A study on the role of the media in identity formation among isiXhosa speaking youth in Grahamstown with focus on SABC’s Yo TV
- Authors: Mabusela, Pumeza
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3661 , http://hdl.handle.net/10962/d1021302
- Description: This study explores the use of African languages, more specifically isiXhosa, in the South African Broadcasting Corporation (SABC). It does this by investigating the YO TV programme and its impact on identity formation amongst isiXhosa speaking youth. The research was conducted in Grahamstown which is located in the Eastern Cape province of South Africa. Young isiXhosa speakers were used as participants for questionnaires and focus group interviews. The location of the study within the Eastern Cape was driven by the fact that Grahamstown consists of mainly isiXhosa speakers, and young people are a big part of the population. Secondly, the participants were chosen in order to look at how isiXhosa and the Xhosa culture are represented in the YO TV programme through the lenses of young people who speak the language, and whether the representation of these two aspects plays a role in the formation of their identity. The goals of the research were to explore the relationship between language and youth identity, and the role of television in the construction of this identity. The research looked at the SABC’s YO TV which is a youth programme targeting South African youth who speak different languages and the role it plays in constructing the identity of isiXhosa speaking youth in relation to language and culture. It also examined for what purpose isiXhosa was used in the YO TV programme. The study further identified and critically analysed the already existing strategies used by the SABC to promote African languages in youth programs. The study made several findings, one of these being that there is a relationship that exists between language, culture and identity. As a result of this relationship, this study found that when one of these aspects is less represented on television, it affects the other(s). Thus, little representation of isiXhosa on YO TV has an impact on the identity formation of young isiXhosa speakers as they believe that language and culture are a part of who they are, their identity. This study also discovered that institutions of power such as the media play a key role in affirming the identity of young people. They play a role in influencing the way young people reason and do things. This study argues that television programmes such as the YO TV programme must use African languages, as well as English because the use of African languages adds value to how young people perceive them. The use of African languages on television will contribute to their growth and development. Moreover, the use of these languages in the media contributes in identity construction of young African language speakers.
- Full Text:
- Authors: Mabusela, Pumeza
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3661 , http://hdl.handle.net/10962/d1021302
- Description: This study explores the use of African languages, more specifically isiXhosa, in the South African Broadcasting Corporation (SABC). It does this by investigating the YO TV programme and its impact on identity formation amongst isiXhosa speaking youth. The research was conducted in Grahamstown which is located in the Eastern Cape province of South Africa. Young isiXhosa speakers were used as participants for questionnaires and focus group interviews. The location of the study within the Eastern Cape was driven by the fact that Grahamstown consists of mainly isiXhosa speakers, and young people are a big part of the population. Secondly, the participants were chosen in order to look at how isiXhosa and the Xhosa culture are represented in the YO TV programme through the lenses of young people who speak the language, and whether the representation of these two aspects plays a role in the formation of their identity. The goals of the research were to explore the relationship between language and youth identity, and the role of television in the construction of this identity. The research looked at the SABC’s YO TV which is a youth programme targeting South African youth who speak different languages and the role it plays in constructing the identity of isiXhosa speaking youth in relation to language and culture. It also examined for what purpose isiXhosa was used in the YO TV programme. The study further identified and critically analysed the already existing strategies used by the SABC to promote African languages in youth programs. The study made several findings, one of these being that there is a relationship that exists between language, culture and identity. As a result of this relationship, this study found that when one of these aspects is less represented on television, it affects the other(s). Thus, little representation of isiXhosa on YO TV has an impact on the identity formation of young isiXhosa speakers as they believe that language and culture are a part of who they are, their identity. This study also discovered that institutions of power such as the media play a key role in affirming the identity of young people. They play a role in influencing the way young people reason and do things. This study argues that television programmes such as the YO TV programme must use African languages, as well as English because the use of African languages adds value to how young people perceive them. The use of African languages on television will contribute to their growth and development. Moreover, the use of these languages in the media contributes in identity construction of young African language speakers.
- Full Text:
A survey of employee preferences in the design of a performance management system
- Authors: Keshave, Hiten
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:863 , http://hdl.handle.net/10962/d1021180
- Description: This thesis begins with an introduction to performance management and the intended aim and objective of the research. Thereafter literature findings relative to performance management and performance management systems are discussed. In the review of literature, three processes that could be implemented in a performance management system were highlighted, namely; (1) the planning process, (2) the monitoring and development process, and (3) an annual summative and feedback process. Performance management functions deemed important to employees during each process of the performance management system were identified and discussed. Subsequent to the literature review, the research methodology was described and involved the implementation of quantitative research within a post-positivist paradigm in the form of a close-ended survey questionnaire. Analysis of the data involved a gap analysis and needs analysis. The gap analysis study was based on the opinion of management respondents in comparison to the opinion of non-management respondents. Results of the gap analysis were determined based on the calculation of an importance score for each sub-group. The needs analysis study was based on the overall opinion of all respondents, and results were determined based on the calculation of an overall importance score. In light of the literature review that was conducted to inform the questionnaire design, the survey results supported the literature review of each discussed performance management function with no evident contradictions. The results of the gap analysis and needs analysis were satisfactorily met for each performance management function. On the basis of these findings, it was assumed that all the performance management functions identified in the literature are important and could be implemented in the design of a performance management system. The results highlighted the importance of a performance plan and development plan to underpin the performance management system.
- Full Text:
- Authors: Keshave, Hiten
- Date: 2016
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:863 , http://hdl.handle.net/10962/d1021180
- Description: This thesis begins with an introduction to performance management and the intended aim and objective of the research. Thereafter literature findings relative to performance management and performance management systems are discussed. In the review of literature, three processes that could be implemented in a performance management system were highlighted, namely; (1) the planning process, (2) the monitoring and development process, and (3) an annual summative and feedback process. Performance management functions deemed important to employees during each process of the performance management system were identified and discussed. Subsequent to the literature review, the research methodology was described and involved the implementation of quantitative research within a post-positivist paradigm in the form of a close-ended survey questionnaire. Analysis of the data involved a gap analysis and needs analysis. The gap analysis study was based on the opinion of management respondents in comparison to the opinion of non-management respondents. Results of the gap analysis were determined based on the calculation of an importance score for each sub-group. The needs analysis study was based on the overall opinion of all respondents, and results were determined based on the calculation of an overall importance score. In light of the literature review that was conducted to inform the questionnaire design, the survey results supported the literature review of each discussed performance management function with no evident contradictions. The results of the gap analysis and needs analysis were satisfactorily met for each performance management function. On the basis of these findings, it was assumed that all the performance management functions identified in the literature are important and could be implemented in the design of a performance management system. The results highlighted the importance of a performance plan and development plan to underpin the performance management system.
- Full Text:
Abstract art and the contested ground of African modernisms
- Authors: Mumba, Patrick
- Date: 2016
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2515 , http://hdl.handle.net/10962/d1021165
- Description: This submission for a Masters of Fine Art consists of a thesis titled Abstract Art and the Contested Ground of African Modernisms developed as a document to support the exhibition Time in Between. The exhibition addresses the fact that nothing is permanent in life, and uses abstract paintings that reveal in-between time through an engagement with the processes of ageing and decaying. Life is always a temporary situation, an idea which I develop as Time in Between, the beginning and the ending, the young and the aged, the new and the old. In my painting practice I break down these dichotomies, questioning how abstractions engage with the relative notion of time and how this links to the processes of ageing and decaying in life. I relate this ageing process to the aesthetic process of moving from representational art to semi-abstract art, and to complete abstraction, when the object or material reaches a wholly unrecognisable stage. My practice is concerned not only with the aesthetics of these paintings but also, more importantly, with translating each specific theme into the formal qualities of abstraction. In my thesis I analyse abstraction in relation to ‘African Modernisms’ and critique the notion that African abstraction is not ‘African’ but a mere copy of Western Modernism. In response to this notion, I have used a study of abstraction to interrogate notions of so-called ‘African-ness’ or ‘Zambian-ness’, whilst simultaneously challenging the Western stereotypical view of African modern art. I have also related the theoretical and practical analysis of abstraction to scholarly debates on abstraction and ‘African Modernism’, arguing for multiple African Modernisms.
- Full Text:
- Authors: Mumba, Patrick
- Date: 2016
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2515 , http://hdl.handle.net/10962/d1021165
- Description: This submission for a Masters of Fine Art consists of a thesis titled Abstract Art and the Contested Ground of African Modernisms developed as a document to support the exhibition Time in Between. The exhibition addresses the fact that nothing is permanent in life, and uses abstract paintings that reveal in-between time through an engagement with the processes of ageing and decaying. Life is always a temporary situation, an idea which I develop as Time in Between, the beginning and the ending, the young and the aged, the new and the old. In my painting practice I break down these dichotomies, questioning how abstractions engage with the relative notion of time and how this links to the processes of ageing and decaying in life. I relate this ageing process to the aesthetic process of moving from representational art to semi-abstract art, and to complete abstraction, when the object or material reaches a wholly unrecognisable stage. My practice is concerned not only with the aesthetics of these paintings but also, more importantly, with translating each specific theme into the formal qualities of abstraction. In my thesis I analyse abstraction in relation to ‘African Modernisms’ and critique the notion that African abstraction is not ‘African’ but a mere copy of Western Modernism. In response to this notion, I have used a study of abstraction to interrogate notions of so-called ‘African-ness’ or ‘Zambian-ness’, whilst simultaneously challenging the Western stereotypical view of African modern art. I have also related the theoretical and practical analysis of abstraction to scholarly debates on abstraction and ‘African Modernism’, arguing for multiple African Modernisms.
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Academic literacy and the decontextualised learner
- Boughey, Chrissie, McKenna, Sioux
- Authors: Boughey, Chrissie , McKenna, Sioux
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64651 , vital:28585 , http://www.DOI:10.14426/cristal.v4i2.80
- Description: The literacy practices that are valued in the university emerge from specific disciplinary histories yet students are often expected to master these as if they were common sense and natural. This article argues that the autonomous model of literacy, which sees language use as the application of a set of neutral skills, continues to dominate in South African universities. This model denies the extent to which taking on disciplinary literacy practices can be difficult and have implications for identity. It also allows disciplinary norms to remain largely opaque and beyond critique. Furthermore, the autonomous model of literacy is often coupled with a discourse of the ‘decontextualised learner’ who is divorced from her social context, with higher education success seen to be resting largely upon attributes inherent in, or lacking from, the individual. Sadly, alternative critical social understandings have not been widely taken up despite their being well researched. Indeed, such understandings have often been misappropriated in ways that draw on critical social terminology to offer autonomous, decontextualised, remedial student interventions. We argue that these issues are implicated in students’ accusations that universities are alienating spaces.
- Full Text:
- Authors: Boughey, Chrissie , McKenna, Sioux
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64651 , vital:28585 , http://www.DOI:10.14426/cristal.v4i2.80
- Description: The literacy practices that are valued in the university emerge from specific disciplinary histories yet students are often expected to master these as if they were common sense and natural. This article argues that the autonomous model of literacy, which sees language use as the application of a set of neutral skills, continues to dominate in South African universities. This model denies the extent to which taking on disciplinary literacy practices can be difficult and have implications for identity. It also allows disciplinary norms to remain largely opaque and beyond critique. Furthermore, the autonomous model of literacy is often coupled with a discourse of the ‘decontextualised learner’ who is divorced from her social context, with higher education success seen to be resting largely upon attributes inherent in, or lacking from, the individual. Sadly, alternative critical social understandings have not been widely taken up despite their being well researched. Indeed, such understandings have often been misappropriated in ways that draw on critical social terminology to offer autonomous, decontextualised, remedial student interventions. We argue that these issues are implicated in students’ accusations that universities are alienating spaces.
- Full Text:
Accelerated development programmes for Black academics: Interrupting or reproducing social and cultural dominance?
- Authors: Booi, Masixole
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3338 , vital:20483
- Description: A wide body of research literature on transformation of higher education institutions in South Africa has focused on institutional reform and restructuring, change in employment legislation and policies, transforming institutional culture(s) and student and staff demographics (Portnoi, 2009:373; Viljoen and Rothmann, 2002:3; Badat, 2007; 2010; Cloete, Muller, Makgoba and Ekong, 1997; Nieman, 2010). The literature on transformation of higher education institutions shows that the underrepresentation, recruiting and retaining of blacks and women in senior posts is still the major challenge faced by the project of transforming higher education, particularly in Historically White Institutions (HWIs). Universities have introduced a variety of ‘accelerated development’ programmes to meet this challenge and accelerate the entry into academia of black academics. The present study draws on Pierre Bourdieu’s notions of cultural capital, field and social capital to interpret the lived experiences of participants in the Accelerated Development Programme (ADP) of one HWI. In particular the study is interested in how, in the participants’ experience, they, as members of the programme, have or have not been able to contribute to the transformation of the culture(s) of the institution. The study critically examines the assumption that the institutional practices, values and norms can be changed only by socialising ‘new’ lecturers into an already existing dominant culture rather than seeing the need to socialise existing lecturers into a new culture informed by a democratic ethos.
- Full Text:
- Authors: Booi, Masixole
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3338 , vital:20483
- Description: A wide body of research literature on transformation of higher education institutions in South Africa has focused on institutional reform and restructuring, change in employment legislation and policies, transforming institutional culture(s) and student and staff demographics (Portnoi, 2009:373; Viljoen and Rothmann, 2002:3; Badat, 2007; 2010; Cloete, Muller, Makgoba and Ekong, 1997; Nieman, 2010). The literature on transformation of higher education institutions shows that the underrepresentation, recruiting and retaining of blacks and women in senior posts is still the major challenge faced by the project of transforming higher education, particularly in Historically White Institutions (HWIs). Universities have introduced a variety of ‘accelerated development’ programmes to meet this challenge and accelerate the entry into academia of black academics. The present study draws on Pierre Bourdieu’s notions of cultural capital, field and social capital to interpret the lived experiences of participants in the Accelerated Development Programme (ADP) of one HWI. In particular the study is interested in how, in the participants’ experience, they, as members of the programme, have or have not been able to contribute to the transformation of the culture(s) of the institution. The study critically examines the assumption that the institutional practices, values and norms can be changed only by socialising ‘new’ lecturers into an already existing dominant culture rather than seeing the need to socialise existing lecturers into a new culture informed by a democratic ethos.
- Full Text:
Acoustic biosensors
- Fogel, Ronen, Limson, Janice L, Seshia, Ashwin A
- Authors: Fogel, Ronen , Limson, Janice L , Seshia, Ashwin A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431648 , vital:72793 , xlink:href="https://doi.org/10.1042/EBC20150011"
- Description: Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.
- Full Text:
- Authors: Fogel, Ronen , Limson, Janice L , Seshia, Ashwin A
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431648 , vital:72793 , xlink:href="https://doi.org/10.1042/EBC20150011"
- Description: Resonant and acoustic wave devices have been researched for several decades for application in the gravimetric sensing of a variety of biological and chemical analytes. These devices operate by coupling the measurand (e.g. analyte adsorption) as a modulation in the physical properties of the acoustic wave (e.g. resonant frequency, acoustic velocity, dissipation) that can then be correlated with the amount of adsorbed analyte. These devices can also be miniaturized with advantages in terms of cost, size and scalability, as well as potential additional features including integration with microfluidics and electronics, scaled sensitivities associated with smaller dimensions and higher operational frequencies, the ability to multiplex detection across arrays of hundreds of devices embedded in a single chip, increased throughput and the ability to interrogate a wider range of modes including within the same device. Additionally, device fabrication is often compatible with semiconductor volume batch manufacturing techniques enabling cost scalability and a high degree of precision and reproducibility in the manufacturing process. Integration with microfluidics handling also enables suitable sample pre-processing/separation/purification/amplification steps that could improve selectivity and the overall signal-to-noise ratio. Three device types are reviewed here: (i) bulk acoustic wave sensors, (ii) surface acoustic wave sensors, and (iii) micro/nano-electromechanical system (MEMS/NEMS) sensors.
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Across developmental state and social compacting: the peculiar case of South Africa
- Authors: Fine, Ben
- Date: 2016
- Subjects: Economic development -- South Africa South Africa -- Economic conditions National Development Plan -- South Africa South Africa -- Social policy Economic development -- Political aspects -- South Africa
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/3082 , vital:20367 , ISBN 9780868106090
- Description: This paper is concerned with the shifting fortunes of the Developmental State Paradigm (DSP) and the Social Compacting Paradigm (SCP) and, with some reference to South Africa, how they do or do not have continuing presence and relevance. For each, there is a dual trajectory in terms of an evolving intellectual content, on the one hand, and an evolving set of global and national circumstances on the other. I show that both paradigms have increasingly diverged from the material realities that they are intended to confront. This is primarily because of the neglect of financialisation as the key characteristic of the past thirty years, which itself underpins neo-liberalism. Whilst, in the post-war boom, both developmentalism and neo-corporatism offered some purchase on material realities and the prospects for policymaking, this has been eroded or, more exactly, transformed by financialisation. Unless the latter is satisfactorily addressed, neither development nor compacting can be expected to succeed, or be progressive, in any meaningful sense.
- Full Text:
- Authors: Fine, Ben
- Date: 2016
- Subjects: Economic development -- South Africa South Africa -- Economic conditions National Development Plan -- South Africa South Africa -- Social policy Economic development -- Political aspects -- South Africa
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/3082 , vital:20367 , ISBN 9780868106090
- Description: This paper is concerned with the shifting fortunes of the Developmental State Paradigm (DSP) and the Social Compacting Paradigm (SCP) and, with some reference to South Africa, how they do or do not have continuing presence and relevance. For each, there is a dual trajectory in terms of an evolving intellectual content, on the one hand, and an evolving set of global and national circumstances on the other. I show that both paradigms have increasingly diverged from the material realities that they are intended to confront. This is primarily because of the neglect of financialisation as the key characteristic of the past thirty years, which itself underpins neo-liberalism. Whilst, in the post-war boom, both developmentalism and neo-corporatism offered some purchase on material realities and the prospects for policymaking, this has been eroded or, more exactly, transformed by financialisation. Unless the latter is satisfactorily addressed, neither development nor compacting can be expected to succeed, or be progressive, in any meaningful sense.
- Full Text:
Active Layer Dynamics at Four Borehole Sites in Western Dronning Maud Land, Antarctica
- Authors: Kotzé, Camilla
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4894 , http://hdl.handle.net/10962/d1021295
- Description: Permafrost and active layer dynamics in the Antarctic play an important role within terrestrial landscapes and ecosystems and as a climate change indicator. However, they remain less thoroughly researched than their Northern-Hemispheric counterpart. Despite advancements made by ANTPAS on the permafrost and active layer monitoring network in the Antarctic, observational gaps still exist. Western Dronning Maud Land (WDML) has been identified as one of these gaps, necessitating further research on permafrost dynamics and the influence of climate parameters thereon. Such elucidation is critical to both the cryospheric and life sciences. Variations in the surface climate of Antarctica can be seen as a result of inter-annual variations in atmospheric circulation, enhancing permafrost degradation and active layer thickening which directly affects soil processes, such as sorting and cryoturbation. Ground temperatures from four permafrost boreholes from WDML were analysed from 2007 to 2014. The study sites exhibit seasonal freezing, periglacial landforms, and altitudinal variation, ranging between ca. 450masl to ca. 1300masl. Using ground thermal regime and regional climate data, the spatial and temporal variability of the active layer in the Ahlmannryggen and Jutulsessen areas of WDML were characterised. 137 Cs tracing has revealed that the active layer and associated landforms have been active over the past half century. Further results show that active layer depths at each site vary inter-annually and are particularly influenced by snow cover, altitude and distance to the ice-shelf. Moreover, a correlation between the SAO (Semi-Annual Oscillation) and measured ground temperatures was found, principally during the transitional season of the SAO in May and September. The relationship between climate and ground thermal regimes, especially the influence of teleconnections thereon, is essential to improving the understanding of permafrost dynamics and landform morphology in continental Antarctica.
- Full Text:
- Authors: Kotzé, Camilla
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4894 , http://hdl.handle.net/10962/d1021295
- Description: Permafrost and active layer dynamics in the Antarctic play an important role within terrestrial landscapes and ecosystems and as a climate change indicator. However, they remain less thoroughly researched than their Northern-Hemispheric counterpart. Despite advancements made by ANTPAS on the permafrost and active layer monitoring network in the Antarctic, observational gaps still exist. Western Dronning Maud Land (WDML) has been identified as one of these gaps, necessitating further research on permafrost dynamics and the influence of climate parameters thereon. Such elucidation is critical to both the cryospheric and life sciences. Variations in the surface climate of Antarctica can be seen as a result of inter-annual variations in atmospheric circulation, enhancing permafrost degradation and active layer thickening which directly affects soil processes, such as sorting and cryoturbation. Ground temperatures from four permafrost boreholes from WDML were analysed from 2007 to 2014. The study sites exhibit seasonal freezing, periglacial landforms, and altitudinal variation, ranging between ca. 450masl to ca. 1300masl. Using ground thermal regime and regional climate data, the spatial and temporal variability of the active layer in the Ahlmannryggen and Jutulsessen areas of WDML were characterised. 137 Cs tracing has revealed that the active layer and associated landforms have been active over the past half century. Further results show that active layer depths at each site vary inter-annually and are particularly influenced by snow cover, altitude and distance to the ice-shelf. Moreover, a correlation between the SAO (Semi-Annual Oscillation) and measured ground temperatures was found, principally during the transitional season of the SAO in May and September. The relationship between climate and ground thermal regimes, especially the influence of teleconnections thereon, is essential to improving the understanding of permafrost dynamics and landform morphology in continental Antarctica.
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Adaptable exploit detection through scalable netflow analysis
- Herbert, Alan, Irwin, Barry V W
- Authors: Herbert, Alan , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429274 , vital:72572 , https://ieeexplore.ieee.org/abstract/document/7802938
- Description: Full packet analysis on firewalls and intrusion detection, although effective, has been found in recent times to be detrimental to the overall performance of networks that receive large volumes of throughput. For this reason partial packet analysis technologies such as the NetFlow protocol have emerged to better mitigate these bottlenecks through log generation. This paper researches the use of log files generated by NetFlow version 9 and IPFIX to identify successful and unsuccessful exploit attacks commonly used by automated systems. These malicious communications include but are not limited to exploits that attack Microsoft RPC, Samba, NTP (Network Time Protocol) and IRC (Internet Relay Chat). These attacks are recreated through existing exploit implementations on Metasploit and through hand-crafted reconstructions of exploits via known documentation of vulnerabilities. These attacks are then monitored through a preconfigured virtual testbed containing gateways and network connections commonly found on the Internet. This common attack identification system is intended for insertion as a parallel module for Bolvedere in order to further the increase the Bolvedere system's attack detection capability.
- Full Text:
- Authors: Herbert, Alan , Irwin, Barry V W
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429274 , vital:72572 , https://ieeexplore.ieee.org/abstract/document/7802938
- Description: Full packet analysis on firewalls and intrusion detection, although effective, has been found in recent times to be detrimental to the overall performance of networks that receive large volumes of throughput. For this reason partial packet analysis technologies such as the NetFlow protocol have emerged to better mitigate these bottlenecks through log generation. This paper researches the use of log files generated by NetFlow version 9 and IPFIX to identify successful and unsuccessful exploit attacks commonly used by automated systems. These malicious communications include but are not limited to exploits that attack Microsoft RPC, Samba, NTP (Network Time Protocol) and IRC (Internet Relay Chat). These attacks are recreated through existing exploit implementations on Metasploit and through hand-crafted reconstructions of exploits via known documentation of vulnerabilities. These attacks are then monitored through a preconfigured virtual testbed containing gateways and network connections commonly found on the Internet. This common attack identification system is intended for insertion as a parallel module for Bolvedere in order to further the increase the Bolvedere system's attack detection capability.
- Full Text:
Adaptations in allopatric populations of Triakis megalopterus isolated by the Benguela Current: steps towards understanding evolutionary processes affecting regional biodiversity
- Authors: Soekoe, Michelle
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5389 , http://hdl.handle.net/10962/d1021264
- Description: This study was initiated to gain a better understanding of evolution and adaptation of elasmobranchs by investigating how a putative biogeographic barrier, the Benguela Current, had influenced populations of a demersal shark species, Triakis megalopterus. It was hypothesized that the Benguela Current formed a biogeographic barrier in the distribution of T. megalopterus and was responsible for the divergence between South African (SA) and Angolan (AN) populations. Since elasmobranchs are generally characterized by a slow rate of evolutionary change and conservative morphology and life history traits, it was hypothesized that there would be limited genetic, morphological and life history divergence between the populations. Both mtDNA Control Region (mtCR) and microsatellites (nDNA) were used to assess population connectivity and structure of T. megalopterus. The mtCR predominantly showed a northern (Angola, AN, and Namibia, NA) versus southern (Western Cape, WC, and Eastern Cape, EC) Benguela subsystem arrangement. This suggested that the formation of the Benguela Current had an influence on the genetic structure of T. megalopterus during the early Pleistocene. The nDNA, however, showed a distinct transoceanic, Atlantic (AN, NA, WC) versus Indian Ocean (EC) arrangement, and this was attributed to the more recent exposure of the Agulhas Bank and reduced rocky shore habitat during the glaciations of the late Pleistocene. Traditional morphological analyses on full body and tooth morphology were used to assess phenotypic plasticity and/or adaptability of T. megalopterus. A novel method of geometric morphology, with potential for non-lethal application, was developed and tested to examine interpopulation divergence in shape. Traditional morphometrics showed significant divergence between populations and this variation was congruous with the mtCR haplotypes. However, the divergence in the truss variables was not concomitant to the haplotypes and suggested that differences in shape may be attributed to phenotypic plasticity. There was limited divergence in the tooth morphology between populations. The divergence in several morphological characters associated with swimming speed and manoeuvrability may be attributed to both habitat structure and dominant prey in the different biogeographic zones. The diet of T. megalopterus consisted primarily of crustaceans, teleosts and molluscs. The significant variation in the diet between populations suggested a generalist tooth configuration and broad trophic adaptability. There was significant divergence in the interpopulation life history parameters. The AN population had the fastest growth, smallest size at maturity, and shortest longevity. Individuals in the EC population had the youngest age at maturity, while the WC population had the earliest parturition. This divergence may be attributed to the contrasting thermal regimes in the three biogeographic regions and the dissimilar exploitation rates of the three populations. The results of this thesis demonstrated that a combination of the formation of the Benguela Current and sea level change most likely contributed to vicariance of three populations of T. megalopterus. The significant interpopulation morphological and life history divergence appeared to be both phenotypic and genetic, and suggested that contrasting environmental drivers can result in relatively rapid change in elasmobranchs.
- Full Text:
- Authors: Soekoe, Michelle
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5389 , http://hdl.handle.net/10962/d1021264
- Description: This study was initiated to gain a better understanding of evolution and adaptation of elasmobranchs by investigating how a putative biogeographic barrier, the Benguela Current, had influenced populations of a demersal shark species, Triakis megalopterus. It was hypothesized that the Benguela Current formed a biogeographic barrier in the distribution of T. megalopterus and was responsible for the divergence between South African (SA) and Angolan (AN) populations. Since elasmobranchs are generally characterized by a slow rate of evolutionary change and conservative morphology and life history traits, it was hypothesized that there would be limited genetic, morphological and life history divergence between the populations. Both mtDNA Control Region (mtCR) and microsatellites (nDNA) were used to assess population connectivity and structure of T. megalopterus. The mtCR predominantly showed a northern (Angola, AN, and Namibia, NA) versus southern (Western Cape, WC, and Eastern Cape, EC) Benguela subsystem arrangement. This suggested that the formation of the Benguela Current had an influence on the genetic structure of T. megalopterus during the early Pleistocene. The nDNA, however, showed a distinct transoceanic, Atlantic (AN, NA, WC) versus Indian Ocean (EC) arrangement, and this was attributed to the more recent exposure of the Agulhas Bank and reduced rocky shore habitat during the glaciations of the late Pleistocene. Traditional morphological analyses on full body and tooth morphology were used to assess phenotypic plasticity and/or adaptability of T. megalopterus. A novel method of geometric morphology, with potential for non-lethal application, was developed and tested to examine interpopulation divergence in shape. Traditional morphometrics showed significant divergence between populations and this variation was congruous with the mtCR haplotypes. However, the divergence in the truss variables was not concomitant to the haplotypes and suggested that differences in shape may be attributed to phenotypic plasticity. There was limited divergence in the tooth morphology between populations. The divergence in several morphological characters associated with swimming speed and manoeuvrability may be attributed to both habitat structure and dominant prey in the different biogeographic zones. The diet of T. megalopterus consisted primarily of crustaceans, teleosts and molluscs. The significant variation in the diet between populations suggested a generalist tooth configuration and broad trophic adaptability. There was significant divergence in the interpopulation life history parameters. The AN population had the fastest growth, smallest size at maturity, and shortest longevity. Individuals in the EC population had the youngest age at maturity, while the WC population had the earliest parturition. This divergence may be attributed to the contrasting thermal regimes in the three biogeographic regions and the dissimilar exploitation rates of the three populations. The results of this thesis demonstrated that a combination of the formation of the Benguela Current and sea level change most likely contributed to vicariance of three populations of T. megalopterus. The significant interpopulation morphological and life history divergence appeared to be both phenotypic and genetic, and suggested that contrasting environmental drivers can result in relatively rapid change in elasmobranchs.
- Full Text:
Administrative penalties
- Arendse, Jacqueline A, Clegg, David, Williams, Robert C
- Authors: Arendse, Jacqueline A , Clegg, David , Williams, Robert C
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/131225 , vital:36539 , https://store.lexisnexis.co.za/products/silke-on-tax-administration-skuZASKUPG1440
- Description: Provisions dealing with the levying of interest and penalties are contained in the Tax Administration Act and specific provisions also exist in the various tax Acts. Most of the specific penalty provisions in the various tax Acts have been replaced by the general provisions contained in the Tax Administration Act.
- Full Text: false
- Authors: Arendse, Jacqueline A , Clegg, David , Williams, Robert C
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/131225 , vital:36539 , https://store.lexisnexis.co.za/products/silke-on-tax-administration-skuZASKUPG1440
- Description: Provisions dealing with the levying of interest and penalties are contained in the Tax Administration Act and specific provisions also exist in the various tax Acts. Most of the specific penalty provisions in the various tax Acts have been replaced by the general provisions contained in the Tax Administration Act.
- Full Text: false
Advance rulings
- Arendse, Jacqueline A, Clegg, David, Williams, Robert C
- Authors: Arendse, Jacqueline A , Clegg, David , Williams, Robert C
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/131195 , vital:36535 , https://store.lexisnexis.co.za/products/silke-on-tax-administration-skuZASKUPG1440
- Description: Chapter 7 of the Tax Administration Act, namely ss 75–90, deals with the formal system and process of the advance tax ruling system. It therefore follows that SARS may now issue advance rulings in respect of all tax types and tax Acts administered by the Commissioner. Procedures and guidelines, in the form of ‘binding general rulings’, for implementation and operation of the ‘advance ruling’ system may be issued by the Commissioner to give effect to the advance tax ruling system.
- Full Text: false
- Authors: Arendse, Jacqueline A , Clegg, David , Williams, Robert C
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/131195 , vital:36535 , https://store.lexisnexis.co.za/products/silke-on-tax-administration-skuZASKUPG1440
- Description: Chapter 7 of the Tax Administration Act, namely ss 75–90, deals with the formal system and process of the advance tax ruling system. It therefore follows that SARS may now issue advance rulings in respect of all tax types and tax Acts administered by the Commissioner. Procedures and guidelines, in the form of ‘binding general rulings’, for implementation and operation of the ‘advance ruling’ system may be issued by the Commissioner to give effect to the advance tax ruling system.
- Full Text: false
Age and growth of Cape stumpnose Rhabdosargus holubi (Pisces: Sparidae) in the Eastern Cape, South Africa
- Farthing, Matthew William, James, Nicola C, Potts, Warren M
- Authors: Farthing, Matthew William , James, Nicola C , Potts, Warren M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/122891 , vital:35365 , https://doi.org/10.2989/1814232X.2016.1156577
- Description: Rhabdosargus holubi (Steindachner, 1881) is a small (maximum size = 450 mm total length; Heemstra and Heemstra 2004) sparid that is distributed along the south-east coast of Africa from St Helena Bay, South Africa, to Maputo, Mozambique (Götz and Cowley 2013). Spawning occurs in the nearshore marine environment primarily during winter, specifically May–August in KwaZulu-Natal (KZN) (Wallace 1975) and July–February in the South-Eastern Cape (Whitfield 1998). Individuals reach 50% sexual maturity at approximately 150 mm standard length (SL) in the Eastern Cape (Whitfield 1998). The early life stages are transported by the south-westward-flowing Agulhas Current, and recruit as post-flexion larvae and early juveniles into estuaries during late winter and early summer (Blaber 1974). The warm temperatures and high nutrient levels in estuaries favour fast growth (Blaber 1973a), and fish spend their first year of life in these environments, migrating back out to sea after reaching approximately 120 mm SL. Some individuals remain trapped in closed estuaries, where they may reach sizes greater than 200 mm SL (James et al. 2007a). Rhabdosargus holubi is the dominant estuarine-dependent marine teleost species recorded in permanently open and temporarily open/closed estuaries in the warm-temperate region, which spans the south, south-east and east coast of South Africa (Harrison 2005). The species is also an important component of the linefishery in many SouthAfrican estuaries (10–15.6% by number) (Pradervand and Baird 2002), particularly in Eastern Cape estuaries (Cowley et al. 2003). These figures underestimate the presence of R. holubi, as most individuals making use of estuaries are young, feeding predominately on filamentous macroalgae and diatom flora, and are generally too small to be caught with hook and line (De Wet and Marais 1990). James et al. (2007b) showed that R. holubi made up 34–92% of the annual seine-net catch in the East Kleinemonde Estuary. Rhabdosargus holubi is also important in the KZN shorebased linefishery, representing 4.6% of the total landed catch (Dunlop and Mann 2012).
- Full Text:
- Authors: Farthing, Matthew William , James, Nicola C , Potts, Warren M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/122891 , vital:35365 , https://doi.org/10.2989/1814232X.2016.1156577
- Description: Rhabdosargus holubi (Steindachner, 1881) is a small (maximum size = 450 mm total length; Heemstra and Heemstra 2004) sparid that is distributed along the south-east coast of Africa from St Helena Bay, South Africa, to Maputo, Mozambique (Götz and Cowley 2013). Spawning occurs in the nearshore marine environment primarily during winter, specifically May–August in KwaZulu-Natal (KZN) (Wallace 1975) and July–February in the South-Eastern Cape (Whitfield 1998). Individuals reach 50% sexual maturity at approximately 150 mm standard length (SL) in the Eastern Cape (Whitfield 1998). The early life stages are transported by the south-westward-flowing Agulhas Current, and recruit as post-flexion larvae and early juveniles into estuaries during late winter and early summer (Blaber 1974). The warm temperatures and high nutrient levels in estuaries favour fast growth (Blaber 1973a), and fish spend their first year of life in these environments, migrating back out to sea after reaching approximately 120 mm SL. Some individuals remain trapped in closed estuaries, where they may reach sizes greater than 200 mm SL (James et al. 2007a). Rhabdosargus holubi is the dominant estuarine-dependent marine teleost species recorded in permanently open and temporarily open/closed estuaries in the warm-temperate region, which spans the south, south-east and east coast of South Africa (Harrison 2005). The species is also an important component of the linefishery in many SouthAfrican estuaries (10–15.6% by number) (Pradervand and Baird 2002), particularly in Eastern Cape estuaries (Cowley et al. 2003). These figures underestimate the presence of R. holubi, as most individuals making use of estuaries are young, feeding predominately on filamentous macroalgae and diatom flora, and are generally too small to be caught with hook and line (De Wet and Marais 1990). James et al. (2007b) showed that R. holubi made up 34–92% of the annual seine-net catch in the East Kleinemonde Estuary. Rhabdosargus holubi is also important in the KZN shorebased linefishery, representing 4.6% of the total landed catch (Dunlop and Mann 2012).
- Full Text:
Agentive learning for sustainability and equity: Communities, cooperatives and social movements as emerging foci of the learning sciences
- Engeström, Yrjö, Sannino, Annalisa, Bal, Aydin, Lotz-Sisitka, Heila, Pesanayi, Tichaona, Chikunda, Charles, Lesama, Manoel F, Picinatto, Antonio C, Querol, Marco P, Lee, Yew J
- Authors: Engeström, Yrjö , Sannino, Annalisa , Bal, Aydin , Lotz-Sisitka, Heila , Pesanayi, Tichaona , Chikunda, Charles , Lesama, Manoel F , Picinatto, Antonio C , Querol, Marco P , Lee, Yew J
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , symposium
- Identifier: http://hdl.handle.net/10962/436670 , vital:73292 , ISBN 978-1-4312-0852-4 , https://repository.isls.org//handle/1/372
- Description: This symposium expands the object and scope of the learning sciences by introducing communities, cooperatives and social movements as crucially important sites of learning. The sym-posium papers employ and critically interrogate cultural-historical activity theory, specifically the theory of expansive learning, and the emerging methodology of formative interven-tions as a potential framework for dealing with learning in communities, cooperatives and social movements. Expansive learning emerges as a process of revitalizing the commons, or commoning. The contributions of the symposium point toward the importance of analyzing and fostering transformative agency as a quality of learning.
- Full Text:
- Authors: Engeström, Yrjö , Sannino, Annalisa , Bal, Aydin , Lotz-Sisitka, Heila , Pesanayi, Tichaona , Chikunda, Charles , Lesama, Manoel F , Picinatto, Antonio C , Querol, Marco P , Lee, Yew J
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , symposium
- Identifier: http://hdl.handle.net/10962/436670 , vital:73292 , ISBN 978-1-4312-0852-4 , https://repository.isls.org//handle/1/372
- Description: This symposium expands the object and scope of the learning sciences by introducing communities, cooperatives and social movements as crucially important sites of learning. The sym-posium papers employ and critically interrogate cultural-historical activity theory, specifically the theory of expansive learning, and the emerging methodology of formative interven-tions as a potential framework for dealing with learning in communities, cooperatives and social movements. Expansive learning emerges as a process of revitalizing the commons, or commoning. The contributions of the symposium point toward the importance of analyzing and fostering transformative agency as a quality of learning.
- Full Text:
Aggregation control of robust water-soluble zinc (II) phthalocyanine-based photosensitizers
- Ikeuchi, Takuro, Mack, John, Nyokong, Tebello, Kobayashi, Nagao, Kimura, Mutsumi
- Authors: Ikeuchi, Takuro , Mack, John , Nyokong, Tebello , Kobayashi, Nagao , Kimura, Mutsumi
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239709 , vital:50757 , xlink:href="https://doi.org/10.1021/acs.langmuir.6b03552"
- Description: A water-soluble zinc phthalocyanine (ZnPc) complex with four negatively charged electron-withdrawing sulfonic acid substituents at the nonperipheral positions (α-ZnTSPc) is found to have a high singlet oxygen (1O2) quantum yield and exhibits high photostability. The formation of aggregates is hindered and the highest occupied molecular orbital is significantly stabilized, making α-ZnTSPc potentially suitable for its use as a photosensitizer for photodynamic therapy and photoimmunotherapy. Atomic force microscopy (AFM) reveals that mixtures of the negatively charged α-ZnTSPc complex with a similar positively charged ZnPc were found to result in the self-assembly of one-dimensional accordion-like fibers. Supramolecular fibers can be formed in aqueous solutions through intermolecular electrostatic and donor–acceptor interactions between the two water-soluble ZnPcs.
- Full Text:
- Authors: Ikeuchi, Takuro , Mack, John , Nyokong, Tebello , Kobayashi, Nagao , Kimura, Mutsumi
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239709 , vital:50757 , xlink:href="https://doi.org/10.1021/acs.langmuir.6b03552"
- Description: A water-soluble zinc phthalocyanine (ZnPc) complex with four negatively charged electron-withdrawing sulfonic acid substituents at the nonperipheral positions (α-ZnTSPc) is found to have a high singlet oxygen (1O2) quantum yield and exhibits high photostability. The formation of aggregates is hindered and the highest occupied molecular orbital is significantly stabilized, making α-ZnTSPc potentially suitable for its use as a photosensitizer for photodynamic therapy and photoimmunotherapy. Atomic force microscopy (AFM) reveals that mixtures of the negatively charged α-ZnTSPc complex with a similar positively charged ZnPc were found to result in the self-assembly of one-dimensional accordion-like fibers. Supramolecular fibers can be formed in aqueous solutions through intermolecular electrostatic and donor–acceptor interactions between the two water-soluble ZnPcs.
- Full Text:
Agreement and coordination in XiTsonga, SeSotho and IsiXhosa: an optimality theoretic perspective
- Authors: Mitchley, Hazel
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3423 , vital:20491
- Description: This thesis provides a unified Optimality Theoretic analysis of subject-verb agreement with coordinated preverbal subjects in three Southern Bantu languages: Xitsonga (S53), Sesotho (S33), and isiXhosa (S41). This analysis is then used to formulate a typology of agreement resolution strategies and the contexts which trigger them. Although some accounts in the Bantu literature suggest that agreement with coordinate structures is avoided by speakers (e.g. Schadeberg 1992, Voeltz 1971) especially when conjuncts are from different noun classes, I show that there is ample evidence to the contrary, and that the subject marker used is dependent on several factors, including (i) the [-HUMAN] specification on the conjuncts, (ii) whether the conjuncts are singular or plural, (iii) whether or not the conjuncts both carry the same noun class feature, and (iv) the order of the conjuncts. This thesis shows that there are various agreement resolution strategies which can beused: 1) agreement with the [+HUMAN] feature on the conjuncts, 2) agreement with the[-HUMAN] feature on the conjuncts, 3) agreement with the noun class feature on both conjuncts, 4) agreement with the noun class feature on the conjunct closest to the verb, and 5) agreement with the noun class feature on the conjunct furthest from the verb. Not all of these strategies are used by all languages, nor are these strategies interchangeable in the languages which do use them – instead, multiple factors conspire to trigger the use of a specific agreement strategy within a specific agreement featural context. I show that these effects can be captured using Optimality Theory (Prince and Smolensky 2004). The analysis makes use of seven constraints: RES#, MAX[+H], MAX[-H], DEP[-H], MAXNC, DEPNC, and AGREECLOSEST. The hierarchical ranking of these constraints not only accounts for the confinement of particular strategies to specific agreement featural contexts within a language, but also accounts for the cross-linguistic differences in the use of these strategies. I end off by examining the typological implications which follow from the OT analysis provided in this thesis.
- Full Text:
- Authors: Mitchley, Hazel
- Date: 2016
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/3423 , vital:20491
- Description: This thesis provides a unified Optimality Theoretic analysis of subject-verb agreement with coordinated preverbal subjects in three Southern Bantu languages: Xitsonga (S53), Sesotho (S33), and isiXhosa (S41). This analysis is then used to formulate a typology of agreement resolution strategies and the contexts which trigger them. Although some accounts in the Bantu literature suggest that agreement with coordinate structures is avoided by speakers (e.g. Schadeberg 1992, Voeltz 1971) especially when conjuncts are from different noun classes, I show that there is ample evidence to the contrary, and that the subject marker used is dependent on several factors, including (i) the [-HUMAN] specification on the conjuncts, (ii) whether the conjuncts are singular or plural, (iii) whether or not the conjuncts both carry the same noun class feature, and (iv) the order of the conjuncts. This thesis shows that there are various agreement resolution strategies which can beused: 1) agreement with the [+HUMAN] feature on the conjuncts, 2) agreement with the[-HUMAN] feature on the conjuncts, 3) agreement with the noun class feature on both conjuncts, 4) agreement with the noun class feature on the conjunct closest to the verb, and 5) agreement with the noun class feature on the conjunct furthest from the verb. Not all of these strategies are used by all languages, nor are these strategies interchangeable in the languages which do use them – instead, multiple factors conspire to trigger the use of a specific agreement strategy within a specific agreement featural context. I show that these effects can be captured using Optimality Theory (Prince and Smolensky 2004). The analysis makes use of seven constraints: RES#, MAX[+H], MAX[-H], DEP[-H], MAXNC, DEPNC, and AGREECLOSEST. The hierarchical ranking of these constraints not only accounts for the confinement of particular strategies to specific agreement featural contexts within a language, but also accounts for the cross-linguistic differences in the use of these strategies. I end off by examining the typological implications which follow from the OT analysis provided in this thesis.
- Full Text:
Allelopathic effects of Lantana camara on indigenous forest species in South Africa
- Ruwanza, Sheunesu, Shackleton, Charlie M
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
- Full Text:
- Authors: Ruwanza, Sheunesu , Shackleton, Charlie M
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182296 , vital:43818 , xlink:href="http://www.allelopathyjournal.org/?"
- Description: Lantana camara, is an invasive plant in South Africa and greatly influences the forest spp. In greenhouse, we evaluated the allelopathic effects of aqueous extracts of L. camara leaf, stem and root on 5-test species, (3-forest species viz., Acacia natalitia, Kiggalaria africana and Searsia crenata and 2-crops: Solanum lycopersicum and Lactuca sativa). Potential allelopathic compounds present in L. camara leaf, stem and root aqueous extracts were identified using gas chromatography mass spectrometry (GC-MS). The leaf, stem and root aqueous extracts of L. camara reduced the seed germination and seedling growth of all test species showing that L. camara aqueous extracts were deleterious to all test species. We identified 92 major volatile organic components in L. camara aqueous extracts. These compounds had the potential to inhibit the germination and seedling growth of test crops. The leaf, stem and root aqueous extracts of L. camara contained the allelopathic compounds that inhibited the germination and seedling growth of indigenous forest species and crop species.
- Full Text:
Allopatric speciation in the flightless Phoberus capensis (Coleoptera: Trogidae) group, with description of two new species
- Strümpher, Werner P, Sole, Catherine L, Villet, Martin H, Scholtz, Clarke H
- Authors: Strümpher, Werner P , Sole, Catherine L , Villet, Martin H , Scholtz, Clarke H
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/442730 , vital:74028 , ISBN , https://brill.com/view/journals/ise/47/2/article-p149_4.xml
- Description: The name Phoberus capensis (Scholtz) is applied to a small flightless, keratinophagous beetle endemic to the Cape Floristic Region of South Africa. Its gross distribution stretches from roughly 1000 km from the Cederberg (32°24’22” S, 19°04’50” E) to Grahamstown (33°20’07” S, 26°32’50” E). The populations are spatially discrete, restricted to relict forests of the southern Cape and disjunct high montane refugia of the Cape Fold Mountains. We test the hypothesis that there is more than one distinct species nested within the name P . capensis . Phylogenetic relationships among populations were inferred using molecular sequence data. The results support three distinct evolutionary lineages, which were also supported by morphological characters. Divergence time estimates suggest Pliocene-Pleistocene diversification. Based on these results, it is suggested that the P. capensis lineage experienced climatically-driven allopatric speciation with sheltered Afrotemperate forests and high mountain peaks serving as important refugia in response to climatic ameliorations. The P. capensis complex thus represents a speciation process in which flight-restricted populations evolved in close allopatry, possibly as recently as the Pleistocene. Two divergent and geographically distinct lineages are described as novel species: The new species, P . disjunctus sp. n. and P . herminae sp. n., are illustrated by photographs of habitus and male aedeagi.
- Full Text:
- Authors: Strümpher, Werner P , Sole, Catherine L , Villet, Martin H , Scholtz, Clarke H
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/442730 , vital:74028 , ISBN , https://brill.com/view/journals/ise/47/2/article-p149_4.xml
- Description: The name Phoberus capensis (Scholtz) is applied to a small flightless, keratinophagous beetle endemic to the Cape Floristic Region of South Africa. Its gross distribution stretches from roughly 1000 km from the Cederberg (32°24’22” S, 19°04’50” E) to Grahamstown (33°20’07” S, 26°32’50” E). The populations are spatially discrete, restricted to relict forests of the southern Cape and disjunct high montane refugia of the Cape Fold Mountains. We test the hypothesis that there is more than one distinct species nested within the name P . capensis . Phylogenetic relationships among populations were inferred using molecular sequence data. The results support three distinct evolutionary lineages, which were also supported by morphological characters. Divergence time estimates suggest Pliocene-Pleistocene diversification. Based on these results, it is suggested that the P. capensis lineage experienced climatically-driven allopatric speciation with sheltered Afrotemperate forests and high mountain peaks serving as important refugia in response to climatic ameliorations. The P. capensis complex thus represents a speciation process in which flight-restricted populations evolved in close allopatry, possibly as recently as the Pleistocene. Two divergent and geographically distinct lineages are described as novel species: The new species, P . disjunctus sp. n. and P . herminae sp. n., are illustrated by photographs of habitus and male aedeagi.
- Full Text:
Alzheimer’s disease: making sense of the stress
- Authors: Whiteley, Chris G
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67072 , vital:29029 , http://www.smgebooks.com/alzheimers-disease/chapters/ALZD-16-08.pdf
- Description: publisher version , To facilitate a deep understanding of the mechanisms involved in neurodegeneration and Alzheimer’s disease fundamental knowledge is required about the action and function of enzymes in the brain that not only metabolise arginine (neuronal nitric oxide synthase) but are closely associated with oxidative (superoxide dismutase; catalase; glutathione peroxidase) and/or nitrosative stress. In particular the focus extends towards enzymes that contribute to amyloid peptide aggregation and senile plaquedeposits (fibrillogenesis). Of special importance are the glycine zipper regions within these amyloid peptides, especially Aβ25-29 and Aβ29-33 (that contains two isoleucine residues) and the pentapeptide Aβ17-21 (that contains two phenylalanines), each generated by enzymatic cleavage of the intramembrane amyloid precursor protein. Use of antisense-sense technology has identified regions in each enzyme that are capable of binding with the amyloid peptides. After an initial inhibition of each enzyme there is an oligomerisation into soluble fibrils which accumulate and eventually precipitate. The use of nanoparticles do not just prevent but reverse the formation of these fibrils either by disrupting the binary adduct – enzyme-Aβ-peptide- or by reaction with, and therefore deplete, Aβ-monomers in solution and so block potential aggregation sites on the enzyme itself. Future therapy towards Alzheimer’s disease should target the C-terminal region of the amyloid precursor protein and substitute hydrophobic residues for the glycine amino acids within the glycine zipper region.
- Full Text:
- Authors: Whiteley, Chris G
- Date: 2016
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67072 , vital:29029 , http://www.smgebooks.com/alzheimers-disease/chapters/ALZD-16-08.pdf
- Description: publisher version , To facilitate a deep understanding of the mechanisms involved in neurodegeneration and Alzheimer’s disease fundamental knowledge is required about the action and function of enzymes in the brain that not only metabolise arginine (neuronal nitric oxide synthase) but are closely associated with oxidative (superoxide dismutase; catalase; glutathione peroxidase) and/or nitrosative stress. In particular the focus extends towards enzymes that contribute to amyloid peptide aggregation and senile plaquedeposits (fibrillogenesis). Of special importance are the glycine zipper regions within these amyloid peptides, especially Aβ25-29 and Aβ29-33 (that contains two isoleucine residues) and the pentapeptide Aβ17-21 (that contains two phenylalanines), each generated by enzymatic cleavage of the intramembrane amyloid precursor protein. Use of antisense-sense technology has identified regions in each enzyme that are capable of binding with the amyloid peptides. After an initial inhibition of each enzyme there is an oligomerisation into soluble fibrils which accumulate and eventually precipitate. The use of nanoparticles do not just prevent but reverse the formation of these fibrils either by disrupting the binary adduct – enzyme-Aβ-peptide- or by reaction with, and therefore deplete, Aβ-monomers in solution and so block potential aggregation sites on the enzyme itself. Future therapy towards Alzheimer’s disease should target the C-terminal region of the amyloid precursor protein and substitute hydrophobic residues for the glycine amino acids within the glycine zipper region.
- Full Text:
An analysis of how students construct knowledge in a course with a hierarchical knowledge structure
- Authors: Myers, Peta L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66995 , vital:29014 , https://doi.org/10.1080/10291954.2016.1196528
- Description: publisher version , Passing the introductory accounting semester is often seen as a challenge for first year students. Being aware of both effective and ineffective ways of constructing knowledge in a discipline with a hierarchical knowledge structure will be of value to students and teachers alike in assisting in the development of effective styles of learning. This article, which is part of a larger body of research, analyses how students in an introductory financial accounting class at Rhodes University constructed knowledge. Previous research described the course as having a hierarchical knowledge structure. In this research, first year accounting students at Rhodes University were interviewed to gain an improved understanding of how they constructed knowledge in this course. This article describes how students who were successful in passing this semester course used similar, effective ways of constructing knowledge, while students who were not successful also employed similar but less effective ways of constructing knowledge. These different ways of constructing knowledge, both effective and ineffective, were analysed, using the Bernstein’s pedagogic device and Maton’s Legitimation Code Theory. This article provides those involved in teaching and learning in a discipline with a hierarchical knowledge structure, with a theoretical explanation of why some methods of constructing knowledge are more effective than others. Understanding and being explicit about more (and less) effective ways of constructing knowledge in a course with a hierarchical knowledge structure can guide those involved in teaching and learning to improve results.
- Full Text: false
- Authors: Myers, Peta L
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66995 , vital:29014 , https://doi.org/10.1080/10291954.2016.1196528
- Description: publisher version , Passing the introductory accounting semester is often seen as a challenge for first year students. Being aware of both effective and ineffective ways of constructing knowledge in a discipline with a hierarchical knowledge structure will be of value to students and teachers alike in assisting in the development of effective styles of learning. This article, which is part of a larger body of research, analyses how students in an introductory financial accounting class at Rhodes University constructed knowledge. Previous research described the course as having a hierarchical knowledge structure. In this research, first year accounting students at Rhodes University were interviewed to gain an improved understanding of how they constructed knowledge in this course. This article describes how students who were successful in passing this semester course used similar, effective ways of constructing knowledge, while students who were not successful also employed similar but less effective ways of constructing knowledge. These different ways of constructing knowledge, both effective and ineffective, were analysed, using the Bernstein’s pedagogic device and Maton’s Legitimation Code Theory. This article provides those involved in teaching and learning in a discipline with a hierarchical knowledge structure, with a theoretical explanation of why some methods of constructing knowledge are more effective than others. Understanding and being explicit about more (and less) effective ways of constructing knowledge in a course with a hierarchical knowledge structure can guide those involved in teaching and learning to improve results.
- Full Text: false