basic Education, Culture and Sport as well as education management and leadership literature. The findings indicate that volunteers that served at this school performed management and leadership related activities with the students, teachers and community and that these activities are having an effect on the management and leadership of the school.
- Full Text:
- Date Issued: 2003
Studies of the environmental and endocrine control of reproduction in the four striped field mouse, Rhabdomys pumilio
- Authors: Jackson, Claire
- Date: 2003
- Subjects: Microtus Microtus -- South Africa -- Reproduction Mice -- Reproduction
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5777 , http://hdl.handle.net/10962/d1005465
- Description: Previous studies of the control of reproduction in Rhabdomys pumilio have shown that day length alone does not inhibit spermatogenesis, that a reduction in food availability and ambient temperature results in an inhibition of gametogenesis, that females are more susceptible to inhibition than are males, and that mice that are able to maintain a body fat store in the face of an energetic challenge, are less likely to show reproductive inhibition than those that lose their fat store. In the present study, field and laboratory experiments were conducted to examine the effects of winter food supplementation on reproduction and population dynamics, and the effects of exogenous GnRH, leptin and mercaptoacetate (MA) on reproductive activity of Rhabdomys pumilio exposed to an energetic challenge. In the field food supplementation experiments in Thomas Baines Nature Reserve (2000, 2001), there was no winter inhibition of reproduction and provision of supplementary food had little effect. While at Mountain Zebra National Park (2002) winter was harsher, females became reproductively inactive, spermatogenesis continued and the provision of extra food resulted in higher rates of individual growth and larger reproductive organs. Treatment of mice that had been exposed to a prolonged energetic challenge, with exogenous GnRH (1µg/mouse/treatment) resulted in an increase in the masses of the testes and epididymides, and in the activity of the reproductive organs. Treatment with exogenous leptin (40µg/mouse/treatment), concurrently with an energetic challenge, countered the negative effects of the energetic challenge, and treated males had larger reproductive organs. MA (600µmol/kg body mass), given concurrently with an energetic challenge, did not inhibit fat metabolism, although the high-fat diet countered the effects of the energetic challenge. Results suggest that the first response of male Rhabdomys pumilio to an energetic challenge is a reduction in the size of the reproductive organs, without an inhibition of spermatogenesis. It is likely that this effect is mediated via white fat and leptin, and leptin’s influence on the hypothalamic-pituitary-gonad axis. Results of the study support the suggestion that females are more sensitive to reproductive inhibition than males and that reproduction in Rhabdomys pumilio is truly opportunistic.
- Full Text:
- Date Issued: 2003
- Authors: Jackson, Claire
- Date: 2003
- Subjects: Microtus Microtus -- South Africa -- Reproduction Mice -- Reproduction
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5777 , http://hdl.handle.net/10962/d1005465
- Description: Previous studies of the control of reproduction in Rhabdomys pumilio have shown that day length alone does not inhibit spermatogenesis, that a reduction in food availability and ambient temperature results in an inhibition of gametogenesis, that females are more susceptible to inhibition than are males, and that mice that are able to maintain a body fat store in the face of an energetic challenge, are less likely to show reproductive inhibition than those that lose their fat store. In the present study, field and laboratory experiments were conducted to examine the effects of winter food supplementation on reproduction and population dynamics, and the effects of exogenous GnRH, leptin and mercaptoacetate (MA) on reproductive activity of Rhabdomys pumilio exposed to an energetic challenge. In the field food supplementation experiments in Thomas Baines Nature Reserve (2000, 2001), there was no winter inhibition of reproduction and provision of supplementary food had little effect. While at Mountain Zebra National Park (2002) winter was harsher, females became reproductively inactive, spermatogenesis continued and the provision of extra food resulted in higher rates of individual growth and larger reproductive organs. Treatment of mice that had been exposed to a prolonged energetic challenge, with exogenous GnRH (1µg/mouse/treatment) resulted in an increase in the masses of the testes and epididymides, and in the activity of the reproductive organs. Treatment with exogenous leptin (40µg/mouse/treatment), concurrently with an energetic challenge, countered the negative effects of the energetic challenge, and treated males had larger reproductive organs. MA (600µmol/kg body mass), given concurrently with an energetic challenge, did not inhibit fat metabolism, although the high-fat diet countered the effects of the energetic challenge. Results suggest that the first response of male Rhabdomys pumilio to an energetic challenge is a reduction in the size of the reproductive organs, without an inhibition of spermatogenesis. It is likely that this effect is mediated via white fat and leptin, and leptin’s influence on the hypothalamic-pituitary-gonad axis. Results of the study support the suggestion that females are more sensitive to reproductive inhibition than males and that reproduction in Rhabdomys pumilio is truly opportunistic.
- Full Text:
- Date Issued: 2003
An investigation into whether a leadership and management development project changed the perceptions of the educators in a black, disadvantaged school
- Authors: Jaftha, A P
- Date: 2003
- Subjects: University of Port Elizabeth -- Institute for Development Planning and Research Delta Foundation -- Centres of Learning School management and organization -- South Africa Educational leadership -- South Africa Educational change -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1620 , http://hdl.handle.net/10962/d1003502
- Description: This study investigates whether a leadership and management development programme changed the management perceptions of the teachers of one of the schools that participated in the programme. The programme seeks to change the organisational culture of schools and develop effective management. The development philosophy of the programme is informed by literature on school effectiveness, organisation development, whole school development and systemic change. My research is conducted in the interpretive paradigm. Interpretive researchers view reality a construct of the human mind, and therefore the way people perceive the world is not necessarily the same since there can be different understandings of what is real. I employ convenience sampling to select the school and purposive sampling to identify my research participants. Whilst overall impression that the data conveys is that much of the programme does not seem to have had a lasting effect on the culture of the school, it nonetheless made an impression on the teachers’ perceptions of management. There clearly seems to be a greater appreciation of participative management processes. The reintroduction of proper prior planning played a decisive role in re-establishing sound work ethics at the school and contributes to a more structured approach to events at the school. Some sort of organisational learning has also been introduced at the school. The realisation on the part of the staff that they now have their destiny in their own hands is an especially critical development. And whilst the vision is not a compelling force in the organisation, it has nevertheless produced some strategic focus at the school. The insights and skills they acquired concerning resource management will also stand them in good stead.
- Full Text:
- Date Issued: 2003
- Authors: Jaftha, A P
- Date: 2003
- Subjects: University of Port Elizabeth -- Institute for Development Planning and Research Delta Foundation -- Centres of Learning School management and organization -- South Africa Educational leadership -- South Africa Educational change -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1620 , http://hdl.handle.net/10962/d1003502
- Description: This study investigates whether a leadership and management development programme changed the management perceptions of the teachers of one of the schools that participated in the programme. The programme seeks to change the organisational culture of schools and develop effective management. The development philosophy of the programme is informed by literature on school effectiveness, organisation development, whole school development and systemic change. My research is conducted in the interpretive paradigm. Interpretive researchers view reality a construct of the human mind, and therefore the way people perceive the world is not necessarily the same since there can be different understandings of what is real. I employ convenience sampling to select the school and purposive sampling to identify my research participants. Whilst overall impression that the data conveys is that much of the programme does not seem to have had a lasting effect on the culture of the school, it nonetheless made an impression on the teachers’ perceptions of management. There clearly seems to be a greater appreciation of participative management processes. The reintroduction of proper prior planning played a decisive role in re-establishing sound work ethics at the school and contributes to a more structured approach to events at the school. Some sort of organisational learning has also been introduced at the school. The realisation on the part of the staff that they now have their destiny in their own hands is an especially critical development. And whilst the vision is not a compelling force in the organisation, it has nevertheless produced some strategic focus at the school. The insights and skills they acquired concerning resource management will also stand them in good stead.
- Full Text:
- Date Issued: 2003
An investigation of the relative importance of the media in influencing the voting behaviour of Evelyn Hone College students in Lusaka during the December, 2001 presidential elections in Zambia
- Authors: Jere, Caesar
- Date: 2003
- Subjects: Voting -- Zambia Mass media -- Political aspects -- Zambia Presidents -- Zambia -- Election -- 2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3516 , http://hdl.handle.net/10962/d1007803
- Description: This study explores the relative importance of the media in influencing the electoral choices of a small group of Zambians, namely Evelyn Hone College students in Lusaka who participated in the December 2001 elections in Zambia. The study investigates the interplay of mediation between the lived cultural experiences of the sample of students and the impact of media messages. Students at Evelyn Hone College come from different ethnic groupings, social classes, religions and regions. They are exposed to both the state and the privately owned media, which represent a range of political viewpoints. The outcome of the December 2001 elections in Zambia gave the impression that people in urban areas in Zambia were less likely to vote on ethnic lines because they had easy access to different media, ranging from print to electronic, which provided them with diverse information about the political scene, and probably shaped their electoral choices. Conversely, their counterparts in the rural areas appeared to vote along ethnic lines, seemingly because of lack of exposure to the media. It was also assumed that most people in rural areas were not as modernized as their urban counterparts who were more exposed to enlightened sources of information such as professional groups and other elite social institutions which helped them to shape their political opinions than most rural people. The study attempts to establish to what extent the media impacted on the selected sample of urban students in the choice of their presidential candidates in the December 2001 elections in Zambia. The study further investigates to what extent other factors such as ethnic inclinations and other social predispositions influenced them in their choice of the candidates. The interviewees for this study were randomly drawn from a population of Evelyn Hone College students that voted in the December 2001 presidential elections in Zambia. The sample consisted of 30 randomly selected students who were purposely stratified in three focus groups of ten each. Each stratum represented the approximate ethnic equivalence of one of the presidential candidates who contested the December 2001 elections.
- Full Text:
- Date Issued: 2003
- Authors: Jere, Caesar
- Date: 2003
- Subjects: Voting -- Zambia Mass media -- Political aspects -- Zambia Presidents -- Zambia -- Election -- 2001
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3516 , http://hdl.handle.net/10962/d1007803
- Description: This study explores the relative importance of the media in influencing the electoral choices of a small group of Zambians, namely Evelyn Hone College students in Lusaka who participated in the December 2001 elections in Zambia. The study investigates the interplay of mediation between the lived cultural experiences of the sample of students and the impact of media messages. Students at Evelyn Hone College come from different ethnic groupings, social classes, religions and regions. They are exposed to both the state and the privately owned media, which represent a range of political viewpoints. The outcome of the December 2001 elections in Zambia gave the impression that people in urban areas in Zambia were less likely to vote on ethnic lines because they had easy access to different media, ranging from print to electronic, which provided them with diverse information about the political scene, and probably shaped their electoral choices. Conversely, their counterparts in the rural areas appeared to vote along ethnic lines, seemingly because of lack of exposure to the media. It was also assumed that most people in rural areas were not as modernized as their urban counterparts who were more exposed to enlightened sources of information such as professional groups and other elite social institutions which helped them to shape their political opinions than most rural people. The study attempts to establish to what extent the media impacted on the selected sample of urban students in the choice of their presidential candidates in the December 2001 elections in Zambia. The study further investigates to what extent other factors such as ethnic inclinations and other social predispositions influenced them in their choice of the candidates. The interviewees for this study were randomly drawn from a population of Evelyn Hone College students that voted in the December 2001 presidential elections in Zambia. The sample consisted of 30 randomly selected students who were purposely stratified in three focus groups of ten each. Each stratum represented the approximate ethnic equivalence of one of the presidential candidates who contested the December 2001 elections.
- Full Text:
- Date Issued: 2003
Pollination success in a deceptive orchid is enhanced by co-occurring rewarding magnet plants
- Johnson, Steven D, Peter, Craig I, Nilsson, L Anders, Agren, Jon
- Authors: Johnson, Steven D , Peter, Craig I , Nilsson, L Anders , Agren, Jon
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6520 , http://hdl.handle.net/10962/d1005949 , http://www.jstor.org/stable/3449962
- Description: It has been debated whether pollination success in nonrewarding plants that flower in association with nectar-producing plants will be diminished by competition for pollinator visits or, alternatively, enhanced through increased local abundance of pollinators (the magnet species effect). We experimentally evaluated these effects using the nonrewarding bumblebee-pollinated orchid Anacamptis morio and associated nectar-producing plants at a site in Sweden. Pollination success (estimated as pollen receipt and pollen removal) in A. morio was significantly greater for individuals translocated to patches of nectar-producing plants (Geum rivale and Allium schoenoprasum) than for individuals placed outside (similar to20 m away) such patches. These results provide support for the existence of a facilitative magnet species effect in the interaction between certain nectar plants and A. morio. To determine the spatial scale of these interactions, we correlated the visitation rate to flowers of A. morio with the density of sympatric nectar plants in 1-m(2) and 100-m(2) plots centered around groups of translocated plants, and at the level of whole meadows (similar to0.5-2 ha). Visitation rate to flowers of A. morio was not correlated with the 1-m(2) patch density of G. rivale and A. schoenoprasum, but showed a significant positive relationship with density of these nectar plants in 100-m(2) plots. In addition, visitation to flowers of A. morio was strongly and positively related to the density of A. schoenoprasum at the level of the meadow. Choice experiments showed that bees foraging on the purple flowers of A. schoenoprasum (a particularly effective magnet species) visit the purple flowers of A. morio more readily (47.6% of choices) than bees foraging on the yellow flowers of Lotus corniculatus (17% of choices). Overall similarity in flower color and shape may increase the probability that a pollinator will temporarily shift from a nectar-producing "magnet" plant to a nonrewarding plant. We discuss the possibility of a mimicry continuum between those orchids that exploit instinctive food-seeking behavior of pollinators and those that show an adaptive resemblance to nectar-producing plants.
- Full Text:
- Date Issued: 2003
- Authors: Johnson, Steven D , Peter, Craig I , Nilsson, L Anders , Agren, Jon
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6520 , http://hdl.handle.net/10962/d1005949 , http://www.jstor.org/stable/3449962
- Description: It has been debated whether pollination success in nonrewarding plants that flower in association with nectar-producing plants will be diminished by competition for pollinator visits or, alternatively, enhanced through increased local abundance of pollinators (the magnet species effect). We experimentally evaluated these effects using the nonrewarding bumblebee-pollinated orchid Anacamptis morio and associated nectar-producing plants at a site in Sweden. Pollination success (estimated as pollen receipt and pollen removal) in A. morio was significantly greater for individuals translocated to patches of nectar-producing plants (Geum rivale and Allium schoenoprasum) than for individuals placed outside (similar to20 m away) such patches. These results provide support for the existence of a facilitative magnet species effect in the interaction between certain nectar plants and A. morio. To determine the spatial scale of these interactions, we correlated the visitation rate to flowers of A. morio with the density of sympatric nectar plants in 1-m(2) and 100-m(2) plots centered around groups of translocated plants, and at the level of whole meadows (similar to0.5-2 ha). Visitation rate to flowers of A. morio was not correlated with the 1-m(2) patch density of G. rivale and A. schoenoprasum, but showed a significant positive relationship with density of these nectar plants in 100-m(2) plots. In addition, visitation to flowers of A. morio was strongly and positively related to the density of A. schoenoprasum at the level of the meadow. Choice experiments showed that bees foraging on the purple flowers of A. schoenoprasum (a particularly effective magnet species) visit the purple flowers of A. morio more readily (47.6% of choices) than bees foraging on the yellow flowers of Lotus corniculatus (17% of choices). Overall similarity in flower color and shape may increase the probability that a pollinator will temporarily shift from a nectar-producing "magnet" plant to a nonrewarding plant. We discuss the possibility of a mimicry continuum between those orchids that exploit instinctive food-seeking behavior of pollinators and those that show an adaptive resemblance to nectar-producing plants.
- Full Text:
- Date Issued: 2003
Intercohort cannibalism and parturition-associated behaviour of captive-bred swordtail, Xiphophorus helleri (Pisces: Poeciliidae)
- Jones, Clifford Louis Wilshire
- Authors: Jones, Clifford Louis Wilshire
- Date: 2003
- Subjects: Poeciliidae -- Behavior Xiphophorus helleri Fish culture
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5351 , http://hdl.handle.net/10962/d1007812
- Description: Adult fish that belong to the family Poeciliidae cannibalise juveniles, both in the wild and under captive conditions, but this behaviour has only been partly investigated in the Poeciliidae in some of the commercially valuable species. The objective of the research is to develop an understanding of intercohort cannibalism and parturition-associated behaviour in captive-bred swordtail (Xiphophorus helleri), with applications to industry and future research of other poeciliids. Experiments investigating the effect of adult stocking density and sex ratio on the production of juveniles were used to determine if cannibalism occurs under culture conditions. The average rate of intercohort cannibalism ranged from (5.5 to 53.9%), and was positively density dependent and independent of sex ratio, indicating that males and females were probably equally cannibalistic. The highest number of juveniles (1725.7±141.4) produced per tank over 70 days was obtained from two males and eight females. To develop a better understanding of adult and juvenile behaviour during parturition, fish were observed under controlled laboratory conditions using video and behaviours such as attack (burst of speed by an adult in the direction of a juvenile), escape (avoidance of cannibalism after attack) and cannibalism (predation of a live juvenile by an adult), for example, were identified. Under laboratory conditions most young escaped in downward direction after attack (49%) and most utilised the refuge made that was made available. Furthermore, most attacks (62-65%) and cannibalism (57-84%) occurred at the bottom. Since the presence of refuge significantly increased the rate of juvenile survival under culture conditions, it was hypothesised that the rate of cannibalism could be reduced under farming conditions if juveniles were protected when they escaped downwards. This hypothesis was accepted as it was found that refuge at the bottom of the water column or the inclusion of a false-bottom reduced the rate of cannibalism by 49% and 72%, respectively. Similarly, the hypothesise that the rate of cannibalism could be reduced if juveniles where given protection when escaping sideways (32% of juveniles escaped sideways in the laboratory) was also accepted when tested under farm-scale conditions because a false-side reduced the rate of cannibalism by an average of 45%. Since males and females were equally responsible for cannibalising juveniles in the laboratory, it was hypothesised that the rate of cannibalism would decrease proportionately with the removal of males (Le. 20% of the cannibals) from the population; the removal of males under farming conditions resulted in a 19.5% reduction in the rate of cannibalism. Since older juveniles were better able to escape cannibalism than neonates and since adults habituate to stimuli that previously resulted in attack behaviour, it was hypothesised that the rate of cannibalism would remain unaffected by the length of time that juveniles were exposed to adults in the breeding tanks. This hypothesis was also accepted when tested under farm conditions. However, some hypotheses based on laboratory observations were not accepted. For example, a constant low light intensity did not appear to decrease the rate of cannibalism under farm conditions; also, the occurrence of dead and deformed juveniles went unnoticed in the laboratory, and under farm conditions, where adults did not have access to the bottom of the tank, 10% of the harvest consisted of dead and deformed juveniles. It is concluded that technologies, such as bottom-refuge or a false-side, that increase the size of the liveharvest and allow for the removal of potentially less viable offspring are recommended for the commercial production of poeciliids. The overall similarity of X. helleri behaviour between the laboratory experiments and the farm-scale trials suggests that the post-partum behaviour of X. helleri remains consistent under these different conditions; thus, behaviour under one set of conditions may be used to predict behaviour under other conditions. The application and significance of extrapolations to industry and future research of X. helleri and possibly other poeciliids were discussed and the most applicable laboratory observations with the highest extrapolation capacity were proposed. Furthermore, techniques were developed to aid industry and future researchers in making predictions relating to behaviour of X. helleri under different conditions based on laboratory observations. The results were used to develop a model indicating that selection pressures against cannibalism are not likely to exist at the rate of cannibalism observed here since the potential genetic gain through kin survival and inclusive fitness was shown to be greater than any potential genetiC loss experienced by a victim of cannibalism. The model was successfully tested under a range of social conditions. Other possible explanations for cannibalism in poeciliids, such as parental manipulation, nutritional advantages, opportunistic predation and the recovery of energy are discussed. It is suggested that the most likely proximate cause of cannibalism under captive conditions is opportunistic predation. The theory that cannibalism ensures that only viable genes of the victim are expressed, through inclusive fitness, is a possible ultimate cause of cannibalism, which may have been inherited from feral ancestors of captive-bred X. helleri.
- Full Text:
- Date Issued: 2003
- Authors: Jones, Clifford Louis Wilshire
- Date: 2003
- Subjects: Poeciliidae -- Behavior Xiphophorus helleri Fish culture
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5351 , http://hdl.handle.net/10962/d1007812
- Description: Adult fish that belong to the family Poeciliidae cannibalise juveniles, both in the wild and under captive conditions, but this behaviour has only been partly investigated in the Poeciliidae in some of the commercially valuable species. The objective of the research is to develop an understanding of intercohort cannibalism and parturition-associated behaviour in captive-bred swordtail (Xiphophorus helleri), with applications to industry and future research of other poeciliids. Experiments investigating the effect of adult stocking density and sex ratio on the production of juveniles were used to determine if cannibalism occurs under culture conditions. The average rate of intercohort cannibalism ranged from (5.5 to 53.9%), and was positively density dependent and independent of sex ratio, indicating that males and females were probably equally cannibalistic. The highest number of juveniles (1725.7±141.4) produced per tank over 70 days was obtained from two males and eight females. To develop a better understanding of adult and juvenile behaviour during parturition, fish were observed under controlled laboratory conditions using video and behaviours such as attack (burst of speed by an adult in the direction of a juvenile), escape (avoidance of cannibalism after attack) and cannibalism (predation of a live juvenile by an adult), for example, were identified. Under laboratory conditions most young escaped in downward direction after attack (49%) and most utilised the refuge made that was made available. Furthermore, most attacks (62-65%) and cannibalism (57-84%) occurred at the bottom. Since the presence of refuge significantly increased the rate of juvenile survival under culture conditions, it was hypothesised that the rate of cannibalism could be reduced under farming conditions if juveniles were protected when they escaped downwards. This hypothesis was accepted as it was found that refuge at the bottom of the water column or the inclusion of a false-bottom reduced the rate of cannibalism by 49% and 72%, respectively. Similarly, the hypothesise that the rate of cannibalism could be reduced if juveniles where given protection when escaping sideways (32% of juveniles escaped sideways in the laboratory) was also accepted when tested under farm-scale conditions because a false-side reduced the rate of cannibalism by an average of 45%. Since males and females were equally responsible for cannibalising juveniles in the laboratory, it was hypothesised that the rate of cannibalism would decrease proportionately with the removal of males (Le. 20% of the cannibals) from the population; the removal of males under farming conditions resulted in a 19.5% reduction in the rate of cannibalism. Since older juveniles were better able to escape cannibalism than neonates and since adults habituate to stimuli that previously resulted in attack behaviour, it was hypothesised that the rate of cannibalism would remain unaffected by the length of time that juveniles were exposed to adults in the breeding tanks. This hypothesis was also accepted when tested under farm conditions. However, some hypotheses based on laboratory observations were not accepted. For example, a constant low light intensity did not appear to decrease the rate of cannibalism under farm conditions; also, the occurrence of dead and deformed juveniles went unnoticed in the laboratory, and under farm conditions, where adults did not have access to the bottom of the tank, 10% of the harvest consisted of dead and deformed juveniles. It is concluded that technologies, such as bottom-refuge or a false-side, that increase the size of the liveharvest and allow for the removal of potentially less viable offspring are recommended for the commercial production of poeciliids. The overall similarity of X. helleri behaviour between the laboratory experiments and the farm-scale trials suggests that the post-partum behaviour of X. helleri remains consistent under these different conditions; thus, behaviour under one set of conditions may be used to predict behaviour under other conditions. The application and significance of extrapolations to industry and future research of X. helleri and possibly other poeciliids were discussed and the most applicable laboratory observations with the highest extrapolation capacity were proposed. Furthermore, techniques were developed to aid industry and future researchers in making predictions relating to behaviour of X. helleri under different conditions based on laboratory observations. The results were used to develop a model indicating that selection pressures against cannibalism are not likely to exist at the rate of cannibalism observed here since the potential genetic gain through kin survival and inclusive fitness was shown to be greater than any potential genetiC loss experienced by a victim of cannibalism. The model was successfully tested under a range of social conditions. Other possible explanations for cannibalism in poeciliids, such as parental manipulation, nutritional advantages, opportunistic predation and the recovery of energy are discussed. It is suggested that the most likely proximate cause of cannibalism under captive conditions is opportunistic predation. The theory that cannibalism ensures that only viable genes of the victim are expressed, through inclusive fitness, is a possible ultimate cause of cannibalism, which may have been inherited from feral ancestors of captive-bred X. helleri.
- Full Text:
- Date Issued: 2003
An assessment of bait availability, utilization and management guidelines in Eastern Cape estuaries
- Authors: Jooste, Jakobus Gerrit
- Date: 2003
- Subjects: Upogebia african -- Effects of sediments on -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishing baits -- Conservation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:11073 , http://hdl.handle.net/10948/334 , Upogebia african -- Effects of sediments on -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishing baits -- Conservation -- South Africa -- Eastern Cape
- Description: Aspects around the management of benthic soft sediment bait organisms, with special focus on the mud prawn (Upogebia africana) of eastern Cape estuaries was investigated. The recreational linefishery of the Gamtoos estuary was described, and compared to previous studies. Target fish species was identified, and a large dependency on bait sourced from estuaries needed for the capture of these species was noted, especially for spotted grunter (Pomadasys commersonnii). A comparison between bait use, success and the natural diet of target fish species was also made. The structure and distribution of sediments in the old channel mud banks was described and compared with historical data. The influence of sediments on mud prawn distribution was investigated, but no significant interactions were found at the study site. The impacts of once-off pumping and digging events, and monthly trampling on the sediments and mud prawn population was studied over a 7-month period. Initial removal rates as well as recovery time varied significantly between the two collection methods, while the largest decline in prawn numbers (to zero) with no recovery visible after seven months was caused by trampling. All disturbances caused some alteration in sediment composition, but not to such an extent that the sediments became unfavorable for mud prawns. Trampling did, however, result in the compaction of sediments to such a degree that prawns could not construct burrows. Issues around current removal quotas of bait species as well as the creation of a small-scale commercial (SSC) bait selling operation at Swartkops estuary were critically evaluated, and suggestions for the future removal rates of mud prawns based on production export calculations were made. The distribution, size, sex ratios and number of gravid females occurring along a tidal gradient as well as along horizontal gradient of the mud bank during growth (January – March) and reproductive (September – October) periods was investigated. Changes in the distribution of females between the two study periods were significant, while the distribution of reproductively active females were closely linked to the low water mark (Lower tidal levels). Females occurring in this zone were also significantly larger than females occurring towards the back of the study site. Some minor changes along the horizontal gradient were also observed. The sediment compos ition of the mud bank was found not to play a role in this distribution, leading to the suggestion that exposure to ebb and flood tide currents could influence female prawn distributions. Management recommendations based on these observations were made.
- Full Text:
- Date Issued: 2003
- Authors: Jooste, Jakobus Gerrit
- Date: 2003
- Subjects: Upogebia african -- Effects of sediments on -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishing baits -- Conservation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:11073 , http://hdl.handle.net/10948/334 , Upogebia african -- Effects of sediments on -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishing baits -- Conservation -- South Africa -- Eastern Cape
- Description: Aspects around the management of benthic soft sediment bait organisms, with special focus on the mud prawn (Upogebia africana) of eastern Cape estuaries was investigated. The recreational linefishery of the Gamtoos estuary was described, and compared to previous studies. Target fish species was identified, and a large dependency on bait sourced from estuaries needed for the capture of these species was noted, especially for spotted grunter (Pomadasys commersonnii). A comparison between bait use, success and the natural diet of target fish species was also made. The structure and distribution of sediments in the old channel mud banks was described and compared with historical data. The influence of sediments on mud prawn distribution was investigated, but no significant interactions were found at the study site. The impacts of once-off pumping and digging events, and monthly trampling on the sediments and mud prawn population was studied over a 7-month period. Initial removal rates as well as recovery time varied significantly between the two collection methods, while the largest decline in prawn numbers (to zero) with no recovery visible after seven months was caused by trampling. All disturbances caused some alteration in sediment composition, but not to such an extent that the sediments became unfavorable for mud prawns. Trampling did, however, result in the compaction of sediments to such a degree that prawns could not construct burrows. Issues around current removal quotas of bait species as well as the creation of a small-scale commercial (SSC) bait selling operation at Swartkops estuary were critically evaluated, and suggestions for the future removal rates of mud prawns based on production export calculations were made. The distribution, size, sex ratios and number of gravid females occurring along a tidal gradient as well as along horizontal gradient of the mud bank during growth (January – March) and reproductive (September – October) periods was investigated. Changes in the distribution of females between the two study periods were significant, while the distribution of reproductively active females were closely linked to the low water mark (Lower tidal levels). Females occurring in this zone were also significantly larger than females occurring towards the back of the study site. Some minor changes along the horizontal gradient were also observed. The sediment compos ition of the mud bank was found not to play a role in this distribution, leading to the suggestion that exposure to ebb and flood tide currents could influence female prawn distributions. Management recommendations based on these observations were made.
- Full Text:
- Date Issued: 2003
Grade six and seven learners' perceptions of the HIV/AIDS life skills education programme
- Authors: Julies, Zainuneesa
- Date: 2003
- Subjects: AIDS (Disease) -- Study and teaching (Primary) -- South Africa -- Evaluation , AIDS (Disease) -- South Africa -- Prevention
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10988 , http://hdl.handle.net/10948/315 , AIDS (Disease) -- Study and teaching (Primary) -- South Africa -- Evaluation , AIDS (Disease) -- South Africa -- Prevention
- Description: At present there is no cure or vaccine for Human Immuno-deficiency Virus (HIV) or Acquired Immune Deficiency Syndrome (AIDS) therefore prevention programmes are seen as the only means of reducing the spread of the disease. HIV/AIDS education programmes in schools have been identified as the most effective intervention because billions of children can be reached worldwide and because schools are the one social institution with which most children come into contact. Young people in particular have been identified as the age group most in need of a preventative programme. The aim of this study is to explore the perceptions of grade six and seven learners with regard to the Life Skills programme focusing on HIV/AIDS education in the Port Elizabeth region. In order to fulfill the above aim a qualitative study was undertaken within an exploratory descriptive approach. A non-probability, convenient sample of six schools were selected. Focus groups, utilising an unstructured interview, were used to gather qualitative data about the perceptions of grade six and seven learners. The focus groups consisted of 10-12 participants. The data was thematically analysed using Tesch’s approach. The major findings of the present study included the following: 1. Learners’ perceptions of completing the questionnaire were generally positive in nature. Negative perceptions related to practical issues such as the length of the questionnaire and the time of administration. 2. Learner’s perceptions of the programme were generally positive. 3. Learners’ felt more comfortable discussing HIV/AIDS with parents and teachers. xi 4. Learners’ appeared to be well informed about high-risk behaviour related to HIV/AIDS and existing myths. 5. Contact with HIV+ people is non-existent. However, learner’s felt that the programme had fostered positive attitudes towards HIV+ people. 6. Learner’s felt that schools had an important role to play in sharing information about HIV/AIDS. These findings seem to indicate positive outcomes for the programme as a whole, in that is was successful in terms of conveying information regarding HIV/AIDS; it led to positive changes in attitudes, especially towards HIV+ people; and it confirmed the school as the best setting for implementing HIV/AIDS Life Skills programmes.
- Full Text:
- Date Issued: 2003
- Authors: Julies, Zainuneesa
- Date: 2003
- Subjects: AIDS (Disease) -- Study and teaching (Primary) -- South Africa -- Evaluation , AIDS (Disease) -- South Africa -- Prevention
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10988 , http://hdl.handle.net/10948/315 , AIDS (Disease) -- Study and teaching (Primary) -- South Africa -- Evaluation , AIDS (Disease) -- South Africa -- Prevention
- Description: At present there is no cure or vaccine for Human Immuno-deficiency Virus (HIV) or Acquired Immune Deficiency Syndrome (AIDS) therefore prevention programmes are seen as the only means of reducing the spread of the disease. HIV/AIDS education programmes in schools have been identified as the most effective intervention because billions of children can be reached worldwide and because schools are the one social institution with which most children come into contact. Young people in particular have been identified as the age group most in need of a preventative programme. The aim of this study is to explore the perceptions of grade six and seven learners with regard to the Life Skills programme focusing on HIV/AIDS education in the Port Elizabeth region. In order to fulfill the above aim a qualitative study was undertaken within an exploratory descriptive approach. A non-probability, convenient sample of six schools were selected. Focus groups, utilising an unstructured interview, were used to gather qualitative data about the perceptions of grade six and seven learners. The focus groups consisted of 10-12 participants. The data was thematically analysed using Tesch’s approach. The major findings of the present study included the following: 1. Learners’ perceptions of completing the questionnaire were generally positive in nature. Negative perceptions related to practical issues such as the length of the questionnaire and the time of administration. 2. Learner’s perceptions of the programme were generally positive. 3. Learners’ felt more comfortable discussing HIV/AIDS with parents and teachers. xi 4. Learners’ appeared to be well informed about high-risk behaviour related to HIV/AIDS and existing myths. 5. Contact with HIV+ people is non-existent. However, learner’s felt that the programme had fostered positive attitudes towards HIV+ people. 6. Learner’s felt that schools had an important role to play in sharing information about HIV/AIDS. These findings seem to indicate positive outcomes for the programme as a whole, in that is was successful in terms of conveying information regarding HIV/AIDS; it led to positive changes in attitudes, especially towards HIV+ people; and it confirmed the school as the best setting for implementing HIV/AIDS Life Skills programmes.
- Full Text:
- Date Issued: 2003
A critical investigation of managing the standards development process for the life insurance industry in Namibia
- Authors: Kaimu, Himeesora Irene
- Date: 2003
- Subjects: Life insurance -- Management -- Namibia Insurance -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1481 , http://hdl.handle.net/10962/d1003362
- Description: The development of standards for education and training is regarded as a very important activity by many countries. Any country that sets standards for education and training is trying to define its training system and avoid duplication of training by providers who do not see eye to eye. National standards are public documents accessible to anyone interested in education and training. Namibia introduced standards setting as a core activity of administering the National Qualifications Framework in 1996 after the passing of the Namibia Qualifications Act by parliament. This research attempts to gain an understanding of how the process of developing standards for the Life Assurance Sector in Namibia was managed by focusing on the experiences of three persons who took part in the process of developing the said standards. The case study approach enabled me to gain considerable insight into management issues that may have influenced the process of developing these specific standards. The findings illuminate the management and leadership issues which characterised the process for the LA Industry. Several management issues emerge as key elements in the process. These include: A strong emphasis on transformational leadership through clear vision crafting; empowerment through emancipatory thinking; OD features such as problem solving and effective communication; the importance of organisational structure; the concept of a learning organisation and benchmarking as well as collegiality. This research explores the relationship between management thinking generally, and the management of the standards development process in particular.
- Full Text:
- Date Issued: 2003
- Authors: Kaimu, Himeesora Irene
- Date: 2003
- Subjects: Life insurance -- Management -- Namibia Insurance -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1481 , http://hdl.handle.net/10962/d1003362
- Description: The development of standards for education and training is regarded as a very important activity by many countries. Any country that sets standards for education and training is trying to define its training system and avoid duplication of training by providers who do not see eye to eye. National standards are public documents accessible to anyone interested in education and training. Namibia introduced standards setting as a core activity of administering the National Qualifications Framework in 1996 after the passing of the Namibia Qualifications Act by parliament. This research attempts to gain an understanding of how the process of developing standards for the Life Assurance Sector in Namibia was managed by focusing on the experiences of three persons who took part in the process of developing the said standards. The case study approach enabled me to gain considerable insight into management issues that may have influenced the process of developing these specific standards. The findings illuminate the management and leadership issues which characterised the process for the LA Industry. Several management issues emerge as key elements in the process. These include: A strong emphasis on transformational leadership through clear vision crafting; empowerment through emancipatory thinking; OD features such as problem solving and effective communication; the importance of organisational structure; the concept of a learning organisation and benchmarking as well as collegiality. This research explores the relationship between management thinking generally, and the management of the standards development process in particular.
- Full Text:
- Date Issued: 2003
Putting participatory communication into practice through community radio: a case study of how policies on programming and production are formulated and implemented at Radio Graaff-Reinet
- Kanyegirire, Andrew Steve Tumuhirwe
- Authors: Kanyegirire, Andrew Steve Tumuhirwe
- Date: 2003
- Subjects: Radio broadcasting -- South Africa -- Graaff-Reinet , Radio in community development , Radio stations -- South Africa -- Graaff-Reinet -- Management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3442 , http://hdl.handle.net/10962/d1002896 , Radio broadcasting -- South Africa -- Graaff-Reinet , Radio in community development , Radio stations -- South Africa -- Graaff-Reinet -- Management
- Description: In the South African (SA) model of community radio, listeners are expected to be in charge of the management and programming operations of stations. This study tests the SA model against the actual conditions at an existing station. For this purpose, the study focuses on Radio Graaff-Reinet, a community radio station in the Eastern Cape. Emphasis is on examining the extent to which members of the station’s target community are involved in its operations. The study first assesses the nature of this involvement, keeping in mind the principles of, ‘community ownership’ and ‘participatory programming’ on which the SA model of community radio is based. It is argued that the station does provide a valuable ‘public sphere’ for its listeners. The potential of this sphere remains limited, however, due to the impact of ongoing power struggles around the ownership of the station. The lack of proper systems for managing these struggles has contributed to the fact that the station continues to be in a constant state of flux, with a high turnover of staff and regular changes in its policies and strategies. The study argues that, until such systems are put in place, the principles of community ownership will not be fully realizable. Areas in which the struggle over ownership plays itself out can be identified in the relationship between the station’s Board of Directors and its managing staff, between one particular station manager and her staff and between the station and its target community. These struggles often take place in context of a debate about the financial sustainability of the station versus its developmental aims. It is argued that this opposition needs to be questioned since, until the station is financially stable, it will remain vulnerable to interference by powerful individuals and groups in its attempts to establish such developmental aims. The study then goes on to identify key weaknesses in the station’s approach to community ownership and participation. In particular, it is pointed out that various stakeholders in the station have contradictory understandings of what is meant by ‘community’, using the term to include or exclude sections of the Graaff-Reinet society in very different ways. There are also very different understandings at play about the concept of community radio itself. These contradictions have an impact on the station’s ability to implement participatory programming. This situation is exacerbated by the fact that the station does not have a consistent forum in which shared decision-making can take place. Consequently, the station also remains unable to draw effectively on its own volunteer staff and on its community as resources for programming content. Finally, the study explores the broader significance of the weaknesses that exist in the case of Graaff-Reinet, arguing that these are problems that repeat themselves throughout the South African community radio sector. Possible strategies for addressing these problems are suggested, including approaches to monitoring and research, training, organizational development and advocacy.
- Full Text:
- Date Issued: 2003
- Authors: Kanyegirire, Andrew Steve Tumuhirwe
- Date: 2003
- Subjects: Radio broadcasting -- South Africa -- Graaff-Reinet , Radio in community development , Radio stations -- South Africa -- Graaff-Reinet -- Management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3442 , http://hdl.handle.net/10962/d1002896 , Radio broadcasting -- South Africa -- Graaff-Reinet , Radio in community development , Radio stations -- South Africa -- Graaff-Reinet -- Management
- Description: In the South African (SA) model of community radio, listeners are expected to be in charge of the management and programming operations of stations. This study tests the SA model against the actual conditions at an existing station. For this purpose, the study focuses on Radio Graaff-Reinet, a community radio station in the Eastern Cape. Emphasis is on examining the extent to which members of the station’s target community are involved in its operations. The study first assesses the nature of this involvement, keeping in mind the principles of, ‘community ownership’ and ‘participatory programming’ on which the SA model of community radio is based. It is argued that the station does provide a valuable ‘public sphere’ for its listeners. The potential of this sphere remains limited, however, due to the impact of ongoing power struggles around the ownership of the station. The lack of proper systems for managing these struggles has contributed to the fact that the station continues to be in a constant state of flux, with a high turnover of staff and regular changes in its policies and strategies. The study argues that, until such systems are put in place, the principles of community ownership will not be fully realizable. Areas in which the struggle over ownership plays itself out can be identified in the relationship between the station’s Board of Directors and its managing staff, between one particular station manager and her staff and between the station and its target community. These struggles often take place in context of a debate about the financial sustainability of the station versus its developmental aims. It is argued that this opposition needs to be questioned since, until the station is financially stable, it will remain vulnerable to interference by powerful individuals and groups in its attempts to establish such developmental aims. The study then goes on to identify key weaknesses in the station’s approach to community ownership and participation. In particular, it is pointed out that various stakeholders in the station have contradictory understandings of what is meant by ‘community’, using the term to include or exclude sections of the Graaff-Reinet society in very different ways. There are also very different understandings at play about the concept of community radio itself. These contradictions have an impact on the station’s ability to implement participatory programming. This situation is exacerbated by the fact that the station does not have a consistent forum in which shared decision-making can take place. Consequently, the station also remains unable to draw effectively on its own volunteer staff and on its community as resources for programming content. Finally, the study explores the broader significance of the weaknesses that exist in the case of Graaff-Reinet, arguing that these are problems that repeat themselves throughout the South African community radio sector. Possible strategies for addressing these problems are suggested, including approaches to monitoring and research, training, organizational development and advocacy.
- Full Text:
- Date Issued: 2003