The development of trilingual literacy in primary schools in Kenya
- Authors: Mose, Peter N
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/815 , vital:19993
- Description: The Kenyan language in education policy contemplates development of trilingual literacy skills in pupils by the end of standard three. The purpose of this study was to determine to what extent standard three pupils were literate in their mother tongue (Ekegusii), Kiswahili, and English. The study was undertaken in the context of; a language in education policy that provides for the use of mother tongues and Kiswahili (as languages of instruction) in rural and urban schools respectively up to the end of standard three, followed by a transition to an English medium from standard four; a general negative public attitude towards mother tongue instruction; and substantial empirical evidence in support of mother tongue instruction in basic education. Cummins’ Linguistic Interdependence and Linguistic Threshold Hypotheses guided the study. Adopting a mixed methods approach, the study used direct classroom observations, face-to-face interviews, document analyses, and reading tests to obtain data. Thematic, content, and statistical approaches were used in data analysis. It was found that various stakeholders understand key aspects of the language in education policy differently. Secondly, efforts in mother tongue instruction in schools are not motivated by theoretical and empirical foundations; development efforts are hence ineffective and inadequate leaving majority of learners with below average literacy skills in their mother tongue by the end of standard three. Thirdly, teachers do not implement the language in education policy as spelt out in the relevant documents; the three languages have therefore been allocated various classroom functions. Fourthly, the factors that motivate the disregard of the language policy include the language of examinations and textbooks, and transition to standard four in which English is the language of instruction. Lastly, reading scores indicate that majority of pupils transiting to standard four do not possess adequate reading skills to enable them read to learn in a mother tongue, Kiswahili, and English. This is observed across rural, peri-urban, and urban schools. The study recommends that: The ministry of education conducts workshops to re-educate the relevant stakeholders on the meaning and significance of the language in education policy and the significance of mother tongue instruction in second language, literacy, and skill development. This should be followed by a re-classification of primary schools on the basis of linguistic homogeneity, or otherwise, to ensure the intention of the policy is achieved. This could include empowering individual schools to determine language of instruction in lower primary based on language predominance. Secondly, the ministry should provide relevant resources for mother tongues and Kiswahili to develop them as effective languages of instruction as recommended by various past education commission reports. Additionally, a bilingual course in teacher training colleges to equip primary school teachers for bilingualism and biliteracy development should be introduced; one implication of this is teachers giving notes and tests in the languages spelt out in the policy. Thirdly, the ministry should intensify inspection of schools to assess implementation of the policy. Fourthly, future studies should assess mother tongue literacies as well, since they determine the extent and success of second language acquisition and learning; and measures should be put to ensure English is adequately resourced and taught well. Finally, mother tongue instruction should be extended up to, at least, standard five.
- Full Text:
- Date Issued: 2016
- Authors: Mose, Peter N
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/815 , vital:19993
- Description: The Kenyan language in education policy contemplates development of trilingual literacy skills in pupils by the end of standard three. The purpose of this study was to determine to what extent standard three pupils were literate in their mother tongue (Ekegusii), Kiswahili, and English. The study was undertaken in the context of; a language in education policy that provides for the use of mother tongues and Kiswahili (as languages of instruction) in rural and urban schools respectively up to the end of standard three, followed by a transition to an English medium from standard four; a general negative public attitude towards mother tongue instruction; and substantial empirical evidence in support of mother tongue instruction in basic education. Cummins’ Linguistic Interdependence and Linguistic Threshold Hypotheses guided the study. Adopting a mixed methods approach, the study used direct classroom observations, face-to-face interviews, document analyses, and reading tests to obtain data. Thematic, content, and statistical approaches were used in data analysis. It was found that various stakeholders understand key aspects of the language in education policy differently. Secondly, efforts in mother tongue instruction in schools are not motivated by theoretical and empirical foundations; development efforts are hence ineffective and inadequate leaving majority of learners with below average literacy skills in their mother tongue by the end of standard three. Thirdly, teachers do not implement the language in education policy as spelt out in the relevant documents; the three languages have therefore been allocated various classroom functions. Fourthly, the factors that motivate the disregard of the language policy include the language of examinations and textbooks, and transition to standard four in which English is the language of instruction. Lastly, reading scores indicate that majority of pupils transiting to standard four do not possess adequate reading skills to enable them read to learn in a mother tongue, Kiswahili, and English. This is observed across rural, peri-urban, and urban schools. The study recommends that: The ministry of education conducts workshops to re-educate the relevant stakeholders on the meaning and significance of the language in education policy and the significance of mother tongue instruction in second language, literacy, and skill development. This should be followed by a re-classification of primary schools on the basis of linguistic homogeneity, or otherwise, to ensure the intention of the policy is achieved. This could include empowering individual schools to determine language of instruction in lower primary based on language predominance. Secondly, the ministry should provide relevant resources for mother tongues and Kiswahili to develop them as effective languages of instruction as recommended by various past education commission reports. Additionally, a bilingual course in teacher training colleges to equip primary school teachers for bilingualism and biliteracy development should be introduced; one implication of this is teachers giving notes and tests in the languages spelt out in the policy. Thirdly, the ministry should intensify inspection of schools to assess implementation of the policy. Fourthly, future studies should assess mother tongue literacies as well, since they determine the extent and success of second language acquisition and learning; and measures should be put to ensure English is adequately resourced and taught well. Finally, mother tongue instruction should be extended up to, at least, standard five.
- Full Text:
- Date Issued: 2016
The disputed “equitable treatment” in political party broadcasts: an analysis of the SABC coverage of the 2014 South African general elections
- Authors: Ndimande, Dumisani Blessing
- Date: 2016
- Subjects: Elections -- Press coverage -- South Africa , Election monitoring -- South Africa Communication in politics -- South Africa Democracy -- South Africa
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/14234 , vital:27486
- Description: The aim of this study was to establish whether the South African Broadcasting Corporation (SABC) performed according to its mandate in ensuring a fair broadcast coverage of all political parties that participated in the 2014 national general election. The study was undertaken as a result of the complaints by political parties who accused the SABC of bias during the election. The study focused on two SABC radio stations, namely SAFM and UKHOZI FM. In executing the research, particular attention was paid to the coverage of political party manifestos, town hall election debates and radio interviews. The study was written utilising the theoretical paradigm of Social Responsibility Theory, as this is largely deemed the most ethical guide in testing South African journalism. The research was conducted in accordance with the Independent Complaints Authority of South Africa (ICASA) regulations that govern broadcast media during elections. The second part of the analysis deconstructed the SABC’s media coverage of the 2014 election through Media Monitoring Africa – a non-profit organisation that monitors and reports on media coverage of elections, whilst simultaneously taking ICASA stipulated guidelines into account. The MMA and ICASA equipped the study with reports which were compiled after an intense monitoring of SABC’s coverage of the 2014 election. Through the analysis of political parties’ accessibility to the election broadcast programmes on SABC platforms, the study concluded that although there were errors, the SABC treated all parties fairly during the 2014 general elections. The study also found that poor corporate governance at the SABC did not impact directly on the public broadcaster’s ability to deliver fair election broadcasting. By conforming to the social responsibility role that calls for high professional conduct, fairness and objectivity as expected in the public broadcaster, this study found that the SABC was committed to a fair coverage of the 2014 election.
- Full Text:
- Date Issued: 2016
- Authors: Ndimande, Dumisani Blessing
- Date: 2016
- Subjects: Elections -- Press coverage -- South Africa , Election monitoring -- South Africa Communication in politics -- South Africa Democracy -- South Africa
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/14234 , vital:27486
- Description: The aim of this study was to establish whether the South African Broadcasting Corporation (SABC) performed according to its mandate in ensuring a fair broadcast coverage of all political parties that participated in the 2014 national general election. The study was undertaken as a result of the complaints by political parties who accused the SABC of bias during the election. The study focused on two SABC radio stations, namely SAFM and UKHOZI FM. In executing the research, particular attention was paid to the coverage of political party manifestos, town hall election debates and radio interviews. The study was written utilising the theoretical paradigm of Social Responsibility Theory, as this is largely deemed the most ethical guide in testing South African journalism. The research was conducted in accordance with the Independent Complaints Authority of South Africa (ICASA) regulations that govern broadcast media during elections. The second part of the analysis deconstructed the SABC’s media coverage of the 2014 election through Media Monitoring Africa – a non-profit organisation that monitors and reports on media coverage of elections, whilst simultaneously taking ICASA stipulated guidelines into account. The MMA and ICASA equipped the study with reports which were compiled after an intense monitoring of SABC’s coverage of the 2014 election. Through the analysis of political parties’ accessibility to the election broadcast programmes on SABC platforms, the study concluded that although there were errors, the SABC treated all parties fairly during the 2014 general elections. The study also found that poor corporate governance at the SABC did not impact directly on the public broadcaster’s ability to deliver fair election broadcasting. By conforming to the social responsibility role that calls for high professional conduct, fairness and objectivity as expected in the public broadcaster, this study found that the SABC was committed to a fair coverage of the 2014 election.
- Full Text:
- Date Issued: 2016
The drivers of customer satisfaction at National Dairy Equipment (NDE)
- Authors: Laubscher, Ryno
- Date: 2016
- Subjects: Consumer satisfaction Quality of products , SERVQUAL (Service quality framework)
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/13085 , vital:27150
- Description: National Dairy Equipment (Pty) Ltd (NDE) is a privately owned stockist and distributor of stainless steel products and is a respected player in the South African stainless steel industry. NDE operates from within all four major cities in South Africa namely, Johannesburg, Cape Town, Port Elizabeth, and Durban. The organisation, with its wide range of corrosion resistant products, serves industries such as the architecture and construction, automotive, catering, and food and beverage industry. With the stainless steel industry growing in terms of the number of competitors, NDE performs a number of functions in order to achieve customer satisfaction. The general purpose of the study was to indentify the attributes that would act as drivers of customer satisfaction at NDE. Five attributes were identified namely, Service quality, Trust and commitment, Product quality, Commercial aspects and Reliability. The results of this study could assist managers at NDE in improving service delivery to customers. The literature study provided an overview of overall customer satisfaction and possible measurement models for customer satisfaction. Measurement models included, SERVQUAL, SERVPERF, the Two-factor theory, the Kano model and the Three-factor model. The latter proved to be of particular importance to the study as the model was used to classify the identified drivers into basic, performance and excitement factors. Furthermore, a literature review was provided based on each of the identified potential drivers of customer satisfaction. The empirical data needed to complete the study was collected by means of a survey, using a self-administered questionnaire. The questionnaire was distributed by sales representatives at NDE. A total of 320 useable questionnaires were received. The study revealed the following: each of the five proposed attributes had a positive relationship with overall customer satisfaction,thus all five attributes were confirmed as drivers of customer satisfaction at NDE. Commercial aspects and Reliability were classified as basic satisfiers. Trust and commitment was classified as a performance satisfier, and Service quality was identified as the only excitement satisfier. Product quality did not receive any classification. All importance mean scores were higher than the corresponding satisfaction mean scores. This study contributed to the existing body of literature and is seemingly the first of its kind in the South African stainless steel industry. The study is also the first to attempt the measurement of overall customer satisfaction levels at NDE. The methodology used in the current study can be applied to stainless steel industries internationally, in order to verify whether the confirmed drivers would also act as drivers of satisfaction in a similar industry elsewhere in the world.
- Full Text:
- Date Issued: 2016
- Authors: Laubscher, Ryno
- Date: 2016
- Subjects: Consumer satisfaction Quality of products , SERVQUAL (Service quality framework)
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/13085 , vital:27150
- Description: National Dairy Equipment (Pty) Ltd (NDE) is a privately owned stockist and distributor of stainless steel products and is a respected player in the South African stainless steel industry. NDE operates from within all four major cities in South Africa namely, Johannesburg, Cape Town, Port Elizabeth, and Durban. The organisation, with its wide range of corrosion resistant products, serves industries such as the architecture and construction, automotive, catering, and food and beverage industry. With the stainless steel industry growing in terms of the number of competitors, NDE performs a number of functions in order to achieve customer satisfaction. The general purpose of the study was to indentify the attributes that would act as drivers of customer satisfaction at NDE. Five attributes were identified namely, Service quality, Trust and commitment, Product quality, Commercial aspects and Reliability. The results of this study could assist managers at NDE in improving service delivery to customers. The literature study provided an overview of overall customer satisfaction and possible measurement models for customer satisfaction. Measurement models included, SERVQUAL, SERVPERF, the Two-factor theory, the Kano model and the Three-factor model. The latter proved to be of particular importance to the study as the model was used to classify the identified drivers into basic, performance and excitement factors. Furthermore, a literature review was provided based on each of the identified potential drivers of customer satisfaction. The empirical data needed to complete the study was collected by means of a survey, using a self-administered questionnaire. The questionnaire was distributed by sales representatives at NDE. A total of 320 useable questionnaires were received. The study revealed the following: each of the five proposed attributes had a positive relationship with overall customer satisfaction,thus all five attributes were confirmed as drivers of customer satisfaction at NDE. Commercial aspects and Reliability were classified as basic satisfiers. Trust and commitment was classified as a performance satisfier, and Service quality was identified as the only excitement satisfier. Product quality did not receive any classification. All importance mean scores were higher than the corresponding satisfaction mean scores. This study contributed to the existing body of literature and is seemingly the first of its kind in the South African stainless steel industry. The study is also the first to attempt the measurement of overall customer satisfaction levels at NDE. The methodology used in the current study can be applied to stainless steel industries internationally, in order to verify whether the confirmed drivers would also act as drivers of satisfaction in a similar industry elsewhere in the world.
- Full Text:
- Date Issued: 2016
The dynamics of microalgal communities in response to environmental variables and nutrient fluxes in ephemeral wetlands in the Nelson Mandela Bay Metropole
- Authors: Lategan, Jodi
- Date: 2016
- Subjects: Vernal pool ecology -- South Africa -- Nelson Mandela Bay Municipality Vernal pools -- South Africa -- Nelson Mandela Bay Municipality. , patial ecology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13138 , vital:27155
- Description: Ephemeral wetlands provide numerous ecosystem services, but are disappearing due to urbanisation and habitat fragmentation. Knowledge is required to conserve these systems, but ephemeral wetland research in South Africa is lacking. As primary producers, microalgae provide a key link between the biotic and abiotic components of aquatic ecosystems. Despite their importance, there is a paucity in information concerning microalgal dynamics in ephemeral wetlands. The aim of this study was to understand the spatial and temporal dynamics of microalgae in ephemeral wetlands of the Nelson Mandela Bay Metropole. The research followed a funnel-based approach that assessed 35 wetlands at a regional level, followed by a temporal assessment of six wetlands, monitored biweekly, monthly or quarterly. Thereafter, a case study at local scale was carried out to address wetland connectivity and Hydrogeomorphic unit trends. The research culminated in a benthic flux chamber experiment, addressing the influence of microalgal-mediated processes on wetland development for a month post inundation. Phytoplankton biomass showed strong regional associations with rainfall zone, with Chl a concentrations of 17; 4.6; and 25 µg.L-1 in the high, intermediate and low rainfall zones, respectively. The MPB communities in Seeps, Depressions and Wetland flats, comprised between 45 and 60 % diatoms, whilst other microalgal groups were dominant in the water columns (> 90 %). Phytoplankton and MPB interactions facilitated significant night-time NH4+ and SRP effluxes, (1.5 and 0.4 mg.m-2.h-1, respectively) four days post inundation. High Silica uptake in the latter stages, was attributed to an increase in diatom abundance. Within the chambers, MPB growth was continuous whilst phytoplankton exhibited cyclical growth as the system approached dynamic equilibrium. This study demonstrated the importance of nutrient cycling in structuring aquatic food webs, and indicated the sensitivity of ephemeral wetlands to environmental perturbations.
- Full Text:
- Date Issued: 2016
- Authors: Lategan, Jodi
- Date: 2016
- Subjects: Vernal pool ecology -- South Africa -- Nelson Mandela Bay Municipality Vernal pools -- South Africa -- Nelson Mandela Bay Municipality. , patial ecology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13138 , vital:27155
- Description: Ephemeral wetlands provide numerous ecosystem services, but are disappearing due to urbanisation and habitat fragmentation. Knowledge is required to conserve these systems, but ephemeral wetland research in South Africa is lacking. As primary producers, microalgae provide a key link between the biotic and abiotic components of aquatic ecosystems. Despite their importance, there is a paucity in information concerning microalgal dynamics in ephemeral wetlands. The aim of this study was to understand the spatial and temporal dynamics of microalgae in ephemeral wetlands of the Nelson Mandela Bay Metropole. The research followed a funnel-based approach that assessed 35 wetlands at a regional level, followed by a temporal assessment of six wetlands, monitored biweekly, monthly or quarterly. Thereafter, a case study at local scale was carried out to address wetland connectivity and Hydrogeomorphic unit trends. The research culminated in a benthic flux chamber experiment, addressing the influence of microalgal-mediated processes on wetland development for a month post inundation. Phytoplankton biomass showed strong regional associations with rainfall zone, with Chl a concentrations of 17; 4.6; and 25 µg.L-1 in the high, intermediate and low rainfall zones, respectively. The MPB communities in Seeps, Depressions and Wetland flats, comprised between 45 and 60 % diatoms, whilst other microalgal groups were dominant in the water columns (> 90 %). Phytoplankton and MPB interactions facilitated significant night-time NH4+ and SRP effluxes, (1.5 and 0.4 mg.m-2.h-1, respectively) four days post inundation. High Silica uptake in the latter stages, was attributed to an increase in diatom abundance. Within the chambers, MPB growth was continuous whilst phytoplankton exhibited cyclical growth as the system approached dynamic equilibrium. This study demonstrated the importance of nutrient cycling in structuring aquatic food webs, and indicated the sensitivity of ephemeral wetlands to environmental perturbations.
- Full Text:
- Date Issued: 2016
The dynamics of police regulation of sexual abuse of children in South Africa: the case of Grahamstown, Eastern Cape
- Authors: Van Blerk, Natasha
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3828 , vital:20546
- Description: This thesis investigates the current legislation and police protocols set in South Africa, specifically regarding their adequacy in protecting the country’s children from sexual abuse. It focuses on relevant legislative provisions and protocols, on sexual abuse of children and on an empirical study conducted amongst a variety of officials who represent the South African legislation at different levels. Trends, developments and problems are analysed and brought forward to raise an awareness on the severity of the issue of child sexual abuse. In addition, this thesis explores how the diversity within the community of Grahamstown, South Africa, should be considered to a higher degree in the legislation. There is a clear indication of a prevalent patriarchal hierarchy within the community which, in reality, makes women and children more vulnerable to sexual abuse. The methods used in this thesis involves purposive sampling, which led to one on one interviews between the researcher and participant. Thisthesis concludes with confirmation of the hypothesis whereby the South African legislation is not adequately protecting the rights of children in regards to sexual abuse. However, to fully adapt the legislation and make it as versatile and as effective the State hopes it to be, it is necessary to understand the society’s perception on women and children and to rectify it. As difficult as this may sound, it all begins with a strong and influential government.
- Full Text:
- Date Issued: 2016
- Authors: Van Blerk, Natasha
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: http://hdl.handle.net/10962/3828 , vital:20546
- Description: This thesis investigates the current legislation and police protocols set in South Africa, specifically regarding their adequacy in protecting the country’s children from sexual abuse. It focuses on relevant legislative provisions and protocols, on sexual abuse of children and on an empirical study conducted amongst a variety of officials who represent the South African legislation at different levels. Trends, developments and problems are analysed and brought forward to raise an awareness on the severity of the issue of child sexual abuse. In addition, this thesis explores how the diversity within the community of Grahamstown, South Africa, should be considered to a higher degree in the legislation. There is a clear indication of a prevalent patriarchal hierarchy within the community which, in reality, makes women and children more vulnerable to sexual abuse. The methods used in this thesis involves purposive sampling, which led to one on one interviews between the researcher and participant. Thisthesis concludes with confirmation of the hypothesis whereby the South African legislation is not adequately protecting the rights of children in regards to sexual abuse. However, to fully adapt the legislation and make it as versatile and as effective the State hopes it to be, it is necessary to understand the society’s perception on women and children and to rectify it. As difficult as this may sound, it all begins with a strong and influential government.
- Full Text:
- Date Issued: 2016
The ecology of hard substrate communities around Sardinia Bay in the warm-temperate Agulhas Bioregion
- Authors: Evans, Adrian G , Nel, Ronel
- Date: 2016
- Subjects: Aquatic biodiversity -- South Africa -- Nelson Mandela Bay Municipality , Marine ecology -- South Africa -- Nelson Mandela Bay Municipality , Seashore biology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6782 , vital:21141
- Description: Hard substrates in the marine environment are an important ecosystem of great scientific and economic value. Hard substrates provide suitable habitat for a diverse assemblage of benthic organisms. This thesis investigated the ecology of benthic hard substrate communities along a section of wave-exposed coastline, including the Sardinia Bay Marine Protected Area (MPA), in the warm-temperate Agulhas bioregion of South Africa. The effect of physical variables on benthic communities, including both the intertidal and shallow subtidal, was quantitatively assessed across (Chapter 3) and along (Chapter 4) the shore to provide a model of zonation for this bioregion and a baseline of community patters and biodiversity, as this information was lacking especially for the Sardinia Bay MPA. The zones described in Chapter 3 were in agreement with previous trends described for this bioregion with the addition of different biotopes in the upper Balanoid and deeper subtidal zones as well as the addition of an intermediate/transition zone in the subtidal between the algal dominated shallow subtidal and deeper subtidal, which has an increased abundance of sessile invertebrates. Disturbance is an important process in structuring benthic communities, and its role in structuring shallow benthic communities was investigated using a disturbance simulation experiment across a wave-exposure gradient (Chapter 5). Communities were found to change along the exposure gradient and monitoring the undisturbed communities showed that large waves caused disturbances across all the exposures. The recovery process was similar across all exposures mainly through lateral vegetative growth and regrowth from basal parts with communities in disturbed quadrats recovering to resemble the surrounding undisturbed community. Recruitment did not have a significant effect in the recovery process and community composition was therefore a result of the effects of the physical environment along the exposure gradient. Lastly this thesis investigated the indirect effects of protection in the small Sardinia Bay MPA (Chapter 6). Despite the small size of the MPA this study found differences in diversity and abundance between communities inside and outside the MPA. These differences in benthic biota infer indirect effects of protection that are probably due to the increase in abundance of exploited fish inside the MPA. Lower abundances of red algae, macroinvertebrates and diversity inside the MPA in the shallow depth category was attributed to the higher abundance of the generalist fish species that concentrate in the shallows. Significantly lower abundances of Chordata in the shallow and medium depth categories inside the MPA was attributed to predation by the benthic carnivorous species as ascidians are included in the diet of these species. This chapter also compared the effectiveness of destructive (scraped quadrats) and non-destructive (visually assessed quadrats) sampling methods. Scraped quadrats were found to be more effective in detecting changes across the MPA compared to visually assessed quadrats. Destructive methods sample the entire assemblage, to a higher taxonomic level, and measure abundance using biomass. It was concluded that biomass is a better metric when comparing communities across protection or other treatments as it provides better biological information of the community.
- Full Text:
- Date Issued: 2016
- Authors: Evans, Adrian G , Nel, Ronel
- Date: 2016
- Subjects: Aquatic biodiversity -- South Africa -- Nelson Mandela Bay Municipality , Marine ecology -- South Africa -- Nelson Mandela Bay Municipality , Seashore biology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/6782 , vital:21141
- Description: Hard substrates in the marine environment are an important ecosystem of great scientific and economic value. Hard substrates provide suitable habitat for a diverse assemblage of benthic organisms. This thesis investigated the ecology of benthic hard substrate communities along a section of wave-exposed coastline, including the Sardinia Bay Marine Protected Area (MPA), in the warm-temperate Agulhas bioregion of South Africa. The effect of physical variables on benthic communities, including both the intertidal and shallow subtidal, was quantitatively assessed across (Chapter 3) and along (Chapter 4) the shore to provide a model of zonation for this bioregion and a baseline of community patters and biodiversity, as this information was lacking especially for the Sardinia Bay MPA. The zones described in Chapter 3 were in agreement with previous trends described for this bioregion with the addition of different biotopes in the upper Balanoid and deeper subtidal zones as well as the addition of an intermediate/transition zone in the subtidal between the algal dominated shallow subtidal and deeper subtidal, which has an increased abundance of sessile invertebrates. Disturbance is an important process in structuring benthic communities, and its role in structuring shallow benthic communities was investigated using a disturbance simulation experiment across a wave-exposure gradient (Chapter 5). Communities were found to change along the exposure gradient and monitoring the undisturbed communities showed that large waves caused disturbances across all the exposures. The recovery process was similar across all exposures mainly through lateral vegetative growth and regrowth from basal parts with communities in disturbed quadrats recovering to resemble the surrounding undisturbed community. Recruitment did not have a significant effect in the recovery process and community composition was therefore a result of the effects of the physical environment along the exposure gradient. Lastly this thesis investigated the indirect effects of protection in the small Sardinia Bay MPA (Chapter 6). Despite the small size of the MPA this study found differences in diversity and abundance between communities inside and outside the MPA. These differences in benthic biota infer indirect effects of protection that are probably due to the increase in abundance of exploited fish inside the MPA. Lower abundances of red algae, macroinvertebrates and diversity inside the MPA in the shallow depth category was attributed to the higher abundance of the generalist fish species that concentrate in the shallows. Significantly lower abundances of Chordata in the shallow and medium depth categories inside the MPA was attributed to predation by the benthic carnivorous species as ascidians are included in the diet of these species. This chapter also compared the effectiveness of destructive (scraped quadrats) and non-destructive (visually assessed quadrats) sampling methods. Scraped quadrats were found to be more effective in detecting changes across the MPA compared to visually assessed quadrats. Destructive methods sample the entire assemblage, to a higher taxonomic level, and measure abundance using biomass. It was concluded that biomass is a better metric when comparing communities across protection or other treatments as it provides better biological information of the community.
- Full Text:
- Date Issued: 2016
The effect of Acacia karroo tree density on grass species composition, forage yield and quality in different rainfall regimes in the Eastern Cape, South Africa
- Authors: De Ridder, Cornelius Henry
- Date: 2016
- Subjects: Grasses -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2858 , vital:20357
- Description: It is widely believed that Acacia karroo Hayne trees compete with and negatively affect the production of grasses in their immediate surroundings. This perception formed as a result of observations by farmers of their veld as well as some research. The complexity of plant interactions in different conditions required that research be done to better explain the extent of grass and tree interactions. In response to this need, the effect of a range of Acacia karroo densities on grass production was tested in areas of differing rainfall. Results emphasize the complexity of such plant interactions but highlight rainfall as influencing the effect of tree density on grass production and grass quality. Study sites were chosen with significant differences in tree density and rainfall and this was found to be concomitant with significant differences in grass yield and crude protein (p < 0.001). Grass yield (mass produced) was negatively correlated with tree density (p < 0.001) and was affected by rainfall. High tree density reduced grass yield at the lower rainfall sites, but a reduction in yield was only recorded during dry conditions in the higher rainfall areas. By contrast, the crude protein content of grasses was positively correlated to tree density (p < 0.001). However, as with yield, rainfall played an important part in the strength of the correlation. Soil properties such as temperature (-) (p = 0.011), phosphorus content (+) (p = 0.006), calcium concentration (+) (p = 0.005), acid saturation (-) (p = 0.018), and soil pH (+) (p = 0.008) were also significantly correlated to tree density. Tree density enriched the soil, subsequently benefitting grass quality. The study sites investigated, had different plant communities and environmental conditions with Cradock, Kubusi Drift and Kei Mouth having unique communities and conditions while Adelaide and Cathcart could not be separated in either. Cradock was the driest site and the vegetation was dominated by both grasses and karroid shrubs, differing in pattern and process from the other sites. The Kubusi Drift site had high tree densities, to the extent that the trees altered the grass species composition. The effects of rainfall on grass yield and quality exceeded that of community composition differences.
- Full Text:
- Date Issued: 2016
- Authors: De Ridder, Cornelius Henry
- Date: 2016
- Subjects: Grasses -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2858 , vital:20357
- Description: It is widely believed that Acacia karroo Hayne trees compete with and negatively affect the production of grasses in their immediate surroundings. This perception formed as a result of observations by farmers of their veld as well as some research. The complexity of plant interactions in different conditions required that research be done to better explain the extent of grass and tree interactions. In response to this need, the effect of a range of Acacia karroo densities on grass production was tested in areas of differing rainfall. Results emphasize the complexity of such plant interactions but highlight rainfall as influencing the effect of tree density on grass production and grass quality. Study sites were chosen with significant differences in tree density and rainfall and this was found to be concomitant with significant differences in grass yield and crude protein (p < 0.001). Grass yield (mass produced) was negatively correlated with tree density (p < 0.001) and was affected by rainfall. High tree density reduced grass yield at the lower rainfall sites, but a reduction in yield was only recorded during dry conditions in the higher rainfall areas. By contrast, the crude protein content of grasses was positively correlated to tree density (p < 0.001). However, as with yield, rainfall played an important part in the strength of the correlation. Soil properties such as temperature (-) (p = 0.011), phosphorus content (+) (p = 0.006), calcium concentration (+) (p = 0.005), acid saturation (-) (p = 0.018), and soil pH (+) (p = 0.008) were also significantly correlated to tree density. Tree density enriched the soil, subsequently benefitting grass quality. The study sites investigated, had different plant communities and environmental conditions with Cradock, Kubusi Drift and Kei Mouth having unique communities and conditions while Adelaide and Cathcart could not be separated in either. Cradock was the driest site and the vegetation was dominated by both grasses and karroid shrubs, differing in pattern and process from the other sites. The Kubusi Drift site had high tree densities, to the extent that the trees altered the grass species composition. The effects of rainfall on grass yield and quality exceeded that of community composition differences.
- Full Text:
- Date Issued: 2016
The effect of bond market on economic growth in South Africa
- Authors: Dingela, Siyasanga
- Date: 2016
- Subjects: Bond market -- South Africa , Economic development -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/7218 , vital:21306
- Description: This paper investigates the effect of bond market on economic growth in South Africa. Quarterly data for South Africa for the period 2003-2014 was used to develop a general- to- specific Auto-Regressive Distribution Lag (ARDL) approach. The empirical results confirm that there is a positive relationship between Bond market and economic growth in South Africa. A co-integrated relationship between economic growth, stock market and banking sector was noticed in both the long-run and short-runs.
- Full Text:
- Date Issued: 2016
- Authors: Dingela, Siyasanga
- Date: 2016
- Subjects: Bond market -- South Africa , Economic development -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/7218 , vital:21306
- Description: This paper investigates the effect of bond market on economic growth in South Africa. Quarterly data for South Africa for the period 2003-2014 was used to develop a general- to- specific Auto-Regressive Distribution Lag (ARDL) approach. The empirical results confirm that there is a positive relationship between Bond market and economic growth in South Africa. A co-integrated relationship between economic growth, stock market and banking sector was noticed in both the long-run and short-runs.
- Full Text:
- Date Issued: 2016
The effect of different land uses on household livelihoods in Tale Ga-Morudu Communal Property Association
- Authors: Ramaloko, Thomas Tshwantshi
- Date: 2016
- Subjects: Land use -- South Africa -- Limpopo Reparations for historical injustices -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , PhD
- Identifier: http://hdl.handle.net/10948/14146 , vital:27436
- Description: This study is about a population of 235 households in Blouberg municipality, Limpopo Province, that constituted itself in 2004 into a Communal Property Association. The Tale Ga-Morudu CPA was formed in order to own, manage and control a total of seventeen farms which were progressively restituted to them during 2004 by the Commission on Restitution of Land Rights. Tale Ga-Morudu households were dispossessed and forcefully removed from a number of fertile, arable and irrigable farms1in the 1960s due to racially discriminatory laws or practices. These households were then relocated by the then apartheid regime on the eastern part of Mogalakwena River. They were distributed in the arid communal areas of Laanglagte/Vergelegen, Matekereng; Ga- Mankgodi; Letswatla and Mamoleka under the traditional leadership of Kgoshi Maleboho of BabinaTšhwene. (Map one). It is the aim of this study to find out how Tale Ga-Morudu CPA currently uses these restituted farms for the households who have said to have benefited from restituted land. The researcher used his own observations, lessons and analysis of perspectives from case studies conducted from Limpopo in order to pursue this aim. This study adopted a descriptive household survey design that used a predominantly quantitative approach, and the use of qualitative methods to complement contextual details. A quantitative questionnaire was used on a sample unit of (20%) 45 households obtained by simple random sampling from a population of 235 households of the CPA. Other qualitative methods include focus group discussion, document review and observation. From the results it is clear that land claimants, prefer to retain existing practices of land use, than risk changes in land use in order to meet their socio-economic needs. Thus, instead of investing in commercial agriculture or wildlife farming, people follow subsistence agriculture and remain dependent on social grants and pensions for their livelihood. The general study findings show that the CPA planned to implement different types of land use including those of direct land use value. These include food gardens, resettlement; game farming; poultry enterprises and livestock grazing, and also of indirect use value. The latter refers to contract crop cultivation, rentals and strategic partnerships. The study found that despite income being generated from indirect types of land use, the majority of these intended beneficiaries never benefited from accrued financial dividends of land rental and development. However, households were still able to take advantage of employment opportunities created by contract crop cultivation and in the process they acquired crop cultivation skills. Furthermore the harvesting of natural resources such as wood and poles also contribute to the wellness of households. Households, also derived cultural wellness and a sense of satisfaction by accessing their restored farms to perform rituals. The general conclusion of the study is that the CPA is underutilizing its properties, including arable and irrigable fields, rentable recreational facilities, game farming and its tourism potential.
- Full Text:
- Date Issued: 2016
- Authors: Ramaloko, Thomas Tshwantshi
- Date: 2016
- Subjects: Land use -- South Africa -- Limpopo Reparations for historical injustices -- South Africa -- Limpopo
- Language: English
- Type: Thesis , Masters , PhD
- Identifier: http://hdl.handle.net/10948/14146 , vital:27436
- Description: This study is about a population of 235 households in Blouberg municipality, Limpopo Province, that constituted itself in 2004 into a Communal Property Association. The Tale Ga-Morudu CPA was formed in order to own, manage and control a total of seventeen farms which were progressively restituted to them during 2004 by the Commission on Restitution of Land Rights. Tale Ga-Morudu households were dispossessed and forcefully removed from a number of fertile, arable and irrigable farms1in the 1960s due to racially discriminatory laws or practices. These households were then relocated by the then apartheid regime on the eastern part of Mogalakwena River. They were distributed in the arid communal areas of Laanglagte/Vergelegen, Matekereng; Ga- Mankgodi; Letswatla and Mamoleka under the traditional leadership of Kgoshi Maleboho of BabinaTšhwene. (Map one). It is the aim of this study to find out how Tale Ga-Morudu CPA currently uses these restituted farms for the households who have said to have benefited from restituted land. The researcher used his own observations, lessons and analysis of perspectives from case studies conducted from Limpopo in order to pursue this aim. This study adopted a descriptive household survey design that used a predominantly quantitative approach, and the use of qualitative methods to complement contextual details. A quantitative questionnaire was used on a sample unit of (20%) 45 households obtained by simple random sampling from a population of 235 households of the CPA. Other qualitative methods include focus group discussion, document review and observation. From the results it is clear that land claimants, prefer to retain existing practices of land use, than risk changes in land use in order to meet their socio-economic needs. Thus, instead of investing in commercial agriculture or wildlife farming, people follow subsistence agriculture and remain dependent on social grants and pensions for their livelihood. The general study findings show that the CPA planned to implement different types of land use including those of direct land use value. These include food gardens, resettlement; game farming; poultry enterprises and livestock grazing, and also of indirect use value. The latter refers to contract crop cultivation, rentals and strategic partnerships. The study found that despite income being generated from indirect types of land use, the majority of these intended beneficiaries never benefited from accrued financial dividends of land rental and development. However, households were still able to take advantage of employment opportunities created by contract crop cultivation and in the process they acquired crop cultivation skills. Furthermore the harvesting of natural resources such as wood and poles also contribute to the wellness of households. Households, also derived cultural wellness and a sense of satisfaction by accessing their restored farms to perform rituals. The general conclusion of the study is that the CPA is underutilizing its properties, including arable and irrigable fields, rentable recreational facilities, game farming and its tourism potential.
- Full Text:
- Date Issued: 2016
The effect of English as a medium of instruction on the academic performance of students in life orientation at Dower Campus of the Port Elizabeth College
- Authors: Magxaki, Akhona
- Date: 2016
- Subjects: English language -- Study and teaching (Higher) -- South Africa -- Port Elizabeth English language -- Ability testing -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/14697 , vital:27825
- Description: South Africa is a country with 11 official languages including English. English, however, dominates the educational sector, as medium of instruction. This is despite a plethora of research that shows the cognitive advantages of mother tongue instruction and language policies that promote additive bilingual approaches. As subtractive language approaches characterise poor schooling contexts, the outcomes for students are poor. This is because they do not develop proficiency in any language. The abolition of apartheid in South Africa and the advent of democracy in 1994 resulted in dramatic changes in the education system. Nevertheless, the medium of instruction from Grade four has remained English. Consequently, for the majority of the population the education is in their second language. This study takes place in the higher education setting of a TVET college, namely the Dower Campus in Port Elizabeth. It focuses specifically on Level 2 (first year) Life Orientation students to consider the effect English has, as medium of instruction, on the academic performance of students. There is concern about the status of TVET colleges. Even though the higher education sector has transformed, these skills based colleges are still given inferior status in the eyes of the general public and students themselves. These students may be particularly at risk of success given that they have lower entry requirements than other students in the higher education sector. The subject Life Orientation was used to examine the effect of English on student performance. Life Orientation has come under scrutiny for its usefulness and it cognitive value. This study argues that it is a valuable subject for students at colleges, equipping them with knowledge to succeed at studies and in society at large. However, the pass rates for Life Orientation have been consistently low. The study wanted to probe the role of English in this performance. To address the aims and objectives of this study, relevant literature and various multilingual approaches were reviewed to determine which strategies might be most effective in helping students cope with English as medium of instruction. The study also presents a case for the development of indigenous languages as medium of instruction. The study used a mixed methods approach, that is both qualitative and quantitative methods, to explore the use, attitude and perceptions of English among lecturers and students. The research used an interpretive approach and the study took the form of a case study. The researcher took the stance of being a non-participant observer. Qualitative data was obtained through the use of interviews while quantitative data was obtained through the use of questionnaires. The interviews were recorded and transcribed by a transcriber. Data was analysed using a thematic approach. The results showed that majority of the students did not speak English frequently nor had it as a home language yet they all had a positive regard for the language. Many factors were responsible for student performance in Life Orientation such as attitude to subject, theoretical versus practical components of the subject and student background. However, the medium of instruction played a large role in this performance. Though lecturers foregrounded the importance of English as medium of instruction, they recognise that it was a barrier to understanding and affected student performance. Analysis of the lecturer interviews and the questionnaires with students revealed that students were experiencing difficulty speaking, reading and writing in English. Lecturers adapted their teaching strategies when teaching by including translanguaging strategies of code-switching to facilitate understanding. The data also indicated that code switching was considered by the lecturers to be the most suitable method in teaching to student. Code-meshing and written translations of material were not strategies employed by lecturers. Students indicated that they would prefer to write assignments drafts initially in mother tongue. The findings also suggested that it was necessary for the lecturer to use a variety of multilingual strategies to ensure that students enjoy success in Life Orientation. Based on the findings, this study makes recommendations regarding the teaching and learning of English to students which includes the use of multilingual classroom strategies, collaboration with language lecturers and development of a multilingual language policy to aid in the understanding and acquisition of English terminology used in LO content. Such a language policy should also seek to develop indigenous languages as mediums of instructions at the college.
- Full Text:
- Date Issued: 2016
- Authors: Magxaki, Akhona
- Date: 2016
- Subjects: English language -- Study and teaching (Higher) -- South Africa -- Port Elizabeth English language -- Ability testing -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/14697 , vital:27825
- Description: South Africa is a country with 11 official languages including English. English, however, dominates the educational sector, as medium of instruction. This is despite a plethora of research that shows the cognitive advantages of mother tongue instruction and language policies that promote additive bilingual approaches. As subtractive language approaches characterise poor schooling contexts, the outcomes for students are poor. This is because they do not develop proficiency in any language. The abolition of apartheid in South Africa and the advent of democracy in 1994 resulted in dramatic changes in the education system. Nevertheless, the medium of instruction from Grade four has remained English. Consequently, for the majority of the population the education is in their second language. This study takes place in the higher education setting of a TVET college, namely the Dower Campus in Port Elizabeth. It focuses specifically on Level 2 (first year) Life Orientation students to consider the effect English has, as medium of instruction, on the academic performance of students. There is concern about the status of TVET colleges. Even though the higher education sector has transformed, these skills based colleges are still given inferior status in the eyes of the general public and students themselves. These students may be particularly at risk of success given that they have lower entry requirements than other students in the higher education sector. The subject Life Orientation was used to examine the effect of English on student performance. Life Orientation has come under scrutiny for its usefulness and it cognitive value. This study argues that it is a valuable subject for students at colleges, equipping them with knowledge to succeed at studies and in society at large. However, the pass rates for Life Orientation have been consistently low. The study wanted to probe the role of English in this performance. To address the aims and objectives of this study, relevant literature and various multilingual approaches were reviewed to determine which strategies might be most effective in helping students cope with English as medium of instruction. The study also presents a case for the development of indigenous languages as medium of instruction. The study used a mixed methods approach, that is both qualitative and quantitative methods, to explore the use, attitude and perceptions of English among lecturers and students. The research used an interpretive approach and the study took the form of a case study. The researcher took the stance of being a non-participant observer. Qualitative data was obtained through the use of interviews while quantitative data was obtained through the use of questionnaires. The interviews were recorded and transcribed by a transcriber. Data was analysed using a thematic approach. The results showed that majority of the students did not speak English frequently nor had it as a home language yet they all had a positive regard for the language. Many factors were responsible for student performance in Life Orientation such as attitude to subject, theoretical versus practical components of the subject and student background. However, the medium of instruction played a large role in this performance. Though lecturers foregrounded the importance of English as medium of instruction, they recognise that it was a barrier to understanding and affected student performance. Analysis of the lecturer interviews and the questionnaires with students revealed that students were experiencing difficulty speaking, reading and writing in English. Lecturers adapted their teaching strategies when teaching by including translanguaging strategies of code-switching to facilitate understanding. The data also indicated that code switching was considered by the lecturers to be the most suitable method in teaching to student. Code-meshing and written translations of material were not strategies employed by lecturers. Students indicated that they would prefer to write assignments drafts initially in mother tongue. The findings also suggested that it was necessary for the lecturer to use a variety of multilingual strategies to ensure that students enjoy success in Life Orientation. Based on the findings, this study makes recommendations regarding the teaching and learning of English to students which includes the use of multilingual classroom strategies, collaboration with language lecturers and development of a multilingual language policy to aid in the understanding and acquisition of English terminology used in LO content. Such a language policy should also seek to develop indigenous languages as mediums of instructions at the college.
- Full Text:
- Date Issued: 2016
The effect of foreign direct investment on economic growth in South Africa
- Authors: Mbeki, Zizipho
- Date: 2016
- Subjects: Public investments -- South Africa Economic development -- South Africa , Investments
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/11166 , vital:26890
- Description: The effect of FDI on economic growth is not a straight jacket. Literature has shown that the effect of FDI on economic growth can be either positive or negative. The positive effects of FDI can be caused by increase in output stimulated by new technological innovations and increase in capital flows. The negative effects could result in a ‘crowding out’ effect on domestic investments, external vulnerability and dependence, destructive competition of foreign affiliates with domestic firms, and market stealing effect due to poor absorptive capacity.This treatise will attempt to shed light on the effect foreign direct investment has on economic growth in South Africa in order to ascertain whether a positive or negative relationship exists between these two variables. This study thus aims to investigate, analyse and estimate the extent to which FDI impacts economic growth in South Africa. The findings of this research will provide policymakers, commercial businesses and scholars with relevant updated theoretical and empirical results that will assist relevant government policy makers in generating effective measures of attracting FDI if it proves to be beneficial for the host country. If the results of the study prove that FDIs do not generate positive spill over effects then the policymakers are thus obliged to formulate policies that will discourage FDIs from penetrating the host country’s economy.
- Full Text:
- Date Issued: 2016
- Authors: Mbeki, Zizipho
- Date: 2016
- Subjects: Public investments -- South Africa Economic development -- South Africa , Investments
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/11166 , vital:26890
- Description: The effect of FDI on economic growth is not a straight jacket. Literature has shown that the effect of FDI on economic growth can be either positive or negative. The positive effects of FDI can be caused by increase in output stimulated by new technological innovations and increase in capital flows. The negative effects could result in a ‘crowding out’ effect on domestic investments, external vulnerability and dependence, destructive competition of foreign affiliates with domestic firms, and market stealing effect due to poor absorptive capacity.This treatise will attempt to shed light on the effect foreign direct investment has on economic growth in South Africa in order to ascertain whether a positive or negative relationship exists between these two variables. This study thus aims to investigate, analyse and estimate the extent to which FDI impacts economic growth in South Africa. The findings of this research will provide policymakers, commercial businesses and scholars with relevant updated theoretical and empirical results that will assist relevant government policy makers in generating effective measures of attracting FDI if it proves to be beneficial for the host country. If the results of the study prove that FDIs do not generate positive spill over effects then the policymakers are thus obliged to formulate policies that will discourage FDIs from penetrating the host country’s economy.
- Full Text:
- Date Issued: 2016
The effect of interest rates on investment spending: an empirical analysis of South Africa
- Authors: Dakin, Nicholas John
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1131 , http://hdl.handle.net/10962/d1021174
- Description: This thesis investigates the nature and strength of the relationship between short-, medium-, and long-term real interest rates and capital investment spending at both the aggregate and disaggregate levels in South Africa in order to determine whether changes in the real interest rate affect the level of capital investment in the economy. This thesis used quarterly data for the period 1987 to 2013. VAR modelling, variance decompositions, impulse response functions and Granger causality tests are used to explore the nature and strength of the relationship between interest rates and investment spending. It is found that interest rates explain very little of the variation in investment spending and seem to have little impact on investment (of any type). Furthermore, short-, medium- and long-term interest rates have different effects on the level of investment spending. A rise in short-term interest rates appears to decrease the level of investment spending in the long-run, whereas a rise in long-term interest rates results in an increase in investment.
- Full Text:
- Date Issued: 2016
- Authors: Dakin, Nicholas John
- Date: 2016
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1131 , http://hdl.handle.net/10962/d1021174
- Description: This thesis investigates the nature and strength of the relationship between short-, medium-, and long-term real interest rates and capital investment spending at both the aggregate and disaggregate levels in South Africa in order to determine whether changes in the real interest rate affect the level of capital investment in the economy. This thesis used quarterly data for the period 1987 to 2013. VAR modelling, variance decompositions, impulse response functions and Granger causality tests are used to explore the nature and strength of the relationship between interest rates and investment spending. It is found that interest rates explain very little of the variation in investment spending and seem to have little impact on investment (of any type). Furthermore, short-, medium- and long-term interest rates have different effects on the level of investment spending. A rise in short-term interest rates appears to decrease the level of investment spending in the long-run, whereas a rise in long-term interest rates results in an increase in investment.
- Full Text:
- Date Issued: 2016
The effect of kelp supplementation in formulated feed on the production performance and gut microbiota of South African abalone (Haliotis midae)
- Authors: Nel, Aldi
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/899 , vital:20001
- Description: Formulated feeds with a relatively low (< 5 % of dry mass) kelp (Ecklonia maxima) inclusion level are widely used on commercial abalone (Haliotis midae) farms in South Africa. Although the use of kelp, a major constituent of the natural diet of H. midae, as a dietary supplement is considered to enhance abalone growth and feed utilisation, there are no published studies which quantify the effects of kelp inclusion in formulated feeds. Furthermore, the physiological mechanisms by which kelp supplementation may positively influence abalone digestive physiology and growth are largely unknown. As the kelp supplement is comprised mostly of soluble fibres and abalone gut bacteria associated with macroalgae (and its fibrous polysaccharides) are known to play a key role in digestion, it was hypothesised that the kelp supplement influences the gut-bacterial community profiles of cultured abalone through prebiotic and other metabolic effects. The present thesis thus examined the effect of kelp supplementation on the performance of abalone (Haliotis midae) fed formulated feeds and explored the influence of a kelp supplement on the abalone gut microbiota and its function in the gastrointestinal tract. The key hypotheses of the study were that kelp supplementation in formulated feed: 1) enhances abalone growth; 2) causes a shift in abalone gut-bacterial community composition through a prebiotic-like effect; 3) may induce changes in crop morphology as a result of potential bacterial-associated increases in volatile short-chain fatty acids, and 4) alters digestive enzyme activities in the abalone gut through changes in bacterial-derived (exogenous) digestive enzymes. The growth-promoting efficacy of low-level kelp supplementation was tested by feeding isonitrogenous and isoenergetic experimental feeds containing 0.00 – 3.54 % kelp (dry mass) to sub-adult abalone (~43 mm shell length) for eight months under commercial farm conditions. The growth trial established that kelp supplementation (0.44 – 3.54 % of dry mass) promoted faster growth and improved feed conversion and protein efficiency ratios in cultured abalone compared to abalone fed the non-supplemented control diet, while there were no significant differences in growth for abalone fed the different kelp-supplemented diets (0.44, 0.88, 1.76 and 3.54 % of dry mass). Feed conversion and protein efficiency ratios displayed significant correlations with kelp level in the range of 0.00 – 3.54 % dry mass, and it is therefore recommended that kelp be included in the formulated feeds of cultured South African abalone at a rate of up to 3.54 % of dry mass. A kelp-supplemented (0.88 % dry weight inclusion) feed was fed to abalone under farm conditions to compare gut physiological parameters (crop morphology, digestive enzyme activities and the gut microbiota) in abalone against that of abalone fed an isonitrogenous and isoenergetic non-supplemented control feed. To establish if the observed higher abalone growth rates were related to improved gastrointestinal tract epithelium activity and integrity, as reflected by epithelial cell growth in response to potential changes in bacterial-derived short-chain fatty acid production, crop epithelial morphology was compared between abalone fed the kelp-supplemented and control feeds. Kelp supplementation did not induce any observable changes in crop epithelial cell height for farm-reared sub-adult abalone fed the experimental diets on-farm for seven weeks. This was attributed to the similar macronutrient compositions of kelp-supplemented and control diets and/ or the common diet history of experimental abalone from weaning to the initiation of the experiment. Digestive enzyme activity was compared between abalone fed a kelp-supplemented and a control feed during an on-farm feeding trial with sub-adult abalone. Gut samples were collected after seven weeks and colorimetric enzyme assays were performed for the polysaccharide-degrading enzymes amylase, alginate lyase, laminarinase and fucoidanase, and for acid protease, trypsin and chymotrypsin activity. Amylase and alginate lyase activities were relatively high, compared to the other enzymes. Polysaccharidase and acid protease activity levels did not differ significantly between abalone fed kelp-supplemented and control feeds, but a greater variability in enzyme activity levels was observed in abalone fed the control diet. It was hypothesised that this might be due to the kelp supplement promoting a more stable and less opportunistic gut-bacterial community than the control diet. Pooled gut samples of abalone fed the kelp-supplemented diet were used for proteomic analyses to identify the composition of enzyme proteins of both endogenous and exogenous origin in the abalone digestive system. The key polysaccharidases and proteases in the gut samples of kelp-supplemented formulated feed-fed abalone were all of abalone origin, whereas the bacterial enzymes were of the types that form part of intermediate reactions in metabolic pathways. The results suggested that bacterial enzymes play a different role to abalone endogenous enzymes in the digestion of formulated feed. While abalone enzymes appear to be the main degraders of carbohydrate and protein macromolecules, the profile of exogenous enzymes suggests that they perform bioconversions of smaller organic compounds. The profiles of gut-bacterial communities of farm-reared sub-adult abalone fed kelpsupplemented and control feeds on-farm for seven weeks were analysed with metagenomic pyrosequencing and DGGE analyses, using 16S rDNA-targeted amplified DNA. The results indicated a shift in gut-bacterial composition with a higher abundance of Mollicutes in abalone fed kelp-supplemented feed compared to those fed the control feed. DGGE band patterns displayed a greater within-group similarity in gut bacteria for abalone fed the kelpsupplemented diet and the presence of unique and variable bands for bacteria in the guts of abalone fed the control diet. It was concluded that when cultured abalone are fed kelpsupplemented formulated feeds, more stable gut bacterial communities are present compared to a more opportunistic gut-bacterial community in abalone fed non-supplemented feeds, and that the observed increase in Mollicutes could reflect the restoration of the abalone gut microbiota to a more natural state. The novel application of proteomics to abalone nutrition in the present study demonstrated that gut-bacterial enzymes may form part of many different metabolic pathways and suggests that the metabolism of the gut microbiota serves as an extension of the abalone’s digestive metabolism. Future studies should quantify the contribution of commensal gut-bacteria to cultured abalone nutrition by employing metabolomic studies to characterize the utilisation of bacterial-derived metabolites by the abalone host.
- Full Text:
- Date Issued: 2016
- Authors: Nel, Aldi
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/899 , vital:20001
- Description: Formulated feeds with a relatively low (< 5 % of dry mass) kelp (Ecklonia maxima) inclusion level are widely used on commercial abalone (Haliotis midae) farms in South Africa. Although the use of kelp, a major constituent of the natural diet of H. midae, as a dietary supplement is considered to enhance abalone growth and feed utilisation, there are no published studies which quantify the effects of kelp inclusion in formulated feeds. Furthermore, the physiological mechanisms by which kelp supplementation may positively influence abalone digestive physiology and growth are largely unknown. As the kelp supplement is comprised mostly of soluble fibres and abalone gut bacteria associated with macroalgae (and its fibrous polysaccharides) are known to play a key role in digestion, it was hypothesised that the kelp supplement influences the gut-bacterial community profiles of cultured abalone through prebiotic and other metabolic effects. The present thesis thus examined the effect of kelp supplementation on the performance of abalone (Haliotis midae) fed formulated feeds and explored the influence of a kelp supplement on the abalone gut microbiota and its function in the gastrointestinal tract. The key hypotheses of the study were that kelp supplementation in formulated feed: 1) enhances abalone growth; 2) causes a shift in abalone gut-bacterial community composition through a prebiotic-like effect; 3) may induce changes in crop morphology as a result of potential bacterial-associated increases in volatile short-chain fatty acids, and 4) alters digestive enzyme activities in the abalone gut through changes in bacterial-derived (exogenous) digestive enzymes. The growth-promoting efficacy of low-level kelp supplementation was tested by feeding isonitrogenous and isoenergetic experimental feeds containing 0.00 – 3.54 % kelp (dry mass) to sub-adult abalone (~43 mm shell length) for eight months under commercial farm conditions. The growth trial established that kelp supplementation (0.44 – 3.54 % of dry mass) promoted faster growth and improved feed conversion and protein efficiency ratios in cultured abalone compared to abalone fed the non-supplemented control diet, while there were no significant differences in growth for abalone fed the different kelp-supplemented diets (0.44, 0.88, 1.76 and 3.54 % of dry mass). Feed conversion and protein efficiency ratios displayed significant correlations with kelp level in the range of 0.00 – 3.54 % dry mass, and it is therefore recommended that kelp be included in the formulated feeds of cultured South African abalone at a rate of up to 3.54 % of dry mass. A kelp-supplemented (0.88 % dry weight inclusion) feed was fed to abalone under farm conditions to compare gut physiological parameters (crop morphology, digestive enzyme activities and the gut microbiota) in abalone against that of abalone fed an isonitrogenous and isoenergetic non-supplemented control feed. To establish if the observed higher abalone growth rates were related to improved gastrointestinal tract epithelium activity and integrity, as reflected by epithelial cell growth in response to potential changes in bacterial-derived short-chain fatty acid production, crop epithelial morphology was compared between abalone fed the kelp-supplemented and control feeds. Kelp supplementation did not induce any observable changes in crop epithelial cell height for farm-reared sub-adult abalone fed the experimental diets on-farm for seven weeks. This was attributed to the similar macronutrient compositions of kelp-supplemented and control diets and/ or the common diet history of experimental abalone from weaning to the initiation of the experiment. Digestive enzyme activity was compared between abalone fed a kelp-supplemented and a control feed during an on-farm feeding trial with sub-adult abalone. Gut samples were collected after seven weeks and colorimetric enzyme assays were performed for the polysaccharide-degrading enzymes amylase, alginate lyase, laminarinase and fucoidanase, and for acid protease, trypsin and chymotrypsin activity. Amylase and alginate lyase activities were relatively high, compared to the other enzymes. Polysaccharidase and acid protease activity levels did not differ significantly between abalone fed kelp-supplemented and control feeds, but a greater variability in enzyme activity levels was observed in abalone fed the control diet. It was hypothesised that this might be due to the kelp supplement promoting a more stable and less opportunistic gut-bacterial community than the control diet. Pooled gut samples of abalone fed the kelp-supplemented diet were used for proteomic analyses to identify the composition of enzyme proteins of both endogenous and exogenous origin in the abalone digestive system. The key polysaccharidases and proteases in the gut samples of kelp-supplemented formulated feed-fed abalone were all of abalone origin, whereas the bacterial enzymes were of the types that form part of intermediate reactions in metabolic pathways. The results suggested that bacterial enzymes play a different role to abalone endogenous enzymes in the digestion of formulated feed. While abalone enzymes appear to be the main degraders of carbohydrate and protein macromolecules, the profile of exogenous enzymes suggests that they perform bioconversions of smaller organic compounds. The profiles of gut-bacterial communities of farm-reared sub-adult abalone fed kelpsupplemented and control feeds on-farm for seven weeks were analysed with metagenomic pyrosequencing and DGGE analyses, using 16S rDNA-targeted amplified DNA. The results indicated a shift in gut-bacterial composition with a higher abundance of Mollicutes in abalone fed kelp-supplemented feed compared to those fed the control feed. DGGE band patterns displayed a greater within-group similarity in gut bacteria for abalone fed the kelpsupplemented diet and the presence of unique and variable bands for bacteria in the guts of abalone fed the control diet. It was concluded that when cultured abalone are fed kelpsupplemented formulated feeds, more stable gut bacterial communities are present compared to a more opportunistic gut-bacterial community in abalone fed non-supplemented feeds, and that the observed increase in Mollicutes could reflect the restoration of the abalone gut microbiota to a more natural state. The novel application of proteomics to abalone nutrition in the present study demonstrated that gut-bacterial enzymes may form part of many different metabolic pathways and suggests that the metabolism of the gut microbiota serves as an extension of the abalone’s digestive metabolism. Future studies should quantify the contribution of commensal gut-bacteria to cultured abalone nutrition by employing metabolomic studies to characterize the utilisation of bacterial-derived metabolites by the abalone host.
- Full Text:
- Date Issued: 2016
The effect of novel thiazole-derived small molecules on the neuronal differentiation of human neuroblastoma SH-SY5Y cells
- Authors: Joos-Vandewalle, Julia
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64507 , vital:28554
- Description: Expected release date-April 2020
- Full Text:
- Date Issued: 2016
- Authors: Joos-Vandewalle, Julia
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64507 , vital:28554
- Description: Expected release date-April 2020
- Full Text:
- Date Issued: 2016
The effect of on-site wellness programs on absenteeism, presenteeism, stress and health care costs
- Authors: Gxolo, Zingisani Mzontsundu
- Date: 2016
- Subjects: Employee health promotion -- Economic aspects Absenteeism (Labor)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/14323 , vital:27570
- Description: The prevalence of health risk behaviours is growing among South African employees. The deteriorating health of the public and the costs there off, which arise from making unhealthy choices about one’s lifestyle, are a major cause of many preventable Non-Communicable Diseases (NCD’s). The effect of these NCD’s on an organisation can result in employees’ ill health and negative stress, which in turn can lead to absenteeism, presenteeism and thus decreased productivity. Several studies propose that the absenteeism together with presenteeism can cost an organisation up to three times as much as medical costs with stress also being flagged as a severe work-related hazard. Literature shows that ill health affects employee ability to function optimally, thus indirectly affects productivity. Studies on on-site wellness programs, although they report savings in health care costs and increase in productivity, their true effectiveness is not sufficiently measured. To add to this, there is a paucity of work that exists regarding the benefits of on-site wellness programs in South Africa. It is suggested that data about the effect of successful wellness programs does not always make its way to academic literature, thus the observed shortage in investment on such programs from South African companies. This study we aim to find out the effect of on-site wellness programs on absenteeism, presenteeism, stress and health care costs. The results oppose what literature findings report. Reasons for these findings are therefore speculated.
- Full Text:
- Date Issued: 2016
- Authors: Gxolo, Zingisani Mzontsundu
- Date: 2016
- Subjects: Employee health promotion -- Economic aspects Absenteeism (Labor)
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/14323 , vital:27570
- Description: The prevalence of health risk behaviours is growing among South African employees. The deteriorating health of the public and the costs there off, which arise from making unhealthy choices about one’s lifestyle, are a major cause of many preventable Non-Communicable Diseases (NCD’s). The effect of these NCD’s on an organisation can result in employees’ ill health and negative stress, which in turn can lead to absenteeism, presenteeism and thus decreased productivity. Several studies propose that the absenteeism together with presenteeism can cost an organisation up to three times as much as medical costs with stress also being flagged as a severe work-related hazard. Literature shows that ill health affects employee ability to function optimally, thus indirectly affects productivity. Studies on on-site wellness programs, although they report savings in health care costs and increase in productivity, their true effectiveness is not sufficiently measured. To add to this, there is a paucity of work that exists regarding the benefits of on-site wellness programs in South Africa. It is suggested that data about the effect of successful wellness programs does not always make its way to academic literature, thus the observed shortage in investment on such programs from South African companies. This study we aim to find out the effect of on-site wellness programs on absenteeism, presenteeism, stress and health care costs. The results oppose what literature findings report. Reasons for these findings are therefore speculated.
- Full Text:
- Date Issued: 2016
The effect of shaped nanoparticles on the photophysicochemical behaviour of metallophthalocyanines
- Authors: D'Souza, Sarah
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/529 , vital:19967
- Description: The synthesis, spectroscopic characterization and photophysicochemical analysis of novel and known metallophthalocyanines are reported in this thesis. The novel lowsymmetry compounds were extensively studied. Selected phthalocyanines were conjugated to a variety of nanoparticles consisting of silver (AgNPs), gold (AuNPs) and zinc oxide (ZnO NPs) in order to improve their photophysical and photochemical behaviour. As with the phthalocyanines, the nanoparticles and phthalocyaninenanoparticle conjugates were thoroughly investigated. Research on the effect of the solvent used, as well as the influence of nanoparticle composition and shape on the properties of the phthalocyanines, were performed. The findings showed that there was a general increase in triplet quantum yields of the phthalocyanines in the presence of the nanoparticles. It was also noted that the use of different solvents directly affected the photophysicochemical properties. In the case of the nanoparticle conjugates, photophysical and photochemical changes were observed. Of significance were the gold nanostars, which decreased the degree of phthalocyanine aggregation in water, resulting in increased fluorescence lifetimes. The studies also revealed that the effect of the nanoparticle shape on the phthalocyanine properties was highly dependent on the nanoparticle material. The photodynamic antimicrobial activity of selected phthalocyanine-zinc oxide nanoparticle conjugates was investigated against Staphylococcus aureus (S. aureus) in solution. The phthalocyanines alone exhibited remarkable growth inhibition, however the presence of the nanoparticles in the conjugates increased the photoinactivation of S. aureus.
- Full Text:
- Date Issued: 2016
- Authors: D'Souza, Sarah
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/529 , vital:19967
- Description: The synthesis, spectroscopic characterization and photophysicochemical analysis of novel and known metallophthalocyanines are reported in this thesis. The novel lowsymmetry compounds were extensively studied. Selected phthalocyanines were conjugated to a variety of nanoparticles consisting of silver (AgNPs), gold (AuNPs) and zinc oxide (ZnO NPs) in order to improve their photophysical and photochemical behaviour. As with the phthalocyanines, the nanoparticles and phthalocyaninenanoparticle conjugates were thoroughly investigated. Research on the effect of the solvent used, as well as the influence of nanoparticle composition and shape on the properties of the phthalocyanines, were performed. The findings showed that there was a general increase in triplet quantum yields of the phthalocyanines in the presence of the nanoparticles. It was also noted that the use of different solvents directly affected the photophysicochemical properties. In the case of the nanoparticle conjugates, photophysical and photochemical changes were observed. Of significance were the gold nanostars, which decreased the degree of phthalocyanine aggregation in water, resulting in increased fluorescence lifetimes. The studies also revealed that the effect of the nanoparticle shape on the phthalocyanine properties was highly dependent on the nanoparticle material. The photodynamic antimicrobial activity of selected phthalocyanine-zinc oxide nanoparticle conjugates was investigated against Staphylococcus aureus (S. aureus) in solution. The phthalocyanines alone exhibited remarkable growth inhibition, however the presence of the nanoparticles in the conjugates increased the photoinactivation of S. aureus.
- Full Text:
- Date Issued: 2016
The effect of silica on the reduction of precipitated iron-based fischer-tropsch catalysts
- Authors: Coombes, Matthew
- Date: 2016
- Subjects: Fischer-Tropsch process Reduction (Chemistry) , Catalysts
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/14873 , vital:27888
- Description: Iron Fischer-Tropsch (FT) catalysts are typically prepared as iron oxides which are reduced to FT-active iron metal and iron carbide prior to FT synthesis. The iron oxides contain a variety of different chemical and structural promoters to alter FT-activity. Silica is a common structural promoter which stabilises the formation of small crystallites and provides mechanical integrity to the catalyst. However, silica inhibits the reduction of the oxide precursor to the FT-active phases. This ultimately affects catalyst activity and product selectivity. It has been proposed that the silica interacts with the iron to form encapsulating shells of fayalite (Fe2SiO4), or fayalite rafts between the iron oxide and the silica support. In this study, six silica-promoted iron oxide samples were prepared using a simple co-precipitation technique. Samples contain varying amounts of silica, and the samples are named 100/x Fe/SiO2, where x is the weight of silica for 100 weight iron, with x taking on values of 0, 10, 25, 50, 100 and 200. The resulting iron oxides were characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), M¨ossbauer spectroscopy (MS), magnetic susceptibility measurements (MM), Raman spectroscopy, thermal gravimetric analysis (TGA) and nitrogen physisorption. Their reduction in a hydrogen atmosphere was investigated using temperature programmed reduction (TPR), in situ XRPD and TEM. The reduction in hydrogen of 100/0 Fe/SiO2 and 100/10 Fe/SiO2 was also studied using in situ gas flow TEM cells. These cells allow the samples to be studied in the electron microscope at temperature and pressure conditions approaching those experienced in a real reactor environment. In the absence of a silica promoter (100/0 Fe/SiO2), hematite particles are formed with mean particle diameters of 39 ± 12 and 52.7 ± 0.2 nm determined using TEM and XRPD respectively. MM data reveals a magnetic transition (Morin transition) at≈230 K, consistent with a mean particle size of≈50 nm. In a hydrogen atmosphere, the hematite reduces to metallic iron via a two-step process viz. hematite → magnetite → iron. The final iron particles have an average crystallite size of 68.0 ± 0.2 nm. The presence of lower amounts of silica in the samples 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 results in the formation of silicasubstituted 2-line ferrihydrite particles. Bands in the Raman spectra of these samples shift on increasing silica content, which indicates an increasing number of Fe-O-Si bonds within the ferrihydrite framework. MM reveals typical superparamagnetic (SPM) behaviour above a blocking temperature in the range 39 - 68 K which gives mean particle sizes of 4.2, 3.6 and 3.5 nm for 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 respectively, in good agreement with particle sizes determined using TEM (3.1±0.4, 2.4±0.3 and 2.4±0.3 nm respectively). MS data at 300 K and 4.2 K were fitted with distributions of ∆EQ and Bhf respectively. The median values of Bhf decrease with increasing silica content, indicating greater degrees of distortion in the Fe3+ environments induced by increased silica substitution. The reduction to metallic iron occurs via a three-step process viz. hematite → magnetite → wu¨stite → iron, with the silica stabilising the wu¨stite phase. The increasing amount of Fe-O-Si bonds on increasing silica content shifts reduction to higher temperatures broadens each reduction step as a result of local Fe-O-Si concentration variations. Fractions of each sample are not completely reduced even at 1000°C, with the relative proportion increasing with increasing silica content. In situ gas flow TEM studies reveal that the mechanism of reduction involves the liberation of atomic iron atoms from the silica-substituted iron oxides which agglomerate and grow into final iron particles. This leaves a poorly crystalline Fe-O-Si bonded framework behind. STEM-EDS and STEM-EELS reveal low concentrations of silicon at the surface of the resulting iron particles, however they do not form encapsulating shells of fayalite as previously suggested. The majority of the silica remains in the Fe-O-Si material which may crystallise into separate fayalite particles at elevated temperature. The presence of silica in high proportions (100/100 Fe/SiO2 and 100/200 Fe/SiO2) results in the formation of a two-phase system consisting of silicasubstituted 2-line ferrihydrite particles which are encapsulated in an ironinfused amorphous silica network. As with the other silica-bearing samples, there is an increase in Fe-O-Si bonds and an increase in the degree of distortion at Fe3+ sites with increasing silica content. The large amount of silica suppresses the blocking temperature of the SPM crystallites. In a hydrogen atmosphere, the reduction to metallic iron follows the same three step process as the other silica-bearing samples. Reduction temperatures are further shifted to higher values and given reduction steps are considerably broader with increasing silica content. The fraction of iron not fully reduced also increases. Iron particle diameters are very small, since encapsulation by the silica matrix prevents growth of particles.
- Full Text:
- Date Issued: 2016
- Authors: Coombes, Matthew
- Date: 2016
- Subjects: Fischer-Tropsch process Reduction (Chemistry) , Catalysts
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/14873 , vital:27888
- Description: Iron Fischer-Tropsch (FT) catalysts are typically prepared as iron oxides which are reduced to FT-active iron metal and iron carbide prior to FT synthesis. The iron oxides contain a variety of different chemical and structural promoters to alter FT-activity. Silica is a common structural promoter which stabilises the formation of small crystallites and provides mechanical integrity to the catalyst. However, silica inhibits the reduction of the oxide precursor to the FT-active phases. This ultimately affects catalyst activity and product selectivity. It has been proposed that the silica interacts with the iron to form encapsulating shells of fayalite (Fe2SiO4), or fayalite rafts between the iron oxide and the silica support. In this study, six silica-promoted iron oxide samples were prepared using a simple co-precipitation technique. Samples contain varying amounts of silica, and the samples are named 100/x Fe/SiO2, where x is the weight of silica for 100 weight iron, with x taking on values of 0, 10, 25, 50, 100 and 200. The resulting iron oxides were characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRPD), M¨ossbauer spectroscopy (MS), magnetic susceptibility measurements (MM), Raman spectroscopy, thermal gravimetric analysis (TGA) and nitrogen physisorption. Their reduction in a hydrogen atmosphere was investigated using temperature programmed reduction (TPR), in situ XRPD and TEM. The reduction in hydrogen of 100/0 Fe/SiO2 and 100/10 Fe/SiO2 was also studied using in situ gas flow TEM cells. These cells allow the samples to be studied in the electron microscope at temperature and pressure conditions approaching those experienced in a real reactor environment. In the absence of a silica promoter (100/0 Fe/SiO2), hematite particles are formed with mean particle diameters of 39 ± 12 and 52.7 ± 0.2 nm determined using TEM and XRPD respectively. MM data reveals a magnetic transition (Morin transition) at≈230 K, consistent with a mean particle size of≈50 nm. In a hydrogen atmosphere, the hematite reduces to metallic iron via a two-step process viz. hematite → magnetite → iron. The final iron particles have an average crystallite size of 68.0 ± 0.2 nm. The presence of lower amounts of silica in the samples 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 results in the formation of silicasubstituted 2-line ferrihydrite particles. Bands in the Raman spectra of these samples shift on increasing silica content, which indicates an increasing number of Fe-O-Si bonds within the ferrihydrite framework. MM reveals typical superparamagnetic (SPM) behaviour above a blocking temperature in the range 39 - 68 K which gives mean particle sizes of 4.2, 3.6 and 3.5 nm for 100/10 Fe/SiO2, 100/25 Fe/SiO2 and 100/50 Fe/SiO2 respectively, in good agreement with particle sizes determined using TEM (3.1±0.4, 2.4±0.3 and 2.4±0.3 nm respectively). MS data at 300 K and 4.2 K were fitted with distributions of ∆EQ and Bhf respectively. The median values of Bhf decrease with increasing silica content, indicating greater degrees of distortion in the Fe3+ environments induced by increased silica substitution. The reduction to metallic iron occurs via a three-step process viz. hematite → magnetite → wu¨stite → iron, with the silica stabilising the wu¨stite phase. The increasing amount of Fe-O-Si bonds on increasing silica content shifts reduction to higher temperatures broadens each reduction step as a result of local Fe-O-Si concentration variations. Fractions of each sample are not completely reduced even at 1000°C, with the relative proportion increasing with increasing silica content. In situ gas flow TEM studies reveal that the mechanism of reduction involves the liberation of atomic iron atoms from the silica-substituted iron oxides which agglomerate and grow into final iron particles. This leaves a poorly crystalline Fe-O-Si bonded framework behind. STEM-EDS and STEM-EELS reveal low concentrations of silicon at the surface of the resulting iron particles, however they do not form encapsulating shells of fayalite as previously suggested. The majority of the silica remains in the Fe-O-Si material which may crystallise into separate fayalite particles at elevated temperature. The presence of silica in high proportions (100/100 Fe/SiO2 and 100/200 Fe/SiO2) results in the formation of a two-phase system consisting of silicasubstituted 2-line ferrihydrite particles which are encapsulated in an ironinfused amorphous silica network. As with the other silica-bearing samples, there is an increase in Fe-O-Si bonds and an increase in the degree of distortion at Fe3+ sites with increasing silica content. The large amount of silica suppresses the blocking temperature of the SPM crystallites. In a hydrogen atmosphere, the reduction to metallic iron follows the same three step process as the other silica-bearing samples. Reduction temperatures are further shifted to higher values and given reduction steps are considerably broader with increasing silica content. The fraction of iron not fully reduced also increases. Iron particle diameters are very small, since encapsulation by the silica matrix prevents growth of particles.
- Full Text:
- Date Issued: 2016
The effective management of customer orders received by a pharmaceutical manufacturer
- Authors: Botha, Risca
- Date: 2016
- Subjects: Pharmaceutical industry -- Customer services , Business logistics , Physical distribution of goods -- Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/9087 , vital:26463
- Description: There is a great need for a pharmaceutical manufacturer to provide its customers with the right product at the right time, place and price and also to deliver the product in the right quantity and quality. Should pharmaceutical customers not receive their orders on time from the pharmaceutical manufacturer, the customers might face out-of-stock situations. As a result, the patients or customers might turn to an alternative product from a different pharmaceutical manufacturer, which has the required stock readily available. This could lead to loss in sales and even death amongst its customers. The main objective of this study was to determine the key factors that form part of the demand and operations planning strategies to ensure that these factors are in place to effectively manage and execute the supply chain and logistics processes to reduce possible out-of-stock situations amongst its customers. As a starting point to the study, an analysis was performed based on the review of relevant research and literature from various text books, journals, publications, as well as internet sources. The literature study covered various aspects such as demand planning, production planning, the use of different demand and operations planning strategies, as well as the importance of continuous internal and external customer service levels to ensure that customer orders are delivered on time. The analysis of the literature review was used to establish a theoretical basis for the design and structure of the questionnaire that was used as a research instrument in this study. A survey was conducted amongst the employees that are responsible for executing the supply chain and logistics processes within Aspen Pharmacare. These employees resided within the three main departments of the pharmaceutical manufacturer, namely, the Demand and Operations Planning, Production and Packing, as well as the Warehouse and Distribution departments. Each question posed in the questionnaire related to the role of each employee within these departments that are responsible for the logistics processes within Aspen Pharmacare. The empirical results from the study indicated that the respondents were in support that specific key factors are important for a pharmaceutical manufacturer to manage incoming customer orders efficiently and effectively to reduce possible out-of-stock situations amongst its end customers. However, the respondents also highlighted that there were a number of obstacles preventing them from implementing the key factors that are required to manage incoming customer orders more efficiently within the pharmaceutical manufacturer. Some of these obstacles include: the lack of pro- activeness; lack of accountability; and the lack of constant communication between the employees from the three main departments. Furthermore, incomplete hand-over information during shift changes amongst the employees of the Production and Packing department created unnecessary down-time. Also, the employees from the Warehouse and Distribution department were not informed timeously when changes to the production schedule were made. These obstacles will have a negative impact on the ultimate customer delivery dates and need to be addressed. The empirical results highlighted some recommendations to assist pharmaceutical manufacturing companies to more effectively and efficiently manage their incoming customer orders to reduce or eliminate any possible out-of-stock situations amongst its end customers. Some recommendations include: improved communication between the three main departments; to react immediately to out-of-stock products; and to ensure that internal and external customer service levels are adhered to at all times. The implementation of the recommendations based on the empirical findings of the study will assist the pharmaceutical manufacturing company to achieve excellence and to become a world-class supplier of generic pharmaceutical products. In this way, all incoming customer orders can be fulfilled on time.
- Full Text:
- Date Issued: 2016
- Authors: Botha, Risca
- Date: 2016
- Subjects: Pharmaceutical industry -- Customer services , Business logistics , Physical distribution of goods -- Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/9087 , vital:26463
- Description: There is a great need for a pharmaceutical manufacturer to provide its customers with the right product at the right time, place and price and also to deliver the product in the right quantity and quality. Should pharmaceutical customers not receive their orders on time from the pharmaceutical manufacturer, the customers might face out-of-stock situations. As a result, the patients or customers might turn to an alternative product from a different pharmaceutical manufacturer, which has the required stock readily available. This could lead to loss in sales and even death amongst its customers. The main objective of this study was to determine the key factors that form part of the demand and operations planning strategies to ensure that these factors are in place to effectively manage and execute the supply chain and logistics processes to reduce possible out-of-stock situations amongst its customers. As a starting point to the study, an analysis was performed based on the review of relevant research and literature from various text books, journals, publications, as well as internet sources. The literature study covered various aspects such as demand planning, production planning, the use of different demand and operations planning strategies, as well as the importance of continuous internal and external customer service levels to ensure that customer orders are delivered on time. The analysis of the literature review was used to establish a theoretical basis for the design and structure of the questionnaire that was used as a research instrument in this study. A survey was conducted amongst the employees that are responsible for executing the supply chain and logistics processes within Aspen Pharmacare. These employees resided within the three main departments of the pharmaceutical manufacturer, namely, the Demand and Operations Planning, Production and Packing, as well as the Warehouse and Distribution departments. Each question posed in the questionnaire related to the role of each employee within these departments that are responsible for the logistics processes within Aspen Pharmacare. The empirical results from the study indicated that the respondents were in support that specific key factors are important for a pharmaceutical manufacturer to manage incoming customer orders efficiently and effectively to reduce possible out-of-stock situations amongst its end customers. However, the respondents also highlighted that there were a number of obstacles preventing them from implementing the key factors that are required to manage incoming customer orders more efficiently within the pharmaceutical manufacturer. Some of these obstacles include: the lack of pro- activeness; lack of accountability; and the lack of constant communication between the employees from the three main departments. Furthermore, incomplete hand-over information during shift changes amongst the employees of the Production and Packing department created unnecessary down-time. Also, the employees from the Warehouse and Distribution department were not informed timeously when changes to the production schedule were made. These obstacles will have a negative impact on the ultimate customer delivery dates and need to be addressed. The empirical results highlighted some recommendations to assist pharmaceutical manufacturing companies to more effectively and efficiently manage their incoming customer orders to reduce or eliminate any possible out-of-stock situations amongst its end customers. Some recommendations include: improved communication between the three main departments; to react immediately to out-of-stock products; and to ensure that internal and external customer service levels are adhered to at all times. The implementation of the recommendations based on the empirical findings of the study will assist the pharmaceutical manufacturing company to achieve excellence and to become a world-class supplier of generic pharmaceutical products. In this way, all incoming customer orders can be fulfilled on time.
- Full Text:
- Date Issued: 2016
The effectiveness of brain-compatible blended learning material in the teaching of programming logic
- Van Niekerk, Johannes Frederick, Webb, Paul
- Authors: Van Niekerk, Johannes Frederick , Webb, Paul
- Date: 2016
- Subjects: Blended learning -- South Africa , Learning, Psychology of , Computer-assisted instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/45344 , vital:38572
- Description: Blended learning is an educational approach which integrates seemingly distinct educational approaches such as face-to-face and online experiences. In a blended learning environment, the classroom lectures can, for example, be augmented with learning material opened in a variety of technologically delivered formats. Brain-compatible learning is an approach to education which stems from a combination of neuroscience and educational psychology. Brain compatible learning is not a formalised education approach or recipe for teachers', instead it provides a `set of principles and a base of knowledge and skills upon which we can make better decisions about the learning process. While the electiveness of education based on brain-compatible learning principles have been proven in a classroom environment, very little knowledge exists regarding its use in an e-learning environment. The purpose of this research was to determine whether an e-learning intervention which was designed according to brain-compatible learning principles would have an elect on student motivation to learn and on student achievement in the subject Technical programming 1. An e-learning based educational intervention which incorporated several brain-compatible learning principles was designed and administered as a controlled experiment intervention. The impact of the research experiment was measured both qualitatively using an purpose-designed instrument and quantitatively through an analysis of the formal assessments for this subject. The findings of this study, namely that brain-compatible learning principles can be used in an e-learning environment and that e-learning material which adheres to brain-compatible education principles have a positive elect on Technical Programming 1 students' achievement and motivation to learn, appear to be meaningful contributions to the current debate on blended learning.
- Full Text:
- Date Issued: 2016
The effectiveness of brain-compatible blended learning material in the teaching of programming logic
- Authors: Van Niekerk, Johannes Frederick , Webb, Paul
- Date: 2016
- Subjects: Blended learning -- South Africa , Learning, Psychology of , Computer-assisted instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10948/45344 , vital:38572
- Description: Blended learning is an educational approach which integrates seemingly distinct educational approaches such as face-to-face and online experiences. In a blended learning environment, the classroom lectures can, for example, be augmented with learning material opened in a variety of technologically delivered formats. Brain-compatible learning is an approach to education which stems from a combination of neuroscience and educational psychology. Brain compatible learning is not a formalised education approach or recipe for teachers', instead it provides a `set of principles and a base of knowledge and skills upon which we can make better decisions about the learning process. While the electiveness of education based on brain-compatible learning principles have been proven in a classroom environment, very little knowledge exists regarding its use in an e-learning environment. The purpose of this research was to determine whether an e-learning intervention which was designed according to brain-compatible learning principles would have an elect on student motivation to learn and on student achievement in the subject Technical programming 1. An e-learning based educational intervention which incorporated several brain-compatible learning principles was designed and administered as a controlled experiment intervention. The impact of the research experiment was measured both qualitatively using an purpose-designed instrument and quantitatively through an analysis of the formal assessments for this subject. The findings of this study, namely that brain-compatible learning principles can be used in an e-learning environment and that e-learning material which adheres to brain-compatible education principles have a positive elect on Technical Programming 1 students' achievement and motivation to learn, appear to be meaningful contributions to the current debate on blended learning.
- Full Text:
- Date Issued: 2016
The effectiveness of internal financial controls with specific reference to the Eastern Cape Provincial Department of Basic Education
- Authors: Tini, Sabelo
- Date: 2016
- Subjects: Education -- Finance School management and organization -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/1896 , vital:27577
- Description: The purpose of this study was to assess the effectiveness of internal financial controls with specific reference to the Eastern Cape provincial department of basic education. A self-administered questionnaire was used to collect data. The questionnaire was filled by the respondents who are directly involved in processing payments and procuring for the departments. The findings have shown that Internal control system does exists within the department however the implementation and monitoring of its effectiveness needs to be strengthened. The findings show that the internal control system have an important role to play in attaining desired positive results within the department. Internal control effectiveness is one of the most important aspects in any organisation, whether in a private sector or in the public sector. It determines the stewardship of an entity’s management. The PFMA states that the accounting officer of a department must ensure that that department has and maintains effective, efficient and transparent systems of financial and risk management and internal control. If public officials could strictly adhere to the stipulated internal controls, there will be a positive response to accountability and also in service delivery as expected by the citizens. Public accountability gives a reflection on how does the entity conducts its business affairs in terms of adhering to the norms and standards as prescribed by the law and whether there are any strong controls to prevent acts of fraud and corruption.
- Full Text:
- Date Issued: 2016
- Authors: Tini, Sabelo
- Date: 2016
- Subjects: Education -- Finance School management and organization -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/1896 , vital:27577
- Description: The purpose of this study was to assess the effectiveness of internal financial controls with specific reference to the Eastern Cape provincial department of basic education. A self-administered questionnaire was used to collect data. The questionnaire was filled by the respondents who are directly involved in processing payments and procuring for the departments. The findings have shown that Internal control system does exists within the department however the implementation and monitoring of its effectiveness needs to be strengthened. The findings show that the internal control system have an important role to play in attaining desired positive results within the department. Internal control effectiveness is one of the most important aspects in any organisation, whether in a private sector or in the public sector. It determines the stewardship of an entity’s management. The PFMA states that the accounting officer of a department must ensure that that department has and maintains effective, efficient and transparent systems of financial and risk management and internal control. If public officials could strictly adhere to the stipulated internal controls, there will be a positive response to accountability and also in service delivery as expected by the citizens. Public accountability gives a reflection on how does the entity conducts its business affairs in terms of adhering to the norms and standards as prescribed by the law and whether there are any strong controls to prevent acts of fraud and corruption.
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- Date Issued: 2016