Productivity and abundance of Sclerocarya birrea subsp. caffra in and around rural settlements and protected areas of the Bushbuckridge lowveld, South Africa
- Shackleton, Charlie M, Botha, Jenny, Emanuel, P L
- Authors: Shackleton, Charlie M , Botha, Jenny , Emanuel, P L
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181607 , vital:43751 , xlink:href="https://doi.org/10.1080/14728028.2003.9752459"
- Description: Sclerocarya birrea (A. Rich.) Hochst, subsp. caffra (Sond.) Kokwaro is a common species throughout the semi-arid savannas of southern Africa, and is sought after by rural communities. It is frequently maintained in homesteads and fields in an agroforestry situation. It has also been identified by a number of international and national institutes as a key species for domestication and commercialisation. Yet, the sustainability of the resource and local user knowledge and practices have not been considered. This study reports on the abundance and productivity of S. birrea in four rural villages and neighbouring protected areas in the Bushbuckridge lowveld of the Limpopo Province, South Africa, where its common name is marula. The density of marula stems was measured in homestead plots, arable fields and the surrounding communal rangelands of each village. Fruit production was assessed by regular counting of fruit fall from marked trees of known size. Within the villages, fruit production was monitored via local community groups. Additional monitoring of fruiting was conducted on marked trees within local protected areas. The proportion of households planting or nurturing marula trees was determined through interviews with a stratified random sample of households. The density of marula trees was significantly higher in protected areas than the neighbouring communal lands, fields or homesteads. However, the majority of trees in protected areas were small, while those in homesteads were large and mature. Density of adult fruit-bearing female trees, was similar between the protected areas and homesteads, but less in fields and communal lands. S. birrea trees were maintained in 79 % of homesteads and 58 % of fields. Mean fruit yield per tree was significantly higher from village trees (less than 17 000 fruits) than protected area trees (more than 3 500 fruits), even after accounting for differences in tree size. The fresh mass of individual fruits was also greater on village trees than on trees in protected areas. Both these characteristics suggest some degree of historical selection of the trees in the homesteads and fields. There was a positive relationship between tree size and number of fruits produced.
- Full Text:
- Date Issued: 2003
- Authors: Shackleton, Charlie M , Botha, Jenny , Emanuel, P L
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181607 , vital:43751 , xlink:href="https://doi.org/10.1080/14728028.2003.9752459"
- Description: Sclerocarya birrea (A. Rich.) Hochst, subsp. caffra (Sond.) Kokwaro is a common species throughout the semi-arid savannas of southern Africa, and is sought after by rural communities. It is frequently maintained in homesteads and fields in an agroforestry situation. It has also been identified by a number of international and national institutes as a key species for domestication and commercialisation. Yet, the sustainability of the resource and local user knowledge and practices have not been considered. This study reports on the abundance and productivity of S. birrea in four rural villages and neighbouring protected areas in the Bushbuckridge lowveld of the Limpopo Province, South Africa, where its common name is marula. The density of marula stems was measured in homestead plots, arable fields and the surrounding communal rangelands of each village. Fruit production was assessed by regular counting of fruit fall from marked trees of known size. Within the villages, fruit production was monitored via local community groups. Additional monitoring of fruiting was conducted on marked trees within local protected areas. The proportion of households planting or nurturing marula trees was determined through interviews with a stratified random sample of households. The density of marula trees was significantly higher in protected areas than the neighbouring communal lands, fields or homesteads. However, the majority of trees in protected areas were small, while those in homesteads were large and mature. Density of adult fruit-bearing female trees, was similar between the protected areas and homesteads, but less in fields and communal lands. S. birrea trees were maintained in 79 % of homesteads and 58 % of fields. Mean fruit yield per tree was significantly higher from village trees (less than 17 000 fruits) than protected area trees (more than 3 500 fruits), even after accounting for differences in tree size. The fresh mass of individual fruits was also greater on village trees than on trees in protected areas. Both these characteristics suggest some degree of historical selection of the trees in the homesteads and fields. There was a positive relationship between tree size and number of fruits produced.
- Full Text:
- Date Issued: 2003
Progress towards the development and implementation of an unambiguous copper wire fingerprinting system
- Authors: Poole, Martin
- Date: 2003
- Subjects: Electroplating , Copper , Telecommunication , Theft -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5484 , http://hdl.handle.net/10962/d1005270 , Electroplating , Copper , Telecommunication , Theft -- Prevention
- Description: The Telecommunications industry in Southern Africa is faced with the problem of theft of the signal carrying copper wire, both from the ground and from telephone poles. In many cases, if the offenders are caught, the prosecuting party has no way of proving that the wire is the property of any one Telecommunication company, as any inked markings on the insulating sheaths have been burned off along with the insulation and protective coatings themselves. Through this work we * describe the problem, * specify the necessary and preferred technical properties of a viable solution, * report the preliminary investigations into the devising of an unambiguous "fingerprinting" of the 0.5 mm wires, including some of those solutions that, upon investigation, appear non-viable, * describe the development and implementation of an electrochemical marker with detection mechanism which has shown in proof-of-principle to work, * outline the road-map of necessary future work.
- Full Text:
- Date Issued: 2003
- Authors: Poole, Martin
- Date: 2003
- Subjects: Electroplating , Copper , Telecommunication , Theft -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5484 , http://hdl.handle.net/10962/d1005270 , Electroplating , Copper , Telecommunication , Theft -- Prevention
- Description: The Telecommunications industry in Southern Africa is faced with the problem of theft of the signal carrying copper wire, both from the ground and from telephone poles. In many cases, if the offenders are caught, the prosecuting party has no way of proving that the wire is the property of any one Telecommunication company, as any inked markings on the insulating sheaths have been burned off along with the insulation and protective coatings themselves. Through this work we * describe the problem, * specify the necessary and preferred technical properties of a viable solution, * report the preliminary investigations into the devising of an unambiguous "fingerprinting" of the 0.5 mm wires, including some of those solutions that, upon investigation, appear non-viable, * describe the development and implementation of an electrochemical marker with detection mechanism which has shown in proof-of-principle to work, * outline the road-map of necessary future work.
- Full Text:
- Date Issued: 2003
Provocation as a defence in English and South African criminal law
- Authors: Krause, Samantha
- Date: 2003
- Subjects: Provocation (Criminal law) -- South Africa , Provocation (Criminal law) -- Great Britain
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11044 , http://hdl.handle.net/10948/310 , Provocation (Criminal law) -- South Africa , Provocation (Criminal law) -- Great Britain
- Description: In the past 20 years the defence of provocation has shifted from the periphery of South African law to a fully developed defence available to those who kill when provoked. Not only is the defence available to the provoked, but it has been extended to those who kill when subjected to emotional stress. However, the defence is mirred in controversy and bad decisions. Not only has the precise nature of the defence not been clarified, but this lack of clarity has been exacerbated by confusing decisions of our courts. This confusion is partly a result of the development of the defence of incapacity, particularly its extension to cases involving provocation and mental stress, and partly a result of its application in practice. Three major problems have plagued the provocation defence. Firstly, the courts have confused the defence of sane automatism with that of non-pathological incapacity. Secondly, there has been an implied use of an objective test in determining criminal incapacity where the enquiry has clearly been a subjective one. Thirdly, it has been held that the problem may not so much be the subjective aspect of provocation, but rather its application. The real problem seems to lie in the theoretical confusion as to the precise meaning of lack of “selfcontrol”. Lastly, on occasion the courts have failed to distinguish lack of capacity from diminished responsibility. Thus, in order to gain clarity concerning this “grey” area of the law these problems have created, it is necessary for South African law to consult more authoritative sources to receive guidance for the problems identified. One of those sources that has been consulted is that of English law. English law, however, deals with the defence of provocation in a different manner. Raising a defence of provocation here does not result in an acquittal but rather in a reduction of the charge to manslaughter. However, the English law on provocation is also 7 plagued by various problems. Firstly, there is the issue of cumulative provocation. Generally, there is little difficulty in cases where there is no “immediate trigger”. Secondly, the fundamental flaw with the current test of the reasonable man is that the courts have had to swing between the two aims of taking a compassionate view of human frailty while endeavoring to maintain an objective standard of the reasonable man. Lastly, it can be said that the problem with the proportionality requirement is that it makes the provocation defence dependant upon the assessment of the accused’s conduct after he or she lost his or her selfcontrol rather than on his or her giving way to passion and losing control in the first place. It is clear that from the problems identified in both South African law and English law concerning the defence of provocation the courts in each jurisdiction will have to pay careful attentio n to the problems highlighted and apply the law in such a way so as to ensure clarity and legal certainty.
- Full Text:
- Date Issued: 2003
- Authors: Krause, Samantha
- Date: 2003
- Subjects: Provocation (Criminal law) -- South Africa , Provocation (Criminal law) -- Great Britain
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11044 , http://hdl.handle.net/10948/310 , Provocation (Criminal law) -- South Africa , Provocation (Criminal law) -- Great Britain
- Description: In the past 20 years the defence of provocation has shifted from the periphery of South African law to a fully developed defence available to those who kill when provoked. Not only is the defence available to the provoked, but it has been extended to those who kill when subjected to emotional stress. However, the defence is mirred in controversy and bad decisions. Not only has the precise nature of the defence not been clarified, but this lack of clarity has been exacerbated by confusing decisions of our courts. This confusion is partly a result of the development of the defence of incapacity, particularly its extension to cases involving provocation and mental stress, and partly a result of its application in practice. Three major problems have plagued the provocation defence. Firstly, the courts have confused the defence of sane automatism with that of non-pathological incapacity. Secondly, there has been an implied use of an objective test in determining criminal incapacity where the enquiry has clearly been a subjective one. Thirdly, it has been held that the problem may not so much be the subjective aspect of provocation, but rather its application. The real problem seems to lie in the theoretical confusion as to the precise meaning of lack of “selfcontrol”. Lastly, on occasion the courts have failed to distinguish lack of capacity from diminished responsibility. Thus, in order to gain clarity concerning this “grey” area of the law these problems have created, it is necessary for South African law to consult more authoritative sources to receive guidance for the problems identified. One of those sources that has been consulted is that of English law. English law, however, deals with the defence of provocation in a different manner. Raising a defence of provocation here does not result in an acquittal but rather in a reduction of the charge to manslaughter. However, the English law on provocation is also 7 plagued by various problems. Firstly, there is the issue of cumulative provocation. Generally, there is little difficulty in cases where there is no “immediate trigger”. Secondly, the fundamental flaw with the current test of the reasonable man is that the courts have had to swing between the two aims of taking a compassionate view of human frailty while endeavoring to maintain an objective standard of the reasonable man. Lastly, it can be said that the problem with the proportionality requirement is that it makes the provocation defence dependant upon the assessment of the accused’s conduct after he or she lost his or her selfcontrol rather than on his or her giving way to passion and losing control in the first place. It is clear that from the problems identified in both South African law and English law concerning the defence of provocation the courts in each jurisdiction will have to pay careful attentio n to the problems highlighted and apply the law in such a way so as to ensure clarity and legal certainty.
- Full Text:
- Date Issued: 2003
Psycho-medical discourse in South African research on teenage pregnancy
- Macleod, Catriona I, Durrheim, Kevin
- Authors: Macleod, Catriona I , Durrheim, Kevin
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6257 , http://hdl.handle.net/10962/d1007875
- Description: Catriona Macleod and Kevin Durrheim apply a Foucauldian analysis to the scientific literature on teenage pregnancy.
- Full Text:
- Date Issued: 2003
- Authors: Macleod, Catriona I , Durrheim, Kevin
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6257 , http://hdl.handle.net/10962/d1007875
- Description: Catriona Macleod and Kevin Durrheim apply a Foucauldian analysis to the scientific literature on teenage pregnancy.
- Full Text:
- Date Issued: 2003
Psychoanalysis and realism
- Rae, Andrew Kenneth McKenzie
- Authors: Rae, Andrew Kenneth McKenzie
- Date: 2003
- Subjects: Psychoanalysis Realism Human beings -- Psychology International relations -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2825 , http://hdl.handle.net/10962/d1003035
- Description: International politics has always been characterised by conflict. This has been true regardless of the political systems in place or of any specific time in the history of humanity. Inter-state conflict exists today despite the fact that the vast majority of the states of the world are members of the United Nations and signatories to various treaties aimed at removing conflict as a means of state action. The realist school of thought argues that the international system is characterised by continual state conflict, caused by competition over scarce resources. The propensity towards conflict is argued to be an essential characteristic of human nature and, as such, human nature is considered to be aggressive and conflictual. Thus, for the realist, inter-state competition, coupled with aggressive human nature, constitutes the primary cause of interstate conflict. This thesis aims to examine two criticisms of the realist position in depth. The first concerns the attribution of human nature to states. This logical progression is problematic because it creates a type of „state-nature‟ that cannot be defended without providing a logical link between the individual, the group and the state. It is therefore an aim of this thesis to provide this link, using methodological individualism, in order to provide a basis for the attribution of human nature to states. The second aim of this thesis is to examine the notion of human nature that is offered by the realists. It is not enough to claim that human nature is aggressive and conflictual merely because conflict has characterised international relations throughout history. Rather, one should examine the individual‟s psychological development, in order to gain an understanding of aggressive instincts apparent in human nature. The thesis therefore examines psychoanalysis in order to attempt an understanding both of human nature, and of the conditions under which human nature may manifest itself in an aggressive, conflictual manner. The intention of this thesis, then, is to provide a defence of political realism, highlighting the shortcomings of the two criticisms outlined above.
- Full Text:
- Date Issued: 2003
- Authors: Rae, Andrew Kenneth McKenzie
- Date: 2003
- Subjects: Psychoanalysis Realism Human beings -- Psychology International relations -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2825 , http://hdl.handle.net/10962/d1003035
- Description: International politics has always been characterised by conflict. This has been true regardless of the political systems in place or of any specific time in the history of humanity. Inter-state conflict exists today despite the fact that the vast majority of the states of the world are members of the United Nations and signatories to various treaties aimed at removing conflict as a means of state action. The realist school of thought argues that the international system is characterised by continual state conflict, caused by competition over scarce resources. The propensity towards conflict is argued to be an essential characteristic of human nature and, as such, human nature is considered to be aggressive and conflictual. Thus, for the realist, inter-state competition, coupled with aggressive human nature, constitutes the primary cause of interstate conflict. This thesis aims to examine two criticisms of the realist position in depth. The first concerns the attribution of human nature to states. This logical progression is problematic because it creates a type of „state-nature‟ that cannot be defended without providing a logical link between the individual, the group and the state. It is therefore an aim of this thesis to provide this link, using methodological individualism, in order to provide a basis for the attribution of human nature to states. The second aim of this thesis is to examine the notion of human nature that is offered by the realists. It is not enough to claim that human nature is aggressive and conflictual merely because conflict has characterised international relations throughout history. Rather, one should examine the individual‟s psychological development, in order to gain an understanding of aggressive instincts apparent in human nature. The thesis therefore examines psychoanalysis in order to attempt an understanding both of human nature, and of the conditions under which human nature may manifest itself in an aggressive, conflictual manner. The intention of this thesis, then, is to provide a defence of political realism, highlighting the shortcomings of the two criticisms outlined above.
- 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
Pyrroloiminoquinone metabolites from South African Latrunculid sponges
- Authors: Antunes, Edith Martins
- Date: 2003
- Subjects: Sponges -- South Africa PQQ (Biochemistry) Marine metabolites -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4340 , http://hdl.handle.net/10962/d1005001
- Description: An in depth chemical investigation of the major and minor pyrroloiminoquinone metabolites produced by four species of endemic South African Latrunculid sponges, collected from Algoa Bay and the Tsitsikamma Marine Reserve off the south eastern coast of South Africa, yielded eleven new and twelve known pyrroloiminoquinone metabolites. The structures of the new metabolites were determined using standard spectroscopic techniques. Tsitsikamma pedunculata was shown to contain 7,8-dehydro-3-dihydro-discorhabdin C (2.1), 14-bromo-7,8-dehydro-3-dihydro-discorhabdin C (2.2), discorhabdin S (2.3), 14-bromo-1-hydroxy-discorhabdin S (2.4), 1-bromo-2-hydroxy-4-debromo-discorhabdin S (2.5), and 2,4-debromo-3-dihydro-discorhabdin C (2.6), together with the known compounds 14-bromo-discorhabdin C (1.51), 14-bromo-3-dihydro-discorhabdin C (1.52) and 3-dihydro-discorhabdin C. The metabolites from T. pedunculata were characterised by the presence of a reduced C-3 carbonyl and bromination at C-14. Compounds isolated from a second Latrunculid sponge, Latrunculia lorii, ranged from a substituted bicyclic pyrrolecarboxylic acid, makaluvic acid A (1.47), to the simple tricyclic known pyrroloiminoquinones makaluvamine C (1.33) and damirone B (1.20) and the more complex discorhabdin D type metabolites, discorhabdin M (3.2), 1-amino discorhabdin D (3.3), 1-methoxy discorhabdin D (3.4) and 1-alanyl discorhabdin D (3.5). Discorhabdin G* (3.1) was also isolated and characterised. This is the first reported occurrence of the known compounds 1.20, 1.33 and 1.47 in a Latrunculia sponge. Discorhabdin and bis-pyrroloiminoquinone type compounds predominated in Tsitsikamma favus. Three known, tsitsikammamines A (1.71) and B (1.72), 1.52, and five new pyrroloiminoquinones, tsitsikammamine N-oxime (4.1), tsitsikammamine B N-oxime (4.2), 2.1, 2.4 and 2.6, were isolated from this sponge. A fourth Latrunculid sponge (Strongylodesma sp.) yielded three known compounds, discorhabdins A (1.57), D (1.61) and 1.53, and one new pyrroloiminoquinone 3.3. The dual role of these metabolites as cytotoxic agents and pigments resulted in an attempt to relate the photochemical properties of these metabolites to their cytotoxicity. The pyrroloiminoquinone metabolites studied exhibited moderate singlet oxygen quantum yields, while three compounds (1.57, 4.1 and 4.2) were shown to be capable of producing radicals at a wavelength of 532 nm. The possibility of a correlation between the electrochemical properties and anti-cancer (HCT-116) activity of selected pyrroloiminoquinones was explored. A study of the oesophageal and ovarian cytotoxicities of two pyrroloiminoquinones (1.57 and 1.72), together with an investigation into the intercalation and topoisomerase I inhibitory activity of the bis-pyrroloiminoquinones (1.71, 1.72, 4.1 and 4.2), are presented.
- Full Text:
- Date Issued: 2003
- Authors: Antunes, Edith Martins
- Date: 2003
- Subjects: Sponges -- South Africa PQQ (Biochemistry) Marine metabolites -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4340 , http://hdl.handle.net/10962/d1005001
- Description: An in depth chemical investigation of the major and minor pyrroloiminoquinone metabolites produced by four species of endemic South African Latrunculid sponges, collected from Algoa Bay and the Tsitsikamma Marine Reserve off the south eastern coast of South Africa, yielded eleven new and twelve known pyrroloiminoquinone metabolites. The structures of the new metabolites were determined using standard spectroscopic techniques. Tsitsikamma pedunculata was shown to contain 7,8-dehydro-3-dihydro-discorhabdin C (2.1), 14-bromo-7,8-dehydro-3-dihydro-discorhabdin C (2.2), discorhabdin S (2.3), 14-bromo-1-hydroxy-discorhabdin S (2.4), 1-bromo-2-hydroxy-4-debromo-discorhabdin S (2.5), and 2,4-debromo-3-dihydro-discorhabdin C (2.6), together with the known compounds 14-bromo-discorhabdin C (1.51), 14-bromo-3-dihydro-discorhabdin C (1.52) and 3-dihydro-discorhabdin C. The metabolites from T. pedunculata were characterised by the presence of a reduced C-3 carbonyl and bromination at C-14. Compounds isolated from a second Latrunculid sponge, Latrunculia lorii, ranged from a substituted bicyclic pyrrolecarboxylic acid, makaluvic acid A (1.47), to the simple tricyclic known pyrroloiminoquinones makaluvamine C (1.33) and damirone B (1.20) and the more complex discorhabdin D type metabolites, discorhabdin M (3.2), 1-amino discorhabdin D (3.3), 1-methoxy discorhabdin D (3.4) and 1-alanyl discorhabdin D (3.5). Discorhabdin G* (3.1) was also isolated and characterised. This is the first reported occurrence of the known compounds 1.20, 1.33 and 1.47 in a Latrunculia sponge. Discorhabdin and bis-pyrroloiminoquinone type compounds predominated in Tsitsikamma favus. Three known, tsitsikammamines A (1.71) and B (1.72), 1.52, and five new pyrroloiminoquinones, tsitsikammamine N-oxime (4.1), tsitsikammamine B N-oxime (4.2), 2.1, 2.4 and 2.6, were isolated from this sponge. A fourth Latrunculid sponge (Strongylodesma sp.) yielded three known compounds, discorhabdins A (1.57), D (1.61) and 1.53, and one new pyrroloiminoquinone 3.3. The dual role of these metabolites as cytotoxic agents and pigments resulted in an attempt to relate the photochemical properties of these metabolites to their cytotoxicity. The pyrroloiminoquinone metabolites studied exhibited moderate singlet oxygen quantum yields, while three compounds (1.57, 4.1 and 4.2) were shown to be capable of producing radicals at a wavelength of 532 nm. The possibility of a correlation between the electrochemical properties and anti-cancer (HCT-116) activity of selected pyrroloiminoquinones was explored. A study of the oesophageal and ovarian cytotoxicities of two pyrroloiminoquinones (1.57 and 1.72), together with an investigation into the intercalation and topoisomerase I inhibitory activity of the bis-pyrroloiminoquinones (1.71, 1.72, 4.1 and 4.2), are presented.
- Full Text:
- Date Issued: 2003
Quality of life and positive youth development in Grahamstown East, South Africa
- Authors: Moller, Valerie
- Date: 2003
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10962/2363 , vital:20281
- Description: Quality-of-life studies are ideally suited to fulfilling the new international youth research agenda, which focuses on ‘positive youth development’ to make recommendations for policy and practice. The paper reports a South African case study conducted among disadvantaged youth for this purpose. A sample survey of close on 900 African youth, aged 15-24 years, sought to identify indicators of positive development to serve as goals of youth and community work in Grahamstown East/Rini, in the Eastern Cape province of South Africa. The setting is unique. This mainly rural province is among the poorest, least developed, and has one of highest unemployment rates. Nevertheless, Grahamstown may offer special development opportunities for local youth due to the proximity of the city centre and diverse extension projects for youth. The survey found that development opportunities were unequally distributed with the materially advantaged youth being more exposed to development opportunities through their schools, spare time activities, and community contacts. They were more ambitious than others and more aware of risks facing contemporary youth. Advantaged youth also reported higher levels of subjective well-being and optimism, findings consistent with earlier studies conducted among adult populations, which report remarkable congruence between material and subjective well-being among South Africans. The analysis used overall life satisfaction as key indicator of successful youth development to learn more about major youth aspirations and goals. In conclusion, the study was able to identify a youth development initiative based on the aspirations of the youth, which might be pursued as a researcher-practitioner partnership project in line with the new international youth research agenda.
- Full Text:
- Date Issued: 2003
- Authors: Moller, Valerie
- Date: 2003
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10962/2363 , vital:20281
- Description: Quality-of-life studies are ideally suited to fulfilling the new international youth research agenda, which focuses on ‘positive youth development’ to make recommendations for policy and practice. The paper reports a South African case study conducted among disadvantaged youth for this purpose. A sample survey of close on 900 African youth, aged 15-24 years, sought to identify indicators of positive development to serve as goals of youth and community work in Grahamstown East/Rini, in the Eastern Cape province of South Africa. The setting is unique. This mainly rural province is among the poorest, least developed, and has one of highest unemployment rates. Nevertheless, Grahamstown may offer special development opportunities for local youth due to the proximity of the city centre and diverse extension projects for youth. The survey found that development opportunities were unequally distributed with the materially advantaged youth being more exposed to development opportunities through their schools, spare time activities, and community contacts. They were more ambitious than others and more aware of risks facing contemporary youth. Advantaged youth also reported higher levels of subjective well-being and optimism, findings consistent with earlier studies conducted among adult populations, which report remarkable congruence between material and subjective well-being among South Africans. The analysis used overall life satisfaction as key indicator of successful youth development to learn more about major youth aspirations and goals. In conclusion, the study was able to identify a youth development initiative based on the aspirations of the youth, which might be pursued as a researcher-practitioner partnership project in line with the new international youth research agenda.
- Full Text:
- Date Issued: 2003
Reader-response approaches to literature teaching in a South African OBE environment
- Authors: Van Renen, Charles Gerard
- Date: 2003
- Subjects: Reader-response criticism -- South Africa , Literature -- Study and teaching -- South Africa , Competency-based education -- South Africa
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11013 , http://hdl.handle.net/10948/297 , Reader-response criticism -- South Africa , Literature -- Study and teaching -- South Africa , Competency-based education -- South Africa
- Description: This research is based on the hypothesis that response-based approaches to teaching literature and an outcomes-based system of education (OBE) are conceptually incompatible. This thesis claims that reader response involves processes that cannot be accommodated pedagogically within a system based on pre-determined outcomes. Furthermore, the kind of assessment prescribed by OBE is inappropriate to the nature of reader response. The hypothesis is based on three main premises. The first is that each reader brings a highly individual and complex set of personal schemata to the reading of imaginative texts, and these schemata have a decisive influence on the nature of a reader’s response. This means that response during imaginative engagements with literary texts tends to be idiosyncratic, and therefore largely unpredictable. Because of this, it would be inappropriate for a teacher, working within an OBE system, to try to teach towards pre-selected outcomes and to attempt to ensure that these outcomes, based on responses to literary texts, are in fact achieved. The second premise is that readers’ imaginative engagements with literary texts are essentially hidden events, which even the individual reader cannot fully bring to the surface and articulate. Because they are complex, and to some extent inaccessible, it would be inappropriate to assess the processes of response in the form of tangible evidence that a particular kind of response has taken place, or an outcome achieved. The third premise is that responses need time to grow and develop and do not merely happen quickly and cleanly. Consequently, aesthetic response, already a complex and inaccessible process, has no clearly distinguishable beginnings or endings. It would therefore be inappropriate to try to pinpoint the exact nature and parameters of a particular response or fragment it into a discrete unit of competence or knowledge. A two-dimensional problem emerges. The first is a conceptual one: whether there is an inherent tension between encouraging response to imaginative literature on the one hand, and accepting the rationale for OBE, on the other. The second dimension of the problem is empirical: whether teachers of literature experience any tension of either a conceptual or a practical nature when following response based approaches within the OBE system of Curriculum 2005, and if so, what they do in order to cope. In exploring the conceptual problem, the argument of this thesis is supported by reception theory and reader response criticism. The former provides key theoretical principles and insights that illuminate the nature of aesthetic reading, while the latter describes and analyses the nature, extent and manifestations of response in educational contexts, underpinned by both reception theory and empirical research. Together they offer evidence that personal response is determined by a complex range of processes, and is the core activity in reading for aesthetic purposes. This thesis also examines the conceptual basis and the structure of OBE as interpreted in both Curriculum 2005 and the revised National Curriculum Statement. The purpose of this is to establish the extent to which the philosophy and modus operandi of these curricula are rooted in notions of competence, and the requirement that learners give tangible demonstrations of pre-determined outcomes being achieved. If it is found that the curricula do lean heavily on pre-determined outcomes in regard to competencies that must be demonstrated, it may be concluded that 1) reader response activities are incompatible with OBE in a South African context, and 2) the potential exists for such incompatibility to create obstacles to creative and effective literature teaching. This can lead to difficulties for the teacher, who will then have to adopt acceptable strategies to cope with the situation. These strategies may ultimately be to the detriment of the pupils, particularly if the teacher seeks a compromise between genuine response and the kinds of activities that would yield precise, palpable measures of attainment that can be easily demonstrated. Exploring the empirical dimension of the problem involves investigating the responses of both teachers and teacher trainers to the experience of promoting response-based literature teaching and learning in an OBE environment. In order firstly investigated whether the practitioners do encourage reading response as a core activity in reading for aesthetic purposes. The extent to which practitioners have a sound grasp of the conceptual issues relevant to this research is also investigated. Insight into such issues depends on teachers and teacher trainers understanding the nature of reader response, on the one hand, and the rationale and structures of the relevant OBE curricula, on the other. Whether, and to what extent, practitioners experience tensions through their awareness of conceptual incompatibilities is also investigated. It should be borne in mind that practitioners work in real contexts in which a variety of complex factors play a role in determining how they respond to pressures from the environment. It cannot therefore be expected that teachers and others involved in delivering the curriculum will be able to reflect on purely conceptual issues without being influenced to an extent by more practical or logistical considerations. However, this study argues that the extent to which they are able to identify the relevant factors that affect the conceptual underpinnings of their practice will determine the degree to which their responses support the argument of this thesis. Together, the empirical and the theoretical findings offer qualitative evidence that should illuminate the nature and extent of the problem.
- Full Text:
- Date Issued: 2003
- Authors: Van Renen, Charles Gerard
- Date: 2003
- Subjects: Reader-response criticism -- South Africa , Literature -- Study and teaching -- South Africa , Competency-based education -- South Africa
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11013 , http://hdl.handle.net/10948/297 , Reader-response criticism -- South Africa , Literature -- Study and teaching -- South Africa , Competency-based education -- South Africa
- Description: This research is based on the hypothesis that response-based approaches to teaching literature and an outcomes-based system of education (OBE) are conceptually incompatible. This thesis claims that reader response involves processes that cannot be accommodated pedagogically within a system based on pre-determined outcomes. Furthermore, the kind of assessment prescribed by OBE is inappropriate to the nature of reader response. The hypothesis is based on three main premises. The first is that each reader brings a highly individual and complex set of personal schemata to the reading of imaginative texts, and these schemata have a decisive influence on the nature of a reader’s response. This means that response during imaginative engagements with literary texts tends to be idiosyncratic, and therefore largely unpredictable. Because of this, it would be inappropriate for a teacher, working within an OBE system, to try to teach towards pre-selected outcomes and to attempt to ensure that these outcomes, based on responses to literary texts, are in fact achieved. The second premise is that readers’ imaginative engagements with literary texts are essentially hidden events, which even the individual reader cannot fully bring to the surface and articulate. Because they are complex, and to some extent inaccessible, it would be inappropriate to assess the processes of response in the form of tangible evidence that a particular kind of response has taken place, or an outcome achieved. The third premise is that responses need time to grow and develop and do not merely happen quickly and cleanly. Consequently, aesthetic response, already a complex and inaccessible process, has no clearly distinguishable beginnings or endings. It would therefore be inappropriate to try to pinpoint the exact nature and parameters of a particular response or fragment it into a discrete unit of competence or knowledge. A two-dimensional problem emerges. The first is a conceptual one: whether there is an inherent tension between encouraging response to imaginative literature on the one hand, and accepting the rationale for OBE, on the other. The second dimension of the problem is empirical: whether teachers of literature experience any tension of either a conceptual or a practical nature when following response based approaches within the OBE system of Curriculum 2005, and if so, what they do in order to cope. In exploring the conceptual problem, the argument of this thesis is supported by reception theory and reader response criticism. The former provides key theoretical principles and insights that illuminate the nature of aesthetic reading, while the latter describes and analyses the nature, extent and manifestations of response in educational contexts, underpinned by both reception theory and empirical research. Together they offer evidence that personal response is determined by a complex range of processes, and is the core activity in reading for aesthetic purposes. This thesis also examines the conceptual basis and the structure of OBE as interpreted in both Curriculum 2005 and the revised National Curriculum Statement. The purpose of this is to establish the extent to which the philosophy and modus operandi of these curricula are rooted in notions of competence, and the requirement that learners give tangible demonstrations of pre-determined outcomes being achieved. If it is found that the curricula do lean heavily on pre-determined outcomes in regard to competencies that must be demonstrated, it may be concluded that 1) reader response activities are incompatible with OBE in a South African context, and 2) the potential exists for such incompatibility to create obstacles to creative and effective literature teaching. This can lead to difficulties for the teacher, who will then have to adopt acceptable strategies to cope with the situation. These strategies may ultimately be to the detriment of the pupils, particularly if the teacher seeks a compromise between genuine response and the kinds of activities that would yield precise, palpable measures of attainment that can be easily demonstrated. Exploring the empirical dimension of the problem involves investigating the responses of both teachers and teacher trainers to the experience of promoting response-based literature teaching and learning in an OBE environment. In order firstly investigated whether the practitioners do encourage reading response as a core activity in reading for aesthetic purposes. The extent to which practitioners have a sound grasp of the conceptual issues relevant to this research is also investigated. Insight into such issues depends on teachers and teacher trainers understanding the nature of reader response, on the one hand, and the rationale and structures of the relevant OBE curricula, on the other. Whether, and to what extent, practitioners experience tensions through their awareness of conceptual incompatibilities is also investigated. It should be borne in mind that practitioners work in real contexts in which a variety of complex factors play a role in determining how they respond to pressures from the environment. It cannot therefore be expected that teachers and others involved in delivering the curriculum will be able to reflect on purely conceptual issues without being influenced to an extent by more practical or logistical considerations. However, this study argues that the extent to which they are able to identify the relevant factors that affect the conceptual underpinnings of their practice will determine the degree to which their responses support the argument of this thesis. Together, the empirical and the theoretical findings offer qualitative evidence that should illuminate the nature and extent of the problem.
- Full Text:
- Date Issued: 2003
Realistic autonomous fish for virtual reality
- Lobb, Adele, Bangay, Shaun D
- Authors: Lobb, Adele , Bangay, Shaun D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433398 , vital:72967 , https://doi.org/10.1145/602330.602361
- Description: We create realistic autonomous fish for Virtual Reality systems. The fish are realistic in appearance, movement and behaviour: the swimming behaviour being non-scripted, within real time rendering.The form of the fish is procedurally created. The size and shape of the form are controlled by a number of variables which are stored in a simple ASCII file. This allows efficient creation of different fish at run time.The behaviour is obtained by implementing a flocking algorithm.
- Full Text:
- Date Issued: 2003
- Authors: Lobb, Adele , Bangay, Shaun D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433398 , vital:72967 , https://doi.org/10.1145/602330.602361
- Description: We create realistic autonomous fish for Virtual Reality systems. The fish are realistic in appearance, movement and behaviour: the swimming behaviour being non-scripted, within real time rendering.The form of the fish is procedurally created. The size and shape of the form are controlled by a number of variables which are stored in a simple ASCII file. This allows efficient creation of different fish at run time.The behaviour is obtained by implementing a flocking algorithm.
- Full Text:
- Date Issued: 2003
Refining lecturers’ assessment practices through formal professional development at Rhodes University, Grahamstown
- Authors: Sayigh, Elizabeth
- Date: 2003
- Language: English
- Type: Conference paper
- Identifier: vital:6080 , http://hdl.handle.net/10962/d1008584
- Description: In recent years, the so-called Accreditation and Registration of Assessors has given rise to much debate in the Higher Education sector. The idea that anyone assessing student learning should be required to train in order to gain a formal qualification and register as an assessor originated with the South African Qualifications Authority (SAQA) and was soon challenged within the higher education community. The Study Team appointed to investigate the implementation of the NQF (National Qualifications Framework) in 2001 recommended that registration of assessors should not be required of individuals teaching in the higher education sector if employed by an accredited institution and this recommendation was later accepted by the Department of Education and the Department of Labour in their joint consultative document entitled ‘An Interdependent National Qualifications Framework System’ (Department of Education, Department of Labour 2003). The waiving of the requirement to register assessors has been welcomed within the public higher education sector. But despite this, the need to train and qualify assessors of students’ learning remains important due to the emphasis placed on assessment by the HEQC (Higher Education Quality Committee) in its ‘Criteria for Institutional Audits’ (2004). The central issue has become how higher education institutions are to successfully train lecturers as assessors in higher education.
- Full Text:
- Date Issued: 2003
- Authors: Sayigh, Elizabeth
- Date: 2003
- Language: English
- Type: Conference paper
- Identifier: vital:6080 , http://hdl.handle.net/10962/d1008584
- Description: In recent years, the so-called Accreditation and Registration of Assessors has given rise to much debate in the Higher Education sector. The idea that anyone assessing student learning should be required to train in order to gain a formal qualification and register as an assessor originated with the South African Qualifications Authority (SAQA) and was soon challenged within the higher education community. The Study Team appointed to investigate the implementation of the NQF (National Qualifications Framework) in 2001 recommended that registration of assessors should not be required of individuals teaching in the higher education sector if employed by an accredited institution and this recommendation was later accepted by the Department of Education and the Department of Labour in their joint consultative document entitled ‘An Interdependent National Qualifications Framework System’ (Department of Education, Department of Labour 2003). The waiving of the requirement to register assessors has been welcomed within the public higher education sector. But despite this, the need to train and qualify assessors of students’ learning remains important due to the emphasis placed on assessment by the HEQC (Higher Education Quality Committee) in its ‘Criteria for Institutional Audits’ (2004). The central issue has become how higher education institutions are to successfully train lecturers as assessors in higher education.
- Full Text:
- Date Issued: 2003
Regionalism and conflict resolution in the Horn of Africa : the role of inter-governmental authority on development in the Sudanese civil war
- Authors: Onyango, Moses
- Date: 2003
- Subjects: Africa, Northeast -- Politics and government -- 1900-1974 , Africa, Northeast -- Politics and government -- 1974- , Africa, Northeast -- Foreign relations -- 1974- , Federal government -- Africa, Northeast , Sudan -- History -- Civil War, 1955-1972 , Mediation, International , Culture conflict Sudan
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2869 , http://hdl.handle.net/10962/d1007715 , Africa, Northeast -- Politics and government -- 1900-1974 , Africa, Northeast -- Politics and government -- 1974- , Africa, Northeast -- Foreign relations -- 1974- , Federal government -- Africa, Northeast , Sudan -- History -- Civil War, 1955-1972 , Mediation, International , Culture conflict Sudan
- Description: This thesis expounds the theoretical underpinnings of problem-solving approach to conflict resolution. It also criticizes the traditional state-centric approach to conflict resolution being followed by the Inter Governmental Authority on Development (IGAD) in the Sudanese civil war. IGAD was initially known as Inter Governmental Authority on Drought and Desertification (IGADD), but was renamed IGAD in 1996. Its objectives were reformulated to give priority to conflict prevention, resolution, and management, and humanitarian affairs. It is stipulated in the thesis that IGAD faces problems that need attention if the Sudanese civil war is to be resolved. A key problem is that while IGAD's objectives were reformulated to give priority to conflict resolution, IGAD's management structure has remained the same. The management structure is state-centric and lacks neutrality, which is a very important ingredient in deep-rooted social conflict resolution. The management structure, which was initially based on combating drought and desertification, was not restructured to conform to the realities of a problem solving approach to conflict resolution. The committee that was formed to look into the Sudanese conflict is composed of states in dispute with Sudan. The other structural problem cited in the thesis is that the IGAD peace process is cumbersome and does not include all aggrieved parties. The meetings involve heads of state, ministers, ambassadors and other government representatives. The peace process is not inclusive of other important players such as other rebel movements. This thesis concludes that: 1. there is a need for peace keeping forces from neutral African Union (AU) member states; 2. conflict resolution specialists are deployed in the region whose main task would be to assist the belligerent groups to reach a common understanding of their problems; 3. the United Nations (UN) acts proactively to create international awareness to the Sudanese problem.
- Full Text:
- Date Issued: 2003
- Authors: Onyango, Moses
- Date: 2003
- Subjects: Africa, Northeast -- Politics and government -- 1900-1974 , Africa, Northeast -- Politics and government -- 1974- , Africa, Northeast -- Foreign relations -- 1974- , Federal government -- Africa, Northeast , Sudan -- History -- Civil War, 1955-1972 , Mediation, International , Culture conflict Sudan
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2869 , http://hdl.handle.net/10962/d1007715 , Africa, Northeast -- Politics and government -- 1900-1974 , Africa, Northeast -- Politics and government -- 1974- , Africa, Northeast -- Foreign relations -- 1974- , Federal government -- Africa, Northeast , Sudan -- History -- Civil War, 1955-1972 , Mediation, International , Culture conflict Sudan
- Description: This thesis expounds the theoretical underpinnings of problem-solving approach to conflict resolution. It also criticizes the traditional state-centric approach to conflict resolution being followed by the Inter Governmental Authority on Development (IGAD) in the Sudanese civil war. IGAD was initially known as Inter Governmental Authority on Drought and Desertification (IGADD), but was renamed IGAD in 1996. Its objectives were reformulated to give priority to conflict prevention, resolution, and management, and humanitarian affairs. It is stipulated in the thesis that IGAD faces problems that need attention if the Sudanese civil war is to be resolved. A key problem is that while IGAD's objectives were reformulated to give priority to conflict resolution, IGAD's management structure has remained the same. The management structure is state-centric and lacks neutrality, which is a very important ingredient in deep-rooted social conflict resolution. The management structure, which was initially based on combating drought and desertification, was not restructured to conform to the realities of a problem solving approach to conflict resolution. The committee that was formed to look into the Sudanese conflict is composed of states in dispute with Sudan. The other structural problem cited in the thesis is that the IGAD peace process is cumbersome and does not include all aggrieved parties. The meetings involve heads of state, ministers, ambassadors and other government representatives. The peace process is not inclusive of other important players such as other rebel movements. This thesis concludes that: 1. there is a need for peace keeping forces from neutral African Union (AU) member states; 2. conflict resolution specialists are deployed in the region whose main task would be to assist the belligerent groups to reach a common understanding of their problems; 3. the United Nations (UN) acts proactively to create international awareness to the Sudanese problem.
- Full Text:
- Date Issued: 2003
Rendering optimisations for stylised sketching
- Winnemöller, Holger, Bangay, Shaun D
- Authors: Winnemöller, Holger , Bangay, Shaun D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432922 , vital:72913 , https://doi.org/10.1145/602330.602353
- Description: We present work that specifically pertains to the rendering stage of stylised, non-photorealistic sketching. While a substantial body of work has been published on geometric optimisations, surface topologies, space-algorithms and natural media simulation, rendering-specific issues are rarely discussed in-depth even though they are often acknowledged. We investigate the most common stylised sketching approaches and identify possible rendering optimisations. In particular, we define uncertainty-functions, which are used to describe a human-error component, discuss how these pertain to geometric perturbation and textured silhouette sketching and explain how they can be cached to improve performance. Temporal coherence, which poses a problem for textured silhouette sketching, is addressed by means of an easily computed visibility-function. Lastly, we produce an effective yet surprisingly simple solution to seamless hatching, which commonly presents a large computational overhead, by using 3-D textures in a novel fashion. All our optimisations are cost-effective, easy to implement and work in conjunction with most existing algorithms.
- Full Text:
- Date Issued: 2003
- Authors: Winnemöller, Holger , Bangay, Shaun D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432922 , vital:72913 , https://doi.org/10.1145/602330.602353
- Description: We present work that specifically pertains to the rendering stage of stylised, non-photorealistic sketching. While a substantial body of work has been published on geometric optimisations, surface topologies, space-algorithms and natural media simulation, rendering-specific issues are rarely discussed in-depth even though they are often acknowledged. We investigate the most common stylised sketching approaches and identify possible rendering optimisations. In particular, we define uncertainty-functions, which are used to describe a human-error component, discuss how these pertain to geometric perturbation and textured silhouette sketching and explain how they can be cached to improve performance. Temporal coherence, which poses a problem for textured silhouette sketching, is addressed by means of an easily computed visibility-function. Lastly, we produce an effective yet surprisingly simple solution to seamless hatching, which commonly presents a large computational overhead, by using 3-D textures in a novel fashion. All our optimisations are cost-effective, easy to implement and work in conjunction with most existing algorithms.
- Full Text:
- Date Issued: 2003
Review and development of environmental interpretation resources to foster environmental learning in two Kenyan schools
- Authors: Atiti, Abel Barasa
- Date: 2003
- Subjects: Environmental education -- Kenya Environmental education -- Kenya -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1743 , http://hdl.handle.net/10962/d1003627
- Description: This participatory action research study involved a group of teachers in transforming school grounds into interpretation resources. Approached from a critical perspective, it challenged the conventional top-down approaches to interpretation resources and materials development. Through a teacher-centred approach, a school-based ‘botanic garden’ and ‘arboretum’ were developed at Samaj and Kenya High respectively. Teachers were further actively engaged in developing a variety of interpretive materials that might engage learners in socially critical environmental education processes at the transformed sites. A process in which educators from five non-formal education organisations shared their skills and knowledge on environmental interpretation with teachers preceded the development of interpretation resources and materials. Drawing on Latour (1999), I have applied the notion of mobilising interpretive capital when describing this process. Interpretive capital within the non-formal education sector was mobilised and made available through social interactions between teachers and non-formal educators. This occurred during workshops, organisational visits and critical reviews of a sample of interpretive materials. I provide insights into how the interpretive capital was mobilised and later drawn on by teachers during the development processes in their schools. This study argues that mobilising interpretive capital with teachers through partnerships can enhance the transformation of school grounds to foster environmental learning. It shows how attempts to find solutions with teachers were made in response to pedagogical and curriculum tensions that arise around the implementation of environmental education processes in their schools. To provide orientation in environmental education processes in schools, analyses of socially critical environmental education processes and a review of theoretical perspectives on interpretation as an environmental education process are presented. I have viewed interpretation and environmental education as reciprocally necessary aspects for enabling the development of critical environmental literacy and action competence. To explain this view, the notion of environmental interpretation and education processes has been applied and presented in this study. Finally, practical outcomes of the study on transformation of school grounds, improved education practice, enhanced professional competencies amongst teachers, new interpretive materials in schools and the establishment of partnerships are examined.
- Full Text:
- Date Issued: 2003
- Authors: Atiti, Abel Barasa
- Date: 2003
- Subjects: Environmental education -- Kenya Environmental education -- Kenya -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1743 , http://hdl.handle.net/10962/d1003627
- Description: This participatory action research study involved a group of teachers in transforming school grounds into interpretation resources. Approached from a critical perspective, it challenged the conventional top-down approaches to interpretation resources and materials development. Through a teacher-centred approach, a school-based ‘botanic garden’ and ‘arboretum’ were developed at Samaj and Kenya High respectively. Teachers were further actively engaged in developing a variety of interpretive materials that might engage learners in socially critical environmental education processes at the transformed sites. A process in which educators from five non-formal education organisations shared their skills and knowledge on environmental interpretation with teachers preceded the development of interpretation resources and materials. Drawing on Latour (1999), I have applied the notion of mobilising interpretive capital when describing this process. Interpretive capital within the non-formal education sector was mobilised and made available through social interactions between teachers and non-formal educators. This occurred during workshops, organisational visits and critical reviews of a sample of interpretive materials. I provide insights into how the interpretive capital was mobilised and later drawn on by teachers during the development processes in their schools. This study argues that mobilising interpretive capital with teachers through partnerships can enhance the transformation of school grounds to foster environmental learning. It shows how attempts to find solutions with teachers were made in response to pedagogical and curriculum tensions that arise around the implementation of environmental education processes in their schools. To provide orientation in environmental education processes in schools, analyses of socially critical environmental education processes and a review of theoretical perspectives on interpretation as an environmental education process are presented. I have viewed interpretation and environmental education as reciprocally necessary aspects for enabling the development of critical environmental literacy and action competence. To explain this view, the notion of environmental interpretation and education processes has been applied and presented in this study. Finally, practical outcomes of the study on transformation of school grounds, improved education practice, enhanced professional competencies amongst teachers, new interpretive materials in schools and the establishment of partnerships are examined.
- Full Text:
- Date Issued: 2003
Review of South African research on volcanic and related rocks and mantle-derived materials : 1999-2002
- Authors: Marsh, Julian S
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6737 , http://hdl.handle.net/10962/d1007550
- Description: This report reviews South African research relating to the scientific interests of the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) and which was published between 1999 and 2002. The focus is on published work and does not include conference presentations and abstract volumes or other informal documents.
- Full Text:
- Date Issued: 2003
- Authors: Marsh, Julian S
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6737 , http://hdl.handle.net/10962/d1007550
- Description: This report reviews South African research relating to the scientific interests of the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) and which was published between 1999 and 2002. The focus is on published work and does not include conference presentations and abstract volumes or other informal documents.
- Full Text:
- Date Issued: 2003
Review of the Cardinalfishes (Perciformes: Apogonidae) of the Red Sea
- Authors: Gon, Ofer , Randall, John E
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:7150 , http://hdl.handle.net/10962/d1011853
- Description: Twelve genera and 54 species of cardinalfishes are reported from the Red Sea. The Red Sea cardinalfishes include: Apogon annularis Rüppell, A. apogonides (Bleeker), Apogon bryx Fraser, A. campbelli Smith, A. coccineus Rüppell, A. cookii Macleay, A. cyanosoma Bleeker, A. erythrosoma n. sp., A. exostigma (Jordan & Starks), A. fleurieu (Lacepède), A. fraenatus Valenciennes, A. guamensis Valenciennes, A. gularis Fraser & Lachner, A. heptastygma Cuvier, A. isus Randall & Böhlke, A. kallopterus Bleeker, A. leptacanthus Bleeker, A. multitaeniatus Cuvier, A. nigrofasciatus Lachner, A. pharaonis Bellotti, A. pselion Randall, Fraser & Lachner, A. pseudotaeniatus Gon, A. quadrifasciatus Cuvier, A. queketti Gilchrist, A. semiornatus Peters, A. smithi (Kotthaus), A. spilurus Regan, A. taeniatus Cuvier, A. talboti Smith, A. timorensis Bleeker, A. zebrinus Fraser, Randall & Lachner, Apogonichthys perdix Bleeker, Archamia bilineata Gon & Randall, Archamia fucata (Cantor), Archamia lineolata (Cuvier), Cercamia eremia (Allen), Cheilodipterus lachneri Klausewitz, C. lineatus (Forsskål), C. macrodon LacepPde, C. novemstriatus (Rüppell), C. pygmaios Gon, C. quinquelineatus Cuvier, Foa fo Jordan & Seale, Fowleria aurita (Valenciennes), F. marmorata (Alleyne & Macleay), F. vaiulae (Jordan & Seale), F. variegata (Valenciennes), Neamia octospina Smith & Radcliffe, Pseudamia gelatinosa Smith, Rhabdamia cypselura Weber, R. nigrimentum (Smith), R. spilota Allen & Kuiter, Siphamia permutata Klausewitz, and Sphaeramia orbicularis (Cuvier). Twelve (22%) of the apogonid species are endemic. Seven species, i.e. Apogon apogonides, A. campbelli, A. erythrosoma, A. talboti, Foa fo, Rhabdamia spilota and Sphaeramia orbicularis, are new to the Red Sea. Apogon coccineus of previous authors is a complex of three species, including campbelli Smith and erythrosoma n. sp. The dark-striped species of Apogon of the Red Sea previously identified as angustatus, endekataenia, fasciatus, or novemfasciatus are cookii and nigrofasciatus. Red Sea apogonids identified by previous authors as Apogon bandanensis, monochrous, nubilus and savayensis, are guamensis and zebrinus. Apogon micromaculatus Kotthaus is A. spilurus Regan. The specimen of Apogon kiensis reported by Smith (1961) from the Red Sea is A. bryx, recently described from the Philippines. In the genus Fowleria, polystigma (Bleeker) and punctulata (Rüppell) are junior synonyms of variegata (Valenciennes). F. abocellata Goren & Karplus is a junior synonym of vaiulae (Jordan & Seale), and isostigma (Jordan & Seale) does not occur in the Red Sea. Apogon cupreus and A. latus, both of Cuvier, are unidentifiable. A. hyalosoma and A. taeniophorus are doubtful records.
- Full Text:
- Date Issued: 2003
- Authors: Gon, Ofer , Randall, John E
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:7150 , http://hdl.handle.net/10962/d1011853
- Description: Twelve genera and 54 species of cardinalfishes are reported from the Red Sea. The Red Sea cardinalfishes include: Apogon annularis Rüppell, A. apogonides (Bleeker), Apogon bryx Fraser, A. campbelli Smith, A. coccineus Rüppell, A. cookii Macleay, A. cyanosoma Bleeker, A. erythrosoma n. sp., A. exostigma (Jordan & Starks), A. fleurieu (Lacepède), A. fraenatus Valenciennes, A. guamensis Valenciennes, A. gularis Fraser & Lachner, A. heptastygma Cuvier, A. isus Randall & Böhlke, A. kallopterus Bleeker, A. leptacanthus Bleeker, A. multitaeniatus Cuvier, A. nigrofasciatus Lachner, A. pharaonis Bellotti, A. pselion Randall, Fraser & Lachner, A. pseudotaeniatus Gon, A. quadrifasciatus Cuvier, A. queketti Gilchrist, A. semiornatus Peters, A. smithi (Kotthaus), A. spilurus Regan, A. taeniatus Cuvier, A. talboti Smith, A. timorensis Bleeker, A. zebrinus Fraser, Randall & Lachner, Apogonichthys perdix Bleeker, Archamia bilineata Gon & Randall, Archamia fucata (Cantor), Archamia lineolata (Cuvier), Cercamia eremia (Allen), Cheilodipterus lachneri Klausewitz, C. lineatus (Forsskål), C. macrodon LacepPde, C. novemstriatus (Rüppell), C. pygmaios Gon, C. quinquelineatus Cuvier, Foa fo Jordan & Seale, Fowleria aurita (Valenciennes), F. marmorata (Alleyne & Macleay), F. vaiulae (Jordan & Seale), F. variegata (Valenciennes), Neamia octospina Smith & Radcliffe, Pseudamia gelatinosa Smith, Rhabdamia cypselura Weber, R. nigrimentum (Smith), R. spilota Allen & Kuiter, Siphamia permutata Klausewitz, and Sphaeramia orbicularis (Cuvier). Twelve (22%) of the apogonid species are endemic. Seven species, i.e. Apogon apogonides, A. campbelli, A. erythrosoma, A. talboti, Foa fo, Rhabdamia spilota and Sphaeramia orbicularis, are new to the Red Sea. Apogon coccineus of previous authors is a complex of three species, including campbelli Smith and erythrosoma n. sp. The dark-striped species of Apogon of the Red Sea previously identified as angustatus, endekataenia, fasciatus, or novemfasciatus are cookii and nigrofasciatus. Red Sea apogonids identified by previous authors as Apogon bandanensis, monochrous, nubilus and savayensis, are guamensis and zebrinus. Apogon micromaculatus Kotthaus is A. spilurus Regan. The specimen of Apogon kiensis reported by Smith (1961) from the Red Sea is A. bryx, recently described from the Philippines. In the genus Fowleria, polystigma (Bleeker) and punctulata (Rüppell) are junior synonyms of variegata (Valenciennes). F. abocellata Goren & Karplus is a junior synonym of vaiulae (Jordan & Seale), and isostigma (Jordan & Seale) does not occur in the Red Sea. Apogon cupreus and A. latus, both of Cuvier, are unidentifiable. A. hyalosoma and A. taeniophorus are doubtful records.
- Full Text:
- Date Issued: 2003
Revised Schools and Sustainability Pack offers Curriculum Support
- Authors: Olvitt, Lausanne L
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/389852 , vital:68489 , xlink:href="https://eeasa.org.za/wp-content/uploads/2016/12/Bulletin_vol24-_March-2003.pdf"
- Description: Since the mid 1990s, the School Environmental Policy and Management Plan (SEP) Pack has supported educators in developing a whole-school environmental policy. This year, Share-Net has updated the pack in line with the South African revised National Curriculum and the National Environmental Education Programme (NEEP).
- Full Text:
- Date Issued: 2003
- Authors: Olvitt, Lausanne L
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/389852 , vital:68489 , xlink:href="https://eeasa.org.za/wp-content/uploads/2016/12/Bulletin_vol24-_March-2003.pdf"
- Description: Since the mid 1990s, the School Environmental Policy and Management Plan (SEP) Pack has supported educators in developing a whole-school environmental policy. This year, Share-Net has updated the pack in line with the South African revised National Curriculum and the National Environmental Education Programme (NEEP).
- Full Text:
- Date Issued: 2003
Revision of the genus Xiphoscelis Burmeister 1842 (Coleoptera Scarabaeidae Cetoniinae), with description of two new species and notes on its phylogeny and ecology
- Perissinotto, Renzo, Villet, Martin H, Stobbia, P
- Authors: Perissinotto, Renzo , Villet, Martin H , Stobbia, P
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442293 , vital:73973 , https://doi.org/10.1080/03946975.2003.10531184
- Description: Recent field work has shown that the genus Xiphoscelis Burmeister 1842 contains at least three species. The type species is re-described, and two new species are described, based on adult morphology. The distribution of all three Xiphoscelis species is mapped, and a phylogeny is proposed for the genus. Ecological data are presented and discussed in the context of the previously-reported association of members of this genus with termites.
- Full Text:
- Date Issued: 2003
- Authors: Perissinotto, Renzo , Villet, Martin H , Stobbia, P
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442293 , vital:73973 , https://doi.org/10.1080/03946975.2003.10531184
- Description: Recent field work has shown that the genus Xiphoscelis Burmeister 1842 contains at least three species. The type species is re-described, and two new species are described, based on adult morphology. The distribution of all three Xiphoscelis species is mapped, and a phylogeny is proposed for the genus. Ecological data are presented and discussed in the context of the previously-reported association of members of this genus with termites.
- Full Text:
- Date Issued: 2003
Rhodes University Graduation Ceremony 2003
- Authors: Rhodes University
- Date: 2003
- Language: English
- Type: text
- Identifier: vital:8144 , http://hdl.handle.net/10962/d1007264
- Description: Rhodes University Graduation Ceremonies [at] 1820 Settlers National Monument Friday, 11 April 2003 at 10:30; 14:30 & 18:00 [and] Saturday, 12 April at 10:30 , Graduation Ceremony Christian Centre, Wyse Street, East London Friday, 9 May 2003 at 18:00 [and] Saturday, 10 May 2003 at 10:30
- Full Text:
- Date Issued: 2003
- Authors: Rhodes University
- Date: 2003
- Language: English
- Type: text
- Identifier: vital:8144 , http://hdl.handle.net/10962/d1007264
- Description: Rhodes University Graduation Ceremonies [at] 1820 Settlers National Monument Friday, 11 April 2003 at 10:30; 14:30 & 18:00 [and] Saturday, 12 April at 10:30 , Graduation Ceremony Christian Centre, Wyse Street, East London Friday, 9 May 2003 at 18:00 [and] Saturday, 10 May 2003 at 10:30
- Full Text:
- Date Issued: 2003
Rhodes University Research Report 2003
- Authors: Rhodes University
- Date: 2003
- Language: English
- Type: Text
- Identifier: vital:558 , http://hdl.handle.net/10962/d1011947
- Description: [From Preface and Introduction] The core business of a university is teaching and research and Rhodes has excelled in both. Our success in research is also exemplified by the graduation in April of 39 PhD and 111 Masters students. Postgraduate throughput together with research outputs will play a crucial role in the new funding formula for determining Government subsidy to Institutions. In assessing the research output of universities it is important, for comparative purposes, that this is done in relation to the size of an institution. Currently this research output, per size or per capita, is calculated by dividing the research publication output by either the audited FTE’s (i.e. number of students) or the state subsidy, which is largely based on the size of the university. These calculations show that Rhodes has had the best research output per capita for the previous four years. I would like to congratulate the members of staff and postgraduates, particularly in those Departments that are consistently increasing or maintaining their research output, for their contribution to the research effort of the university. I am aware that the research contributions mentioned in this report have been made amidst many demands such as increased student numbers and a very competitive funding environment, to name a few. Asa result of positive feedback received this year we have maintained the layout and format of the first formal research report published in 2002 Please note that each Department’s/Faculty’s highlights section are as provided by the Head of Department as are the research outputs produced. The table of provisional subsidy units earned by each Department/Faculty have been included as there is often a misconception that one journal article equates to one subsidy unit. This is the case if all the authors are from Rhodes University but where articles are jointly published, a pro-rata share is calculated. Likewise due to the complex funding formula used by the Department of Education, the total research outputs produced do not equate directly to the subsidisable units. Please note that "in press" articles in 2002 but published in 2003 have already been claimed in 2002 and hence do not appear in the table but are recorded in the report. Articles that have been submitted for possible publication have not been included in the table nor the report as it is not possible to prove if the articles had been accepted for publication by the time our submission to the Department of Education was audited. Also please note that subsidy units earned for book/chapter/patent/conference proceedings publications are not included in the subsidy unit tables since we receive no feedback from the Department of Education in terms of which books/chapters/patents/proceedings are finally accepted for subsidy purposes each year. Only a small fraction of such books, chapters, patents and proceedings which are submitted actually receive subsidy. I would like to stress the need to publish in subsidy earning journals and to submit accurate information so that the University can claim as many units as possible. The total audited (but not yet awarded) publication subsidy units for journal articles which have been submitted to the Department of Education for 2003 is 180.56 units. This is some 26.08 units down on our 2002 submission and is of concern. Of this figure, publications in current non-subsidy earning journals in 2003 amounted to 5.5 units. These have been forwarded to the Department of Education for consideration for subsidy purposes. Despite the decrease in publication outputs in 2003, postgraduate student graduation, particularly PhD’s, was encouragingly high in 2003 and in general it was once again a highly successful year for research at Rhodes. I would therefore like to add my congratulations to that of the Vice-Chancellor to all staff and postgraduate students for their research efforts in 2003.
- Full Text:
- Date Issued: 2003
- Authors: Rhodes University
- Date: 2003
- Language: English
- Type: Text
- Identifier: vital:558 , http://hdl.handle.net/10962/d1011947
- Description: [From Preface and Introduction] The core business of a university is teaching and research and Rhodes has excelled in both. Our success in research is also exemplified by the graduation in April of 39 PhD and 111 Masters students. Postgraduate throughput together with research outputs will play a crucial role in the new funding formula for determining Government subsidy to Institutions. In assessing the research output of universities it is important, for comparative purposes, that this is done in relation to the size of an institution. Currently this research output, per size or per capita, is calculated by dividing the research publication output by either the audited FTE’s (i.e. number of students) or the state subsidy, which is largely based on the size of the university. These calculations show that Rhodes has had the best research output per capita for the previous four years. I would like to congratulate the members of staff and postgraduates, particularly in those Departments that are consistently increasing or maintaining their research output, for their contribution to the research effort of the university. I am aware that the research contributions mentioned in this report have been made amidst many demands such as increased student numbers and a very competitive funding environment, to name a few. Asa result of positive feedback received this year we have maintained the layout and format of the first formal research report published in 2002 Please note that each Department’s/Faculty’s highlights section are as provided by the Head of Department as are the research outputs produced. The table of provisional subsidy units earned by each Department/Faculty have been included as there is often a misconception that one journal article equates to one subsidy unit. This is the case if all the authors are from Rhodes University but where articles are jointly published, a pro-rata share is calculated. Likewise due to the complex funding formula used by the Department of Education, the total research outputs produced do not equate directly to the subsidisable units. Please note that "in press" articles in 2002 but published in 2003 have already been claimed in 2002 and hence do not appear in the table but are recorded in the report. Articles that have been submitted for possible publication have not been included in the table nor the report as it is not possible to prove if the articles had been accepted for publication by the time our submission to the Department of Education was audited. Also please note that subsidy units earned for book/chapter/patent/conference proceedings publications are not included in the subsidy unit tables since we receive no feedback from the Department of Education in terms of which books/chapters/patents/proceedings are finally accepted for subsidy purposes each year. Only a small fraction of such books, chapters, patents and proceedings which are submitted actually receive subsidy. I would like to stress the need to publish in subsidy earning journals and to submit accurate information so that the University can claim as many units as possible. The total audited (but not yet awarded) publication subsidy units for journal articles which have been submitted to the Department of Education for 2003 is 180.56 units. This is some 26.08 units down on our 2002 submission and is of concern. Of this figure, publications in current non-subsidy earning journals in 2003 amounted to 5.5 units. These have been forwarded to the Department of Education for consideration for subsidy purposes. Despite the decrease in publication outputs in 2003, postgraduate student graduation, particularly PhD’s, was encouragingly high in 2003 and in general it was once again a highly successful year for research at Rhodes. I would therefore like to add my congratulations to that of the Vice-Chancellor to all staff and postgraduate students for their research efforts in 2003.
- Full Text:
- Date Issued: 2003