Assessing the effects of invasive alien species on rural livelihoods: Case examples and a framework from South Africa
- Shackleton, Charlie M, McGarry, Dylan K, Fourie, Saskia, Gambiza, James, Shackleton, Sheona E, Fabricius, Christo
- Authors: Shackleton, Charlie M , McGarry, Dylan K , Fourie, Saskia , Gambiza, James , Shackleton, Sheona E , Fabricius, Christo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181279 , vital:43715 , xlink:href="https://doi.org/10.1007/s10745-006-9095-0"
- Description: The detrimental impacts of invasive alien species (IAS) on ecosystem goods and services and local and regional economies are well documented. However, the use of IAS by rural communities is little understood, and rarely factored into IAS control programmes. Understanding the use of IAS by rural communities and factoring these into cost-benefit models is complex, depending upon a range of local-level attributes such as the time since invasion, abundance, and local-level costs and benefits. This paper reports on two case studies examining the role of IAS in rural livelihoods in the Eastern Cape, South Africa. In both cases, rural communities made widespread consumptive use of the IAS and generally would prefer higher densities, except in certain key localities. Several households traded in IAS products to generate supplementary income. We present a conceptual framework to guide interpretation of these and future case studies, considering attributes such as time since invasion, the competitiveness of the species, and the relative costs and benefits.
- Full Text:
- Authors: Shackleton, Charlie M , McGarry, Dylan K , Fourie, Saskia , Gambiza, James , Shackleton, Sheona E , Fabricius, Christo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181279 , vital:43715 , xlink:href="https://doi.org/10.1007/s10745-006-9095-0"
- Description: The detrimental impacts of invasive alien species (IAS) on ecosystem goods and services and local and regional economies are well documented. However, the use of IAS by rural communities is little understood, and rarely factored into IAS control programmes. Understanding the use of IAS by rural communities and factoring these into cost-benefit models is complex, depending upon a range of local-level attributes such as the time since invasion, abundance, and local-level costs and benefits. This paper reports on two case studies examining the role of IAS in rural livelihoods in the Eastern Cape, South Africa. In both cases, rural communities made widespread consumptive use of the IAS and generally would prefer higher densities, except in certain key localities. Several households traded in IAS products to generate supplementary income. We present a conceptual framework to guide interpretation of these and future case studies, considering attributes such as time since invasion, the competitiveness of the species, and the relative costs and benefits.
- Full Text:
Automated estimation and analyses of meteorological drought characteristics from monthly rainfall data
- Smakhtin, V U, Hughes, Denis A
- Authors: Smakhtin, V U , Hughes, Denis A
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:7078 , http://hdl.handle.net/10962/d1009746
- Description: The paper describes a new software package for automated estimation, display and analyses of various drought indices – continuous functions of precipitation that allow quantitative assessment of meteorological drought events to be made. The software at present allows up to five different drought indices to be estimated. They include the Decile Index (DI), the Effective Drought Index (EDI), the Standardized Precipitation Index (SPI) and deviations from the long-term mean and median value. Each index can be estimated from point and spatially averaged rainfall data and a number of options are provided for months' selection and the type of the analysis, including a running mean, single value or multiple annual values. The software also allows spell/run analysis to be performed and maps of a specific index to be constructed. The software forms part of the comprehensive computer package, developed earlier and designed to perform the multitude of water resources analyses and hydro-meteorological data processing. The 7-step procedure of setting up and running a typical drought assessment application is described in detail. The examples of applications are given primarily in the specific context of South Asia where the software has been used.
- Full Text:
- Authors: Smakhtin, V U , Hughes, Denis A
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:7078 , http://hdl.handle.net/10962/d1009746
- Description: The paper describes a new software package for automated estimation, display and analyses of various drought indices – continuous functions of precipitation that allow quantitative assessment of meteorological drought events to be made. The software at present allows up to five different drought indices to be estimated. They include the Decile Index (DI), the Effective Drought Index (EDI), the Standardized Precipitation Index (SPI) and deviations from the long-term mean and median value. Each index can be estimated from point and spatially averaged rainfall data and a number of options are provided for months' selection and the type of the analysis, including a running mean, single value or multiple annual values. The software also allows spell/run analysis to be performed and maps of a specific index to be constructed. The software forms part of the comprehensive computer package, developed earlier and designed to perform the multitude of water resources analyses and hydro-meteorological data processing. The 7-step procedure of setting up and running a typical drought assessment application is described in detail. The examples of applications are given primarily in the specific context of South Asia where the software has been used.
- Full Text:
Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera
- Tan, K, Radloff, Sarah E, Li, J J, Hepburn, H Randall, Yang, Ming-Xian, Zhang, L J, Neumann, Peter
- Authors: Tan, K , Radloff, Sarah E , Li, J J , Hepburn, H Randall , Yang, Ming-Xian , Zhang, L J , Neumann, Peter
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6941 , http://hdl.handle.net/10962/d1011965
- Description: The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.
- Full Text:
- Authors: Tan, K , Radloff, Sarah E , Li, J J , Hepburn, H Randall , Yang, Ming-Xian , Zhang, L J , Neumann, Peter
- Date: 2007
- Language: English
- Type: text , Article
- Identifier: vital:6941 , http://hdl.handle.net/10962/d1011965
- Description: The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.
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Bi-Alexandroff spaces
- Authors: Matutu, Phethiwe P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6782 , http://hdl.handle.net/10962/d1006925
- Description: Bi-Alexandroff spaces are defined as extensions of Alexandroff spaces [1]. Urysohn’s lemma for bi-Alexandroff spaces is used to show that upper and lower cozero sets of bitopological spaces are bi-Alexandroff spaces. An adjunction between bi-Alexandroff spaces and pairwise completely regular bitopological spaces is established.
- Full Text:
- Authors: Matutu, Phethiwe P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6782 , http://hdl.handle.net/10962/d1006925
- Description: Bi-Alexandroff spaces are defined as extensions of Alexandroff spaces [1]. Urysohn’s lemma for bi-Alexandroff spaces is used to show that upper and lower cozero sets of bitopological spaces are bi-Alexandroff spaces. An adjunction between bi-Alexandroff spaces and pairwise completely regular bitopological spaces is established.
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Bioremediation of trace organic compounds found in precious metals refineries wastewaters: A review of potential options
- Barbosa, V L, Tandlich, Roman, Burgess, Jo E
- Authors: Barbosa, V L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6469 , http://hdl.handle.net/10962/d1005798 , http://dx.doi.org/10.1016/j.chemosphere.2007.01.018 , http://www.sciencedirect.com/science/article/pii/S0045653507001026
- Description: Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, β-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.
- Full Text:
- Authors: Barbosa, V L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6469 , http://hdl.handle.net/10962/d1005798 , http://dx.doi.org/10.1016/j.chemosphere.2007.01.018 , http://www.sciencedirect.com/science/article/pii/S0045653507001026
- Description: Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, β-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.
- Full Text:
Bones of contention : contestations over human remains in the Eastern Cape
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
- Full Text:
- Authors: Mkhize, Nomalanga
- Date: 2007
- Subjects: Dead -- Political aspects -- South Africa Human body -- Symbolic aspects Human remains (Archaeology) -- Repatriation Human remains (Archaeology) -- Repatriation -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs Eastern Cape (South Africa) -- Social life and customs Eastern Cape (South Africa) -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2597 , http://hdl.handle.net/10962/d1007665
- Description: This thesis examines three contestations involving human remains which have arisen in the Eastern Cape over the past fifteen years. It shows that the value or meaning attached to human remains is constructed through the socio-historical dynamics out of which these contestations arise. The meaning and value of human remains is neither inherent nor neutral. In Ndancama's case, the need for housing in Fingo Village led hundreds of poor residents to settle on the township's Old Cemetery in 1972. Basic material needs trumped concerns for those buried in the cemetery. When the post-apartheid municipality sought to provide sewerage and housing infrastructure for Ndancama in 2003, its development plans were constrained by new heritage legislation which protects historic cemeteries. Residents insisted that their infrastructural needs were of primary importance. In 1993, the unearthing of human remains at the Old Military Cemetery in King William's Town created a thirteen year long saga which was only resolved with the reburial of the remains in 2006. The presence of the remains proved problematic for a number of reasons. Local authorities failed to rebury the remains speedily. The burden to store them fell on the Kaffrarian Museum which came under fire because this was considered unethical in the postapartheid era. The identity of the remains became a bone of contention in 2006 when the new Amathole District Municipality concluded that the remains were those of victims who died in the 1856-57 Great Cattle Killing. The remains and their reburial became symbols of past injustice and present restoration of African heritage. The 1996 quest by 'Nicholas Gcaleka', a 'self-styled' chief and traditional healer, to search for King Hintsa's skull in the United Kingdom provoked unprecedented public engagement with the incomplete narrative on the fate of Hintsa's body. The power to represent history, and the methods through which historical truth is discovered were at the heart of the contestation. Elites such as the Xhosa Royal and the white scientific establishment were considered neither credible nor authoritative on this historical matter. Public support for Gcaleka revealed that many South Africans sought just recompense for colonial injustices.
- Full Text:
Breaking the silence : Zanele's journey to recovery
- Authors: Payne, Charmaine
- Date: 2007
- Subjects: Rape victims -- Counseling of -- South Africa Rape victims -- Counseling of -- South Africa -- Case studies Post-traumatic stress disorder -- Patients -- Rehabilitation Post-traumatic stress disorder -- Patients -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3161 , http://hdl.handle.net/10962/d1007651
- Description: This study employed a case-based research design to document the psychological assessment and treatment of Zanele, a 15-year-old black Xhosa speaking female who was raped twice in 2006 by the same perpetrator. The aim of the study was to explore whether, the model for assessment and intervention for posttraumatic stress disorder (PTSD) developed by Ehlers and Clark (2000) was effective and transportable to the South African context. Zanele had a sufficient understanding of English for assessment to proceed without use of an interpreter. She reported a number of PTSD symptoms which were causing her significant distress and had impacted on her social and educational functioning. These included flashbacks of the perpetrator's face when she looked at the faces of black men, nightmares about the traumas she had endured and feeling isolated from others. A number of cognitive techniques were utilised in this study, however the central interventions included working with triggers, imagery rehearsal techniques with a focus on nightmares, and reliving with cognitive restructuring within and outside reliving. Psychoeducation and increasing her social support were also important components of the intervention. Her progress was monitored by means of several self-report measures which were displayed in graphic and tabular form. In addition, a thematically selective narrative of the assessment and first 23 sessions of the intervention was written which documents some of the central processes set in motion by the interventions. These results provide evidence that this model was both effective and transportable to the South African population. In addition, the study demonstrated that it is possible for a white English speaking clinician to work with a black Xhosa speaking individual and make substantial therapeutic gains.
- Full Text:
- Authors: Payne, Charmaine
- Date: 2007
- Subjects: Rape victims -- Counseling of -- South Africa Rape victims -- Counseling of -- South Africa -- Case studies Post-traumatic stress disorder -- Patients -- Rehabilitation Post-traumatic stress disorder -- Patients -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3161 , http://hdl.handle.net/10962/d1007651
- Description: This study employed a case-based research design to document the psychological assessment and treatment of Zanele, a 15-year-old black Xhosa speaking female who was raped twice in 2006 by the same perpetrator. The aim of the study was to explore whether, the model for assessment and intervention for posttraumatic stress disorder (PTSD) developed by Ehlers and Clark (2000) was effective and transportable to the South African context. Zanele had a sufficient understanding of English for assessment to proceed without use of an interpreter. She reported a number of PTSD symptoms which were causing her significant distress and had impacted on her social and educational functioning. These included flashbacks of the perpetrator's face when she looked at the faces of black men, nightmares about the traumas she had endured and feeling isolated from others. A number of cognitive techniques were utilised in this study, however the central interventions included working with triggers, imagery rehearsal techniques with a focus on nightmares, and reliving with cognitive restructuring within and outside reliving. Psychoeducation and increasing her social support were also important components of the intervention. Her progress was monitored by means of several self-report measures which were displayed in graphic and tabular form. In addition, a thematically selective narrative of the assessment and first 23 sessions of the intervention was written which documents some of the central processes set in motion by the interventions. These results provide evidence that this model was both effective and transportable to the South African population. In addition, the study demonstrated that it is possible for a white English speaking clinician to work with a black Xhosa speaking individual and make substantial therapeutic gains.
- Full Text:
Bridging the gap for Next Generation Services: Presence Services on Legacy Devices
- Moyo, Thamsanqa, Thinyane, Mamello, Wright, Madeleine, Irwin, Barry V W, Clayton, Peter G, Terzoli, Alfredo
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428177 , vital:72491 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428177 , vital:72491 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
Bridging the gap for Next Generation Services: Presence Services on Legacy Devices
- Moyo, Thamsanqa, Thinyane, Mamello, Wright, Madeleine, Irwin, Barry V W, Clayton, Peter G, Terzoli, Alfredo
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428176 , vital:72492 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
- Authors: Moyo, Thamsanqa , Thinyane, Mamello , Wright, Madeleine , Irwin, Barry V W , Clayton, Peter G , Terzoli, Alfredo
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428176 , vital:72492 , https://d1wqtxts1xzle7.cloudfront.net/49665432/Paper_2063_20-_20Moyo-libre.pdf?1476717366=andresponse-content-disposi-tion=inline%3B+filename%3DBridging_the_gap_for_Next_Generation_Ser.pdfandEx-pires=1714737455andSignature=RRbr9pzIYSYX8v7FG6FzV4tu3dFXm9qmmqq5WirOhuYdt--mjOfcDHQNLPYZHCmtgYZWdVk6bVFxfGOVJxgXrvkTe2QN2AZV3XfFTZ3mi1s3A5gw2jIXOVHrYUnaf~POgdijdY85mqWhco3vL6Qk3sOZgYjIlTF5ZGAKg1S54W978Nom01cT2~oqRA0Et6mTNmydWfF5MhFxQIq~LNmYqEqmEESKkkWQFwg6xJJUu0uGffbaZXXBA6oDI2cpfkz1FleKyKaRDRJvdfnuTHPoJJ4TzfO6DDVCWKvJ45jaxIzaGmK-03Ai29I-DPyy-c557kZh~kF3rmDg3zrXVNaL8A__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: Next generation services are provided by applications that leverage packet-based domains. A challenge faced by such services is the support for multiple devices, including legacy devices. Our paper examines a strategy for the pro-vision of next generation services on legacy cellular network devices. We ad-vocate that the provision of next generation services via applications on the SIM card allows for the deployment of such services on legacy devices. We demonstrate this assertion through a proof of concept application, SIMPre, that resides on a SIM card. SIMPre implements a presence service by leveraging Java Card, the SIM Application Toolkit and the OMA IMPS standard. We show that it is possible to provide a next generation service on the SIM card such that it ubiquitously integrates with the functionality of a legacy device. We con-clude through this demonstration that the SIM card is a viable option for provid-ing backward compatibility to legacy devices in the implementation of next generation services.
- Full Text:
Bycatch and discarding in the South African demersal trawl fishery
- Walmsley, Sarah A, Leslie, Rob W, Sauer, Warwick H H
- Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
- Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
- Full Text:
- Authors: Walmsley, Sarah A , Leslie, Rob W , Sauer, Warwick H H
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123944 , vital:35518 , https://doi.10.1016/j.fishres.2007.03.002
- Description: Observers aboard commercial trawlers collected data on the total catch composition of 614 and 479 hauls made by vessels operating off the south and west coasts of South Africa, respectively. On the south coast, four fishing areas were identified on the basis of target species and fishing depth. On the west coast, hauls were separated into those targeting hake Merluccius spp. in four depth ranges (0–300, 301–400, 401–500, and >500 m) and those targeting monkfish Lophius vomerinus. For each area, the catch composition was calculated and the species assemblages were investigated using cluster analysis and multi-dimensional scaling. Finally, for each coast, the weight of fish discarded annually was estimated. On the south coast, although hake dominated, between 21% and 47% of the catch was not hake, depending on the fishing area. In comparison, hake dominated west coast catches, the proportion of hake increasing with depth. For each fishery investigated, approximately 90% of the catch was processed and landed. However, estimates of annual discards indicate that the south and west coast fisheries may annually discard 9000 or 10,000 t and 17,000 or 25,000 t, of undersized and unutilizable fish and offal, respectively, depending on the estimation method used. When developing strategies to limit or enhance utilization of bycatch, cognisance should be taken of the differences in catch composition between the south and west coasts and of the importance of bycatch revenue to south coast fishing companies.
- Full Text:
Camphor-derived chiral auxiliaries: a synthetic, mechanistic and computational study
- Authors: Duggan, Andrew Robert
- Date: 2007
- Subjects: Camphor Chirality Asymmetric synthesis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4415 , http://hdl.handle.net/10962/d1006772
- Description: A broadly based approach has been undertaken to the development and use of camphor derivatives as chiral auxiliaries in asymmetric synthesis – an approach which has embraced synthetic, mechanistic and computational studies. The unambiguous characterization of mono- and dihydroxy-derivatives, obtained by reduction of chiral camphor ether dimers, has been achieved through detailed one- and two-dimensional NMR spectroscopic analysis. The resulting data has been used to establish both the regio- and stereochemistry of the hydroxyl groups. A camphor-derived cyclic iminolactone has been shown to provide a convenient platform for the synthesis of chiral α-amino acids, stereoselective monoalkylation of the iminolactone affording a range of products in yields of 52 - 65 % with up to 85 % d.e. The attempted development of chiral bifunctional Morita-Baylis-Hillman substrates has revealed an unexpected equilibration between isomeric bornane 2,3-diol monoacrylates via acid-catalysed intramolecular transesterification. A detailed [superscript 1]H NMR-based kinetic study of the rearrangement in various media and at various temperatures has permitted the determination of the kinetic and thermodynamic parameters. A computational study at the DFT level has been used to explore the potential energy surfaces of the acid-catalysed and uncatalysed transesterification of the monoacrylate esters. The theoretical data supports the involvement of cyclic intermediates and has provided a rational basis for predicting the favoured reaction pathways. Novel camphor-derived phenyl sulfonate esters and N-adamantylsulfonamides have been synthesised for use as chiral auxiliaries in the Morita-Baylis-Hillman reaction. Modeling at the Molecular Mechanics level has provided useful insights into possible conformational constraints and an adamantyl sulfonate auxiliary has been successfully used in the stereoselective synthesis of a range of products, generally in excellent yield and with up to 95 % d.e.
- Full Text:
- Authors: Duggan, Andrew Robert
- Date: 2007
- Subjects: Camphor Chirality Asymmetric synthesis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4415 , http://hdl.handle.net/10962/d1006772
- Description: A broadly based approach has been undertaken to the development and use of camphor derivatives as chiral auxiliaries in asymmetric synthesis – an approach which has embraced synthetic, mechanistic and computational studies. The unambiguous characterization of mono- and dihydroxy-derivatives, obtained by reduction of chiral camphor ether dimers, has been achieved through detailed one- and two-dimensional NMR spectroscopic analysis. The resulting data has been used to establish both the regio- and stereochemistry of the hydroxyl groups. A camphor-derived cyclic iminolactone has been shown to provide a convenient platform for the synthesis of chiral α-amino acids, stereoselective monoalkylation of the iminolactone affording a range of products in yields of 52 - 65 % with up to 85 % d.e. The attempted development of chiral bifunctional Morita-Baylis-Hillman substrates has revealed an unexpected equilibration between isomeric bornane 2,3-diol monoacrylates via acid-catalysed intramolecular transesterification. A detailed [superscript 1]H NMR-based kinetic study of the rearrangement in various media and at various temperatures has permitted the determination of the kinetic and thermodynamic parameters. A computational study at the DFT level has been used to explore the potential energy surfaces of the acid-catalysed and uncatalysed transesterification of the monoacrylate esters. The theoretical data supports the involvement of cyclic intermediates and has provided a rational basis for predicting the favoured reaction pathways. Novel camphor-derived phenyl sulfonate esters and N-adamantylsulfonamides have been synthesised for use as chiral auxiliaries in the Morita-Baylis-Hillman reaction. Modeling at the Molecular Mechanics level has provided useful insights into possible conformational constraints and an adamantyl sulfonate auxiliary has been successfully used in the stereoselective synthesis of a range of products, generally in excellent yield and with up to 95 % d.e.
- Full Text:
Catalytic activities of metallophthalocyanines towards detection and transformation of pollutants
- Authors: Agboola, Bolade Oyeyinka
- Date: 2007
- Subjects: Phthalocyanines Electrochemistry Pollutants -- Biodegradation Pollutants -- Measurement
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4427 , http://hdl.handle.net/10962/d1006922
- Description: Syntheses, spectral, electrochemical and spectroelectrochemical studies of new thiol-derivatised MPc complexes were satisfactorily carried out. For the first time, spectroelectrochemistry gave evidence for the formation of Ni²⁺/Ni⁺ process in a NiPc complex. Significant insights as to the nature of Fe⁺Pc and Ni⁺Pc spectra were obtained. Transformations of chlorophenols using chemical and photochemical methods are presented. For cobalt tetrasulphophthalocyanine catalysed oxidation of chlorophenols using hydrogen peroxide as the oxidant, types of oxidation products formed depended on the solvent conditions. Photolysis of aqueous solutions of chlorophenols in the presence of immobilised non-transition metal phthalocyanine photosensitisers onto Amerlite® was carried out. For the first time, MPcS[subscript mix] complexes were immobilised on Amberlite® for use in heterogeneous photocatalysis. Photolysis of the chlorophenols resulted mainly in the formation of chlorobenzoquinone derivatives. The generation of singlet oxygen (¹O₂) by these immobilised MPc photosensitisers was found to play a major role in their photoactivities. Modifications of gold electrodes with the newly synthesised thiol-derivatised MPc complexes via electropolymerisation and SAM techniques are presented. Cyclic voltammetry, impedance spectroscopy (NiPcs only) and spectroelectrochemical techniques (NiPcs only) confirmed that the complexes formed films on gold electrodes. Stable and well packed SAM films as evidenced by the voltammetric characterisation were obtained. For the first time, optimisation of the time for SAM formation based on CV technique was studied. First example of a formation of MnPc-SAM was achieved. Catalytic activities of the NiPc towards chlorophenol depended on the nature of the NiPc in the polymer films and also anti-fouling ability of the films depended on polymer film thickness. The FeTBMPc polymer modified gold electrode showed the best catalytic activity in terms of peak potential, E[subscript p] when compared to reported work in literature for nitrate electrooxidation. Cyclic voltammetry and spectroscopy studies showed that the CoPcs, FePcs and NiPcs catalysed nitrite oxidation involve 2 electrons in total while that of McPcs involve 1 electron. Better catalytic performance towards sulphite electrooxidation were obtained for the CoPcs, FePcs and MnPcs which have metal based redox processes within the range of the sulphite electrooxidation peak while the NiPcs which did not show metal based oxidation reaction performed less.
- Full Text:
- Authors: Agboola, Bolade Oyeyinka
- Date: 2007
- Subjects: Phthalocyanines Electrochemistry Pollutants -- Biodegradation Pollutants -- Measurement
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4427 , http://hdl.handle.net/10962/d1006922
- Description: Syntheses, spectral, electrochemical and spectroelectrochemical studies of new thiol-derivatised MPc complexes were satisfactorily carried out. For the first time, spectroelectrochemistry gave evidence for the formation of Ni²⁺/Ni⁺ process in a NiPc complex. Significant insights as to the nature of Fe⁺Pc and Ni⁺Pc spectra were obtained. Transformations of chlorophenols using chemical and photochemical methods are presented. For cobalt tetrasulphophthalocyanine catalysed oxidation of chlorophenols using hydrogen peroxide as the oxidant, types of oxidation products formed depended on the solvent conditions. Photolysis of aqueous solutions of chlorophenols in the presence of immobilised non-transition metal phthalocyanine photosensitisers onto Amerlite® was carried out. For the first time, MPcS[subscript mix] complexes were immobilised on Amberlite® for use in heterogeneous photocatalysis. Photolysis of the chlorophenols resulted mainly in the formation of chlorobenzoquinone derivatives. The generation of singlet oxygen (¹O₂) by these immobilised MPc photosensitisers was found to play a major role in their photoactivities. Modifications of gold electrodes with the newly synthesised thiol-derivatised MPc complexes via electropolymerisation and SAM techniques are presented. Cyclic voltammetry, impedance spectroscopy (NiPcs only) and spectroelectrochemical techniques (NiPcs only) confirmed that the complexes formed films on gold electrodes. Stable and well packed SAM films as evidenced by the voltammetric characterisation were obtained. For the first time, optimisation of the time for SAM formation based on CV technique was studied. First example of a formation of MnPc-SAM was achieved. Catalytic activities of the NiPc towards chlorophenol depended on the nature of the NiPc in the polymer films and also anti-fouling ability of the films depended on polymer film thickness. The FeTBMPc polymer modified gold electrode showed the best catalytic activity in terms of peak potential, E[subscript p] when compared to reported work in literature for nitrate electrooxidation. Cyclic voltammetry and spectroscopy studies showed that the CoPcs, FePcs and NiPcs catalysed nitrite oxidation involve 2 electrons in total while that of McPcs involve 1 electron. Better catalytic performance towards sulphite electrooxidation were obtained for the CoPcs, FePcs and MnPcs which have metal based redox processes within the range of the sulphite electrooxidation peak while the NiPcs which did not show metal based oxidation reaction performed less.
- Full Text:
Causes of persistent rural poverty in Thika district of Kenya, c.1953-2000
- Authors: Kinyanjui, Felistus Kinuna
- Date: 2007
- Subjects: Poverty -- Kenya -- History Rural poor -- Kenya -- History Agriculture -- Kenya -- History Kenya -- History Kenya -- Politics and government
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2547 , http://hdl.handle.net/10962/d1002399
- Description: This study investigates the causes of poverty among the residents of Thika District in Kenya over the period 1953-2000. Using the articulation of modes of production perspective, the study traces the dynamics of poverty to the geography, history and politics of Thika District. The thrust of the argument is that livelihoods in the district changed during the period under investigation, but not necessarily for the better. Landlessness, collapse of the coffee industry, intergenerational poverty, and the ravages of diseases (particularly of HIV/AIDS) are analysed. This leads to the conclusion that causes of poverty in Thika District during the period under examination were complex as one form of deprivation led to another. The study established that poverty in Thika District during the period under review was a product of a process of exclusion from the centre of political power and appropriation. While race was the basis for allocation of public resources in colonial Kenya, ethnicity has dominated the independence period. Consequently, one would have expected the residents of Thika District, the home of Kenya’s first president, Mzee Jomo Kenyatta, to have benefited inordinately from public resources during his rule. Kenyatta’s administration, however, mainly benefited the Kikuyu elite. The study therefore demonstrates that during the period under examination, the Kikuyu, like any other Kenyan community, were a heterogeneous group whose differences were accentuated by class relations. Subaltern groups in Thika District therefore benefited minimally from state patronage, just like similar groups elsewhere in rural Kenya. By the late 1970s, the level of deprivation in rural Kenya had been contained as a result of favourable prices for the country’s agricultural exports. But in the subsequent period, poverty increased under the pressures of world economic recession and slowdowns in trade. The situation was worse for Kikuyu peasants as the Second Republic of President Daniel Moi deliberately attempted undermine the Kikuyu economically. For the majority of Thika residents, this translated into further marginalisation as the Moi regime lumped them together with the Kikuyu elite who had benefitted inordinately from public resources during the Kenyatta era. This study demonstrates that no single factor can explain the prevalence of poverty in Thika District during the period under consideration. However, the poor in the district devised survival mechanisms that could be replicated elsewhere. Indeed, the dynamics of poverty in Thika District represent a microcosm not just for the broader Kenyan situation but also of rural livelihoods elsewhere in the world. The study recommends land reform and horticulture as possible ways of reducing poverty among rural communities. Further, for a successful global war on poverty there is an urgent need to have the West go beyond rhetoric and deliver on its promises to make poverty history.
- Full Text:
- Authors: Kinyanjui, Felistus Kinuna
- Date: 2007
- Subjects: Poverty -- Kenya -- History Rural poor -- Kenya -- History Agriculture -- Kenya -- History Kenya -- History Kenya -- Politics and government
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2547 , http://hdl.handle.net/10962/d1002399
- Description: This study investigates the causes of poverty among the residents of Thika District in Kenya over the period 1953-2000. Using the articulation of modes of production perspective, the study traces the dynamics of poverty to the geography, history and politics of Thika District. The thrust of the argument is that livelihoods in the district changed during the period under investigation, but not necessarily for the better. Landlessness, collapse of the coffee industry, intergenerational poverty, and the ravages of diseases (particularly of HIV/AIDS) are analysed. This leads to the conclusion that causes of poverty in Thika District during the period under examination were complex as one form of deprivation led to another. The study established that poverty in Thika District during the period under review was a product of a process of exclusion from the centre of political power and appropriation. While race was the basis for allocation of public resources in colonial Kenya, ethnicity has dominated the independence period. Consequently, one would have expected the residents of Thika District, the home of Kenya’s first president, Mzee Jomo Kenyatta, to have benefited inordinately from public resources during his rule. Kenyatta’s administration, however, mainly benefited the Kikuyu elite. The study therefore demonstrates that during the period under examination, the Kikuyu, like any other Kenyan community, were a heterogeneous group whose differences were accentuated by class relations. Subaltern groups in Thika District therefore benefited minimally from state patronage, just like similar groups elsewhere in rural Kenya. By the late 1970s, the level of deprivation in rural Kenya had been contained as a result of favourable prices for the country’s agricultural exports. But in the subsequent period, poverty increased under the pressures of world economic recession and slowdowns in trade. The situation was worse for Kikuyu peasants as the Second Republic of President Daniel Moi deliberately attempted undermine the Kikuyu economically. For the majority of Thika residents, this translated into further marginalisation as the Moi regime lumped them together with the Kikuyu elite who had benefitted inordinately from public resources during the Kenyatta era. This study demonstrates that no single factor can explain the prevalence of poverty in Thika District during the period under consideration. However, the poor in the district devised survival mechanisms that could be replicated elsewhere. Indeed, the dynamics of poverty in Thika District represent a microcosm not just for the broader Kenyan situation but also of rural livelihoods elsewhere in the world. The study recommends land reform and horticulture as possible ways of reducing poverty among rural communities. Further, for a successful global war on poverty there is an urgent need to have the West go beyond rhetoric and deliver on its promises to make poverty history.
- Full Text:
Changes in fuelwood use and selection following electrification in the Bushbuckridge lowveld, South Africa
- Madubansi, Mainza, Shackleton, Charlie M
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6641 , http://hdl.handle.net/10962/d1006867
- Description: Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed.
- Full Text:
- Authors: Madubansi, Mainza , Shackleton, Charlie M
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6641 , http://hdl.handle.net/10962/d1006867
- Description: Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed.
- Full Text:
Characterisation of Human Hsj1a : an HSP40 molecular chaperone similar to Malarial Pfj4
- Authors: McNamara, Caryn
- Date: 2007
- Subjects: Heat shock proteins , Protein folding , Proteins -- Analysis , Proteins -- Structure , Plasmodium , Malaria , Molecular chaperones
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4083 , http://hdl.handle.net/10962/d1007603
- Description: Protein folding, translocation, oligomeric rearrangement and degradation are vital functions to obtain correctly folded proteins in any cell. The constitutive or stress-induced members of each of the heat shock protein (Hsp) families, namely Hsp70 and Hsp40, make up the Hsp70/Hsp40 chaperone system. The Hsp40 J-domain is important for the Hsp70-Hsp40 interaction and hence function. The type-II Hsp40 proteins, Homo sapiens DnaJ 1a (Hsj1a) and Plasmodium falciparum DnaJ 4 (Pfj4), are structurally similar suggesting possible similar roles during malarial infection. This thesis has focussed on identifying whether Hsj1a and Pfj4 are functionally similar in their interaction with potential partner Hsp70 chaperones. Analysis in silico also showed Pfj4 to have a potential chaperone domain, a region resembling a ubiquitin-interacting motif (UIM) corresponding to UIM1 of HsjIa, and another highly conserved region was noted between residues 232-241. The highly conserved regions within the Hsp40 J-domains, and those amino acids therein, are suggested to be responsible for mediating this Hsp70-Hsp40 partner interaction. The thermosensitive dnaJ cbpA Escherichia coli OD259 mutant strain producing type-I Agrobacterium tumefaciens DnaJ (AgtDnaJ) was used as a model heterologous expression system in this study. AgtDnaJ was able to replace the lack of two E coli Hsp40s in vivo, DnaJ and CbpA, whereas AgtDnaJ(H33Q) was unable to. AgtDnaJ-based chimeras containing the swapped J-domains of similar type-II Hsp40 proteins, namely Hsj1Agt and Pfj4Agt, were also able to replace these in E. coli OD259. Conserved J-domain amino acids were identified and were substituted in these chimeras. Of these mutant proteins, Hsj IAgt(L8A), Hsj1Agt(R24A), Hsj1Agt(H31Q), Pfj4Agt(L 11A) and Pfj4Agt(H34Q) were not able to replace the E. coli Hsp40s, whilst Pfj4Agt(Y8A) and Pfj4Agt(R27A) were only able to partially replace them. This shows the leucine of helix I and the histidine of the loop region are key in the in vivo function of both proteins and that the arginine of helix II is key for Hsj1a. The histidine-tagged Hsj1a protein was also successfully purified from the heterologous system. The in vitro stimulated ATPase activity of human Hsp70 by Hsj1a was found to be approximately 14 nmol Pí[subscript]/min/mg, and yet not stimulated by Pfj4, suggesting a possible species-specific interaction is occurring.
- Full Text:
- Authors: McNamara, Caryn
- Date: 2007
- Subjects: Heat shock proteins , Protein folding , Proteins -- Analysis , Proteins -- Structure , Plasmodium , Malaria , Molecular chaperones
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4083 , http://hdl.handle.net/10962/d1007603
- Description: Protein folding, translocation, oligomeric rearrangement and degradation are vital functions to obtain correctly folded proteins in any cell. The constitutive or stress-induced members of each of the heat shock protein (Hsp) families, namely Hsp70 and Hsp40, make up the Hsp70/Hsp40 chaperone system. The Hsp40 J-domain is important for the Hsp70-Hsp40 interaction and hence function. The type-II Hsp40 proteins, Homo sapiens DnaJ 1a (Hsj1a) and Plasmodium falciparum DnaJ 4 (Pfj4), are structurally similar suggesting possible similar roles during malarial infection. This thesis has focussed on identifying whether Hsj1a and Pfj4 are functionally similar in their interaction with potential partner Hsp70 chaperones. Analysis in silico also showed Pfj4 to have a potential chaperone domain, a region resembling a ubiquitin-interacting motif (UIM) corresponding to UIM1 of HsjIa, and another highly conserved region was noted between residues 232-241. The highly conserved regions within the Hsp40 J-domains, and those amino acids therein, are suggested to be responsible for mediating this Hsp70-Hsp40 partner interaction. The thermosensitive dnaJ cbpA Escherichia coli OD259 mutant strain producing type-I Agrobacterium tumefaciens DnaJ (AgtDnaJ) was used as a model heterologous expression system in this study. AgtDnaJ was able to replace the lack of two E coli Hsp40s in vivo, DnaJ and CbpA, whereas AgtDnaJ(H33Q) was unable to. AgtDnaJ-based chimeras containing the swapped J-domains of similar type-II Hsp40 proteins, namely Hsj1Agt and Pfj4Agt, were also able to replace these in E. coli OD259. Conserved J-domain amino acids were identified and were substituted in these chimeras. Of these mutant proteins, Hsj IAgt(L8A), Hsj1Agt(R24A), Hsj1Agt(H31Q), Pfj4Agt(L 11A) and Pfj4Agt(H34Q) were not able to replace the E. coli Hsp40s, whilst Pfj4Agt(Y8A) and Pfj4Agt(R27A) were only able to partially replace them. This shows the leucine of helix I and the histidine of the loop region are key in the in vivo function of both proteins and that the arginine of helix II is key for Hsj1a. The histidine-tagged Hsj1a protein was also successfully purified from the heterologous system. The in vitro stimulated ATPase activity of human Hsp70 by Hsj1a was found to be approximately 14 nmol Pí[subscript]/min/mg, and yet not stimulated by Pfj4, suggesting a possible species-specific interaction is occurring.
- Full Text:
Characterization of self-assembled monolayers of iron and cobalt octaalkylthiosubstituted phthalocyanines and their use in nitrite electrocatalytic oxidation
- Matemadombo, Fungisai, Nyokong, Tebello
- Authors: Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271182 , vital:54519 , xlink:href="https://doi.org/10.1016/j.electacta.2007.05.002"
- Description: Cobalt and iron phenylthiosubstituted phthalocyanines have been deposited on Au electrode surfaces through the self-assembled monolayer (SAM) technique. The so formed layers were studied using voltammetric and impedance techniques. These SAMs blocked a number of Faradic processes and electrocatalyzed the oxidation of nitrite. The electrocatalytic parameters of the cobalt and iron phenylthiosubstituted phthalocyanines deposited on Au electrodes in nitrite solution were studied. Nitrite overpotentials which are lower than ever reported were obtained in this work for the iron phenylthiosubstituted phthalocyanines with very high stability.
- Full Text:
- Authors: Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271182 , vital:54519 , xlink:href="https://doi.org/10.1016/j.electacta.2007.05.002"
- Description: Cobalt and iron phenylthiosubstituted phthalocyanines have been deposited on Au electrode surfaces through the self-assembled monolayer (SAM) technique. The so formed layers were studied using voltammetric and impedance techniques. These SAMs blocked a number of Faradic processes and electrocatalyzed the oxidation of nitrite. The electrocatalytic parameters of the cobalt and iron phenylthiosubstituted phthalocyanines deposited on Au electrodes in nitrite solution were studied. Nitrite overpotentials which are lower than ever reported were obtained in this work for the iron phenylthiosubstituted phthalocyanines with very high stability.
- Full Text:
Climate change, genetics or human choice: why were the shells of mankind’s earliest ornament larger in the Pleistocene than in the Holocene?
- Teske, Peter R, Papadopoulos, Isabelle, McQuaid, Christopher D, Newman, Brent K, Barker, Nigel P
- Authors: Teske, Peter R , Papadopoulos, Isabelle , McQuaid, Christopher D , Newman, Brent K , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6952 , http://hdl.handle.net/10962/d1011984
- Description: The southern African tick shell, Nassarius kraussianus (Dunker, 1846), has been identified as being the earliest known ornamental object used by human beings. Shell beads dated from ~75,000 years ago (Pleistocene era) were found in a cave located on South Africa's south coast. Beads made from N. kraussianus shells have also been found in deposits in this region dating from the beginning of the Holocene era (<10,000 years ago). These younger shells were significantly smaller, a phenomenon that has been attributed to a change in human preference. We investigated two alternative hypotheses explaining the difference in shell size: a) N. kraussianus comprises at least two genetic lineages that differ in size; b) the difference in shell size is due to phenotypic plasticity and is a function of environmental conditions. To test these hypotheses, we first reconstructed the species' phylogeographic history, and second, we measured the shell sizes of extant individuals throughout South Africa. Although two genetic lineages were identified, the sharing of haplotypes between these suggests that there is no genetic basis for the size differences. Extant individuals from the cool temperate west coast had significantly larger shells than populations in the remainder of the country, suggesting that N. kraussianus grows to a larger size in colder water. The decrease in fossil shell size from Pleistocene to Holocene was likely due to increased temperatures as a result of climate change at the beginning of the present interglacial period. We hypothesise that the sizes of N. kraussianus fossil shells can therefore serve as indicators of the climatic conditions that were prevalent in a particular region at the time when they were deposited. Moreover, N. kraussianus could serve as a biomonitor to study the impacts of future climate change on coastal biota in southern Africa.
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- Authors: Teske, Peter R , Papadopoulos, Isabelle , McQuaid, Christopher D , Newman, Brent K , Barker, Nigel P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6952 , http://hdl.handle.net/10962/d1011984
- Description: The southern African tick shell, Nassarius kraussianus (Dunker, 1846), has been identified as being the earliest known ornamental object used by human beings. Shell beads dated from ~75,000 years ago (Pleistocene era) were found in a cave located on South Africa's south coast. Beads made from N. kraussianus shells have also been found in deposits in this region dating from the beginning of the Holocene era (<10,000 years ago). These younger shells were significantly smaller, a phenomenon that has been attributed to a change in human preference. We investigated two alternative hypotheses explaining the difference in shell size: a) N. kraussianus comprises at least two genetic lineages that differ in size; b) the difference in shell size is due to phenotypic plasticity and is a function of environmental conditions. To test these hypotheses, we first reconstructed the species' phylogeographic history, and second, we measured the shell sizes of extant individuals throughout South Africa. Although two genetic lineages were identified, the sharing of haplotypes between these suggests that there is no genetic basis for the size differences. Extant individuals from the cool temperate west coast had significantly larger shells than populations in the remainder of the country, suggesting that N. kraussianus grows to a larger size in colder water. The decrease in fossil shell size from Pleistocene to Holocene was likely due to increased temperatures as a result of climate change at the beginning of the present interglacial period. We hypothesise that the sizes of N. kraussianus fossil shells can therefore serve as indicators of the climatic conditions that were prevalent in a particular region at the time when they were deposited. Moreover, N. kraussianus could serve as a biomonitor to study the impacts of future climate change on coastal biota in southern Africa.
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Co-engaged learning : Xhosa women's narratives on traditional foods
- Authors: Jolly, Rachel
- Date: 2007
- Subjects: Xhosa (African people) -- Social life and customs -- South Africa -- Grahamstown Women, Xhosa -- South Africa -- Grahamstown Nutrition -- Study and teaching -- South Africa -- Grahamstown Ethnoscience -- Study and teaching -- South Africa -- Grahamstown AIDS (Disease) -- South Africa -- Grahamstown HIV infections -- South Africa -- Grahamstown Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1450 , http://hdl.handle.net/10962/d1003331
- Description: This interpretive case study examines Grahamstown East Xhosa women's narratives on the nutritional value of traditional foods. It reviews reflexive learning interactions apparent in the co-engaged narratives of food preparation practices. The research design incorporates methods of reflective co-engagement through which a small team of women were approached as 'co-researchers' in order to work together on shared, local knowledge capital and nutrition concerns. It draws on findings generated using a combination of semi-structured interviews, cooking demonstrations, videography, photographs and field observations as methods of data collection. Data were member-checked and reviewed in a rural context before the emerging evidence was analyzed using Bassey's (1999) analytical statements. Contextual factors influencing the study are high poverty, unemployment and HIV/AIDS prevalence where nutrition levels have been found to be low. The women making up the study have spent the majority of their lives in the peri-urban area of Grahamstown and in some cases, are more than one generation removed from rural living and its associated knowledge. The accompanying shift to modernization was found to influence the interplay between their narratives and practice. Indigenous Knowledge is often characterized by being situated in practice with the knowledge-holders often not 'knowing that they know.' This study concludes that it is not possible to assume that knowledge can always be consciously expressed, especially when that knowledge is embedded in practice. Related to this, co-engagement and diversity among the group gave rise to greater disequilibrium as well as making the knowledge more explicit and hence, available for reflection. The study suggests that through the process of co-engagement and deliberation around indigenous ways of knowing, agency and cultural identity appears to be enabled and strengthened.
- Full Text:
- Authors: Jolly, Rachel
- Date: 2007
- Subjects: Xhosa (African people) -- Social life and customs -- South Africa -- Grahamstown Women, Xhosa -- South Africa -- Grahamstown Nutrition -- Study and teaching -- South Africa -- Grahamstown Ethnoscience -- Study and teaching -- South Africa -- Grahamstown AIDS (Disease) -- South Africa -- Grahamstown HIV infections -- South Africa -- Grahamstown Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1450 , http://hdl.handle.net/10962/d1003331
- Description: This interpretive case study examines Grahamstown East Xhosa women's narratives on the nutritional value of traditional foods. It reviews reflexive learning interactions apparent in the co-engaged narratives of food preparation practices. The research design incorporates methods of reflective co-engagement through which a small team of women were approached as 'co-researchers' in order to work together on shared, local knowledge capital and nutrition concerns. It draws on findings generated using a combination of semi-structured interviews, cooking demonstrations, videography, photographs and field observations as methods of data collection. Data were member-checked and reviewed in a rural context before the emerging evidence was analyzed using Bassey's (1999) analytical statements. Contextual factors influencing the study are high poverty, unemployment and HIV/AIDS prevalence where nutrition levels have been found to be low. The women making up the study have spent the majority of their lives in the peri-urban area of Grahamstown and in some cases, are more than one generation removed from rural living and its associated knowledge. The accompanying shift to modernization was found to influence the interplay between their narratives and practice. Indigenous Knowledge is often characterized by being situated in practice with the knowledge-holders often not 'knowing that they know.' This study concludes that it is not possible to assume that knowledge can always be consciously expressed, especially when that knowledge is embedded in practice. Related to this, co-engagement and diversity among the group gave rise to greater disequilibrium as well as making the knowledge more explicit and hence, available for reflection. The study suggests that through the process of co-engagement and deliberation around indigenous ways of knowing, agency and cultural identity appears to be enabled and strengthened.
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Cobalt Phthalocyanine Molecular Electrode for the Electrochemical Investigation of the Release of Glutathione upon Copper-Catalyzed Decomposition of S-Nitrosoglutathione
- Sehlotho, Nthapo, Griveau, Sophie, Nyokong, Tebello, Bedioui, Fethi
- Authors: Sehlotho, Nthapo , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281201 , vital:55701 , xlink:href="https://doi.org/10.1002/elan.200603656"
- Description: Decomposition of S-nitrosoglutathione (GSNO) in phosphate buffer solution at physiological pH 7.4 in the presence of cuprous ion as a catalyst and sodium borohydride as a reducing agent is analyzed by observing the transient apparition of reduced glutathione GSH through its electrooxidation. Transient formation of GSH, upon decomposition of 1 mM GSNO in presence of 0.025 mM Cu(NO3)2 and 1 mM NaBH4 was detected by using an ordinary pyrolytic graphite electrode modified with an adsorbed monolayer of cobalt phthalocyanine at 0 V vs. SCE.
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- Authors: Sehlotho, Nthapo , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281201 , vital:55701 , xlink:href="https://doi.org/10.1002/elan.200603656"
- Description: Decomposition of S-nitrosoglutathione (GSNO) in phosphate buffer solution at physiological pH 7.4 in the presence of cuprous ion as a catalyst and sodium borohydride as a reducing agent is analyzed by observing the transient apparition of reduced glutathione GSH through its electrooxidation. Transient formation of GSH, upon decomposition of 1 mM GSNO in presence of 0.025 mM Cu(NO3)2 and 1 mM NaBH4 was detected by using an ordinary pyrolytic graphite electrode modified with an adsorbed monolayer of cobalt phthalocyanine at 0 V vs. SCE.
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Collaborative versus adversarial stances in scientific discourse : implications for the role of systematic case studies in the development of evidence-based practice in psychotherapy
- Authors: Edwards, David J A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6245 , http://hdl.handle.net/10962/d1007861
- Description: There is still a need for advocacy in the promotion of case study research because there has been insufficient appreciation of its role as a source of evidence relevant to the development and evaluation of practice in psychotherapy. Distorted use of terms like "gold standard", "anecdotal",and "empirical" in the discourse in which research methodology is typically presented has disempowered the practitioner's perspective and discredited the role of case-based knowledge building. The framework of evidence-based practice (EBP) recognizes the complementarity of different research methods and acknowledges the significance of casebased research. To spell out some of these complementary links, a typology of seven research methods - including both experimental group comparison designs and individual case studies - is proposed and the contribution of each to the development of EBP is set out. Finally some suggestions are made for strategies to promote the publication of high quality case studies.
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- Authors: Edwards, David J A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6245 , http://hdl.handle.net/10962/d1007861
- Description: There is still a need for advocacy in the promotion of case study research because there has been insufficient appreciation of its role as a source of evidence relevant to the development and evaluation of practice in psychotherapy. Distorted use of terms like "gold standard", "anecdotal",and "empirical" in the discourse in which research methodology is typically presented has disempowered the practitioner's perspective and discredited the role of case-based knowledge building. The framework of evidence-based practice (EBP) recognizes the complementarity of different research methods and acknowledges the significance of casebased research. To spell out some of these complementary links, a typology of seven research methods - including both experimental group comparison designs and individual case studies - is proposed and the contribution of each to the development of EBP is set out. Finally some suggestions are made for strategies to promote the publication of high quality case studies.
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