A Crown on the Move: stylistic integration of the Luba-Lunda complex in Lunda-Kazembe performance
- Authors: Simbao, Ruth K
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147524 , vital:38646 , https://doi.org/10.1162/afar.2006.39.3.26
- Description: Carried on a scarlet and zebra-hide litter above the heads of a throbbing crowd, Mwata Kazembe XIX gloriously stretches out his arms as if to embrace a world that is his own (Fig. 1). As he parts the sea of well-wishers, splashes of red burst into view and the talking drum beats out its decree. Basking in a charged clamor where the senses blur in clouds of dust, Mwata gracefully sways from side to side, jangling the beads and cowries on the back of his akatasa crown. It is on this day that the Lunda-Kazembe Crown moves.
- Full Text:
- Authors: Simbao, Ruth K
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147524 , vital:38646 , https://doi.org/10.1162/afar.2006.39.3.26
- Description: Carried on a scarlet and zebra-hide litter above the heads of a throbbing crowd, Mwata Kazembe XIX gloriously stretches out his arms as if to embrace a world that is his own (Fig. 1). As he parts the sea of well-wishers, splashes of red burst into view and the talking drum beats out its decree. Basking in a charged clamor where the senses blur in clouds of dust, Mwata gracefully sways from side to side, jangling the beads and cowries on the back of his akatasa crown. It is on this day that the Lunda-Kazembe Crown moves.
- Full Text:
Versions of hospitality in recent writing on the fiction of JM Coetzee:
- Authors: Marais, Mike
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144039 , vital:38305 , DOI: 10.4314/eia.v40i1.8
- Description: In one of the interviews in Summertime, Martin, a former colleague, claims that he and the deceased John Coetzee felt their "presence" in South Africa "was legal but illegitimate," that it "was grounded in a crime, namely colonial conquest," which rendered them "sojourners, temporary residents, and to that extent without a home, without a homeland" (209-10). With this statement in mind, Maria J. Lopez argues that a sense of unbelonging underlies J. M. Coetzee's entire oeuvre, including the Australian fiction, and forms a kind of "imaginative and intellectual masterplot" (xii). ). It is this "narrative" that she traces in her monograph, starting with the early fiction and concluding with chapters on the fictionalised autobiographies and Australian fiction.
- Full Text:
- Authors: Marais, Mike
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144039 , vital:38305 , DOI: 10.4314/eia.v40i1.8
- Description: In one of the interviews in Summertime, Martin, a former colleague, claims that he and the deceased John Coetzee felt their "presence" in South Africa "was legal but illegitimate," that it "was grounded in a crime, namely colonial conquest," which rendered them "sojourners, temporary residents, and to that extent without a home, without a homeland" (209-10). With this statement in mind, Maria J. Lopez argues that a sense of unbelonging underlies J. M. Coetzee's entire oeuvre, including the Australian fiction, and forms a kind of "imaginative and intellectual masterplot" (xii). ). It is this "narrative" that she traces in her monograph, starting with the early fiction and concluding with chapters on the fictionalised autobiographies and Australian fiction.
- Full Text:
Responsive integrative treatment of PTSD and trauma related disorders : an expanded evidence-based model
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6223 , http://hdl.handle.net/10962/d1007679
- Description: In this article a practitioner oriented review of the literature on the treatment of post-traumatic stress disorder is used to construct a phase-based model that can serve as a basis for case formulation and treatment planning. Treatments shown to be efficacious in randomized controlled trials are listed and two discourses about them are contrasted. One calls for therapists to implement treatments scrupulously according to the manual, the other calls for flexibility and responsiveness to contextual understanding of the situation and personality of individual clients. Evidence for the centrality of the principles of this latter discourse for professional practice is summarized from work on case formulation, standards for therapist competence, and the concept of evidence-based practice. This provides the foundation for a model for treatment of PTSD, both simple and complex, that has five levels which represent increasing degrees of depth of clinical work. In accordance with the phased approach, conditions at one level need to be satisfied before proceeding to work on a deeper level. At each level specific areas of clinical focus are highlighted including risk management (at level 1), building the therapeutic alliance (at level 2) and trauma-focused work (at level 3). The model serves as a broad structured summary of accumulated clinical knowledge about PTSD and its treatment that provides an evidence-based foundation for assessment and treatment planning.
- Full Text:
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6223 , http://hdl.handle.net/10962/d1007679
- Description: In this article a practitioner oriented review of the literature on the treatment of post-traumatic stress disorder is used to construct a phase-based model that can serve as a basis for case formulation and treatment planning. Treatments shown to be efficacious in randomized controlled trials are listed and two discourses about them are contrasted. One calls for therapists to implement treatments scrupulously according to the manual, the other calls for flexibility and responsiveness to contextual understanding of the situation and personality of individual clients. Evidence for the centrality of the principles of this latter discourse for professional practice is summarized from work on case formulation, standards for therapist competence, and the concept of evidence-based practice. This provides the foundation for a model for treatment of PTSD, both simple and complex, that has five levels which represent increasing degrees of depth of clinical work. In accordance with the phased approach, conditions at one level need to be satisfied before proceeding to work on a deeper level. At each level specific areas of clinical focus are highlighted including risk management (at level 1), building the therapeutic alliance (at level 2) and trauma-focused work (at level 3). The model serves as a broad structured summary of accumulated clinical knowledge about PTSD and its treatment that provides an evidence-based foundation for assessment and treatment planning.
- Full Text:
Updating the ionospheric propagation factor, M(3000)F2, global model using the neural network technique and relevant geophysical input parameters
- Oronsaye, Samuel Iyen Jeffrey
- Authors: Oronsaye, Samuel Iyen Jeffrey
- Date: 2013
- Subjects: Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5434 , http://hdl.handle.net/10962/d1001609 , Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Description: This thesis presents an update to the ionospheric propagation factor, M(3000)F2, global empirical model developed by Oyeyemi et al. (2007) (NNO). An additional aim of this research was to produce the updated model in a form that could be used within the International Reference Ionosphere (IRI) global model without adding to the complexity of the IRI. M(3000)F2 is the highest frequency at which a radio signal can be received over a distance of 3000 km after reflection in the ionosphere. The study employed the artificial neural network (ANN) technique using relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. Ionosonde data from 135 ionospheric stations globally, including a number of equatorial stations, were available for this work. M(3000)F2 hourly values from 1976 to 2008, spanning all periods of low and high solar activity were used for model development and verification. A preliminary investigation was first carried out using a relatively small dataset to determine the appropriate input parameters for global M(3000)F2 parameter modelling. Inputs representing diurnal variation, seasonal variation, solar variation, modified dip latitude, longitude and latitude were found to be the optimum parameters for modelling the diurnal and seasonal variations of the M(3000)F2 parameter both on a temporal and spatial basis. The outcome of the preliminary study was applied to the overall dataset to develop a comprehensive ANN M(3000)F2 model which displays a remarkable improvement over the NNO model as well as the IRI version. The model shows 7.11% and 3.85% improvement over the NNO model as well as 13.04% and 10.05% over the IRI M(3000)F2 model, around high and low solar activity periods respectively. A comparison of the diurnal structure of the ANN and the IRI predicted values reveal that the ANN model is more effective in representing the diurnal structure of the M(3000)F2 values than the IRI M(3000)F2 model. The capability of the ANN model in reproducing the seasonal variation pattern of the M(3000)F2 values at 00h00UT, 06h00UT, 12h00UT, and l8h00UT more appropriately than the IRI version is illustrated in this work. A significant result obtained in this study is the ability of the ANN model in improving the post-sunset predicted values of the M(3000)F2 parameter which is known to be problematic to the IRI M(3000)F2 model in the low-latitude and the equatorial regions. The final M(3000)F2 model provides for an improved equatorial prediction and a simplified input space that allows for easy incorporation into the IRI model.
- Full Text:
- Authors: Oronsaye, Samuel Iyen Jeffrey
- Date: 2013
- Subjects: Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5434 , http://hdl.handle.net/10962/d1001609 , Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Description: This thesis presents an update to the ionospheric propagation factor, M(3000)F2, global empirical model developed by Oyeyemi et al. (2007) (NNO). An additional aim of this research was to produce the updated model in a form that could be used within the International Reference Ionosphere (IRI) global model without adding to the complexity of the IRI. M(3000)F2 is the highest frequency at which a radio signal can be received over a distance of 3000 km after reflection in the ionosphere. The study employed the artificial neural network (ANN) technique using relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. Ionosonde data from 135 ionospheric stations globally, including a number of equatorial stations, were available for this work. M(3000)F2 hourly values from 1976 to 2008, spanning all periods of low and high solar activity were used for model development and verification. A preliminary investigation was first carried out using a relatively small dataset to determine the appropriate input parameters for global M(3000)F2 parameter modelling. Inputs representing diurnal variation, seasonal variation, solar variation, modified dip latitude, longitude and latitude were found to be the optimum parameters for modelling the diurnal and seasonal variations of the M(3000)F2 parameter both on a temporal and spatial basis. The outcome of the preliminary study was applied to the overall dataset to develop a comprehensive ANN M(3000)F2 model which displays a remarkable improvement over the NNO model as well as the IRI version. The model shows 7.11% and 3.85% improvement over the NNO model as well as 13.04% and 10.05% over the IRI M(3000)F2 model, around high and low solar activity periods respectively. A comparison of the diurnal structure of the ANN and the IRI predicted values reveal that the ANN model is more effective in representing the diurnal structure of the M(3000)F2 values than the IRI M(3000)F2 model. The capability of the ANN model in reproducing the seasonal variation pattern of the M(3000)F2 values at 00h00UT, 06h00UT, 12h00UT, and l8h00UT more appropriately than the IRI version is illustrated in this work. A significant result obtained in this study is the ability of the ANN model in improving the post-sunset predicted values of the M(3000)F2 parameter which is known to be problematic to the IRI M(3000)F2 model in the low-latitude and the equatorial regions. The final M(3000)F2 model provides for an improved equatorial prediction and a simplified input space that allows for easy incorporation into the IRI model.
- Full Text:
A teaching case study of the strategic alignment of business strategy and information technology strategy at Nedbank
- Authors: Tsoaeli, Tebalo
- Date: 2013
- Subjects: Nedbank Banks and banking -- South Africa Business planning Information technology
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:720 , http://hdl.handle.net/10962/d1001883
- Description: In today’s business world, a lot of organizations are investing heavily in Information Technology (IT) in order to develop a competitive edge. According to Loukis, Sapounas and Milionis (2009:85) “firms all over the world make significant investments in IT aiming to increase their efficiency and effectiveness”. According to Cline and Guynes (2001:10), “during the last 30 years, IT has become an increasingly integral part of business operations”. Most of the times, organizations fail to get real value from the investments made in IT. This is mainly due to the fact that organizations fail to realize the value brought about by aligning IT strategy with Business strategy. Hu and Huang (2004:60) state that “each year organizations invest in IT to improve their competitive advantage and ultimately their business performance; however, more often than not, the anticipated benefits of IT investments fail to materialize due to misalignment of or lack of alignment, between the business and IT strategies”. Henderson and Venkatraman (1999:475) emphasize that “alignment is a desired state for organizations investing in IT that is not always achieved, as it often entails a radical change in the way managers consider IT”. It is through the alignment of IT strategy and Business strategy that organizations are able to realize the value brought about by investing in IT. Papp (2001:20)illustrates that “misalignment can cause problems with not only the development and integration of business and IT strategies, but can actually prevent IT from being fully leveraged to its maximum potential within an organization”. An organization that realizes the value of aligning IT strategy and Business strategy is able to develop a competitive advantage over its competitors. According to Daneshvar and Ramesh (2010:1) “each organization is aware of the special effects, benefits and implication of IT in business performance and also its capacity in building sustainable competitive advantages”.
- Full Text:
- Authors: Tsoaeli, Tebalo
- Date: 2013
- Subjects: Nedbank Banks and banking -- South Africa Business planning Information technology
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:720 , http://hdl.handle.net/10962/d1001883
- Description: In today’s business world, a lot of organizations are investing heavily in Information Technology (IT) in order to develop a competitive edge. According to Loukis, Sapounas and Milionis (2009:85) “firms all over the world make significant investments in IT aiming to increase their efficiency and effectiveness”. According to Cline and Guynes (2001:10), “during the last 30 years, IT has become an increasingly integral part of business operations”. Most of the times, organizations fail to get real value from the investments made in IT. This is mainly due to the fact that organizations fail to realize the value brought about by aligning IT strategy with Business strategy. Hu and Huang (2004:60) state that “each year organizations invest in IT to improve their competitive advantage and ultimately their business performance; however, more often than not, the anticipated benefits of IT investments fail to materialize due to misalignment of or lack of alignment, between the business and IT strategies”. Henderson and Venkatraman (1999:475) emphasize that “alignment is a desired state for organizations investing in IT that is not always achieved, as it often entails a radical change in the way managers consider IT”. It is through the alignment of IT strategy and Business strategy that organizations are able to realize the value brought about by investing in IT. Papp (2001:20)illustrates that “misalignment can cause problems with not only the development and integration of business and IT strategies, but can actually prevent IT from being fully leveraged to its maximum potential within an organization”. An organization that realizes the value of aligning IT strategy and Business strategy is able to develop a competitive advantage over its competitors. According to Daneshvar and Ramesh (2010:1) “each organization is aware of the special effects, benefits and implication of IT in business performance and also its capacity in building sustainable competitive advantages”.
- Full Text:
Section 40 of the Consumer Protection Act in comparative perspective: aantekeninge
- Authors: Glover, Graham B
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70527 , vital:29672 , https://hdl.handle.net/10520/EJC144971
- Description: The purpose of this comment is to consider some of the problems with how we are to understand the role and purpose of section 40 of South Africa's Consumer Protection Act 68 of 2008 when viewed from a doctrinal perspective. Section 40 has the heading "Unconscionable conduct", and contains three subsections.
- Full Text: false
- Authors: Glover, Graham B
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70527 , vital:29672 , https://hdl.handle.net/10520/EJC144971
- Description: The purpose of this comment is to consider some of the problems with how we are to understand the role and purpose of section 40 of South Africa's Consumer Protection Act 68 of 2008 when viewed from a doctrinal perspective. Section 40 has the heading "Unconscionable conduct", and contains three subsections.
- Full Text: false
Zinc (II) 2, 9, 16, 23-tetrakis [4-(N-methylpyridyloxy)]-phthalocyanine anchored on an electrospun polysulfone polymer fiber: Application for photosensitized conversion of methyl orange
- Zugle, Ruphino, Nyokong, Tebello
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232741 , vital:50020 , xlink:href="https://doi.org/10.1016/j.molcata.2012.10.001"
- Description: In this work, a comparative study of photodegradation of methyl orange, an azo dye, in homogeneous aqueous solution of a quarternized cationic zinc phthalocyanine and a heterogeneous catalytic system based on the same phthalocyanine anchored on polysulfone polymer fiber is presented. In both cases, conversion involved the azo bond of the dye with no detectable opening up of the aromatic benzene rings. The reaction kinetics in both cases were consistent with first order with the conversion occurring in the homogeneous system being faster than when the functionalized polymer fiber was used. The reaction products consisted of a coupling product as well as a series of oligopolymeric products.
- Full Text:
- Authors: Zugle, Ruphino , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232741 , vital:50020 , xlink:href="https://doi.org/10.1016/j.molcata.2012.10.001"
- Description: In this work, a comparative study of photodegradation of methyl orange, an azo dye, in homogeneous aqueous solution of a quarternized cationic zinc phthalocyanine and a heterogeneous catalytic system based on the same phthalocyanine anchored on polysulfone polymer fiber is presented. In both cases, conversion involved the azo bond of the dye with no detectable opening up of the aromatic benzene rings. The reaction kinetics in both cases were consistent with first order with the conversion occurring in the homogeneous system being faster than when the functionalized polymer fiber was used. The reaction products consisted of a coupling product as well as a series of oligopolymeric products.
- Full Text:
From panic disorder to complex traumatic stress disorder : retrospective reflections on the case of Tariq
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6234 , http://hdl.handle.net/10962/d1007784
- Description: This is a phenomenological-hermeneutic case study of Tariq who initially presented with panic disorder. It documents how, as therapy proceeded, the underlying meaning of his initial panic deepened as its roots in traumatic memories of childhood emerged. There were four spaced phases of treatment over four years. The first focused on anxiety management; the second was conceptualized within schema-focused therapy, and evoked and worked with childhood memories using inner child guided imagery; in the third and fourth phases insights gained led to an authentic re-engagement with family members in relationships that had been problematic. The panic attacks resolved and there were two dreams representing a reconfiguring of his relationship with his deceased father. The first two phases were the focus of an unpublished case study presented at a conference in 1995. This article incorporates material from that study and looks back at the case both in light of developments in phases two and three and also in light of theoretical developments in our understanding of complex trauma since the initial presentation.
- Full Text:
- Authors: Edwards, David J A
- Date: 2013
- Language: English
- Type: Article
- Identifier: vital:6234 , http://hdl.handle.net/10962/d1007784
- Description: This is a phenomenological-hermeneutic case study of Tariq who initially presented with panic disorder. It documents how, as therapy proceeded, the underlying meaning of his initial panic deepened as its roots in traumatic memories of childhood emerged. There were four spaced phases of treatment over four years. The first focused on anxiety management; the second was conceptualized within schema-focused therapy, and evoked and worked with childhood memories using inner child guided imagery; in the third and fourth phases insights gained led to an authentic re-engagement with family members in relationships that had been problematic. The panic attacks resolved and there were two dreams representing a reconfiguring of his relationship with his deceased father. The first two phases were the focus of an unpublished case study presented at a conference in 1995. This article incorporates material from that study and looks back at the case both in light of developments in phases two and three and also in light of theoretical developments in our understanding of complex trauma since the initial presentation.
- Full Text:
Understanding livelihood strategies of urban women traders : a case of Magaba, Harare in Zimbabwe
- Authors: Chirau, Takunda John
- Date: 2013
- Subjects: Street vendors -- Zimbabwe -- Harare Women -- Zimbabwe -- Harare -- Social conditions Women -- Zimbabwe -- Harare -- Economic conditions Urban poor -- Zimbabwe -- Harare
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3335 , http://hdl.handle.net/10962/d1003742
- Description: This thesis seeks to understand and analyze the livelihood strategies of urban women traders at Magaba in Harare (Zimbabwe) in the context of the contemporary economic and political crisis. The crisis emerged in the 1990s with the introduction of a structural adjustment programme and deepened further with the fast track land reform programme initiated by the Zimbabwean government in the year 2000. The crisis has involved a down-sizing of the Zimbabwean economy and a massive rise in the rate of unemployment in the formal economy. Consequently urban life became increasingly unbearable for poor blacks and informal economic activities blossomed and started to make a significant contribution to household income and livelihoods. The role of women in the informal economy was particularly pronounced. Theoretically, the thesis is underpinned by the sustainable livelihoods framework. In examining the vulnerability context of the Magaba women traders and the institutional interventions which complicate the lives and livelihoods of these traders, I identify and unpack their diverse livelihood activities and strategies and the resources (or assets) they deploy in constructing urban livelihoods. Though their livelihood portfolios complement any earnings from formal employment by household members and though they contribute to their household’s sustenance, there are a number of daily challenges which they face in their trading activities and which they seek to counteract through a range of often ingenious coping mechanisms. The thesis is important for a number of reasons. It fills an important empirical gap in the study of Magaba market specifically, it brings to the fore the gendered character of the informal trading activities in urban Zimbabwe, and it deploys the livelihoods framework in a manner which is sensitive to both structure and agency.
- Full Text:
- Authors: Chirau, Takunda John
- Date: 2013
- Subjects: Street vendors -- Zimbabwe -- Harare Women -- Zimbabwe -- Harare -- Social conditions Women -- Zimbabwe -- Harare -- Economic conditions Urban poor -- Zimbabwe -- Harare
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3335 , http://hdl.handle.net/10962/d1003742
- Description: This thesis seeks to understand and analyze the livelihood strategies of urban women traders at Magaba in Harare (Zimbabwe) in the context of the contemporary economic and political crisis. The crisis emerged in the 1990s with the introduction of a structural adjustment programme and deepened further with the fast track land reform programme initiated by the Zimbabwean government in the year 2000. The crisis has involved a down-sizing of the Zimbabwean economy and a massive rise in the rate of unemployment in the formal economy. Consequently urban life became increasingly unbearable for poor blacks and informal economic activities blossomed and started to make a significant contribution to household income and livelihoods. The role of women in the informal economy was particularly pronounced. Theoretically, the thesis is underpinned by the sustainable livelihoods framework. In examining the vulnerability context of the Magaba women traders and the institutional interventions which complicate the lives and livelihoods of these traders, I identify and unpack their diverse livelihood activities and strategies and the resources (or assets) they deploy in constructing urban livelihoods. Though their livelihood portfolios complement any earnings from formal employment by household members and though they contribute to their household’s sustenance, there are a number of daily challenges which they face in their trading activities and which they seek to counteract through a range of often ingenious coping mechanisms. The thesis is important for a number of reasons. It fills an important empirical gap in the study of Magaba market specifically, it brings to the fore the gendered character of the informal trading activities in urban Zimbabwe, and it deploys the livelihoods framework in a manner which is sensitive to both structure and agency.
- Full Text:
Surface patterning using scanning electrochemical microscopy to locally trigger a “click” chemistry reaction
- Quinton, Damien, Maringa, Audacity, Griveau, Sophie, Nyokong, Tebello, Bedioui, Fethi
- Authors: Quinton, Damien , Maringa, Audacity , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
- Language: English
- Type: Article
- Identifier: vital:7331 , http://hdl.handle.net/10962/d1020592
- Description: We report on the surface micropatterning of conductive surfaces via the electrochemical triggering of a click reaction, the copper(I) catalyzed azide–alkyne cycloaddition reaction (CuAAC) by SECM via a two-step approach: (i) functionalization on the entire surface with azido-aryl groups by using the diazonium approach followed by (ii) the covalent linkage of alkyne-bearing ferrocene by CuAAC within a local area by SECM. More precisely, the click reaction was triggered by Cu(I) catalyst generation for 30 min at the SECM tip positioned ≈ 10 μm above the azido-aryl modified surface. The dimension of the spot obtained under these conditions was ≈ 75 μm. The electrochemical imaging by SECM of the ultra thin area locally clicked with ferrocene moieties was made thanks to the electrocatalytic properties of the ferrocene modified surface towards ferrocyanide electrooxidation. This local clicking procedure opens the gate to further controlled functionalization of restricted small substrates. , Original publication is available at http://dx.doi.org/10.1016/j.elecom.2013.03.021
- Full Text: false
- Authors: Quinton, Damien , Maringa, Audacity , Griveau, Sophie , Nyokong, Tebello , Bedioui, Fethi
- Language: English
- Type: Article
- Identifier: vital:7331 , http://hdl.handle.net/10962/d1020592
- Description: We report on the surface micropatterning of conductive surfaces via the electrochemical triggering of a click reaction, the copper(I) catalyzed azide–alkyne cycloaddition reaction (CuAAC) by SECM via a two-step approach: (i) functionalization on the entire surface with azido-aryl groups by using the diazonium approach followed by (ii) the covalent linkage of alkyne-bearing ferrocene by CuAAC within a local area by SECM. More precisely, the click reaction was triggered by Cu(I) catalyst generation for 30 min at the SECM tip positioned ≈ 10 μm above the azido-aryl modified surface. The dimension of the spot obtained under these conditions was ≈ 75 μm. The electrochemical imaging by SECM of the ultra thin area locally clicked with ferrocene moieties was made thanks to the electrocatalytic properties of the ferrocene modified surface towards ferrocyanide electrooxidation. This local clicking procedure opens the gate to further controlled functionalization of restricted small substrates. , Original publication is available at http://dx.doi.org/10.1016/j.elecom.2013.03.021
- Full Text: false
An investigation into control mechanisms of driving performance : resource depletion and effort-regulation
- Authors: Louw, Tyron Linton
- Date: 2013
- Subjects: Automobile driving simulators , Automobile driving -- Psychological aspects , Automobile driving -- Physiological aspects , Traffic accidents , Traffic safety , Fatigue
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5101 , http://hdl.handle.net/10962/d1001842 , Automobile driving simulators , Automobile driving -- Psychological aspects , Automobile driving -- Physiological aspects , Traffic accidents , Traffic safety , Fatigue
- Description: Driver fatigue is a complex phenomenon that has a range of causal factors including sleeprelated and task-related factors. These manifest as different safety and performance outcomes. Extensive research has been applied to linking these factors to performance impairment. However, little research focuses on the mechanisms by which this link exists. This research project therefore focuses on the processes underlying how driving performance is controlled and maintained during the development on non-sleep-related driver fatigue. The main aim was to establish whether progressive impairment of driving control over a prolonged drive could be attributed to a depletion of attentional resources, as proposed by Resource Theory, or to a withdrawal of effort, as proposed by Effort-Regulation Theory. As a multicomponent skill, driving requires perception, cognition and motor output. The secondary aim of this research was therefore to assess whether a prolonged drive impairs stage-specific information processing. Participants (n=24) in three experimental groups performed a 90-minute simulated drive wherein they were expected to keep the bonnet of a car on a lane (tracking task). The three groups differed in terms of lane width: small, medium and large, corresponding to low, medium, and high task-demand, respectively. To assess the impacts of this task on stagespecific information processing, participants performed a set of resource specific tests before and after the prolonged drive. Each task had two difficulty variations to ensure that performance decrement was due not only to the task-characteristic, but specifically to resource depletion. The tests probing information processing were: a modified Fitts' tapping task for motor programming, a digit recall task for perception, and an object recognition reading task for cognition. Performance was measured as lateral deviation of the car. Physiological measures included heart rate frequency (HR) and various time- and frequencydomain heart rate variability (HRV) parameters, eye blink frequency and duration. The Borg CR-10 scale was used to evaluate subjective effort and fatigue during the task. Driving control declined over time and was supplemented by HR, HRV, blink frequency and duration, indicating an increase in parasympathetic activity (or a reduction in arousal). An increase in blink frequency was considered as a sign of withdrawal of attentional resources over time. Driving control declined to a greater extent in the large road width group and reflected a lower parasympathetic activity, whereas the inverse was observed for the small road width group. Resource tests reveal a non-specific impairment of information processing following the prolonged drive. However, this was accompanied by an increase in parasympathetic activity. Overall, results indicate that Effort-Regulation Theory better accounts for the impairment of driving control in prolonged driving than does Resource Theory. This suggests that the impact of fatigue is guided more by task goals and intrinsic motivation than by the manner in which the fatigue state developed. Moreover, performance impairment by effort-regulation is dependant more on time on task than on task-demand
- Full Text:
- Authors: Louw, Tyron Linton
- Date: 2013
- Subjects: Automobile driving simulators , Automobile driving -- Psychological aspects , Automobile driving -- Physiological aspects , Traffic accidents , Traffic safety , Fatigue
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5101 , http://hdl.handle.net/10962/d1001842 , Automobile driving simulators , Automobile driving -- Psychological aspects , Automobile driving -- Physiological aspects , Traffic accidents , Traffic safety , Fatigue
- Description: Driver fatigue is a complex phenomenon that has a range of causal factors including sleeprelated and task-related factors. These manifest as different safety and performance outcomes. Extensive research has been applied to linking these factors to performance impairment. However, little research focuses on the mechanisms by which this link exists. This research project therefore focuses on the processes underlying how driving performance is controlled and maintained during the development on non-sleep-related driver fatigue. The main aim was to establish whether progressive impairment of driving control over a prolonged drive could be attributed to a depletion of attentional resources, as proposed by Resource Theory, or to a withdrawal of effort, as proposed by Effort-Regulation Theory. As a multicomponent skill, driving requires perception, cognition and motor output. The secondary aim of this research was therefore to assess whether a prolonged drive impairs stage-specific information processing. Participants (n=24) in three experimental groups performed a 90-minute simulated drive wherein they were expected to keep the bonnet of a car on a lane (tracking task). The three groups differed in terms of lane width: small, medium and large, corresponding to low, medium, and high task-demand, respectively. To assess the impacts of this task on stagespecific information processing, participants performed a set of resource specific tests before and after the prolonged drive. Each task had two difficulty variations to ensure that performance decrement was due not only to the task-characteristic, but specifically to resource depletion. The tests probing information processing were: a modified Fitts' tapping task for motor programming, a digit recall task for perception, and an object recognition reading task for cognition. Performance was measured as lateral deviation of the car. Physiological measures included heart rate frequency (HR) and various time- and frequencydomain heart rate variability (HRV) parameters, eye blink frequency and duration. The Borg CR-10 scale was used to evaluate subjective effort and fatigue during the task. Driving control declined over time and was supplemented by HR, HRV, blink frequency and duration, indicating an increase in parasympathetic activity (or a reduction in arousal). An increase in blink frequency was considered as a sign of withdrawal of attentional resources over time. Driving control declined to a greater extent in the large road width group and reflected a lower parasympathetic activity, whereas the inverse was observed for the small road width group. Resource tests reveal a non-specific impairment of information processing following the prolonged drive. However, this was accompanied by an increase in parasympathetic activity. Overall, results indicate that Effort-Regulation Theory better accounts for the impairment of driving control in prolonged driving than does Resource Theory. This suggests that the impact of fatigue is guided more by task goals and intrinsic motivation than by the manner in which the fatigue state developed. Moreover, performance impairment by effort-regulation is dependant more on time on task than on task-demand
- Full Text:
Creating a new declaration of rights : a critical reconstruction of earth jurisprudence's global legislative framework
- Authors: Lenferna, Georges Alexandre
- Date: 2013
- Subjects: Universal Declaration , Rights , Earth , Environment , Ethics , Environmental law, International -- Research , Environmental law, International -- Philosophy , Environmental ethics -- Research , Nature conservation -- Law and legislation -- Research , Jurisprudence -- Research , Law -- Philosophy
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2704 , http://hdl.handle.net/10962/d1001979
- Description: This thesis aims to critique the Universal Declaration of the Rights of Mother Earth and its underlying moral justification in order to provide a stronger and improved version of both. In Chapter 1 I explore what sort of moral justification is necessary to establish the Universal Declaration on firm grounds and explore its relation to environmental ethics and rights discourse. I argue that a non-anthropocentric perspective is necessary to justify the Universal Declaration’s rights. In Chapter 2 I explore the underlying justification of the Universal Declaration as discovered in the works of Cormac Cullinan and Father Thomas Berry. I argue that their ethical framework is indeterminate, has many ambiguities and uncertainties, and, among other problems, it does not provide a clear action-guiding framework. In Chapter 3 I develop an alternative justification for the Universal Declaration. I argue against many predominant moral theories, that in light of our best scientific and moral understanding we should expand the realm of moral concern to include all living beings, a moral theory I call Life’s Imperative. In Chapter 4 I illustrate that Life’s Imperative is a much stronger, more coherent justification for the Universal Declaration, one that coheres with both our best understanding of the natural world and our relation to it, and to an environmental ethic reflective of that relationship. Unfortunately many of the weaknesses in the current implicit justification of the Universal Declaration have also led to it enshrining rights that are themselves problematic. In order to address these issues, I revise its rights to accord with the stronger justification that I established in Chapter 3. The end result of doing so is a revised version of the Universal Declaration
- Full Text:
- Authors: Lenferna, Georges Alexandre
- Date: 2013
- Subjects: Universal Declaration , Rights , Earth , Environment , Ethics , Environmental law, International -- Research , Environmental law, International -- Philosophy , Environmental ethics -- Research , Nature conservation -- Law and legislation -- Research , Jurisprudence -- Research , Law -- Philosophy
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:2704 , http://hdl.handle.net/10962/d1001979
- Description: This thesis aims to critique the Universal Declaration of the Rights of Mother Earth and its underlying moral justification in order to provide a stronger and improved version of both. In Chapter 1 I explore what sort of moral justification is necessary to establish the Universal Declaration on firm grounds and explore its relation to environmental ethics and rights discourse. I argue that a non-anthropocentric perspective is necessary to justify the Universal Declaration’s rights. In Chapter 2 I explore the underlying justification of the Universal Declaration as discovered in the works of Cormac Cullinan and Father Thomas Berry. I argue that their ethical framework is indeterminate, has many ambiguities and uncertainties, and, among other problems, it does not provide a clear action-guiding framework. In Chapter 3 I develop an alternative justification for the Universal Declaration. I argue against many predominant moral theories, that in light of our best scientific and moral understanding we should expand the realm of moral concern to include all living beings, a moral theory I call Life’s Imperative. In Chapter 4 I illustrate that Life’s Imperative is a much stronger, more coherent justification for the Universal Declaration, one that coheres with both our best understanding of the natural world and our relation to it, and to an environmental ethic reflective of that relationship. Unfortunately many of the weaknesses in the current implicit justification of the Universal Declaration have also led to it enshrining rights that are themselves problematic. In order to address these issues, I revise its rights to accord with the stronger justification that I established in Chapter 3. The end result of doing so is a revised version of the Universal Declaration
- Full Text:
Environmental water quality management of glyphosate-based herbicides in South Africa
- Authors: Mensah, Paul Kojo
- Date: 2013
- Subjects: Water quality management -- South Africa Water quality management -- Environmental Aspects -- South Africa Herbicides -- Environmental aspects -- South Africa Herbicides -- Toxicology -- South Africa Water -- Glyphosate content -- South Africa Water -- Pollution -- South Africa Water quality -- Measurement -- South Africa Water -- Analysis -- South Africa Freshwater ecology -- South Africa Integrated water development -- South Africa Caridina -- Effect of pollution on -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6023 , http://hdl.handle.net/10962/d1001987
- Description: Although the use of pesticides is necessary to meet the socio-economic needs of many developing countries, especially in Africa, side effects of these bio-active chemicals have contributed to contaminating aquatic and terrestrial ecosystems. Environmental water quality degradation by pesticides interferes with ecosystem health and poses numerous risks to aquatic life. In South Africa, glyphosate-based herbicides are frequently used to control weeds and invading alien plants, but ultimately end up in freshwater ecosystems. However, there are no South African-based environmental water quality management strategies to regulate these bio-active chemicals. Therefore, this study sought to provide a sound scientific background for the environmental water quality management of glyphosate-based herbicides in South Africa, by conducting both laboratory and field investigations. In the laboratory investigations, aquatic ecotoxicological methods were used to evaluate responses of the freshwater aquatic shrimp Caridina nilotica exposed to Roundup® at different biological system scales, and the responses of multiple South African aquatic species exposed to Roundup® through species sensitivity distribution (SSD). In the field investigations, the effect of Kilo Max WSG on the physicochemical and biological conditions of three selected sites in the Swartkops River before and after a spray episode by Working for Water were evaluated through biomonitoring, using the South African Scoring System version 5 (SASS5) as a sampling protocol. Both Roundup® and Kilo Max WSG are glyphosate-based herbicides. All the data were subjected to relevant statistical analyses. Findings of this study revealed that Roundup® elicited responses at different biological system scales in C. nilotica, while SSD estimates were used to derive proposed water quality guidelines for glyphosate-based herbicides in South Africa. The biomonitoring revealed that using glyphosate-based herbicides to control water hyacinth within the Swartkops River had a negligible impact on the physicochemical and biological conditions. Based on these findings, a conceptual framework that can be used for the integrated environmental water quality management of glyphosate-based herbicides in South Africa was developed as part of integrated water resource management (IWRM). The combined data sets contribute to a sound scientific basis for the environmental water quality management of glyphosate-based herbicides in South Africa.
- Full Text:
- Authors: Mensah, Paul Kojo
- Date: 2013
- Subjects: Water quality management -- South Africa Water quality management -- Environmental Aspects -- South Africa Herbicides -- Environmental aspects -- South Africa Herbicides -- Toxicology -- South Africa Water -- Glyphosate content -- South Africa Water -- Pollution -- South Africa Water quality -- Measurement -- South Africa Water -- Analysis -- South Africa Freshwater ecology -- South Africa Integrated water development -- South Africa Caridina -- Effect of pollution on -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6023 , http://hdl.handle.net/10962/d1001987
- Description: Although the use of pesticides is necessary to meet the socio-economic needs of many developing countries, especially in Africa, side effects of these bio-active chemicals have contributed to contaminating aquatic and terrestrial ecosystems. Environmental water quality degradation by pesticides interferes with ecosystem health and poses numerous risks to aquatic life. In South Africa, glyphosate-based herbicides are frequently used to control weeds and invading alien plants, but ultimately end up in freshwater ecosystems. However, there are no South African-based environmental water quality management strategies to regulate these bio-active chemicals. Therefore, this study sought to provide a sound scientific background for the environmental water quality management of glyphosate-based herbicides in South Africa, by conducting both laboratory and field investigations. In the laboratory investigations, aquatic ecotoxicological methods were used to evaluate responses of the freshwater aquatic shrimp Caridina nilotica exposed to Roundup® at different biological system scales, and the responses of multiple South African aquatic species exposed to Roundup® through species sensitivity distribution (SSD). In the field investigations, the effect of Kilo Max WSG on the physicochemical and biological conditions of three selected sites in the Swartkops River before and after a spray episode by Working for Water were evaluated through biomonitoring, using the South African Scoring System version 5 (SASS5) as a sampling protocol. Both Roundup® and Kilo Max WSG are glyphosate-based herbicides. All the data were subjected to relevant statistical analyses. Findings of this study revealed that Roundup® elicited responses at different biological system scales in C. nilotica, while SSD estimates were used to derive proposed water quality guidelines for glyphosate-based herbicides in South Africa. The biomonitoring revealed that using glyphosate-based herbicides to control water hyacinth within the Swartkops River had a negligible impact on the physicochemical and biological conditions. Based on these findings, a conceptual framework that can be used for the integrated environmental water quality management of glyphosate-based herbicides in South Africa was developed as part of integrated water resource management (IWRM). The combined data sets contribute to a sound scientific basis for the environmental water quality management of glyphosate-based herbicides in South Africa.
- Full Text:
Afro-communitarianism and the nature of reconciliation
- Authors: Oelofsen, Rianna
- Date: 2013
- Subjects: Ubuntu (Philosophy) Reconciliation -- South Africa Communitarianism -- Africa Philosophy, African
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2736 , http://hdl.handle.net/10962/d1006809
- Description: In this dissertation I sketch a conception of personhood as understood from within an Afrocommunitarian worldview, and argue that this understanding of personhood has implications for understanding the concept of reconciliation. Understanding ‘being human’ as a collective, communal enterprise has implications for how responsibility, justice, forgiveness and humanization (all cognate concepts of reconciliation) are conceptualized. In line with this understanding of reconciliation and its cognate concepts, I argue that the humanization of self and other (according to the Afrocommunitarian understanding of personhood) is required for addressing the ‘inferiority’ and concurrent ‘superiority’ racial complexes as diagnosed by Franz Fanon and Steve Biko. These complexes reach deeply within individual and collective psyches and political identities, and I argue that political solutions to protracted conflict (in South Africa and other racially charged contexts) which do not address these deeply entrenched pathologies will be inadequate according to an Afrocommunitarian framework.
- Full Text:
- Authors: Oelofsen, Rianna
- Date: 2013
- Subjects: Ubuntu (Philosophy) Reconciliation -- South Africa Communitarianism -- Africa Philosophy, African
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2736 , http://hdl.handle.net/10962/d1006809
- Description: In this dissertation I sketch a conception of personhood as understood from within an Afrocommunitarian worldview, and argue that this understanding of personhood has implications for understanding the concept of reconciliation. Understanding ‘being human’ as a collective, communal enterprise has implications for how responsibility, justice, forgiveness and humanization (all cognate concepts of reconciliation) are conceptualized. In line with this understanding of reconciliation and its cognate concepts, I argue that the humanization of self and other (according to the Afrocommunitarian understanding of personhood) is required for addressing the ‘inferiority’ and concurrent ‘superiority’ racial complexes as diagnosed by Franz Fanon and Steve Biko. These complexes reach deeply within individual and collective psyches and political identities, and I argue that political solutions to protracted conflict (in South Africa and other racially charged contexts) which do not address these deeply entrenched pathologies will be inadequate according to an Afrocommunitarian framework.
- Full Text:
Form over function? The practical application of the Recognition of Customary Marriages Act 1998 in South Africa
- Authors: Kruuse, Helen
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54094 , vital:26389 , http://journals.co.za/content/ju_jur/2013/1/EJC148455
- Description: The Recognition of Customary Marriages Act 120 of 1998 is a major legislative measure for the development of customary marriages in line with the constitutional principle of equality, specifically for women. The article explores the interactions between this ideal in the Act with empirical observations and the latest judicial decisions concerning its application. It considers various examples of the lack of protection of women in relationships of a customary nature, and it concludes that both the state and courts favour a formal or definitional approach to customary marriage. In considering alternative approaches that could adequately protect vulnerable parties, two conclusions emerge: First, the article recommends a wholesale revision of the South African family law approach from a focus on form to dependency. Second (and as a short-term measure), the article advocates for the putative marriage doctrine to be applied in the customary marriage context to protect many women who are denied access to 'customary marriage' as a form, and as a result, all of the benefits that flow from such marriage.
- Full Text:
- Authors: Kruuse, Helen
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: http://hdl.handle.net/10962/54094 , vital:26389 , http://journals.co.za/content/ju_jur/2013/1/EJC148455
- Description: The Recognition of Customary Marriages Act 120 of 1998 is a major legislative measure for the development of customary marriages in line with the constitutional principle of equality, specifically for women. The article explores the interactions between this ideal in the Act with empirical observations and the latest judicial decisions concerning its application. It considers various examples of the lack of protection of women in relationships of a customary nature, and it concludes that both the state and courts favour a formal or definitional approach to customary marriage. In considering alternative approaches that could adequately protect vulnerable parties, two conclusions emerge: First, the article recommends a wholesale revision of the South African family law approach from a focus on form to dependency. Second (and as a short-term measure), the article advocates for the putative marriage doctrine to be applied in the customary marriage context to protect many women who are denied access to 'customary marriage' as a form, and as a result, all of the benefits that flow from such marriage.
- Full Text:
An exploration of strategies to enhance grade 8 learners' reading comprehension skills
- Authors: Matakane, Euphimia Nobuzwe
- Date: 2013
- Subjects: Reading (Secondary) -- Research Reading comprehension
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1834 , http://hdl.handle.net/10962/d1004330
- Description: This thesis reports on an Action Research case study into the teaching of comprehension strategies to Grade 8 learners in a rural high school in the Eastern Cape, South Africa. The learners in this study, who were studying English as an additional language, experienced difficulties in comprehending English text. A series of six lessons were designed to teach comprehension strategies to improve the learners' performance in reading comprehension. The purpose of the intervention was to equip the learners with skills that would enable them to improve their reading comprehension and evaluate their effectiveness as readers. The intervention was also intended to assess my teaching, which was challenged by the need to deal with learners' poor levels of reading comprehension. The data was collected using the following research techniques: interviews, questionnaires, non-participant observation, learners' and researcher's journals, document analysis The data analysis revealed that a lack of resources to learn English; limited English language due to lack of exposure; and learners' lack of foundational knowledge from their primary schools were barriers to the successful teaching of comprehension strategies. Despite such barriers, however, this research provides evidence that teaching comprehension strategies can be effective if it is taught systematically, and applied continuously. Personally, I learnt that I had to modify my methods of teaching due to the response of learners to the lessons taught.
- Full Text:
- Authors: Matakane, Euphimia Nobuzwe
- Date: 2013
- Subjects: Reading (Secondary) -- Research Reading comprehension
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1834 , http://hdl.handle.net/10962/d1004330
- Description: This thesis reports on an Action Research case study into the teaching of comprehension strategies to Grade 8 learners in a rural high school in the Eastern Cape, South Africa. The learners in this study, who were studying English as an additional language, experienced difficulties in comprehending English text. A series of six lessons were designed to teach comprehension strategies to improve the learners' performance in reading comprehension. The purpose of the intervention was to equip the learners with skills that would enable them to improve their reading comprehension and evaluate their effectiveness as readers. The intervention was also intended to assess my teaching, which was challenged by the need to deal with learners' poor levels of reading comprehension. The data was collected using the following research techniques: interviews, questionnaires, non-participant observation, learners' and researcher's journals, document analysis The data analysis revealed that a lack of resources to learn English; limited English language due to lack of exposure; and learners' lack of foundational knowledge from their primary schools were barriers to the successful teaching of comprehension strategies. Despite such barriers, however, this research provides evidence that teaching comprehension strategies can be effective if it is taught systematically, and applied continuously. Personally, I learnt that I had to modify my methods of teaching due to the response of learners to the lessons taught.
- Full Text:
Spatial and temporal patterns in the population and the feeding of Palaemon peringueyi (MacPherson 1990) (Decapoda, Palaemonidae) in the Kariega estuary, South Africa
- Nyalungu, Nonhlanhla Precotia Dudu
- Authors: Nyalungu, Nonhlanhla Precotia Dudu
- Date: 2013
- Subjects: Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5584 , http://hdl.handle.net/10962/d1001576 , Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Description: The spatial and temporal patterns in the population demographs and feeding ecology of the caridean shrimp, Palaemon peringueyi, was investigated over a 12 month period in the permanently open Kariega Estuary situated on the south-east coastline of South Africa. Shrimps were sampled monthly from three stations corresponding to the lower, middle and upper reaches of the Kariega Estuary. The shrimps were collected at the different stations using a pull net. Temperature, salinity, dissolved oxygen and % cover of submerged vegetation were measured at each sampling station. Finally, the feeding ecology of the shrimp was investigated employing stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes analysis. Temperature, salinity, dissolved oxygen and vegetation cover showed distinct seasonal patterns. The shrimps attained total abundances and biomass of between 0 and 245.6 individuals per m² (ind.m⁻²) and between 0 and 13.6 grams wet weight per m² (g wwt.m⁻²), respectively. Mean abundance ranged between 2.3 (± 3.0) and 88 (± 27.3) ind.m⁻² in the lower reach, between 0.9 (± 0.4) to 21.5 (± 4.5) ind.m⁻² in the middle reach and 0 to 1.6 (± 0.5) ind.m⁻² in the upper reach. Mean biomass ranged between 0.4 (± 0.5) and 4.4 (± 1.4) g wwt.m⁻² in the lower reach, between 0.1 (± 0) to 4.3 (± 0.9) g wwt.m⁻² in the middle reach and between 0 to 1.6 (± 0.5) g wwt.m⁻² in the upper reach. Greatest abundances and biomasses were recorded in winter following heavy rainfall within the catchment area. Freshwater inflow which is due to rainfall is thought to provide a cue for the recruitment of marine breeding organisms. The spatial patterns in the distribution of the shrimps showed that juveniles occupied the lower and middle reaches and adults the entire length of the estuary. There were no significant relationships between the abundance and biomass of the shrimps and the selected physico-chemical variables (p > 0.05 in all cases). Results of the stable isotope study indicated that the mean δ¹³C of the shrimps in the lower, middle and upper reaches were -12.4 (± 1.3) ‰, -15.6 (± 0.5) ‰ and -17.5 (± 0.5) ‰, respectively. The δ¹⁵N isotopes of the shrimps in the lower reach was 11.6 (± 0.5) ‰ with middle and upper reaches having similar δ¹⁵N values, 13.5 (± 0.4) ‰ and 13.4 (± 0.4) ‰, respectively. There was no significant difference in the δ¹³C and δ¹⁵N isotope (p > 0.05) between the sexes of the shrimps. Two-way ANOVA indicated a significant difference in the δ¹³C isotope of the shrimps between the sites (p < 0.05). The difference in the δ¹³C and δ¹⁵N ratios of the shrimps suggests spatial variability in the diet of P. peringueyi within the Kariega Estuary. The diet of the shrimps in the lower reach is primarily composed of Nanozostera capensis epibionts. In the middle reach the diet of the shrimps is likely comprised of the detritus of benthic algae. In the upper reach of the estuary, P. peringueyi likely derives its carbon from a combination of epibionts, benthic algae and detritus derived from Codium.
- Full Text:
- Authors: Nyalungu, Nonhlanhla Precotia Dudu
- Date: 2013
- Subjects: Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5584 , http://hdl.handle.net/10962/d1001576 , Palaemonidae -- Food -- South Africa , Palaemonidae -- Behavior -- South Africa , Palaemonidae -- Habitat -- South Africa , Estuarine biology -- South Africa , Shrimp populations -- South Africa , Shrimps -- South Africa , Decapoda (Crustacea) -- South Africa
- Description: The spatial and temporal patterns in the population demographs and feeding ecology of the caridean shrimp, Palaemon peringueyi, was investigated over a 12 month period in the permanently open Kariega Estuary situated on the south-east coastline of South Africa. Shrimps were sampled monthly from three stations corresponding to the lower, middle and upper reaches of the Kariega Estuary. The shrimps were collected at the different stations using a pull net. Temperature, salinity, dissolved oxygen and % cover of submerged vegetation were measured at each sampling station. Finally, the feeding ecology of the shrimp was investigated employing stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes analysis. Temperature, salinity, dissolved oxygen and vegetation cover showed distinct seasonal patterns. The shrimps attained total abundances and biomass of between 0 and 245.6 individuals per m² (ind.m⁻²) and between 0 and 13.6 grams wet weight per m² (g wwt.m⁻²), respectively. Mean abundance ranged between 2.3 (± 3.0) and 88 (± 27.3) ind.m⁻² in the lower reach, between 0.9 (± 0.4) to 21.5 (± 4.5) ind.m⁻² in the middle reach and 0 to 1.6 (± 0.5) ind.m⁻² in the upper reach. Mean biomass ranged between 0.4 (± 0.5) and 4.4 (± 1.4) g wwt.m⁻² in the lower reach, between 0.1 (± 0) to 4.3 (± 0.9) g wwt.m⁻² in the middle reach and between 0 to 1.6 (± 0.5) g wwt.m⁻² in the upper reach. Greatest abundances and biomasses were recorded in winter following heavy rainfall within the catchment area. Freshwater inflow which is due to rainfall is thought to provide a cue for the recruitment of marine breeding organisms. The spatial patterns in the distribution of the shrimps showed that juveniles occupied the lower and middle reaches and adults the entire length of the estuary. There were no significant relationships between the abundance and biomass of the shrimps and the selected physico-chemical variables (p > 0.05 in all cases). Results of the stable isotope study indicated that the mean δ¹³C of the shrimps in the lower, middle and upper reaches were -12.4 (± 1.3) ‰, -15.6 (± 0.5) ‰ and -17.5 (± 0.5) ‰, respectively. The δ¹⁵N isotopes of the shrimps in the lower reach was 11.6 (± 0.5) ‰ with middle and upper reaches having similar δ¹⁵N values, 13.5 (± 0.4) ‰ and 13.4 (± 0.4) ‰, respectively. There was no significant difference in the δ¹³C and δ¹⁵N isotope (p > 0.05) between the sexes of the shrimps. Two-way ANOVA indicated a significant difference in the δ¹³C isotope of the shrimps between the sites (p < 0.05). The difference in the δ¹³C and δ¹⁵N ratios of the shrimps suggests spatial variability in the diet of P. peringueyi within the Kariega Estuary. The diet of the shrimps in the lower reach is primarily composed of Nanozostera capensis epibionts. In the middle reach the diet of the shrimps is likely comprised of the detritus of benthic algae. In the upper reach of the estuary, P. peringueyi likely derives its carbon from a combination of epibionts, benthic algae and detritus derived from Codium.
- Full Text:
Photodynamic inactivation of Staphylococcus aureus using low symmetrically substituted phthalocyanines supported on a polystyrene polymer fiber
- Masilela, Nkosiphile, Kleyi, Phumelele, Tshentu, Zenixole, Priniotakis, Georgios, Westbroek, Philippe, Nyokong, Tebello
- Authors: Masilela, Nkosiphile , Kleyi, Phumelele , Tshentu, Zenixole , Priniotakis, Georgios , Westbroek, Philippe , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7330 , http://hdl.handle.net/10962/d1020591
- Description: This work reports on the antimicrobial photo-activities of a series of low symmetrically substituted phthalocyanine complexes in solution and in a fiber matrix. Phthalocyanine complexes were successfully electrospun into a polystyrene polymer. The fiber diameter ranged from 240 nm to 390 nm in average. The modified polymer fiber showed successful singlet oxygen production with the Ge monocarboxy phthalocyanine modified fiber giving the highest singlet oxygen quantum yield value of 0.46 due to lack of aggregation when in the polymer. All the unsymmetrically substituted complexes showed antimicrobial activity towards S. Aureus under illumination with visible light. The symmetrical ZnPc and ZnTPCPc showed no activity under illumination with light in the fiber matrix due to low singlet oxygen production. , Original publication is available at http://dx.doi.org/10.1016/j.dyepig.2012.10.001
- Full Text: false
- Authors: Masilela, Nkosiphile , Kleyi, Phumelele , Tshentu, Zenixole , Priniotakis, Georgios , Westbroek, Philippe , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7330 , http://hdl.handle.net/10962/d1020591
- Description: This work reports on the antimicrobial photo-activities of a series of low symmetrically substituted phthalocyanine complexes in solution and in a fiber matrix. Phthalocyanine complexes were successfully electrospun into a polystyrene polymer. The fiber diameter ranged from 240 nm to 390 nm in average. The modified polymer fiber showed successful singlet oxygen production with the Ge monocarboxy phthalocyanine modified fiber giving the highest singlet oxygen quantum yield value of 0.46 due to lack of aggregation when in the polymer. All the unsymmetrically substituted complexes showed antimicrobial activity towards S. Aureus under illumination with visible light. The symmetrical ZnPc and ZnTPCPc showed no activity under illumination with light in the fiber matrix due to low singlet oxygen production. , Original publication is available at http://dx.doi.org/10.1016/j.dyepig.2012.10.001
- Full Text: false
Movement patterns and genetic stock delineation of an endemic South African sparid, the Poenskop, Cymatoceps nasutus (Castelnau, 1861)
- Authors: Murray, Taryn Sara
- Date: 2013
- Subjects: Fish stock assessment -- South Africa , Sparidae -- South Africa , Fishes -- Reproduction -- South Africa , Fishing -- South Africa , Fish populations -- South Africa , Fishes -- Behavior -- South Africa , Marine fishes -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5178 , http://hdl.handle.net/10962/d1001514 , Fish stock assessment -- South Africa , Sparidae -- South Africa , Fishes -- Reproduction -- South Africa , Fishing -- South Africa , Fish populations -- South Africa , Fishes -- Behavior -- South Africa , Marine fishes -- South Africa
- Description: Poenskop Cymatoceps nasutus (Pisces: Sparidae), an endemic South African sparid, is an important angling species being predominantly targeted by the recreational shore and skiboat sector. This species is slow-growing, long-lived, late-maturing and sex-changing, making poenskop acutely sensitive to over-exploitation. Despite interventions, such as the imposition of size and bag limits (currently 50 cm TL and one per licensed fisher per day) by authorities, catch-per-unit-effort trends reflect a severe and consistent stock decline over the last two decades. Poenskop has been identified as a priority species for research and conservation. Although the biology and population dynamics of this species have been well-documented, little is known about the movement behaviour of poenskop. Furthermore, there is a complete lack of information on its genetic stock structure. This thesis aimed to address the current knowledge gaps concerning movement behaviour and genetic stock structure of poenskop, making use of a range of methods and drawing on available information, including available fishery records as well as published and unpublished survey and research data, and data from long-term monitoring programmes. Analysis of available catch data (published and unpublished) revealed a decline in the number of poenskop caught as well as size of fish taken over the last two decades, ultimately reflecting the collapse of the stock (estimated to be at 20% of their pristine level). Improved catch-per-unit-effort data from the Tsitsikamma National Park Marine Protected Area (MPA), and larger poenskop being caught in the no-take areas than adjacent exploited areas of the Pondoland MPA confirmed that MPAs can be effective for the protection and management of poenskop. The current MPA network in South Africa is already wellestablished, and encompasses considerable reef areas, being preferable for poenskop habitation. Conventional dart tagging and recapture information from three ongoing, long-term fishtagging projects, conducted throughout the poenskop’s distribution, indicated high levels of residency at all life-history stages. Coastal region, seasonality and time at recapture did not appear to have a significant effect on the level of movement or distance moved. However, on examining the relationship among coastal movements and fish size and ages, larger and older fish (adults) moved greater distances, with juveniles and sub-adults showing high degrees of residency. An estimation of home-range size indicated smaller poenskop to hold smaller home-ranges, while larger poenskop hold larger home-ranges. Large easterly displacements of a number of adult poenskop is in accordance with previous findings that this species may undertake a unidirectional migration up the coastline of South Africa where they possibly settle in Transkei waters for the remainder of their lives. This high level of residency makes poenskop vulnerable to localised depletion, although they can be effectively protected by suitable MPAs. Despite considerable tagging effort along the South African coastline (2 704 poenskop tagged with 189 recaptures, between 1984 and 2010), there remains limited information on the connectivity of different regions along the South African coastline. This was addressed using mitochondrial DNA sequencing. The mitochondrial DNA control region was used due to its high substitution rate, haploid nature, maternal inheritance and absence of recombination. The mtDNA sequencing showed no evidence of major geographic barriers to gene flow in this species. Samples collected throughout the core distribution of poenskop showed high genetic diversity (h = 0.88, π = 0.01), low genetic differentiation among regions, no spatial structure (ɸST = 0.012, p = 0.208) and no evidence of isolation by distance. The collapsed stock status of poenskop as well as the fact that it is being actively targeted by recreational and commercial fishers suggests that this species requires improved management, with consideration given to its life-history style, residency and poor conservation status. Management recommendations for poenskop, combined with increasing South Africa’s existing MPA network, include the possibility of setting up a closed season (during known spawning periods) as well as the decommercialisation of this species. The techniques used and developed in this study can also be adopted for other overexploited linefish species.
- Full Text:
- Authors: Murray, Taryn Sara
- Date: 2013
- Subjects: Fish stock assessment -- South Africa , Sparidae -- South Africa , Fishes -- Reproduction -- South Africa , Fishing -- South Africa , Fish populations -- South Africa , Fishes -- Behavior -- South Africa , Marine fishes -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5178 , http://hdl.handle.net/10962/d1001514 , Fish stock assessment -- South Africa , Sparidae -- South Africa , Fishes -- Reproduction -- South Africa , Fishing -- South Africa , Fish populations -- South Africa , Fishes -- Behavior -- South Africa , Marine fishes -- South Africa
- Description: Poenskop Cymatoceps nasutus (Pisces: Sparidae), an endemic South African sparid, is an important angling species being predominantly targeted by the recreational shore and skiboat sector. This species is slow-growing, long-lived, late-maturing and sex-changing, making poenskop acutely sensitive to over-exploitation. Despite interventions, such as the imposition of size and bag limits (currently 50 cm TL and one per licensed fisher per day) by authorities, catch-per-unit-effort trends reflect a severe and consistent stock decline over the last two decades. Poenskop has been identified as a priority species for research and conservation. Although the biology and population dynamics of this species have been well-documented, little is known about the movement behaviour of poenskop. Furthermore, there is a complete lack of information on its genetic stock structure. This thesis aimed to address the current knowledge gaps concerning movement behaviour and genetic stock structure of poenskop, making use of a range of methods and drawing on available information, including available fishery records as well as published and unpublished survey and research data, and data from long-term monitoring programmes. Analysis of available catch data (published and unpublished) revealed a decline in the number of poenskop caught as well as size of fish taken over the last two decades, ultimately reflecting the collapse of the stock (estimated to be at 20% of their pristine level). Improved catch-per-unit-effort data from the Tsitsikamma National Park Marine Protected Area (MPA), and larger poenskop being caught in the no-take areas than adjacent exploited areas of the Pondoland MPA confirmed that MPAs can be effective for the protection and management of poenskop. The current MPA network in South Africa is already wellestablished, and encompasses considerable reef areas, being preferable for poenskop habitation. Conventional dart tagging and recapture information from three ongoing, long-term fishtagging projects, conducted throughout the poenskop’s distribution, indicated high levels of residency at all life-history stages. Coastal region, seasonality and time at recapture did not appear to have a significant effect on the level of movement or distance moved. However, on examining the relationship among coastal movements and fish size and ages, larger and older fish (adults) moved greater distances, with juveniles and sub-adults showing high degrees of residency. An estimation of home-range size indicated smaller poenskop to hold smaller home-ranges, while larger poenskop hold larger home-ranges. Large easterly displacements of a number of adult poenskop is in accordance with previous findings that this species may undertake a unidirectional migration up the coastline of South Africa where they possibly settle in Transkei waters for the remainder of their lives. This high level of residency makes poenskop vulnerable to localised depletion, although they can be effectively protected by suitable MPAs. Despite considerable tagging effort along the South African coastline (2 704 poenskop tagged with 189 recaptures, between 1984 and 2010), there remains limited information on the connectivity of different regions along the South African coastline. This was addressed using mitochondrial DNA sequencing. The mitochondrial DNA control region was used due to its high substitution rate, haploid nature, maternal inheritance and absence of recombination. The mtDNA sequencing showed no evidence of major geographic barriers to gene flow in this species. Samples collected throughout the core distribution of poenskop showed high genetic diversity (h = 0.88, π = 0.01), low genetic differentiation among regions, no spatial structure (ɸST = 0.012, p = 0.208) and no evidence of isolation by distance. The collapsed stock status of poenskop as well as the fact that it is being actively targeted by recreational and commercial fishers suggests that this species requires improved management, with consideration given to its life-history style, residency and poor conservation status. Management recommendations for poenskop, combined with increasing South Africa’s existing MPA network, include the possibility of setting up a closed season (during known spawning periods) as well as the decommercialisation of this species. The techniques used and developed in this study can also be adopted for other overexploited linefish species.
- Full Text:
A social realist account of the tutorial system at the University of Johannesburg
- Authors: Layton, Delia Melanie
- Date: 2013
- Subjects: University of Johannesburg Education, Higher -- South Africa Tutors and tutoring -- South Africa College teaching -- South Africa Archer, Margaret Scotford College student development programs -- South Africa Social realism , Tutorial system
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1314 , http://hdl.handle.net/10962/d1001621
- Description: Using Margaret Archer’s social realist methodology, this study critically examines the construction of the tutorial system in several departments and faculties at the Auckland Park campus of the University of Johannesburg. The purpose of the study is to investigate the extent to which tutorials support the acquisition of programme and disciplinary epistemologies. Social realism calls for analytical dualism of ‘the people’ (agents) from ‘the parts’ (structure and culture). This requires the separate consideration of structures (social systems, rules, roles, practices, policies, institutions, and organisational structures like committees, units, departments, faculties), culture (ideologies, theories, beliefs and values as evidenced in discourses), and agency (people and their ability to act within and upon their own world in terms of their social roles and positions dependent on their ability to activate their emergent properties and powers). Through this investigation, an understanding was gained into how the emergent properties and powers contained within the material, ideational and agential elements helped to generate certain events and practices in the tutorial system. These generative mechanisms were examined to explore whether they enabled or constrained the construction of the tutorial system to provide epistemological access. The study shows that while many official policy documents construct the tutorial system as being an intervention to support academic success, particularly for first-years, there are some tensions within the document discourses, where, on the one hand, student success is constructed in terms of throughput numbers, or, on the other hand, as being about becoming a particular kind of person who is able to access and add to powerful knowledge. Furthermore, the study found that policies are not being consistently implemented. While certain key agents and actors, in the form of management, academics and tutors, were found to be able to overcome constraints and introduce innovative ways of enhancing access to target epistemologies, there is a need for consideration of structural and cultural constraints. For example, structures in the form of funding, venues and timetabling were found to constrain the tutorial system as did some of the discourses in the cultural domain: for example, in the form of certain dominant discourses around teaching and learning, beliefs about the purpose of the tutorial and the relationship between academics and the tutorial system. The study also found that the ontological aspects of ‘learning to be’ were not fore-grounded to any great extent in the ways in which the tutorial system was constructed. There needs to be more consideration of the ontological as well as the epistemological aspects of first-year study so as to take cognisance of the different learning needs of an increasingly diverse student body and to encourage the development of the student agency necessary for a deep engagement with the disciplinary epistemologies.
- Full Text:
- Authors: Layton, Delia Melanie
- Date: 2013
- Subjects: University of Johannesburg Education, Higher -- South Africa Tutors and tutoring -- South Africa College teaching -- South Africa Archer, Margaret Scotford College student development programs -- South Africa Social realism , Tutorial system
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1314 , http://hdl.handle.net/10962/d1001621
- Description: Using Margaret Archer’s social realist methodology, this study critically examines the construction of the tutorial system in several departments and faculties at the Auckland Park campus of the University of Johannesburg. The purpose of the study is to investigate the extent to which tutorials support the acquisition of programme and disciplinary epistemologies. Social realism calls for analytical dualism of ‘the people’ (agents) from ‘the parts’ (structure and culture). This requires the separate consideration of structures (social systems, rules, roles, practices, policies, institutions, and organisational structures like committees, units, departments, faculties), culture (ideologies, theories, beliefs and values as evidenced in discourses), and agency (people and their ability to act within and upon their own world in terms of their social roles and positions dependent on their ability to activate their emergent properties and powers). Through this investigation, an understanding was gained into how the emergent properties and powers contained within the material, ideational and agential elements helped to generate certain events and practices in the tutorial system. These generative mechanisms were examined to explore whether they enabled or constrained the construction of the tutorial system to provide epistemological access. The study shows that while many official policy documents construct the tutorial system as being an intervention to support academic success, particularly for first-years, there are some tensions within the document discourses, where, on the one hand, student success is constructed in terms of throughput numbers, or, on the other hand, as being about becoming a particular kind of person who is able to access and add to powerful knowledge. Furthermore, the study found that policies are not being consistently implemented. While certain key agents and actors, in the form of management, academics and tutors, were found to be able to overcome constraints and introduce innovative ways of enhancing access to target epistemologies, there is a need for consideration of structural and cultural constraints. For example, structures in the form of funding, venues and timetabling were found to constrain the tutorial system as did some of the discourses in the cultural domain: for example, in the form of certain dominant discourses around teaching and learning, beliefs about the purpose of the tutorial and the relationship between academics and the tutorial system. The study also found that the ontological aspects of ‘learning to be’ were not fore-grounded to any great extent in the ways in which the tutorial system was constructed. There needs to be more consideration of the ontological as well as the epistemological aspects of first-year study so as to take cognisance of the different learning needs of an increasingly diverse student body and to encourage the development of the student agency necessary for a deep engagement with the disciplinary epistemologies.
- Full Text: