Data classification for artificial intelligence construct training to aid in network incident identification using network telescope data
- Cowie, Bradley, Irwin, Barry V W
- Authors: Cowie, Bradley , Irwin, Barry V W
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430125 , vital:72667 , https://doi.org/10.1145/1899503.1899544
- Description: This paper considers the complexities involved in obtaining training da-ta for use by artificial intelligence constructs to identify potential network incidents using passive network telescope data. While a large amount of data obtained from network telescopes exists, this data is not current-ly marked for known incidents. Problems related to this marking process include the accuracy of the markings, the validity of the original data and the time involved. In an attempt to solve these issues two methods of training data generation are considered namely; manual identification and automated generation. The manual technique considers heuristics for finding network incidents while the automated technique considers building simulated data sets using existing models of virus propagation and malicious activity. An example artificial intelligence system is then constructed using these marked datasets.
- Full Text:
- Date Issued: 2010
- Authors: Cowie, Bradley , Irwin, Barry V W
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430125 , vital:72667 , https://doi.org/10.1145/1899503.1899544
- Description: This paper considers the complexities involved in obtaining training da-ta for use by artificial intelligence constructs to identify potential network incidents using passive network telescope data. While a large amount of data obtained from network telescopes exists, this data is not current-ly marked for known incidents. Problems related to this marking process include the accuracy of the markings, the validity of the original data and the time involved. In an attempt to solve these issues two methods of training data generation are considered namely; manual identification and automated generation. The manual technique considers heuristics for finding network incidents while the automated technique considers building simulated data sets using existing models of virus propagation and malicious activity. An example artificial intelligence system is then constructed using these marked datasets.
- Full Text:
- Date Issued: 2010
David Lurie's learning and the meaning of J.M. Coetzee's Disgrace
- Authors: Wright, Laurence
- Date: 2010
- Language: English
- Type: text , article
- Identifier: vital:7063 , http://hdl.handle.net/10962/d1007428 , http://hdl.handle.net/10520/EJC47864
- Description: preprint , One of the teasing characteristics of novels soused in literariness, like J.M. Coetzee’s, is their tendency to leak, to bleed, into vast inchoate terrains of intertextuality.The reader is constantly challenged to measure and assess their implications within or against the frail containing form of the story, much as Russian formalism taught us to keep sujet and fable in perpetual dialogue. However, it has become apparent that in the dense thickets of commentary occasioned by Coetzee’s most controversial novel, Disgrace (1999), insufficient attention has been paid to the intertextual implications of David Lurie’s learning, his scholarly preoccupations. Unless the reader attempts this kind of exploration, two of the most vexed issues freighting the novel’s central fabulation: Lucy’s curiously stoical, impassive response to her rape, together with her decision to stay on in South Africa; and David Lurie’s sudden, seemingly inexplicable care for the doomed dogs, from their last moments at the animal shelter until he lovingly consigns their corpses to the incinerator, must remain opaque. In particular, the final words of the novel, “Yes, I am giving him up” (220), uttered in relation to the immanent “Lösung” of the little dog Bev Shaw calls Driepoot, will tend to taunt the reader, rather than illuminate.
- Full Text:
- Date Issued: 2010
- Authors: Wright, Laurence
- Date: 2010
- Language: English
- Type: text , article
- Identifier: vital:7063 , http://hdl.handle.net/10962/d1007428 , http://hdl.handle.net/10520/EJC47864
- Description: preprint , One of the teasing characteristics of novels soused in literariness, like J.M. Coetzee’s, is their tendency to leak, to bleed, into vast inchoate terrains of intertextuality.The reader is constantly challenged to measure and assess their implications within or against the frail containing form of the story, much as Russian formalism taught us to keep sujet and fable in perpetual dialogue. However, it has become apparent that in the dense thickets of commentary occasioned by Coetzee’s most controversial novel, Disgrace (1999), insufficient attention has been paid to the intertextual implications of David Lurie’s learning, his scholarly preoccupations. Unless the reader attempts this kind of exploration, two of the most vexed issues freighting the novel’s central fabulation: Lucy’s curiously stoical, impassive response to her rape, together with her decision to stay on in South Africa; and David Lurie’s sudden, seemingly inexplicable care for the doomed dogs, from their last moments at the animal shelter until he lovingly consigns their corpses to the incinerator, must remain opaque. In particular, the final words of the novel, “Yes, I am giving him up” (220), uttered in relation to the immanent “Lösung” of the little dog Bev Shaw calls Driepoot, will tend to taunt the reader, rather than illuminate.
- Full Text:
- Date Issued: 2010
Day-of-the-week effect : evidence from nine sectors of the South African stock market
- Authors: Mbululu, Douglas
- Date: 2010
- Subjects: Stock exchanges -- South Africa , Johannesburg Stock Exchange , Stocks -- Prices -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1024 , http://hdl.handle.net/10962/d1002759 , Stock exchanges -- South Africa , Johannesburg Stock Exchange , Stocks -- Prices -- South Africa
- Description: The day-of-the-week effect in share prices is one of the most extensively researched anomalies, especially in developed markets. However, emerging African stock markets have received little attention in this regard. This study breaks new ground in using non-parametric tests directly on skewness and kurtosis to examine whether the day-of-he-week effect exists in nine listed stock market sector indices of the JSE Securities Exchange of South Africa (JSE). Different day-of-the-week effects were found to be present in the statistical moments of returns of these nine JSE sectors
- Full Text:
- Date Issued: 2010
- Authors: Mbululu, Douglas
- Date: 2010
- Subjects: Stock exchanges -- South Africa , Johannesburg Stock Exchange , Stocks -- Prices -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1024 , http://hdl.handle.net/10962/d1002759 , Stock exchanges -- South Africa , Johannesburg Stock Exchange , Stocks -- Prices -- South Africa
- Description: The day-of-the-week effect in share prices is one of the most extensively researched anomalies, especially in developed markets. However, emerging African stock markets have received little attention in this regard. This study breaks new ground in using non-parametric tests directly on skewness and kurtosis to examine whether the day-of-he-week effect exists in nine listed stock market sector indices of the JSE Securities Exchange of South Africa (JSE). Different day-of-the-week effects were found to be present in the statistical moments of returns of these nine JSE sectors
- Full Text:
- Date Issued: 2010
Deliberating the Dialogues: a critical examination of the nature and purpose of a Daily Dispatch public journalism project
- Authors: Amner, Roderick John
- Date: 2010
- Subjects: Daily Dispatch (East London, South Africa) Journalism -- South Africa -- East London Citizen journalism -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3417 , http://hdl.handle.net/10962/d1002870
- Description: This thesis critically examines the nature and purpose of a series of four town-hall-like meetings, the Community Dialogues, held in the townships and suburbs of East London, South Africa, in 2009. They were undertaken by a mainstream, commercial newspaper, the Daily Dispatch, under the banner of the worldwide public journalism movement. Following Christians et al (2009), the thesis sets out a normative framework of media performance in a democracy, including a detailed and critical normative theory of the ‘facilitative role’ proposed and developed by Haas (2007), one of the public journalism movement’s key advocate-theorists. It also draws on a variety of theoretical frameworks and perspectives in the fields of Political Studies and Media Studies to provide an analytical overview of the complex matrix of political and media contexts – at the macro (global), meso (national) and micro (local) levels – that have helped give impetus to the Community Dialogues and also shaped their ongoing operation as a public journalism strategy in the South African context. Following a critical realist case study design, the thesis goes on to provide a narrative account of the Dialogues based on in-depth interviews exploring the motivations, self-understandings and perceptions of those journalists who originated, directed and participated in this project, as well as observation of a Community Dialogue, and an examination of some of the journalistic texts related to the Dialogues. This primary data is then critically evaluated against normative theories of press performance, especially Haas’s ‘public philosophy’ of public journalism. The thesis found that apart from their undoubted success in generating a more comprehensive and representative news agenda for the newspaper, the Dialogues often fell short of Habermas’s (1989) proceduralist-discursive notion of the ‘deliberating public’, which sees citizens share a commitment to engage in common deliberation and public problem solving. This can be attributed to a number of problems, including some important theoretical/conceptual weaknesses in the Community Dialogues’ project design, the relative immaturity of the project, the domination of civil society by political society in the South African political context, and a number of organisational constraints at the Daily Dispatch. On the other hand, the newspaper’s editorial leadership has shown clear commitment to the idea of expanding the project in the future, establishing a more a more structured programme of community engagement, and nurturing a more sustainable public sphere, including the building of a more dialectical relationship between the Dialogues and civil society.
- Full Text:
- Date Issued: 2010
- Authors: Amner, Roderick John
- Date: 2010
- Subjects: Daily Dispatch (East London, South Africa) Journalism -- South Africa -- East London Citizen journalism -- South Africa -- East London
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3417 , http://hdl.handle.net/10962/d1002870
- Description: This thesis critically examines the nature and purpose of a series of four town-hall-like meetings, the Community Dialogues, held in the townships and suburbs of East London, South Africa, in 2009. They were undertaken by a mainstream, commercial newspaper, the Daily Dispatch, under the banner of the worldwide public journalism movement. Following Christians et al (2009), the thesis sets out a normative framework of media performance in a democracy, including a detailed and critical normative theory of the ‘facilitative role’ proposed and developed by Haas (2007), one of the public journalism movement’s key advocate-theorists. It also draws on a variety of theoretical frameworks and perspectives in the fields of Political Studies and Media Studies to provide an analytical overview of the complex matrix of political and media contexts – at the macro (global), meso (national) and micro (local) levels – that have helped give impetus to the Community Dialogues and also shaped their ongoing operation as a public journalism strategy in the South African context. Following a critical realist case study design, the thesis goes on to provide a narrative account of the Dialogues based on in-depth interviews exploring the motivations, self-understandings and perceptions of those journalists who originated, directed and participated in this project, as well as observation of a Community Dialogue, and an examination of some of the journalistic texts related to the Dialogues. This primary data is then critically evaluated against normative theories of press performance, especially Haas’s ‘public philosophy’ of public journalism. The thesis found that apart from their undoubted success in generating a more comprehensive and representative news agenda for the newspaper, the Dialogues often fell short of Habermas’s (1989) proceduralist-discursive notion of the ‘deliberating public’, which sees citizens share a commitment to engage in common deliberation and public problem solving. This can be attributed to a number of problems, including some important theoretical/conceptual weaknesses in the Community Dialogues’ project design, the relative immaturity of the project, the domination of civil society by political society in the South African political context, and a number of organisational constraints at the Daily Dispatch. On the other hand, the newspaper’s editorial leadership has shown clear commitment to the idea of expanding the project in the future, establishing a more a more structured programme of community engagement, and nurturing a more sustainable public sphere, including the building of a more dialectical relationship between the Dialogues and civil society.
- Full Text:
- Date Issued: 2010
Democratic leadership and management practices in a rural Namibian secondary school
- Authors: Mabuku, Robert Nalisa
- Date: 2010
- Subjects: Educational leadership -- Namibia -- Case studies School management and organization -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Educational change -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1489 , http://hdl.handle.net/10962/d1003370
- Description: The primary purpose of this research was to investigate the understanding and implementation of democratic leadership and management in schools by school managers and other members of the school community in leadership and management roles as advocated by the policy of Education for all. The study also aimed at identifying any gaps in the understanding and practice of the participants in order to enhance democratic leadership and management in schools. Qualitative research using the interpretive approach was the methodology employed in order to fulfill the intention of the study, namely to investigate the participants` experiences and understanding of democratic education leadership and management. The case study method was appropriate to understand the meanings the participants attached to their practice in their natural setting. Data were collected by using semi-structured interviews, document analysis, and observation. The sample for the study consisted of ten participants: the principal, the head of department, two School Board members, two senior teachers, two Learner Representative Council members and two class captains. The findings suggest that the participants understood and practised democratic ELM in terms of broader participation, open communication, delegation for empowerment, learning organisation, shared decision-making, shared leadership and teamwork. However, the data suggest areas of concern in the participants` understanding and implementation of the policy which could be strengthened to entrench the policy. The study recommends that education policy makers, education managers, school managers, teachers, parents and learners all work towards improving democratic ELM in schools. In order to achieve this objective, policy makers are urged to avoid ambiguity to enable all implementers to fully understand policies. Education managers could ensure school-wide training on the policy while school managers and other stakeholders should engage in self-reflection and introspection and be more proactive towards improving their own understanding and practice.
- Full Text:
- Date Issued: 2010
- Authors: Mabuku, Robert Nalisa
- Date: 2010
- Subjects: Educational leadership -- Namibia -- Case studies School management and organization -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Educational change -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1489 , http://hdl.handle.net/10962/d1003370
- Description: The primary purpose of this research was to investigate the understanding and implementation of democratic leadership and management in schools by school managers and other members of the school community in leadership and management roles as advocated by the policy of Education for all. The study also aimed at identifying any gaps in the understanding and practice of the participants in order to enhance democratic leadership and management in schools. Qualitative research using the interpretive approach was the methodology employed in order to fulfill the intention of the study, namely to investigate the participants` experiences and understanding of democratic education leadership and management. The case study method was appropriate to understand the meanings the participants attached to their practice in their natural setting. Data were collected by using semi-structured interviews, document analysis, and observation. The sample for the study consisted of ten participants: the principal, the head of department, two School Board members, two senior teachers, two Learner Representative Council members and two class captains. The findings suggest that the participants understood and practised democratic ELM in terms of broader participation, open communication, delegation for empowerment, learning organisation, shared decision-making, shared leadership and teamwork. However, the data suggest areas of concern in the participants` understanding and implementation of the policy which could be strengthened to entrench the policy. The study recommends that education policy makers, education managers, school managers, teachers, parents and learners all work towards improving democratic ELM in schools. In order to achieve this objective, policy makers are urged to avoid ambiguity to enable all implementers to fully understand policies. Education managers could ensure school-wide training on the policy while school managers and other stakeholders should engage in self-reflection and introspection and be more proactive towards improving their own understanding and practice.
- Full Text:
- Date Issued: 2010
Demographical diversity influence on online shopping orientation and propensity to buy online
- Authors: Tapson, Megan Jacqueline
- Date: 2010
- Subjects: Teleshopping -- South Africa , Electronic commerce -- South Africa , Consumer behavior -- South Africa -- Cross-cultural studies , Ethnicity -- South Africa , Ethnic attitudes -- South Africa , Consumer behavior -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:1168 , http://hdl.handle.net/10962/d1002784 , Teleshopping -- South Africa , Electronic commerce -- South Africa , Consumer behavior -- South Africa -- Cross-cultural studies , Ethnicity -- South Africa , Ethnic attitudes -- South Africa , Consumer behavior -- South Africa
- Description: Online shopping is a growing phenomenon all over the world, and it has thus had an influence on the shopping process for many consumers (Brengman et al., 2005:79; Brown et al., 2003:1667; Kau et al., 2003:139). Consumers are now choosing to shop online due to changes in their lifestyles and demographic diversity (Kau et al., 2003:139). The purpose of this research was to examine the extent to which demographic diversity influenced online shopping orientation and propensity to buy online. The researcher first conducted an in-depth theoretical study of previous research into demographic diversity, online shopping orientation and propensity to buy online. Next, the researcher conducted an empirical survey questionnaire, in order to assess the opinions of students at the three selected Eastern Cape universities. Phinney's (1992:156) multi-group ethnic identity measure was administered in order to identify how respondents feel about their ethnicity and/or how they react to their own ethnic group. Kau et al.,'s (2003) online shopping orientation measure was used to help identify six relevant online shopping factors. The six online shopping factors where then used to describe six online shopping orientation types. The main findings of this research conducted at three Universities in the Eastern Cape can be summarised as follows: Ethnic Identity Profile: - Within this research it was found that respondents at all three universities in general had a strong ethnic identity to their specified ethnic group, according to the two ethnic identity factors namely; commitment and exploration. Online Shopping Orientation Profile: - Within this research it was found that the respondents at all three universities in general could be categorised in one of six online shopping orientation types according to six online shopping factors. The extent to which demographic diversity influences types of online shopping orientation: - From the research hypotheses it was concluded that a relationship exists between demographic diversity and types of online shopping orientations, whereby the gender, race and ethnicity of respondent is likely to influence the way consumers shop online, namely the consumers‟ online shopping orientation. The extent to which demographic diversity influences propensity to buy online: - From the research hypotheses it was concluded that a relationship exists between demographic diversity and propensity to buy online, whereby the gender of respondents is likely to influence whether consumers buy online in the future. - From the research hypotheses it was concluded that no relationship exists between demographic diversity and propensity to buy online, whereby the race and ethnicity of respondents is not likely to influence whether consumers buy online in the future. The extent to which types of online shopping orientation influence propensity to buy online: - The findings suggest that different online shopping orientations have different propensities to buy online in the future. Hence, marketers should be aware of the online shopping orientations more likely to buy online in the future and focus their marketing programs on them. They should also try new ways to attract the online shopping orientations that may not buy online, in the hopes of changing their opinions and perceptions of the Internet and online shopping. South Africa, in particular, consists of multi-racial and diverse ethnic origins, which has resulted in a demographically diverse South African nation. Therefore, marketers need to develop a better understanding of consumers‟ online shopping orientation (Donthu and Garcia, 1999:57; Jayawardhena and Foley, 2000:19; Kau et al., 2003:140). Understanding consumers' online shopping orientation will assist marketers in being able to market to specific consumers and meet the needs of consumers effectively (Kau et al., 2003:140). Since demographic diversity influences the online shopping orientations of consumers, major opportunities for marketers will be provided by accommodating for a demographically diverse South African nation.
- Full Text:
- Date Issued: 2010
- Authors: Tapson, Megan Jacqueline
- Date: 2010
- Subjects: Teleshopping -- South Africa , Electronic commerce -- South Africa , Consumer behavior -- South Africa -- Cross-cultural studies , Ethnicity -- South Africa , Ethnic attitudes -- South Africa , Consumer behavior -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:1168 , http://hdl.handle.net/10962/d1002784 , Teleshopping -- South Africa , Electronic commerce -- South Africa , Consumer behavior -- South Africa -- Cross-cultural studies , Ethnicity -- South Africa , Ethnic attitudes -- South Africa , Consumer behavior -- South Africa
- Description: Online shopping is a growing phenomenon all over the world, and it has thus had an influence on the shopping process for many consumers (Brengman et al., 2005:79; Brown et al., 2003:1667; Kau et al., 2003:139). Consumers are now choosing to shop online due to changes in their lifestyles and demographic diversity (Kau et al., 2003:139). The purpose of this research was to examine the extent to which demographic diversity influenced online shopping orientation and propensity to buy online. The researcher first conducted an in-depth theoretical study of previous research into demographic diversity, online shopping orientation and propensity to buy online. Next, the researcher conducted an empirical survey questionnaire, in order to assess the opinions of students at the three selected Eastern Cape universities. Phinney's (1992:156) multi-group ethnic identity measure was administered in order to identify how respondents feel about their ethnicity and/or how they react to their own ethnic group. Kau et al.,'s (2003) online shopping orientation measure was used to help identify six relevant online shopping factors. The six online shopping factors where then used to describe six online shopping orientation types. The main findings of this research conducted at three Universities in the Eastern Cape can be summarised as follows: Ethnic Identity Profile: - Within this research it was found that respondents at all three universities in general had a strong ethnic identity to their specified ethnic group, according to the two ethnic identity factors namely; commitment and exploration. Online Shopping Orientation Profile: - Within this research it was found that the respondents at all three universities in general could be categorised in one of six online shopping orientation types according to six online shopping factors. The extent to which demographic diversity influences types of online shopping orientation: - From the research hypotheses it was concluded that a relationship exists between demographic diversity and types of online shopping orientations, whereby the gender, race and ethnicity of respondent is likely to influence the way consumers shop online, namely the consumers‟ online shopping orientation. The extent to which demographic diversity influences propensity to buy online: - From the research hypotheses it was concluded that a relationship exists between demographic diversity and propensity to buy online, whereby the gender of respondents is likely to influence whether consumers buy online in the future. - From the research hypotheses it was concluded that no relationship exists between demographic diversity and propensity to buy online, whereby the race and ethnicity of respondents is not likely to influence whether consumers buy online in the future. The extent to which types of online shopping orientation influence propensity to buy online: - The findings suggest that different online shopping orientations have different propensities to buy online in the future. Hence, marketers should be aware of the online shopping orientations more likely to buy online in the future and focus their marketing programs on them. They should also try new ways to attract the online shopping orientations that may not buy online, in the hopes of changing their opinions and perceptions of the Internet and online shopping. South Africa, in particular, consists of multi-racial and diverse ethnic origins, which has resulted in a demographically diverse South African nation. Therefore, marketers need to develop a better understanding of consumers‟ online shopping orientation (Donthu and Garcia, 1999:57; Jayawardhena and Foley, 2000:19; Kau et al., 2003:140). Understanding consumers' online shopping orientation will assist marketers in being able to market to specific consumers and meet the needs of consumers effectively (Kau et al., 2003:140). Since demographic diversity influences the online shopping orientations of consumers, major opportunities for marketers will be provided by accommodating for a demographically diverse South African nation.
- Full Text:
- Date Issued: 2010
Derivatives in emerging markets: a South African focus
- Authors: Schwegler, Stefan
- Date: 2010
- Subjects: Derivative securities , South Africa -- Economic conditions -- 21st century
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:9281 , http://hdl.handle.net/10948/1401 , Derivative securities , South Africa -- Economic conditions -- 21st century
- Description: This research focused on derivative instruments which are financial securities whose values are derived from the values of underlying assets, such as shares, bonds, currencies or interest rates. Derivatives are predominantly used to manage risks in portfolios (hedging) and trading (speculation). Derivatives have been used for centuries and have developed into one of the largest global financial markets. The most common derivative instruments available to investors are options, futures, swaps and contracts for difference, as they are fairly easy to understand and apply. During the 2008/2009 global financial crisis derivatives, especially credit derivatives, made headlines and although they did not cause the crisis, they accelerated it. Furthermore, the 2008/2009 financial crisis also increased the negative sentiments many investors have towards derivatives. As a result of the crisis the growth in the global derivatives market came to a halt for the first time in decades. In light of the above, the primary objective of this study was to gain a deeper understanding of derivatives trading in emerging markets, especially in the South African context, as these financial securities are very useful portfolio management tools. The aim of this study was to describe the current state of the South African derivatives market; to investigate the role that derivative instruments played in the 2008/2009 global financial crisis; and to identify the variables influencing investors’ decisions whether or not to include derivatives in their portfolios. Given the nature of the problem stated a qualitative or phenomenological research paradigm was adopted. This paradigm was deemed suitable given the exploratory nature of the research. Primary and secondary data for this study were obtained through semi-structured personal interviews with 21 experts in the South African financial services industry and through an extensive literature review, respectively. A research instrument, based on the literature review was developed to facilitate the interviewing process. The results of the empirical investigation show that although the majority of respondents use derivative instruments in managing their portfolios, the South African derivatives market is still in its development phase. Many investors do not use derivatives frequently as they lack knowledge about derivative instruments, receive uncompetitive prices, are restricted by rules and regulations as well as investment mandates. Fourteen variables were identified as having a possible impact on investors' decisions whether or not to use derivatives in their portfolios. The five variables identified in the empirical investigation as being the most important, were the level of information available and the transparency of price determination; investor’s knowledge of different derivative instruments; investor’s level of risk tolerance; the level of liquidity in the market; and investor's knowledge and familiarity with financial markets. The findings of this study suggest that financial institutions, selling and trading derivative instruments, should concentrate on these five variables to make derivatives more attractive investment alternatives for investors. In order for South African investors to consider derivatives as suitable investments more often, it is strongly recommended to educate investors better about these products and decrease the negative sentiments investors have towards derivatives. This should be done by showing and explaining to investors that derivatives are useful hedging and portfolio management tools. It is necessary to state the dangers and benefits of derivatives, as well as the features differentiating them. Financial institutions trading derivative instruments, local education facilities (e.g. universities) and financial markets related organisations should educate investors by providing various educational tools, such as online courses, booklets, seminars or presentations about derivative products on offer. Furthermore, it is highly recommended to make derivative markets more transparent through adequate and appropriate regulations. In that, investors are better protected from counterparty risks and trade in a safer environment due to clearing houses.
- Full Text:
- Date Issued: 2010
- Authors: Schwegler, Stefan
- Date: 2010
- Subjects: Derivative securities , South Africa -- Economic conditions -- 21st century
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:9281 , http://hdl.handle.net/10948/1401 , Derivative securities , South Africa -- Economic conditions -- 21st century
- Description: This research focused on derivative instruments which are financial securities whose values are derived from the values of underlying assets, such as shares, bonds, currencies or interest rates. Derivatives are predominantly used to manage risks in portfolios (hedging) and trading (speculation). Derivatives have been used for centuries and have developed into one of the largest global financial markets. The most common derivative instruments available to investors are options, futures, swaps and contracts for difference, as they are fairly easy to understand and apply. During the 2008/2009 global financial crisis derivatives, especially credit derivatives, made headlines and although they did not cause the crisis, they accelerated it. Furthermore, the 2008/2009 financial crisis also increased the negative sentiments many investors have towards derivatives. As a result of the crisis the growth in the global derivatives market came to a halt for the first time in decades. In light of the above, the primary objective of this study was to gain a deeper understanding of derivatives trading in emerging markets, especially in the South African context, as these financial securities are very useful portfolio management tools. The aim of this study was to describe the current state of the South African derivatives market; to investigate the role that derivative instruments played in the 2008/2009 global financial crisis; and to identify the variables influencing investors’ decisions whether or not to include derivatives in their portfolios. Given the nature of the problem stated a qualitative or phenomenological research paradigm was adopted. This paradigm was deemed suitable given the exploratory nature of the research. Primary and secondary data for this study were obtained through semi-structured personal interviews with 21 experts in the South African financial services industry and through an extensive literature review, respectively. A research instrument, based on the literature review was developed to facilitate the interviewing process. The results of the empirical investigation show that although the majority of respondents use derivative instruments in managing their portfolios, the South African derivatives market is still in its development phase. Many investors do not use derivatives frequently as they lack knowledge about derivative instruments, receive uncompetitive prices, are restricted by rules and regulations as well as investment mandates. Fourteen variables were identified as having a possible impact on investors' decisions whether or not to use derivatives in their portfolios. The five variables identified in the empirical investigation as being the most important, were the level of information available and the transparency of price determination; investor’s knowledge of different derivative instruments; investor’s level of risk tolerance; the level of liquidity in the market; and investor's knowledge and familiarity with financial markets. The findings of this study suggest that financial institutions, selling and trading derivative instruments, should concentrate on these five variables to make derivatives more attractive investment alternatives for investors. In order for South African investors to consider derivatives as suitable investments more often, it is strongly recommended to educate investors better about these products and decrease the negative sentiments investors have towards derivatives. This should be done by showing and explaining to investors that derivatives are useful hedging and portfolio management tools. It is necessary to state the dangers and benefits of derivatives, as well as the features differentiating them. Financial institutions trading derivative instruments, local education facilities (e.g. universities) and financial markets related organisations should educate investors by providing various educational tools, such as online courses, booklets, seminars or presentations about derivative products on offer. Furthermore, it is highly recommended to make derivative markets more transparent through adequate and appropriate regulations. In that, investors are better protected from counterparty risks and trade in a safer environment due to clearing houses.
- Full Text:
- Date Issued: 2010
Desktop control for a host apparatus of a digital multimedia network
- Gurdan, Robby, Foss, Richard
- Authors: Gurdan, Robby , Foss, Richard
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427070 , vital:72412 , https://patentimages.storage.googleapis.com/f6/97/d3/a66cc5c9e77021/US20100287491A1.pdf
- Description: The invention provides a desktop control and a browser for a host apparatus of a digital multimedia network. The desktop control comprises a processing core having at least one desk parameter link (DPL) to a device parameter of the host apparatus. Furthermore, the processing core can have at least one desk application link (DAL) to a browser application of the host apparatus. The processing core further has one or more desk item links to other desktop controls of another apparatus within the digital multimedia network.
- Full Text:
- Date Issued: 2010
- Authors: Gurdan, Robby , Foss, Richard
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427070 , vital:72412 , https://patentimages.storage.googleapis.com/f6/97/d3/a66cc5c9e77021/US20100287491A1.pdf
- Description: The invention provides a desktop control and a browser for a host apparatus of a digital multimedia network. The desktop control comprises a processing core having at least one desk parameter link (DPL) to a device parameter of the host apparatus. Furthermore, the processing core can have at least one desk application link (DAL) to a browser application of the host apparatus. The processing core further has one or more desk item links to other desktop controls of another apparatus within the digital multimedia network.
- Full Text:
- Date Issued: 2010
Developing a protocol for campus health service professional nurses to manage students with mental distress
- Authors: Dalton, Linda Louise
- Date: 2010
- Subjects: College students -- Mental health , College students -- Mental health services , Nurses -- Mental health , Distress (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10030 , http://hdl.handle.net/10948/1303 , College students -- Mental health , College students -- Mental health services , Nurses -- Mental health , Distress (Psychology)
- Description: Professional nurses working at a campus health service have to cope with challenges such as staff shortages and budgetary constraints associated with working in a complex environment providing primary health care. The aim of primary health care includes promoting health, preventing disease and the early detection and treatment of illness. Mental health services form an integral part of the integrated primary health care package as implemented in the campus health service. Students attend the Campus Health Service for help related to their health. Health care is provided by professional nurses and counsellors through a comprehensive primary health care service which serves students as well as staff. Some students may state that they experience feelings of being stressed or depressed. Other students may complain of physical symptoms such as headache or upper backache. Upon further investigation emotional problems may be identified as the cause of the psychosomatic symptoms. The professional nurses working in the campus health service verbalised that it is sometimes difficult to identify a mental illness or mental distress as there is no effective assessment tool that they can use. Management of conditions is also problematic as there are no protocols indicating the therapeutic interventions that can be taken. The research question in this study was therefore: What information should be included in a protocol to assess and manage a student experiencing mental distress that can be used by professional nurses working in a Campus Health Service? The aim of this study is to develop a mental health care protocol for campus health service professional nurses to assess and manage university students who are experiencing mental distress. The research design of this study was qualitative, explorative, descriptive, explanatory and contextual. In this study the Delphi research technique was used to create an instrument to standardise mental health care in a campus health service. The Delphi technique is a series of sequential questionnaires or “rounds” interspersed with controlled feedback that seeks to gain the most reliable consensus of opinion of a group of experts. A questionnaire was developed based on an extensive literature review. The research population of this study consisted of two groups: professional nurses with knowledge of student health care needs and expert psychiatric nurses. The study was conducted at the Campus Health Service at a university in the Eastern Cape. The data collection and analysis was done utilising the Delphi technique. Trustworthiness was ensured by using the Lincoln and Guba Model utilising the criteria of credibility, applicability, dependability and conformability. In this study the ethical principles of beneficence, non-maleficence, justice and self determination were applied to ensure that participants are treated with respect and consideration and ensured high ethical standards. Informed consent was obtained from the participants in this study. The findings of this research were utilised to assist the researcher in developing a protocol for mental health care of students in campus health service settings.
- Full Text:
- Date Issued: 2010
- Authors: Dalton, Linda Louise
- Date: 2010
- Subjects: College students -- Mental health , College students -- Mental health services , Nurses -- Mental health , Distress (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:10030 , http://hdl.handle.net/10948/1303 , College students -- Mental health , College students -- Mental health services , Nurses -- Mental health , Distress (Psychology)
- Description: Professional nurses working at a campus health service have to cope with challenges such as staff shortages and budgetary constraints associated with working in a complex environment providing primary health care. The aim of primary health care includes promoting health, preventing disease and the early detection and treatment of illness. Mental health services form an integral part of the integrated primary health care package as implemented in the campus health service. Students attend the Campus Health Service for help related to their health. Health care is provided by professional nurses and counsellors through a comprehensive primary health care service which serves students as well as staff. Some students may state that they experience feelings of being stressed or depressed. Other students may complain of physical symptoms such as headache or upper backache. Upon further investigation emotional problems may be identified as the cause of the psychosomatic symptoms. The professional nurses working in the campus health service verbalised that it is sometimes difficult to identify a mental illness or mental distress as there is no effective assessment tool that they can use. Management of conditions is also problematic as there are no protocols indicating the therapeutic interventions that can be taken. The research question in this study was therefore: What information should be included in a protocol to assess and manage a student experiencing mental distress that can be used by professional nurses working in a Campus Health Service? The aim of this study is to develop a mental health care protocol for campus health service professional nurses to assess and manage university students who are experiencing mental distress. The research design of this study was qualitative, explorative, descriptive, explanatory and contextual. In this study the Delphi research technique was used to create an instrument to standardise mental health care in a campus health service. The Delphi technique is a series of sequential questionnaires or “rounds” interspersed with controlled feedback that seeks to gain the most reliable consensus of opinion of a group of experts. A questionnaire was developed based on an extensive literature review. The research population of this study consisted of two groups: professional nurses with knowledge of student health care needs and expert psychiatric nurses. The study was conducted at the Campus Health Service at a university in the Eastern Cape. The data collection and analysis was done utilising the Delphi technique. Trustworthiness was ensured by using the Lincoln and Guba Model utilising the criteria of credibility, applicability, dependability and conformability. In this study the ethical principles of beneficence, non-maleficence, justice and self determination were applied to ensure that participants are treated with respect and consideration and ensured high ethical standards. Informed consent was obtained from the participants in this study. The findings of this research were utilised to assist the researcher in developing a protocol for mental health care of students in campus health service settings.
- Full Text:
- Date Issued: 2010
Developing a systematic model for the capturing and use of African oral poetry: the Bongani Sitole experience
- Authors: Mostert, André M
- Date: 2010
- Subjects: Sitole, Bongani, 1937- Communication and culture Oral tradition in literature Oral tradition -- Africa Ethnoscience -- Africa Folk poetry, African
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3579 , http://hdl.handle.net/10962/d1002154
- Description: Oral traditions and oral literature have long contributed to human communication. The advent of arguably the most important technology, the written word, altered human ability to create and develop. However, this development for all its potential and scope created one of the most insidious dichotomies. As the written word developed so too the oral word became devalued and pushed to the fringes of societal development. One of the unfortunate outcomes has been a focus on the nomenclatures associated with orality and oral tradition, which although of importance, has skewed where the focus could and should have been located, namely, how to support and maintain the oral word and its innate value to human society in the face of what has become rampant technological developments. It is now ironic that technology is creating a fecund environment for a rebirth of orality. The study aims to mobilize technauriture as a paradigm in order to further embed orality and oral traditions to coherently embrace this changing technological environment. The central tenet of the study is that in order to enhance the status of orality the innate value embodied in indigenous knowledge systems must be recognized. Using the work of Bongani Sitole, an oral poet, as a backdrop the study will demonstrate a basic model that can act as a foundation for the effective integration of orality into contemporary structures. This is based on work that I published in the Journal of African Contemporary Studies (2009). Given the obvious multi-disciplinary nature of the material the work covers a wide cross section of the debate, from questions of epistemology and knowledge in general in terms of oral traditions, through the consciousness and technical landscapes, via the experience with Sitole’s material to issues of copyright and ownership. This work has also been submitted for publication together with my supervisor as a co-author. The study intends to consolidate the technauriture debate and lay a solid foundation to support further study.
- Full Text:
- Date Issued: 2010
- Authors: Mostert, André M
- Date: 2010
- Subjects: Sitole, Bongani, 1937- Communication and culture Oral tradition in literature Oral tradition -- Africa Ethnoscience -- Africa Folk poetry, African
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3579 , http://hdl.handle.net/10962/d1002154
- Description: Oral traditions and oral literature have long contributed to human communication. The advent of arguably the most important technology, the written word, altered human ability to create and develop. However, this development for all its potential and scope created one of the most insidious dichotomies. As the written word developed so too the oral word became devalued and pushed to the fringes of societal development. One of the unfortunate outcomes has been a focus on the nomenclatures associated with orality and oral tradition, which although of importance, has skewed where the focus could and should have been located, namely, how to support and maintain the oral word and its innate value to human society in the face of what has become rampant technological developments. It is now ironic that technology is creating a fecund environment for a rebirth of orality. The study aims to mobilize technauriture as a paradigm in order to further embed orality and oral traditions to coherently embrace this changing technological environment. The central tenet of the study is that in order to enhance the status of orality the innate value embodied in indigenous knowledge systems must be recognized. Using the work of Bongani Sitole, an oral poet, as a backdrop the study will demonstrate a basic model that can act as a foundation for the effective integration of orality into contemporary structures. This is based on work that I published in the Journal of African Contemporary Studies (2009). Given the obvious multi-disciplinary nature of the material the work covers a wide cross section of the debate, from questions of epistemology and knowledge in general in terms of oral traditions, through the consciousness and technical landscapes, via the experience with Sitole’s material to issues of copyright and ownership. This work has also been submitted for publication together with my supervisor as a co-author. The study intends to consolidate the technauriture debate and lay a solid foundation to support further study.
- Full Text:
- Date Issued: 2010
Developing an e-health framework through electronic healthcare readiness assessment
- Authors: Coleman, Alfred
- Date: 2010
- Subjects: Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9729 , http://hdl.handle.net/10948/1519 , Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Description: The major socio-economic development challenges facing most African countries include economic diversification, poverty, unemployment, diseases and the unsustainable use of natural resources. The challenge of quality healthcare provisioning is compounded by the HIV/AIDS pandemic in Sub Saharan Africa. However, there is a great potential in using electronic healthcare (e-health) as one of the supportive systems within the healthcare sector to address these pressing challenges facing healthcare systems in developing countries, including solving inequalities in healthcare delivery between rural and urban hospitals/clinics. The purpose of this study was to compile a Provincial E-health Framework (PEHF) based on the feedback from electronic healthcare readiness assessments conducted in selected rural and urban hospitals/clinics in the North West Province in South Africa. The e-healthcare readiness assessment was conducted in the light of effective use of ICT in patient healthcare record system, consultation among healthcare professionals, prescription of medication, referral of patients and training of healthcare professionals in ICT usage. The study was divided into two phases which were phases 1 and 2 and a qualitative design supported by a case study approach was used. Data were collected using different techniques to enhance triangulation of data. The techniques included group interviews, qualitative questionnaires, photographs, document analysis and expert opinions. The outcome of the assessment led to the compilation of the PEHF which was based on Service Oriented Architecture (SOA). SOA was chosen to integrate the hospitals/clinics‟ ICT infrastructure yet allowing each hospital/clinic the autonomy to control its own ICT environment. To assist hospitals/clinics integrate their ICT resources, this research study proposed an Infrastructure Network Architecture which clustered hospitals/clinics to share common ICT infrastructure instead of duplicating these resources. Furthermore, processes of the e-health services (e-patient health IV record system, e-consultation system, e-prescription system, e-referral system and e-training system) were provided to assist in the implementation of the PEHF. Finally, a set of guidelines were provided by the research study to aid the implementation of the PEHF.
- Full Text:
- Date Issued: 2010
- Authors: Coleman, Alfred
- Date: 2010
- Subjects: Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9729 , http://hdl.handle.net/10948/1519 , Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Description: The major socio-economic development challenges facing most African countries include economic diversification, poverty, unemployment, diseases and the unsustainable use of natural resources. The challenge of quality healthcare provisioning is compounded by the HIV/AIDS pandemic in Sub Saharan Africa. However, there is a great potential in using electronic healthcare (e-health) as one of the supportive systems within the healthcare sector to address these pressing challenges facing healthcare systems in developing countries, including solving inequalities in healthcare delivery between rural and urban hospitals/clinics. The purpose of this study was to compile a Provincial E-health Framework (PEHF) based on the feedback from electronic healthcare readiness assessments conducted in selected rural and urban hospitals/clinics in the North West Province in South Africa. The e-healthcare readiness assessment was conducted in the light of effective use of ICT in patient healthcare record system, consultation among healthcare professionals, prescription of medication, referral of patients and training of healthcare professionals in ICT usage. The study was divided into two phases which were phases 1 and 2 and a qualitative design supported by a case study approach was used. Data were collected using different techniques to enhance triangulation of data. The techniques included group interviews, qualitative questionnaires, photographs, document analysis and expert opinions. The outcome of the assessment led to the compilation of the PEHF which was based on Service Oriented Architecture (SOA). SOA was chosen to integrate the hospitals/clinics‟ ICT infrastructure yet allowing each hospital/clinic the autonomy to control its own ICT environment. To assist hospitals/clinics integrate their ICT resources, this research study proposed an Infrastructure Network Architecture which clustered hospitals/clinics to share common ICT infrastructure instead of duplicating these resources. Furthermore, processes of the e-health services (e-patient health IV record system, e-consultation system, e-prescription system, e-referral system and e-training system) were provided to assist in the implementation of the PEHF. Finally, a set of guidelines were provided by the research study to aid the implementation of the PEHF.
- Full Text:
- Date Issued: 2010
Developing an ionospheric map for South Africa
- McKinnell, Lee-Anne, Okoh, D I, Cilliers, P J
- Authors: McKinnell, Lee-Anne , Okoh, D I , Cilliers, P J
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6822 , http://hdl.handle.net/10962/d1004438 , http://dx.doi.org/10.5194/angeo-28-1431-2010
- Description: The development of a map of the ionosphere over South Africa is presented in this paper. The International Reference Ionosphere (IRI) model, South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were combined within their own limitations to develop an accurate representation of the South African ionosphere. The map is essentially in the form of a computer program that shows spatial and temporal representations of the South African ionosphere for a given set of geophysical parameters. A validation of the map is attempted using a comparison of Total Electron Content (TEC) values derived from the map, from the IRI model, and from Global Positioning System (GPS) measurements. It is foreseen that the final South African ionospheric map will be implemented as a Space Weather product of the African Space Weather Regional Warning Centre.
- Full Text:
- Date Issued: 2010
- Authors: McKinnell, Lee-Anne , Okoh, D I , Cilliers, P J
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6822 , http://hdl.handle.net/10962/d1004438 , http://dx.doi.org/10.5194/angeo-28-1431-2010
- Description: The development of a map of the ionosphere over South Africa is presented in this paper. The International Reference Ionosphere (IRI) model, South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were combined within their own limitations to develop an accurate representation of the South African ionosphere. The map is essentially in the form of a computer program that shows spatial and temporal representations of the South African ionosphere for a given set of geophysical parameters. A validation of the map is attempted using a comparison of Total Electron Content (TEC) values derived from the map, from the IRI model, and from Global Positioning System (GPS) measurements. It is foreseen that the final South African ionospheric map will be implemented as a Space Weather product of the African Space Weather Regional Warning Centre.
- Full Text:
- Date Issued: 2010
Developing SOA wrappers for communication purposes in rural areas
- Authors: Samalenge, Jimmy
- Date: 2010
- Subjects: Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11386 , http://hdl.handle.net/10353/320 , Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Description: The introduction of Web Services as a platform upon which applications can communicate has contributed a great deal towards the expansion of World Wide Web technologies. The Internet and computing technologies have been some of the factors that have contributed to the socio-economic improvement of urban and industrial areas. This research focuses on the application of Service-Oriented Architecture (SOA) and Web Services technologies in Information and Communication Technologies for Development (ICT4D) contexts. SOA is a style used to design distributed systems, and Web Services are some of the common realizations of the SOA. Web Services allow the exchange of data between two or more machines in a simple and standardized manner over the network. This has resulted in the augmentation of ways in which individuals in a society and in the world communicate. This research aims to develop a SOA-based system with services that are implemented as Web Services. The system is intended to support communication activities of Dwesa community members. The communication methods identified as the most commonly used in the Dwesa community are Short Message Services (SMSs) and voice calls. In this research we have identified further methods (i.e. Multimedia Message Service, Electronic mail and Instant Messaging) to augment communication activities in Dwesa. The developed system, therefore, exposes SMS Web Service, MMS Web Service, Email Web Service and IM Web Service that are consumed in machine-to-machine, machine-to-person and person-to-person types of communication. We have also implemented a one-stop communication shop, through a web portal which provides interfaces to the different communication modules. Elaborate functional and usability testing have also been undertaken to establish the viability and end-user acceptance of the system respectively. This research has provided the initial validation of the effectiveness of the SOA-based system in ICT4D contexts
- Full Text:
- Date Issued: 2010
- Authors: Samalenge, Jimmy
- Date: 2010
- Subjects: Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11386 , http://hdl.handle.net/10353/320 , Computer network architectures , Computer architecture , Computer software -- Specifications , Rural development projects -- South Africa -- Eastern Cape , Web services , System design , Technological innovations -- South Africa -- Eastern Cape
- Description: The introduction of Web Services as a platform upon which applications can communicate has contributed a great deal towards the expansion of World Wide Web technologies. The Internet and computing technologies have been some of the factors that have contributed to the socio-economic improvement of urban and industrial areas. This research focuses on the application of Service-Oriented Architecture (SOA) and Web Services technologies in Information and Communication Technologies for Development (ICT4D) contexts. SOA is a style used to design distributed systems, and Web Services are some of the common realizations of the SOA. Web Services allow the exchange of data between two or more machines in a simple and standardized manner over the network. This has resulted in the augmentation of ways in which individuals in a society and in the world communicate. This research aims to develop a SOA-based system with services that are implemented as Web Services. The system is intended to support communication activities of Dwesa community members. The communication methods identified as the most commonly used in the Dwesa community are Short Message Services (SMSs) and voice calls. In this research we have identified further methods (i.e. Multimedia Message Service, Electronic mail and Instant Messaging) to augment communication activities in Dwesa. The developed system, therefore, exposes SMS Web Service, MMS Web Service, Email Web Service and IM Web Service that are consumed in machine-to-machine, machine-to-person and person-to-person types of communication. We have also implemented a one-stop communication shop, through a web portal which provides interfaces to the different communication modules. Elaborate functional and usability testing have also been undertaken to establish the viability and end-user acceptance of the system respectively. This research has provided the initial validation of the effectiveness of the SOA-based system in ICT4D contexts
- Full Text:
- Date Issued: 2010
Development and assessment of minocycline sustained release capsule formulations
- Sachikonye, Tinotenda Chipo Victoria
- Authors: Sachikonye, Tinotenda Chipo Victoria
- Date: 2010
- Subjects: Drugs -- Controlled release , Drugs -- Dosage forms , Capsules (Pharmacy) , Drugs -- Administration , Acne -- Treatment , Tetracyclines , Antibiotics -- Side effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3854 , http://hdl.handle.net/10962/d1013127
- Description: The use of minocycline for the treatment of a broad range of systemic infections and for severe acne has been associated with vestibular side effects. The severity of side effects may lead to poor adherence to therapy by patients. The use of sustained release formulations of minocycline that display slow dissolution of minocycline following administration may be beneficial in reducing the incidence and severity of side effects. Therefore, sustained release capsule dosage forms containing 100 mg minocycline (base) were manufactured and assessed for use as sustained release oral dosage forms of minocycline. Minocycline sustained release capsules were manufactured based on matrix technologies using hydroxypropylmethyl cellulose (HPMC) and Compritol® as release retarding polymers. The rate and extent of minocycline release from the capsules was evaluated using USP Apparatus 1 and samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection. Differences in the rate and extent of minocycline release from formulations manufactured using HPMC or Compritol® were influenced by the concentration of polymer used in the formulations. The rate and extent of minocycline release was faster and greater when low concentrations of polymer were used in formulations. The effect of different excipients on the release pattern(s) of minocycline and particularly their potential to optimise minocycline release from experimental formulations was investigated. The use of diluents such as lactose and microcrystalline cellulose (MCC) revealed that lactose facilitated minocycline release when HPMC was used as the polymer matrix. In contrast, the use of lactose as diluent resulted in slower release of minocycline from Compritol® based formulations. The addition of sodium starch glycolate to HPMC based formulations resulted in slower release of minocycline than when no sodium starch glycolate was used. Compritol® based formulations were observed to release minocycline faster following addition of sodium starch glycolate and Poloxamer 188 to experimental formulations. In vitro dissolution profiles were compared to a target or reference profile using the difference and similarity factors, ƒ1 and ƒ2 , and a one way analysis of variance (ANOVA). In addition, the mechanism of minocycline release was elucidated following fitting of dissolution data to the Korsmeyer-Peppas, Higuchi and Zero order models. Minocycline release kinetics were best described by the Korsmeyer-Peppas model and the values of the release exponent, n (italics), revealed that drug release was a result of the combined effects of minocycline diffusion through matrices and erosion of the matrices. These in vitro dissolution profiles were better fit to the Higuchi model than to the Zero order model. Two formulations that displayed a fit to the Zero order model were identified for further studies as potential dosage forms for sustained release minocycline.
- Full Text:
- Date Issued: 2010
- Authors: Sachikonye, Tinotenda Chipo Victoria
- Date: 2010
- Subjects: Drugs -- Controlled release , Drugs -- Dosage forms , Capsules (Pharmacy) , Drugs -- Administration , Acne -- Treatment , Tetracyclines , Antibiotics -- Side effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3854 , http://hdl.handle.net/10962/d1013127
- Description: The use of minocycline for the treatment of a broad range of systemic infections and for severe acne has been associated with vestibular side effects. The severity of side effects may lead to poor adherence to therapy by patients. The use of sustained release formulations of minocycline that display slow dissolution of minocycline following administration may be beneficial in reducing the incidence and severity of side effects. Therefore, sustained release capsule dosage forms containing 100 mg minocycline (base) were manufactured and assessed for use as sustained release oral dosage forms of minocycline. Minocycline sustained release capsules were manufactured based on matrix technologies using hydroxypropylmethyl cellulose (HPMC) and Compritol® as release retarding polymers. The rate and extent of minocycline release from the capsules was evaluated using USP Apparatus 1 and samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection. Differences in the rate and extent of minocycline release from formulations manufactured using HPMC or Compritol® were influenced by the concentration of polymer used in the formulations. The rate and extent of minocycline release was faster and greater when low concentrations of polymer were used in formulations. The effect of different excipients on the release pattern(s) of minocycline and particularly their potential to optimise minocycline release from experimental formulations was investigated. The use of diluents such as lactose and microcrystalline cellulose (MCC) revealed that lactose facilitated minocycline release when HPMC was used as the polymer matrix. In contrast, the use of lactose as diluent resulted in slower release of minocycline from Compritol® based formulations. The addition of sodium starch glycolate to HPMC based formulations resulted in slower release of minocycline than when no sodium starch glycolate was used. Compritol® based formulations were observed to release minocycline faster following addition of sodium starch glycolate and Poloxamer 188 to experimental formulations. In vitro dissolution profiles were compared to a target or reference profile using the difference and similarity factors, ƒ1 and ƒ2 , and a one way analysis of variance (ANOVA). In addition, the mechanism of minocycline release was elucidated following fitting of dissolution data to the Korsmeyer-Peppas, Higuchi and Zero order models. Minocycline release kinetics were best described by the Korsmeyer-Peppas model and the values of the release exponent, n (italics), revealed that drug release was a result of the combined effects of minocycline diffusion through matrices and erosion of the matrices. These in vitro dissolution profiles were better fit to the Higuchi model than to the Zero order model. Two formulations that displayed a fit to the Zero order model were identified for further studies as potential dosage forms for sustained release minocycline.
- Full Text:
- Date Issued: 2010
Development of a stability-indicating high performance liquid chromatographic method for the analysis of topiramate and dissolution rate testing in topiramate tablets
- Mohammadi, Ali, Rezanour, Nasrin, Ansari Dogaheh, M, Walker, Roderick B
- Authors: Mohammadi, Ali , Rezanour, Nasrin , Ansari Dogaheh, M , Walker, Roderick B
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:6412 , http://hdl.handle.net/10962/d1006507
- Description: A stability-indicating high performance liquid chromatographic(HPLC) method was developed and validated for the quantitation and dissolution determination of topiramate in tablet dosage forms. An isocratic separation was achieved using a phenyl column with a flow rate of 1 mL/min using UV detection at 264 nm. Topiramate has low UV absorbtivity and was subjected to derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl). The mobile phase for the separation consisted of acetonitrile: 50 mM sodium dihydrogen phosphate(NaH2PO4) containing 3 % v/v triethylamine (pH 2.8) in a 48:52 v/v ratio. Topiramate was subjected to oxidation, hydrolysis, photolysis and heat for the purposes of stress testing. Separation was achieved for the parent compound and all the degradation products in an overall analytical run time of approximately 15 min with the parent compound topiramate eluting at approximately 9.2 min. The method was linear over the concentration range of 1-100 μg/mL (r = 0.9996) with limits of quantitation and detection of 1 and 0.3 μg/mL, respectively.
- Full Text:
- Date Issued: 2010
- Authors: Mohammadi, Ali , Rezanour, Nasrin , Ansari Dogaheh, M , Walker, Roderick B
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:6412 , http://hdl.handle.net/10962/d1006507
- Description: A stability-indicating high performance liquid chromatographic(HPLC) method was developed and validated for the quantitation and dissolution determination of topiramate in tablet dosage forms. An isocratic separation was achieved using a phenyl column with a flow rate of 1 mL/min using UV detection at 264 nm. Topiramate has low UV absorbtivity and was subjected to derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl). The mobile phase for the separation consisted of acetonitrile: 50 mM sodium dihydrogen phosphate(NaH2PO4) containing 3 % v/v triethylamine (pH 2.8) in a 48:52 v/v ratio. Topiramate was subjected to oxidation, hydrolysis, photolysis and heat for the purposes of stress testing. Separation was achieved for the parent compound and all the degradation products in an overall analytical run time of approximately 15 min with the parent compound topiramate eluting at approximately 9.2 min. The method was linear over the concentration range of 1-100 μg/mL (r = 0.9996) with limits of quantitation and detection of 1 and 0.3 μg/mL, respectively.
- Full Text:
- Date Issued: 2010
Development of an IMS Compliant, Cross Platform Client Using the JAIN SIP Applet Phone
- Muswera, Walter T, Terzoli, Alfredo
- Authors: Muswera, Walter T , Terzoli, Alfredo
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431274 , vital:72760 , https://www.cs.ru.ac.za/research/g09M3278/Muswera.pdf
- Description: Several open source SIP/IMS Clients are currently in use in the Rhodes University Convergence Research Group. However, there is no single Client that provides researchers with all the required functionality need-ed to test the applications they have developed. Integrating advanced features into a single Client can help to speed up testing as well as pro-vide a variety of innovative communication services. In this paper we present an overview of two popular SIP/IMS Clients currently in use. We also discuss the features and design architecture of a Client called JAIN SIP Applet Phone (JSAP) which will be used as a basis for the development of a new IMS compliant Client. We then analyse what functionality JSAP lacks and propose features that need to be imple-mented.
- Full Text:
- Date Issued: 2010
- Authors: Muswera, Walter T , Terzoli, Alfredo
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431274 , vital:72760 , https://www.cs.ru.ac.za/research/g09M3278/Muswera.pdf
- Description: Several open source SIP/IMS Clients are currently in use in the Rhodes University Convergence Research Group. However, there is no single Client that provides researchers with all the required functionality need-ed to test the applications they have developed. Integrating advanced features into a single Client can help to speed up testing as well as pro-vide a variety of innovative communication services. In this paper we present an overview of two popular SIP/IMS Clients currently in use. We also discuss the features and design architecture of a Client called JAIN SIP Applet Phone (JSAP) which will be used as a basis for the development of a new IMS compliant Client. We then analyse what functionality JSAP lacks and propose features that need to be imple-mented.
- Full Text:
- Date Issued: 2010
Development of insulin resistance in a rat model and the effects of sutherlandia frutescens as treatment and prevention
- Authors: Mackenzie, Janine
- Date: 2010
- Subjects: Metabolic syndrome , Insulin resistance -- Animal models , Obesity -- Treatment
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10340 , http://hdl.handle.net/10948/d1016216
- Description: The global number of obese people has reached pandemic proportions. High caloric diets and reduced physical exercise are to blame for this growing epidemic. Obesity has a very complex association with several other metabolic disorders, such as insulin resistance (IR), diabetes mellitus type 2 (DMT2) and cardiovascular disease. This puts a huge burden on health care systems world wide and claims many lives. Sutherlandia frutescens is a traditionally used herb, which is known to have anti-diabetic properties. However, the direct mode of action of S. frutescens still remains to be elucidated. The aim of this study was to investigate the developmental stages of high fat diet (HFD)-induced IR, to illuminate the pathogenesis of IR with a focal point on modifications in the lipid metabolism. Furthermore, the effects of S. frutescens as a treatment or prevention drug for IR and associated metabolic changes were examined. Two sets of experiments were conducted on male Wistar rats. In the first experiment rats, one week post weaning received a low fat diet (LFD), high fat diet (HFD) or HFD supplemented with S. frutescens (50mg/kg BW/d). Rats were sacrificed at week 0, 1, 2, 4, 8 and 12 in the feeding regime. In a second experiment rats were fed with a LFD or a HFD for 12 weeks and treated thereafter with S. frutescens (50mg/kg BW/d), metformin (13mg/kg BW/d) or water (control) for 28 days. Rats in the second experiment were sacrificed at week 12 to confirm IR while concurrently run rats were sacrificed after 28 days of treatment. For all the experiments rats were anaesthetized, blood was removed and rats were dissected. Plasma samples were analyzed for insulin, glucose, blood lipid parameters and cytokines. Liver, muscle and adipose tissue were analyzed for glucose uptake, total lipid content, lipid profile and fatty acid profile. It was shown that the intake of HFD caused IR and hyperinsulinaemia. The developmental stages in experiment one confirmed that an increase in plasma free fatty acids preceeded the onset of IR. Plasma and tissue lipid parameters (free fatty acid-, triglyceride- and cholesterol concentrations) showed pathological modifications in the HFD group. An ectopic accumulation of fat was observed in muscle and liver, as well as a change in membrane fatty acid profile. The results for circulating cytokines were somewhat inconclusive. Rats supplemented with S. frutescens did not develop HFD-induced IR (study one) or IR was reversed (study two). S. frutescens treatment also resulted in positive changes in plasma and tissue lipid parameters. In summary, an animal model for HFD-induced IR was established and the detrimental effect of elevated plasma FFA on glucose and lipid metabolism was observed. A novel discovery suggests that the anti-diabetic mode of action of S. frutescens is through modulation of lipid metabolism. It was also established that S. frutescens has the potential to prevent IR in vivo.
- Full Text:
- Date Issued: 2010
- Authors: Mackenzie, Janine
- Date: 2010
- Subjects: Metabolic syndrome , Insulin resistance -- Animal models , Obesity -- Treatment
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10340 , http://hdl.handle.net/10948/d1016216
- Description: The global number of obese people has reached pandemic proportions. High caloric diets and reduced physical exercise are to blame for this growing epidemic. Obesity has a very complex association with several other metabolic disorders, such as insulin resistance (IR), diabetes mellitus type 2 (DMT2) and cardiovascular disease. This puts a huge burden on health care systems world wide and claims many lives. Sutherlandia frutescens is a traditionally used herb, which is known to have anti-diabetic properties. However, the direct mode of action of S. frutescens still remains to be elucidated. The aim of this study was to investigate the developmental stages of high fat diet (HFD)-induced IR, to illuminate the pathogenesis of IR with a focal point on modifications in the lipid metabolism. Furthermore, the effects of S. frutescens as a treatment or prevention drug for IR and associated metabolic changes were examined. Two sets of experiments were conducted on male Wistar rats. In the first experiment rats, one week post weaning received a low fat diet (LFD), high fat diet (HFD) or HFD supplemented with S. frutescens (50mg/kg BW/d). Rats were sacrificed at week 0, 1, 2, 4, 8 and 12 in the feeding regime. In a second experiment rats were fed with a LFD or a HFD for 12 weeks and treated thereafter with S. frutescens (50mg/kg BW/d), metformin (13mg/kg BW/d) or water (control) for 28 days. Rats in the second experiment were sacrificed at week 12 to confirm IR while concurrently run rats were sacrificed after 28 days of treatment. For all the experiments rats were anaesthetized, blood was removed and rats were dissected. Plasma samples were analyzed for insulin, glucose, blood lipid parameters and cytokines. Liver, muscle and adipose tissue were analyzed for glucose uptake, total lipid content, lipid profile and fatty acid profile. It was shown that the intake of HFD caused IR and hyperinsulinaemia. The developmental stages in experiment one confirmed that an increase in plasma free fatty acids preceeded the onset of IR. Plasma and tissue lipid parameters (free fatty acid-, triglyceride- and cholesterol concentrations) showed pathological modifications in the HFD group. An ectopic accumulation of fat was observed in muscle and liver, as well as a change in membrane fatty acid profile. The results for circulating cytokines were somewhat inconclusive. Rats supplemented with S. frutescens did not develop HFD-induced IR (study one) or IR was reversed (study two). S. frutescens treatment also resulted in positive changes in plasma and tissue lipid parameters. In summary, an animal model for HFD-induced IR was established and the detrimental effect of elevated plasma FFA on glucose and lipid metabolism was observed. A novel discovery suggests that the anti-diabetic mode of action of S. frutescens is through modulation of lipid metabolism. It was also established that S. frutescens has the potential to prevent IR in vivo.
- Full Text:
- Date Issued: 2010
Dialectics of dance and dress: the performative negotiation of Soli girl initiates (Moye) in Zambia
- Authors: Simbao, Ruth K
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147492 , vital:38643 , https://doi.org/10.1162/afar.2010.43.3.64
- Description: During a 2005 dance rehearsal in Nkomeshya Village near Lusaka, Zambia, a group of Soli girl initiates (moye) entered a clearing, slowly moving towards the drummer who beckoned them with her rhythmic eats. The girls per-formed a polite curtseying step, reflecting the meek modesty they are taught to display when they humbly greet elders or their future husbands with downcast eyes.
- Full Text:
- Date Issued: 2010
- Authors: Simbao, Ruth K
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147492 , vital:38643 , https://doi.org/10.1162/afar.2010.43.3.64
- Description: During a 2005 dance rehearsal in Nkomeshya Village near Lusaka, Zambia, a group of Soli girl initiates (moye) entered a clearing, slowly moving towards the drummer who beckoned them with her rhythmic eats. The girls per-formed a polite curtseying step, reflecting the meek modesty they are taught to display when they humbly greet elders or their future husbands with downcast eyes.
- Full Text:
- Date Issued: 2010
Die geskiedenis van Despatch, 1945-1995: 'n verkennende studie
- Authors: Steyn, Jacobus Pieter
- Date: 2010
- Subjects: Dispatch (South Africa) -- History , Afrikaners -- South Africa -- Despatch
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: vital:16142 , http://hdl.handle.net/10948/1116 , Dispatch (South Africa) -- History , Afrikaners -- South Africa -- Despatch
- Description: Hierdie studie se fokus is op die wit Afrikaanssprekende-gemeenskap van Despatch. Daar word op die sosiale, politieke en godsdienstige geskiedenis van die wit Afrikaanssprekende-gemeenskap op Despatch gekonsentreer. Die studie ondersoek slegs die geskiedenis van die wit Afrikaanssprekende-gemeenskap van Despatch aangesien die dorp bekend daarvoor is dat dit oorwegend ʼn wit Afrikaanssprekende-gemeenskap is. Die ekonomie van Despatch en die bruin en swart inwoners word egter kortliks bespreek. Die tydperk van hierdie studie handel van 1945 – 1995. Dit was tydens hierdie jare wat Despatch amptelik as ʼn munisipaliteit gefunksioneer het. Uit die aard van die saak moet die studie gebeure wat aanleiding tot die nedersetting van wit mense langs die oewer van die Swartkopsrivier bespreek. Daar word ʼn kort studie gemaak van die periode 1700 (toe die eerste wit mense hulle langs die oewers van die Swartkopsrivier gevestig het) tot 1939 (wat die begin was van permanente nedersettings langs die syspoor op Despatch). Sekere gebeure word verder as 1995 bespreek. Dit word gedoen om kontinuiteit te behou wanneer belangrike gebeurtenisse, soos die oorskakeling na demokratiese regering in 1994, ondersoek word. Die doel van die studie is om ʼn verkennende ondersoek rakende die geskiedenis van die wit Afrikaanssprekende-gemeenskap van Despatch te doen. Die studie is ʼn verkennende ondersoek omrede nie al die aspekte van die geskiedenis van Despatch ondersoek sal word nie. Slegs die wit Afrikaanssprekende-gemeenskap se sosiale strukture (onderwys, godsdiens en kultuur), munisipale bestuur en politiek sal ondersoek word.
- Full Text:
- Date Issued: 2010
- Authors: Steyn, Jacobus Pieter
- Date: 2010
- Subjects: Dispatch (South Africa) -- History , Afrikaners -- South Africa -- Despatch
- Language: Afrikaans
- Type: Thesis , Masters , MA
- Identifier: vital:16142 , http://hdl.handle.net/10948/1116 , Dispatch (South Africa) -- History , Afrikaners -- South Africa -- Despatch
- Description: Hierdie studie se fokus is op die wit Afrikaanssprekende-gemeenskap van Despatch. Daar word op die sosiale, politieke en godsdienstige geskiedenis van die wit Afrikaanssprekende-gemeenskap op Despatch gekonsentreer. Die studie ondersoek slegs die geskiedenis van die wit Afrikaanssprekende-gemeenskap van Despatch aangesien die dorp bekend daarvoor is dat dit oorwegend ʼn wit Afrikaanssprekende-gemeenskap is. Die ekonomie van Despatch en die bruin en swart inwoners word egter kortliks bespreek. Die tydperk van hierdie studie handel van 1945 – 1995. Dit was tydens hierdie jare wat Despatch amptelik as ʼn munisipaliteit gefunksioneer het. Uit die aard van die saak moet die studie gebeure wat aanleiding tot die nedersetting van wit mense langs die oewer van die Swartkopsrivier bespreek. Daar word ʼn kort studie gemaak van die periode 1700 (toe die eerste wit mense hulle langs die oewers van die Swartkopsrivier gevestig het) tot 1939 (wat die begin was van permanente nedersettings langs die syspoor op Despatch). Sekere gebeure word verder as 1995 bespreek. Dit word gedoen om kontinuiteit te behou wanneer belangrike gebeurtenisse, soos die oorskakeling na demokratiese regering in 1994, ondersoek word. Die doel van die studie is om ʼn verkennende ondersoek rakende die geskiedenis van die wit Afrikaanssprekende-gemeenskap van Despatch te doen. Die studie is ʼn verkennende ondersoek omrede nie al die aspekte van die geskiedenis van Despatch ondersoek sal word nie. Slegs die wit Afrikaanssprekende-gemeenskap se sosiale strukture (onderwys, godsdiens en kultuur), munisipale bestuur en politiek sal ondersoek word.
- Full Text:
- Date Issued: 2010
Diet and population trends of warthog in the Addo Elephant National Park
- Authors: Mgqatsa, Nokubonga
- Date: 2010
- Subjects: Warthog -- South Africa -- Addo Elelphant National Park
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10693 , http://hdl.handle.net/10948/1277 , Warthog -- South Africa -- Addo Elelphant National Park
- Description: The common warthog (Phacochoerus africanus) has recently been recognised as an alien invasive species in the Eastern Cape and their population is increasing rapidly within the region. This then raises a concern as it is recorded that invasive species have negative impacts on both economic and ecological aspects of biodiversity in the receiving community. There are few studies that have documented the impacts of this species in the Eastern Cape. This study therefore seeks to determine the diet and population trends of this species in the Addo Elephant National Park (AENP) Main Camp and the results obtained can be correlated with previous studies and used to quantify the impacts of this species in the Eastern Cape. Warthogs are specialized grazers, it was therefore hypothesized that they will have potential impacts on grazing resources in the AENP Main Camp. The diet of common warthogs in the AENP Main Camp was determined through microhistological analysis of faecal material of samples collected seasonally. Population trends of common warthogs were determined in relation to the effects of predation on the population growth and population age structure of these animals within the AENP Main Camp. The results were compared with the findings for common warthog population growth and population age structure of Great Fish River Nature Reserve (GFRNR), a predator free population. It was hypothesized that the population growth rate of common warthogs in the AENP Main Camp before the introduction of lions and hyaenas in the AENP would not differ from the population growth rate of common warthogs in GFRNR. Secondly, the post-lion/hyaena common warthog population in the AENP Main Camp would differ from both the AENP Main Camp pre-lion/hyaena and GFRNR common warthog populations due to the presence of large predators in the AENP Main Camp. For population age structure it was hypothesized that the two populations, AENP Main Camp and GFRNR would differ because of predators increasing mortality. The diet of common warthogs was dominated by grass (87.4 percent), with Cynodon dactylon being the dominant grass species. Common warthogs in the AENP Main Camp should be properly managed because they have potential impact on grasses. The population growth of common warthogs in the AENP Main Camp showed no effect of predation, with population growth not differing from that of GFRNR. Predation had an effect on common warthog population age structure with AENP Main Camp and GFRNR populations differing, particularly in terms of adult structure. Thus, population growth of common warthogs in the AENP Main Camp is not determined by the presence of predators. These findings highlight the status of common warthog as an invasive species in the AENP Main Camp and potentially impacting on grass species and show little effects of top-down population regulation. These results show a need of monitoring common warthog population as well as their potential impacts in the area.
- Full Text:
- Date Issued: 2010
- Authors: Mgqatsa, Nokubonga
- Date: 2010
- Subjects: Warthog -- South Africa -- Addo Elelphant National Park
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10693 , http://hdl.handle.net/10948/1277 , Warthog -- South Africa -- Addo Elelphant National Park
- Description: The common warthog (Phacochoerus africanus) has recently been recognised as an alien invasive species in the Eastern Cape and their population is increasing rapidly within the region. This then raises a concern as it is recorded that invasive species have negative impacts on both economic and ecological aspects of biodiversity in the receiving community. There are few studies that have documented the impacts of this species in the Eastern Cape. This study therefore seeks to determine the diet and population trends of this species in the Addo Elephant National Park (AENP) Main Camp and the results obtained can be correlated with previous studies and used to quantify the impacts of this species in the Eastern Cape. Warthogs are specialized grazers, it was therefore hypothesized that they will have potential impacts on grazing resources in the AENP Main Camp. The diet of common warthogs in the AENP Main Camp was determined through microhistological analysis of faecal material of samples collected seasonally. Population trends of common warthogs were determined in relation to the effects of predation on the population growth and population age structure of these animals within the AENP Main Camp. The results were compared with the findings for common warthog population growth and population age structure of Great Fish River Nature Reserve (GFRNR), a predator free population. It was hypothesized that the population growth rate of common warthogs in the AENP Main Camp before the introduction of lions and hyaenas in the AENP would not differ from the population growth rate of common warthogs in GFRNR. Secondly, the post-lion/hyaena common warthog population in the AENP Main Camp would differ from both the AENP Main Camp pre-lion/hyaena and GFRNR common warthog populations due to the presence of large predators in the AENP Main Camp. For population age structure it was hypothesized that the two populations, AENP Main Camp and GFRNR would differ because of predators increasing mortality. The diet of common warthogs was dominated by grass (87.4 percent), with Cynodon dactylon being the dominant grass species. Common warthogs in the AENP Main Camp should be properly managed because they have potential impact on grasses. The population growth of common warthogs in the AENP Main Camp showed no effect of predation, with population growth not differing from that of GFRNR. Predation had an effect on common warthog population age structure with AENP Main Camp and GFRNR populations differing, particularly in terms of adult structure. Thus, population growth of common warthogs in the AENP Main Camp is not determined by the presence of predators. These findings highlight the status of common warthog as an invasive species in the AENP Main Camp and potentially impacting on grass species and show little effects of top-down population regulation. These results show a need of monitoring common warthog population as well as their potential impacts in the area.
- Full Text:
- Date Issued: 2010