'Meaningful engagement’: Towards a language rights paradigm for effective language policy implementation
- Docrat, Zakeera, Kaschula, Russell H
- Authors: Docrat, Zakeera , Kaschula, Russell H
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/174812 , vital:42512 , https://doi.org/10.1080/02572117.2015.1056455
- Description: This article aims to develop the concept of ‘meaningful engagement’ in terms of the contemporary language policy implementation framework in South Africa. By exploring the current language policies, implementation and the current lack of effectiveness, the authors offer a new implementation focus drawn from the legal concept of ‘meaningful engagement’. ‘Meaningful engagement’ is a concept within the socio-economic rights sphere. This article expands and advances the concept within a language policy framework. Against the enabling legislative environment created by the Use of Official Languages Act 12 of 2012 and the overarching Constitutional framework which embeds the rights of all official languages, ‘meaningful engagement’ is developed and applied to selected language policies and practices.
- Full Text:
- Date Issued: 2015
- Authors: Docrat, Zakeera , Kaschula, Russell H
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/174812 , vital:42512 , https://doi.org/10.1080/02572117.2015.1056455
- Description: This article aims to develop the concept of ‘meaningful engagement’ in terms of the contemporary language policy implementation framework in South Africa. By exploring the current language policies, implementation and the current lack of effectiveness, the authors offer a new implementation focus drawn from the legal concept of ‘meaningful engagement’. ‘Meaningful engagement’ is a concept within the socio-economic rights sphere. This article expands and advances the concept within a language policy framework. Against the enabling legislative environment created by the Use of Official Languages Act 12 of 2012 and the overarching Constitutional framework which embeds the rights of all official languages, ‘meaningful engagement’ is developed and applied to selected language policies and practices.
- Full Text:
- Date Issued: 2015
'Taking language issues to the people': language development in context.
- Authors: Wright, Laurence
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:77243 , https://doi.org/10.2989/16073610209486320
- Description: This paper represents a prologue to a taxonomy of participatory language development strategies, one which argues that some re-orientation of thinking about Language Planning is needed for South Africa's linguistic 'renaissance' to make progress. The immediate institutional argument is for the creation of modestly equipped and staffed Language Development Centres easily accessible to the speech communities responsible for the maintenance and development of their languages, particularly the nine official PMLs (Previously Marginalised Languages), but also the dialects. The paper sets out to suggest why such centres may be necessary if we are serious about creating conditions in which the PMLs can be successfully developed without thoughtlessly damaging South Africa's linguistic diversity.
- Full Text:
- Date Issued: 2002
- Authors: Wright, Laurence
- Date: 2002
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:77243 , https://doi.org/10.2989/16073610209486320
- Description: This paper represents a prologue to a taxonomy of participatory language development strategies, one which argues that some re-orientation of thinking about Language Planning is needed for South Africa's linguistic 'renaissance' to make progress. The immediate institutional argument is for the creation of modestly equipped and staffed Language Development Centres easily accessible to the speech communities responsible for the maintenance and development of their languages, particularly the nine official PMLs (Previously Marginalised Languages), but also the dialects. The paper sets out to suggest why such centres may be necessary if we are serious about creating conditions in which the PMLs can be successfully developed without thoughtlessly damaging South Africa's linguistic diversity.
- Full Text:
- Date Issued: 2002
A case study on the health risks related to flood disasters in South Africa
- Tandlich, Roman, Ncube, Mbonisi, Khamanga, Sandile M, Zuma, Bongumusa M
- Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
- Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
- Full Text: false
- Date Issued: 2016
- Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
- Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
- Full Text: false
- Date Issued: 2016
A comparison of three models used to determine water fluxes over the Albany Thicket, Eastern Cape, South Africa:
- Palmer, Anthony R, Ezenne, G I, Choruma, D J, Gwate, O, Mantel, Sukhmani K, Tanner, Jane L
- Authors: Palmer, Anthony R , Ezenne, G I , Choruma, D J , Gwate, O , Mantel, Sukhmani K , Tanner, Jane L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150047 , vital:38934 , https://doi.org/10.1016/j.agrformet.2020.107984
- Description: The Albany Thicket (AT) biome contains outstanding global biodiversity as well as the potential to achieve carbon credits associated with water-efficient Crasslucean acid metabolism (CAM). Understanding the water fluxes in the AT is crucial to determining carbon (C) sequestration rates and water-use efficiency. Despite large variation in water fluxes across the AT, only a few studies have been conducted in this region with their results validated against short periods of observed data. This study aims to evaluate three models of water fluxes over AT against data from an eddy covariance (EC) system active from October 2015 to May 2018. ET was modelled using the BioGeoChemistry Management (BGC-MAN) model, a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely-sensed product (MOD16), and their results compared with that from the EC system.
- Full Text:
- Date Issued: 2020
- Authors: Palmer, Anthony R , Ezenne, G I , Choruma, D J , Gwate, O , Mantel, Sukhmani K , Tanner, Jane L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150047 , vital:38934 , https://doi.org/10.1016/j.agrformet.2020.107984
- Description: The Albany Thicket (AT) biome contains outstanding global biodiversity as well as the potential to achieve carbon credits associated with water-efficient Crasslucean acid metabolism (CAM). Understanding the water fluxes in the AT is crucial to determining carbon (C) sequestration rates and water-use efficiency. Despite large variation in water fluxes across the AT, only a few studies have been conducted in this region with their results validated against short periods of observed data. This study aims to evaluate three models of water fluxes over AT against data from an eddy covariance (EC) system active from October 2015 to May 2018. ET was modelled using the BioGeoChemistry Management (BGC-MAN) model, a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely-sensed product (MOD16), and their results compared with that from the EC system.
- Full Text:
- Date Issued: 2020
A Flexible Approach for the Application of Immersive Audio to an Installation Performance:
- Devonport, Sean, Foss, Richard
- Authors: Devonport, Sean , Foss, Richard
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426720 , vital:72385 , https://www.isea-international.org/symposia/1988-2022/
- Description: This paper investigates the use of the ImmerGo spatial audio system and Ethernet AVB as a platform for the creation and deployment of immersive audio content. An analysis of Ethernet AVB and ImmerGo’s features is given. This is followed by a practical implementation of ImmerGo within an installation setting of a choreographed performance. This approach provided key features such as user control from a mobile device to render positions of audio tracks and control DAW transport. The Ethernet AVB network allowed for real-time synchronized audio streaming, audio device interoperability, distributed endpoint processing and simple audio routing schemes.
- Full Text:
- Date Issued: 2018
- Authors: Devonport, Sean , Foss, Richard
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426720 , vital:72385 , https://www.isea-international.org/symposia/1988-2022/
- Description: This paper investigates the use of the ImmerGo spatial audio system and Ethernet AVB as a platform for the creation and deployment of immersive audio content. An analysis of Ethernet AVB and ImmerGo’s features is given. This is followed by a practical implementation of ImmerGo within an installation setting of a choreographed performance. This approach provided key features such as user control from a mobile device to render positions of audio tracks and control DAW transport. The Ethernet AVB network allowed for real-time synchronized audio streaming, audio device interoperability, distributed endpoint processing and simple audio routing schemes.
- Full Text:
- Date Issued: 2018
A laterally extensive geochemical discontinuity in the subcontinental Gondwana Lithosphere
- Erlank, Anthony J, Duncan, Andrew R, Marsh, Julian S, Sweeney, R J, Hawkesworth, C J, Milner, Simon C, Miller, R McG, Rogers, N W
- Authors: Erlank, Anthony J , Duncan, Andrew R , Marsh, Julian S , Sweeney, R J , Hawkesworth, C J , Milner, Simon C , Miller, R McG , Rogers, N W
- Date: 1988
- Language: English
- Type: text , abstracts
- Identifier: http://hdl.handle.net/10962/131678 , vital:36710
- Description: Cox et al. (1967) first delineated the existence of two major geochemical provinces in the Karoo basalts of southern Africa. Tholeiitic basalts in Zimbabwe are highly enriched in incompatible trace elements and constitute the "northern province". In contrast, basalts from Lesotho and from the southern segment of the Lebombo monocline have lower or “normal” abundances of these elements and were regarded as a "southern province'. Recent work has established that this change in composition takes place relatively rapidly in the Central Lebombo.
- Full Text:
- Date Issued: 1988
- Authors: Erlank, Anthony J , Duncan, Andrew R , Marsh, Julian S , Sweeney, R J , Hawkesworth, C J , Milner, Simon C , Miller, R McG , Rogers, N W
- Date: 1988
- Language: English
- Type: text , abstracts
- Identifier: http://hdl.handle.net/10962/131678 , vital:36710
- Description: Cox et al. (1967) first delineated the existence of two major geochemical provinces in the Karoo basalts of southern Africa. Tholeiitic basalts in Zimbabwe are highly enriched in incompatible trace elements and constitute the "northern province". In contrast, basalts from Lesotho and from the southern segment of the Lebombo monocline have lower or “normal” abundances of these elements and were regarded as a "southern province'. Recent work has established that this change in composition takes place relatively rapidly in the Central Lebombo.
- Full Text:
- Date Issued: 1988
A missing link in the estuarine nitrogen cycle?: coupled nitrification-denitrification mediated by suspended particulate matter
- Zhu, Weijing, Wang, Cheng, Hill, Jaclyn M, He, Yangyang, Tao, Bangyi, Mao, Zhihua, Wu, Weixiang
- Authors: Zhu, Weijing , Wang, Cheng , Hill, Jaclyn M , He, Yangyang , Tao, Bangyi , Mao, Zhihua , Wu, Weixiang
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68368 , vital:29244 , https://0-doi.org.wam.seals.ac.za/10.1038/s41598-018-20688-4
- Description: In estuarine and coastal ecosystems, the majority of previous studies have considered coupled nitrification-denitrification (CND) processes to be exclusively sediment based, with little focus onsuspended particulate matter (SPM) in the water column. Here, we present evidence of CND processes in the water column of Hangzhou Bay, one of the largest macrotidal embayments in the world.
- Full Text:
- Date Issued: 2018
- Authors: Zhu, Weijing , Wang, Cheng , Hill, Jaclyn M , He, Yangyang , Tao, Bangyi , Mao, Zhihua , Wu, Weixiang
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68368 , vital:29244 , https://0-doi.org.wam.seals.ac.za/10.1038/s41598-018-20688-4
- Description: In estuarine and coastal ecosystems, the majority of previous studies have considered coupled nitrification-denitrification (CND) processes to be exclusively sediment based, with little focus onsuspended particulate matter (SPM) in the water column. Here, we present evidence of CND processes in the water column of Hangzhou Bay, one of the largest macrotidal embayments in the world.
- Full Text:
- Date Issued: 2018
A new broom sweeps clean: the economic and cultural value of grass brooms in the Eastern Cape Province, South Africa
- Cocks, Michelle L, Dold, Anthony P
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141382 , vital:37967 , DOI: 10.1080/14728028.2004.9752477
- Description: In southern Africa over the last twenty years, much attention has been given to the importance of NTFPs for rural livelihoods through their household consumption and sale. They have been classified as having either subsistence consumption or commercial values. These values are mostly related to their utilitarian functions, but recent studies show that NTFPs also hold strong cultural functions. Such cultural functions can play a role in both rural and urban livelihoods; consequently the values of NTFPs may be related to both utilitarian and cultural functions. This paper demonstrates the cultural functions of grass brooms in urban areas in South Africa and the impact of their trade on income generation in rural areas, and discusses the concept of culture as a significant factor in the understanding of the role of NTFPs in livelihoods, and their values.
- Full Text:
- Date Issued: 2012
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141382 , vital:37967 , DOI: 10.1080/14728028.2004.9752477
- Description: In southern Africa over the last twenty years, much attention has been given to the importance of NTFPs for rural livelihoods through their household consumption and sale. They have been classified as having either subsistence consumption or commercial values. These values are mostly related to their utilitarian functions, but recent studies show that NTFPs also hold strong cultural functions. Such cultural functions can play a role in both rural and urban livelihoods; consequently the values of NTFPs may be related to both utilitarian and cultural functions. This paper demonstrates the cultural functions of grass brooms in urban areas in South Africa and the impact of their trade on income generation in rural areas, and discusses the concept of culture as a significant factor in the understanding of the role of NTFPs in livelihoods, and their values.
- Full Text:
- Date Issued: 2012
A new species of Bothus (Pleuronectiformes: Bothidae) from Mozambique
- Hensley, Dannie A, J.L.B. Smith Institute of Ichthyology
- Authors: Hensley, Dannie A , J.L.B. Smith Institute of Ichthyology
- Date: 1997-02
- Subjects: Fishes -- Mozambique
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70976 , vital:29767 , 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. 58 , Bothus swio is described based on one adult male specimen collected off the coast of Mozambique. Males of this species appear to differ from all known congeners because of their narrow interobital region. Other characters useful for its identification are lack of ocular appendages, relative positions of the anterior margins of the eyes, number of lateral-line scales, length and colour pattern of the ocular-side pectoral fin, lack of orbital spines, dorsal- and anal-fin ray counts, and lack of colour pattern on the blind side. Bothus swio most closely resembles B. pantherinus and B. tricirrhitus.
- Full Text:
- Date Issued: 1997-02
- Authors: Hensley, Dannie A , J.L.B. Smith Institute of Ichthyology
- Date: 1997-02
- Subjects: Fishes -- Mozambique
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70976 , vital:29767 , 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. 58 , Bothus swio is described based on one adult male specimen collected off the coast of Mozambique. Males of this species appear to differ from all known congeners because of their narrow interobital region. Other characters useful for its identification are lack of ocular appendages, relative positions of the anterior margins of the eyes, number of lateral-line scales, length and colour pattern of the ocular-side pectoral fin, lack of orbital spines, dorsal- and anal-fin ray counts, and lack of colour pattern on the blind side. Bothus swio most closely resembles B. pantherinus and B. tricirrhitus.
- Full Text:
- Date Issued: 1997-02
A panacea for public participation during Covid-19 and beyond in Matjhabeng Local Municipality
- Authors: Mofolo, Malefetsane
- Date: 2021-08-18
- Subjects: Mthatha Research and Innovation Day , COVID-19 Pandemic, 2020-
- Language: English
- Type: lecture , text
- Identifier: http://hdl.handle.net/11260/6295 , vital:45356
- Description: Since the inception of Covid-19 in 2020 in South Africa and the subsequent lockdown levels that were introduced in order to mitigate the effects of this pandemic, public participation in municipalities has experienced a serious knock. Public participation forms the most important legislative principle for good governance in the South African government. While,the literature is showing that Covid-19 has affected the South African public sector in numerous ways, the tension that was created by the challenges inclined to public participation in the South African municipalities during the pandemic has not gained much attention. Apparently,communities were not even aware of the measures that were introduced to conduct public participation during this period of Covid19.
- Full Text:
- Date Issued: 2021-08-18
- Authors: Mofolo, Malefetsane
- Date: 2021-08-18
- Subjects: Mthatha Research and Innovation Day , COVID-19 Pandemic, 2020-
- Language: English
- Type: lecture , text
- Identifier: http://hdl.handle.net/11260/6295 , vital:45356
- Description: Since the inception of Covid-19 in 2020 in South Africa and the subsequent lockdown levels that were introduced in order to mitigate the effects of this pandemic, public participation in municipalities has experienced a serious knock. Public participation forms the most important legislative principle for good governance in the South African government. While,the literature is showing that Covid-19 has affected the South African public sector in numerous ways, the tension that was created by the challenges inclined to public participation in the South African municipalities during the pandemic has not gained much attention. Apparently,communities were not even aware of the measures that were introduced to conduct public participation during this period of Covid19.
- Full Text:
- Date Issued: 2021-08-18
A preliminary study of minimal-contention locks
- Machanick, Philip, Mbiyavanga, Mamana
- Authors: Machanick, Philip , Mbiyavanga, Mamana
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439093 , vital:73544 , https://doi.org/10.1145/3278681.3278713
- Description: As multicore CPUs become more common, scalable synchronization primitives have wider use and ideas previously used in large-scale computation are worth re-opening for wider use. In this paper I explore one approach to scalable synchronization, a minimal-contention lock (M-lock). The key idea is to avoid spinning on a global variable but instead for each blocked task (process or thread) to spin on a local lock representing the task that immediately preceded it in attempting to acquire the lock. This creates an ordering based on the order in which tasks attempt to acquire the lock, preventing starvation. The only globally shared variable is a pointer to the next local lock to be contended for. Each contending task swaps the value of this pointer for a pointer to its own variable. It spins on the variable previously pointed to by the global pointer. Each waiting task spins on a lock only seen by itself and the owner of that lock variable. While a task is spinning, the lock variable can be held in its local cache until invalidated by the lock owner when it unsets the lock. Consequently, the amount of bus traffic is considerably less than with a spinlock, which has the pernicious feature that the task releasing the lock is delayed by all the other bus traffic arising from contention for the lock. An MCS lock has similar properties but is more complicated and requires more memory contention-causing operations. This paper outlines the design of the M-lock and provides a preliminary performance analysis.
- Full Text:
- Date Issued: 2018
- Authors: Machanick, Philip , Mbiyavanga, Mamana
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/439093 , vital:73544 , https://doi.org/10.1145/3278681.3278713
- Description: As multicore CPUs become more common, scalable synchronization primitives have wider use and ideas previously used in large-scale computation are worth re-opening for wider use. In this paper I explore one approach to scalable synchronization, a minimal-contention lock (M-lock). The key idea is to avoid spinning on a global variable but instead for each blocked task (process or thread) to spin on a local lock representing the task that immediately preceded it in attempting to acquire the lock. This creates an ordering based on the order in which tasks attempt to acquire the lock, preventing starvation. The only globally shared variable is a pointer to the next local lock to be contended for. Each contending task swaps the value of this pointer for a pointer to its own variable. It spins on the variable previously pointed to by the global pointer. Each waiting task spins on a lock only seen by itself and the owner of that lock variable. While a task is spinning, the lock variable can be held in its local cache until invalidated by the lock owner when it unsets the lock. Consequently, the amount of bus traffic is considerably less than with a spinlock, which has the pernicious feature that the task releasing the lock is delayed by all the other bus traffic arising from contention for the lock. An MCS lock has similar properties but is more complicated and requires more memory contention-causing operations. This paper outlines the design of the M-lock and provides a preliminary performance analysis.
- Full Text:
- Date Issued: 2018
A probabilistic movement model for shortest path formation in virtual ant-like agents
- Chibaya, Colin, Bangay, Shaun D
- Authors: Chibaya, Colin , Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433125 , vital:72945 , https://doi.org/10.1145/1292491.1292493
- Description: We propose a probabilistic movement model for controlling ant-like agents foraging between two points. Such agents are all identical, simple, autonomous and can only communicate indirectly through the environment. These agents secrete two types of pheromone, one to mark trails towards the goal and another to mark trails back to the starting point. Three pheromone perception strategies are proposed (Strategy A, B and C). Agents that use strategy A perceive the desirability of a neighbouring location as the difference between levels of attractive and repulsive pheromone in that location. With strategy B, agents perceive the desirability of a location as the quotient of levels of attractive and repulsive pheromone. Agents using strategy C determine the product of the levels of attractive pheromone with the complement of levels of repulsive pheromone. We conduct experiments to confirm directionality as emergent property of trails formed by agents that use each strategy. In addition, we compare path formation speed and the quality of the formed path under changes in the environment. We also investigate each strategy's robustness in environments that contain obstacles. Finally, we investigate how adaptive each strategy is when obstacles are eventually removed from the scene and find that the best strategy of these three is strategy A. Such a strategy provides useful guidelines to researchers in further applications of swarm intelligence metaphors for complex problem solving.
- Full Text:
- Date Issued: 2007
- Authors: Chibaya, Colin , Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433125 , vital:72945 , https://doi.org/10.1145/1292491.1292493
- Description: We propose a probabilistic movement model for controlling ant-like agents foraging between two points. Such agents are all identical, simple, autonomous and can only communicate indirectly through the environment. These agents secrete two types of pheromone, one to mark trails towards the goal and another to mark trails back to the starting point. Three pheromone perception strategies are proposed (Strategy A, B and C). Agents that use strategy A perceive the desirability of a neighbouring location as the difference between levels of attractive and repulsive pheromone in that location. With strategy B, agents perceive the desirability of a location as the quotient of levels of attractive and repulsive pheromone. Agents using strategy C determine the product of the levels of attractive pheromone with the complement of levels of repulsive pheromone. We conduct experiments to confirm directionality as emergent property of trails formed by agents that use each strategy. In addition, we compare path formation speed and the quality of the formed path under changes in the environment. We also investigate each strategy's robustness in environments that contain obstacles. Finally, we investigate how adaptive each strategy is when obstacles are eventually removed from the scene and find that the best strategy of these three is strategy A. Such a strategy provides useful guidelines to researchers in further applications of swarm intelligence metaphors for complex problem solving.
- Full Text:
- Date Issued: 2007
A ring-closing metathesis approach to eight-membered benzannelated scaffolds and subsequent internal alkene isomerizations
- Taher, Abu, Aderibigbe, Blessing A, Morgans, Garreth L, Madeley, Lee G, Khanye, Setshaba D, Van der Westhuizen, Leandi, Fernandes, Manuel A, Smith, Vincent J, Michael, Joseph P, Green, Ivan R, Van Otterlo, Willem A L
- Authors: Taher, Abu , Aderibigbe, Blessing A , Morgans, Garreth L , Madeley, Lee G , Khanye, Setshaba D , Van der Westhuizen, Leandi , Fernandes, Manuel A , Smith, Vincent J , Michael, Joseph P , Green, Ivan R , Van Otterlo, Willem A L
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66252 , vital:28925 , https://doi.org/10.1016/j.tet.2012.12.043
- Description: publisher version , A set of eight-membered benzannelated heterocycles containing two heteroatoms (O,O, NR,NR and O,NR where R=protecting group) was synthesized by ring-closing metathesis from the corresponding ortho-bis-allyl precursors. In this manner, 7-methoxy-2,5-dihydro-1,6-benzodioxocine, 1,2,5,6-tetrahydro-1,6-benzodiazocines, 5,6-dihydro-2H-1,6-benzoxazocines and 5,6,9,10-tetrahydropyrido[2,3-b][1,4]diazocine were synthesized. A number of these compounds were then treated with the catalyst [RuClH(CO)(PPh3)3] to facilitate isomerization of the alkene into conjugation with the heteroatoms in the eight-membered ring. Quite surprisingly, an equal ratio of regioisomers was obtained, even if the heteroatoms were different.
- Full Text: false
- Date Issued: 2013
- Authors: Taher, Abu , Aderibigbe, Blessing A , Morgans, Garreth L , Madeley, Lee G , Khanye, Setshaba D , Van der Westhuizen, Leandi , Fernandes, Manuel A , Smith, Vincent J , Michael, Joseph P , Green, Ivan R , Van Otterlo, Willem A L
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66252 , vital:28925 , https://doi.org/10.1016/j.tet.2012.12.043
- Description: publisher version , A set of eight-membered benzannelated heterocycles containing two heteroatoms (O,O, NR,NR and O,NR where R=protecting group) was synthesized by ring-closing metathesis from the corresponding ortho-bis-allyl precursors. In this manner, 7-methoxy-2,5-dihydro-1,6-benzodioxocine, 1,2,5,6-tetrahydro-1,6-benzodiazocines, 5,6-dihydro-2H-1,6-benzoxazocines and 5,6,9,10-tetrahydropyrido[2,3-b][1,4]diazocine were synthesized. A number of these compounds were then treated with the catalyst [RuClH(CO)(PPh3)3] to facilitate isomerization of the alkene into conjugation with the heteroatoms in the eight-membered ring. Quite surprisingly, an equal ratio of regioisomers was obtained, even if the heteroatoms were different.
- Full Text: false
- Date Issued: 2013
A successful cognitive-behavioural intervention that failed : a case study of adolescent conduct disorder at a school for the disadvantaged
- Mashalaba, Eugenia D, Edwards, David J A
- Authors: Mashalaba, Eugenia D , Edwards, David J A
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6273 , http://hdl.handle.net/10962/d1008273
- Description: Conduct Disorder (CD) is a widespread problem in southern Africa. The aim of the study was to design, implement and evaluate a multi-modal cognitive-behavioural intervention based on treatments developed overseas, in order to investigate whether this approach can be transported to a South African school for deprived children. The target adolescent had a history of severely disruptive behaviour and was facing expulsion from a shelter for homeless children and his school. A thorough assessment served as the basis for a case formulation and treatment plan. Intervention included 23 individual sessions focussing on bereavement and the learning of self-control skills and prosocial behaviours, as well as contingency management training for school and shelter staff. Progress was tracked with a behaviour checklist completed daily by the teacher and regular interviews with school and shelter staff. After four months, the disruptive behaviour was eliminated. However, he was involved in stealing with some other learners and expelled anyway. Nevertheless the case study provides evidence for the transportability of the cognitive-behavioural approach to this kind of setting and documents the way in which a comprehensive intervention can be tailored to the needs of a child with a severely deprived background and little social support.
- Full Text:
- Date Issued: 2005
- Authors: Mashalaba, Eugenia D , Edwards, David J A
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6273 , http://hdl.handle.net/10962/d1008273
- Description: Conduct Disorder (CD) is a widespread problem in southern Africa. The aim of the study was to design, implement and evaluate a multi-modal cognitive-behavioural intervention based on treatments developed overseas, in order to investigate whether this approach can be transported to a South African school for deprived children. The target adolescent had a history of severely disruptive behaviour and was facing expulsion from a shelter for homeless children and his school. A thorough assessment served as the basis for a case formulation and treatment plan. Intervention included 23 individual sessions focussing on bereavement and the learning of self-control skills and prosocial behaviours, as well as contingency management training for school and shelter staff. Progress was tracked with a behaviour checklist completed daily by the teacher and regular interviews with school and shelter staff. After four months, the disruptive behaviour was eliminated. However, he was involved in stealing with some other learners and expelled anyway. Nevertheless the case study provides evidence for the transportability of the cognitive-behavioural approach to this kind of setting and documents the way in which a comprehensive intervention can be tailored to the needs of a child with a severely deprived background and little social support.
- Full Text:
- Date Issued: 2005
A Unified Architecture For Automatic Software Updates
- White, Dominic, Irwin, Barry V W
- Authors: White, Dominic , Irwin, Barry V W
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428800 , vital:72537 , https://citeseerx.ist.psu.edu/document?repid=rep1type=pdfdoi=6e1cd9269a0c5532faf7a23f82995fcfa39e59bd
- Description: This paper attempts to address the issue of hardening the internal secu-rity of an organisation’s network by easing its patch management. Tradi-tionally security has been modeled on a" hard outer shell" approach, with a firewall protecting the otherwise vulnerable internal network. With the advent of worms using such techniques as social engineering to by-pass the organisational firewall and installing trojans, this approach is no longer sufficient. As a result of these new attacks, emphasis should be placed on improving the security of the internal network. Most research agrees that prompt patching of security vulnerabilities would significantly reduce the vulnerability of these machines. However, this requires sys-tem administrators not only to keep abreast of the flood of patches, but to ensure they are deployed to every machine, in what could be a very large network. These difficulties are worsened by problems the patches themselves often create. This is a difficult task and the failure of system administrators to perform it is echoed in the recent spate of worm at-tacks, with some taking advantage of vulnerabilities for which patches had been released up to six months earlier.
- Full Text:
- Date Issued: 2004
- Authors: White, Dominic , Irwin, Barry V W
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428800 , vital:72537 , https://citeseerx.ist.psu.edu/document?repid=rep1type=pdfdoi=6e1cd9269a0c5532faf7a23f82995fcfa39e59bd
- Description: This paper attempts to address the issue of hardening the internal secu-rity of an organisation’s network by easing its patch management. Tradi-tionally security has been modeled on a" hard outer shell" approach, with a firewall protecting the otherwise vulnerable internal network. With the advent of worms using such techniques as social engineering to by-pass the organisational firewall and installing trojans, this approach is no longer sufficient. As a result of these new attacks, emphasis should be placed on improving the security of the internal network. Most research agrees that prompt patching of security vulnerabilities would significantly reduce the vulnerability of these machines. However, this requires sys-tem administrators not only to keep abreast of the flood of patches, but to ensure they are deployed to every machine, in what could be a very large network. These difficulties are worsened by problems the patches themselves often create. This is a difficult task and the failure of system administrators to perform it is echoed in the recent spate of worm at-tacks, with some taking advantage of vulnerabilities for which patches had been released up to six months earlier.
- Full Text:
- Date Issued: 2004
A watershed study on genetic diversity phylogenetic analysis of the Platypleura plumosa (Hemiptera Cicadidae) complex reveals catchment-specific lineages
- Price, Benjamin W, Barker, Nigel P, Villet, Martin H
- Authors: Price, Benjamin W , Barker, Nigel P , Villet, Martin H
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441711 , vital:73909 , https://doi.org/10.1016/j.ympev.2009.10.011
- Description: Historical biogeography studies have at their disposal a small suite of vicariance models to explain genetic differentiation within and between species. One of these processes involves the role of river catchments and their associated watersheds, in driving diversification and is applicable to both aquatic and terrestrial organisms. Although the idea of catchments structuring the genetic history of aquatic organisms is reasonably well understood, their effect on terrestrial organisms has largely been overlooked, with relevant studies being limited in scope. South Africa presents a perfect test-bed for elucidating this mechanism of diversification due to its rich biodiversity, range of climatic environments and many large river catchments. Here we use the cicadas of the Platypleura plumosa complex to highlight the importance of catchments and their associated watersheds in driving diversification of terrestrial invertebrates that lack an aquatic life-stage. Population structure was found to correspond to primary and in some cases secondary catchments; highlighting the need to include information on catchment structure when formulating hypotheses of population diversification. Recognizing that climate change in the near future is likely to alter the environment, and particularly precipitation patterns, insight into recent patterns of population change related to catchments may be useful in a conservation context.
- Full Text:
- Date Issued: 2010
- Authors: Price, Benjamin W , Barker, Nigel P , Villet, Martin H
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441711 , vital:73909 , https://doi.org/10.1016/j.ympev.2009.10.011
- Description: Historical biogeography studies have at their disposal a small suite of vicariance models to explain genetic differentiation within and between species. One of these processes involves the role of river catchments and their associated watersheds, in driving diversification and is applicable to both aquatic and terrestrial organisms. Although the idea of catchments structuring the genetic history of aquatic organisms is reasonably well understood, their effect on terrestrial organisms has largely been overlooked, with relevant studies being limited in scope. South Africa presents a perfect test-bed for elucidating this mechanism of diversification due to its rich biodiversity, range of climatic environments and many large river catchments. Here we use the cicadas of the Platypleura plumosa complex to highlight the importance of catchments and their associated watersheds in driving diversification of terrestrial invertebrates that lack an aquatic life-stage. Population structure was found to correspond to primary and in some cases secondary catchments; highlighting the need to include information on catchment structure when formulating hypotheses of population diversification. Recognizing that climate change in the near future is likely to alter the environment, and particularly precipitation patterns, insight into recent patterns of population change related to catchments may be useful in a conservation context.
- Full Text:
- Date Issued: 2010
A “place in which to cry”: the place for race and a home for shame in Zoë Wicomb's Playing in the Light
- Authors: Dass, Minesh
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142588 , vital:38093 , DOI: 10.1080/1013929X.2011.602910
- Description: In Zoë Wicomb's Playing in the Light, the main character's troubled sense of identity (brought about by her parents' shameful decision to ‘play white’) is viscerally symbolised by her discomfort in her own and others' homes. In her Cape Town apartment she has nightmares about other houses. Her visits to her family home, where her elderly father lives alone, are similarly burdened by presences and memories she finds unwelcoming. And, her extended vacation to the UK, once she has discovered her family's secret, is a choice of “a place in which to cry” (Wicomb 2006: 191).
- Full Text:
- Date Issued: 2011
- Authors: Dass, Minesh
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142588 , vital:38093 , DOI: 10.1080/1013929X.2011.602910
- Description: In Zoë Wicomb's Playing in the Light, the main character's troubled sense of identity (brought about by her parents' shameful decision to ‘play white’) is viscerally symbolised by her discomfort in her own and others' homes. In her Cape Town apartment she has nightmares about other houses. Her visits to her family home, where her elderly father lives alone, are similarly burdened by presences and memories she finds unwelcoming. And, her extended vacation to the UK, once she has discovered her family's secret, is a choice of “a place in which to cry” (Wicomb 2006: 191).
- Full Text:
- Date Issued: 2011
Academic Practices and Reasoning: APR 111
- Authors: Scott, R , Blatchford, M
- Date: 2010-05
- Language: English
- Type: Examination paper
- Identifier: vital:18268 , http://hdl.handle.net/10353/d1011264
- Description: Academic Practices and Reasoning: APR 111, examination May/June 2010.
- Full Text: false
- Date Issued: 2010-05
- Authors: Scott, R , Blatchford, M
- Date: 2010-05
- Language: English
- Type: Examination paper
- Identifier: vital:18268 , http://hdl.handle.net/10353/d1011264
- Description: Academic Practices and Reasoning: APR 111, examination May/June 2010.
- Full Text: false
- Date Issued: 2010-05
Acanthurus tristis, a valid Indian Ocean surgeonfish (Perciformes: Acanthuridae)
- Randall, John E, 1924-, J.L.B. Smith Institute of Ichthyology
- Authors: Randall, John E, 1924- , J.L.B. Smith Institute of Ichthyology
- Date: 1993-01
- Subjects: Surgeonfishes , Fishes -- South Africa
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70933 , vital:29762 , 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. 54 , After examination of Col. Tickell’s unpublished manuscript and colour paintings of Burmese fishes, Day (1888) listed the surgeonfish Acanthurus tristis Tickell as a synonym of A. tennentii Gunther (1861); he gave the dorsal-fin spine count of 8 and provided a colour description, including mention of a white margin on the caudal fin. Of the species of Acanthurus, only A. pyroferus Kittlitz from the Pacific has 8 dorsal spines. Randall (1956a) treated tristis as a synonym of this pecies; the differences in colouration between tristis and pyroferus were regarded as within the range of variability of the latter. Both forms were observed together in Bali in 1982-1991. A. tristis is therefore regarded as a valid species and is redescribed. In the interest of stability of nomenclature, a neotype for A. tristis is designated.
- Full Text:
- Date Issued: 1993-01
- Authors: Randall, John E, 1924- , J.L.B. Smith Institute of Ichthyology
- Date: 1993-01
- Subjects: Surgeonfishes , Fishes -- South Africa
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/70933 , vital:29762 , 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. 54 , After examination of Col. Tickell’s unpublished manuscript and colour paintings of Burmese fishes, Day (1888) listed the surgeonfish Acanthurus tristis Tickell as a synonym of A. tennentii Gunther (1861); he gave the dorsal-fin spine count of 8 and provided a colour description, including mention of a white margin on the caudal fin. Of the species of Acanthurus, only A. pyroferus Kittlitz from the Pacific has 8 dorsal spines. Randall (1956a) treated tristis as a synonym of this pecies; the differences in colouration between tristis and pyroferus were regarded as within the range of variability of the latter. Both forms were observed together in Bali in 1982-1991. A. tristis is therefore regarded as a valid species and is redescribed. In the interest of stability of nomenclature, a neotype for A. tristis is designated.
- Full Text:
- Date Issued: 1993-01
Accelerated sludge solubilisation under sulphate reducing conditions: the effect of hydrolytic enzymes on sludge floc size distribution and EPS composition
- Akhurst, P, Rose, Peter D, Whiteley, Chris G, Pletschke, Brett I
- Authors: Akhurst, P , Rose, Peter D , Whiteley, Chris G , Pletschke, Brett I
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6455 , http://hdl.handle.net/10962/d1010430
- Description: Extracellular polymeric substances (EPS) are the construction materials for microbial aggregates such as biofilms, flocs and sludge, and greatly contribute to the structural integrity of sludge flocs in wastewater treatment processes. The loss of integrity of the sewage sludge floc is believed to be due to enhanced hydrolysis of important structural components such as lignin, protein and cellulose in the sludge floc matrix. The mechanism of enhanced sludge floc fracture, due to the action of enzymes hydrolysing these structural components, remains a key element in our understanding of how the floc integrity in systems utilising a sulphate reducing system is compromised. A range of relatively non-specific exogenous enzymes (ß-glucosidase, cellulase, proteases: trypsin, pronase E and chymotrypsin) were added to a sulphidogenic bioreactor- (containing both sulphate reducing bacteria (SRB) and a methanogenic bacterial system) and a (control) methanogenic bioreactor sample, and the effect of these enzymes on sludge floc size (diameter) distribution and EPS composition was investigated. Sludge samples from the bioreactors were examined under bright field and differential interference contrast light microscopy. Proteolytic and glucohydrolytic activity of the enzymes were monitored using standard enzyme assaying techniques, and Bradford, Somogyi-Nelson, and total carbohydrate assays were performed to establish the composition of the EPS (after extraction with 3% (v/v) glutaraldehyde and Sephacryl S-400 size exclusion chromatography). Sludge flocs present in the sulphidogenic environment of the sulphidogenic bioreactor were found to have smaller diameters than their counterparts present in the methanogenic bioreactor. The addition of hydrolytic (i.e. proteolytic and glycohydrolytic) enzymes resulted in an increased rate of matrix hydrolysis, leading to increased rates of floc fracture and deflocculation. The presence of ß-glucosidase, cellulase, and proteases naturally residing within the sludge floc was confirmed. We propose that the addition of commercially available enzymes may be prohibitively costly on a large scale, and that the activity of the enzymes naturally residing within the floc matrix be optimised or enhanced. As the bulk of the EPS was shown to be composed of mainly polysaccharides, we propose that by increasing the activity of the naturally occurring ß-glucosidases residing within the floc matrix, the process of deflocculation may be enhanced. As sulphide has been shown to increase the activity of this very important key enzyme, we propose that this is one of the contributing factors why sludge solubilisation is accelerated under sulphate reducing conditions.
- Full Text:
- Date Issued: 2002
- Authors: Akhurst, P , Rose, Peter D , Whiteley, Chris G , Pletschke, Brett I
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6455 , http://hdl.handle.net/10962/d1010430
- Description: Extracellular polymeric substances (EPS) are the construction materials for microbial aggregates such as biofilms, flocs and sludge, and greatly contribute to the structural integrity of sludge flocs in wastewater treatment processes. The loss of integrity of the sewage sludge floc is believed to be due to enhanced hydrolysis of important structural components such as lignin, protein and cellulose in the sludge floc matrix. The mechanism of enhanced sludge floc fracture, due to the action of enzymes hydrolysing these structural components, remains a key element in our understanding of how the floc integrity in systems utilising a sulphate reducing system is compromised. A range of relatively non-specific exogenous enzymes (ß-glucosidase, cellulase, proteases: trypsin, pronase E and chymotrypsin) were added to a sulphidogenic bioreactor- (containing both sulphate reducing bacteria (SRB) and a methanogenic bacterial system) and a (control) methanogenic bioreactor sample, and the effect of these enzymes on sludge floc size (diameter) distribution and EPS composition was investigated. Sludge samples from the bioreactors were examined under bright field and differential interference contrast light microscopy. Proteolytic and glucohydrolytic activity of the enzymes were monitored using standard enzyme assaying techniques, and Bradford, Somogyi-Nelson, and total carbohydrate assays were performed to establish the composition of the EPS (after extraction with 3% (v/v) glutaraldehyde and Sephacryl S-400 size exclusion chromatography). Sludge flocs present in the sulphidogenic environment of the sulphidogenic bioreactor were found to have smaller diameters than their counterparts present in the methanogenic bioreactor. The addition of hydrolytic (i.e. proteolytic and glycohydrolytic) enzymes resulted in an increased rate of matrix hydrolysis, leading to increased rates of floc fracture and deflocculation. The presence of ß-glucosidase, cellulase, and proteases naturally residing within the sludge floc was confirmed. We propose that the addition of commercially available enzymes may be prohibitively costly on a large scale, and that the activity of the enzymes naturally residing within the floc matrix be optimised or enhanced. As the bulk of the EPS was shown to be composed of mainly polysaccharides, we propose that by increasing the activity of the naturally occurring ß-glucosidases residing within the floc matrix, the process of deflocculation may be enhanced. As sulphide has been shown to increase the activity of this very important key enzyme, we propose that this is one of the contributing factors why sludge solubilisation is accelerated under sulphate reducing conditions.
- Full Text:
- Date Issued: 2002