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:
- Date Issued: 2007
- 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:
- Date Issued: 2007
The effect of temperature and salinity on oxygen consumption in the brachyuran crab Cyclograpsus punctatus (Crustacea: Decapoda: Grapsidae)
- Winch, James W W, Hodgson, Alan N
- Authors: Winch, James W W , Hodgson, Alan N
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447426 , vital:74624 , https://doi.org/10.1080/15627020.2007.11407384
- Description: The aquatic oxygen consumption of the estuarine brachyuran crab, Cyclograpsus punctatus, was investigated after a 24-hour acclimation period at different temperature (12.5, 20, 30°C) and salinity (9, 17.5, 35, and 44°) combinations . Salinity had no significant effect on oxygen consumption at 12.5 and 20°C in both large and small crabs. At 30°C and 44°, however, the rate of oxygen consumption declined in large crabs (from 0.233 to 0.176 mg O2 g wwt/h) and increased in small crabs (0.300 to 0.469 mg O2 g wwt/h). There was also a significant increase in the oxygen consumption (0.300 to 0.536 mg O2 g wwt/h) of small crabs at the high temperature/low salinity combination. Temperature had a significant effect on the rate of oxygen consumption at all salinities, with Q10 values ranging from 1.16 to 2.85. In all cases the mass-specific oxygen consumption rate of small crabs was higher than that of large crabs. The results suggest that the confinement of this species to the lower reaches of estuaries may, in part, be due to physiological constraints on juveniles and small individuals.
- Full Text:
- Date Issued: 2007
- Authors: Winch, James W W , Hodgson, Alan N
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447426 , vital:74624 , https://doi.org/10.1080/15627020.2007.11407384
- Description: The aquatic oxygen consumption of the estuarine brachyuran crab, Cyclograpsus punctatus, was investigated after a 24-hour acclimation period at different temperature (12.5, 20, 30°C) and salinity (9, 17.5, 35, and 44°) combinations . Salinity had no significant effect on oxygen consumption at 12.5 and 20°C in both large and small crabs. At 30°C and 44°, however, the rate of oxygen consumption declined in large crabs (from 0.233 to 0.176 mg O2 g wwt/h) and increased in small crabs (0.300 to 0.469 mg O2 g wwt/h). There was also a significant increase in the oxygen consumption (0.300 to 0.536 mg O2 g wwt/h) of small crabs at the high temperature/low salinity combination. Temperature had a significant effect on the rate of oxygen consumption at all salinities, with Q10 values ranging from 1.16 to 2.85. In all cases the mass-specific oxygen consumption rate of small crabs was higher than that of large crabs. The results suggest that the confinement of this species to the lower reaches of estuaries may, in part, be due to physiological constraints on juveniles and small individuals.
- Full Text:
- Date Issued: 2007
The effects of fire on post-fire seed germination of selected Savanna woody species
- Authors: Shackleton, Charlie M
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183104 , vital:43912 , xlink:href=" https://doi.org/10.1111/j.1365-2028.2007.00766.x"
- Description: Although fire is recognized as an integral component of savanna dynamics, there is a dearth of understanding of its impacts on woody plant seeds. This study examined the impacts of fire in stimulating or constraining post-fire germination of seven common savanna woody species. Seeds of two species (Combretum hereroense and Euclea natalensis) failed to germinate irrespective of fire treatment. For the remaining five species, fire effects were dependent on seed location as either on the soil surface or buried. For surface seeds, fire effects reduced germination in four of the species, and stimulated it for one species (Acacia swazica). For buried seeds, fire had no effect. A significant proportion of surface seeds were destroyed by fire, and overall germination was higher for buried seed for most species other than A. swazica.
- Full Text:
- Date Issued: 2007
- Authors: Shackleton, Charlie M
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183104 , vital:43912 , xlink:href=" https://doi.org/10.1111/j.1365-2028.2007.00766.x"
- Description: Although fire is recognized as an integral component of savanna dynamics, there is a dearth of understanding of its impacts on woody plant seeds. This study examined the impacts of fire in stimulating or constraining post-fire germination of seven common savanna woody species. Seeds of two species (Combretum hereroense and Euclea natalensis) failed to germinate irrespective of fire treatment. For the remaining five species, fire effects were dependent on seed location as either on the soil surface or buried. For surface seeds, fire effects reduced germination in four of the species, and stimulated it for one species (Acacia swazica). For buried seeds, fire had no effect. A significant proportion of surface seeds were destroyed by fire, and overall germination was higher for buried seed for most species other than A. swazica.
- Full Text:
- Date Issued: 2007
The habitus of the dominant: addressing rape and sexual assault at Rhodes University
- de Klerk, Vivian A, Klazinga, Larissa, McNeill, Amy
- Authors: de Klerk, Vivian A , Klazinga, Larissa , McNeill, Amy
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453352 , vital:75247 , https://doi.org/10.1080/10130950.2007.9674885
- Description: This article seeks to describe the changing ways in which Rhodes University has addressed rape and sexual assault. By highlighting the evolution of policies and methodologies, it aims to identify possible shortcomings of the past, and offer new strategies and principles which may be useful to fellow institutions grappling with sexual violence issues.
- Full Text:
- Date Issued: 2007
- Authors: de Klerk, Vivian A , Klazinga, Larissa , McNeill, Amy
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/453352 , vital:75247 , https://doi.org/10.1080/10130950.2007.9674885
- Description: This article seeks to describe the changing ways in which Rhodes University has addressed rape and sexual assault. By highlighting the evolution of policies and methodologies, it aims to identify possible shortcomings of the past, and offer new strategies and principles which may be useful to fellow institutions grappling with sexual violence issues.
- 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
The relationship between female pupal mass and fecundity of Gratiana spadicea (Klug, 1829)(Coleoptera: Chrysomelidae)
- Czypionka, K, Hill, Martin P
- Authors: Czypionka, K , Hill, Martin P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451568 , vital:75060 , https://hdl.handle.net/10520/EJC32729
- Description: In the early 1900s Solanum sisymbriifolium Lamarck (Solanaceae), commonly known as dense thorned bitter apple and previously referred to as wild tomato, was introduced into southern Africa and has since become an invasive weed (Hill and Hulley 1995, 1996). In 1994 a chrysomelid beetle, Gratiana spadicea (Klug, 1829) (Coleoptera : Chrysomelidae), was introduced as a biological control agent against the weed (Hill and Hulley 1995). Prior to its release, various specificity tests were conducted to identify the potential host range of this agent. These included larval survival and adult choice and no-choice tests on several native and commercial Solanum species. These specificity tests generally identify the potential host range of an agent accurately, but fail to predict the magnitude of non-target risks in the field (Wan and Harris 1997; Louda et al. 2003).
- Full Text:
- Date Issued: 2007
- Authors: Czypionka, K , Hill, Martin P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451568 , vital:75060 , https://hdl.handle.net/10520/EJC32729
- Description: In the early 1900s Solanum sisymbriifolium Lamarck (Solanaceae), commonly known as dense thorned bitter apple and previously referred to as wild tomato, was introduced into southern Africa and has since become an invasive weed (Hill and Hulley 1995, 1996). In 1994 a chrysomelid beetle, Gratiana spadicea (Klug, 1829) (Coleoptera : Chrysomelidae), was introduced as a biological control agent against the weed (Hill and Hulley 1995). Prior to its release, various specificity tests were conducted to identify the potential host range of this agent. These included larval survival and adult choice and no-choice tests on several native and commercial Solanum species. These specificity tests generally identify the potential host range of an agent accurately, but fail to predict the magnitude of non-target risks in the field (Wan and Harris 1997; Louda et al. 2003).
- Full Text:
- Date Issued: 2007
The status of the southern ground-hornbill in the Grahamstown region, Eastern Cape, South Africa
- Hulley, Patrick E, Craig, Adrian J F K
- Authors: Hulley, Patrick E , Craig, Adrian J F K
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447909 , vital:74683 , https://www.tandfonline.com/doi/pdf/10.2989/OSTRICH.2007.78.1.13.57
- Description: The Eastern Cape has been the southernmost limit of distribution for the Southern Ground-Hornbill Bucorvus leadbeateri throughout the period for which there are written records (Vernon 1986, Vernon and Herremans 1997). No records are known west of Port Elizabeth and the only ones from this 1 map square (33 S 27 E) date from the nineteenth century. Vernon (1986) noted that nest and roost sites for groundhornbills were in large trees or on cliffs, from which the birds commuted to forage in open country. The forest/thicket and grassland mosaic in the Eastern Cape is apparently ancient (Skead 1987), but the grassland sector has been greatly modified by agriculture and human settlement. Since the assessment of the Southern Ground-Hornbill’s status as ‘vulnerable’in the latest Red Data Book (Barnes 2000), it has been suggested that populations in South Africa have declined to a point where its true status is ‘endangered’but this revision was not accepted by IUCN (AC Kemp, pers. comm.). The recent initiative by the Mabula-based NGO, the Ground-hornbill Research and Conservation Project, to reintroduce birds to the Eastern Cape, prompted us to examine records of sightings in this region. The main focus is the Grahamstown map square 33 S 26 E, in which the release site of the first birds—Shamwari Private Game Reserve—is situated. Our source is the published records in Diaz Diary, the newsletter of the Diaz Cross Bird Club, which has branches in Grahamstown and Kenton-on-Sea, covering the period 1978–2004 inclusive.
- Full Text:
- Date Issued: 2007
- Authors: Hulley, Patrick E , Craig, Adrian J F K
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447909 , vital:74683 , https://www.tandfonline.com/doi/pdf/10.2989/OSTRICH.2007.78.1.13.57
- Description: The Eastern Cape has been the southernmost limit of distribution for the Southern Ground-Hornbill Bucorvus leadbeateri throughout the period for which there are written records (Vernon 1986, Vernon and Herremans 1997). No records are known west of Port Elizabeth and the only ones from this 1 map square (33 S 27 E) date from the nineteenth century. Vernon (1986) noted that nest and roost sites for groundhornbills were in large trees or on cliffs, from which the birds commuted to forage in open country. The forest/thicket and grassland mosaic in the Eastern Cape is apparently ancient (Skead 1987), but the grassland sector has been greatly modified by agriculture and human settlement. Since the assessment of the Southern Ground-Hornbill’s status as ‘vulnerable’in the latest Red Data Book (Barnes 2000), it has been suggested that populations in South Africa have declined to a point where its true status is ‘endangered’but this revision was not accepted by IUCN (AC Kemp, pers. comm.). The recent initiative by the Mabula-based NGO, the Ground-hornbill Research and Conservation Project, to reintroduce birds to the Eastern Cape, prompted us to examine records of sightings in this region. The main focus is the Grahamstown map square 33 S 26 E, in which the release site of the first birds—Shamwari Private Game Reserve—is situated. Our source is the published records in Diaz Diary, the newsletter of the Diaz Cross Bird Club, which has branches in Grahamstown and Kenton-on-Sea, covering the period 1978–2004 inclusive.
- Full Text:
- Date Issued: 2007
The synthesis, fluorescence behaviour and singlet oxygen studies of new water-soluble cationic gallium (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/10962/280207 , vital:55586 , xlink:href="https://doi.org/10.1016/j.inoche.2006.11.012"
- Description: The preparation of cationic water-soluble gallium phthalocyanine derivatives are described for the first time. Peripheral and non-peripheral 3-hydroxypyridine tetrasubstituted gallium(III)phthalocyanines (5a, 6a) and their quaternarized derivatives (5b and 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b and 6b) are soluble in water and not aggregated (in water and in organic solvents) within a wide concentration range. General trends are described for singlet oxygen quantum yields, fluorescence quantum yields and fluorescence lifetimes of these compounds. These complexes showed better singlet oxygen quantum yields in water than the related quarternarized porphyrazine complexes.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/280207 , vital:55586 , xlink:href="https://doi.org/10.1016/j.inoche.2006.11.012"
- Description: The preparation of cationic water-soluble gallium phthalocyanine derivatives are described for the first time. Peripheral and non-peripheral 3-hydroxypyridine tetrasubstituted gallium(III)phthalocyanines (5a, 6a) and their quaternarized derivatives (5b and 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b and 6b) are soluble in water and not aggregated (in water and in organic solvents) within a wide concentration range. General trends are described for singlet oxygen quantum yields, fluorescence quantum yields and fluorescence lifetimes of these compounds. These complexes showed better singlet oxygen quantum yields in water than the related quarternarized porphyrazine complexes.
- Full Text:
- Date Issued: 2007
The thirtieth anniversary of the Soweto uprisings: reading the shadow in Sam Nzima's iconic photograph of Hector Pieterson
- Authors: Simbao, Ruth K
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147536 , vital:38647 , https://doi.org/10.1162/afar.2007.40.2.52
- Description: This haunting photograph (Fig. 1) from the 1976 Soweto Uprisings in South Africa is often referred to as the single most important photograph to emerge from the struggle against apartheid (Purtilo 1999:22). According to South African film director Feizel Mamdoo, there are particular moments in history that are defined by photographic, celluloid, or television images, such as the world famous photograph of the Saigon girl, naked and burning from napalm (Worsdale 1998; see also Richards 2001). He argues that the iconic photograph by Sam Nzima depicting Hector Pieterson being carried in the arms of Mbuyisa Makhubu, with his distraught sister Antionette1 running alongside, is comparable in the way that “it marks history, both social and personal” (Worsdale 1998).
- Full Text:
- Date Issued: 2007
- Authors: Simbao, Ruth K
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147536 , vital:38647 , https://doi.org/10.1162/afar.2007.40.2.52
- Description: This haunting photograph (Fig. 1) from the 1976 Soweto Uprisings in South Africa is often referred to as the single most important photograph to emerge from the struggle against apartheid (Purtilo 1999:22). According to South African film director Feizel Mamdoo, there are particular moments in history that are defined by photographic, celluloid, or television images, such as the world famous photograph of the Saigon girl, naked and burning from napalm (Worsdale 1998; see also Richards 2001). He argues that the iconic photograph by Sam Nzima depicting Hector Pieterson being carried in the arms of Mbuyisa Makhubu, with his distraught sister Antionette1 running alongside, is comparable in the way that “it marks history, both social and personal” (Worsdale 1998).
- Full Text:
- Date Issued: 2007
Think Piece : an opening dialogue with Think Pieces and feature articles on learning in a changing world in this journal
- Authors: Lotz-Sisitka, Heila
- Date: 2007
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59602 , vital:27630 , https://www.ajol.info/index.php/sajee/article/view/122734
- Description: From Conclusion:This opening Think Piece invites you into such a dialogue, with this journal, its words and flows of meaning, and with the World Environmental Education Congress, its words and flows of meaning. Dialogue, as explained by Bohm, and as illustrated in the thought experiments in this paper, is a process of creatively and experimentally seeking out meaning and coherence through listening, and through deeper explorations of the tacit, implicate order. It is also a free process, where you as individual are invited to seek out the relations between your thoughts and the collective. Welcome to the process.
- Full Text:
- Date Issued: 2007
- Authors: Lotz-Sisitka, Heila
- Date: 2007
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59602 , vital:27630 , https://www.ajol.info/index.php/sajee/article/view/122734
- Description: From Conclusion:This opening Think Piece invites you into such a dialogue, with this journal, its words and flows of meaning, and with the World Environmental Education Congress, its words and flows of meaning. Dialogue, as explained by Bohm, and as illustrated in the thought experiments in this paper, is a process of creatively and experimentally seeking out meaning and coherence through listening, and through deeper explorations of the tacit, implicate order. It is also a free process, where you as individual are invited to seek out the relations between your thoughts and the collective. Welcome to the process.
- Full Text:
- Date Issued: 2007
Thiol oxidation at 2-mercaptopyrimidine-appended cobalt phthalocyanine modified glassy carbon electrodes
- Obirai, Joseph C, Nyokong, Tebello
- Authors: Obirai, Joseph C , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281403 , vital:55722 , xlink:href="https://doi.org/10.1016/j.jelechem.2006.10.033"
- Description: The electrocatalytic activity of cobalt tetra-2-mercaptopyrimidylphthalocyanine-modified glassy carbon electrode (CoTMPyrPc-GCE) toward gluthathione, L-cysteine and 2-mercaptoethanol has been investigated. CoTMPyrPc-GCE provides a significant improvement on the reported oxidation potential of L-cysteine in pH 4.0 phosphate buffered solution. The oxidation peak potential (Ep), for L-cysteine, was 0.15 V – a relatively lowered oxidation potential compared to reported phthalocyanine complexes. The electrode prepared by drop-dry/thermal annealing method was very stable and sensitive over a long period of time. The stability has been attributed to the thermal annealing and the structure of the mercaptopyrimidine on the periphery of the CoPc.
- Full Text:
- Date Issued: 2007
- Authors: Obirai, Joseph C , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281403 , vital:55722 , xlink:href="https://doi.org/10.1016/j.jelechem.2006.10.033"
- Description: The electrocatalytic activity of cobalt tetra-2-mercaptopyrimidylphthalocyanine-modified glassy carbon electrode (CoTMPyrPc-GCE) toward gluthathione, L-cysteine and 2-mercaptoethanol has been investigated. CoTMPyrPc-GCE provides a significant improvement on the reported oxidation potential of L-cysteine in pH 4.0 phosphate buffered solution. The oxidation peak potential (Ep), for L-cysteine, was 0.15 V – a relatively lowered oxidation potential compared to reported phthalocyanine complexes. The electrode prepared by drop-dry/thermal annealing method was very stable and sensitive over a long period of time. The stability has been attributed to the thermal annealing and the structure of the mercaptopyrimidine on the periphery of the CoPc.
- 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
Towards continental transformation: understanding sustainable peace agreements in Africa
- Authors: Bischoff, Paul, 1954-
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161409 , vital:40624 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC15983
- Description: There are social and political questions to be asked about the new continent-wide institutions in and around what is still a young African Union (AU). These include questions such as whether the AU and its institutions can be built in ways that will allow this body to transform Africa's international relations, and how this is to be done. What are the norms and values that will inform this change and the African renewal promoted by the AU? Is the multilateral architecture of the AU able to encourage democracy and people-centredness, for instance? Will it, in the end, be able to deliver on the hoped-for "pan-African transnational democratic revolution"?.
- Full Text:
- Date Issued: 2007
- Authors: Bischoff, Paul, 1954-
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/161409 , vital:40624 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC15983
- Description: There are social and political questions to be asked about the new continent-wide institutions in and around what is still a young African Union (AU). These include questions such as whether the AU and its institutions can be built in ways that will allow this body to transform Africa's international relations, and how this is to be done. What are the norms and values that will inform this change and the African renewal promoted by the AU? Is the multilateral architecture of the AU able to encourage democracy and people-centredness, for instance? Will it, in the end, be able to deliver on the hoped-for "pan-African transnational democratic revolution"?.
- Full Text:
- Date Issued: 2007
Transformations of manool. Tri-and tetracyclic norditerpenoids with in vitro activity against plasmodium falciparum
- van Wyk, Albert W W, Lobb, Kevin A, Mino, Caira R, Hoppe, Heinrich C, Davies-Coleman, Michael T
- Authors: van Wyk, Albert W W , Lobb, Kevin A , Mino, Caira R , Hoppe, Heinrich C , Davies-Coleman, Michael T
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450511 , vital:74956 , xlink:href="https://doi.org/10.1021/np0701071"
- Description: The known 17-norisopimar-15-ene-8‚,13‚-diol (5) and five new semisynthetic norditerpenoids, ethyl 17-norabiet-13-(15)-E-en-8‚-ol-16-oate (6), ethyl 17-norabiet-13(15)-Z-en-8‚-ol-16-oate (7), 17-norpimaran-13R-ethoxy-8,16-olactone(8), 17-norisopimarane-8‚,15-diol (9), and 17-norarabiet-13(15)-ene-8‚,16-diol (10), were prepared from manool (11).Standard spectroscopic data including X-ray crystal analysis were used to determine the structures of5-10. All fivecompounds exhibited in Vitroantiplasmodial activity against the malarial parasitePlasmodium falciparumat varyingÌgmL-1concentrations.
- Full Text:
- Date Issued: 2007
- Authors: van Wyk, Albert W W , Lobb, Kevin A , Mino, Caira R , Hoppe, Heinrich C , Davies-Coleman, Michael T
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450511 , vital:74956 , xlink:href="https://doi.org/10.1021/np0701071"
- Description: The known 17-norisopimar-15-ene-8‚,13‚-diol (5) and five new semisynthetic norditerpenoids, ethyl 17-norabiet-13-(15)-E-en-8‚-ol-16-oate (6), ethyl 17-norabiet-13(15)-Z-en-8‚-ol-16-oate (7), 17-norpimaran-13R-ethoxy-8,16-olactone(8), 17-norisopimarane-8‚,15-diol (9), and 17-norarabiet-13(15)-ene-8‚,16-diol (10), were prepared from manool (11).Standard spectroscopic data including X-ray crystal analysis were used to determine the structures of5-10. All fivecompounds exhibited in Vitroantiplasmodial activity against the malarial parasitePlasmodium falciparumat varyingÌgmL-1concentrations.
- Full Text:
- Date Issued: 2007
Transforming the media: a cultural approach
- Authors: Steenveld, Lynette N
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147891 , vital:38682 , DOI: 10.1080/02560240485310061
- Description: The change from an Apartheid state to a liberal democratic one has wrought many changes at all levels of South African society: the economic, social, political, cultural. This paper explores the impacts of these changes on the South African print media industry, with a view to assessing their contribution to the development of a democratic citizenship. While acknowledging the constraining effects of economic structures of ownership, the paper locates these within the broader social and political context of post-apartheid South Africa. It thus attempts to synthesise elements of both a political economy and cultural approach to the analysis of cultural production.
- Full Text:
- Date Issued: 2007
- Authors: Steenveld, Lynette N
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147891 , vital:38682 , DOI: 10.1080/02560240485310061
- Description: The change from an Apartheid state to a liberal democratic one has wrought many changes at all levels of South African society: the economic, social, political, cultural. This paper explores the impacts of these changes on the South African print media industry, with a view to assessing their contribution to the development of a democratic citizenship. While acknowledging the constraining effects of economic structures of ownership, the paper locates these within the broader social and political context of post-apartheid South Africa. It thus attempts to synthesise elements of both a political economy and cultural approach to the analysis of cultural production.
- Full Text:
- Date Issued: 2007
Translation processes in the design of an education for sustainable development innovations course for universities in Africa
- Lotz-Sisitka, Heila, Lupele, Justin, Ogbuigwe, Akpezi
- Authors: Lotz-Sisitka, Heila , Lupele, Justin , Ogbuigwe, Akpezi
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127213 , vital:35978 , https://10.1080/02607470701259440
- Description: This paper traces the translation processes associated with the mobilization of resources and human agency in the development of a United Nations Environment Programme (UNEP) Education for Sustainable Development (ESD) Innovations Course for universities in Africa. University teachers are often neglected in teacher education initiatives. There are few formal professional development opportunities available for university teachers given the traditionally established hierarchy in the higher education sector as university teachers are normally the ones offering professional development to others. The paper explores how a participatory, deliberative translation process has served to provide professional development and professional exchange opportunities for university teachers which are non‐traditional and responsive to diversity, history, context and risk. The emergence of the modern African university is essentially a post‐independence (post‐1960s) phenomenon, with a few earlier African universities being colonially structured, controlled and inspired. Through a short historical overview, we introduce the African university landscape and some of its contemporary contextual and educational challenges. We then describe the process of deliberation that took place amongst university teachers from 23 African countries to initiate and establish the ESD Innovations Course. The paper concludes by arguing for open and participatory approaches in ESD teacher education course design, if we are to support university teachers (including teacher educators) to engage in mainstreaming environment and sustainability questions in higher education. The paper draws on the translation model provided by Latour in his actor network theory to describe and explain the deliberative translation process in the UNEP ESD Innovations Course. In doing this, it illuminates the possibilities of such a deliberative translation process for university teacher education. It also points to limitations encountered in applying this framework to this analysis, opening new vantage points for research of this nature in teacher education.
- Full Text:
- Date Issued: 2007
- Authors: Lotz-Sisitka, Heila , Lupele, Justin , Ogbuigwe, Akpezi
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127213 , vital:35978 , https://10.1080/02607470701259440
- Description: This paper traces the translation processes associated with the mobilization of resources and human agency in the development of a United Nations Environment Programme (UNEP) Education for Sustainable Development (ESD) Innovations Course for universities in Africa. University teachers are often neglected in teacher education initiatives. There are few formal professional development opportunities available for university teachers given the traditionally established hierarchy in the higher education sector as university teachers are normally the ones offering professional development to others. The paper explores how a participatory, deliberative translation process has served to provide professional development and professional exchange opportunities for university teachers which are non‐traditional and responsive to diversity, history, context and risk. The emergence of the modern African university is essentially a post‐independence (post‐1960s) phenomenon, with a few earlier African universities being colonially structured, controlled and inspired. Through a short historical overview, we introduce the African university landscape and some of its contemporary contextual and educational challenges. We then describe the process of deliberation that took place amongst university teachers from 23 African countries to initiate and establish the ESD Innovations Course. The paper concludes by arguing for open and participatory approaches in ESD teacher education course design, if we are to support university teachers (including teacher educators) to engage in mainstreaming environment and sustainability questions in higher education. The paper draws on the translation model provided by Latour in his actor network theory to describe and explain the deliberative translation process in the UNEP ESD Innovations Course. In doing this, it illuminates the possibilities of such a deliberative translation process for university teacher education. It also points to limitations encountered in applying this framework to this analysis, opening new vantage points for research of this nature in teacher education.
- Full Text:
- Date Issued: 2007
Tuning the redox properties of metalloporphyrin-and metallophthalocyanine-based molecular electrodes for the highest electrocatalytic activity in the oxidation of thiols
- Bedioui, Fethi, Griveau, Sophie, Nyokong, Tebello, Appleby, A John, Caro, Claudia A, Gulppi, Miguel, Ochoa, Gonzalo, Zagal, José H
- Authors: Bedioui, Fethi , Griveau, Sophie , Nyokong, Tebello , Appleby, A John , Caro, Claudia A , Gulppi, Miguel , Ochoa, Gonzalo , Zagal, José H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283988 , vital:56009 , xlink:href="https://doi.org/10.1039/B618767F"
- Description: In this work we discuss different approaches for achieving electrodes modified with N4 macrocyclic complexes for the catalysis of the electrochemical oxidation of thiols. These approaches involve adsorption, electropolymerization and molecular anchoring using self assembled monolayers. We also discuss the parameters that determine the reactivity of these complexes. Catalytic activity is associated with the nature of the central metal, redox potentials and Hammett parameters of substituents on the ligand. Correlations between catalytic activity (log i at constant E) and the redox potential of catalysts for complexes of Cr, Mn, Fe, Co, Ni and Cu are linear with an increase of activity for more positive redox potentials. For a great variety complexes bearing the same metal center (Co) correlations between log i and Eo′ of the Co(II)/Co(I) couple have the shape of an unsymmetric volcano. This indicates that the potential of the Co(II)/Co(I) couple can be tuned using the appropiate ligand to achieve maximum catalytic activity. Maximum activity probably corresponds to a ΔG of adsorption of the thiol on the Co center equal to zero, and to a coverage of active sites by the thiol equal to 0.5.
- Full Text:
- Date Issued: 2007
- Authors: Bedioui, Fethi , Griveau, Sophie , Nyokong, Tebello , Appleby, A John , Caro, Claudia A , Gulppi, Miguel , Ochoa, Gonzalo , Zagal, José H
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283988 , vital:56009 , xlink:href="https://doi.org/10.1039/B618767F"
- Description: In this work we discuss different approaches for achieving electrodes modified with N4 macrocyclic complexes for the catalysis of the electrochemical oxidation of thiols. These approaches involve adsorption, electropolymerization and molecular anchoring using self assembled monolayers. We also discuss the parameters that determine the reactivity of these complexes. Catalytic activity is associated with the nature of the central metal, redox potentials and Hammett parameters of substituents on the ligand. Correlations between catalytic activity (log i at constant E) and the redox potential of catalysts for complexes of Cr, Mn, Fe, Co, Ni and Cu are linear with an increase of activity for more positive redox potentials. For a great variety complexes bearing the same metal center (Co) correlations between log i and Eo′ of the Co(II)/Co(I) couple have the shape of an unsymmetric volcano. This indicates that the potential of the Co(II)/Co(I) couple can be tuned using the appropiate ligand to achieve maximum catalytic activity. Maximum activity probably corresponds to a ΔG of adsorption of the thiol on the Co center equal to zero, and to a coverage of active sites by the thiol equal to 0.5.
- Full Text:
- Date Issued: 2007
Two issues, two groups:
- Authors: du Toit, Jeanne
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159299 , vital:40285 , https://hdl.handle.net/10520/EJC144677
- Description: One of the conference strategies that I found particularly valuable was that of the "syndicate teams" who met regularly to speak on focused topics. Delegates signed up for the topic they were interested in and stayed with that group for the duration of the conference. The list included topics such as the status of journalism education in the academy; the role of journalism in changing the media; adapting journalism education to a digital age, etc.
- Full Text:
- Date Issued: 2007
- Authors: du Toit, Jeanne
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159299 , vital:40285 , https://hdl.handle.net/10520/EJC144677
- Description: One of the conference strategies that I found particularly valuable was that of the "syndicate teams" who met regularly to speak on focused topics. Delegates signed up for the topic they were interested in and stayed with that group for the duration of the conference. The list included topics such as the status of journalism education in the academy; the role of journalism in changing the media; adapting journalism education to a digital age, etc.
- Full Text:
- Date Issued: 2007
Unexpected genetic structure of mussel populations in South Africa: indigenous Perna perna and invasive Mytilus galloprovincialis
- Zardi, Gerardo I, McQuaid, Christopher D, Teske, Peter R, Barker, Nigel P
- Authors: Zardi, Gerardo I , McQuaid, Christopher D , Teske, Peter R , Barker, Nigel P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445564 , vital:74401 , doi:10.3354/meps337135
- Description: Genetic structure of sedentary marine organisms with planktonic larvae can be influenced by oceanographic transport, larval behaviour and local selection. We analysed the population genetic structure (based on mtDNA) of the invasive mussel Mytilus galloprovincialis and the indigenous mussel Perna perna along the southern African coastline. Low genetic divergence of M. galloprovincialis confirms its recent arrival in South Africa. In contrast, the genetic structure of P. perna revealed strong divergence on the south-east coast, forming a western and an eastern lineage. The distribution of the 2 lineages is extraordinary. They overlap for ca. 200 km on the south-east coast, and the western lineage includes animals occurring on either side of a 1000 km break in distribution across the Benguela upwelling system. In cluster analyses, animals on the south coast grouped with others 1000s of km to the west, rather than with those only 200 km to the east.
- Full Text: false
- Date Issued: 2007
- Authors: Zardi, Gerardo I , McQuaid, Christopher D , Teske, Peter R , Barker, Nigel P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445564 , vital:74401 , doi:10.3354/meps337135
- Description: Genetic structure of sedentary marine organisms with planktonic larvae can be influenced by oceanographic transport, larval behaviour and local selection. We analysed the population genetic structure (based on mtDNA) of the invasive mussel Mytilus galloprovincialis and the indigenous mussel Perna perna along the southern African coastline. Low genetic divergence of M. galloprovincialis confirms its recent arrival in South Africa. In contrast, the genetic structure of P. perna revealed strong divergence on the south-east coast, forming a western and an eastern lineage. The distribution of the 2 lineages is extraordinary. They overlap for ca. 200 km on the south-east coast, and the western lineage includes animals occurring on either side of a 1000 km break in distribution across the Benguela upwelling system. In cluster analyses, animals on the south coast grouped with others 1000s of km to the west, rather than with those only 200 km to the east.
- Full Text: false
- Date Issued: 2007
Using the tutorial system to improve the quality of feedback to students in large class teaching
- Snowball, Jeanette D, Sayigh, Elizabeth
- Authors: Snowball, Jeanette D , Sayigh, Elizabeth
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70848 , vital:29752
- Description: In many universities, economics teachers now face the challenge of dealing with large, diverse classes, especially at undergraduate level. A common concern is the non-attendance at lectures of unmotivated (conscript) students. This paper presents the results of a student assessment of a macroeconomics 1 course, coupled with a self-assessment of their own input into the course. The results obtained, using an econometric model, suggest that what students do outside of lectures is equally, or more, important than lecture attendance itself. The paper concludes by examining the possibility of using peer assessed group learning as a feasible way to encourage deep learning in large classes.
- Full Text:
- Date Issued: 2007
- Authors: Snowball, Jeanette D , Sayigh, Elizabeth
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70848 , vital:29752
- Description: In many universities, economics teachers now face the challenge of dealing with large, diverse classes, especially at undergraduate level. A common concern is the non-attendance at lectures of unmotivated (conscript) students. This paper presents the results of a student assessment of a macroeconomics 1 course, coupled with a self-assessment of their own input into the course. The results obtained, using an econometric model, suggest that what students do outside of lectures is equally, or more, important than lecture attendance itself. The paper concludes by examining the possibility of using peer assessed group learning as a feasible way to encourage deep learning in large classes.
- Full Text:
- Date Issued: 2007