Bird-Monk Seding
- Authors: Rampolokeng, Lesego
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/5049 , vital:20758
- Description: This novella is made up of interlinked stories from a rural township in the North West province. The stories of this surface-tranquil place are told through descriptive passages, vignettes, snatches of dialogue, profiles and picture-postcards, all organically interwoven and entwined, and rendered in non-linear fashion. They are set in shebeens, shops, farmlands and the dusty empty spaces of the South African landscape, peopled by police, tourists, and prostitutes of all sorts. The pervasiveness of violence in all forms has the fictional narrator reflecting on the violence of his own past. A smattering of musicians' musings gleaned from interviews and album liner-notes helps him navigate his way through this morass, the rage and frustration that simmers beneath it all.
- Full Text:
- Authors: Rampolokeng, Lesego
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/5049 , vital:20758
- Description: This novella is made up of interlinked stories from a rural township in the North West province. The stories of this surface-tranquil place are told through descriptive passages, vignettes, snatches of dialogue, profiles and picture-postcards, all organically interwoven and entwined, and rendered in non-linear fashion. They are set in shebeens, shops, farmlands and the dusty empty spaces of the South African landscape, peopled by police, tourists, and prostitutes of all sorts. The pervasiveness of violence in all forms has the fictional narrator reflecting on the violence of his own past. A smattering of musicians' musings gleaned from interviews and album liner-notes helps him navigate his way through this morass, the rage and frustration that simmers beneath it all.
- Full Text:
Restructuring in higher education institutions: a case study of centralised cleaning services at Rhodes University
- Authors: Ntlokwana, Ziyanda
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3738 , vital:20540
- Description: The centralization of cleaners at Rhodes University has been the university’s response to the pressures put on higher education. This form of restructuring is the university’s attempt at dealing with the government’s cuts in funding despite the increasing demands placed on higher education institutions. The demands on universities necessitates that they compete on a global scale ,which sometimes sees many universities adopting a ‘neoliberal logic’ and as a result cutting labour costs to survive and compete. The aim of this study was to examine the nature and form of restructuring at Rhodes University and its impact on the workers’ lives. This research made use of both quantitative and qualitative research methods: namely, a quantitative survey that focused on the cleaners and in-depth interviews with trade union representatives. This research discovered that the restructuring programme at Rhodes University is different from that at other universities through its avoidance of outsourcing and the retrenchment of workers. Despite this tricky balance, however, the effects of this form of restructuring largely embody outsourcing characteristics and as a result disadvantage the cleaners.
- Full Text:
- Authors: Ntlokwana, Ziyanda
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3738 , vital:20540
- Description: The centralization of cleaners at Rhodes University has been the university’s response to the pressures put on higher education. This form of restructuring is the university’s attempt at dealing with the government’s cuts in funding despite the increasing demands placed on higher education institutions. The demands on universities necessitates that they compete on a global scale ,which sometimes sees many universities adopting a ‘neoliberal logic’ and as a result cutting labour costs to survive and compete. The aim of this study was to examine the nature and form of restructuring at Rhodes University and its impact on the workers’ lives. This research made use of both quantitative and qualitative research methods: namely, a quantitative survey that focused on the cleaners and in-depth interviews with trade union representatives. This research discovered that the restructuring programme at Rhodes University is different from that at other universities through its avoidance of outsourcing and the retrenchment of workers. Despite this tricky balance, however, the effects of this form of restructuring largely embody outsourcing characteristics and as a result disadvantage the cleaners.
- Full Text:
A study of barred preferential arrangements with applications to numerical approximation in electric circuits
- Authors: Nkonkobe, Sithembele
- Date: 2015
- Subjects: Electric circuits , Numerical calculations , Sequences (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5433 , http://hdl.handle.net/10962/d1020394
- Description: In 1854 Cayley proposed an interesting sequence 1,1,3,13,75,541,... in connection with analytical forms called trees. Since then there has been various combinatorial interpretations of the sequence. The sequence has been interpreted as the number of preferential arrangements of members of a set with n elements. Alternatively the sequence has been interpreted as the number of ordered partitions; the outcomes in races in which ties are allowed or geometrically the number of vertices, edges and faces of simplicial objects. An interesting application of the sequence is found in combination locks. The idea of a preferential arrangement has been extended to a wider combinatorial object called barred preferential arrangement with multiple bars. In this thesis we study barred preferential arrangements combinatorially with application to resistance of certain electrical circuits. In the process we derive some results on cyclic properties of the last digit of the number of barred preferential arrangements. An algorithm in python has been developed to find the number of barred preferential arrangements.
- Full Text:
- Authors: Nkonkobe, Sithembele
- Date: 2015
- Subjects: Electric circuits , Numerical calculations , Sequences (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5433 , http://hdl.handle.net/10962/d1020394
- Description: In 1854 Cayley proposed an interesting sequence 1,1,3,13,75,541,... in connection with analytical forms called trees. Since then there has been various combinatorial interpretations of the sequence. The sequence has been interpreted as the number of preferential arrangements of members of a set with n elements. Alternatively the sequence has been interpreted as the number of ordered partitions; the outcomes in races in which ties are allowed or geometrically the number of vertices, edges and faces of simplicial objects. An interesting application of the sequence is found in combination locks. The idea of a preferential arrangement has been extended to a wider combinatorial object called barred preferential arrangement with multiple bars. In this thesis we study barred preferential arrangements combinatorially with application to resistance of certain electrical circuits. In the process we derive some results on cyclic properties of the last digit of the number of barred preferential arrangements. An algorithm in python has been developed to find the number of barred preferential arrangements.
- Full Text:
Exploratory study : how do Somali shop owners (SSO) succeed in running businesses in Soweto : a South African perspective
- Authors: Mokitlane, Ofentse Clifford
- Date: 2014
- Subjects: Business enterprises, Foreign -- South Africa , Small business -- Management , Small business -- South Africa , Foreign workers -- South Africa , Employment in foreign countries , Entrepreneurship -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:842 , http://hdl.handle.net/10962/d1015653
- Description: This is a qualitative study which seeks to understand how Somali shop owners run successful businesses in the township of Soweto in South Africa. This research report has three sections, namely (1) the academic paper which comprises a shortened literature review, the research method, findings, and the discussion; (2) an extended literature review and (3) the research methodology. It is important to mention that these three sections are related and not necessarily stand-alone sections. Despite the hostilities faced by the Somali shop owners from the host communities in South Africa, it is notable that they are successful, small-sized entrepreneurs in most townships of South Africa (SA). Previous research on Somalis has predominantly focused on their assimilation into the societies in their host countries, and on how they are led into self-employment because of the unfavourable labour markets in the host country. In this vein, there is a need to understand how they run successful businesses in the townships of SA. This study seeks to answer the following research question: How Do Somali Shop Owners Succeed in Running Businesses in Soweto, South Africa (SA)? In pursuit of answers to the above research question, this study was confined to three locations in Soweto, namely Orlando West, Chiawelo and Rockville which have a relatively high number of Somali entrepreneurs who have been in operation for longer than three years. This qualitative study explored the multiple perspectives of reality of Somali shop owners. Purposively, 14 Somali shop owners were identified initially using purposive sampling. Subsequently, theoretical sampling was used to identify Somali shop owners who were interviewed regarding how they successfully run their businesses in the locations of Orlando West, Chiawelo and Rockville in the township of Soweto. A total of eighteen semi-structured, in-depth and face-to-face interviews were conducted with these shop owners as a means of gathering data to the point of saturating their perspectives. Data collection ceased when new perspectives were no longer evident as interviewees were being repetitive. Open-coding and constant comparison was used to analyse the data. The findings of the study show that ethnicity plays a predominant role in the success of the Somali shop owners. The intra-ethnic networks and trust-based support systems are pivotal to how Somali shop owners run successful businesses in Soweto. The key findings manifested showed that various forms of support came from Somali communities, family and fellow countrymen which were also central to their success. Another key finding showed that Somali shop owners run their businesses by complementing, rather than predominantly competing with the other local businesses, which ultimately differentiates them in this way. The study also revealed that responsiveness to local customer needs by enhancing the value of their business to the locality is also characteristic of how Somali shop owners build customer loyalty. This study contributes to our understanding of how Somali entrepreneurs conduct successful businesses in a hostile host country. The findings have implications for business development training and programmes which support immigrant entrepreneurs. The findings may also be extended to inform how business development programmes would be designed to equally support local entrepreneurs.
- Full Text:
- Authors: Mokitlane, Ofentse Clifford
- Date: 2014
- Subjects: Business enterprises, Foreign -- South Africa , Small business -- Management , Small business -- South Africa , Foreign workers -- South Africa , Employment in foreign countries , Entrepreneurship -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:842 , http://hdl.handle.net/10962/d1015653
- Description: This is a qualitative study which seeks to understand how Somali shop owners run successful businesses in the township of Soweto in South Africa. This research report has three sections, namely (1) the academic paper which comprises a shortened literature review, the research method, findings, and the discussion; (2) an extended literature review and (3) the research methodology. It is important to mention that these three sections are related and not necessarily stand-alone sections. Despite the hostilities faced by the Somali shop owners from the host communities in South Africa, it is notable that they are successful, small-sized entrepreneurs in most townships of South Africa (SA). Previous research on Somalis has predominantly focused on their assimilation into the societies in their host countries, and on how they are led into self-employment because of the unfavourable labour markets in the host country. In this vein, there is a need to understand how they run successful businesses in the townships of SA. This study seeks to answer the following research question: How Do Somali Shop Owners Succeed in Running Businesses in Soweto, South Africa (SA)? In pursuit of answers to the above research question, this study was confined to three locations in Soweto, namely Orlando West, Chiawelo and Rockville which have a relatively high number of Somali entrepreneurs who have been in operation for longer than three years. This qualitative study explored the multiple perspectives of reality of Somali shop owners. Purposively, 14 Somali shop owners were identified initially using purposive sampling. Subsequently, theoretical sampling was used to identify Somali shop owners who were interviewed regarding how they successfully run their businesses in the locations of Orlando West, Chiawelo and Rockville in the township of Soweto. A total of eighteen semi-structured, in-depth and face-to-face interviews were conducted with these shop owners as a means of gathering data to the point of saturating their perspectives. Data collection ceased when new perspectives were no longer evident as interviewees were being repetitive. Open-coding and constant comparison was used to analyse the data. The findings of the study show that ethnicity plays a predominant role in the success of the Somali shop owners. The intra-ethnic networks and trust-based support systems are pivotal to how Somali shop owners run successful businesses in Soweto. The key findings manifested showed that various forms of support came from Somali communities, family and fellow countrymen which were also central to their success. Another key finding showed that Somali shop owners run their businesses by complementing, rather than predominantly competing with the other local businesses, which ultimately differentiates them in this way. The study also revealed that responsiveness to local customer needs by enhancing the value of their business to the locality is also characteristic of how Somali shop owners build customer loyalty. This study contributes to our understanding of how Somali entrepreneurs conduct successful businesses in a hostile host country. The findings have implications for business development training and programmes which support immigrant entrepreneurs. The findings may also be extended to inform how business development programmes would be designed to equally support local entrepreneurs.
- Full Text:
What makes news on the front page? : an investigation of conceptions of newsworthiness in the East African Standard
- Authors: Nzioka, Roseleen M
- Date: 2013-06-19
- Subjects: East African Standard (Nairobi, Kenya) Journalism -- Social aspects -- Kenya Journalism -- Editing -- Kenya Newspapers -- Sections, columns, etc -- Kenya Mass media -- Political aspects -- Kenya Newspapers -- Kenya
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3519 , http://hdl.handle.net/10962/d1008178
- Description: Determining what is newsworthy is a daily challenge even to the very people who source news, produce and disseminate it. This study is part an exposition and exploration of the different approaches that media researchers have used to explain and determine the value of news. Like similar research before it, this study more specifically delves into the news selection process of news of one particular newspaper with the goal of investigating why and how news is selected for publication in the front page. News is the 'result of many forces: ranging from source power, journalistic orientation, medium-preference and market model, news values and production routines and processes. The study briefly expounds on the different definitions of news as perceived in terms of the developed and developing world. Just as journalists do not operate in a vacuum, a close examination of the various definitions reveals that news cannot be defined in isolation. Its definition is intrinsically tied to that of news values. Also explored here are debates about news values and their Western rootedness. Here reference is made to literature regarding theories on the social construction of meanings and on the gatekeeping concept.The study is informed by similar research in gatekeeping studies and sociology of news studies. It is important to state at the outset that the study is not concerned with how news is produced but why there is a bias for certain kinds of news. I am interested in explaining why and how the writers and editors at the East African Standard make decisions about what is worthy of being published on the front page of the newspaper. This distinction is necessary because the theories that inform this study transcend news sourcing and production. This study takes cognizance ofthe fact that one cannot separate social processes from the individual and vice versa. For this reason, this study investigates and analyses the biases of individual gatekeepers at the East African Standard as well as their collective biases. In the concluding section, this study calls for an alternative paradigm for journalism and news. The foregoing discussions in the other sections prove that a universal definition of news and what is newsworthy will not suffice and there is need to contexualise it.
- Full Text:
- Authors: Nzioka, Roseleen M
- Date: 2013-06-19
- Subjects: East African Standard (Nairobi, Kenya) Journalism -- Social aspects -- Kenya Journalism -- Editing -- Kenya Newspapers -- Sections, columns, etc -- Kenya Mass media -- Political aspects -- Kenya Newspapers -- Kenya
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3519 , http://hdl.handle.net/10962/d1008178
- Description: Determining what is newsworthy is a daily challenge even to the very people who source news, produce and disseminate it. This study is part an exposition and exploration of the different approaches that media researchers have used to explain and determine the value of news. Like similar research before it, this study more specifically delves into the news selection process of news of one particular newspaper with the goal of investigating why and how news is selected for publication in the front page. News is the 'result of many forces: ranging from source power, journalistic orientation, medium-preference and market model, news values and production routines and processes. The study briefly expounds on the different definitions of news as perceived in terms of the developed and developing world. Just as journalists do not operate in a vacuum, a close examination of the various definitions reveals that news cannot be defined in isolation. Its definition is intrinsically tied to that of news values. Also explored here are debates about news values and their Western rootedness. Here reference is made to literature regarding theories on the social construction of meanings and on the gatekeeping concept.The study is informed by similar research in gatekeeping studies and sociology of news studies. It is important to state at the outset that the study is not concerned with how news is produced but why there is a bias for certain kinds of news. I am interested in explaining why and how the writers and editors at the East African Standard make decisions about what is worthy of being published on the front page of the newspaper. This distinction is necessary because the theories that inform this study transcend news sourcing and production. This study takes cognizance ofthe fact that one cannot separate social processes from the individual and vice versa. For this reason, this study investigates and analyses the biases of individual gatekeepers at the East African Standard as well as their collective biases. In the concluding section, this study calls for an alternative paradigm for journalism and news. The foregoing discussions in the other sections prove that a universal definition of news and what is newsworthy will not suffice and there is need to contexualise it.
- Full Text:
Counting planes
- Authors: Rawlins, Isabel Bethan
- Date: 2013
- Subjects: Prose poems , Flash fiction , Short stories , English , Creative writing (Higher education) , Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century , South African poetry (English) -- 21st century , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5966 , http://hdl.handle.net/10962/d1001816
- Description: This collection of prose-poems and flash fiction, together with a few short stories, shows how romantic relationships colour our perspectives on the world. The collection has echoes throughout of speakers' voices, theme, imagery and tone. There is a narrative logic too, but working on a subtle level of echo and resonance
- Full Text:
- Authors: Rawlins, Isabel Bethan
- Date: 2013
- Subjects: Prose poems , Flash fiction , Short stories , English , Creative writing (Higher education) , Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century , South African poetry (English) -- 21st century , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5966 , http://hdl.handle.net/10962/d1001816
- Description: This collection of prose-poems and flash fiction, together with a few short stories, shows how romantic relationships colour our perspectives on the world. The collection has echoes throughout of speakers' voices, theme, imagery and tone. There is a narrative logic too, but working on a subtle level of echo and resonance
- Full Text:
The African Peer Review Mechanism : towards Africa's governance audit
- Authors: Molete, Nathan Teboho
- Date: 2008
- Subjects: African Peer Review Mechanism New Partnership for Africa's Development Peer review -- Africa Auditing -- Africa Africa -- Politics and government -- 1960-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2867 , http://hdl.handle.net/10962/d1007681
- Description: The concept of accountability has grown to become an integral part of a broader political and socio-economic transformation. Closely associated to it is the concept of "auditing" which has established itself as a main driving force of accountability and a core means of delivering it. The extent of the rise and expansion of "auditing" has subsequently come to influence every aspect of modern life and this has led to a situation in which practices have had to adapt to the principles of "auditing" processes. Auditing has become prevalent in both the public and private spheres and this impact has far reaching consequences. The concept of "auditing" is evident in the African Peer Review Mechanism (APRM) and is central to its review process. This thesis focuses on the concept of "auditing" in order to illustrate how the APRM has borrowed and applied insights from other disciplinary practices so as to enhance an understanding of accountability and transparency as features of "good governance" and to explicate how these concepts are conceived within the framework of the New Partnership for Africa's Development (NEPAD). It also clarifies the relationship that exists between "peer review" and "auditing" and argues that rather than being considered as two poles marked by distance from each other "auditing" and "peer review" are closely related and mutually constitutive.
- Full Text:
- Authors: Molete, Nathan Teboho
- Date: 2008
- Subjects: African Peer Review Mechanism New Partnership for Africa's Development Peer review -- Africa Auditing -- Africa Africa -- Politics and government -- 1960-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2867 , http://hdl.handle.net/10962/d1007681
- Description: The concept of accountability has grown to become an integral part of a broader political and socio-economic transformation. Closely associated to it is the concept of "auditing" which has established itself as a main driving force of accountability and a core means of delivering it. The extent of the rise and expansion of "auditing" has subsequently come to influence every aspect of modern life and this has led to a situation in which practices have had to adapt to the principles of "auditing" processes. Auditing has become prevalent in both the public and private spheres and this impact has far reaching consequences. The concept of "auditing" is evident in the African Peer Review Mechanism (APRM) and is central to its review process. This thesis focuses on the concept of "auditing" in order to illustrate how the APRM has borrowed and applied insights from other disciplinary practices so as to enhance an understanding of accountability and transparency as features of "good governance" and to explicate how these concepts are conceived within the framework of the New Partnership for Africa's Development (NEPAD). It also clarifies the relationship that exists between "peer review" and "auditing" and argues that rather than being considered as two poles marked by distance from each other "auditing" and "peer review" are closely related and mutually constitutive.
- Full Text:
The biology of Acia lineatifrons (Naude) (Homoptera : Cicadellidae) on grapevines in the Western Cape
- Authors: Marais, Elleunorah
- Date: 1988
- Subjects: Homoptera
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5597 , http://hdl.handle.net/10962/d1002047
- Description: The leafhopper, Acia lineatifrons (Naude) was identified as a pest on grapevines near Tulbagh in 1978 and has since been reported on grapevines all over the South Western Cape. A. lineatifrons causes browning of the leaves which often results in the shedding of the discoloured leaves. Heavy defoliation before harvest can result in sunburn damage to the grapes, whilst premature leaf loss after harvest adversely affects the ripening of the canes and the accumulation of reserves. This project was aimed at obtaining basic information on the biology and population dynamics of A. lineatifrons as well as to identify priorities for future research. This information is needed to develop a reliable crop-linked predictive model, methods for monitoring pest populations as well as to develop efficient short- and long-term control measures and pest management strategies. The life cycle of A. lineatifrons was studied in the laboratory. At 26°C the mean incubation period of the eggs was nine to eleven days, the mean developmental period for the five nymphal instars was 15 days and the minimum pre-oviposition period five to ten days. This adds up to a mean generation time of 29 to 36 days at 26°C. At 20°C the mean nymphal development period was 25 days, confirming the strong influence of temperature on the development rate. Fecundity was determined in the laboratory as the number of nymphs produced per female. The mean of 8,5 nymphs per female recorded at 26°C is very low compared to that of other leafhopper species (see Appendix 2). The low fecundity measured was most likely due to sub-optimal environmental conditions in the laboratory, a reduction in the suitability of the host plant under these conditions and handling of the females. The seasonal occurrence of A. lineatifrons on grapevines was studied over three seasons. It was found that the leafhoppers overwinter in the adult stage on indigenous Rubus spp, and that they enter the vineyard from the end of October until the beginning of November. Peak populations occurred between the middle of February and the end of March after which the population declined steadily towards the end of the season as the vine leaves were shed. The sex ratio of the overwintering population on R. chrysocarpus was heavily female biased, possibly due to differential mortality of the sexes. During the growing season the sex ratio was slightly male biased and reached equality on several occasions, both on the Rubus and on the grapevines. The movement of A. lineatifrons between the Rubus and the grapevines was investigated, but no evidence of a directional migration from the Rubus to the grapevines was found. Furthermore, no evidence was found to indicate that morphologically distinct short- and long-distance fliers, as found in Cicadulina species by Rose (1972b), exist in the A. lineatifrons population. Host preference tests also showed that adult leafhoppers apparently have no significant preference for grapevines to Rubus or vice versa. It seems, therefore, that the leafhoppers' move onto the grapevines at the beginning of the growing season is not prompted by a host preference. Chaboussou (1971) suggested that certain organic fungicides may cause leafhopper outbreaks because they affect the suitability of the vines as host plants and alter leafhopper fecundity. The effect of Mikal-M (active ingredient Fosetyl AL/Mancozeb), a systemic dithiocarbanate fungicide, on A. lineatifrons was investigated. Laboratory experiments showed no significant effect on fecundity and leaf analysis of potted vines treated with Mikal-M indicated no significant difference in total leaf nitrogen compared to untreated control plants. However, the field experiment on the effect of Mikal-M on the population build-up of the leafhopper showed that significantly more leafhoppers occurred on the vines treated with Mikal-M than on those treated with a conventional inorganic fungicide, copper oxychloride. In view of the far-reaching implications this can have on the viticultural industry, further research on the effects of organic fungicides on leafhopper populations is recommended to confirm the generality of these results so that recommendations regarding the use of these fungicides may be made. The question as to why A. lineatifrons became a pest only recently was raised. Three possibilities were considered, namely (1) that A. lineatifrons is a species of tropical origin which moved down the continent and became established in the Western Cape only recently, (2) that is has been in the Western Cape at least as long as the grapevines, but required prolonged exposure to establish itself on the new host and (3) that is has been on the vines for some time, but was noticed only recently when outbreaks occurred. These outbreaks could have been caused by the introduction of organic fungicides or the depletion of natural enemies by insecticides used to control other insects in the vineyards. Due to the lack of evidence this question could not be answered conclusively. Other research priorities that were established are the development of methods for damage assessment and monitoring of leafhopper populations, determining if A. lineatifrons can transmit grapevine virusses, the development of an economic threshold level and the identification of natural enemies of A. lineatifrons to enable the development of efficient pest management strategies (Summary, p. 63-65)
- Full Text:
- Authors: Marais, Elleunorah
- Date: 1988
- Subjects: Homoptera
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5597 , http://hdl.handle.net/10962/d1002047
- Description: The leafhopper, Acia lineatifrons (Naude) was identified as a pest on grapevines near Tulbagh in 1978 and has since been reported on grapevines all over the South Western Cape. A. lineatifrons causes browning of the leaves which often results in the shedding of the discoloured leaves. Heavy defoliation before harvest can result in sunburn damage to the grapes, whilst premature leaf loss after harvest adversely affects the ripening of the canes and the accumulation of reserves. This project was aimed at obtaining basic information on the biology and population dynamics of A. lineatifrons as well as to identify priorities for future research. This information is needed to develop a reliable crop-linked predictive model, methods for monitoring pest populations as well as to develop efficient short- and long-term control measures and pest management strategies. The life cycle of A. lineatifrons was studied in the laboratory. At 26°C the mean incubation period of the eggs was nine to eleven days, the mean developmental period for the five nymphal instars was 15 days and the minimum pre-oviposition period five to ten days. This adds up to a mean generation time of 29 to 36 days at 26°C. At 20°C the mean nymphal development period was 25 days, confirming the strong influence of temperature on the development rate. Fecundity was determined in the laboratory as the number of nymphs produced per female. The mean of 8,5 nymphs per female recorded at 26°C is very low compared to that of other leafhopper species (see Appendix 2). The low fecundity measured was most likely due to sub-optimal environmental conditions in the laboratory, a reduction in the suitability of the host plant under these conditions and handling of the females. The seasonal occurrence of A. lineatifrons on grapevines was studied over three seasons. It was found that the leafhoppers overwinter in the adult stage on indigenous Rubus spp, and that they enter the vineyard from the end of October until the beginning of November. Peak populations occurred between the middle of February and the end of March after which the population declined steadily towards the end of the season as the vine leaves were shed. The sex ratio of the overwintering population on R. chrysocarpus was heavily female biased, possibly due to differential mortality of the sexes. During the growing season the sex ratio was slightly male biased and reached equality on several occasions, both on the Rubus and on the grapevines. The movement of A. lineatifrons between the Rubus and the grapevines was investigated, but no evidence of a directional migration from the Rubus to the grapevines was found. Furthermore, no evidence was found to indicate that morphologically distinct short- and long-distance fliers, as found in Cicadulina species by Rose (1972b), exist in the A. lineatifrons population. Host preference tests also showed that adult leafhoppers apparently have no significant preference for grapevines to Rubus or vice versa. It seems, therefore, that the leafhoppers' move onto the grapevines at the beginning of the growing season is not prompted by a host preference. Chaboussou (1971) suggested that certain organic fungicides may cause leafhopper outbreaks because they affect the suitability of the vines as host plants and alter leafhopper fecundity. The effect of Mikal-M (active ingredient Fosetyl AL/Mancozeb), a systemic dithiocarbanate fungicide, on A. lineatifrons was investigated. Laboratory experiments showed no significant effect on fecundity and leaf analysis of potted vines treated with Mikal-M indicated no significant difference in total leaf nitrogen compared to untreated control plants. However, the field experiment on the effect of Mikal-M on the population build-up of the leafhopper showed that significantly more leafhoppers occurred on the vines treated with Mikal-M than on those treated with a conventional inorganic fungicide, copper oxychloride. In view of the far-reaching implications this can have on the viticultural industry, further research on the effects of organic fungicides on leafhopper populations is recommended to confirm the generality of these results so that recommendations regarding the use of these fungicides may be made. The question as to why A. lineatifrons became a pest only recently was raised. Three possibilities were considered, namely (1) that A. lineatifrons is a species of tropical origin which moved down the continent and became established in the Western Cape only recently, (2) that is has been in the Western Cape at least as long as the grapevines, but required prolonged exposure to establish itself on the new host and (3) that is has been on the vines for some time, but was noticed only recently when outbreaks occurred. These outbreaks could have been caused by the introduction of organic fungicides or the depletion of natural enemies by insecticides used to control other insects in the vineyards. Due to the lack of evidence this question could not be answered conclusively. Other research priorities that were established are the development of methods for damage assessment and monitoring of leafhopper populations, determining if A. lineatifrons can transmit grapevine virusses, the development of an economic threshold level and the identification of natural enemies of A. lineatifrons to enable the development of efficient pest management strategies (Summary, p. 63-65)
- Full Text:
The origins, growth and development of the Bantu Presbyterian Church of South Africa
- Authors: Van der Spuy, Daniel
- Date: 1971
- Subjects: Bantu Presbyterian Church of South Africa -- History
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1230 , http://hdl.handle.net/10962/d1007287
- Description: From Preface: "The function of the historian is neither to love the past nor to emancipate himself from the past, but to master and understand it as the key to understanding the present." (E.H. Carr, What is history?, 1964 p.26.) The existence of an independent Bantu Presbyterian Church (B.P.C.) has raised many questions and problems which could only be probed by tracing its history. It is fascinating that even with the passing of so many years the issues at stake are still in the forefront. Perhaps in understanding the past one may better understand the present, but only one with acute vision will know the "right solution". The "Presbyterian mission" has been one of many in South Africa and has been present for over 150 years, yet I found little, as far as published work is concerned, which deals comprehensively with the various bodies comprising this mission. Nor is it clear, even in Presbyterian circles, what its history and policy has been, or meant, in the life of this country. Unfortunately, material is not always readily available, (which I found to my dismay), and both time and expense is involved in collecting such. I have consequently had to rely on scanty information as well as the dry-as-dust, uninformative blue books of the B.P.C.and P.C.S.A., which may indicate trends but very little by way of individual thought. With some spadework done by a few, it is an ardent hope that more will be done to uncover the past to knit the Presbyterian tradition together, that it may take its place amongst other histories, not in any partisan manner, but only to contribute to a healthy ecumenical climate where the worth of each tradition is acknowledged and used to increase the spirit of closer co-operation. The question of Presbyterian Union has long been present. My hope is that this thesis may clarify and encourage.
- Full Text:
- Authors: Van der Spuy, Daniel
- Date: 1971
- Subjects: Bantu Presbyterian Church of South Africa -- History
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1230 , http://hdl.handle.net/10962/d1007287
- Description: From Preface: "The function of the historian is neither to love the past nor to emancipate himself from the past, but to master and understand it as the key to understanding the present." (E.H. Carr, What is history?, 1964 p.26.) The existence of an independent Bantu Presbyterian Church (B.P.C.) has raised many questions and problems which could only be probed by tracing its history. It is fascinating that even with the passing of so many years the issues at stake are still in the forefront. Perhaps in understanding the past one may better understand the present, but only one with acute vision will know the "right solution". The "Presbyterian mission" has been one of many in South Africa and has been present for over 150 years, yet I found little, as far as published work is concerned, which deals comprehensively with the various bodies comprising this mission. Nor is it clear, even in Presbyterian circles, what its history and policy has been, or meant, in the life of this country. Unfortunately, material is not always readily available, (which I found to my dismay), and both time and expense is involved in collecting such. I have consequently had to rely on scanty information as well as the dry-as-dust, uninformative blue books of the B.P.C.and P.C.S.A., which may indicate trends but very little by way of individual thought. With some spadework done by a few, it is an ardent hope that more will be done to uncover the past to knit the Presbyterian tradition together, that it may take its place amongst other histories, not in any partisan manner, but only to contribute to a healthy ecumenical climate where the worth of each tradition is acknowledged and used to increase the spirit of closer co-operation. The question of Presbyterian Union has long been present. My hope is that this thesis may clarify and encourage.
- Full Text:
A study of cation exchange in South African soils
- Authors: Du Toit, A A
- Date: 1952
- Subjects: Soil chemistry , Ion exchange
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4462 , http://hdl.handle.net/10962/d1011506 , Soil chemistry , Ion exchange
- Description: The colloidal fraction is the vital part of a soil. These extremely minute particles determine the nature of the soil and are mainly responsible for its many and varied functions. The most important of these functions is perhaps the ability of the colloids to adsorb and exchange cations, the elements so essential to all organisms as building materials. When pure water is passed through a non-saline. soil, the leachate will contain very few dissolved cations. If, on the other hand, an electrolyte such as a weak solution of sodiun chloride, is passed through the same soil, the leachate will contain considerable quantities of calcium, magnesium and potassiun chlorides as well as much of the original sodium chloride. The number of equivalents of the cations collected will be approximately the same as the number of equivalents of sodium ions added. Sodium ions have displaced some of the calcian, magnesium and potassium ions from the soil. This phenomenon is known as cation exchange. Intro., p. 1.
- Full Text:
- Authors: Du Toit, A A
- Date: 1952
- Subjects: Soil chemistry , Ion exchange
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4462 , http://hdl.handle.net/10962/d1011506 , Soil chemistry , Ion exchange
- Description: The colloidal fraction is the vital part of a soil. These extremely minute particles determine the nature of the soil and are mainly responsible for its many and varied functions. The most important of these functions is perhaps the ability of the colloids to adsorb and exchange cations, the elements so essential to all organisms as building materials. When pure water is passed through a non-saline. soil, the leachate will contain very few dissolved cations. If, on the other hand, an electrolyte such as a weak solution of sodiun chloride, is passed through the same soil, the leachate will contain considerable quantities of calcium, magnesium and potassiun chlorides as well as much of the original sodium chloride. The number of equivalents of the cations collected will be approximately the same as the number of equivalents of sodium ions added. Sodium ions have displaced some of the calcian, magnesium and potassium ions from the soil. This phenomenon is known as cation exchange. Intro., p. 1.
- Full Text:
A measuring device in spelling
- Authors: Knipe, V H
- Date: 1949
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:21161 , http://hdl.handle.net/10962/6650
- Full Text:
- Authors: Knipe, V H
- Date: 1949
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:21161 , http://hdl.handle.net/10962/6650
- Full Text:
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