Synthesis, photophysical and photochemical properties of aryloxy tetra-substituted gallium and indium phthalocyanine derivatives
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281431 , vital:55724 , xlink:href="https://doi.org/10.1016/j.tet.2006.11.089"
- Description: The synthesis, photophysical and photochemical properties of the tetra-substituted aryloxy gallium(III) and indium(III) phthalocyanines are reported for the first time. General trends are described for photodegradation, singlet oxygen, fluorescence, and triplet quantum yields and triplet lifetimes of these compounds. The introduction of phenoxy and tert-butylphenoxy substituents on the ring resulted in lowering of fluorescence quantum yields and lifetimes, and triplet quantum yields, and an increase of kIC, kISC, and kF. Photoreduction of the complexes was observed during laser flash photolysis. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.41 to 0.91. Thus, these complexes show potential as Type II photosensitizers.
- Full Text:
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281431 , vital:55724 , xlink:href="https://doi.org/10.1016/j.tet.2006.11.089"
- Description: The synthesis, photophysical and photochemical properties of the tetra-substituted aryloxy gallium(III) and indium(III) phthalocyanines are reported for the first time. General trends are described for photodegradation, singlet oxygen, fluorescence, and triplet quantum yields and triplet lifetimes of these compounds. The introduction of phenoxy and tert-butylphenoxy substituents on the ring resulted in lowering of fluorescence quantum yields and lifetimes, and triplet quantum yields, and an increase of kIC, kISC, and kF. Photoreduction of the complexes was observed during laser flash photolysis. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.41 to 0.91. Thus, these complexes show potential as Type II photosensitizers.
- Full Text:
Synthesis, Photophysical and Photochemical Properties of Poly (oxyethylene)‐Substituted Phthalocyaninato Oxotitanium (IV) Complexes
- Atilla, Devrim, Durmus, Mahmut, Yılmaz, Özgür, Gürek, Ayşe Gül, Ahsen, Vefa, Nyokong, Tebello
- Authors: Atilla, Devrim , Durmus, Mahmut , Yılmaz, Özgür , Gürek, Ayşe Gül , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271263 , vital:54526 , xlink:href="https://doi.org/10.1002/ejic.200700057"
- Description: The synthesis, photophysical and photochemical properties of tetra- and chlorotetrapoly(oxyethylene)-substituted oxotitanium(IV) phthalocyanines are reported for the first time. The new compounds were characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. These complexes showed monomeric behaviour in solution. General trends are described for photodegredation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethyl sulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The complexes showed high triplet quantum yields and triplet lifetimes in DMSO. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism), were 0.72 and 0.78 for 3a and 5a, respectively. Thus, these complexes show potential as Type II photosensitizers. These complexes were also quenched by benzoquinone for fluorescence quenching studies.
- Full Text:
- Authors: Atilla, Devrim , Durmus, Mahmut , Yılmaz, Özgür , Gürek, Ayşe Gül , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271263 , vital:54526 , xlink:href="https://doi.org/10.1002/ejic.200700057"
- Description: The synthesis, photophysical and photochemical properties of tetra- and chlorotetrapoly(oxyethylene)-substituted oxotitanium(IV) phthalocyanines are reported for the first time. The new compounds were characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. These complexes showed monomeric behaviour in solution. General trends are described for photodegredation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethyl sulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The complexes showed high triplet quantum yields and triplet lifetimes in DMSO. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism), were 0.72 and 0.78 for 3a and 5a, respectively. Thus, these complexes show potential as Type II photosensitizers. These complexes were also quenched by benzoquinone for fluorescence quenching studies.
- Full Text:
Synthesis, photophysical and photochemical properties of tetra-and octa-substituted gallium and indium phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271276 , vital:54529 , xlink:href="https://doi.org/10.1016/j.poly.2007.03.007"
- Description: The synthesis, photophysical and photochemical properties of the tetra- and octa-[4-(benzyloxyphenoxy)] substituted gallium(III) and indium(III) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. General trends are described for quantum yields of photodegredation, fluorescence quantum yields and lifetimes, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds in dimethylsulfoxide (DMSO). Substituted indium phthalocyanine complexes (7b–9b) showed much higher quantum yields of triplet state and shorter triplet lifetimes, compared to the substituted GaPc derivatives due to enhanced intersystem crossing (ISC) in the former. The gallium and indium phthalocyanine complexes showed phototransformation during laser irradiation due to ring reduction. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.51 to 0.94. Thus, these complexes show potential as photodynamic therapy of cancer.
- Full Text:
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271276 , vital:54529 , xlink:href="https://doi.org/10.1016/j.poly.2007.03.007"
- Description: The synthesis, photophysical and photochemical properties of the tetra- and octa-[4-(benzyloxyphenoxy)] substituted gallium(III) and indium(III) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. General trends are described for quantum yields of photodegredation, fluorescence quantum yields and lifetimes, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds in dimethylsulfoxide (DMSO). Substituted indium phthalocyanine complexes (7b–9b) showed much higher quantum yields of triplet state and shorter triplet lifetimes, compared to the substituted GaPc derivatives due to enhanced intersystem crossing (ISC) in the former. The gallium and indium phthalocyanine complexes showed phototransformation during laser irradiation due to ring reduction. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.51 to 0.94. Thus, these complexes show potential as photodynamic therapy of cancer.
- Full Text:
Synthesis, photophysical and photochemical studies of new water-soluble indium (III) phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283976 , vital:56007 , xlink:href="https://doi.org/10.1039/b618478b"
- Description: The preparation of water-soluble indium(III)phthalocyanine complexes is described for the first time in this study. Peripherally and non-peripherally 3-hydroxypyridine tetrasubstituted indium(III) phthalocyanines (5a, 6a) and their quaternarized derivatives (5b, 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b, 6b) show excellent solubility in water, which makes them potential photosensitizers for use in photodynamic therapy (PDT) applications. Photochemical and photophysical measurements were conducted on 3-pyridyloxy appended indium(III) phthalocyanines in dimethylsulfoxide (DMSO) for non-ionic (5b, 6b) derivatives. General trends are described for quantum yields of photodegradation, fluorescence lifetimes, fluorescence quantum yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) are very high (ΦΔ > 0.55). Thus, these complexes may be useful as Type II photosensitizers.
- Full Text:
Synthesis, photophysical and photochemical studies of new water-soluble indium (III) phthalocyanines
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283976 , vital:56007 , xlink:href="https://doi.org/10.1039/b618478b"
- Description: The preparation of water-soluble indium(III)phthalocyanine complexes is described for the first time in this study. Peripherally and non-peripherally 3-hydroxypyridine tetrasubstituted indium(III) phthalocyanines (5a, 6a) and their quaternarized derivatives (5b, 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b, 6b) show excellent solubility in water, which makes them potential photosensitizers for use in photodynamic therapy (PDT) applications. Photochemical and photophysical measurements were conducted on 3-pyridyloxy appended indium(III) phthalocyanines in dimethylsulfoxide (DMSO) for non-ionic (5b, 6b) derivatives. General trends are described for quantum yields of photodegradation, fluorescence lifetimes, fluorescence quantum yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) are very high (ΦΔ > 0.55). Thus, these complexes may be useful as Type II photosensitizers.
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Teacher motivation in a South African school
- Authors: Kovach, John C
- Date: 2007
- Subjects: Teacher morale -- South Africa -- Eastern Cape Teachers -- Professional ethics -- South Africa -- Eastern Cape Teacher-administrator relationships -- South Africa -- Eastern Cape Educational leadership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1790 , http://hdl.handle.net/10962/d1003675
- Description: This study explores and attempts to shed light on what motivates teachers and how teacher motivation is affected by a principal's leadership style. The worldviews of pragmatism and critical realism were used as the basis for exploring teacher motivation in a South African school. A primary school in the Eastern Cape of South Africa was chosen for the case study. Three data gathering tools, a leadership questionnaire, teacher survey, and interviews were used to generate data on teacher motivation and the interaction between leadership style and teacher motivation. In regards to teachers, religion, social justice, and self-efficacy were all identified as motivators. The principal was strongly charismatic in her leadership and along with transformational and social justice leadership played a major role in influencing teacher behaviors. Self-determination theory was identified as helping to explain different levels of intrinsic and extrinsic motivation and thereby to better understand varying degrees of teacher motivation. There are many difficulties in South African education and around the world in general and this study is premised on the belief that if teacher motivation can be studied and advanced there will be an improvement in education and learning. This thesis was limited in its scope and ability to fully explore the different levels of ontology as outlined by the critical realist and this is identified as a possible future course of action for not only studying teacher motivation but getting to the 'heart of the matter'.
- Full Text:
- Authors: Kovach, John C
- Date: 2007
- Subjects: Teacher morale -- South Africa -- Eastern Cape Teachers -- Professional ethics -- South Africa -- Eastern Cape Teacher-administrator relationships -- South Africa -- Eastern Cape Educational leadership -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1790 , http://hdl.handle.net/10962/d1003675
- Description: This study explores and attempts to shed light on what motivates teachers and how teacher motivation is affected by a principal's leadership style. The worldviews of pragmatism and critical realism were used as the basis for exploring teacher motivation in a South African school. A primary school in the Eastern Cape of South Africa was chosen for the case study. Three data gathering tools, a leadership questionnaire, teacher survey, and interviews were used to generate data on teacher motivation and the interaction between leadership style and teacher motivation. In regards to teachers, religion, social justice, and self-efficacy were all identified as motivators. The principal was strongly charismatic in her leadership and along with transformational and social justice leadership played a major role in influencing teacher behaviors. Self-determination theory was identified as helping to explain different levels of intrinsic and extrinsic motivation and thereby to better understand varying degrees of teacher motivation. There are many difficulties in South African education and around the world in general and this study is premised on the belief that if teacher motivation can be studied and advanced there will be an improvement in education and learning. This thesis was limited in its scope and ability to fully explore the different levels of ontology as outlined by the critical realist and this is identified as a possible future course of action for not only studying teacher motivation but getting to the 'heart of the matter'.
- Full Text:
Temple Xingkang
- Authors: Berold, Robert
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , poem
- Identifier: http://hdl.handle.net/10962/462355 , vital:76295 , ISBN 0028-4459 , https://journals.co.za/doi/epdf/10.10520/EJC47794
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Authors: Berold, Robert
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , poem
- Identifier: http://hdl.handle.net/10962/462355 , vital:76295 , ISBN 0028-4459 , https://journals.co.za/doi/epdf/10.10520/EJC47794
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
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The artistic path to virtue
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
- Full Text:
- Authors: Sher, Gavin
- Date: 2007
- Subjects: Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2732 , http://hdl.handle.net/10962/d1004370 , Aristotle -- Nicomachean ethics , Virtue , Ethics , Fiction , Narration (Rhetoric)
- Description: Most people share a strong intuition that there is much to be learned from great literature and other forms of narrative art. This intuition is, however, philosophically contentious. Plato was the first to argue against the possibility of learning anything from narrative art, but he founded a tradition that persists to the present day. I will engage in this debate in order to examine the role narratives might be able to play in acquiring virtue on Aristotle's ethical account, as it is presented in Nicomachean Ethics. I will claim that narratives have so long seemed a problematic source of learning because philosophers have traditionally approached the issue in the wrong way. They have typically tried to show how we might acquire propositional knowledge through our engagement with art, but this approach has failed because of insoluble problems involved in satisfying the justification criterion. Fictions may be rescued from their problematic status by realising that what we truly get from them is, instead, a type of knowledge-how. I will argue that Aristotelian virtue is itself a kind of knowledge-how and so the type of learning that takes place in engaging with narratives has a role to play in its acquisition and exercise. Virtue depends on types of reasoning that are themselves kinds of knowledge-how and which are employed and improved in engaging with narrative art. These types of reasoning will be described as conceptual, emotional and imaginative understanding. I will show how each is important in relation to virtue and how each is a kind of knowledge-how that may be improved through exposure to narrative art.
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The battle for Cassinga : conflicting narratives and contested meanings
- Authors: Baines, Gary F
- Date: 2007
- Language: English
- Type: Conference paper
- Identifier: vital:6156 , http://hdl.handle.net/10962/d1007073
- Description: Nearly thirty years ago the name Cassinga (or Kassinga) came to the attention of the world. At the time the name evoked a range of responses, from outrage to grief to the celebration of military bravado. It still does so. And Cassinga will continue to elicit such responses as long as participants and witnesses are alive and the events remain part of living memory. Obviously perpetrators and survivors remember the events of 4 May 1978 differently. Memory is, after all, selective. The recollections of participants and witnesses are framed by personal and political agendas. This much is abundantly clear from the conflicting accounts of Cassinga that appear in the media and literature, especially the exchanges that take place between parties with a stake in how the events are remembered. Thus a report headlined “Battle of Cassinga still rages” published on the 29th anniversary suggested that the events are still shrouded in controversy and that there is no agreement about what transpired in the southern Angolan town. The title of this paper reflects my concern with the battle for rather than of Cassinga. The choice of preposition is intended to signify the ongoing contestation over the meaning of Cassinga.
- Full Text:
- Authors: Baines, Gary F
- Date: 2007
- Language: English
- Type: Conference paper
- Identifier: vital:6156 , http://hdl.handle.net/10962/d1007073
- Description: Nearly thirty years ago the name Cassinga (or Kassinga) came to the attention of the world. At the time the name evoked a range of responses, from outrage to grief to the celebration of military bravado. It still does so. And Cassinga will continue to elicit such responses as long as participants and witnesses are alive and the events remain part of living memory. Obviously perpetrators and survivors remember the events of 4 May 1978 differently. Memory is, after all, selective. The recollections of participants and witnesses are framed by personal and political agendas. This much is abundantly clear from the conflicting accounts of Cassinga that appear in the media and literature, especially the exchanges that take place between parties with a stake in how the events are remembered. Thus a report headlined “Battle of Cassinga still rages” published on the 29th anniversary suggested that the events are still shrouded in controversy and that there is no agreement about what transpired in the southern Angolan town. The title of this paper reflects my concern with the battle for rather than of Cassinga. The choice of preposition is intended to signify the ongoing contestation over the meaning of Cassinga.
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The biology and laboratory host range of the weevil, Listronotus marginicollis (Hustache)(Coleoptera: Curculionidae), a natural enemy of the invasive aquatic weed, parrot's feather, Myriophyllum aquaticum (Velloso) Verde (Haloragaceae).
- Oberholzer, I G, Mafokoane, D L, Hill, Martin P
- Authors: Oberholzer, I G , Mafokoane, D L , Hill, Martin P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451555 , vital:75059 , https://hdl.handle.net/10520/EJC32727
- Description: Myriophyllum aquaticum (Velloso) Verde (Haloragaceae), parrot's feather, is a rooted aquatic plant, with stems of up to 3 m long and leafy terminal shoots. The plant roots in shallow water to form a dense tangle of stems and roots. The shoots emerge 200-500 mm above the water surface (Cilliers 1999). The leaves of the plant are feathery and occur in whorls. The stem-boring weevil, Listronotus marginicollis (Hustache) (Coleoptera: Curculionidae), was next considered as the most promising additional biological control agent for the control of M. aquaticum in southern Africa (Cilliers 1999).
- Full Text:
- Authors: Oberholzer, I G , Mafokoane, D L , Hill, Martin P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451555 , vital:75059 , https://hdl.handle.net/10520/EJC32727
- Description: Myriophyllum aquaticum (Velloso) Verde (Haloragaceae), parrot's feather, is a rooted aquatic plant, with stems of up to 3 m long and leafy terminal shoots. The plant roots in shallow water to form a dense tangle of stems and roots. The shoots emerge 200-500 mm above the water surface (Cilliers 1999). The leaves of the plant are feathery and occur in whorls. The stem-boring weevil, Listronotus marginicollis (Hustache) (Coleoptera: Curculionidae), was next considered as the most promising additional biological control agent for the control of M. aquaticum in southern Africa (Cilliers 1999).
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The biology and systematics of South African pipefishes of the genus Syngnathus
- Authors: Mwale, Monica
- Date: 2007
- Subjects: Pipefishes -- South Africa Syngnathus -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5237 , http://hdl.handle.net/10962/d1005080
- Description: Syngnathus the most speciose genus in the family Syngnathidae is widely in the Atlantic and Eastern Pacific oceans. However, it is poorly represented in the Indian Ocean with the only two species, Syngnathus temminckii and S. watermeyeri occurring in Southern African estuaries and coastal areas. Syngnathus temminckii the most common South African pipefish has been synonymised with S. acus, as the morphological and genetic divergence between these two populations has not been documented. There is also uncertainty in the taxonomic status of S. watermeyeri, an endemic estuarine pipefish that is restricted to two Eastern Cape estuaries. The purpose of this study was therefore to compare biological, morphological and genetic variation of South African Syngnathus species among different populations/locations, and with European populations of S. acus. Sixteen meristic and ten morphometric characteristics were quantified from specimens obtained from field as well as various international natural history museum collections. Univariate (ANOVA) and multivariate (principal component analysis and discriminant analyses) analyses were used to assess morphological differences among the species. Morphometric variables were adjusted as ratios of the standard length and using an allometric procedure. ANCOVA analysis indicated significant differences between S. acus and S. temminckii for the relationships of the standard length (SL) and all morphological characters. There was no significant correlation between SL and snout length, snout depth, inter-orbital width and trunk depth for S. watermeyeri. The analyses provided evidence for distinct populations of S. acus, S. temminckii and S. watermeyeri although morphological character differentiation was greater between S. watermeyeri and the other two larger species. Although, significant differences were observed for meristic characters, pairwise comparisons did not reflect a clear pattern of variability. Most of the measured morphological characters contributed more than 70% to the morphological variation between the populations. Plot of the canonical scores for the variables resulted in the specimens clustering according to species groups and locations of S. temminckii. Sequences of 750 base pairs of the mitochondrial cytochrome gene from 11 localities were compared with published sequences of other species of Syngnathus. Phylogenetic analysis was performed using parsimony, maximum likelihood (ML) and Bayesian inference (BI). The South African species were revealed to be sister-taxa with about 6 % divergence, while S. temminckii and S. acus had about 11% sequence divergence. 20 haplotypes among 46 total specimens from the three species. Gene flow was estimated at approximately 3 migrants per generation between the two South African populations and about 1 per generation between S. temminckii and S. acus. Such strong stock structuring among presumably recently established post-Pliocene (< 2 Million years ago) populations suggests that these species are reproductively isolated. Morphological and genetic variation observed in this study combined with current knowledge of life history attributes of the South African pipefishes indicate that conservative management decisions are necessary until the patterns and extent of differentiation among populations species-wide can be investigated further. It is thus being proposed that the name of the South African population of S. acus be changed to Syngnathus temminckii (Kaup, 1856).
- Full Text:
- Authors: Mwale, Monica
- Date: 2007
- Subjects: Pipefishes -- South Africa Syngnathus -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5237 , http://hdl.handle.net/10962/d1005080
- Description: Syngnathus the most speciose genus in the family Syngnathidae is widely in the Atlantic and Eastern Pacific oceans. However, it is poorly represented in the Indian Ocean with the only two species, Syngnathus temminckii and S. watermeyeri occurring in Southern African estuaries and coastal areas. Syngnathus temminckii the most common South African pipefish has been synonymised with S. acus, as the morphological and genetic divergence between these two populations has not been documented. There is also uncertainty in the taxonomic status of S. watermeyeri, an endemic estuarine pipefish that is restricted to two Eastern Cape estuaries. The purpose of this study was therefore to compare biological, morphological and genetic variation of South African Syngnathus species among different populations/locations, and with European populations of S. acus. Sixteen meristic and ten morphometric characteristics were quantified from specimens obtained from field as well as various international natural history museum collections. Univariate (ANOVA) and multivariate (principal component analysis and discriminant analyses) analyses were used to assess morphological differences among the species. Morphometric variables were adjusted as ratios of the standard length and using an allometric procedure. ANCOVA analysis indicated significant differences between S. acus and S. temminckii for the relationships of the standard length (SL) and all morphological characters. There was no significant correlation between SL and snout length, snout depth, inter-orbital width and trunk depth for S. watermeyeri. The analyses provided evidence for distinct populations of S. acus, S. temminckii and S. watermeyeri although morphological character differentiation was greater between S. watermeyeri and the other two larger species. Although, significant differences were observed for meristic characters, pairwise comparisons did not reflect a clear pattern of variability. Most of the measured morphological characters contributed more than 70% to the morphological variation between the populations. Plot of the canonical scores for the variables resulted in the specimens clustering according to species groups and locations of S. temminckii. Sequences of 750 base pairs of the mitochondrial cytochrome gene from 11 localities were compared with published sequences of other species of Syngnathus. Phylogenetic analysis was performed using parsimony, maximum likelihood (ML) and Bayesian inference (BI). The South African species were revealed to be sister-taxa with about 6 % divergence, while S. temminckii and S. acus had about 11% sequence divergence. 20 haplotypes among 46 total specimens from the three species. Gene flow was estimated at approximately 3 migrants per generation between the two South African populations and about 1 per generation between S. temminckii and S. acus. Such strong stock structuring among presumably recently established post-Pliocene (< 2 Million years ago) populations suggests that these species are reproductively isolated. Morphological and genetic variation observed in this study combined with current knowledge of life history attributes of the South African pipefishes indicate that conservative management decisions are necessary until the patterns and extent of differentiation among populations species-wide can be investigated further. It is thus being proposed that the name of the South African population of S. acus be changed to Syngnathus temminckii (Kaup, 1856).
- Full Text:
The body as a site of struggle: Oppositional discourses of the disciplined female body
- Pienaar, Kiran M, Bekker, Ian
- Authors: Pienaar, Kiran M , Bekker, Ian
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469223 , vital:77221 , https://doi.org/10.2989/16073610709486480
- Description: This article presents the results of a study on the discursive construction of one aspect of gender identity, namely the female physical ideal. It reports on an analysis of the discourses of the disciplined female body, as these are drawn upon in two conversations between a group of young, Western female university students. The conversations were elicited in August 2005 using a stimulus exercise designed to encourage discussion on issues relating to female body image, such as the notion of the ideal female body, dieting and plastic surgery. Using the tools of Critical Discourse Analysis (CDA) (Fairclough, 2001) the article analyses four related discourses, namely the pro-diet discourse, the discourse of the healthy body, the discourse of studied indifference and the discourse of the sexually attractive female body, in terms of how these discourses encode different, sometimes contradictory ideologies of the Western female body ideal. The article concludes that the discourse of the sexually attractive female body emerges as dominant in these conversational extracts and that, by colonising the other discourses, it legitimates its ethic of compulsory heterosexuality, which positions women as erotic objects of the male gaze.
- Full Text:
- Authors: Pienaar, Kiran M , Bekker, Ian
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469223 , vital:77221 , https://doi.org/10.2989/16073610709486480
- Description: This article presents the results of a study on the discursive construction of one aspect of gender identity, namely the female physical ideal. It reports on an analysis of the discourses of the disciplined female body, as these are drawn upon in two conversations between a group of young, Western female university students. The conversations were elicited in August 2005 using a stimulus exercise designed to encourage discussion on issues relating to female body image, such as the notion of the ideal female body, dieting and plastic surgery. Using the tools of Critical Discourse Analysis (CDA) (Fairclough, 2001) the article analyses four related discourses, namely the pro-diet discourse, the discourse of the healthy body, the discourse of studied indifference and the discourse of the sexually attractive female body, in terms of how these discourses encode different, sometimes contradictory ideologies of the Western female body ideal. The article concludes that the discourse of the sexually attractive female body emerges as dominant in these conversational extracts and that, by colonising the other discourses, it legitimates its ethic of compulsory heterosexuality, which positions women as erotic objects of the male gaze.
- Full Text:
The C-Band : continuum mapping and measuring the radio environment
- Authors: King, Oliver Gray
- Date: 2007 , 2013-07-01
- Identifier: vital:5449 , http://hdl.handle.net/10962/d1004744
- Description: Voice-enabled applications, applications that interact with a user via an audio channel, are used extensively today. Their use is growing as speech related technologies improve, as speech is one of the most natural methods of interaction. They can provide customer support as IVRs, can be used as an assistive technology, or can become an aural interface to the Internet. Given that the telephone is used extensively throughout the globe, the number of potential users of voice-enabled applications is very high. VoiceXML is a popular, open, high-level, standard means of creating voice-enabled applications which was designed to bring the benefits of web based development to services. While VoiceXML is an ideal language for creating these applications, VoiceXML gateways, the hardware and software responsible for interpreting VoiceXML applications and interfacing with the PSTN, are still expensive and so there is a need for a low-cost gateway. Asterisk, and open-source, TDM/VoIP telephony platform, can be used as a low-cost PSTN interface. This thesis investigates adding a VoiceXML service to Asterisk, creating a low-cost VoiceXML prototype gateway which is able to render voice-enabled applications. Following the Component-Based Software Engineering (CBSE) paradigm, the VoiceXML gateway is divided into a set of components which are sourced from the open-source community, and integrated to create the gateway. The browser requires a VoiceXML interpreter (OpenVXI), a Text-To-Speech engine (Festival) and a speech recognition engine (Sphinx 4). The integration of the components results in a low-cost, open-source VoiceXML gateway. System tests show that the integration of the components was successful, and that the system can handle concurrent calls. A fully compliant version of the gateway can be used in the real world to render voice-enabled applications at a low cost.
- Full Text:
- Authors: King, Oliver Gray
- Date: 2007 , 2013-07-01
- Identifier: vital:5449 , http://hdl.handle.net/10962/d1004744
- Description: Voice-enabled applications, applications that interact with a user via an audio channel, are used extensively today. Their use is growing as speech related technologies improve, as speech is one of the most natural methods of interaction. They can provide customer support as IVRs, can be used as an assistive technology, or can become an aural interface to the Internet. Given that the telephone is used extensively throughout the globe, the number of potential users of voice-enabled applications is very high. VoiceXML is a popular, open, high-level, standard means of creating voice-enabled applications which was designed to bring the benefits of web based development to services. While VoiceXML is an ideal language for creating these applications, VoiceXML gateways, the hardware and software responsible for interpreting VoiceXML applications and interfacing with the PSTN, are still expensive and so there is a need for a low-cost gateway. Asterisk, and open-source, TDM/VoIP telephony platform, can be used as a low-cost PSTN interface. This thesis investigates adding a VoiceXML service to Asterisk, creating a low-cost VoiceXML prototype gateway which is able to render voice-enabled applications. Following the Component-Based Software Engineering (CBSE) paradigm, the VoiceXML gateway is divided into a set of components which are sourced from the open-source community, and integrated to create the gateway. The browser requires a VoiceXML interpreter (OpenVXI), a Text-To-Speech engine (Festival) and a speech recognition engine (Sphinx 4). The integration of the components results in a low-cost, open-source VoiceXML gateway. System tests show that the integration of the components was successful, and that the system can handle concurrent calls. A fully compliant version of the gateway can be used in the real world to render voice-enabled applications at a low cost.
- Full Text:
The comparison of in vitro release methods for the evaluation of oxytocin release from Pluronic® F127 parenteral formulations
- Chaibva, Faith A, Walker, Roderick B
- Authors: Chaibva, Faith A , Walker, Roderick B
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6351 , http://hdl.handle.net/10962/d1006033
- Description: The objective of these studies was to develop a discriminatory in vitro release test for assessing formulation factors that may affect oxytocin (OT) release during formulation development studies of a Pluronic® F127 OT in situ gel-forming parenteral dosage form. An appropriate release assessment method should be able to discriminate between the performance of different formulation compositions (1, 2), and this was the primary criterion used for selection of an appropriate test procedure during the test method development process. ANOVA and the difference (f1) and similarity (f2)factors were used to evaluate the discriminatory behavior of different test methods that were investigated in these studies. The in vitro release tests that were investigated included the use of USP Apparatus 1, 2, and 3; a dialysis bag in USP Apparatus 2; and a membrane-less diffusion method. It was concluded that the use of USP Apparatus 3 was best able to discriminate between OT release for the different formulations tested. USP Apparatus 3 was thus considered the most suitable in vitro release test apparatus for studying formulation factors affecting OT release during the development of a parenteral dosage form prepared using Pluronic® F127.
- Full Text:
- Authors: Chaibva, Faith A , Walker, Roderick B
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6351 , http://hdl.handle.net/10962/d1006033
- Description: The objective of these studies was to develop a discriminatory in vitro release test for assessing formulation factors that may affect oxytocin (OT) release during formulation development studies of a Pluronic® F127 OT in situ gel-forming parenteral dosage form. An appropriate release assessment method should be able to discriminate between the performance of different formulation compositions (1, 2), and this was the primary criterion used for selection of an appropriate test procedure during the test method development process. ANOVA and the difference (f1) and similarity (f2)factors were used to evaluate the discriminatory behavior of different test methods that were investigated in these studies. The in vitro release tests that were investigated included the use of USP Apparatus 1, 2, and 3; a dialysis bag in USP Apparatus 2; and a membrane-less diffusion method. It was concluded that the use of USP Apparatus 3 was best able to discriminate between OT release for the different formulations tested. USP Apparatus 3 was thus considered the most suitable in vitro release test apparatus for studying formulation factors affecting OT release during the development of a parenteral dosage form prepared using Pluronic® F127.
- Full Text:
The continued viability of the discretionary Inter vivos trust as an instrument for estate planning
- Lötter, Therésilda Sieglinde
- Authors: Lötter, Therésilda Sieglinde
- Date: 2007
- Subjects: Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MCom
- Identifier: vital:900 , http://hdl.handle.net/10962/d1006148 , Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Description: The purpose of this study is to determine whether a discretionary inter vivos trust is still an effective instrument for estate planning. The process of estate planning, the role the trust plays in it and the background to the trust are described. The taxability and tax saving opportunities when the trust are utilised are discussed in the light of the Estate Duty Act, 45 of 1955, the Income Tax Act, 58 of 1962 (including the Eighth Schedule thereof) and the Transfer Duty Act, 40 of 1949. The opinions of tax and legal authorities in articles and relevant case law are also discussed. The impact of the "letter of wishes" on the stipulations of the trust deed is examined. Amendments to the Income Tax Act have placed a limit on the use of a trust for estate planning through a number of anti-avoidance measures, the introduction of a capital gains tax (in the Eighth Schedule) and the imposition of a high tax rate. The increase in the deduction granted in arriving at the dutiable amount of an estate, in terms of section 4A of the Estate Duty Act, from R1 500 000 to R2 500 000 has imposed a further limit on the use of the trust as an instrument in estate planning. The research demonstrates that, notwithstanding the amendments to the Income Tax Act, the trust still is a viable instrument, mainly because the trust operates as a conduit and because of its potential use in dividing taxable income amongst a number of beneficiaries. The stipulations included in the trust deed and the "letter of wishes" (if one exists), must be thought through carefully when estate planning is done, as it can give rise to the application of the general and specific anti-avoidance provisions as included in sections 7 and 103 of this Act. The research also concludes that, in assessing the effectiveness of the trust as an instrument in tax planning, the disadvantage of paying the higher transfer duty when the immovable asset is transferred to the trust should be weighed up against the possible saving in income tax and estate duty at a later stage. It is also clear that most assets owned by the trust are tax neutral, whilst many of the amendments under discussion deal with the taxability of trust income. The quantitative considerations underlying the use of the trust as part of the estate plan, remain unchanged. The research concludes by providing a framework of quantitative and qualitative criteria that can be used by an estate planner to determine whether it will be advantageous to transfer an asset to the trust to achieve the objectives of the estate plan.
- Full Text:
- Authors: Lötter, Therésilda Sieglinde
- Date: 2007
- Subjects: Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MCom
- Identifier: vital:900 , http://hdl.handle.net/10962/d1006148 , Taxation -- Law and legislation -- South Africa , Trusts and trustees -- South Africa , Trusts and trustees -- Taxation -- South Africa , Estate planning -- South Africa , Estates (Law) -- South Africa
- Description: The purpose of this study is to determine whether a discretionary inter vivos trust is still an effective instrument for estate planning. The process of estate planning, the role the trust plays in it and the background to the trust are described. The taxability and tax saving opportunities when the trust are utilised are discussed in the light of the Estate Duty Act, 45 of 1955, the Income Tax Act, 58 of 1962 (including the Eighth Schedule thereof) and the Transfer Duty Act, 40 of 1949. The opinions of tax and legal authorities in articles and relevant case law are also discussed. The impact of the "letter of wishes" on the stipulations of the trust deed is examined. Amendments to the Income Tax Act have placed a limit on the use of a trust for estate planning through a number of anti-avoidance measures, the introduction of a capital gains tax (in the Eighth Schedule) and the imposition of a high tax rate. The increase in the deduction granted in arriving at the dutiable amount of an estate, in terms of section 4A of the Estate Duty Act, from R1 500 000 to R2 500 000 has imposed a further limit on the use of the trust as an instrument in estate planning. The research demonstrates that, notwithstanding the amendments to the Income Tax Act, the trust still is a viable instrument, mainly because the trust operates as a conduit and because of its potential use in dividing taxable income amongst a number of beneficiaries. The stipulations included in the trust deed and the "letter of wishes" (if one exists), must be thought through carefully when estate planning is done, as it can give rise to the application of the general and specific anti-avoidance provisions as included in sections 7 and 103 of this Act. The research also concludes that, in assessing the effectiveness of the trust as an instrument in tax planning, the disadvantage of paying the higher transfer duty when the immovable asset is transferred to the trust should be weighed up against the possible saving in income tax and estate duty at a later stage. It is also clear that most assets owned by the trust are tax neutral, whilst many of the amendments under discussion deal with the taxability of trust income. The quantitative considerations underlying the use of the trust as part of the estate plan, remain unchanged. The research concludes by providing a framework of quantitative and qualitative criteria that can be used by an estate planner to determine whether it will be advantageous to transfer an asset to the trust to achieve the objectives of the estate plan.
- Full Text:
The cost of credit in the micro-finance industry in South Africa
- Authors: Campbell, Jonathan
- Date: 2007
- Subjects: Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3667 , http://hdl.handle.net/10962/d1003182 , Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Description: This thesis analyses the cost of credit in the micro-finance industry in South Africa. The study situates micro-lending agreements within the law of contract, beginning with an examination of contractual fairness in terms of the common law: the fundamental principle of freedom of contract that underpins the common law of contract; the principle that agreements contrary to public policy should not be enforced; and the impetus given by constitutional values that inform public policy. In regard to moneylending transactions, common law usury law will be explained. The study then goes on to trace the origins and rapid growth of the micro-finance industry which was made possible by its exemption in 1992 from the Usury Act 73 of 1968. The upshot of this development was that registered micro-lenders have for nearly 14 years charged excessive interest rates, and continue to do so. The dire socio-economic impact of these high interest rates on individual consumers and lowincome communities is then demonstrated: how borrowers of small loans soon become over-indebted; the loss of billions of rands every year to low-income communities in the form of interest on micro-loans. The study then shifts to the legislative response to the need for consumer protection in regard to consumer credit. The extensive credit law review process is explained, resulting ultimately in the National Credit Act 34 of 2005, which allows the Minister to prescribe limits on interest rates and fees in all sectors of the consumer credit market. The prescribed limits on the cost of credit in the micro-finance sector are thoroughly explained and analysed, with particular reference to the implications of each element of the credit costing structure, and the combined impact of the total cost of credit on different types and sizes of loans. The envisaged maximum interest and fees will markedly alter the positions of micro-lenders and consumers, and receive careful analysis. The study closes with a summary of findings in the thesis, which includes suggested amendments to the National Credit Regulations and a review of possible legal challenges to the high cost of credit on smaller loans.
- Full Text:
- Authors: Campbell, Jonathan
- Date: 2007
- Subjects: Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3667 , http://hdl.handle.net/10962/d1003182 , Contracts -- South Africa , Credit -- Law and legislation -- South Africa , Microfinance -- South Africa , Usury laws -- South Africa
- Description: This thesis analyses the cost of credit in the micro-finance industry in South Africa. The study situates micro-lending agreements within the law of contract, beginning with an examination of contractual fairness in terms of the common law: the fundamental principle of freedom of contract that underpins the common law of contract; the principle that agreements contrary to public policy should not be enforced; and the impetus given by constitutional values that inform public policy. In regard to moneylending transactions, common law usury law will be explained. The study then goes on to trace the origins and rapid growth of the micro-finance industry which was made possible by its exemption in 1992 from the Usury Act 73 of 1968. The upshot of this development was that registered micro-lenders have for nearly 14 years charged excessive interest rates, and continue to do so. The dire socio-economic impact of these high interest rates on individual consumers and lowincome communities is then demonstrated: how borrowers of small loans soon become over-indebted; the loss of billions of rands every year to low-income communities in the form of interest on micro-loans. The study then shifts to the legislative response to the need for consumer protection in regard to consumer credit. The extensive credit law review process is explained, resulting ultimately in the National Credit Act 34 of 2005, which allows the Minister to prescribe limits on interest rates and fees in all sectors of the consumer credit market. The prescribed limits on the cost of credit in the micro-finance sector are thoroughly explained and analysed, with particular reference to the implications of each element of the credit costing structure, and the combined impact of the total cost of credit on different types and sizes of loans. The envisaged maximum interest and fees will markedly alter the positions of micro-lenders and consumers, and receive careful analysis. The study closes with a summary of findings in the thesis, which includes suggested amendments to the National Credit Regulations and a review of possible legal challenges to the high cost of credit on smaller loans.
- Full Text:
The decline of water hyacinth on Lake Victoria was due to biological control by Neochetina spp
- Wilson, J R U, Ajuonub, O, Center, R D, Hill, Martin P, Julien, M H, Katagira, F F, Neuenschwander, P, Njoka, S W, Ogwang, J, Reeder, R H, Van, T
- Authors: Wilson, J R U , Ajuonub, O , Center, R D , Hill, Martin P , Julien, M H , Katagira, F F , Neuenschwander, P , Njoka, S W , Ogwang, J , Reeder, R H , Van, T
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6927 , http://hdl.handle.net/10962/d1011918 , https://orcid.org/0000-0003-0579-5298
- Description: There has been some debate recently about the cause of the decline of water hyacinth on Lake Victoria. While much of this evidence points to classical biological control as the major factor, the El Niño associated weather pattern of the last quarter of 1997 and the first half of 1998 has confused the issue. We argue first that the reductions in water hyacinth on Lake Victoria were ultimately caused by the widespread and significant damage to plants by Neochetina spp., although this process was increased by the stormy weather associated with the El Niño event; second that increased waves and current on Lake Victoria caused by El Niño redistributed water hyacinth plants around the lake; and third that a major lake-wide resurgence of water hyacinth plants on Lake Victoria has not occurred and will not occur unless the weevil populations are disrupted. We conclude that the population crash of water hyacinth on Lake Victoria would not have occurred in the absence of the weevils, but that it may have been hastened by stormy weather associated with the El Niño event.
- Full Text:
- Authors: Wilson, J R U , Ajuonub, O , Center, R D , Hill, Martin P , Julien, M H , Katagira, F F , Neuenschwander, P , Njoka, S W , Ogwang, J , Reeder, R H , Van, T
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6927 , http://hdl.handle.net/10962/d1011918 , https://orcid.org/0000-0003-0579-5298
- Description: There has been some debate recently about the cause of the decline of water hyacinth on Lake Victoria. While much of this evidence points to classical biological control as the major factor, the El Niño associated weather pattern of the last quarter of 1997 and the first half of 1998 has confused the issue. We argue first that the reductions in water hyacinth on Lake Victoria were ultimately caused by the widespread and significant damage to plants by Neochetina spp., although this process was increased by the stormy weather associated with the El Niño event; second that increased waves and current on Lake Victoria caused by El Niño redistributed water hyacinth plants around the lake; and third that a major lake-wide resurgence of water hyacinth plants on Lake Victoria has not occurred and will not occur unless the weevil populations are disrupted. We conclude that the population crash of water hyacinth on Lake Victoria would not have occurred in the absence of the weevils, but that it may have been hastened by stormy weather associated with the El Niño event.
- Full Text:
The demand for broad money (M2) in Botswana
- Authors: Tsheole, Thapelo
- Date: 2007
- Subjects: Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:966 , http://hdl.handle.net/10962/d1002700 , Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Description: There has been extensive theoretical and empirical research on the subject of demand for money function. This particularly stems from the important role demand for money plays in macroeconomic analysis, especially in the design and implementation of monetary policy. The increase in studies, especially in developing countries, can also be attributed to a number of factors like: the impact of moving towards flexible exchange rate regimes, globalisation of financial markets, ongoing financial liberalisation, innovations in domestic financial products, the advancement in econometrics techniques and other country-specific events. This study estimates and examines the nature and stability of the demand for broad money (M2) in Botswana. This is particularly important in that the usefulness of a money demand function in the conduct of monetary policy depends crucially on its stability. The stability of the money demand function is crucial in that a stable money demand function would mean that the quantity of money is predictably related to a set of key economic variables linking money and the real economic sector. Therefore, this will help central banks to select appropriate monetary policy actions. Based on the findings, the study also proposes policy interventions. The vast majority of the literature on demand for money has underscored the fact that variable selection and representation, and the framework chosen are the two major issues relevant to modelling and estimation of the demand for money function. In modelling and estimating the demand for money function in Botswana, this study surveys a stream of theoretical and empirical literature on money demand in developed and developing countries, including countries that have similar financial sector similar to Botswana. Due consideration is also given to the macroeconomic and financial sector development in Botswana to help in the identification of the variables that are included in the demand for money equation. Most importantly, this helped in getting meaningful results that are free from theoretical and estimation problems. In particular, this study applied the multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) to estimate the relationship between broad money (M2), real income, interest rate, South African treasury bill rate, inflation rate and US dollar/pula bilateral exchange rate. The study obtains one unique long run relationship between money and the scale and opportunity cost variables. The coefficients of the long run relationship are then modelled along the general to specific approach as proposed by Campos, Ericsson and Hendry (2005). In this type of approach the general model is reduced by sequential elimination of statistically insignificant variables and checking the validity of the reductions at every stage to ensure congruence of the finally selected parsimonious model. In accordance with the economic quantity theory of money, the long run income elasticity obtained is 0.8021, which is close to the value one (unitary) suggested by economic theory. The coefficients of real income, exchange and inflation rate have the expected positive signs and were significant in the long run. Therefore, the long run demand for money (M2) in Botswana was found to be positively affected by real income, inflation rate and exchange rate. The lack of statistical significant of the own rate of money (88 day commercial bank deposit rate) and the foreign opportunity cost variable (South African Treasury bill rate) is attributed to multi-collinearity problems between these two interest rates. This could be caused by the fact that short term rates in Botswana are very responsive to movements in the money markets rates in South Africa. The short run dynamics of the demand for money function shows the slow speed of adjustment to equilibrium of about 2.9 percent in the first quarter and this is reflective of the lack of sufficient availability of banking services and the low returns on financial assets which could allow economic agents to re-establish equilibrium levels of money holdings faster. The final parsimonious model obtained clearly reflects a well specified stable demand for money function. Therefore, based on the findings we can be precise in stating that targeting a monetary aggregate can be a viable policy for the monetary authorities in Botswana.
- Full Text:
- Authors: Tsheole, Thapelo
- Date: 2007
- Subjects: Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:966 , http://hdl.handle.net/10962/d1002700 , Monetary policy -- Botswana , Demand for money -- Botswana , Botswana -- Economic conditions , Quantity theory of money
- Description: There has been extensive theoretical and empirical research on the subject of demand for money function. This particularly stems from the important role demand for money plays in macroeconomic analysis, especially in the design and implementation of monetary policy. The increase in studies, especially in developing countries, can also be attributed to a number of factors like: the impact of moving towards flexible exchange rate regimes, globalisation of financial markets, ongoing financial liberalisation, innovations in domestic financial products, the advancement in econometrics techniques and other country-specific events. This study estimates and examines the nature and stability of the demand for broad money (M2) in Botswana. This is particularly important in that the usefulness of a money demand function in the conduct of monetary policy depends crucially on its stability. The stability of the money demand function is crucial in that a stable money demand function would mean that the quantity of money is predictably related to a set of key economic variables linking money and the real economic sector. Therefore, this will help central banks to select appropriate monetary policy actions. Based on the findings, the study also proposes policy interventions. The vast majority of the literature on demand for money has underscored the fact that variable selection and representation, and the framework chosen are the two major issues relevant to modelling and estimation of the demand for money function. In modelling and estimating the demand for money function in Botswana, this study surveys a stream of theoretical and empirical literature on money demand in developed and developing countries, including countries that have similar financial sector similar to Botswana. Due consideration is also given to the macroeconomic and financial sector development in Botswana to help in the identification of the variables that are included in the demand for money equation. Most importantly, this helped in getting meaningful results that are free from theoretical and estimation problems. In particular, this study applied the multivariate cointegration approach as proposed by Johansen (1988) and Johansen and Juselius (1990) to estimate the relationship between broad money (M2), real income, interest rate, South African treasury bill rate, inflation rate and US dollar/pula bilateral exchange rate. The study obtains one unique long run relationship between money and the scale and opportunity cost variables. The coefficients of the long run relationship are then modelled along the general to specific approach as proposed by Campos, Ericsson and Hendry (2005). In this type of approach the general model is reduced by sequential elimination of statistically insignificant variables and checking the validity of the reductions at every stage to ensure congruence of the finally selected parsimonious model. In accordance with the economic quantity theory of money, the long run income elasticity obtained is 0.8021, which is close to the value one (unitary) suggested by economic theory. The coefficients of real income, exchange and inflation rate have the expected positive signs and were significant in the long run. Therefore, the long run demand for money (M2) in Botswana was found to be positively affected by real income, inflation rate and exchange rate. The lack of statistical significant of the own rate of money (88 day commercial bank deposit rate) and the foreign opportunity cost variable (South African Treasury bill rate) is attributed to multi-collinearity problems between these two interest rates. This could be caused by the fact that short term rates in Botswana are very responsive to movements in the money markets rates in South Africa. The short run dynamics of the demand for money function shows the slow speed of adjustment to equilibrium of about 2.9 percent in the first quarter and this is reflective of the lack of sufficient availability of banking services and the low returns on financial assets which could allow economic agents to re-establish equilibrium levels of money holdings faster. The final parsimonious model obtained clearly reflects a well specified stable demand for money function. Therefore, based on the findings we can be precise in stating that targeting a monetary aggregate can be a viable policy for the monetary authorities in Botswana.
- Full Text:
The deployment of an e-commerce platform and related projects in a rural area in South Africa
- Dalvit, Lorenzo, Muyingi, H Hyppolite, Terzoli, Alfredo, Thinyane, Mamello
- Authors: Dalvit, Lorenzo , Muyingi, H Hyppolite , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428545 , vital:72519 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information%20Communica-tion%20Technologies%20%20page%20410.pdf?sequence=1andisAllowed=y#page=256
- Description: In our paper we describe the development and deployment of an ecommerce platform in Dwesa, a rural area in the former homeland of Transkei in South Africa. The system is designed to promote tourism and advertise local arts, crafts and music, and it entails a number of re-lated projects. Deployment of infrastructure, technical support, promo-tion of the initiative and teaching of computer literacy take place during monthly visits of approximately one week, and involve young research-ers from two universities (one previously disadvantaged; the other his-torically privileged). This ensures a synergy between technical exper-tise and understanding of the local context. Findings so far emphasise the importance of contextualising the intervention to suit local needs and adjust to the local context. The platform is currently being extended to include e-government, e-learning and e-health capabilities. If proven successful, this model can be exported to similar areas in South africa and in the rest of Africa. This could open up potential opportunities for the still unexplored market for ICT in rural Africa.
- Full Text:
- Authors: Dalvit, Lorenzo , Muyingi, H Hyppolite , Terzoli, Alfredo , Thinyane, Mamello
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428545 , vital:72519 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information%20Communica-tion%20Technologies%20%20page%20410.pdf?sequence=1andisAllowed=y#page=256
- Description: In our paper we describe the development and deployment of an ecommerce platform in Dwesa, a rural area in the former homeland of Transkei in South Africa. The system is designed to promote tourism and advertise local arts, crafts and music, and it entails a number of re-lated projects. Deployment of infrastructure, technical support, promo-tion of the initiative and teaching of computer literacy take place during monthly visits of approximately one week, and involve young research-ers from two universities (one previously disadvantaged; the other his-torically privileged). This ensures a synergy between technical exper-tise and understanding of the local context. Findings so far emphasise the importance of contextualising the intervention to suit local needs and adjust to the local context. The platform is currently being extended to include e-government, e-learning and e-health capabilities. If proven successful, this model can be exported to similar areas in South africa and in the rest of Africa. This could open up potential opportunities for the still unexplored market for ICT in rural Africa.
- Full Text:
The design and assessment of an integrated municipal waste beneficiation facility : towards improved sewage sludge management in developing countries
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
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- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
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The development and transfer of core competencies in multinational corporations : a study of three South African originated multinational corporations, compared and contrasted with a leading United States multinational
- Authors: Harvey, Neil M
- Date: 2007
- Subjects: Management -- South Africa International business enterprises -- South Afrca International business enterprises -- United States Core competencies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1197 , http://hdl.handle.net/10962/d1008369
- Description: The thesis studies the development and transfer of core competencies in multinational corporations. It aims to advance the general body of knowledge relating to core competencies, to have practical applicability for management practitioners and academics, to explain how three companies from South Africa became global leaders in their fields and to examine the lessons they learned about international business. Three South African originated multinationals and a US multinational company were studied. The basic methodology is a case study. The methods of research were personal interviews, telephone interviews, written questionnaires, documents, archival records and direct observations. Value chains were used to evaluate the effectiveness of methods of development and transfer and the success of transfer of core competencies. It is concluded that different and multiple methods are needed to develop and transfer core competencies. The effectiveness of methods varies by company and value chain location. There is a significant high degree of correlation between the ratings of success in transferring core competencies and the effectiveness of the methods used to transfer them. This gives substantial credibility to the information provided by the companies and highlights the importance of selecting appropriate methods. There are some variances between the research results and established literature on the development and transfer of core competencies. There are notable differences between the companies from South Africa and the US multinational on the effectiveness of methods used to develop and transfer core competencies. There are also areas where all the companies are in accord. "Roadmaps" covering the effectiveness of methods for developing and transferring core competencies in different locations in a value chain are presented. Practical examples of the companies' actions relating to acquisitions and post-acquisition integration, their experiences in different countries, challenges they face, the methods used to assess transfer, avoid pitfalls and improve transfer, and other issues are also provided.The success of the multinationals from South Africa is explained by a combination of history, competitive factor conditions, management practices, attributes and leadership. The conclusions of the thesis are followed by recommendations on how to improve the management, development and transfer of core competencies.
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- Authors: Harvey, Neil M
- Date: 2007
- Subjects: Management -- South Africa International business enterprises -- South Afrca International business enterprises -- United States Core competencies
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1197 , http://hdl.handle.net/10962/d1008369
- Description: The thesis studies the development and transfer of core competencies in multinational corporations. It aims to advance the general body of knowledge relating to core competencies, to have practical applicability for management practitioners and academics, to explain how three companies from South Africa became global leaders in their fields and to examine the lessons they learned about international business. Three South African originated multinationals and a US multinational company were studied. The basic methodology is a case study. The methods of research were personal interviews, telephone interviews, written questionnaires, documents, archival records and direct observations. Value chains were used to evaluate the effectiveness of methods of development and transfer and the success of transfer of core competencies. It is concluded that different and multiple methods are needed to develop and transfer core competencies. The effectiveness of methods varies by company and value chain location. There is a significant high degree of correlation between the ratings of success in transferring core competencies and the effectiveness of the methods used to transfer them. This gives substantial credibility to the information provided by the companies and highlights the importance of selecting appropriate methods. There are some variances between the research results and established literature on the development and transfer of core competencies. There are notable differences between the companies from South Africa and the US multinational on the effectiveness of methods used to develop and transfer core competencies. There are also areas where all the companies are in accord. "Roadmaps" covering the effectiveness of methods for developing and transferring core competencies in different locations in a value chain are presented. Practical examples of the companies' actions relating to acquisitions and post-acquisition integration, their experiences in different countries, challenges they face, the methods used to assess transfer, avoid pitfalls and improve transfer, and other issues are also provided.The success of the multinationals from South Africa is explained by a combination of history, competitive factor conditions, management practices, attributes and leadership. The conclusions of the thesis are followed by recommendations on how to improve the management, development and transfer of core competencies.
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