The invisible enemy of satellite electronics
- Authors: Smith, Farouk
- Subjects: Aerospace engineering , Extraterrestrial radiation , f-sa
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/10948/53574 , vital:45642
- Description: Spacecraft electronics are susceptible to the adverse effects of space radiation. Our jobs as engineers and scientists is to find ways to characterize these effects and find ways to mitigate it in order to ensure seamless operation of the satellite mission.
- Full Text:
- Authors: Smith, Farouk
- Subjects: Aerospace engineering , Extraterrestrial radiation , f-sa
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/10948/53574 , vital:45642
- Description: Spacecraft electronics are susceptible to the adverse effects of space radiation. Our jobs as engineers and scientists is to find ways to characterize these effects and find ways to mitigate it in order to ensure seamless operation of the satellite mission.
- Full Text:
Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Simon, Carol A, Booth, Anthony J
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
- Full Text:
- Date Issued: 2010
Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
- Full Text:
- Date Issued: 2010
Framework for local government to implement integrated water resource management linked to water service delivery
- Haigh, Eliria H, Fox, Helen E, Davies-Coleman, H D
- Authors: Haigh, Eliria H , Fox, Helen E , Davies-Coleman, H D
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:7097 , http://hdl.handle.net/10962/d1012440
- Description: The Water Services Act (No. 8 of 1997) of South Africa states that water service delivery is the responsibility of local government as Water Services Authorities. The principal legal responsibility is to complete a Water Services Development Plan (WSDP) every 5 years with annual review. The WSDP encapsulates all the responsibilities and tasks required in water service delivery. However, it does not spell out local government’s role in water resource protection or its responsibilities as far as integrated water resource management is concerned. It is well known in South Africa that there is a challenging level of inadequate capacity in technical and administrative skills in local government to adequately fulfil water service delivery. This paper highlights the consequences of this incapacity for municipalities and their difficulties in fulfilling their responsibilities as service providers. A framework is provided within which improvements can be brought about, with guidance on how to engage in the practice of integrated water resource management (IWRM) in the context of the legal framework for water services. The additional tasks and changes required to practise IWRM are set in the context of the WSDP. The framework provides a guide for a municipality to first accomplish an adequate WSDP, and then to gradually implement IWRM. A discussion on the skills needed to accomplish, firstly, a comprehensive WSDP, and secondly, IWRM, is included.
- Full Text:
- Date Issued: 2010
- Authors: Haigh, Eliria H , Fox, Helen E , Davies-Coleman, H D
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:7097 , http://hdl.handle.net/10962/d1012440
- Description: The Water Services Act (No. 8 of 1997) of South Africa states that water service delivery is the responsibility of local government as Water Services Authorities. The principal legal responsibility is to complete a Water Services Development Plan (WSDP) every 5 years with annual review. The WSDP encapsulates all the responsibilities and tasks required in water service delivery. However, it does not spell out local government’s role in water resource protection or its responsibilities as far as integrated water resource management is concerned. It is well known in South Africa that there is a challenging level of inadequate capacity in technical and administrative skills in local government to adequately fulfil water service delivery. This paper highlights the consequences of this incapacity for municipalities and their difficulties in fulfilling their responsibilities as service providers. A framework is provided within which improvements can be brought about, with guidance on how to engage in the practice of integrated water resource management (IWRM) in the context of the legal framework for water services. The additional tasks and changes required to practise IWRM are set in the context of the WSDP. The framework provides a guide for a municipality to first accomplish an adequate WSDP, and then to gradually implement IWRM. A discussion on the skills needed to accomplish, firstly, a comprehensive WSDP, and secondly, IWRM, is included.
- Full Text:
- Date Issued: 2010
Omics-based molecular techniques in oral pathology centred cancer: prospect and challenges in Africa
- Adeola, Henry A., Soyele, Olujide.O., Adefuye, Anthonio O., Jimoh, Sikiru A., Butali, Azeez
- Authors: Adeola, Henry A. , Soyele, Olujide.O. , Adefuye, Anthonio O. , Jimoh, Sikiru A. , Butali, Azeez
- Date: 2017
- Subjects: Eastern Cape, South Africa Oral mucosa--Cancer Oral Pathology Cancer Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5857 , vital:44658 , https://DOI10.1186/s12935-017-0432-8
- Description: Background:The completion of the human genome project and the accomplished milestones in the human proteome project; as well as the progress made so far in computational bioinformatics and “big data” processing have contributed immensely to individualized/personalized medicine in the developed world.Main body:At the dawn of precision medicine, various omics-based therapies and bioengineering can now be applied accurately for the diagnosis, prognosis, treatment, and risk stratification of cancer in a manner that was hitherto not thought possible. The widespread introduction of genomics and other omics-based approaches into the postgraduate training curriculum of diverse medical and dental specialties, including pathology has improved the proficiency of practitioners in the use of novel molecular signatures in patient management. In addition, intricate details about disease disparity among different human populations are beginning to emerge. This would facilitate the use of tailor-made novel theranostic methods based on emerging molecular evidences.Conclusion:In this review, we examined the challenges and prospects of using currently available omics-based technologies vis-à-vis oral pathology as well as prompt cancer diagnosis and treatment in a resource limited setting.Keywords:Omics-based, Molecular, Developing world, Oral pathology, Challenges
- Full Text:
- Date Issued: 2017
Omics-based molecular techniques in oral pathology centred cancer: prospect and challenges in Africa
- Authors: Adeola, Henry A. , Soyele, Olujide.O. , Adefuye, Anthonio O. , Jimoh, Sikiru A. , Butali, Azeez
- Date: 2017
- Subjects: Eastern Cape, South Africa Oral mucosa--Cancer Oral Pathology Cancer Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5857 , vital:44658 , https://DOI10.1186/s12935-017-0432-8
- Description: Background:The completion of the human genome project and the accomplished milestones in the human proteome project; as well as the progress made so far in computational bioinformatics and “big data” processing have contributed immensely to individualized/personalized medicine in the developed world.Main body:At the dawn of precision medicine, various omics-based therapies and bioengineering can now be applied accurately for the diagnosis, prognosis, treatment, and risk stratification of cancer in a manner that was hitherto not thought possible. The widespread introduction of genomics and other omics-based approaches into the postgraduate training curriculum of diverse medical and dental specialties, including pathology has improved the proficiency of practitioners in the use of novel molecular signatures in patient management. In addition, intricate details about disease disparity among different human populations are beginning to emerge. This would facilitate the use of tailor-made novel theranostic methods based on emerging molecular evidences.Conclusion:In this review, we examined the challenges and prospects of using currently available omics-based technologies vis-à-vis oral pathology as well as prompt cancer diagnosis and treatment in a resource limited setting.Keywords:Omics-based, Molecular, Developing world, Oral pathology, Challenges
- Full Text:
- Date Issued: 2017
Written medicines information for South African HIV/AIDS patients: does it enhance understanding of co-trimoxazole therapy?
- Mansoor, Leila E, Dowse, Roslind
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156860 , vital:40059 , https://0-doi.org.wam.seals.ac.za/10.1093/her/cyl039
- Description: Written information to promote patient education is being increasingly recognized as an integral part of quality health care. The main objective of this study was to evaluate the effect of distributing a patient information leaflet (PIL) on knowledge acquisition and recall. Two different PILs were designed for co-trimoxazole tablets: a simple, shorter PIL that incorporated pictograms and text and a text-only PIL that was longer and more complex. Human immunodeficiency virus-positive participants on chronic co-trimoxazole therapy were enrolled from five local primary health care clinics in Grahamstown, South Africa, and were randomly allocated to a Control Group (no PIL), Group A (text-only PIL) or Group B (simple PIL with pictograms).
- Full Text:
- Date Issued: 2007
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156860 , vital:40059 , https://0-doi.org.wam.seals.ac.za/10.1093/her/cyl039
- Description: Written information to promote patient education is being increasingly recognized as an integral part of quality health care. The main objective of this study was to evaluate the effect of distributing a patient information leaflet (PIL) on knowledge acquisition and recall. Two different PILs were designed for co-trimoxazole tablets: a simple, shorter PIL that incorporated pictograms and text and a text-only PIL that was longer and more complex. Human immunodeficiency virus-positive participants on chronic co-trimoxazole therapy were enrolled from five local primary health care clinics in Grahamstown, South Africa, and were randomly allocated to a Control Group (no PIL), Group A (text-only PIL) or Group B (simple PIL with pictograms).
- Full Text:
- Date Issued: 2007
Shopstewards summit - Notice and Agenda
- SACCAWU
- Authors: SACCAWU
- Date: Oct 2007
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/137723 , vital:37553
- Description: Comrades National Office Bearers of SACCAWU, other leadership of the Union at various level, the Wits Regional leadership of SACCAWU, the Shoprite Checkers NSSC NOBs, Officials, esteemed guests and delegates to this Summit, a substructure to the NSSC, I bring you warm and revolutionary greetings on behalf of the Shoprite Checkers NOBs and the entire NSSC and the entire SACCAWU membership. We are indeed honoured that you have all, particularly the SACCAWU NOBs, Officials and Guests, went to great length and sacrifices to ensure that you form part of this historic Summit. It is historic in that it is the only meeting of national competence convened in the year the NSSC turns twenty. Lest we forget, the Shoprite Council was launched in 1987, and has over the years relaunched to match the developments that were taking place within the company as it was growing its brands. Without your presence, we have no doubt that our debates would be poorer, leading to decisions that might in the long run prove inappropriate. You are once more welcome and assured that you are free to participate in the deliberations over the next few days. The Council have seen various onslaughts through the years and survived the iron-fisted resolve of the brutal apartheid regime and the capitalist system in its changing forms. It is the experiences of the time that has moulded numerous Shopstewards to an extent of understanding the necessity of participating within the Union and Federation structures. It is no coincidence that today, this Council has many of its Shopstewards in the CEC of the Union. It is of course worthless to have numbers in such structures if we do not play a positive and constructive role in shaping the direction of the Union. We can only do so if we are really grounded on the traditions of the mass democratic movement and the national democratic revolution.
- Full Text:
- Date Issued: Oct 2007
- Authors: SACCAWU
- Date: Oct 2007
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/137723 , vital:37553
- Description: Comrades National Office Bearers of SACCAWU, other leadership of the Union at various level, the Wits Regional leadership of SACCAWU, the Shoprite Checkers NSSC NOBs, Officials, esteemed guests and delegates to this Summit, a substructure to the NSSC, I bring you warm and revolutionary greetings on behalf of the Shoprite Checkers NOBs and the entire NSSC and the entire SACCAWU membership. We are indeed honoured that you have all, particularly the SACCAWU NOBs, Officials and Guests, went to great length and sacrifices to ensure that you form part of this historic Summit. It is historic in that it is the only meeting of national competence convened in the year the NSSC turns twenty. Lest we forget, the Shoprite Council was launched in 1987, and has over the years relaunched to match the developments that were taking place within the company as it was growing its brands. Without your presence, we have no doubt that our debates would be poorer, leading to decisions that might in the long run prove inappropriate. You are once more welcome and assured that you are free to participate in the deliberations over the next few days. The Council have seen various onslaughts through the years and survived the iron-fisted resolve of the brutal apartheid regime and the capitalist system in its changing forms. It is the experiences of the time that has moulded numerous Shopstewards to an extent of understanding the necessity of participating within the Union and Federation structures. It is no coincidence that today, this Council has many of its Shopstewards in the CEC of the Union. It is of course worthless to have numbers in such structures if we do not play a positive and constructive role in shaping the direction of the Union. We can only do so if we are really grounded on the traditions of the mass democratic movement and the national democratic revolution.
- Full Text:
- Date Issued: Oct 2007
Structure-based analysis of single nucleotide variants in the renin-angiotensinogen complex:
- Brown, David K, Olivier, Sheik Amamuddy, Tastan Bishop, Özlem
- Authors: Brown, David K , Olivier, Sheik Amamuddy , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147994 , vital:38700 , https://doi.org/10.1016/j.gheart.2017.01.006
- Description: The renin-angiotensin system (RAS) plays an important role in regulating blood pressure and controlling sodium levels in the blood. Hyperactivity of this system has been linked to numerous conditions including hypertension, kidney disease, and congestive heart failure. Three classes of drugs have been developed to inhibit RAS. In this study, we provide a structure-based analysis of the effect of single nucleotide variants (SNVs) on the interaction between renin and angiotensinogen with the aim of revealing important residues and potentially damaging variants for further inhibitor design purposes.
- Full Text:
- Date Issued: 2017
- Authors: Brown, David K , Olivier, Sheik Amamuddy , Tastan Bishop, Özlem
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147994 , vital:38700 , https://doi.org/10.1016/j.gheart.2017.01.006
- Description: The renin-angiotensin system (RAS) plays an important role in regulating blood pressure and controlling sodium levels in the blood. Hyperactivity of this system has been linked to numerous conditions including hypertension, kidney disease, and congestive heart failure. Three classes of drugs have been developed to inhibit RAS. In this study, we provide a structure-based analysis of the effect of single nucleotide variants (SNVs) on the interaction between renin and angiotensinogen with the aim of revealing important residues and potentially damaging variants for further inhibitor design purposes.
- Full Text:
- Date Issued: 2017
Optimisation of the emulsion liquid membrane composition and demulsification for rhodium extraction
- Moyo, Francis, Tandlich, Roman
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76743 , vital:30626 , https://doi.org/10.1515/lwr-2015-0002
- Description: This study was aimed at designing an optimised emulsion liquid membrane (ELM) for the extraction of rhodium from precious metal refinery wastewaters. The demulsification process and the structure of the optimised ELM are reported on. Two optimised ELMs were prepared. The first one contained a 30 % solution of toluene in kerosene as diluent with the following concentrations of the ELM components: 30.000 g/L (w/v) polyisobutylene, 10.870 g/L (m/v) of trioctyl amine and 51.001 g/L (m/v) of SPAN 80. The second ELM contained the same diluent, but the concentrations of the other ELM components in it were as follows: 20.000 g/l of polyisobutylene, 10.268 g/l trioctyl amine and 50.024 g/l of SPAN 80. The stripping phase was the same in both optimised ELMs, namely a 2 M solution of HNO3. The stripping phase and the diluent solution were mixed together in ratios of 1:1 and 2:1, respectively. Two methods were used to characterise the microdroplet diameters, i.e. optical microscopy and the Zeta-sizer. For the t-test, the p-value of 0.3018 at 5 % level of significance showed that there was statistically no significant difference in the mean micro-droplet size for 1:2 ELMs containing 20 g/l and 30 g/l of polyisobutylene after 40 minutes of emulsification. The best demulsification results were obtained using the chemical demulsification with polyethylene glycol with molecular weight of 400 g/mol (PEG 400) at 50 ± 1 °C for 24 hours. However, significant carryover of toluene, trioctyl amine and polyethylene glycol into the aqueous phase was observed.
- Full Text:
- Date Issued: 2015
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76743 , vital:30626 , https://doi.org/10.1515/lwr-2015-0002
- Description: This study was aimed at designing an optimised emulsion liquid membrane (ELM) for the extraction of rhodium from precious metal refinery wastewaters. The demulsification process and the structure of the optimised ELM are reported on. Two optimised ELMs were prepared. The first one contained a 30 % solution of toluene in kerosene as diluent with the following concentrations of the ELM components: 30.000 g/L (w/v) polyisobutylene, 10.870 g/L (m/v) of trioctyl amine and 51.001 g/L (m/v) of SPAN 80. The second ELM contained the same diluent, but the concentrations of the other ELM components in it were as follows: 20.000 g/l of polyisobutylene, 10.268 g/l trioctyl amine and 50.024 g/l of SPAN 80. The stripping phase was the same in both optimised ELMs, namely a 2 M solution of HNO3. The stripping phase and the diluent solution were mixed together in ratios of 1:1 and 2:1, respectively. Two methods were used to characterise the microdroplet diameters, i.e. optical microscopy and the Zeta-sizer. For the t-test, the p-value of 0.3018 at 5 % level of significance showed that there was statistically no significant difference in the mean micro-droplet size for 1:2 ELMs containing 20 g/l and 30 g/l of polyisobutylene after 40 minutes of emulsification. The best demulsification results were obtained using the chemical demulsification with polyethylene glycol with molecular weight of 400 g/mol (PEG 400) at 50 ± 1 °C for 24 hours. However, significant carryover of toluene, trioctyl amine and polyethylene glycol into the aqueous phase was observed.
- Full Text:
- Date Issued: 2015
Campaigns Bulletin : Anti-Privatisation Campaign Special Issue
- SAMWU
- Authors: SAMWU
- Date: Mar 1998
- Subjects: SAMWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/113407 , vital:33768
- Description: The SAMWU anti-privatisation campaign goes right to the heart of all members in their role as service providers to the community. Any privatisation of municipal services would mean that people in community not have access to basic services. It would also mean a loss of jobs through retrenchment and restructuring. This has already happened in other parts of the world. Internationally, public sector unions are fighting privatisation. For all these reasons, SAMWU calls on all members to intensify the anti-privatisation campaign! Experiences internationally have shown that privatisation results in increase in tariffs and a decline in quality services. Our communities have never received a quality service under apartheid. Now things will even be worse: under privatisation only those who can afford to pay, will get services. A major political responsibility that confronts SAMWU: we must ensure that we win the struggle against privatisation. We are confident that based on the democratic participation of ‘our gold', SAMWU workers, COSATU and the community we can be victorious.
- Full Text:
- Date Issued: Mar 1998
- Authors: SAMWU
- Date: Mar 1998
- Subjects: SAMWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/113407 , vital:33768
- Description: The SAMWU anti-privatisation campaign goes right to the heart of all members in their role as service providers to the community. Any privatisation of municipal services would mean that people in community not have access to basic services. It would also mean a loss of jobs through retrenchment and restructuring. This has already happened in other parts of the world. Internationally, public sector unions are fighting privatisation. For all these reasons, SAMWU calls on all members to intensify the anti-privatisation campaign! Experiences internationally have shown that privatisation results in increase in tariffs and a decline in quality services. Our communities have never received a quality service under apartheid. Now things will even be worse: under privatisation only those who can afford to pay, will get services. A major political responsibility that confronts SAMWU: we must ensure that we win the struggle against privatisation. We are confident that based on the democratic participation of ‘our gold', SAMWU workers, COSATU and the community we can be victorious.
- Full Text:
- Date Issued: Mar 1998
Sigtuna Think Piece 8: Piecing together conceptual framings for climate change education research in southern African contexts
- Authors: Lotz-Sisitka, Heila
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67378 , vital:29082 , https://www.ajol.info/index.php/sajee/article/view/122808
- Description: publisher version , This think piece considers a range of theoretical and conceptual tools that may assist with the emergence of a research agenda for climate change in education. It considers the conditions that are created by climate change in and for southern African contexts, and then deliberates which contextually related theoretical tools may be useful to frame research questions for climate change education. I consider the educational research implications of adaptation practices, reflexive justice and agency, reflexivity and capability, noting that a climate change education research agenda, not different to a wider reflexive environmental education research agenda dealing with transformative praxis in southern Africa, is essentially a sociologically and historically emergent ‘researching with’ agenda, and is in effect a social learning process. In putting together these conceptual framings for a climate change research agenda in southern Africa, I am interested in exploring how participatory social learning research may strengthen agency and reflexivity (development of capabilities) in response to socio-ecological conditions.
- Full Text:
- Date Issued: 2009
- Authors: Lotz-Sisitka, Heila
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67378 , vital:29082 , https://www.ajol.info/index.php/sajee/article/view/122808
- Description: publisher version , This think piece considers a range of theoretical and conceptual tools that may assist with the emergence of a research agenda for climate change in education. It considers the conditions that are created by climate change in and for southern African contexts, and then deliberates which contextually related theoretical tools may be useful to frame research questions for climate change education. I consider the educational research implications of adaptation practices, reflexive justice and agency, reflexivity and capability, noting that a climate change education research agenda, not different to a wider reflexive environmental education research agenda dealing with transformative praxis in southern Africa, is essentially a sociologically and historically emergent ‘researching with’ agenda, and is in effect a social learning process. In putting together these conceptual framings for a climate change research agenda in southern Africa, I am interested in exploring how participatory social learning research may strengthen agency and reflexivity (development of capabilities) in response to socio-ecological conditions.
- Full Text:
- Date Issued: 2009
A mathematics teacher's response to a dilemma: 'I'm supposed to teach them in English but they don't understand'
- Robertson, Sally-Ann, Graven, Mellony
- Authors: Robertson, Sally-Ann , Graven, Mellony
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148889 , vital:38783 , https://doi.org/10.4102/sajce.v10i1.800
- Description: English is the dominant language in South African schools although it is the home language for less than 10% of the population. Many schools have yet to embrace the Language in Education Policy’s advocacy of additive bilingualism. This has led to a majority of the country’s children learning and being assessed through a language in which they lack proficiency. This article draws on second language teaching and learning theory to make a case for more systematic support for learners’ second language development and for legitimation of use of home language in mathematics classrooms where a different language is the official medium. The article shares empirical data from a South African Grade 4 mathematics teacher’s classroom to illuminate arguments in favour of additive bilingualism.
- Full Text:
- Date Issued: 2020
- Authors: Robertson, Sally-Ann , Graven, Mellony
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148889 , vital:38783 , https://doi.org/10.4102/sajce.v10i1.800
- Description: English is the dominant language in South African schools although it is the home language for less than 10% of the population. Many schools have yet to embrace the Language in Education Policy’s advocacy of additive bilingualism. This has led to a majority of the country’s children learning and being assessed through a language in which they lack proficiency. This article draws on second language teaching and learning theory to make a case for more systematic support for learners’ second language development and for legitimation of use of home language in mathematics classrooms where a different language is the official medium. The article shares empirical data from a South African Grade 4 mathematics teacher’s classroom to illuminate arguments in favour of additive bilingualism.
- Full Text:
- Date Issued: 2020
Comparison between base metals and platinum group metals in nitrogen, M codoped TiO 2 (M= Fe, Cu, Pd, Os) for photocatalytic removal of an organic dye in water
- Kuvarega, Alex T, Mamba, Bhekie B, Krause, Rui W M
- Authors: Kuvarega, Alex T , Mamba, Bhekie B , Krause, Rui W M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125129 , vital:35734 , https://doi.org/10.1155/2014/962102
- Description: The photocatalytic performance of a number of nonmetal and metal codoped TiO2 for the degradation of eosin yellow under simulated solar radiation was investigated. The synthesised materials were characterised by FTIR, Raman spectroscopy, XRD, DRUV-Vis, SEM, and TEM.The N, metal codoped TiO2 containing 0.5 wt.% of the metal consisted mainly of the anatase phase, with a particle size range of 15–28 nm. The particles were largely spherical and shifted the absorption edge well into the visible region. Band gap reduction was more pronounced for the N, PGM codoped TiO2 compared to N, base metal codoped samples. Codoping led to an enhancement in the photocatalytic activity of the materials for the degradation of eosin yellow. N, Pd codoped TiO2 was the most effective photocatalyst (99.9% dye removal) while N, Cu codoped TiO2 showed the least activity (25.5% removal). The mechanism for the photocatalytic enhancement was proposed on the basis of formation of an electron deficient Schottky barrier at the semiconductor-metal interface, which acts as an electron sink and thus retards electron-hole recombination. It was shown that the ability of the photocatalyst to degrade the dye depends on the nature and type of the metal dopant in the codoped TiO2 system.
- Full Text:
- Date Issued: 2014
- Authors: Kuvarega, Alex T , Mamba, Bhekie B , Krause, Rui W M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125129 , vital:35734 , https://doi.org/10.1155/2014/962102
- Description: The photocatalytic performance of a number of nonmetal and metal codoped TiO2 for the degradation of eosin yellow under simulated solar radiation was investigated. The synthesised materials were characterised by FTIR, Raman spectroscopy, XRD, DRUV-Vis, SEM, and TEM.The N, metal codoped TiO2 containing 0.5 wt.% of the metal consisted mainly of the anatase phase, with a particle size range of 15–28 nm. The particles were largely spherical and shifted the absorption edge well into the visible region. Band gap reduction was more pronounced for the N, PGM codoped TiO2 compared to N, base metal codoped samples. Codoping led to an enhancement in the photocatalytic activity of the materials for the degradation of eosin yellow. N, Pd codoped TiO2 was the most effective photocatalyst (99.9% dye removal) while N, Cu codoped TiO2 showed the least activity (25.5% removal). The mechanism for the photocatalytic enhancement was proposed on the basis of formation of an electron deficient Schottky barrier at the semiconductor-metal interface, which acts as an electron sink and thus retards electron-hole recombination. It was shown that the ability of the photocatalyst to degrade the dye depends on the nature and type of the metal dopant in the codoped TiO2 system.
- Full Text:
- Date Issued: 2014
Presidential Address
- Date: 1992-01
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/32355 , vital:32026 , Box File 7
- Description: Presidential Addresses were delivered at each Annual conference of the New Unity Movement. This collection, though incomplete, has 18 items ranging from 1989 to 2013.
- Full Text: false
- Date Issued: 1992-01
- Date: 1992-01
- Subjects: Government, Resistance to -- South Africa , South Africa -- History -- 20th century , South Africa -- Politics and government
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10948/32355 , vital:32026 , Box File 7
- Description: Presidential Addresses were delivered at each Annual conference of the New Unity Movement. This collection, though incomplete, has 18 items ranging from 1989 to 2013.
- Full Text: false
- Date Issued: 1992-01
Rhodes University 1985 Graduation Ceremonies Address
- Authors: Henderson, Derek Scott
- Date: 1985
- Language: English
- Type: text
- Identifier: vital:7487 , http://hdl.handle.net/10962/d1018364
- Full Text:
- Date Issued: 1985
- Authors: Henderson, Derek Scott
- Date: 1985
- Language: English
- Type: text
- Identifier: vital:7487 , http://hdl.handle.net/10962/d1018364
- Full Text:
- Date Issued: 1985
Gully erosion as a mechanism for wetland formation: an examination of two contrasting landscapes
- Pulley, Simon, Ellery, William F N, Lagesse, Juliette V, Schlegel, P Philippa, McNamara, Shaun J
- Authors: Pulley, Simon , Ellery, William F N , Lagesse, Juliette V , Schlegel, P Philippa , McNamara, Shaun J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144410 , vital:38343 , DOI: 10.1002/ldr.2972
- Description: Wetlands occupy broad, gently sloping valleys characterised by net deposition. Consequently, gully incision is viewed as an agent of wetland destruction. However, little attention has been given to the role of gullies in natural wetland formation. This paper determines if gully cutting and filling cycles have led to wetland formation in both an extant eroding wetland and a semi‐arid environment that once supported wetlands. At both sites, the valley fill was investigated to identify infilled gullies, and a 14C date was obtained from the gully fill.
- Full Text:
- Date Issued: 2018
- Authors: Pulley, Simon , Ellery, William F N , Lagesse, Juliette V , Schlegel, P Philippa , McNamara, Shaun J
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144410 , vital:38343 , DOI: 10.1002/ldr.2972
- Description: Wetlands occupy broad, gently sloping valleys characterised by net deposition. Consequently, gully incision is viewed as an agent of wetland destruction. However, little attention has been given to the role of gullies in natural wetland formation. This paper determines if gully cutting and filling cycles have led to wetland formation in both an extant eroding wetland and a semi‐arid environment that once supported wetlands. At both sites, the valley fill was investigated to identify infilled gullies, and a 14C date was obtained from the gully fill.
- Full Text:
- Date Issued: 2018
The Educational Journal
- Date: 2002-08
- Subjects: Education – South Africa , South Africa – Economic conditions , South Africa – Social conditions
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/38409 , vital:34743 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa. From the 2000s, the journal was published by the National Union of Public Service and Allied Workers (NUPSAW), a trade union formed in August 1998 from the amalgamation of militant and moderate trade unions and also operated in the education sphere.
- Full Text: false
- Date Issued: 2002-08
- Date: 2002-08
- Subjects: Education – South Africa , South Africa – Economic conditions , South Africa – Social conditions
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/38409 , vital:34743 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa. From the 2000s, the journal was published by the National Union of Public Service and Allied Workers (NUPSAW), a trade union formed in August 1998 from the amalgamation of militant and moderate trade unions and also operated in the education sphere.
- Full Text: false
- Date Issued: 2002-08
Rhodes University Graduation Ceremony 1964
- Authors: Rhodes University
- Date: 1964
- Language: English
- Type: text
- Identifier: vital:8098 , http://hdl.handle.net/10962/d1004426
- Description: Rhodes University Graduation Ceremony on Saturday 11 April 1964 at 10:30 a.m. in the University Great Hall.
- Full Text:
- Date Issued: 1964
- Authors: Rhodes University
- Date: 1964
- Language: English
- Type: text
- Identifier: vital:8098 , http://hdl.handle.net/10962/d1004426
- Description: Rhodes University Graduation Ceremony on Saturday 11 April 1964 at 10:30 a.m. in the University Great Hall.
- Full Text:
- Date Issued: 1964
The Educational Journal
- Date: 1976-09
- Subjects: Education –- South Africa , South Africa -- Politics and government , Government, Resistance to -- South Africa
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/35926 , vital:33862 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa.
- Full Text: false
- Date Issued: 1976-09
- Date: 1976-09
- Subjects: Education –- South Africa , South Africa -- Politics and government , Government, Resistance to -- South Africa
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/35926 , vital:33862 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa.
- Full Text: false
- Date Issued: 1976-09
Studies on the Zoarcidae (Teleostei: Perciformes) of the southern hemisphere, VI: Review of the genus Ophthalmolycus Regan, 1913, with description of a new species from Chile
- Anderson, M Eric, J.L.B. Smith Institute of Ichthyology
- Authors: Anderson, M Eric , J.L.B. Smith Institute of Ichthyology
- Date: 1992-04
- Subjects: Perciformes , Osteichthyes , Zoarcidae
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70403 , vital:29652 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 53 , The eelpout genus Ophthalmolycus Regan, 1913 is reviewed and includes a new species, O. chilensis, the sixth for the genus. Ophthalmolycus conorhynchus (Garman, 1899) is redescribed from the damaged syntypes and a more recently collected specimen. A key to all species of the genus is included. Expanded diagnoses are provided for the four other species of Ophthalmolycus, recently described elsewhere.
- Full Text:
- Date Issued: 1992-04
- Authors: Anderson, M Eric , J.L.B. Smith Institute of Ichthyology
- Date: 1992-04
- Subjects: Perciformes , Osteichthyes , Zoarcidae
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70403 , vital:29652 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 53 , The eelpout genus Ophthalmolycus Regan, 1913 is reviewed and includes a new species, O. chilensis, the sixth for the genus. Ophthalmolycus conorhynchus (Garman, 1899) is redescribed from the damaged syntypes and a more recently collected specimen. A key to all species of the genus is included. Expanded diagnoses are provided for the four other species of Ophthalmolycus, recently described elsewhere.
- Full Text:
- Date Issued: 1992-04
The Educational Journal
- Date: 1997-06
- Subjects: Education –- South Africa , South Africa -- Politics and government , Government, Resistance to -- South Africa
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/38169 , vital:34407 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa.
- Full Text: false
- Date Issued: 1997-06
- Date: 1997-06
- Subjects: Education –- South Africa , South Africa -- Politics and government , Government, Resistance to -- South Africa
- Language: English
- Type: text , Article
- Identifier: http://hdl.handle.net/10948/38169 , vital:34407 , Bulk File 7
- Description: The Educational Journal was the official organ of the Teachers' League of South Africa and focussed on education within the context of a racialized South Africa.
- Full Text: false
- Date Issued: 1997-06