Marginalisation and demographic change in the semi-arid Karoo, South Africa
- Nel, Etienne L, Hill, Trevor R
- Authors: Nel, Etienne L , Hill, Trevor R
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6719 , http://hdl.handle.net/10962/d1006792
- Description: Semi-arid areas are often considered to be environmentally and economically marginal, a situation which has been exacerbated by economic change, shifts in agricultural production and land use, and changing state policy. These themes are explored with reference to a semi-arid landscape, namely the Karoo, which covers some 40% of the geographic space of South Africa and is used primarily for extensive livestock farming. Despite long-term decline in agricultural output, the traditional mainstay of the region, and weakening small town economies, the Karoo's population and the economies of its largest service centres are growing. There are, real socio-economic needs and development backlogs, and the situation has been exacerbated by recent political marginalisation. In this study, the small towns of the region are focal points of investigation and provide a lens to investigate the changing demographic and economic dynamics of the Karoo. Most of the region's population lives in these centres which are service, collection, and distribution points for what traditionally has been an agriculture-based regional economy. This paper explores the concept of marginalisation with specific reference to historical, economic, and demographic change.
- Full Text:
- Date Issued: 2008
- Authors: Nel, Etienne L , Hill, Trevor R
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6719 , http://hdl.handle.net/10962/d1006792
- Description: Semi-arid areas are often considered to be environmentally and economically marginal, a situation which has been exacerbated by economic change, shifts in agricultural production and land use, and changing state policy. These themes are explored with reference to a semi-arid landscape, namely the Karoo, which covers some 40% of the geographic space of South Africa and is used primarily for extensive livestock farming. Despite long-term decline in agricultural output, the traditional mainstay of the region, and weakening small town economies, the Karoo's population and the economies of its largest service centres are growing. There are, real socio-economic needs and development backlogs, and the situation has been exacerbated by recent political marginalisation. In this study, the small towns of the region are focal points of investigation and provide a lens to investigate the changing demographic and economic dynamics of the Karoo. Most of the region's population lives in these centres which are service, collection, and distribution points for what traditionally has been an agriculture-based regional economy. This paper explores the concept of marginalisation with specific reference to historical, economic, and demographic change.
- Full Text:
- Date Issued: 2008
Rock magnetic stratigraphy of a mafic layered sill: a key to the Karoo volcanics plumbing system
- Maes, S M, Ferré, E E, Tikoff, B, Brown, P E, Marsh, Julian S
- Authors: Maes, S M , Ferré, E E , Tikoff, B , Brown, P E , Marsh, Julian S
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144901 , vital:38389 , https://doi.org/10.1016/j.jvolgeores.2005.07.038
- Description: The Insizwa sill is an 1 km-thick subhorizontal layered mafic intrusion and part of the Karoo Large Igneous Province in South Africa. This well-exposed intrusion consists of several superimposed petrologically and geochemically distinct units. Magnetic methods were used to study the intrusion in order to constrain the physical processes active in these types of bodies during crystallization. Rock magnetism studies indicate that within different petrologic units bulk susceptibility is controlled by primary magnetite (with minor pyrrhotite) and/or paramagnetic minerals (olivine, pyroxene). New magnetic data based on 659 specimens obtained from 3 vertical borehole cores, each spaced 5 km apart, confirm the prominent vertical zonation in low field magnetic susceptibility (Klf), degree of anisotropy (Pj) and orientation of the anisotropy of magnetic susceptibility (AMS) axes.
- Full Text:
- Date Issued: 2008
- Authors: Maes, S M , Ferré, E E , Tikoff, B , Brown, P E , Marsh, Julian S
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144901 , vital:38389 , https://doi.org/10.1016/j.jvolgeores.2005.07.038
- Description: The Insizwa sill is an 1 km-thick subhorizontal layered mafic intrusion and part of the Karoo Large Igneous Province in South Africa. This well-exposed intrusion consists of several superimposed petrologically and geochemically distinct units. Magnetic methods were used to study the intrusion in order to constrain the physical processes active in these types of bodies during crystallization. Rock magnetism studies indicate that within different petrologic units bulk susceptibility is controlled by primary magnetite (with minor pyrrhotite) and/or paramagnetic minerals (olivine, pyroxene). New magnetic data based on 659 specimens obtained from 3 vertical borehole cores, each spaced 5 km apart, confirm the prominent vertical zonation in low field magnetic susceptibility (Klf), degree of anisotropy (Pj) and orientation of the anisotropy of magnetic susceptibility (AMS) axes.
- Full Text:
- Date Issued: 2008
School principals' perceptions of team management : a multiple case-study of secondary schools
- Van der Mescht, Hennie, Tyala, Zakunzima
- Authors: Van der Mescht, Hennie , Tyala, Zakunzima
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6105 , http://hdl.handle.net/10962/d1009732
- Description: The notion of school management through teams (team management), though not a new phenomenon in South Africa, was formalized after the advent of democracy in 1994 and the subsequent reorganization of the education system. The concept was subsequently fleshed out in official documentation where the composition and roles of school management teams (SMTs) were elaborated upon. The notion of team management is rooted in theories that stress participation, notably site-based (school-based) management, teamwork, and distributed leadership. We report on a study in which the perceptions of secondary school principals, in Grahamstown, South Africa, of team management were explored. The study was interpretive in orientation, and utilized qualitative data gathering techniques in all (ten) of the state-aided secondary schools in Grahamstown in the Eastern Cape province. We found that, while team management was generally welcomed and even celebrated by principals, there were fundamental tensions surrounding principals' understanding of their leadership roles in a team context. We consider the implications of these findings for leadership development in the context of team management.
- Full Text:
- Date Issued: 2008
- Authors: Van der Mescht, Hennie , Tyala, Zakunzima
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6105 , http://hdl.handle.net/10962/d1009732
- Description: The notion of school management through teams (team management), though not a new phenomenon in South Africa, was formalized after the advent of democracy in 1994 and the subsequent reorganization of the education system. The concept was subsequently fleshed out in official documentation where the composition and roles of school management teams (SMTs) were elaborated upon. The notion of team management is rooted in theories that stress participation, notably site-based (school-based) management, teamwork, and distributed leadership. We report on a study in which the perceptions of secondary school principals, in Grahamstown, South Africa, of team management were explored. The study was interpretive in orientation, and utilized qualitative data gathering techniques in all (ten) of the state-aided secondary schools in Grahamstown in the Eastern Cape province. We found that, while team management was generally welcomed and even celebrated by principals, there were fundamental tensions surrounding principals' understanding of their leadership roles in a team context. We consider the implications of these findings for leadership development in the context of team management.
- Full Text:
- Date Issued: 2008
Tracing and erasure in Kathryn Smith's Psychogeographies: the washing away of wrongs
- Authors: de Jager, Maureen
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147413 , vital:38634 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC31057
- Description: Kathryn Smith's Psychogeographies: The Washing Away of Wrongs is a series of twelve prints comprising photographs and handwritten text, wherein she records her 'pilgrimage' to the former homes of British serial killer Dennis Nilsen. As such, it utilises photographic and autographic traces to 'track' the elusive traces left by Nilsen. Given the lapse of two decades between Nilsen's arrest and Smith's visit, the traces of Nilsen's 'wrongs' seem all but erased by the banal façade of suburban living which has continued on, regardless. In taking this as a starting point, the following article considers the motif of absence that characterises Smith's work as intrinsic to traces per se.
- Full Text:
- Date Issued: 2008
- Authors: de Jager, Maureen
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147413 , vital:38634 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC31057
- Description: Kathryn Smith's Psychogeographies: The Washing Away of Wrongs is a series of twelve prints comprising photographs and handwritten text, wherein she records her 'pilgrimage' to the former homes of British serial killer Dennis Nilsen. As such, it utilises photographic and autographic traces to 'track' the elusive traces left by Nilsen. Given the lapse of two decades between Nilsen's arrest and Smith's visit, the traces of Nilsen's 'wrongs' seem all but erased by the banal façade of suburban living which has continued on, regardless. In taking this as a starting point, the following article considers the motif of absence that characterises Smith's work as intrinsic to traces per se.
- Full Text:
- Date Issued: 2008
New Unity Movement Bulletin
- Date: 2007-04
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/31726 , vital:31740 , Bulk File 7
- Description: The Bulletin was the official newsletter of the New Unity Movement. It was published about twice a year and contained articles reflecting the organisation's views on resistance to the Apartheid government.
- Full Text: false
- Date Issued: 2007-04
- Date: 2007-04
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/31726 , vital:31740 , Bulk File 7
- Description: The Bulletin was the official newsletter of the New Unity Movement. It was published about twice a year and contained articles reflecting the organisation's views on resistance to the Apartheid government.
- Full Text: false
- Date Issued: 2007-04
Adjustment of commercial bank's interest rates and the effectiveness of monetary policy in South Africa
- Aziakpono, Meshach J, Wilson, Magdalene K, Manuel, Jason
- Authors: Aziakpono, Meshach J , Wilson, Magdalene K , Manuel, Jason
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469676 , vital:77277 , https://hdl.handle.net/10520/EJC33833
- Description: The study uses the asymmetric error correction model as in Scholnick (1996) and two wholesale bank interest rates (prime interbank lending and the negotiable certificate of deposit rates), to examine how market interest rates adjust to changes in the SARB official rate under different policy regimes in South Africa. The study covered the period between 1973 and 2004, which was divided into six sub-periods to reflect the different monetary policy regimes in South Africa. The results indicate a varying degree of adjustment under the different regimes, but clearly show that there was greater speed of adjustment under regimes that stress more market-oriented policies as opposed to control measures. The response of market Interest rates to monetary policy was quick and with high magnitude which suggest a fairly efficient money market. The evidence on the asymmetric adjustment was weak. On the whole, the results of this study suggest that a market-oriented policy would be more effective in transmitting the effects of the Bank's monetary policy stance to the rest of the economy.
- Full Text:
- Date Issued: 2007
- Authors: Aziakpono, Meshach J , Wilson, Magdalene K , Manuel, Jason
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469676 , vital:77277 , https://hdl.handle.net/10520/EJC33833
- Description: The study uses the asymmetric error correction model as in Scholnick (1996) and two wholesale bank interest rates (prime interbank lending and the negotiable certificate of deposit rates), to examine how market interest rates adjust to changes in the SARB official rate under different policy regimes in South Africa. The study covered the period between 1973 and 2004, which was divided into six sub-periods to reflect the different monetary policy regimes in South Africa. The results indicate a varying degree of adjustment under the different regimes, but clearly show that there was greater speed of adjustment under regimes that stress more market-oriented policies as opposed to control measures. The response of market Interest rates to monetary policy was quick and with high magnitude which suggest a fairly efficient money market. The evidence on the asymmetric adjustment was weak. On the whole, the results of this study suggest that a market-oriented policy would be more effective in transmitting the effects of the Bank's monetary policy stance to the rest of the economy.
- Full Text:
- Date Issued: 2007
Asymmetric tariff reduction within the SADC protocol on trade and its implications for industrial development within member states
- Authors: Mutambara, Tsitsi E
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/477798 , vital:78125 , https://hdl.handle.net/10520/AJA20062184_29
- Description: The Southern African Development Community (SADC) aims to facilitate and attain deeper economic integration and industrial development among its members. To achieve these objectives, the grouping developed the SADC Protocol on Trade whose implementation began in 2000. While this Protocol is mainly a trade instrument, this article seeks to explore how it could be used to facilitate industrial development instead of using it solely for trade integration. In analysing this Protocol it has been observed that it has specific provisions that address issues on industrial development within the grouping. These provisions are Part Two Article 3 and Part Four Article 21. As the region progresses in implementing the Protocol, the aforementioned Articles could be utilised to facilitate industrial development. Theoretical debates upon which these Articles could be used to facilitate industrial development rest on the infant industry argument, the static and dynamic effects of economic integration. Limitations of the theoretical frameworks will be explored and how this could impact on industrial development initiatives by the grouping.
- Full Text:
- Date Issued: 2007
- Authors: Mutambara, Tsitsi E
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/477798 , vital:78125 , https://hdl.handle.net/10520/AJA20062184_29
- Description: The Southern African Development Community (SADC) aims to facilitate and attain deeper economic integration and industrial development among its members. To achieve these objectives, the grouping developed the SADC Protocol on Trade whose implementation began in 2000. While this Protocol is mainly a trade instrument, this article seeks to explore how it could be used to facilitate industrial development instead of using it solely for trade integration. In analysing this Protocol it has been observed that it has specific provisions that address issues on industrial development within the grouping. These provisions are Part Two Article 3 and Part Four Article 21. As the region progresses in implementing the Protocol, the aforementioned Articles could be utilised to facilitate industrial development. Theoretical debates upon which these Articles could be used to facilitate industrial development rest on the infant industry argument, the static and dynamic effects of economic integration. Limitations of the theoretical frameworks will be explored and how this could impact on industrial development initiatives by the grouping.
- Full Text:
- Date Issued: 2007
Enabling and constraining ICT practice in secondary schools: case studies in South Africa
- Hodgkinson-Williams, Cheryl, Siebörger, Ingrid, Terzoli, Alfredo
- Authors: Hodgkinson-Williams, Cheryl , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428923 , vital:72546 , https://www.inderscienceonline.com/doi/epdf/10.1504/IJKL.2007.015551
- Description: The use of Information Communication Technology (ICT) in education is being seen as a way of widening access to education, particularly in developing countries. This paper addresses the issue of ICT implemen-tation in secondary schools and focuses specifically on the practices that enable or constrain the successful implementation of ICT for teach-ing and learning activities. It reflects upon the lessons learned from a collective case study undertaken in 12 of the 13 secondary schools in Grahamstown in the Eastern Cape in South Africa. School principals and designated IT teachers were interviewed and on-site infrastructure audits conducted. This paper identifies a number of key enabling and constraining factors surrounding practical issues, including sufficient hardware, appropriate software and affordable connectivity, sufficient technical support and training, policy-related issues such as the role of national, provincial and school policy, the vital contribution of principal leadership and champion teachers as well as ongoing teacher profes-sional development coupled with a willingness to change.
- Full Text:
- Date Issued: 2007
- Authors: Hodgkinson-Williams, Cheryl , Siebörger, Ingrid , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428923 , vital:72546 , https://www.inderscienceonline.com/doi/epdf/10.1504/IJKL.2007.015551
- Description: The use of Information Communication Technology (ICT) in education is being seen as a way of widening access to education, particularly in developing countries. This paper addresses the issue of ICT implemen-tation in secondary schools and focuses specifically on the practices that enable or constrain the successful implementation of ICT for teach-ing and learning activities. It reflects upon the lessons learned from a collective case study undertaken in 12 of the 13 secondary schools in Grahamstown in the Eastern Cape in South Africa. School principals and designated IT teachers were interviewed and on-site infrastructure audits conducted. This paper identifies a number of key enabling and constraining factors surrounding practical issues, including sufficient hardware, appropriate software and affordable connectivity, sufficient technical support and training, policy-related issues such as the role of national, provincial and school policy, the vital contribution of principal leadership and champion teachers as well as ongoing teacher profes-sional development coupled with a willingness to change.
- Full Text:
- Date Issued: 2007
Enlarged arguments in Bantu : evidence from Chichewa
- Authors: Simango, Silvester R
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6140 , http://hdl.handle.net/10962/d1011592
- Description: This paper re-examines two types of constructions that have featured in the discussion of possessor ascension in Bantu: one type – an applicative construction – is associated with alienable possession, and the other – non-applicative – is associated with inalienable possession. The study shows that the former expresses affectedness, and that the possessor reading arises only by construal; whereas the latter expresses a part–whole relationship. The paper argues that the two constructions differ in more significant ways than has previously been acknowledged; and that their distinct derivations cannot be captured by traditional possessor ascension (PA) analyses. The putative “alienable” possessor constructions belong to the class of (benefactive) applicative constructions and should be analyzed as such. The paper proposes that the so-called “inalienable” possessor constructions can best be accounted for by positing the existence of “enlarged arguments” wherein the possessum functions as a nominal predicate which more narrowly pinpoints the locus of the action described by the verb.
- Full Text:
- Date Issued: 2007
- Authors: Simango, Silvester R
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6140 , http://hdl.handle.net/10962/d1011592
- Description: This paper re-examines two types of constructions that have featured in the discussion of possessor ascension in Bantu: one type – an applicative construction – is associated with alienable possession, and the other – non-applicative – is associated with inalienable possession. The study shows that the former expresses affectedness, and that the possessor reading arises only by construal; whereas the latter expresses a part–whole relationship. The paper argues that the two constructions differ in more significant ways than has previously been acknowledged; and that their distinct derivations cannot be captured by traditional possessor ascension (PA) analyses. The putative “alienable” possessor constructions belong to the class of (benefactive) applicative constructions and should be analyzed as such. The paper proposes that the so-called “inalienable” possessor constructions can best be accounted for by positing the existence of “enlarged arguments” wherein the possessum functions as a nominal predicate which more narrowly pinpoints the locus of the action described by the verb.
- Full Text:
- Date Issued: 2007
Forecasting recession in South Africa: A comparison of the yield curve and other economic indicators
- Khomo, Melvin M, Aziakpono, Meshach J
- Authors: Khomo, Melvin M , Aziakpono, Meshach J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469775 , vital:77293 , https://doi.org/10.1111/j.1813-6982.2007.00117.x
- Description: The paper uses the standard probit model proposed by Estrella and Mishkin (1996), as well as the modified probit model suggested by Dueker (1997), to examine the ability of the yield curve to predict recessions in South Africa, and compares its predictive power with other commonly used variables such as the growth rate of real money supply, changes in stock prices and the index of leading economic indicators. Compared with other indicators, real M3 growth does not provide much information about future recessions, whilst movements in the All‐Share index provide information for up to 12 months but do not do better than the yield curve. The index of leading economic indicators outperforms the yield spread in the short run up to 4 months but the yield spread performs better at longer horizons.
- Full Text:
- Date Issued: 2007
Forecasting recession in South Africa: A comparison of the yield curve and other economic indicators
- Authors: Khomo, Melvin M , Aziakpono, Meshach J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469775 , vital:77293 , https://doi.org/10.1111/j.1813-6982.2007.00117.x
- Description: The paper uses the standard probit model proposed by Estrella and Mishkin (1996), as well as the modified probit model suggested by Dueker (1997), to examine the ability of the yield curve to predict recessions in South Africa, and compares its predictive power with other commonly used variables such as the growth rate of real money supply, changes in stock prices and the index of leading economic indicators. Compared with other indicators, real M3 growth does not provide much information about future recessions, whilst movements in the All‐Share index provide information for up to 12 months but do not do better than the yield curve. The index of leading economic indicators outperforms the yield spread in the short run up to 4 months but the yield spread performs better at longer horizons.
- Full Text:
- Date Issued: 2007
Lessons from the dead masters: Wordsworth and Byron in J. M. Coetzee's Disgrace
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
- Authors: Beard, Margot
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6114 , http://hdl.handle.net/10962/d1003827
- Description: As one whose research interests lie in the field of Romanticism, most specifically Wordsworth and Byron, I was obviously intrigued by J. M. Coetzee's use of these poets in Disgrace. Subsequent readings of the work have convinced me that more attention needs to be paid to the deeper implications of their presence in the text. Certainly many scholars have explored the significance of David Lurie's professional interest in the Romantic poets and the novel's imbeddedness in what Jane Taylor has referred to as "the European Enlightenment's legacy of the autonomy of the individual" as well as a specifically "eighteenth century model of philosophical sympathy" (1999, 25). Yet I feel that insufficient attention has been paid to the significance of Romanticism, the Wordsworthian and the Byronic in the novel. Generally, the commentary ranges from seeing Lurie's academic interests as symptomatic of his white colonialist mentality to a more nuanced but insufficiently developed focus on the possibilities lying behind Coetzee's startling juxtaposition of two of the most famed and yet most overtly antagonistic of the Romantic poets. Zoë Wicomb is representative of the first approach. In her estimation, Lurie may be rejected since he "looks to Europe as the centre of reference" and "our feelings and experiences of nature need not be structured by poetic discourses from the metropolis".
- Full Text:
- Date Issued: 2007
Signatures of seaway closures and founder dispersal in the phylogeny of a circumglobally distributed seahorse lineage
- Teske, Peter R, Hamilton, Healy, Matthee, Conrad A, Barker, Nigel P
- Authors: Teske, Peter R , Hamilton, Healy , Matthee, Conrad A , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6549 , http://hdl.handle.net/10962/d1006005
- Description: The importance of vicariance events on the establishment of phylogeographic patterns in the marine environment is well documented, and generally accepted as an important cause of cladogenesis. Founder dispersal (i.e. long-distance dispersal followed by founder effect speciation) is also frequently invoked as a cause of genetic divergence among lineages, but its role has long been challenged by vicariance biogeographers. Founder dispersal is likely to be common in species that colonize remote habitats by means of rafting (e.g. seahorses), as long-distance dispersal events are likely to be rare and subsequent additional recruitment from the source habitat is unlikely. In the present study, the relative importance of vicariance and founder dispersal as causes of cladogenesis in a circumglobally distributed seahorse lineage was investigated using molecular dating. A phylogeny was reconstructed using sequence data from mitochondrial and nuclear markers, and the well-documented closure of the Central American seaway was used as a primary calibration point to test whether other bifurcations in the phylogeny could also have been the result of vicariance events. The feasibility of three other vicariance events was explored: a) the closure of the Indonesian Seaway, resulting in sister lineages associated with the Indian Ocean and West Pacific, respectively; b) the closure of the Tethyan Seaway, resulting in sister lineages associated with the Indo-Pacific and Atlantic Ocean, respectively, and c) continental break-up during the Mesozoic followed by spreading of the Atlantic Ocean, resulting in pairs of lineages with amphi-Atlantic distribution patterns.
- Full Text:
- Date Issued: 2007
- Authors: Teske, Peter R , Hamilton, Healy , Matthee, Conrad A , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6549 , http://hdl.handle.net/10962/d1006005
- Description: The importance of vicariance events on the establishment of phylogeographic patterns in the marine environment is well documented, and generally accepted as an important cause of cladogenesis. Founder dispersal (i.e. long-distance dispersal followed by founder effect speciation) is also frequently invoked as a cause of genetic divergence among lineages, but its role has long been challenged by vicariance biogeographers. Founder dispersal is likely to be common in species that colonize remote habitats by means of rafting (e.g. seahorses), as long-distance dispersal events are likely to be rare and subsequent additional recruitment from the source habitat is unlikely. In the present study, the relative importance of vicariance and founder dispersal as causes of cladogenesis in a circumglobally distributed seahorse lineage was investigated using molecular dating. A phylogeny was reconstructed using sequence data from mitochondrial and nuclear markers, and the well-documented closure of the Central American seaway was used as a primary calibration point to test whether other bifurcations in the phylogeny could also have been the result of vicariance events. The feasibility of three other vicariance events was explored: a) the closure of the Indonesian Seaway, resulting in sister lineages associated with the Indian Ocean and West Pacific, respectively; b) the closure of the Tethyan Seaway, resulting in sister lineages associated with the Indo-Pacific and Atlantic Ocean, respectively, and c) continental break-up during the Mesozoic followed by spreading of the Atlantic Ocean, resulting in pairs of lineages with amphi-Atlantic distribution patterns.
- Full Text:
- Date Issued: 2007
Stratigraphic correlation of the Awahab and Tafelberg Formations, Etendeka Group, Namibia, and location of an eruptive site for flood basalt volcanism
- Marsh, Julian S, Milner, Simon C
- Authors: Marsh, Julian S , Milner, Simon C
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6738 , http://hdl.handle.net/10962/d1007552 , http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
- Description: Detailed field and geochemical investigations in the vicinity of the type section of the Tafelberg Formation of the early Cretaceous Etendeka Group, NW Namibia, have revealed the existence of a large eruptive vent in the lower part of the regional volcanic sequence produced by Strombolian and Vulcanian eruptions. The vent is filled with the thick, differentiated, ponded Kudu-Run olivine-rich basaltic flow, which has a distinctive low Zr/Y geochemical signature as well as a Tafelberg-type tabular basalt and the Nil Desperandum latite. Field evidence indicates that the Kudu-Run basalt and the latite were erupted from fissures located within the vent. Associated with the vent is an extensive pyroclastic apron extending from the vent edge and which is interbedded with the regional stratigraphy. Blocks of Precambrain basement lithologies occur within this deposit and indicate that the vent was excavated to a depth of at least 350 m below the palaeosurface at that time. The original Tafelberg Formation type section described by Erlank et al. [Erlank, A.J., Marsh, J.S., Duncan, A.R., Miller, R.McG., Hawkesworth, C.H., Betton, P.J., Rex, D.C. 1984. Geochemistry and petrogenesis of the Etendeka volcanic rocks from SWA/Namibia, 195–247. In: Erlank, A.J. (Ed.), Petrogenesis of Volcanic Rocks of the Karoo province. Special Publication of the Geological Society of South Africa, vol. 13, 395 p.] the Tafelberg Gully section, crosses from the lower part of the regional sequence into the intra-vent sequence and returns to the regional sequence higher up. In doing so it includes some of the localized intra-vent flows and excludes a number of flows which are part of the regional sequence in its lower part, thus rendering it inappropriate as a type section. A revised type section for the Tafelberg Formation is described by combining the upper part of the Tafelberg Gully section with a new section of 14 flows at the base of the regional sequence in the Tafelberg North (TBN) section some 2 km N of the Tafeleberg Gully. Distinctive flows in the TBN section can be mapped southwards where their precise stratigraphic relationship to the northward-thinning Springbok and Goboboseb Quarts Latite members of the Awahab Formation can be demonstrated. These stratigraphic relationships are entirely consistent with palaeomagnetic reversal stratigraphy and demonstrate that the same N–R–N polarity sequence occurs in the type sections of the Awahab and Tafelberg formations. Thus, the Awahab and Tafelberg magma systems were contemporaneous but the Tafelberg system outlived that of the Awahab. The Awahab system was built from eruptive centres located S of the Huab River whereas the Tafelberg vents were located further north. , Full text article access in Journal of African Earth Sciences, 48 (5). pp. 329-340. Available: http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
- Full Text: false
- Date Issued: 2007
- Authors: Marsh, Julian S , Milner, Simon C
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6738 , http://hdl.handle.net/10962/d1007552 , http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
- Description: Detailed field and geochemical investigations in the vicinity of the type section of the Tafelberg Formation of the early Cretaceous Etendeka Group, NW Namibia, have revealed the existence of a large eruptive vent in the lower part of the regional volcanic sequence produced by Strombolian and Vulcanian eruptions. The vent is filled with the thick, differentiated, ponded Kudu-Run olivine-rich basaltic flow, which has a distinctive low Zr/Y geochemical signature as well as a Tafelberg-type tabular basalt and the Nil Desperandum latite. Field evidence indicates that the Kudu-Run basalt and the latite were erupted from fissures located within the vent. Associated with the vent is an extensive pyroclastic apron extending from the vent edge and which is interbedded with the regional stratigraphy. Blocks of Precambrain basement lithologies occur within this deposit and indicate that the vent was excavated to a depth of at least 350 m below the palaeosurface at that time. The original Tafelberg Formation type section described by Erlank et al. [Erlank, A.J., Marsh, J.S., Duncan, A.R., Miller, R.McG., Hawkesworth, C.H., Betton, P.J., Rex, D.C. 1984. Geochemistry and petrogenesis of the Etendeka volcanic rocks from SWA/Namibia, 195–247. In: Erlank, A.J. (Ed.), Petrogenesis of Volcanic Rocks of the Karoo province. Special Publication of the Geological Society of South Africa, vol. 13, 395 p.] the Tafelberg Gully section, crosses from the lower part of the regional sequence into the intra-vent sequence and returns to the regional sequence higher up. In doing so it includes some of the localized intra-vent flows and excludes a number of flows which are part of the regional sequence in its lower part, thus rendering it inappropriate as a type section. A revised type section for the Tafelberg Formation is described by combining the upper part of the Tafelberg Gully section with a new section of 14 flows at the base of the regional sequence in the Tafelberg North (TBN) section some 2 km N of the Tafeleberg Gully. Distinctive flows in the TBN section can be mapped southwards where their precise stratigraphic relationship to the northward-thinning Springbok and Goboboseb Quarts Latite members of the Awahab Formation can be demonstrated. These stratigraphic relationships are entirely consistent with palaeomagnetic reversal stratigraphy and demonstrate that the same N–R–N polarity sequence occurs in the type sections of the Awahab and Tafelberg formations. Thus, the Awahab and Tafelberg magma systems were contemporaneous but the Tafelberg system outlived that of the Awahab. The Awahab system was built from eruptive centres located S of the Huab River whereas the Tafelberg vents were located further north. , Full text article access in Journal of African Earth Sciences, 48 (5). pp. 329-340. Available: http://dx.doi.org/10.1016/j.jafrearsci.2007.04.004
- Full Text: false
- Date Issued: 2007
The effect of sulfide on -glucosidases: implications for starch degradation in anaerobic bioreactors
- Authors: Wutor, V C , Togo, C A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6463 , http://hdl.handle.net/10962/d1005792 , dx.doi.org/10.1016/j.chemosphere.2006.03.011
- Description: Membrane associated α-glucosidase activity was investigated in a methanogenic bioreactor (MR) and a biosulfidogenic bioreactor (SR). Temperature and pH optima studies showed temperature optima of 50 °C and pH optima of 8.0 for the α-glucosidases from both the MR and SR. Sulfide (at a concentration of 150 mg l[superscript (−1)]) resulted in the complete loss of all α-glucosidase activity in both the MR and SR. β-Glucosidase activities in our bioreactors were previously shown to be stimulated in the presence of sulfide. α-Glucosidases, in contrast, are inhibited by sulfide. This differential effect of sulfide on α-glucosidase and β-glucosidase activities is highlighted and is of crucial consequence to the respective degradation and utilization of starch and cellulose substrates in natural anaerobic environments and anaerobic bioreactors specifically designed for the accelerated digestion of wastewater sludge under biosulfidogenic conditions.
- Full Text:
- Date Issued: 2007
The effect of sulfide on -glucosidases: implications for starch degradation in anaerobic bioreactors
- Authors: Wutor, V C , Togo, C A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6463 , http://hdl.handle.net/10962/d1005792 , dx.doi.org/10.1016/j.chemosphere.2006.03.011
- Description: Membrane associated α-glucosidase activity was investigated in a methanogenic bioreactor (MR) and a biosulfidogenic bioreactor (SR). Temperature and pH optima studies showed temperature optima of 50 °C and pH optima of 8.0 for the α-glucosidases from both the MR and SR. Sulfide (at a concentration of 150 mg l[superscript (−1)]) resulted in the complete loss of all α-glucosidase activity in both the MR and SR. β-Glucosidase activities in our bioreactors were previously shown to be stimulated in the presence of sulfide. α-Glucosidases, in contrast, are inhibited by sulfide. This differential effect of sulfide on α-glucosidase and β-glucosidase activities is highlighted and is of crucial consequence to the respective degradation and utilization of starch and cellulose substrates in natural anaerobic environments and anaerobic bioreactors specifically designed for the accelerated digestion of wastewater sludge under biosulfidogenic conditions.
- Full Text:
- Date Issued: 2007
The humanities, vocationalism and the public good: exploring 'the Hamlet factor'
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
- Full Text:
- Date Issued: 2007
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7028 , http://hdl.handle.net/10962/d1007214 , https://doi.org/10.1080/17535360712331393503
- Description: preprint , This paper argues that the social mission of the humanities is no longer well understood by the public, sometimes not even by the very institutions seeking to attract students to these disciplines, the universities. It becomes difficult to argue for the cogency of research in the humanities, let alone for a specific national research agenda, when the general relation between the humanities and society is widely mistaken. To address such misapprehensions, the discussion outlines as clearly as possible the characteristic procedures of the humanities, the manner in which they inform individual and social transformation, and the contemporary predicament which makes them more rather than less needed in society’s repertoire of educational resources. With this understanding in place, the paper then puts forward suggestions for strengthening research in the humanities as part of a broader programme to renovate the humanities in the South African education system.
- Full Text:
- Date Issued: 2007
Time-resolved luminescence of low sensitivity quartz from crystalline rocks
- Chithambo, Makaiko L, Preusser, F, Ramseyer, K, Ogundare, F O
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
- Full Text:
- Date Issued: 2007
- Authors: Chithambo, Makaiko L , Preusser, F , Ramseyer, K , Ogundare, F O
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:6801 , http://hdl.handle.net/10962/d1004164 , https://doi.org/10.1016/j.radmeas.2006.07.005
- Description: preprint , Time-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center.
- Full Text:
- Date Issued: 2007
Indigenous languages and the media in South Africa:
- Authors: Kaschula, Russell H
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175137 , vital:42546 , https://hdl.handle.net/10520/EJC15168
- Description: This article explores the status of South Africa’s indigenous languages and how they are being used in the media. More specifically, the performance of these languages in the print media, the broadcasting media and the Internet, is outlined. This is done against the backdrop of the South African Constitution, Section 6, which entrenches eleven official languages. Contrary to the Constitution’s provisions, it is found that the indigenous languages are achieving varying levels of success within the media. The reasons for this are outlined. Finally, the effects of globalisation on the indigenous languages within the media are assessed.
- Full Text:
- Date Issued: 2006
- Authors: Kaschula, Russell H
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/175137 , vital:42546 , https://hdl.handle.net/10520/EJC15168
- Description: This article explores the status of South Africa’s indigenous languages and how they are being used in the media. More specifically, the performance of these languages in the print media, the broadcasting media and the Internet, is outlined. This is done against the backdrop of the South African Constitution, Section 6, which entrenches eleven official languages. Contrary to the Constitution’s provisions, it is found that the indigenous languages are achieving varying levels of success within the media. The reasons for this are outlined. Finally, the effects of globalisation on the indigenous languages within the media are assessed.
- Full Text:
- Date Issued: 2006
JM Coetzee's Disgrace and the Task of the Imagination:
- Authors: Marais, Mike
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144126 , vital:38313 , DOI: 10.2979/JML.2006.29.2.75
- Description: In an early review of Disgrace, Jane Taylor first relates this novel's treatment of violence in post-apartheid South Africa to the European Enlightenment's legacy of the autonomy of the human subject (25), in terms of which each individual is conceived of as a living consciousness separated totally from every other consciousness, and then discusses J.M. Coetzee's postulation of the sympathetic imagination as a potential corrective to the violence attendant on monadic individuality. Taylor makes the telling point that, in the eighteenth century, the notions of sensibility, sympathy, and compassion, which the novel repeatedly invokes, were self-consciously developed as an ethical response to the instrumentalist logic of autonomous individuality and, in this regard, she cites Adam Smith's observation in The Theory of Moral Sentiments that "By the imagination we place ourselves in his situation, we conceive ourselves enduring all the same torments, we enter as it were into his body, and become in some measure the same person with him, and thence form some idea of his sensation" (qtd. in Taylor 25).
- Full Text:
- Date Issued: 2006
- Authors: Marais, Mike
- Date: 2006
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144126 , vital:38313 , DOI: 10.2979/JML.2006.29.2.75
- Description: In an early review of Disgrace, Jane Taylor first relates this novel's treatment of violence in post-apartheid South Africa to the European Enlightenment's legacy of the autonomy of the human subject (25), in terms of which each individual is conceived of as a living consciousness separated totally from every other consciousness, and then discusses J.M. Coetzee's postulation of the sympathetic imagination as a potential corrective to the violence attendant on monadic individuality. Taylor makes the telling point that, in the eighteenth century, the notions of sensibility, sympathy, and compassion, which the novel repeatedly invokes, were self-consciously developed as an ethical response to the instrumentalist logic of autonomous individuality and, in this regard, she cites Adam Smith's observation in The Theory of Moral Sentiments that "By the imagination we place ourselves in his situation, we conceive ourselves enduring all the same torments, we enter as it were into his body, and become in some measure the same person with him, and thence form some idea of his sensation" (qtd. in Taylor 25).
- Full Text:
- Date Issued: 2006
New and improved : Linda in Java
- Authors: Wells, George C
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6613 , http://hdl.handle.net/10962/d1011511 , http://www.sciencedirect.com/science/article/pii/S0167642305000869
- Description: This paper discusses the current resurgence of interest in the Linda coordination language for parallel and distributed programming. Particularly in the Java field, there have been a number of developments over the past few years. These developments are summarised together with the advantages of using Linda for programming concurrent systems. Some problems with the basic Linda approach are also discussed and a novel solution to these is presented. The power and flexibility of the proposed extensions to the Linda programming model are illustrated by considering a number of example applications, including a detailed case study of visual language parsing.
- Full Text:
- Date Issued: 2006
- Authors: Wells, George C
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6613 , http://hdl.handle.net/10962/d1011511 , http://www.sciencedirect.com/science/article/pii/S0167642305000869
- Description: This paper discusses the current resurgence of interest in the Linda coordination language for parallel and distributed programming. Particularly in the Java field, there have been a number of developments over the past few years. These developments are summarised together with the advantages of using Linda for programming concurrent systems. Some problems with the basic Linda approach are also discussed and a novel solution to these is presented. The power and flexibility of the proposed extensions to the Linda programming model are illustrated by considering a number of example applications, including a detailed case study of visual language parsing.
- Full Text:
- Date Issued: 2006
On the fast track to land degradation? A case study of the impact of the Fast Track Land Reform Programme in Kadoma District, Zimbabwe
- Fox, Roddy C, Rowntree, Kate M, Chigumira, Easther C
- Authors: Fox, Roddy C , Rowntree, Kate M , Chigumira, Easther C
- Date: 2006
- Language: English
- Type: Conference paper
- Identifier: vital:6663 , http://hdl.handle.net/10962/d1006668
- Description: The Fast Track Land Reform Programme is the defining instrument for Zimbabwe’s future development prospects. In the three year period from 2000 to 2002 300,000 families were resettled on 11 million hectares thus witnessing the end of the colonial division of land which had seen 15.5 million hectares still in European hands in 1980, the start of the post-colonial period. The process which displaced the commercial farm workers and farm owners was chaotic, violent and disorderly and so has been called jambanja. Subsequent legislation and government agricultural initiatives have attempted to impose, retroactively, technocratic order to the sweeping changes that have taken place. Our study shows that the dire macro-economic situation coupled with trends of HIV/AIDS prevalence means that developing sustainable land use practices is going to be a very difficult proposition. At the local scale, our case studies show that there have been multiple outcomes with low investment, very limited government support and resource extraction leading to land degradation and unsustainable farming practices. In some instances, however, individual households have benefitted in the short term from the process but this has only occurred where climatic and soil conditions have been particularly favourable.
- Full Text:
- Date Issued: 2006
- Authors: Fox, Roddy C , Rowntree, Kate M , Chigumira, Easther C
- Date: 2006
- Language: English
- Type: Conference paper
- Identifier: vital:6663 , http://hdl.handle.net/10962/d1006668
- Description: The Fast Track Land Reform Programme is the defining instrument for Zimbabwe’s future development prospects. In the three year period from 2000 to 2002 300,000 families were resettled on 11 million hectares thus witnessing the end of the colonial division of land which had seen 15.5 million hectares still in European hands in 1980, the start of the post-colonial period. The process which displaced the commercial farm workers and farm owners was chaotic, violent and disorderly and so has been called jambanja. Subsequent legislation and government agricultural initiatives have attempted to impose, retroactively, technocratic order to the sweeping changes that have taken place. Our study shows that the dire macro-economic situation coupled with trends of HIV/AIDS prevalence means that developing sustainable land use practices is going to be a very difficult proposition. At the local scale, our case studies show that there have been multiple outcomes with low investment, very limited government support and resource extraction leading to land degradation and unsustainable farming practices. In some instances, however, individual households have benefitted in the short term from the process but this has only occurred where climatic and soil conditions have been particularly favourable.
- Full Text:
- Date Issued: 2006