Composition and phenology of insect pests of Capsicum (Solanaceae) cultivated in the Makana District, Eastern Cape Province, South Africa
- Authors: Hepburn, Colleen
- Date: 2008
- Subjects: Insects -- South Africa -- Eastern Cape -- Composition Insects -- South Africa -- Eastern Cape -- Phenology Agricultural pests -- South Africa -- Eastern Cape Peppers -- Diseases and pests -- South Africa -- Eastern Cape Solanaceae -- Diseases and pests -- South Africa -- Eastern Cape Insect pests -- South Africa -- Eastern Cape Insect pests -- Biological control -- South Africa -- Eastern Cape Insect pests -- Control -- Methods -- South Africa -- Eastern Cape Insects -- Host plants -- South Africa -- Eastern Cape Insect-plant relationships -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5656 , http://hdl.handle.net/10962/d1005339
- Description: Capsicum baccatum var. pendulum was first grown in the Makana District in 2005. Extremely little was known about best practices for cultivation or the insects and diseases associated with the crop in this area. The study was conducted during the second year of production, November 2005 and November 2006, in an attempt to identify the composition and phenology of insects occurring on C. baccatum. In the more rural parts of the Eastern Cape, and more particularly in Grahamstown, there are very few industries. With the advent of this new agricultural venture, a processing factory has been opened in Grahamstown creating more than 600 seasonal jobs in the factory and 1000 seasonal jobs on farms for local people. This business enterprise has not only brought about the creation of jobs, but also training and skills development and empowerment, generating much-needed income in this area. An extensive literature review yielded limited information on insect pests associated with Capsicum. Data from a pilot sampling trial undertaken were statistically analyzed to establish the number of plants to be scouted per site and the most effective scouting techniques to use. Based on the data available and insects collected during the pilot sampling trial, a surveillance programme was designed. Five different types of monitoring traps were placed in each of the eight study sites. Collection of trap catches and scouting of fifteen individual plants per site was undertaken on a weekly basis over the 52-week study period. The most commonly occurring potential insect pests were African Bollworm Helicoverpa armigera (Hübner), False Codling Moth Thaumatotibia leucotreta (= Cryptophlebia leucotreta) (Meyrick), Mediterranean Fruit Fly Ceratitis capitata (Wiedemann) and several species of thrips. Population densities of these pests and their phenology on Capsicum were determined. Statistical analyses established the efficacy of the monitoring traps for each pest, tested for differences among and between study sites, calculated an estimate of the number of pods damaged and a measure of plant damage.The results show that the majority of damage caused to the Capsicum baccatum cropping system was due to Mediterranean Fruit Fly populations. It was established that, although African Bollworm and False Codling Moth were present during the study period, their numbers were negligible and only nominal damage was caused by these pests. Damage caused by thrips species was apparent but not quantifiable. Intervention strategies using an Integrated Pest Management approach, are discussed.
- Full Text:
- Date Issued: 2008
- Authors: Hepburn, Colleen
- Date: 2008
- Subjects: Insects -- South Africa -- Eastern Cape -- Composition Insects -- South Africa -- Eastern Cape -- Phenology Agricultural pests -- South Africa -- Eastern Cape Peppers -- Diseases and pests -- South Africa -- Eastern Cape Solanaceae -- Diseases and pests -- South Africa -- Eastern Cape Insect pests -- South Africa -- Eastern Cape Insect pests -- Biological control -- South Africa -- Eastern Cape Insect pests -- Control -- Methods -- South Africa -- Eastern Cape Insects -- Host plants -- South Africa -- Eastern Cape Insect-plant relationships -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5656 , http://hdl.handle.net/10962/d1005339
- Description: Capsicum baccatum var. pendulum was first grown in the Makana District in 2005. Extremely little was known about best practices for cultivation or the insects and diseases associated with the crop in this area. The study was conducted during the second year of production, November 2005 and November 2006, in an attempt to identify the composition and phenology of insects occurring on C. baccatum. In the more rural parts of the Eastern Cape, and more particularly in Grahamstown, there are very few industries. With the advent of this new agricultural venture, a processing factory has been opened in Grahamstown creating more than 600 seasonal jobs in the factory and 1000 seasonal jobs on farms for local people. This business enterprise has not only brought about the creation of jobs, but also training and skills development and empowerment, generating much-needed income in this area. An extensive literature review yielded limited information on insect pests associated with Capsicum. Data from a pilot sampling trial undertaken were statistically analyzed to establish the number of plants to be scouted per site and the most effective scouting techniques to use. Based on the data available and insects collected during the pilot sampling trial, a surveillance programme was designed. Five different types of monitoring traps were placed in each of the eight study sites. Collection of trap catches and scouting of fifteen individual plants per site was undertaken on a weekly basis over the 52-week study period. The most commonly occurring potential insect pests were African Bollworm Helicoverpa armigera (Hübner), False Codling Moth Thaumatotibia leucotreta (= Cryptophlebia leucotreta) (Meyrick), Mediterranean Fruit Fly Ceratitis capitata (Wiedemann) and several species of thrips. Population densities of these pests and their phenology on Capsicum were determined. Statistical analyses established the efficacy of the monitoring traps for each pest, tested for differences among and between study sites, calculated an estimate of the number of pods damaged and a measure of plant damage.The results show that the majority of damage caused to the Capsicum baccatum cropping system was due to Mediterranean Fruit Fly populations. It was established that, although African Bollworm and False Codling Moth were present during the study period, their numbers were negligible and only nominal damage was caused by these pests. Damage caused by thrips species was apparent but not quantifiable. Intervention strategies using an Integrated Pest Management approach, are discussed.
- Full Text:
- Date Issued: 2008
Importance of various data sources in deterministic stock assessment models
- Authors: Northrop, Amanda Rosalind
- Date: 2008
- Subjects: Fish stock assessment -- Mathematical models , Fishery management -- Mathematical models , Fish populations -- Mathematical models , Error analysis (Mathematics) , Fishery management -- Statistical methods , Fish stock assessment -- Statistical methods
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5571 , http://hdl.handle.net/10962/d1002811 , Fish stock assessment -- Mathematical models , Fishery management -- Mathematical models , Fish populations -- Mathematical models , Error analysis (Mathematics) , Fishery management -- Statistical methods , Fish stock assessment -- Statistical methods
- Description: In fisheries, advice for the management of fish populations is based upon management quantities that are estimated by stock assessment models. Fisheries stock assessment is a process in which data collected from a fish population are used to generate a model which enables the effects of fishing on a stock to be quantified. This study determined the effects of various data sources, assumptions, error scenarios and sample sizes on the accuracy with which the age-structured production model and the Schaefer model (assessment models) were able to estimate key management quantities for a fish resource similar to the Cape hakes (Merluccius capensis and M. paradoxus). An age-structured production model was used as the operating model to simulate hypothetical fish resource population dynamics for which management quantities could be determined by the assessment models. Different stocks were simulated with various harvest rate histories. These harvest rates produced Downhill trip data, where harvest rates increase over time until the resource is close to collapse, and Good contrast data, where the harvest rate increases over time until the resource is at less than half of it’s exploitable biomass, and then it decreases allowing the resource to rebuild. The accuracy of the assessment models were determined when data were drawn from the operating model with various combinations of error. The age-structured production model was more accurate at estimating maximum sustainable yield, maximum sustainable yield level and the maximum sustainable yield ratio. The Schaefer model gave more accurate estimates of Depletion and Total Allowable Catch. While the assessment models were able to estimate management quantities using Downhill trip data, the estimates improved significantly when the models were tuned with Good contrast data. When autocorrelation in the spawner-recruit curve was not accounted for by the deterministic assessment model, inaccuracy in parameter estimates were high. The assessment model management quantities were not greatly affected by multinomial ageing error in the catch-at-age matrices at a sample size of 5000 otoliths. Assessment model estimates were closer to their true values when log-normal error were assumed in the catch-at-age matrix, even when the true underlying error were multinomial. However, the multinomial had smaller coefficients of variation at all sample sizes, between 1000 and 10000, of otoliths aged. It was recommended that the assessment model is chosen based on the management quantity of interest. When the underlying error is multinomial, the weighted log-normal likelihood function should be used in the catch-at-age matrix to obtain accurate parameter estimates. However, the multinomial likelihood should be used to minimise the coefficient of variation. Investigation into correcting for autocorrelation in the stock-recruitment relationship should be carried out, as it had a large effect on the accuracy of management quantities.
- Full Text:
- Date Issued: 2008
- Authors: Northrop, Amanda Rosalind
- Date: 2008
- Subjects: Fish stock assessment -- Mathematical models , Fishery management -- Mathematical models , Fish populations -- Mathematical models , Error analysis (Mathematics) , Fishery management -- Statistical methods , Fish stock assessment -- Statistical methods
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5571 , http://hdl.handle.net/10962/d1002811 , Fish stock assessment -- Mathematical models , Fishery management -- Mathematical models , Fish populations -- Mathematical models , Error analysis (Mathematics) , Fishery management -- Statistical methods , Fish stock assessment -- Statistical methods
- Description: In fisheries, advice for the management of fish populations is based upon management quantities that are estimated by stock assessment models. Fisheries stock assessment is a process in which data collected from a fish population are used to generate a model which enables the effects of fishing on a stock to be quantified. This study determined the effects of various data sources, assumptions, error scenarios and sample sizes on the accuracy with which the age-structured production model and the Schaefer model (assessment models) were able to estimate key management quantities for a fish resource similar to the Cape hakes (Merluccius capensis and M. paradoxus). An age-structured production model was used as the operating model to simulate hypothetical fish resource population dynamics for which management quantities could be determined by the assessment models. Different stocks were simulated with various harvest rate histories. These harvest rates produced Downhill trip data, where harvest rates increase over time until the resource is close to collapse, and Good contrast data, where the harvest rate increases over time until the resource is at less than half of it’s exploitable biomass, and then it decreases allowing the resource to rebuild. The accuracy of the assessment models were determined when data were drawn from the operating model with various combinations of error. The age-structured production model was more accurate at estimating maximum sustainable yield, maximum sustainable yield level and the maximum sustainable yield ratio. The Schaefer model gave more accurate estimates of Depletion and Total Allowable Catch. While the assessment models were able to estimate management quantities using Downhill trip data, the estimates improved significantly when the models were tuned with Good contrast data. When autocorrelation in the spawner-recruit curve was not accounted for by the deterministic assessment model, inaccuracy in parameter estimates were high. The assessment model management quantities were not greatly affected by multinomial ageing error in the catch-at-age matrices at a sample size of 5000 otoliths. Assessment model estimates were closer to their true values when log-normal error were assumed in the catch-at-age matrix, even when the true underlying error were multinomial. However, the multinomial had smaller coefficients of variation at all sample sizes, between 1000 and 10000, of otoliths aged. It was recommended that the assessment model is chosen based on the management quantity of interest. When the underlying error is multinomial, the weighted log-normal likelihood function should be used in the catch-at-age matrix to obtain accurate parameter estimates. However, the multinomial likelihood should be used to minimise the coefficient of variation. Investigation into correcting for autocorrelation in the stock-recruitment relationship should be carried out, as it had a large effect on the accuracy of management quantities.
- Full Text:
- Date Issued: 2008
A critical edition of the poems of Henry Vaux (c. 1559-1587) in MS. Folger Bd with STC 22957
- Hacksley, Timothy Christopher
- Authors: Hacksley, Timothy Christopher
- Date: 2008
- Subjects: Vaux, Henry, ca. 1559-1587 -- Criticism and interpretation Vaux, Henry, ca. 1559-1587 Latin poetry, Medieval and modern -- History and criticism English poetry -- Early modern, 1500-1700
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2200 , http://hdl.handle.net/10962/d1002242
- Description: This thesis offers an edition of the English and Latin poems found in MS. Folger bd with STC 22957, attributed to Henry Vaux (c. 1559—1587), a recusant, priest-smuggler, and child prodigy. THE TEXT of the edition is preceded by an introduction comprising three parts: a GENERAL INTRODUCTION describing Vaux‘s socio-historical and biographical context; a CRITICAL INTRODUCTION describing the Medieval and Early Modern literary contexts of Vaux‘s poems and the forms, traditions, topoi, and conventions adhered to in them; and a TEXTUAL INTRODUCTION describing the seventeenth-century manuscript copy of the poems used as the source text and explaining and justifying the editorial decisions made. Textual variants and instances of doubtful authorship are also discussed. THE TEXT itself is presented in the original spelling of the MS. and is a diplomatic edition: the scribe‘s use of characters that are now defunct (such as long ‗s‘ and ‗=‘ for ‗-‘) has not been modernised. A critical apparatus is provided with THE TEXT. THE TEXT is followed by an extensive COMMENTARY, which glosses un-usual or archaic words and phrases, points out allusions and their likely sources, discusses literary forms and conventions which inform the reading of the po-ems, and observes peculiarities in poetic metre. Translations and commentary are offered for Vaux‘s Latin poems. The five appendices following the COMMEN-TARY comprise a MODERNISED TEXT of the poems, a FACSIMILE OF THE FOLGER MS., a SUBSEQUENT HISTORY OF THE VAUX FAMILY after Henry Vaux‘s death, a text JOHN OF PECHAM‘S PHILOMENA PRAEVIA (a text which informs the reading of Vaux‘s ―A complaint to the Nightingale‖) along with a parallel translation by me, and transcriptions of TEXTUAL VARIANTS. A BIBLIOGRAPHY of works cited, re-ferred to or consulted follows the appendices. A comprehensive GENERAL INDEX of subjects, people, places, and literary works and forms follows this, and an IN-DEX OF FIRST LINES AND TITLES of Vaux‘s poems completes the edition.
- Full Text:
- Date Issued: 2008
- Authors: Hacksley, Timothy Christopher
- Date: 2008
- Subjects: Vaux, Henry, ca. 1559-1587 -- Criticism and interpretation Vaux, Henry, ca. 1559-1587 Latin poetry, Medieval and modern -- History and criticism English poetry -- Early modern, 1500-1700
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2200 , http://hdl.handle.net/10962/d1002242
- Description: This thesis offers an edition of the English and Latin poems found in MS. Folger bd with STC 22957, attributed to Henry Vaux (c. 1559—1587), a recusant, priest-smuggler, and child prodigy. THE TEXT of the edition is preceded by an introduction comprising three parts: a GENERAL INTRODUCTION describing Vaux‘s socio-historical and biographical context; a CRITICAL INTRODUCTION describing the Medieval and Early Modern literary contexts of Vaux‘s poems and the forms, traditions, topoi, and conventions adhered to in them; and a TEXTUAL INTRODUCTION describing the seventeenth-century manuscript copy of the poems used as the source text and explaining and justifying the editorial decisions made. Textual variants and instances of doubtful authorship are also discussed. THE TEXT itself is presented in the original spelling of the MS. and is a diplomatic edition: the scribe‘s use of characters that are now defunct (such as long ‗s‘ and ‗=‘ for ‗-‘) has not been modernised. A critical apparatus is provided with THE TEXT. THE TEXT is followed by an extensive COMMENTARY, which glosses un-usual or archaic words and phrases, points out allusions and their likely sources, discusses literary forms and conventions which inform the reading of the po-ems, and observes peculiarities in poetic metre. Translations and commentary are offered for Vaux‘s Latin poems. The five appendices following the COMMEN-TARY comprise a MODERNISED TEXT of the poems, a FACSIMILE OF THE FOLGER MS., a SUBSEQUENT HISTORY OF THE VAUX FAMILY after Henry Vaux‘s death, a text JOHN OF PECHAM‘S PHILOMENA PRAEVIA (a text which informs the reading of Vaux‘s ―A complaint to the Nightingale‖) along with a parallel translation by me, and transcriptions of TEXTUAL VARIANTS. A BIBLIOGRAPHY of works cited, re-ferred to or consulted follows the appendices. A comprehensive GENERAL INDEX of subjects, people, places, and literary works and forms follows this, and an IN-DEX OF FIRST LINES AND TITLES of Vaux‘s poems completes the edition.
- Full Text:
- Date Issued: 2008
Teaching reading in grade 4 Namibian classrooms : a case study
- Authors: Mutenda, Josephine
- Date: 2008
- Subjects: Literacy -- Study and teaching (Elementary) -- Namibia English language -- Study and teaching (Elementary) -- Namibia Reading (Elementary) -- Namibia Second language acquisition
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1797 , http://hdl.handle.net/10962/d1003682
- Description: Literacy is currently a topic of great concern in Namibia. Learners in this country have difficulty in reading and writing, and are often functionally illiterate. This study focuses on the beliefs, experiences and practices of teachers of reading in English to second language learners in Grade 4. Grade 4 is the transitional grade from mother tongue to English as the medium of instruction. The switch to English makes teaching reading in that language especially challenging. The study is structured according to the case study mode of enquiry, with the target respondents comprising Grade 4 teachers. Classroom observation, interviews and document analysis were used as means of collecting data. The main findings revealed that beliefs and experience had an impact on the way in which reading was taught in this study. It emerged that the teachers’ childhood experiences of literacy and learning to read are perpetuated in their beliefs, their attitudes, their basic conceptualization of reading and their current practices, all of which directly affect the children in their classes. Although the teachers’ professional training also had some influence on their teaching methods, neither of the two teachers interviewed had received much in-service support on how to teach reading, and they depended to a large extent on their recall of how they had learned to read themselves. Both teachers were taught in a traditional, teacher-centered way, involving phonics, rote-learning and drilling. Because they see themselves as competent readers, they believe that these approaches were effective and worth sustaining. Tentative recommendations arising from analysis of the data indicate possible areas for improvement in the teaching of reading, and offer guidelines to help teachers cope with the challenge.
- Full Text:
- Date Issued: 2008
- Authors: Mutenda, Josephine
- Date: 2008
- Subjects: Literacy -- Study and teaching (Elementary) -- Namibia English language -- Study and teaching (Elementary) -- Namibia Reading (Elementary) -- Namibia Second language acquisition
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1797 , http://hdl.handle.net/10962/d1003682
- Description: Literacy is currently a topic of great concern in Namibia. Learners in this country have difficulty in reading and writing, and are often functionally illiterate. This study focuses on the beliefs, experiences and practices of teachers of reading in English to second language learners in Grade 4. Grade 4 is the transitional grade from mother tongue to English as the medium of instruction. The switch to English makes teaching reading in that language especially challenging. The study is structured according to the case study mode of enquiry, with the target respondents comprising Grade 4 teachers. Classroom observation, interviews and document analysis were used as means of collecting data. The main findings revealed that beliefs and experience had an impact on the way in which reading was taught in this study. It emerged that the teachers’ childhood experiences of literacy and learning to read are perpetuated in their beliefs, their attitudes, their basic conceptualization of reading and their current practices, all of which directly affect the children in their classes. Although the teachers’ professional training also had some influence on their teaching methods, neither of the two teachers interviewed had received much in-service support on how to teach reading, and they depended to a large extent on their recall of how they had learned to read themselves. Both teachers were taught in a traditional, teacher-centered way, involving phonics, rote-learning and drilling. Because they see themselves as competent readers, they believe that these approaches were effective and worth sustaining. Tentative recommendations arising from analysis of the data indicate possible areas for improvement in the teaching of reading, and offer guidelines to help teachers cope with the challenge.
- Full Text:
- Date Issued: 2008
The development and evaluation of a custom-built synchronous online learning environment for tertiary education in South Africa
- Authors: Halse, Michelle Louise
- Date: 2008 , 2008-02-23
- Subjects: Education, Higher -- South Africa -- Computer-assisted instruction , Universities and colleges -- Computer networks -- South Africa , Internet in higher education -- South Africa , Distance education -- South Africa -- Computer-assisted instruction , Computer-assisted instruction -- South Africa , Computer science -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4636 , http://hdl.handle.net/10962/d1006545 , Education, Higher -- South Africa -- Computer-assisted instruction , Universities and colleges -- Computer networks -- South Africa , Internet in higher education -- South Africa , Distance education -- South Africa -- Computer-assisted instruction , Computer-assisted instruction -- South Africa , Computer science -- Study and teaching (Higher) -- South Africa
- Description: The Departments of Computer Science and Information Systems at Rhodes University currently share certain honours-level (fourth year) course modules with students from the corresponding departments at the previously disadvantaged University of Fort Hare. These lectures are currently delivered using video-conferencing. This was found to present a number of problems including challenges in terms of implementing desired pedagogical approaches, inequitable learning experiences, student disengagement at the remote venue, and inflexibility of the video-conferencing system. In order to address these problems, various e-learning modes were investigated and synchronous e-learning were found to offer a number of advantages over asynchronous e-learning. Live Virtual Classrooms (LVCs) were identified as synchronous e-learning tools that support the pedagogical principles important to the two universities and to the broader context of South African tertiary education, and commercial LVC applications were investigated and evaluated. Informed by the results of this investigation a small, simple LVC was designed, developed and customised for use in a predominantly academic sphere and deployment in a South African tertiary educational context. Testing and evaluation of this solution was carried out and the results analysed in terms of the LVC’s technical merits and the pedagogical value of the solution as experienced by students and lecturers/facilitators. An evaluation of this solution indicated that the LVC solves a number of the identified problems with video-conferencing and also provides a flexible/customisable/extensible solution that supports highly interactive, collaborative, learner-centred education. The custom LVC solution could be easily adapted to the specific needs of any tertiary educational institute in the country, and results may benefit other tertiary educational institutions involved in or dependant on distance learning.
- Full Text:
- Date Issued: 2008
- Authors: Halse, Michelle Louise
- Date: 2008 , 2008-02-23
- Subjects: Education, Higher -- South Africa -- Computer-assisted instruction , Universities and colleges -- Computer networks -- South Africa , Internet in higher education -- South Africa , Distance education -- South Africa -- Computer-assisted instruction , Computer-assisted instruction -- South Africa , Computer science -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4636 , http://hdl.handle.net/10962/d1006545 , Education, Higher -- South Africa -- Computer-assisted instruction , Universities and colleges -- Computer networks -- South Africa , Internet in higher education -- South Africa , Distance education -- South Africa -- Computer-assisted instruction , Computer-assisted instruction -- South Africa , Computer science -- Study and teaching (Higher) -- South Africa
- Description: The Departments of Computer Science and Information Systems at Rhodes University currently share certain honours-level (fourth year) course modules with students from the corresponding departments at the previously disadvantaged University of Fort Hare. These lectures are currently delivered using video-conferencing. This was found to present a number of problems including challenges in terms of implementing desired pedagogical approaches, inequitable learning experiences, student disengagement at the remote venue, and inflexibility of the video-conferencing system. In order to address these problems, various e-learning modes were investigated and synchronous e-learning were found to offer a number of advantages over asynchronous e-learning. Live Virtual Classrooms (LVCs) were identified as synchronous e-learning tools that support the pedagogical principles important to the two universities and to the broader context of South African tertiary education, and commercial LVC applications were investigated and evaluated. Informed by the results of this investigation a small, simple LVC was designed, developed and customised for use in a predominantly academic sphere and deployment in a South African tertiary educational context. Testing and evaluation of this solution was carried out and the results analysed in terms of the LVC’s technical merits and the pedagogical value of the solution as experienced by students and lecturers/facilitators. An evaluation of this solution indicated that the LVC solves a number of the identified problems with video-conferencing and also provides a flexible/customisable/extensible solution that supports highly interactive, collaborative, learner-centred education. The custom LVC solution could be easily adapted to the specific needs of any tertiary educational institute in the country, and results may benefit other tertiary educational institutions involved in or dependant on distance learning.
- Full Text:
- Date Issued: 2008
Biosorption of precious metals from synthetic and refinery wastewaters by immobilized saccharomyces cerevisiae
- Authors: Mack, Cherie-Lynn
- Date: 2008
- Subjects: Metals -- Refining Metals -- Absorption and adsorption Saccharomyces cerevisiae Factory and trade waste Water reuse Platinum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4071 , http://hdl.handle.net/10962/d1006977
- Description: The process of precious metal refining can be up to 99.99% efficient at best, and although it may seem small, the amount of valuable metal lost to waste streams is appreciable enough to warrant recovery. The method currently used to remove entrained metal ions from refinery wastewaters, chemical precipitation, is not an effective means for selective recovery of precious metals from a wastewater. Biosorption, the ability of certain types of biomass to bind and concentrate metals from even very dilute aqueous solutions, may be an effective point-source metal recovery strategy. The yeast, Saccharomyces cerevisiae, has been found capable of sorbing numerous precious and base metals, and is a cheap and abundant source of biomass. As such, it represents a possible precious metal sorbent for application to refining wastewaters. In this investigation, S. cerevisiae biomass was immobilized, using polyethyleneimine and glutaraldehyde, to produce a suitable sorbent, which was found to be capable of high platinum uptake (150 to 170 mg/g) at low pH (< 2). The sorption mechanism was elucidated and found to be a chemical reaction, which made effective desorption impossible. The sorption process was investigated in a packed bed column conformation, the results of which showed that the diameter and height of the column require further optimization in order to attain the metal uptake values achieved in the batch studies. When applied to a refinery wastewater, two key wastewater characteristics limited the success of the sorption process; the high inorganic ion content and the complex speciation of the platinum ions. The results proved the concept principle of platinum recovery by immobilized yeast biosorption and indicated that a more detailed understanding of the platinum speciation within the wastewater is required before the biosorption process can be applied. Overall, the sorption of platinum by the S. cerevisiae sorbent was demonstrated to be highly effective in principle, but the complexity of the wastewater requires that pretreatment steps be taken before the successful application of this process to an industrial wastewater.
- Full Text:
- Date Issued: 2008
- Authors: Mack, Cherie-Lynn
- Date: 2008
- Subjects: Metals -- Refining Metals -- Absorption and adsorption Saccharomyces cerevisiae Factory and trade waste Water reuse Platinum
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4071 , http://hdl.handle.net/10962/d1006977
- Description: The process of precious metal refining can be up to 99.99% efficient at best, and although it may seem small, the amount of valuable metal lost to waste streams is appreciable enough to warrant recovery. The method currently used to remove entrained metal ions from refinery wastewaters, chemical precipitation, is not an effective means for selective recovery of precious metals from a wastewater. Biosorption, the ability of certain types of biomass to bind and concentrate metals from even very dilute aqueous solutions, may be an effective point-source metal recovery strategy. The yeast, Saccharomyces cerevisiae, has been found capable of sorbing numerous precious and base metals, and is a cheap and abundant source of biomass. As such, it represents a possible precious metal sorbent for application to refining wastewaters. In this investigation, S. cerevisiae biomass was immobilized, using polyethyleneimine and glutaraldehyde, to produce a suitable sorbent, which was found to be capable of high platinum uptake (150 to 170 mg/g) at low pH (< 2). The sorption mechanism was elucidated and found to be a chemical reaction, which made effective desorption impossible. The sorption process was investigated in a packed bed column conformation, the results of which showed that the diameter and height of the column require further optimization in order to attain the metal uptake values achieved in the batch studies. When applied to a refinery wastewater, two key wastewater characteristics limited the success of the sorption process; the high inorganic ion content and the complex speciation of the platinum ions. The results proved the concept principle of platinum recovery by immobilized yeast biosorption and indicated that a more detailed understanding of the platinum speciation within the wastewater is required before the biosorption process can be applied. Overall, the sorption of platinum by the S. cerevisiae sorbent was demonstrated to be highly effective in principle, but the complexity of the wastewater requires that pretreatment steps be taken before the successful application of this process to an industrial wastewater.
- Full Text:
- Date Issued: 2008
Commodity fetishism and domination: the contributions of Marx, Lukács, Horkheimer, Adorno and Bourdieu
- Authors: Lloyd, Gareth
- Date: 2008
- Subjects: Marx, Karl, 1818-1883 Lukács, György, 1885-1971 Horkheimer, Max, 1895-1973 Adorno, Theodor W., 1903-1969 Bourdieu, Pierre, 1930-2002 Commodity fetishism Capitalism Consumption (Economics) Marxian economics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2795 , http://hdl.handle.net/10962/d1003005
- Description: This thesis seeks to trace domination theory back to the influential work done by Marx on commodity fetishism. Marx's work proves to be an original account of domination that explains how the dominated many accept the rule of the privileged few. The theory of commodity fetishism develops the idea that individuals come to adopt beliefs that bolster and reproduce the status quo of capitalism. For Marx, the way that individuals experience capitalism is different from the way that it actually works because, in fact, lived experience is actually false. Oppression, inequality and exploitation are thus hidden and the main source of conflict between the oppressed many and the privileged few is obscured. I seek to develop this insight of Marx's into a more comprehensive account of how dominating capitalism self maintains. Lukács' theory of reification explains how capitalism has become all-embracing because capitalism has developed its own type of rationality. This specific rationality shapes thought, which in turn, generates false beliefs that favour the continuation of the status quo. Horkheimer and Adorno argue that capitalism extends its influence by means of its deep involvement in modern culture. Today, culture has become an massive industry which inculcates the logic and principles of capitalism into individuals. For these theorists, capitalism has penetrated all areas of life; experience, knowledge and thought have become extensions of capitalism itself. Marx, Lukács, Horkheimer and Adorno give accounts of how false beliefs are put into practice. Hence the importance of the work of Bourdieu. Bourdieu's theory of distinction describes how the status quo in capitalism is maintained by the behaviour of individuals through their daily acts of consumption. I argue that the consumption of commodities reproduces the status quo in two ways: firstly, establishing an upper-class which takes the lead in patterns of consumption, and, secondly, by creating a middle class that follows its example. Finally, I relate Bourdieu's insights to the theories of Marx, Lukács, Horkheimer and Adorno and Bourdieu in order to arrive at a more inclusive account of how.
- Full Text:
- Date Issued: 2008
- Authors: Lloyd, Gareth
- Date: 2008
- Subjects: Marx, Karl, 1818-1883 Lukács, György, 1885-1971 Horkheimer, Max, 1895-1973 Adorno, Theodor W., 1903-1969 Bourdieu, Pierre, 1930-2002 Commodity fetishism Capitalism Consumption (Economics) Marxian economics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2795 , http://hdl.handle.net/10962/d1003005
- Description: This thesis seeks to trace domination theory back to the influential work done by Marx on commodity fetishism. Marx's work proves to be an original account of domination that explains how the dominated many accept the rule of the privileged few. The theory of commodity fetishism develops the idea that individuals come to adopt beliefs that bolster and reproduce the status quo of capitalism. For Marx, the way that individuals experience capitalism is different from the way that it actually works because, in fact, lived experience is actually false. Oppression, inequality and exploitation are thus hidden and the main source of conflict between the oppressed many and the privileged few is obscured. I seek to develop this insight of Marx's into a more comprehensive account of how dominating capitalism self maintains. Lukács' theory of reification explains how capitalism has become all-embracing because capitalism has developed its own type of rationality. This specific rationality shapes thought, which in turn, generates false beliefs that favour the continuation of the status quo. Horkheimer and Adorno argue that capitalism extends its influence by means of its deep involvement in modern culture. Today, culture has become an massive industry which inculcates the logic and principles of capitalism into individuals. For these theorists, capitalism has penetrated all areas of life; experience, knowledge and thought have become extensions of capitalism itself. Marx, Lukács, Horkheimer and Adorno give accounts of how false beliefs are put into practice. Hence the importance of the work of Bourdieu. Bourdieu's theory of distinction describes how the status quo in capitalism is maintained by the behaviour of individuals through their daily acts of consumption. I argue that the consumption of commodities reproduces the status quo in two ways: firstly, establishing an upper-class which takes the lead in patterns of consumption, and, secondly, by creating a middle class that follows its example. Finally, I relate Bourdieu's insights to the theories of Marx, Lukács, Horkheimer and Adorno and Bourdieu in order to arrive at a more inclusive account of how.
- Full Text:
- Date Issued: 2008
A case for institutional investigations in economic research methods with reference to South Africa's agricultural sector
- Authors: Mbatha, Cyril
- Date: 2008
- Subjects: Economic development -- South Africa Economic development -- Research -- Methodology Agriculture -- South Africa Agriculture -- Economic aspects -- South Africa Agricultural productivity -- South Africa Agriculture -- Research -- South Africa South Africa -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:972 , http://hdl.handle.net/10962/d1002706
- Description: Economic development remains elusive for many world economies, but especially those of African countries. The current global inequalities in terms of GNP per capita and human living standards between developed and developing nations have ensured that the challenges of food insecurities are only some of the many negative experiences of underdevelopment in the African continent. Hence, delivery pressures are increasing on policy makers and researchers to provide tangible and timely economic solutions to the resilient state of underdevelopment. In the policy fights against the challenges posed by a lack of development in South Africa, the agricultural sector has in the past and continues in the present to play a central role. Such is the case because the majority of citizens rely on agricultural production activities for their livelihoods. For instance, even though the sector only contributed four percent towards the national Gross Domestic Product in 2006, in the Eastern Cape Province, more than seventy percent of the total population resided in rural areas. Moreover, in 2004 more than sixty percent of the national formal and informal employment levels were found in the sector. These economic indicators do not only reinforce the assertions that high levels of geographical and sectoral inequalities exist in the country’s economy, but they also illustrate the importance of the agricultural sector in public policy attempts, which are aimed at achieving food security alongside long-term developmental objectives. Some economists, especially the proponents of institutionalism, have argued that most of the recommendations to public policy interventions from mainstream economic research endeavours are not adequately helpful. The recommendations generally lack well considered and socially effective ideas, mainly because there remains some level of ignorance about the impacts that institutions have on economic and social systems. Some argue that this ignorance is reflected in (flawed) hedonistic and rationalist assumptions made about economic actors and in the methodological thinking of many research designs and economic analyses. The misuse of formal tools and statistical methods, for example, are some of the important factors, which have led to failures of the discipline of economics to provide effective policy solutions to problems of underdevelopment and poverty, especially in poor country environments. The thesis, having taken account of the majority of criticisms levelled against the classical and new-classical economic schools of thought, argues that the discipline as a whole lacks a paradigmatic integration of institutional and new-classical economic perspectives to offer appropriate guidelines for a methodology aimed at achieving socially responsive research outputs. The lack of this integration has resulted in a skewed selection of methods by economists, which are employed in research without a supportive and in-depth understanding of institutional and social factors. To support the thesis, a more effective and integrated framework for economic research is developed and presented with case study illustrations in a cumulative manner. The 20th century history of agricultural policies in South Africa, the agricultural and institutional case studies from the Eastern Cape Province alongside reviews of other agricultural studies are all used in presenting a case for rigorous institutional investigations in general economic research. These are also used in developing the proposed integrated framework, which aims to give guidance in developing research methods, which are more socially responsive. Having shown the usefulness of the proposed research framework, the thesis recommends that public policy interventions (at national and local levels) should aim to eliminate all types of institutions which have high associated transactional costs. The interventions should also encourage the emergence and growth of the types of institutions, which present the lowest costs to initiatives of economic development. In the primary case studies from the Eastern Cape Province, the insecurity of land tenure and the various local initiatives of business ventures are highlighted as two examples of the types of institutions, which respectively present high and low transactional costs to local initiatives of agricultural and economic development.
- Full Text:
- Date Issued: 2008
- Authors: Mbatha, Cyril
- Date: 2008
- Subjects: Economic development -- South Africa Economic development -- Research -- Methodology Agriculture -- South Africa Agriculture -- Economic aspects -- South Africa Agricultural productivity -- South Africa Agriculture -- Research -- South Africa South Africa -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:972 , http://hdl.handle.net/10962/d1002706
- Description: Economic development remains elusive for many world economies, but especially those of African countries. The current global inequalities in terms of GNP per capita and human living standards between developed and developing nations have ensured that the challenges of food insecurities are only some of the many negative experiences of underdevelopment in the African continent. Hence, delivery pressures are increasing on policy makers and researchers to provide tangible and timely economic solutions to the resilient state of underdevelopment. In the policy fights against the challenges posed by a lack of development in South Africa, the agricultural sector has in the past and continues in the present to play a central role. Such is the case because the majority of citizens rely on agricultural production activities for their livelihoods. For instance, even though the sector only contributed four percent towards the national Gross Domestic Product in 2006, in the Eastern Cape Province, more than seventy percent of the total population resided in rural areas. Moreover, in 2004 more than sixty percent of the national formal and informal employment levels were found in the sector. These economic indicators do not only reinforce the assertions that high levels of geographical and sectoral inequalities exist in the country’s economy, but they also illustrate the importance of the agricultural sector in public policy attempts, which are aimed at achieving food security alongside long-term developmental objectives. Some economists, especially the proponents of institutionalism, have argued that most of the recommendations to public policy interventions from mainstream economic research endeavours are not adequately helpful. The recommendations generally lack well considered and socially effective ideas, mainly because there remains some level of ignorance about the impacts that institutions have on economic and social systems. Some argue that this ignorance is reflected in (flawed) hedonistic and rationalist assumptions made about economic actors and in the methodological thinking of many research designs and economic analyses. The misuse of formal tools and statistical methods, for example, are some of the important factors, which have led to failures of the discipline of economics to provide effective policy solutions to problems of underdevelopment and poverty, especially in poor country environments. The thesis, having taken account of the majority of criticisms levelled against the classical and new-classical economic schools of thought, argues that the discipline as a whole lacks a paradigmatic integration of institutional and new-classical economic perspectives to offer appropriate guidelines for a methodology aimed at achieving socially responsive research outputs. The lack of this integration has resulted in a skewed selection of methods by economists, which are employed in research without a supportive and in-depth understanding of institutional and social factors. To support the thesis, a more effective and integrated framework for economic research is developed and presented with case study illustrations in a cumulative manner. The 20th century history of agricultural policies in South Africa, the agricultural and institutional case studies from the Eastern Cape Province alongside reviews of other agricultural studies are all used in presenting a case for rigorous institutional investigations in general economic research. These are also used in developing the proposed integrated framework, which aims to give guidance in developing research methods, which are more socially responsive. Having shown the usefulness of the proposed research framework, the thesis recommends that public policy interventions (at national and local levels) should aim to eliminate all types of institutions which have high associated transactional costs. The interventions should also encourage the emergence and growth of the types of institutions, which present the lowest costs to initiatives of economic development. In the primary case studies from the Eastern Cape Province, the insecurity of land tenure and the various local initiatives of business ventures are highlighted as two examples of the types of institutions, which respectively present high and low transactional costs to local initiatives of agricultural and economic development.
- Full Text:
- Date Issued: 2008
Stakeholders' perceptions of the shift to democratic leadership in a secondary school in the Eastern Cape : a case study
- Authors: Lombo, Mzimkhulu Solomon
- Date: 2008
- Subjects: Education -- South Africa -- Eastern Cape , Education and state -- South Africa -- Eastern Cape , Education -- Political aspects -- South Africa -- Eastern Cape , Education, Secondary -- South Africa -- Eastern Cape -- Case studies , Educational change -- South Africa -- Eastern Cape , Educational leadership -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2001 , http://hdl.handle.net/10962/d1015541
- Description: The advent of political democracy in South Africa in 1994 gave rise to new policy in education promoting democratic and participative ways of managing and leading schools. The intention was both to break from the apartheid past which was characterised by an authoritarian, nonparticipative mindset, as well as to point the way for future education development. Principals of schools were expected to develop structures and adopt management and leadership styles which were participative, inclusive and developmental. Many principals would not have been prepared for this shift in mindset, and notions of full participation in governance by parents, and representation of learners through constituted bodies would have been new to them. In this case study of one semi-urban secondary school in the Eastern Cape the researcher sought to establish whether and to what extent the school had moved towards the new management and leadership approaches. The study is interpretive in orientation, and made use of interviews and document analysis. This research has found that the school had democratised its management and leadership to a considerable degree, but that this was not necessarily due to profound changes on the part of the principal 's leadership. The principal emerged as a democratic leader by nature. More significant seem to be the structures which the school had put in place, both officially and internally, to promote widespread participation and the distribution of leadership. This decentralised system of management has contributed to a distinct organisation culture in the school characterised by warmth, openness and ubuntu.
- Full Text:
- Date Issued: 2008
- Authors: Lombo, Mzimkhulu Solomon
- Date: 2008
- Subjects: Education -- South Africa -- Eastern Cape , Education and state -- South Africa -- Eastern Cape , Education -- Political aspects -- South Africa -- Eastern Cape , Education, Secondary -- South Africa -- Eastern Cape -- Case studies , Educational change -- South Africa -- Eastern Cape , Educational leadership -- South Africa -- Eastern Cape , School management and organization -- South Africa -- Eastern Cape , South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2001 , http://hdl.handle.net/10962/d1015541
- Description: The advent of political democracy in South Africa in 1994 gave rise to new policy in education promoting democratic and participative ways of managing and leading schools. The intention was both to break from the apartheid past which was characterised by an authoritarian, nonparticipative mindset, as well as to point the way for future education development. Principals of schools were expected to develop structures and adopt management and leadership styles which were participative, inclusive and developmental. Many principals would not have been prepared for this shift in mindset, and notions of full participation in governance by parents, and representation of learners through constituted bodies would have been new to them. In this case study of one semi-urban secondary school in the Eastern Cape the researcher sought to establish whether and to what extent the school had moved towards the new management and leadership approaches. The study is interpretive in orientation, and made use of interviews and document analysis. This research has found that the school had democratised its management and leadership to a considerable degree, but that this was not necessarily due to profound changes on the part of the principal 's leadership. The principal emerged as a democratic leader by nature. More significant seem to be the structures which the school had put in place, both officially and internally, to promote widespread participation and the distribution of leadership. This decentralised system of management has contributed to a distinct organisation culture in the school characterised by warmth, openness and ubuntu.
- Full Text:
- Date Issued: 2008
Studies towards the synthesis of novel, coumarin-based HIV-1 protease inhibitors
- Authors: Rashamuse, Thompho Jason
- Date: 2008
- Subjects: Coumarins , Protease Inhibitors , HIV infections -- Treatment , HIV (Viruses) , AIDS (Disease) -- Treatment , Heterocyclic compounds -- Derivatives
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4359 , http://hdl.handle.net/10962/d1005024 , Coumarins , Protease Inhibitors , HIV infections -- Treatment , HIV (Viruses) , AIDS (Disease) -- Treatment , Heterocyclic compounds -- Derivatives
- Description: A series of the Baylis-Hillman adducts have been obtained by reacting protected O-benzylated and unprotected substituted salicylaldehydes with methyl acrylate or tertbutyl acrylate, respectively, using DABCO as catalyst. Treatment of the Baylis-Hillman adducts with HCl in a mixture of acetic acid and acetic anhydride afforded the corresponding 3-(chloromethyl)coumarin derivatives with yields of up to 94%. Similar use of HI afforded the corresponding 3-(iodomethyl)coumarins but, depending on the reaction time, the reduced 3-methyl analogues could also be obtained. Arbuzov reactions of the 3-(halomethyl)coumarin derivatives have been undertaken to afford 4-phosphorylated and 1’-phosphorylated derivatives, regioselectivity being dependent on the halide-leaving group. The 3-(chloromethyl)coumarin derivatives have been subjected to nucleophilic (SN) attack by benzylamine to give the corresponding 3- [(benzylamino)methyl]coumarin derivatives in yields of up to 74%. Further treatment of the 3-[(benzylamino)methyl]coumarin derivatives with chloroacetyl chloride afforded the chloroacetamide derivatives, which exhibit hindered rotation about the amine C(O)-N bond. The acetamide derivatives have also been subjected to Arbuzov reaction conditions to afford the phosphorylated derivatives in yields of up to 86%. In a preliminary modelling study, hydrolysed analogues of the synthesized phosphorylated derivatives have been docked into the active site of the HIV-1 protease enzyme using the Cerius-2 Ligandfit software module to provide an insight into potential receptor-ligand hydrogen bonding interactions.
- Full Text:
- Date Issued: 2008
- Authors: Rashamuse, Thompho Jason
- Date: 2008
- Subjects: Coumarins , Protease Inhibitors , HIV infections -- Treatment , HIV (Viruses) , AIDS (Disease) -- Treatment , Heterocyclic compounds -- Derivatives
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4359 , http://hdl.handle.net/10962/d1005024 , Coumarins , Protease Inhibitors , HIV infections -- Treatment , HIV (Viruses) , AIDS (Disease) -- Treatment , Heterocyclic compounds -- Derivatives
- Description: A series of the Baylis-Hillman adducts have been obtained by reacting protected O-benzylated and unprotected substituted salicylaldehydes with methyl acrylate or tertbutyl acrylate, respectively, using DABCO as catalyst. Treatment of the Baylis-Hillman adducts with HCl in a mixture of acetic acid and acetic anhydride afforded the corresponding 3-(chloromethyl)coumarin derivatives with yields of up to 94%. Similar use of HI afforded the corresponding 3-(iodomethyl)coumarins but, depending on the reaction time, the reduced 3-methyl analogues could also be obtained. Arbuzov reactions of the 3-(halomethyl)coumarin derivatives have been undertaken to afford 4-phosphorylated and 1’-phosphorylated derivatives, regioselectivity being dependent on the halide-leaving group. The 3-(chloromethyl)coumarin derivatives have been subjected to nucleophilic (SN) attack by benzylamine to give the corresponding 3- [(benzylamino)methyl]coumarin derivatives in yields of up to 74%. Further treatment of the 3-[(benzylamino)methyl]coumarin derivatives with chloroacetyl chloride afforded the chloroacetamide derivatives, which exhibit hindered rotation about the amine C(O)-N bond. The acetamide derivatives have also been subjected to Arbuzov reaction conditions to afford the phosphorylated derivatives in yields of up to 86%. In a preliminary modelling study, hydrolysed analogues of the synthesized phosphorylated derivatives have been docked into the active site of the HIV-1 protease enzyme using the Cerius-2 Ligandfit software module to provide an insight into potential receptor-ligand hydrogen bonding interactions.
- Full Text:
- Date Issued: 2008
An analysis of local level development in South Africa: a case study of Uitenhage
- Authors: Meyer, Sarah
- Date: 2008
- Subjects: Local government -- South Africa -- Uitenhage -- Case studies Economic development -- South Africa -- Case studies Municipal corporations -- South Africa -- Case studies Community development -- South Africa -- Case studies Cities and towns -- South Africa -- Case studies Social responsibility of business -- South Africa Small business -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4813 , http://hdl.handle.net/10962/d1005487
- Description: Development backlogs, in terms of unemployment and poverty, plague many developing countries. Countries have established and implemented various policies and plans to address these challenges. In response to these development backlogs, South Africa has instituted the notion of decentralisation and developmental local government, whereby local governments are largely responsible for initiating and facilitating development in the area under their jurisdiction. Furthermore, the potential role the private sector can play in development is being increasingly recognised by government, politicians, academics and developers alike. Uitenhage has a strong corporate presence and therefore this sector has the potential to contribute towards development in the town. However the concept of using corporate social responsibility (CSR) to promote development in South Africa is relatively new and, as will be revealed in the case study, definitions and underlying motivation for undertaking CSR vary. Local Economic Development (LED) and, more recently, CSR, have been recognised as major drivers of development and are being implemented throughout the country. As this thesis illustrates, they often merge and can work hand-in-hand to promote local development. Although the private sector, through CSR has the potential to contribute to development, they often do not have the available human resources to implement development initiatives. As is evident in the case study, partnerships between the private and public sectors often emerge as a result. Development institutions play a key role in development and often assist in bridging the gap between citizens, the state and the market. The development institutions in Uitenhage often act as instigators and facilitators on behalf of the larger corporations. The case study in Uitenhage, is a locality where there is a strong automotive industrial cluster and several major firms which are active in the development process. Furthermore, development institutions are committed to the socio-economic development of the town and the promotion of small micro medium enterprises (SMMEs), through various support services. The development institutions, often in partnership with the local government and the public sector, have initiated various local developmental projects in the town, of which three will be discussed in the case study. In this thesis, case study research reveals that corporations often do not meet their potential developmental role and their CSR actions are often considered as ‘window-dressing’ aimed at boosting their corporate image. Similarly, with regard to the development institutions, their development and job creation results look impressive at first glance, but further investigation reveals a collapse of a large number of projects. Despite the potential of LED and CSR to be major drivers of local development, there are still a number of hindering factors, which will be revealed in this thesis and lessons to be learnt which can help to inform future local development projects
- Full Text:
- Date Issued: 2008
- Authors: Meyer, Sarah
- Date: 2008
- Subjects: Local government -- South Africa -- Uitenhage -- Case studies Economic development -- South Africa -- Case studies Municipal corporations -- South Africa -- Case studies Community development -- South Africa -- Case studies Cities and towns -- South Africa -- Case studies Social responsibility of business -- South Africa Small business -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4813 , http://hdl.handle.net/10962/d1005487
- Description: Development backlogs, in terms of unemployment and poverty, plague many developing countries. Countries have established and implemented various policies and plans to address these challenges. In response to these development backlogs, South Africa has instituted the notion of decentralisation and developmental local government, whereby local governments are largely responsible for initiating and facilitating development in the area under their jurisdiction. Furthermore, the potential role the private sector can play in development is being increasingly recognised by government, politicians, academics and developers alike. Uitenhage has a strong corporate presence and therefore this sector has the potential to contribute towards development in the town. However the concept of using corporate social responsibility (CSR) to promote development in South Africa is relatively new and, as will be revealed in the case study, definitions and underlying motivation for undertaking CSR vary. Local Economic Development (LED) and, more recently, CSR, have been recognised as major drivers of development and are being implemented throughout the country. As this thesis illustrates, they often merge and can work hand-in-hand to promote local development. Although the private sector, through CSR has the potential to contribute to development, they often do not have the available human resources to implement development initiatives. As is evident in the case study, partnerships between the private and public sectors often emerge as a result. Development institutions play a key role in development and often assist in bridging the gap between citizens, the state and the market. The development institutions in Uitenhage often act as instigators and facilitators on behalf of the larger corporations. The case study in Uitenhage, is a locality where there is a strong automotive industrial cluster and several major firms which are active in the development process. Furthermore, development institutions are committed to the socio-economic development of the town and the promotion of small micro medium enterprises (SMMEs), through various support services. The development institutions, often in partnership with the local government and the public sector, have initiated various local developmental projects in the town, of which three will be discussed in the case study. In this thesis, case study research reveals that corporations often do not meet their potential developmental role and their CSR actions are often considered as ‘window-dressing’ aimed at boosting their corporate image. Similarly, with regard to the development institutions, their development and job creation results look impressive at first glance, but further investigation reveals a collapse of a large number of projects. Despite the potential of LED and CSR to be major drivers of local development, there are still a number of hindering factors, which will be revealed in this thesis and lessons to be learnt which can help to inform future local development projects
- Full Text:
- Date Issued: 2008
Connection management applications for high-speed audio networking
- Authors: Sibanda, Phathisile
- Date: 2008 , 2008-03-12
- Subjects: Flash (Computer file) , Computer networks , Computer networks -- Management , Digital communications , Computer sound processing , Sound -- Recording and reproducing -- Digital techniques , Broadcast data systems , C# (Computer program language) , C++ (Computer program language) , ActionScript (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4634 , http://hdl.handle.net/10962/d1006532 , Flash (Computer file) , Computer networks , Computer networks -- Management , Digital communications , Computer sound processing , Sound -- Recording and reproducing -- Digital techniques , Broadcast data systems , C# (Computer program language) , C++ (Computer program language) , ActionScript (Computer program language)
- Description: Traditionally, connection management applications (referred to as patchbays) for high-speed audio networking, are predominantly developed using third-generation languages such as C, C# and C++. Due to the rapid increase in distributed audio/video network usage in the world today, connection management applications that control signal routing over these networks have also evolved in complexity to accommodate more functionality. As the result, high-speed audio networking application developers require a tool that will enable them to develop complex connection management applications easily and within the shortest possible time. In addition, this tool should provide them with the reliability and flexibility required to develop applications controlling signal routing in networks carrying real-time data. High-speed audio networks are used for various purposes that include audio/video production and broadcasting. This investigation evaluates the possibility of using Adobe Flash Professional 8, using ActionScript 2.0, for developing connection management applications. Three patchbays, namely the Broadcast patchbay, the Project studio patchbay, and the Hospitality/Convention Centre patchbay were developed and tested for connection management in three sound installation networks, namely the Broadcast network, the Project studio network, and the Hospitality/Convention Centre network. Findings indicate that complex connection management applications can effectively be implemented using the Adobe Flash IDE and ActionScript 2.0.
- Full Text:
- Date Issued: 2008
- Authors: Sibanda, Phathisile
- Date: 2008 , 2008-03-12
- Subjects: Flash (Computer file) , Computer networks , Computer networks -- Management , Digital communications , Computer sound processing , Sound -- Recording and reproducing -- Digital techniques , Broadcast data systems , C# (Computer program language) , C++ (Computer program language) , ActionScript (Computer program language)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4634 , http://hdl.handle.net/10962/d1006532 , Flash (Computer file) , Computer networks , Computer networks -- Management , Digital communications , Computer sound processing , Sound -- Recording and reproducing -- Digital techniques , Broadcast data systems , C# (Computer program language) , C++ (Computer program language) , ActionScript (Computer program language)
- Description: Traditionally, connection management applications (referred to as patchbays) for high-speed audio networking, are predominantly developed using third-generation languages such as C, C# and C++. Due to the rapid increase in distributed audio/video network usage in the world today, connection management applications that control signal routing over these networks have also evolved in complexity to accommodate more functionality. As the result, high-speed audio networking application developers require a tool that will enable them to develop complex connection management applications easily and within the shortest possible time. In addition, this tool should provide them with the reliability and flexibility required to develop applications controlling signal routing in networks carrying real-time data. High-speed audio networks are used for various purposes that include audio/video production and broadcasting. This investigation evaluates the possibility of using Adobe Flash Professional 8, using ActionScript 2.0, for developing connection management applications. Three patchbays, namely the Broadcast patchbay, the Project studio patchbay, and the Hospitality/Convention Centre patchbay were developed and tested for connection management in three sound installation networks, namely the Broadcast network, the Project studio network, and the Hospitality/Convention Centre network. Findings indicate that complex connection management applications can effectively be implemented using the Adobe Flash IDE and ActionScript 2.0.
- Full Text:
- Date Issued: 2008
An evaluation of the process and impact of outsourcing information technology (IT) services by Eastern Cape Treasury Department (ECTD) to the State Information Technology Agency (SITA)
- Authors: Mdlokovi, Lulama Reuben
- Date: 2008
- Subjects: State Information Technology Agency (South Africa) Administrative agencies -- South Africa Information technology -- Management Technology -- Information services Information services industry Telecommunication Value-added networks (Computer networks)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:743 , http://hdl.handle.net/10962/d1003864
- Description: The aim of this research is to evaluate the process and impact of outsourcing information technology (IT) services of Eastern Cape Treasury Department (ECTD) to State Information Technology Agency (SITA). This research study has been prompted by the fact that the South African Government through the National Department of Public Service and Administration has established SITA with a sole purpose of improving service delivery by all national, provincial and local government departments. The researcher’s concern is whether the relationship between SITA and these departments is working or not. The research paradigm adopted is a constructivist approach and the ontological position adopted assumed multiple realities. The research method used in this study is the evaluation research method. Key to the research procedure was the fact that four senior officials were interviewed using audio recording, where in two were each chosen from SITA and ECTD. The researcher used document analysis and interviews as a means of collecting data. Separate open-ended questions for SITA and ECTD were structured in such a way that it would be easy to extract themes describing the details of a particular question. The researcher made use of thematic analysis. The theory drive-code development process was key in the research analysis. ECTD outsourced to SITA the following IT services, namely, provision or maintenance of a private telecommunication network (PTN) or a value-added network (VAN); transversal information systems and its data-processing or associated services; training in IT/IS; application software development; maintenance services for IT software or infrastructure; data-processing or associated services for specific IT applications or systems such as website development; and IT support. The interviewed officials from ECTD contend that they used the SCM Guide and SITA ACT when pursuing IT outsourcing for projects such as those listed above. One of the key projects outsourced to SITA is the IFMS, which is a project programme of the National Treasury Department working closely with provinces (e.g. ECTD), National Department of Public Service and Administration (NDPSA) and SITA. The IFMS project has been implemented following the SCM guidelines. The key SCM Guide components are demand, acquisition, logistics, and disposal management. The engagement model used by SITA to guide them on the process of engaging in an IT outsourcing relationship has, according to the officials interviewed, been a success. SITA uses a standard contract wherein other specific contracts receive minor adjustments. The impact of IT outsourcing has shown increases in customer satisfaction improvement, transformation of government procurement and provisioning practices, appointment of Consultants, interpretation of the Preferential Procurement Policy, promotion of the consistent application of Best Practices, information systems security environment, and improving service delivery.
- Full Text:
- Date Issued: 2008
- Authors: Mdlokovi, Lulama Reuben
- Date: 2008
- Subjects: State Information Technology Agency (South Africa) Administrative agencies -- South Africa Information technology -- Management Technology -- Information services Information services industry Telecommunication Value-added networks (Computer networks)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:743 , http://hdl.handle.net/10962/d1003864
- Description: The aim of this research is to evaluate the process and impact of outsourcing information technology (IT) services of Eastern Cape Treasury Department (ECTD) to State Information Technology Agency (SITA). This research study has been prompted by the fact that the South African Government through the National Department of Public Service and Administration has established SITA with a sole purpose of improving service delivery by all national, provincial and local government departments. The researcher’s concern is whether the relationship between SITA and these departments is working or not. The research paradigm adopted is a constructivist approach and the ontological position adopted assumed multiple realities. The research method used in this study is the evaluation research method. Key to the research procedure was the fact that four senior officials were interviewed using audio recording, where in two were each chosen from SITA and ECTD. The researcher used document analysis and interviews as a means of collecting data. Separate open-ended questions for SITA and ECTD were structured in such a way that it would be easy to extract themes describing the details of a particular question. The researcher made use of thematic analysis. The theory drive-code development process was key in the research analysis. ECTD outsourced to SITA the following IT services, namely, provision or maintenance of a private telecommunication network (PTN) or a value-added network (VAN); transversal information systems and its data-processing or associated services; training in IT/IS; application software development; maintenance services for IT software or infrastructure; data-processing or associated services for specific IT applications or systems such as website development; and IT support. The interviewed officials from ECTD contend that they used the SCM Guide and SITA ACT when pursuing IT outsourcing for projects such as those listed above. One of the key projects outsourced to SITA is the IFMS, which is a project programme of the National Treasury Department working closely with provinces (e.g. ECTD), National Department of Public Service and Administration (NDPSA) and SITA. The IFMS project has been implemented following the SCM guidelines. The key SCM Guide components are demand, acquisition, logistics, and disposal management. The engagement model used by SITA to guide them on the process of engaging in an IT outsourcing relationship has, according to the officials interviewed, been a success. SITA uses a standard contract wherein other specific contracts receive minor adjustments. The impact of IT outsourcing has shown increases in customer satisfaction improvement, transformation of government procurement and provisioning practices, appointment of Consultants, interpretation of the Preferential Procurement Policy, promotion of the consistent application of Best Practices, information systems security environment, and improving service delivery.
- Full Text:
- Date Issued: 2008
Understanding and improving the residual efficacy of the cryptophlebia leucotreta granulovirus (Cryptogran)
- Authors: Kirkman, Wayne
- Date: 2008
- Subjects: Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Citrus -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5794 , http://hdl.handle.net/10962/d1005482 , Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Citrus -- Diseases and pests
- Description: False codling moth (FCM), Thaumatotibia (=Cryptophlebia) leucotreta (Meyr) (Lepidoptera: Tortricidae), is one of the most important pests on citrus. The Cryptophlebia leucotreta granulovirus (CrleGV) has been developed into a successful biological control agent, registered under the name Cryptogran, and is currently the preferred product for the control of FCM on citrus in South Africa. A prerequisite to the continued success of Cryptogran as a means of controlling false codling moth is to understand the factors affecting field persistence of the virus, and to find ways to improve it. The aim of this study was to gain a clearer understanding of the product and the abiotic and biotic factors affecting its persistence in the field, and to investigate methods to improve this persistence. The effect of UV-irradiation on the virus was determined, and various products were tested as UV protectants in laboratory bioassays. Lignin was the most effective additive, and was tested in several field trials, where it also enhanced the efficacy of Cryptogran. Laboratory trials indicated that Cryptogran is rainfast. Cryptogran applications early in the season had a longer period of residual activity than sprays applied closer to harvest. Daytime applications were less effective that evening sprays. Sprays applied coinciding with peaks in pheromone moth trap catches were more effective than those applied between peaks. Biotic factors influencing persistence were investigated. Residual efficacy was longer when treatments were applied to blocks than as single tree treatments. Attempts were made to quantify the effect of the navel end of a navel orange on the field persistence of Cryptogran. Cryptogran was shown to be compatible with many agricultural chemicals used on citrus. Economic thresholds and various cost-benefit analyses are discussed. A list of practical recommendations to growers was drawn up, and possibilities for future research are presented.
- Full Text:
- Date Issued: 2008
- Authors: Kirkman, Wayne
- Date: 2008
- Subjects: Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Citrus -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5794 , http://hdl.handle.net/10962/d1005482 , Cryptophlebia leucotreta , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Citrus -- Diseases and pests
- Description: False codling moth (FCM), Thaumatotibia (=Cryptophlebia) leucotreta (Meyr) (Lepidoptera: Tortricidae), is one of the most important pests on citrus. The Cryptophlebia leucotreta granulovirus (CrleGV) has been developed into a successful biological control agent, registered under the name Cryptogran, and is currently the preferred product for the control of FCM on citrus in South Africa. A prerequisite to the continued success of Cryptogran as a means of controlling false codling moth is to understand the factors affecting field persistence of the virus, and to find ways to improve it. The aim of this study was to gain a clearer understanding of the product and the abiotic and biotic factors affecting its persistence in the field, and to investigate methods to improve this persistence. The effect of UV-irradiation on the virus was determined, and various products were tested as UV protectants in laboratory bioassays. Lignin was the most effective additive, and was tested in several field trials, where it also enhanced the efficacy of Cryptogran. Laboratory trials indicated that Cryptogran is rainfast. Cryptogran applications early in the season had a longer period of residual activity than sprays applied closer to harvest. Daytime applications were less effective that evening sprays. Sprays applied coinciding with peaks in pheromone moth trap catches were more effective than those applied between peaks. Biotic factors influencing persistence were investigated. Residual efficacy was longer when treatments were applied to blocks than as single tree treatments. Attempts were made to quantify the effect of the navel end of a navel orange on the field persistence of Cryptogran. Cryptogran was shown to be compatible with many agricultural chemicals used on citrus. Economic thresholds and various cost-benefit analyses are discussed. A list of practical recommendations to growers was drawn up, and possibilities for future research are presented.
- Full Text:
- Date Issued: 2008
Synthetic, spectrometric and computer modelling studies of novel ATP analogues
- Gxoyiya, Babalwa Siliziwe Blossom
- Authors: Gxoyiya, Babalwa Siliziwe Blossom
- Date: 2008
- Subjects: Spectrum analysis Tuberculosis -- Treatment Chemotherapy Adenosine triphosphate Adenosine triphosphate -- Synthesis Adenosine triphosphate -- Computer simulation Adenosine triphosphate -- Spectrometric imaging Glutamine synthetase Tuberculosis -- Chemotherapy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4386 , http://hdl.handle.net/10962/d1005051
- Description: This study has been concerned with the design and synthesis of A TP analogues with the potential to act as inhibitors of glutamine synthetase - a novel target for therapeutic intervention in the treatment of tuberculosis. Using a structural -analogy approach, various 3-indolylalkanoic acid, benzimidazole and pyrazolo[3,4-dJpyrimidine derivatives have been prepared and characterized. Alkylation of the heterocyclic bases using 4-(bromomethyl)-2,2-dimethyl-1 ,3-d ioxolane, 2-(bromomethoxy)ethyl acetate and 2-(chloroethoxy)ethanol in the presence of either NaH or BulOK afforded the corresponding N-alkylated derivatives of benzimidazole and 4-aminopyrazolo[3,4-dJpyrimidine (4-APP). Similar reactions with 3-indo lylalkanoic esters resulted in O-alkyl cleavage with the formation of new esters. Alkylation of benzimidazole with allyl bromide, 4-bromobutene and 2-methylbut-2-ene has also been shown to afford the corresponding l-alkenylbenzimidazoles in moderate to excellent yield (43-96%). Subsequent oxidation of these products using CTAP, gave the dihydroxy derivatives in poor to good yields (26-77%). Phosphorylation of various hydroxy derivatives of benzimidazole and 4-APP has been achieved using diethyl chlorophosphate to afford the corresponding monophosphate and 1,2-diphosphate esters. Glycosylation of each of the heterocyclic bases has been successfully achieved using 1,2,3,4,6-penta-O-acetyl-D-glucopyranose and SnCl4 in acetonitri le, while methanolysis of the resulting tetraacetates, using methanolic NaOMe, afforded the hydroxy derivatives in good yield (50-70%). Various 1- and 2-dimensional NMR spectroscopic methods (e.g., IH, 13C, lip, COSY, HSQC and HMBC) have been used to confirm the structures of the synthesized A IP analogues. The application of NMR prediction programmes has been explored, permitting assessment of their agreement with the experimental data and confirmation of assigned structures. High-resolution electron impact (EI) mass spectrometric data have been used to explore the mass fragmentation pathways exhibited by selected derivatives, and certain common fragmentations have been identified. Molecular modelling of selected products as potential glutamine synthetase ligands has been performed on the Accelrys Cerius2 platform, and interactive receptor-ligand docking studies have been conducted using the Ligand-Fit module. These studies have revealed possible hydrogen-boding interactions between the selected analogues and various amino acid residues in the glutamine synthetase active site.
- Full Text:
- Date Issued: 2008
- Authors: Gxoyiya, Babalwa Siliziwe Blossom
- Date: 2008
- Subjects: Spectrum analysis Tuberculosis -- Treatment Chemotherapy Adenosine triphosphate Adenosine triphosphate -- Synthesis Adenosine triphosphate -- Computer simulation Adenosine triphosphate -- Spectrometric imaging Glutamine synthetase Tuberculosis -- Chemotherapy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4386 , http://hdl.handle.net/10962/d1005051
- Description: This study has been concerned with the design and synthesis of A TP analogues with the potential to act as inhibitors of glutamine synthetase - a novel target for therapeutic intervention in the treatment of tuberculosis. Using a structural -analogy approach, various 3-indolylalkanoic acid, benzimidazole and pyrazolo[3,4-dJpyrimidine derivatives have been prepared and characterized. Alkylation of the heterocyclic bases using 4-(bromomethyl)-2,2-dimethyl-1 ,3-d ioxolane, 2-(bromomethoxy)ethyl acetate and 2-(chloroethoxy)ethanol in the presence of either NaH or BulOK afforded the corresponding N-alkylated derivatives of benzimidazole and 4-aminopyrazolo[3,4-dJpyrimidine (4-APP). Similar reactions with 3-indo lylalkanoic esters resulted in O-alkyl cleavage with the formation of new esters. Alkylation of benzimidazole with allyl bromide, 4-bromobutene and 2-methylbut-2-ene has also been shown to afford the corresponding l-alkenylbenzimidazoles in moderate to excellent yield (43-96%). Subsequent oxidation of these products using CTAP, gave the dihydroxy derivatives in poor to good yields (26-77%). Phosphorylation of various hydroxy derivatives of benzimidazole and 4-APP has been achieved using diethyl chlorophosphate to afford the corresponding monophosphate and 1,2-diphosphate esters. Glycosylation of each of the heterocyclic bases has been successfully achieved using 1,2,3,4,6-penta-O-acetyl-D-glucopyranose and SnCl4 in acetonitri le, while methanolysis of the resulting tetraacetates, using methanolic NaOMe, afforded the hydroxy derivatives in good yield (50-70%). Various 1- and 2-dimensional NMR spectroscopic methods (e.g., IH, 13C, lip, COSY, HSQC and HMBC) have been used to confirm the structures of the synthesized A IP analogues. The application of NMR prediction programmes has been explored, permitting assessment of their agreement with the experimental data and confirmation of assigned structures. High-resolution electron impact (EI) mass spectrometric data have been used to explore the mass fragmentation pathways exhibited by selected derivatives, and certain common fragmentations have been identified. Molecular modelling of selected products as potential glutamine synthetase ligands has been performed on the Accelrys Cerius2 platform, and interactive receptor-ligand docking studies have been conducted using the Ligand-Fit module. These studies have revealed possible hydrogen-boding interactions between the selected analogues and various amino acid residues in the glutamine synthetase active site.
- Full Text:
- Date Issued: 2008
Synthesis, photophysics and electrochemical study of tin macrocycles
- Authors: Khene, Mielie Samson
- Date: 2008
- Subjects: Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4376 , http://hdl.handle.net/10962/d1005041 , Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
- Description: Three non-peripherally substituted tin(IV) macrocylic compounds, octahexylphthalocyaninato dichlorotin(IV) (35a), octahexyltetrabenzo-5,10,15-triazaporphyrinato dichlorotin(IV) (35b) and octadecylphthalocyaninato dichlorotin(IV) (35c) were synthesized and their photophysical and electrochemical behaviour studied. Complex (35b), containing a CH group in place of one of the aza nitrogen atom of the phthalocyanine core, shows a split Q band due to its lower symmetry. The triplet state quantum yields were found to be lower than would be expected on the basis of the heavy atom effect of tin as the central metal for phthalocyanine derivatives (35a and 35c). In contrast, (35b) shows a triplet quantum yield ΦT = 0.78. The triplet state lifetimes were solvent dependent, and were higher in THF than in toluene. Cyclic voltammetry and spectroelectrochemistry of the complexes revealed only ring based redox processes. This thesis also reports on the microwave syntheses of tetrasulphonated tin phthalocyanine and tetrasulphonated tin α,β,γ-tetrabenzcorrole. The latter was only formed at low ratios (< 1:8) of 4-sulfophthalic acid to urea. Both complexes are aggregated in aqueous media, but can be partly or fully disaggregated by the addition of Triton X-100. The SnTSTBC complex has lower triplet life times and yields, while binding constant and quenching (of bovine serum albumin) constant are lower for SnTSTBC, compared to SnTSPc. Finally Non-peripherally (α) tetra- (40) and octa-(38a) substituted dodecyl-mercapto tin(IV) phthalocyanines where synthesized and the electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for (38a) and (40); the former shows two ring oxidations, while the latter shows only one ring based oxidation. The adsorption kinetics of (38a) and (40) on a gold electrode have been investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy ΔG(ads) of the self-assembled monolayer (SAMs) were evaluated based on the Frumkin isotherm. The interaction factor between adsorbate –adsorbate molecules is also discussed.
- Full Text:
- Date Issued: 2008
- Authors: Khene, Mielie Samson
- Date: 2008
- Subjects: Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4376 , http://hdl.handle.net/10962/d1005041 , Electrochemistry , Photochemistry , Phthalocyanines , Macrocyclic compounds , Spectrum analysis
- Description: Three non-peripherally substituted tin(IV) macrocylic compounds, octahexylphthalocyaninato dichlorotin(IV) (35a), octahexyltetrabenzo-5,10,15-triazaporphyrinato dichlorotin(IV) (35b) and octadecylphthalocyaninato dichlorotin(IV) (35c) were synthesized and their photophysical and electrochemical behaviour studied. Complex (35b), containing a CH group in place of one of the aza nitrogen atom of the phthalocyanine core, shows a split Q band due to its lower symmetry. The triplet state quantum yields were found to be lower than would be expected on the basis of the heavy atom effect of tin as the central metal for phthalocyanine derivatives (35a and 35c). In contrast, (35b) shows a triplet quantum yield ΦT = 0.78. The triplet state lifetimes were solvent dependent, and were higher in THF than in toluene. Cyclic voltammetry and spectroelectrochemistry of the complexes revealed only ring based redox processes. This thesis also reports on the microwave syntheses of tetrasulphonated tin phthalocyanine and tetrasulphonated tin α,β,γ-tetrabenzcorrole. The latter was only formed at low ratios (< 1:8) of 4-sulfophthalic acid to urea. Both complexes are aggregated in aqueous media, but can be partly or fully disaggregated by the addition of Triton X-100. The SnTSTBC complex has lower triplet life times and yields, while binding constant and quenching (of bovine serum albumin) constant are lower for SnTSTBC, compared to SnTSPc. Finally Non-peripherally (α) tetra- (40) and octa-(38a) substituted dodecyl-mercapto tin(IV) phthalocyanines where synthesized and the electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for (38a) and (40); the former shows two ring oxidations, while the latter shows only one ring based oxidation. The adsorption kinetics of (38a) and (40) on a gold electrode have been investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy ΔG(ads) of the self-assembled monolayer (SAMs) were evaluated based on the Frumkin isotherm. The interaction factor between adsorbate –adsorbate molecules is also discussed.
- Full Text:
- Date Issued: 2008
Tripping over our own feet : a critical discussion of Trade Related Intellectual Property Rights (TRIPS) with specific reference to their impact on South Africa's ability to combat HIV and AIDS
- Authors: Brennan, Jade
- Date: 2008
- Subjects: Agreement on Trade-Related Aspects of Intellectual Property Rights, (1994) Trade regulation -- South Africa Intellectual property -- South Africa HIV (Viruses) -- South Africa AIDS (Disease) -- South Africa Patients -- Civil rights -- South Africa Human rights -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2850 , http://hdl.handle.net/10962/d1006316
- Description: This thesis aims to look at the agreement on Trade Related Intellectual Property Rights (TRIPS) with specific reference to their impact on South Africa's ability to combat HIV and AIDS. It begins by looking at the history of patents and intellectual property rights and illustrates why and how the TRIPS Agreement came into existence. The TRIPS Agreement exemplifies the disparities between developed and developing countries and this can clearly be seen with regard to the provision of anti-HIV and AIDS drugs. The developing world deals with the bulk of the HIV and AIDS epidemic whilst the developed world holds most of the patents on the medication needed to treat those living with HIV and AIDS. This situation lends itself to a rift between patient rights on the one hand, and patent rights on the other. Traditionally the state has been the provider of rights such as health, but TRIPS alters this to include strong patent protection that is in line with neo liberal doctrine. The thesis examines these tensions with specific reference to South Africa's ability successfully to implement programmes to combat HIV and AIDS.
- Full Text:
- Date Issued: 2008
- Authors: Brennan, Jade
- Date: 2008
- Subjects: Agreement on Trade-Related Aspects of Intellectual Property Rights, (1994) Trade regulation -- South Africa Intellectual property -- South Africa HIV (Viruses) -- South Africa AIDS (Disease) -- South Africa Patients -- Civil rights -- South Africa Human rights -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2850 , http://hdl.handle.net/10962/d1006316
- Description: This thesis aims to look at the agreement on Trade Related Intellectual Property Rights (TRIPS) with specific reference to their impact on South Africa's ability to combat HIV and AIDS. It begins by looking at the history of patents and intellectual property rights and illustrates why and how the TRIPS Agreement came into existence. The TRIPS Agreement exemplifies the disparities between developed and developing countries and this can clearly be seen with regard to the provision of anti-HIV and AIDS drugs. The developing world deals with the bulk of the HIV and AIDS epidemic whilst the developed world holds most of the patents on the medication needed to treat those living with HIV and AIDS. This situation lends itself to a rift between patient rights on the one hand, and patent rights on the other. Traditionally the state has been the provider of rights such as health, but TRIPS alters this to include strong patent protection that is in line with neo liberal doctrine. The thesis examines these tensions with specific reference to South Africa's ability successfully to implement programmes to combat HIV and AIDS.
- Full Text:
- Date Issued: 2008
Investigating aspects of corporate citizenship on private game farms: the case of Mtshelezi Game Reserve in Makana Municipality, Eastern Cape Province
- Authors: Nyama, Cynthia
- Date: 2008
- Subjects: Tourism -- South Africa -- Eastern Cape , Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions , Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions , Social responsibility of business -- South Africa -- Eastern Cape , Ecotourism -- South Africa -- Eastern Cape -- Citizen participation , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:751 , http://hdl.handle.net/10962/d1003872 , Tourism -- South Africa -- Eastern Cape , Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions , Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions , Social responsibility of business -- South Africa -- Eastern Cape , Ecotourism -- South Africa -- Eastern Cape -- Citizen participation , Rural development -- South Africa -- Eastern Cape
- Description: Research show that post 1996 period has experienced an unprecedented increase in game based operations. The corporate citizenship or corporate social responsibility of the game reserves is of much interest to this study with a focus on the rights of previous and current occupants of farms, workers’ well-being, job creation, quality of life and poverty alleviation within the game/tourism industry. The research was conducted as a qualitative case study and the tools employed for data gathering include: a review of the relevant literature, interviews (face-to-face), the administering of a questionnaire survey and document analysis from diversity of resources which include the Department of Labour, East Cape Agricultural Research Project, and through use of multiple data sources. The approach taken in this dissertation is to examine to what extent the private game reserves in the Makana Municipality can be labelled as “corporate citizens” and this was done by means of a case study of one private game reserve. The areas that are deemed to be most important in this regard are (i) employment history (ii) educational opportunities (iii) wages (iv) housing (v) land tenure. The study established that younger, better educated people are likely to secure better paying employment on PGR. The nature and conditions of sale of the farm to the PGR can impact on the employment secured by workers in the new dispensation. Workers are tied to these jobs because of the very long hours that prevent them from doing anything else to earn money. Some of the workers had opportunities to learn new skills but the question remains; which people are these and how long will growing differentials in earnings reproduce the poorly educated worker in the next generation. The study also high lightened the need for academics and researchers to come with a common set of corporate citizenship measures such as to measure corporate social impacts.
- Full Text:
- Date Issued: 2008
- Authors: Nyama, Cynthia
- Date: 2008
- Subjects: Tourism -- South Africa -- Eastern Cape , Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions , Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions , Social responsibility of business -- South Africa -- Eastern Cape , Ecotourism -- South Africa -- Eastern Cape -- Citizen participation , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:751 , http://hdl.handle.net/10962/d1003872 , Tourism -- South Africa -- Eastern Cape , Game farms -- South Africa -- Eastern Cape , Agricultural laborers -- South Africa -- Eastern Cape -- Social conditions , Agricultural laborers -- South Africa -- Eastern Cape -- Economic conditions , Social responsibility of business -- South Africa -- Eastern Cape , Ecotourism -- South Africa -- Eastern Cape -- Citizen participation , Rural development -- South Africa -- Eastern Cape
- Description: Research show that post 1996 period has experienced an unprecedented increase in game based operations. The corporate citizenship or corporate social responsibility of the game reserves is of much interest to this study with a focus on the rights of previous and current occupants of farms, workers’ well-being, job creation, quality of life and poverty alleviation within the game/tourism industry. The research was conducted as a qualitative case study and the tools employed for data gathering include: a review of the relevant literature, interviews (face-to-face), the administering of a questionnaire survey and document analysis from diversity of resources which include the Department of Labour, East Cape Agricultural Research Project, and through use of multiple data sources. The approach taken in this dissertation is to examine to what extent the private game reserves in the Makana Municipality can be labelled as “corporate citizens” and this was done by means of a case study of one private game reserve. The areas that are deemed to be most important in this regard are (i) employment history (ii) educational opportunities (iii) wages (iv) housing (v) land tenure. The study established that younger, better educated people are likely to secure better paying employment on PGR. The nature and conditions of sale of the farm to the PGR can impact on the employment secured by workers in the new dispensation. Workers are tied to these jobs because of the very long hours that prevent them from doing anything else to earn money. Some of the workers had opportunities to learn new skills but the question remains; which people are these and how long will growing differentials in earnings reproduce the poorly educated worker in the next generation. The study also high lightened the need for academics and researchers to come with a common set of corporate citizenship measures such as to measure corporate social impacts.
- Full Text:
- Date Issued: 2008
ATP mimics as glutamine synthetase inhibitors : an exploratory synthetic study
- Authors: Salisu, Sheriff Tomilola
- Date: 2008
- Subjects: Glutamine synthetase Tuberculosis -- Treatment Tuberculosis -- Chemotherapy Adenosine triphosphate Adenosine triphosphate -- Synthesis Drug development
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4408 , http://hdl.handle.net/10962/d1006715
- Description: Using a mechanism-based approach to drug discovery, efforts have been directed towards developing novel ATP mimics that can act as GS inhibitors. The purine-based systems, adenosine, adenine and allopurinol, were identified as possible scaffolds for potential ATP mimics, while various meta-disubstituted benzenoid compounds, 3-aminobenzonitrile, 3-aminophenol, resorcinol, 3-aminobenzyl alcohol, 3-hydroxybenzoic acid and 3-aminobenzoic acid have been explored as adenine analogues. These compounds were treated with different alkylating and acylating agents. Allylation of all the substrates was achieved using allyl bromide and N-9 alkylation of protected allopurinol was effected using a number of specially prepared Baylis-Hillman adducts. Acylation of the benzenoid precursors with chloroacetyl chloride, acetoxyacetyl chloride, acryloyl chloride and specially prepared 2,3,4,5,6-pentaacetylgluconoyl chloride afforded the corresponding mono- and /or diacylated products in varying yields (4-96%). Elaboration of the alkylated and acylated products has involved the reaction of hydroxy systems with diethyl chloro phosphate and chloro derivatives with triethyl phosphite in Arbuzov-type reactions to afford phosphorylated products. In all cases, products were fully characterized using 1- and 2-D NMR analysis and, where appropriate, high-resolution mass spectrometry. The application of Modgraph and ChemWindow NMR prediction programmes has been explored and the resulting data have been compared with experimental chemical shift assignments to confirm chemical structures and, in some cases, to establish the position of allylation or acylation. Experimental assignments were found to be generally comparable with the Modgraph data, but not always with the ChemWindow values. The docking of selected products in the 'active-site' of GS and their structural homology with ATP, both in their free and bound conformations have been studied using the ACCELERYS Cerius² platform. All the selected ATP mimics exhibit some form of interaction with the 'active-site' residues, and a number of them appear to be promising GS ligands.
- Full Text:
- Date Issued: 2008
- Authors: Salisu, Sheriff Tomilola
- Date: 2008
- Subjects: Glutamine synthetase Tuberculosis -- Treatment Tuberculosis -- Chemotherapy Adenosine triphosphate Adenosine triphosphate -- Synthesis Drug development
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4408 , http://hdl.handle.net/10962/d1006715
- Description: Using a mechanism-based approach to drug discovery, efforts have been directed towards developing novel ATP mimics that can act as GS inhibitors. The purine-based systems, adenosine, adenine and allopurinol, were identified as possible scaffolds for potential ATP mimics, while various meta-disubstituted benzenoid compounds, 3-aminobenzonitrile, 3-aminophenol, resorcinol, 3-aminobenzyl alcohol, 3-hydroxybenzoic acid and 3-aminobenzoic acid have been explored as adenine analogues. These compounds were treated with different alkylating and acylating agents. Allylation of all the substrates was achieved using allyl bromide and N-9 alkylation of protected allopurinol was effected using a number of specially prepared Baylis-Hillman adducts. Acylation of the benzenoid precursors with chloroacetyl chloride, acetoxyacetyl chloride, acryloyl chloride and specially prepared 2,3,4,5,6-pentaacetylgluconoyl chloride afforded the corresponding mono- and /or diacylated products in varying yields (4-96%). Elaboration of the alkylated and acylated products has involved the reaction of hydroxy systems with diethyl chloro phosphate and chloro derivatives with triethyl phosphite in Arbuzov-type reactions to afford phosphorylated products. In all cases, products were fully characterized using 1- and 2-D NMR analysis and, where appropriate, high-resolution mass spectrometry. The application of Modgraph and ChemWindow NMR prediction programmes has been explored and the resulting data have been compared with experimental chemical shift assignments to confirm chemical structures and, in some cases, to establish the position of allylation or acylation. Experimental assignments were found to be generally comparable with the Modgraph data, but not always with the ChemWindow values. The docking of selected products in the 'active-site' of GS and their structural homology with ATP, both in their free and bound conformations have been studied using the ACCELERYS Cerius² platform. All the selected ATP mimics exhibit some form of interaction with the 'active-site' residues, and a number of them appear to be promising GS ligands.
- Full Text:
- Date Issued: 2008
The ecology and conservation of Mackinder's eagle owls (Bubo capensis mackinderi) in central Kenya in relation to agricultural land-use and cultural attitudes
- Authors: Ogada, Darcy L
- Date: 2008
- Subjects: Cape eagle owl -- Kenya Cape eagle owl -- Habitat -- Kenya Cape eagle owl -- Breeding -- Kenya Cape eagle owl -- Nutrition -- Kenya Bubo -- Kenya Wildlife conservation -- Kenya Biodiversity conservation -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5668 , http://hdl.handle.net/10962/d1005353
- Description: The loss of habitat to agriculture is a worldwide problem for biodiversity conservation. One species that has seemingly been able to adapt to the conversion of forests to farmlands is Mackinder’s eagle owl (Bubo capensis mackinderi), which inhabits highland areas, but little is known of its ecology, especially outside of protected areas. This study examined the impact of agricultural practices and farmer’s attitudes on the foraging and population ecology of the Mackinder’s eagle owl in central Kenya. Owl territories were monitored monthly from June 2004- October 2006 for signs of occupancy, breeding activity, mortality and to collect data on food resources. Nest site characteristics were measured for all known nests. Because previous studies showed an affinity for rodents, small mammals were trapped monthly using mark-recapture methodology. In each territory, the type and amount of farm crops were measured each month and farmers were interviewed about their knowledge and beliefs about owls. Mackinder’s eagle owls in central Kenya lived at extremely high density 0.87 owl pairs/km². This density was high compared to other populations of Mackinder’s eagle owl and to Eurasian eagle owl (Bubo bubo) populations in Europe. Breeding success was 48% over three years and this compared well with other species of eagle owl inhabiting human-disturbed areas. All nests and roosts were located in river valleys, and all successful nest sites were located on cliffs or other inaccessible rocky terrain. Nest sites were located adjacent to farms, which provided for both open hunting and an abundance of prey. Breeding activity was concentrated after the rainy seasons and this was likely linked to prey availability after the rains. Agricultural activities generally had a positive effect on rodent populations. Small mammal trapping results revealed that rodents were over 14 times more abundant in farms than in adjacent grassland habitat. This population of Mackinder’s eagle owl had a very catholic diet and consumed mostly mammalian prey species including hares, giant rats, root rats, grooved-tooth rats and small rodents. Small rodents accounted for almost half of the owls’ diet and when their numbers increased, owls responded by consuming more of them, indicating the importance of farming activities to this population of owls. Other populations of eagle owl inhabiting human-disturbed areas had diet widths positively related to levels of habitat disturbance. This result supported optimal foraging theory that more productive environments have predators with more specialized diets, while patchy environments have generalist predators. The ecology of this population of Mackinder’s eagle owls was heavily influenced by human agricultural activities, which generally had a positive effect on their population. Farming activities changed rapidly both within and between seasons as plots were small and neighbouring farmers planted various crops at different times of the year and this was enhanced by irrigation in some areas. Year-round availability of forage within farms had a positive effect on owl prey species, some of which increased relative to the type and amount of crops found in farms. However, 57% of owl injuries and mortalities that occurred were related either directly or indirectly to human activities. Cultural prejudices against owls remain the biggest threat to this population’s long-term persistence. Farmer education was shown to play a significant role in overcoming negative beliefs about owls. Because Mackinder’s eagle owls are highly adaptable to anthropomorphic landscape changes, largely due to their adaptability as food generalists, they are one of the few top predators remaining in this highly disturbed agricultural system. However, populations within agricultural areas remain especially vulnerable to negative human attitudes towards owls due to their close association with human activities.
- Full Text:
- Date Issued: 2008
- Authors: Ogada, Darcy L
- Date: 2008
- Subjects: Cape eagle owl -- Kenya Cape eagle owl -- Habitat -- Kenya Cape eagle owl -- Breeding -- Kenya Cape eagle owl -- Nutrition -- Kenya Bubo -- Kenya Wildlife conservation -- Kenya Biodiversity conservation -- Kenya
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5668 , http://hdl.handle.net/10962/d1005353
- Description: The loss of habitat to agriculture is a worldwide problem for biodiversity conservation. One species that has seemingly been able to adapt to the conversion of forests to farmlands is Mackinder’s eagle owl (Bubo capensis mackinderi), which inhabits highland areas, but little is known of its ecology, especially outside of protected areas. This study examined the impact of agricultural practices and farmer’s attitudes on the foraging and population ecology of the Mackinder’s eagle owl in central Kenya. Owl territories were monitored monthly from June 2004- October 2006 for signs of occupancy, breeding activity, mortality and to collect data on food resources. Nest site characteristics were measured for all known nests. Because previous studies showed an affinity for rodents, small mammals were trapped monthly using mark-recapture methodology. In each territory, the type and amount of farm crops were measured each month and farmers were interviewed about their knowledge and beliefs about owls. Mackinder’s eagle owls in central Kenya lived at extremely high density 0.87 owl pairs/km². This density was high compared to other populations of Mackinder’s eagle owl and to Eurasian eagle owl (Bubo bubo) populations in Europe. Breeding success was 48% over three years and this compared well with other species of eagle owl inhabiting human-disturbed areas. All nests and roosts were located in river valleys, and all successful nest sites were located on cliffs or other inaccessible rocky terrain. Nest sites were located adjacent to farms, which provided for both open hunting and an abundance of prey. Breeding activity was concentrated after the rainy seasons and this was likely linked to prey availability after the rains. Agricultural activities generally had a positive effect on rodent populations. Small mammal trapping results revealed that rodents were over 14 times more abundant in farms than in adjacent grassland habitat. This population of Mackinder’s eagle owl had a very catholic diet and consumed mostly mammalian prey species including hares, giant rats, root rats, grooved-tooth rats and small rodents. Small rodents accounted for almost half of the owls’ diet and when their numbers increased, owls responded by consuming more of them, indicating the importance of farming activities to this population of owls. Other populations of eagle owl inhabiting human-disturbed areas had diet widths positively related to levels of habitat disturbance. This result supported optimal foraging theory that more productive environments have predators with more specialized diets, while patchy environments have generalist predators. The ecology of this population of Mackinder’s eagle owls was heavily influenced by human agricultural activities, which generally had a positive effect on their population. Farming activities changed rapidly both within and between seasons as plots were small and neighbouring farmers planted various crops at different times of the year and this was enhanced by irrigation in some areas. Year-round availability of forage within farms had a positive effect on owl prey species, some of which increased relative to the type and amount of crops found in farms. However, 57% of owl injuries and mortalities that occurred were related either directly or indirectly to human activities. Cultural prejudices against owls remain the biggest threat to this population’s long-term persistence. Farmer education was shown to play a significant role in overcoming negative beliefs about owls. Because Mackinder’s eagle owls are highly adaptable to anthropomorphic landscape changes, largely due to their adaptability as food generalists, they are one of the few top predators remaining in this highly disturbed agricultural system. However, populations within agricultural areas remain especially vulnerable to negative human attitudes towards owls due to their close association with human activities.
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- Date Issued: 2008