Trends in the TD-DFT calculations of porphyrin and phthalocyanine analogs
- Mack, John, Stone, Justin, Nyokong, Tebello
- Authors: Mack, John , Stone, Justin , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193882 , vital:45402 , xlink:href="https://doi.org/10.1142/S108842461450045X"
- Description: In 2005, Kobayashi and coworkers reported trends in the TD-DFT spectra of 17 Zn (II) porphyrinoids [J. Am. Chem. Soc. 2005; 127: 17697] that were analyzed using Michl's perimeter model as part of a study of the anomalous magnetic circular dichroism (MCD) spectroscopy of zinc tetraphenyltetraacenaphthoporphyrin. In recent years, it has become increasingly clear that TD-DFT calculations with the commonly used hybrid B3LYP exchange-correlation functional of the Gaussian software package are problematic in the B-band region of porphyrinoid spectra, since the degree of configurational interaction between the B and higher energy ππ* state appears to be significantly overestimated. The CAM-B3LYP functional is now often preferred for analyzing the optical properties of porphyrinoids, since it includes a long-range correction of the exchange potential, which incorporates an increasing fraction of Hartree–Fock (HF) exchange as the interelectronic separation increases, making it better suited for studying compounds where there is significant charge transfer in the electronic excited states. The trends in the TD-DFT calculations are reexamined with a wider range porphyrinoid compounds including several with pyrazino moieties and are found to provide a closer agreement with the experimental in the B-band region for complexes such as zinc tetraphenylporphyrin and phthalocyanine.
- Full Text:
- Date Issued: 2014
- Authors: Mack, John , Stone, Justin , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193882 , vital:45402 , xlink:href="https://doi.org/10.1142/S108842461450045X"
- Description: In 2005, Kobayashi and coworkers reported trends in the TD-DFT spectra of 17 Zn (II) porphyrinoids [J. Am. Chem. Soc. 2005; 127: 17697] that were analyzed using Michl's perimeter model as part of a study of the anomalous magnetic circular dichroism (MCD) spectroscopy of zinc tetraphenyltetraacenaphthoporphyrin. In recent years, it has become increasingly clear that TD-DFT calculations with the commonly used hybrid B3LYP exchange-correlation functional of the Gaussian software package are problematic in the B-band region of porphyrinoid spectra, since the degree of configurational interaction between the B and higher energy ππ* state appears to be significantly overestimated. The CAM-B3LYP functional is now often preferred for analyzing the optical properties of porphyrinoids, since it includes a long-range correction of the exchange potential, which incorporates an increasing fraction of Hartree–Fock (HF) exchange as the interelectronic separation increases, making it better suited for studying compounds where there is significant charge transfer in the electronic excited states. The trends in the TD-DFT calculations are reexamined with a wider range porphyrinoid compounds including several with pyrazino moieties and are found to provide a closer agreement with the experimental in the B-band region for complexes such as zinc tetraphenylporphyrin and phthalocyanine.
- Full Text:
- Date Issued: 2014
Triggering physics lecturers' reflections on the instructional affordance of their use of representations: a design-based study
- Authors: Lombard, Elsa Helena
- Date: 2014
- Subjects: Physics -- Study and teaching , Physics -- Research
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2899 , vital:20361
- Description: There is growing awareness in the physics education research community about the importance of using representations in physics teaching and the need for lecturers to reflect on their practice. This research study adopted a design-based research approach in an attempt to design a reliable, valid and practically useful artefact (framework/strategy) that could be used to trigger introductory physics lecturers’ reflections on their instructional use of representations. The artefact, which was instantiated with physics lecturers, comprised an observation protocol, an accompanying definitions key, a communication platform, and an instrument to assess the outcome (the levels of reflection). The video-data of lecturer practice were analysed using a priori codes to generate profiles of teaching practice. The resulting profiles were used to trigger individual video-stimulated reflection. The levels of reflection were assessed using a purpose-designed ‘Expectations of Reflection’ taxonomy. Thereafter a set of design guidelines and design principles were generated to guide further similar design-based educational studies. The process was validated via interview data but, while it was deemed a valid and reliable solution to the research problem, there were varying levels of perceived value of the artefact among the participating lecturers.
- Full Text:
- Date Issued: 2014
- Authors: Lombard, Elsa Helena
- Date: 2014
- Subjects: Physics -- Study and teaching , Physics -- Research
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/2899 , vital:20361
- Description: There is growing awareness in the physics education research community about the importance of using representations in physics teaching and the need for lecturers to reflect on their practice. This research study adopted a design-based research approach in an attempt to design a reliable, valid and practically useful artefact (framework/strategy) that could be used to trigger introductory physics lecturers’ reflections on their instructional use of representations. The artefact, which was instantiated with physics lecturers, comprised an observation protocol, an accompanying definitions key, a communication platform, and an instrument to assess the outcome (the levels of reflection). The video-data of lecturer practice were analysed using a priori codes to generate profiles of teaching practice. The resulting profiles were used to trigger individual video-stimulated reflection. The levels of reflection were assessed using a purpose-designed ‘Expectations of Reflection’ taxonomy. Thereafter a set of design guidelines and design principles were generated to guide further similar design-based educational studies. The process was validated via interview data but, while it was deemed a valid and reliable solution to the research problem, there were varying levels of perceived value of the artefact among the participating lecturers.
- Full Text:
- Date Issued: 2014
Trophic relationships of hake (Merluccius capensis Castelnau, 1851 and M. paradoxus Franca 1960) from the Northern Benguela current ecosystem (Namibia) : inferences from stable isotopes and fatty acids
- Authors: Iitembu, Johannes Angala
- Date: 2014
- Subjects: Hake -- Benguela Current , Merlucciidae -- Benguela Current , Multitrophic interactions (Ecology) , Food chains (Ecology) , Biotic communities -- Benguela Current , Merlucciidae -- Food , Fishery management -- Namibia , Stable isotopes , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5944 , http://hdl.handle.net/10962/d1020296
- Description: Two species of hake (Merluccius capensis and Merluccius paradoxus) account for most of Namibia’s fisheries catch, and they are important secondary consumers in the Benguela Current ecosystem. Inferences on their trophic relationships have been based mainly on stomach content analyses. However, such data are limited temporally because they represent only snapshots of recent feeding, and are quantitatively biased because of variation in the digestion rates of different prey. The principal aim of the thesis was to understand the trophic relationships of two hake species relative to each other, their known prey and top predators (demersal sharks) in the northern Benguela Current ecosystem (Namibia), using time-integrating trophic biomarkers. By using stable isotope (carbon and nitrogen) and fatty acid signatures of their muscle tissues, my overall objectives were to produce new knowledge about 1) hake ontogenic trophic relationships, 2) the contributions of different prey to hake diets, 3) hake dietary differences, and 4) some aspects of hake’s trophic relationships with demersal sharks. Tissues of hake (n=358), their potential prey (n=455), and demersal sharks (n=42) were collected between 2008 and 2012 during demersal bottom trawl surveys off Namibia, for stable isotope and fatty acid analyses. And more...
- Full Text:
- Date Issued: 2014
- Authors: Iitembu, Johannes Angala
- Date: 2014
- Subjects: Hake -- Benguela Current , Merlucciidae -- Benguela Current , Multitrophic interactions (Ecology) , Food chains (Ecology) , Biotic communities -- Benguela Current , Merlucciidae -- Food , Fishery management -- Namibia , Stable isotopes , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5944 , http://hdl.handle.net/10962/d1020296
- Description: Two species of hake (Merluccius capensis and Merluccius paradoxus) account for most of Namibia’s fisheries catch, and they are important secondary consumers in the Benguela Current ecosystem. Inferences on their trophic relationships have been based mainly on stomach content analyses. However, such data are limited temporally because they represent only snapshots of recent feeding, and are quantitatively biased because of variation in the digestion rates of different prey. The principal aim of the thesis was to understand the trophic relationships of two hake species relative to each other, their known prey and top predators (demersal sharks) in the northern Benguela Current ecosystem (Namibia), using time-integrating trophic biomarkers. By using stable isotope (carbon and nitrogen) and fatty acid signatures of their muscle tissues, my overall objectives were to produce new knowledge about 1) hake ontogenic trophic relationships, 2) the contributions of different prey to hake diets, 3) hake dietary differences, and 4) some aspects of hake’s trophic relationships with demersal sharks. Tissues of hake (n=358), their potential prey (n=455), and demersal sharks (n=42) were collected between 2008 and 2012 during demersal bottom trawl surveys off Namibia, for stable isotope and fatty acid analyses. And more...
- Full Text:
- Date Issued: 2014
Troubling White Englishness in South Africa: a self-interrogation of privilege, complicity citizenship, and belonging
- Authors: Garman, Anthea
- Date: 2014
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/159746 , vital:40339 , ISBN 978-0739192962
- Description: Unveiling Whiteness in the Twenty-First Century: Global Manifestations, Transdisciplinary Interventions is a tightly interconnected and richly collaborative book that will advance our understanding of why it is so difficult to re-form and reimagine whiteness in the twenty-first century. Composed after the election of the first black U.S. president, post-global financial crisis, more than a decade after 9/11, and concomitant with a rash of xenophobic incidents across the globe, the book distills several key themes associated with a post-millennial global whiteness: the individual and collective emotions of whiteness, the recentering of whiteness through governing and legal strategies, and the retreats from social equity and justice that have characterized the late twentieth and twenty-first century nation state. It also attempts the difficult work of reimagining white identities and cultures for a new era.
- Full Text:
- Date Issued: 2014
- Authors: Garman, Anthea
- Date: 2014
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/159746 , vital:40339 , ISBN 978-0739192962
- Description: Unveiling Whiteness in the Twenty-First Century: Global Manifestations, Transdisciplinary Interventions is a tightly interconnected and richly collaborative book that will advance our understanding of why it is so difficult to re-form and reimagine whiteness in the twenty-first century. Composed after the election of the first black U.S. president, post-global financial crisis, more than a decade after 9/11, and concomitant with a rash of xenophobic incidents across the globe, the book distills several key themes associated with a post-millennial global whiteness: the individual and collective emotions of whiteness, the recentering of whiteness through governing and legal strategies, and the retreats from social equity and justice that have characterized the late twentieth and twenty-first century nation state. It also attempts the difficult work of reimagining white identities and cultures for a new era.
- Full Text:
- Date Issued: 2014
Tufa stromatolite ecosystems on the South African south coast
- Perissonotto, Renzo, Bornman, Tommy G, Steyn, Paul-Pierre, Miranda, Nelson A F, Dorrington, Rosemary A, Matcher, Gwynneth F, Strydom, Nadine A, Peer, Nasreen
- Authors: Perissonotto, Renzo , Bornman, Tommy G , Steyn, Paul-Pierre , Miranda, Nelson A F , Dorrington, Rosemary A , Matcher, Gwynneth F , Strydom, Nadine A , Peer, Nasreen
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:6490 , http://hdl.handle.net/10962/d1014585 , http://dx.doi.org/10.1590/sajs.2014/20140011
- Description: Following the first description of living marine stromatolites along the South African east coast, new investigations along the south coast have revealed the occurrence of extensive fields of actively calcifying stromatolites. These stromatolites have been recorded at regular distances along a 200-km stretch of coastline, from Cape Recife in the east to the Storms River mouth in the west, with the highest density found between Schoenmakerskop and the Maitland River mouth. All active stromatolites are associated with freshwater seepage streams flowing from the dune cordon, which form rimstone dams and other accretions capable of retaining water in the supratidal platform. Resulting pools can reach a maximum depth of about 1 m and constitute a unique ecosystem in which freshwater and marine organisms alternate their dominance in response to vertical mixing and the balance between freshwater versus marine inflow. Although the factors controlling stromatolite growth are yet to be determined, nitrogen appears to be supplied mainly via the dune seeps. The epibenthic algal community within stromatolite pools is generally co-dominated by cyanobacteria and chlorophytes, with minimal diatom contribution.
- Full Text:
- Date Issued: 2014
- Authors: Perissonotto, Renzo , Bornman, Tommy G , Steyn, Paul-Pierre , Miranda, Nelson A F , Dorrington, Rosemary A , Matcher, Gwynneth F , Strydom, Nadine A , Peer, Nasreen
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:6490 , http://hdl.handle.net/10962/d1014585 , http://dx.doi.org/10.1590/sajs.2014/20140011
- Description: Following the first description of living marine stromatolites along the South African east coast, new investigations along the south coast have revealed the occurrence of extensive fields of actively calcifying stromatolites. These stromatolites have been recorded at regular distances along a 200-km stretch of coastline, from Cape Recife in the east to the Storms River mouth in the west, with the highest density found between Schoenmakerskop and the Maitland River mouth. All active stromatolites are associated with freshwater seepage streams flowing from the dune cordon, which form rimstone dams and other accretions capable of retaining water in the supratidal platform. Resulting pools can reach a maximum depth of about 1 m and constitute a unique ecosystem in which freshwater and marine organisms alternate their dominance in response to vertical mixing and the balance between freshwater versus marine inflow. Although the factors controlling stromatolite growth are yet to be determined, nitrogen appears to be supplied mainly via the dune seeps. The epibenthic algal community within stromatolite pools is generally co-dominated by cyanobacteria and chlorophytes, with minimal diatom contribution.
- Full Text:
- Date Issued: 2014
Turning the lens on the adolescent suicide
- Authors: De Monk, Ingrid Venessia
- Date: 2014
- Subjects: Teenagers -- Suicidal behavior South Africa -- Port Elizabeth , School children -- Mental health services -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9582 , http://hdl.handle.net/10948/d1020791
- Description: In South Africa, suicidal behaviour in the younger generations has become rapidly part of a major public health problem. It is a well-known fact that adolescence is a critical period of progression in a teenager’s development which makes them more susceptible and vulnerable to suicide. Statistics have shown that there has been an increase in suicide among adolescents within the last decade (Schlebusch, 2005). The main aim of this research study is to explore the perceptions of adolescents regarding the factors that contribute to adolescent suicide. This study reviews literature concerning various risks factors for adolescent suicidality. It also described major social and psychological theories of suicide and the extent to which these studies support the importance to adolescent suicide. In the literature review theories of Bronfenbrenner’s Ecological Systems Theory, Durkheim’s sociological theory of suicide, Freud’s psychological perspective and Baumeister’s Escape Theory were discussed. A qualitative research design will be used by using visual participatory methodology techniques namely photo voice and reflective writing. A sample of 12 grade 11 learners, male and female, was purposely selected to participate in the research study. The focus of the study is to investigate the risk factors underlying adolescent suicidal behaviour in schools in the Northern Areas of Port Elizabeth, as well as to explore the stressors experienced by adolescents that could contribute to them having a higher suicide risk. Another focus point will be to look at prevention strategies as an antipode for suicidal behaviour. The main findings that emerged from the data analysis include contributing factors namely: socio-economic factors, personal factors, psychological factors and educational and school-related factors. The main prevention strategy themes emerged from findings derived from the data and include: parental involvement, religion, professional help and support groups and confiding in someone that you trust.
- Full Text:
- Date Issued: 2014
- Authors: De Monk, Ingrid Venessia
- Date: 2014
- Subjects: Teenagers -- Suicidal behavior South Africa -- Port Elizabeth , School children -- Mental health services -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9582 , http://hdl.handle.net/10948/d1020791
- Description: In South Africa, suicidal behaviour in the younger generations has become rapidly part of a major public health problem. It is a well-known fact that adolescence is a critical period of progression in a teenager’s development which makes them more susceptible and vulnerable to suicide. Statistics have shown that there has been an increase in suicide among adolescents within the last decade (Schlebusch, 2005). The main aim of this research study is to explore the perceptions of adolescents regarding the factors that contribute to adolescent suicide. This study reviews literature concerning various risks factors for adolescent suicidality. It also described major social and psychological theories of suicide and the extent to which these studies support the importance to adolescent suicide. In the literature review theories of Bronfenbrenner’s Ecological Systems Theory, Durkheim’s sociological theory of suicide, Freud’s psychological perspective and Baumeister’s Escape Theory were discussed. A qualitative research design will be used by using visual participatory methodology techniques namely photo voice and reflective writing. A sample of 12 grade 11 learners, male and female, was purposely selected to participate in the research study. The focus of the study is to investigate the risk factors underlying adolescent suicidal behaviour in schools in the Northern Areas of Port Elizabeth, as well as to explore the stressors experienced by adolescents that could contribute to them having a higher suicide risk. Another focus point will be to look at prevention strategies as an antipode for suicidal behaviour. The main findings that emerged from the data analysis include contributing factors namely: socio-economic factors, personal factors, psychological factors and educational and school-related factors. The main prevention strategy themes emerged from findings derived from the data and include: parental involvement, religion, professional help and support groups and confiding in someone that you trust.
- Full Text:
- Date Issued: 2014
Unclogging the wheels: how the shift from politics to law affects Africa's relationship with the international system
- Authors: Juma, Laurence
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127123 , vital:35958 , https://heinonline.org/HOL/Page?handle=hein.journals/tlcp23amp;div=17amp;g_sent=1amp;casa_token=amp;collection=journals
- Description: Gone are the days when scholars debated whether international law was really law and whether the adjudicatory organs of the international system could effectuate the demands of the international rule of law. 1 This old time debate has, in recent times, given way to temperate and yet decisive acknowledgement of the legal authority of institutions resident within the international system.
- Full Text: false
- Date Issued: 2014
- Authors: Juma, Laurence
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127123 , vital:35958 , https://heinonline.org/HOL/Page?handle=hein.journals/tlcp23amp;div=17amp;g_sent=1amp;casa_token=amp;collection=journals
- Description: Gone are the days when scholars debated whether international law was really law and whether the adjudicatory organs of the international system could effectuate the demands of the international rule of law. 1 This old time debate has, in recent times, given way to temperate and yet decisive acknowledgement of the legal authority of institutions resident within the international system.
- Full Text: false
- Date Issued: 2014
Understanding and modelling of surface and groundwater interactions
- Authors: Tanner, Jane Louise
- Date: 2014
- Subjects: Groundwater -- South Africa , Water-supply -- Management , Integrated water development , Hydrogeology , Water resources development -- South Africa , Water -- Analysis , Groundwater -- Management , Watersheds -- South Africa , Hydrologic models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6043 , http://hdl.handle.net/10962/d1012994
- Description: The connections between surface water and groundwater systems remain poorly understood in many catchments throughout the world and yet they are fundamental to effectively managing water resources. Managing water resources in an integrated manner is not straightforward, particularly if both resources are being utilised, and especially in those regions that suffer problems of data scarcity. This study explores some of the principle issues associated with understanding and practically modelling surface and groundwater interactions. In South Africa, there remains much controversy over the most appropriate type of integrated model to be used and the way forward in terms of the development of the discipline; part of the disagreement stems from the fact that we cannot validate models adequately. This is largely due to traditional forms of model testing having limited power as it is difficult to differentiate between the uncertainties within different model structures, different sets of alternative parameter values and in the input data used to run the model. While model structural uncertainties are important to consider, the uncertainty from input data error together with parameter estimation error are often more significant to the overall residual error, and essential to consider if we want to achieve reliable predictions for water resource decisions. While new philosophies and theories on modelling and results validation have been developed (Beven, 2002; Gupta et al., 2008), in many cases models are not only still being validated and compared using sparse and uncertain datasets, but also expected to produce reliable predictions based on the flawed data. The approach in this study is focused on fundamental understanding of hydrological systems rather than calibration based modelling and promotes the use of all the available 'hard' and 'soft' data together with thoughtful conceptual examination of the processes occurring in an environment to ensure as far as possible that a model is generating sensible results by simulating the correct processes. The first part of the thesis focuses on characterising the 'typical' interaction environments found in South Africa. It was found that many traditional perceptual models are not necessarily applicable to South African conditions, largely due to the relative importance of unsaturated zone processes and the complexity of the dominantly fractured rock environments. The interaction environments were categorised into four main 'types' of environment. These include karst, primary, fractured rock (secondary), and alluvial environments. Processes critical to Integrated Water Resource Management (IWRM) were defined within each interaction type as a guideline to setting a model up to realistically represent the dominant processes in the respective settings. The second part of the thesis addressed the application and evaluation of the modified Pitman model (Hughes, 2004), which allows for surface and groundwater interaction behaviour at the catchment scale to be simulated. The issue is whether, given the different sources of uncertainty in the modelling process, we can differentiate one conceptual flow path from another in trying to refine the understanding and consequently have more faith in model predictions. Seven example catchments were selected from around South Africa to assess whether reliable integrated assessments can be carried out given the existing data. Specific catchment perceptual models were used to identify the critical processes occurring in each setting and the Pitman model was assessed on whether it could represent them (structural uncertainty). The available knowledge of specific environments or catchments was then examined in an attempt to resolve the parameter uncertainty present within each catchment and ensure the subsequent model setup was correctly representing the process understanding as far as possible. The confidence in the quantitative results inevitably varied with the amount and quality of the data available. While the model was deemed to be robust based on the behavioural results obtained in the majority of the case studies, in many cases a quantitative validation of the outputs was just not possible based on the available data. In these cases, the model was judged on its ability to represent the conceptualisation of the processes occurring in the catchments. While the lack of appropriate data means there will always be considerable uncertainty surrounding model validation, it can be argued that improved process understanding in an environment can be used to validate model outcomes to a degree, by assessing whether a model is getting the right results for the right reasons. Many water resource decisions are still made without adequate account being taken of the uncertainties inherent in assessing the response of hydrological systems. Certainly, with all the possible sources of uncertainty in a data scarce country such as South Africa, pure calibration based modelling is unlikely to produce reliable information for water resource managers as it can produce the right results for the wrong reasons. Thus it becomes essential to incorporate conceptual thinking into the modelling process, so that at the very least we are able to conclude that a model generates estimates that are consistent with, and reflect, our understanding (however limited) of the catchment processes. It is fairly clear that achieving the optimum model of a hydrological system may be fraught with difficulty, if not impossible. This makes it very difficult from a practitioner's point of view to decide which model and uncertainty estimation method to use. According to Beven (2009), this may be a transitional problem and in the future it may become clearer as we learn more about how to estimate the uncertainties associated with hydrological systems. Until then, a better understanding of the fundamental and most critical hydrogeological processes should be used to critically test and improve model predictions as far as possible. A major focus of the study was to identify whether the modified Pitman model could provide a practical tool for water resource managers by reliably determining the available water resource. The incorporation of surface and groundwater interaction routines seems to have resulted in a more robust and realistic model of basin hydrology. The overall conclusion is that the model, although simplified, is capable of representing the catchment scale processes that occur under most South African conditions.
- Full Text:
- Date Issued: 2014
- Authors: Tanner, Jane Louise
- Date: 2014
- Subjects: Groundwater -- South Africa , Water-supply -- Management , Integrated water development , Hydrogeology , Water resources development -- South Africa , Water -- Analysis , Groundwater -- Management , Watersheds -- South Africa , Hydrologic models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6043 , http://hdl.handle.net/10962/d1012994
- Description: The connections between surface water and groundwater systems remain poorly understood in many catchments throughout the world and yet they are fundamental to effectively managing water resources. Managing water resources in an integrated manner is not straightforward, particularly if both resources are being utilised, and especially in those regions that suffer problems of data scarcity. This study explores some of the principle issues associated with understanding and practically modelling surface and groundwater interactions. In South Africa, there remains much controversy over the most appropriate type of integrated model to be used and the way forward in terms of the development of the discipline; part of the disagreement stems from the fact that we cannot validate models adequately. This is largely due to traditional forms of model testing having limited power as it is difficult to differentiate between the uncertainties within different model structures, different sets of alternative parameter values and in the input data used to run the model. While model structural uncertainties are important to consider, the uncertainty from input data error together with parameter estimation error are often more significant to the overall residual error, and essential to consider if we want to achieve reliable predictions for water resource decisions. While new philosophies and theories on modelling and results validation have been developed (Beven, 2002; Gupta et al., 2008), in many cases models are not only still being validated and compared using sparse and uncertain datasets, but also expected to produce reliable predictions based on the flawed data. The approach in this study is focused on fundamental understanding of hydrological systems rather than calibration based modelling and promotes the use of all the available 'hard' and 'soft' data together with thoughtful conceptual examination of the processes occurring in an environment to ensure as far as possible that a model is generating sensible results by simulating the correct processes. The first part of the thesis focuses on characterising the 'typical' interaction environments found in South Africa. It was found that many traditional perceptual models are not necessarily applicable to South African conditions, largely due to the relative importance of unsaturated zone processes and the complexity of the dominantly fractured rock environments. The interaction environments were categorised into four main 'types' of environment. These include karst, primary, fractured rock (secondary), and alluvial environments. Processes critical to Integrated Water Resource Management (IWRM) were defined within each interaction type as a guideline to setting a model up to realistically represent the dominant processes in the respective settings. The second part of the thesis addressed the application and evaluation of the modified Pitman model (Hughes, 2004), which allows for surface and groundwater interaction behaviour at the catchment scale to be simulated. The issue is whether, given the different sources of uncertainty in the modelling process, we can differentiate one conceptual flow path from another in trying to refine the understanding and consequently have more faith in model predictions. Seven example catchments were selected from around South Africa to assess whether reliable integrated assessments can be carried out given the existing data. Specific catchment perceptual models were used to identify the critical processes occurring in each setting and the Pitman model was assessed on whether it could represent them (structural uncertainty). The available knowledge of specific environments or catchments was then examined in an attempt to resolve the parameter uncertainty present within each catchment and ensure the subsequent model setup was correctly representing the process understanding as far as possible. The confidence in the quantitative results inevitably varied with the amount and quality of the data available. While the model was deemed to be robust based on the behavioural results obtained in the majority of the case studies, in many cases a quantitative validation of the outputs was just not possible based on the available data. In these cases, the model was judged on its ability to represent the conceptualisation of the processes occurring in the catchments. While the lack of appropriate data means there will always be considerable uncertainty surrounding model validation, it can be argued that improved process understanding in an environment can be used to validate model outcomes to a degree, by assessing whether a model is getting the right results for the right reasons. Many water resource decisions are still made without adequate account being taken of the uncertainties inherent in assessing the response of hydrological systems. Certainly, with all the possible sources of uncertainty in a data scarce country such as South Africa, pure calibration based modelling is unlikely to produce reliable information for water resource managers as it can produce the right results for the wrong reasons. Thus it becomes essential to incorporate conceptual thinking into the modelling process, so that at the very least we are able to conclude that a model generates estimates that are consistent with, and reflect, our understanding (however limited) of the catchment processes. It is fairly clear that achieving the optimum model of a hydrological system may be fraught with difficulty, if not impossible. This makes it very difficult from a practitioner's point of view to decide which model and uncertainty estimation method to use. According to Beven (2009), this may be a transitional problem and in the future it may become clearer as we learn more about how to estimate the uncertainties associated with hydrological systems. Until then, a better understanding of the fundamental and most critical hydrogeological processes should be used to critically test and improve model predictions as far as possible. A major focus of the study was to identify whether the modified Pitman model could provide a practical tool for water resource managers by reliably determining the available water resource. The incorporation of surface and groundwater interaction routines seems to have resulted in a more robust and realistic model of basin hydrology. The overall conclusion is that the model, although simplified, is capable of representing the catchment scale processes that occur under most South African conditions.
- Full Text:
- Date Issued: 2014
Understanding change and implications of divisional management model (DMM ) in a merged multi- campus University in South Africa
- Authors: Mantashe, Lunga Xolisa
- Date: 2014
- Subjects: Organizational change
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6103 , vital:29491
- Description: The study sought to understand change and transition in a multi-merged campus university in South Africa. Specifically the objectives were to understand the Human Resource (HR) plan, how it is being rolled out, the reactions of workers to it, the effects of the plan on workers and the processes put in place to mitigate, rather than aggravate, the current and foreseeable consequences of the Human Resource plan. A qualitative case study was used and focus groups and semi-structured interviews (triangulated with observation and document analysis) were used on a purposive sample of unions and the university HR official in one campus. The researcher found that there is no organogram which acts as a framework wherein all workers in respective campuses shall fit in. additionally, there is no staff transition plan and harmonisation of conditions of service policy that is agreed upon. Though it seemed there were some mechanisms to attenuate the effects of the HR plan (possible retrenchments, loss of morale, uncertainty, stress, doubt and the like) such as voluntary service package, there were areas of concern about the lack of a properly and widely circulated plan, and the absence of plans to transition staff throughout the process of change. Consequently, the researcher recommended at the end of the study that there must be a change management leadership in each campus to drive transition, a creation of proper communication networks, institution of campus indabas, a design of a transition plan, harmonisation approaches, migration of institutional items to an institutional site and the facilitation of recognition agreements for those unions which are still recognise in the premerger manner.
- Full Text:
- Date Issued: 2014
- Authors: Mantashe, Lunga Xolisa
- Date: 2014
- Subjects: Organizational change
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10353/6103 , vital:29491
- Description: The study sought to understand change and transition in a multi-merged campus university in South Africa. Specifically the objectives were to understand the Human Resource (HR) plan, how it is being rolled out, the reactions of workers to it, the effects of the plan on workers and the processes put in place to mitigate, rather than aggravate, the current and foreseeable consequences of the Human Resource plan. A qualitative case study was used and focus groups and semi-structured interviews (triangulated with observation and document analysis) were used on a purposive sample of unions and the university HR official in one campus. The researcher found that there is no organogram which acts as a framework wherein all workers in respective campuses shall fit in. additionally, there is no staff transition plan and harmonisation of conditions of service policy that is agreed upon. Though it seemed there were some mechanisms to attenuate the effects of the HR plan (possible retrenchments, loss of morale, uncertainty, stress, doubt and the like) such as voluntary service package, there were areas of concern about the lack of a properly and widely circulated plan, and the absence of plans to transition staff throughout the process of change. Consequently, the researcher recommended at the end of the study that there must be a change management leadership in each campus to drive transition, a creation of proper communication networks, institution of campus indabas, a design of a transition plan, harmonisation approaches, migration of institutional items to an institutional site and the facilitation of recognition agreements for those unions which are still recognise in the premerger manner.
- Full Text:
- Date Issued: 2014
Understanding development aid and state autonomy : the case of European Union budget support to Mozambique
- Authors: Ndlovu, Ana Admiração
- Date: 2014
- Subjects: Economic assistance, European -- Mozambique , Economic development -- Mozambique , Mozambique -- Economic conditions , Autonomy , Budget -- Mozambique
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3378 , http://hdl.handle.net/10962/d1013218
- Description: Post-colonial states in Africa continue to pursue nation-building and socio-economic development. This process is taking place with the sustained support of global agencies in terms of development cooperation, assistance and aid. Insofar as an endogenous development path which speaks to national priorities can be formulated and implemented by post-colonial states, their relationship with these agencies raises serious questions about such a path if the relationship entails dependence and indeed subordination of post-colonial states. This raises important questions about state autonomy under post-colonial conditions and the possibility of autonomy being compromised. In this light, the thesis examines European Union budget support to Mozambique and, in particular, the relationship between EU budget support and Mozambique state autonomy in pursuing national development. This is particularly pertinent given the massive dependence of the Mozambican state on foreign funding (notably EU funding) with specific regard to the national budget. Despite the broad claims existing in the prevailing literature that nation-state autonomy is seriously undermined in and through the international development system, the thesis argues against reductionist arguments that simply posit post-colonial states as mere instruments of global forces. This system, including European Union budget support, does indeed set the conditions of existence for post-colonial states such as Mozambique. But autonomy is necessarily relative and is subject to different forms and degrees. Ultimately, it is through empirical investigation that the specific form and degree of autonomy can be pinpointed and understood. The thesis contributes to this endeavour and suggests that the relationship between European budget support and Mozambican state autonomy is more complex and tension-riddled than the prevailing literature would seem to suggest.
- Full Text:
- Date Issued: 2014
- Authors: Ndlovu, Ana Admiração
- Date: 2014
- Subjects: Economic assistance, European -- Mozambique , Economic development -- Mozambique , Mozambique -- Economic conditions , Autonomy , Budget -- Mozambique
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3378 , http://hdl.handle.net/10962/d1013218
- Description: Post-colonial states in Africa continue to pursue nation-building and socio-economic development. This process is taking place with the sustained support of global agencies in terms of development cooperation, assistance and aid. Insofar as an endogenous development path which speaks to national priorities can be formulated and implemented by post-colonial states, their relationship with these agencies raises serious questions about such a path if the relationship entails dependence and indeed subordination of post-colonial states. This raises important questions about state autonomy under post-colonial conditions and the possibility of autonomy being compromised. In this light, the thesis examines European Union budget support to Mozambique and, in particular, the relationship between EU budget support and Mozambique state autonomy in pursuing national development. This is particularly pertinent given the massive dependence of the Mozambican state on foreign funding (notably EU funding) with specific regard to the national budget. Despite the broad claims existing in the prevailing literature that nation-state autonomy is seriously undermined in and through the international development system, the thesis argues against reductionist arguments that simply posit post-colonial states as mere instruments of global forces. This system, including European Union budget support, does indeed set the conditions of existence for post-colonial states such as Mozambique. But autonomy is necessarily relative and is subject to different forms and degrees. Ultimately, it is through empirical investigation that the specific form and degree of autonomy can be pinpointed and understood. The thesis contributes to this endeavour and suggests that the relationship between European budget support and Mozambican state autonomy is more complex and tension-riddled than the prevailing literature would seem to suggest.
- Full Text:
- Date Issued: 2014
Understanding educators' and learners' perceptions and experiences of their participation in Science Fairs/Expos : a South African case study.
- Authors: Kahenge, Wendelina Nambahu
- Date: 2014
- Subjects: Science fairs -- South Africa -- Grahamstown , Science -- Study and teaching -- South Africa -- Grahamstown , Vocational guidance -- South Africa -- Grahamstown , School children -- South Africa -- Attitudes , Teachers -- South Africa -- Attitudes , Teacher effectiveness -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1981 , http://hdl.handle.net/10962/d1013130
- Description: The rationale behind Science Expos is to develop and empower learners to be able to identify problems and find solutions (Eskom Expo Project Guide Book, 2013). It is believed that involvement in Science Expos arouses learners' interest to pursue science related careers. But despite these ideals, there is still poor participation in Science Expos by educators and learners. I conducted this case study in five schools in Grahamstown, Eastern Cape, South Africa. The purpose of this study was to understand educators' and learners' perceptions and experiences of their participation in Science Expos. The case study was designed within an interpretive paradigm. The data were generated, triangulated and validated by a variety of methods, namely, document analysis, interviews (semi-structured and focus group) and observations. The main findings of the study were that learners who participate in Science Expos attend workshops organised by Scifest and SAEON office with the help of some of the educators and lecturers from Rhodes University. Learners' participation was influenced and assisted by the educators and peers with whom they were able to communicate and share their projects with. It emerged from the study that, as a result of participating in Science Expos, educators (teachers) and learners were exposed to a wide variety of scientific investigations and skills that are necessary for their classroom based-scientific investigations. It also emerged from this study that educators and learners face the challenge of a lack of motivation; insufficient support from schools and parents; time constraints to support learners in their participation and a lack of knowledge among some educators on their learners' projects. Some learners are even discouraged from participating in Science Expos by their peers on the grounds that they have no chance of winning. Teachers therefore require continuous mentorship and capacity building in order to encourage their learners to partake.
- Full Text:
- Date Issued: 2014
- Authors: Kahenge, Wendelina Nambahu
- Date: 2014
- Subjects: Science fairs -- South Africa -- Grahamstown , Science -- Study and teaching -- South Africa -- Grahamstown , Vocational guidance -- South Africa -- Grahamstown , School children -- South Africa -- Attitudes , Teachers -- South Africa -- Attitudes , Teacher effectiveness -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1981 , http://hdl.handle.net/10962/d1013130
- Description: The rationale behind Science Expos is to develop and empower learners to be able to identify problems and find solutions (Eskom Expo Project Guide Book, 2013). It is believed that involvement in Science Expos arouses learners' interest to pursue science related careers. But despite these ideals, there is still poor participation in Science Expos by educators and learners. I conducted this case study in five schools in Grahamstown, Eastern Cape, South Africa. The purpose of this study was to understand educators' and learners' perceptions and experiences of their participation in Science Expos. The case study was designed within an interpretive paradigm. The data were generated, triangulated and validated by a variety of methods, namely, document analysis, interviews (semi-structured and focus group) and observations. The main findings of the study were that learners who participate in Science Expos attend workshops organised by Scifest and SAEON office with the help of some of the educators and lecturers from Rhodes University. Learners' participation was influenced and assisted by the educators and peers with whom they were able to communicate and share their projects with. It emerged from the study that, as a result of participating in Science Expos, educators (teachers) and learners were exposed to a wide variety of scientific investigations and skills that are necessary for their classroom based-scientific investigations. It also emerged from this study that educators and learners face the challenge of a lack of motivation; insufficient support from schools and parents; time constraints to support learners in their participation and a lack of knowledge among some educators on their learners' projects. Some learners are even discouraged from participating in Science Expos by their peers on the grounds that they have no chance of winning. Teachers therefore require continuous mentorship and capacity building in order to encourage their learners to partake.
- Full Text:
- Date Issued: 2014
Understanding food security in a perfect storm: an ecosystem services approach
- Poppy, G M, Chiotha, S, Eigenbrod, Felix, Harvey, Celia A, Honza´k, M, Hudson, Malcolm D, Jarvis, A, Madise, Nyovani J, Schreckenberg, Kate, Shackleton, Charlie M, Villa, F, Dawson, Terrence P
- Authors: Poppy, G M , Chiotha, S , Eigenbrod, Felix , Harvey, Celia A , Honza´k, M , Hudson, Malcolm D , Jarvis, A , Madise, Nyovani J , Schreckenberg, Kate , Shackleton, Charlie M , Villa, F , Dawson, Terrence P
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398423 , vital:69410 , xlink:href="https://doi.org/10.1098/rstb.2012.0288"
- Description: Achieving food security in a ‘perfect storm’ scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.
- Full Text:
- Date Issued: 2014
- Authors: Poppy, G M , Chiotha, S , Eigenbrod, Felix , Harvey, Celia A , Honza´k, M , Hudson, Malcolm D , Jarvis, A , Madise, Nyovani J , Schreckenberg, Kate , Shackleton, Charlie M , Villa, F , Dawson, Terrence P
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398423 , vital:69410 , xlink:href="https://doi.org/10.1098/rstb.2012.0288"
- Description: Achieving food security in a ‘perfect storm’ scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.
- Full Text:
- Date Issued: 2014
Understanding how trainee teachers engage with prior everyday knowledge and experience associated with biological concepts during integrated natural science education 5-7 : a case study
- Authors: Enghono, Albertina Magano
- Date: 2014
- Subjects: Biology teachers -- Training of -- Namibia -- Case studies Teacher educators -- Training of -- Case studies Teachers -- Training of -- Namibia -- Case studies Education -- Namibia -- Case studies Prior learning -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1970 , http://hdl.handle.net/10962/d1011972
- Description: Since the Namibian independence in 1990, the education system has undergone some major revamping which involved the adoption of social constructivist perspectives in the teaching and learning of sciences. This learning theory acknowledges learners’ background prior knowledge as valuable tools in the effective construction of science concepts during lessons. A corollary is that the socio-cultural circumstances of learners might negatively influence the way learners construct new knowledge in the science classroom if they are not taken into consideration. This study was thus prompted by the need to understand how trainee science teachers engage with prior everyday knowledge and experiences, so as to enhance the conceptual development of biological concepts. The study was qualitative and it was underpinned by an interpretive paradigm with some elements of action research. Science trainee teachers at Katima Mulilo, Unam Campus were used as research participants. The techniques used to gather data included document analysis, brainstorming, observation, audio-visual, microteaching and semi-structured interviews. The results of this study showed that the changes that occurred during microteaching practices of the four trainee teachers involved in the study reflected their professional development in this approach. However, it emerged that prior everyday knowledge can be both a barrier and enabler to the construction of meaningful teaching and learning; hence its oversight may lead to instructional failures. The findings also indicated that selected platforms are essential to enable trainee teachers to incorporate prior everyday knowledge and experiences into the teaching of Western science. However, larger scale study should be conducted in order to deepen the understanding of the topic.
- Full Text:
- Date Issued: 2014
- Authors: Enghono, Albertina Magano
- Date: 2014
- Subjects: Biology teachers -- Training of -- Namibia -- Case studies Teacher educators -- Training of -- Case studies Teachers -- Training of -- Namibia -- Case studies Education -- Namibia -- Case studies Prior learning -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1970 , http://hdl.handle.net/10962/d1011972
- Description: Since the Namibian independence in 1990, the education system has undergone some major revamping which involved the adoption of social constructivist perspectives in the teaching and learning of sciences. This learning theory acknowledges learners’ background prior knowledge as valuable tools in the effective construction of science concepts during lessons. A corollary is that the socio-cultural circumstances of learners might negatively influence the way learners construct new knowledge in the science classroom if they are not taken into consideration. This study was thus prompted by the need to understand how trainee science teachers engage with prior everyday knowledge and experiences, so as to enhance the conceptual development of biological concepts. The study was qualitative and it was underpinned by an interpretive paradigm with some elements of action research. Science trainee teachers at Katima Mulilo, Unam Campus were used as research participants. The techniques used to gather data included document analysis, brainstorming, observation, audio-visual, microteaching and semi-structured interviews. The results of this study showed that the changes that occurred during microteaching practices of the four trainee teachers involved in the study reflected their professional development in this approach. However, it emerged that prior everyday knowledge can be both a barrier and enabler to the construction of meaningful teaching and learning; hence its oversight may lead to instructional failures. The findings also indicated that selected platforms are essential to enable trainee teachers to incorporate prior everyday knowledge and experiences into the teaching of Western science. However, larger scale study should be conducted in order to deepen the understanding of the topic.
- Full Text:
- Date Issued: 2014
Understanding the livelihoods of child-grant mothers in Sinathingi in KwaZulu-Natal, South Africa
- Motsetse, Matsepo Nomathemba
- Authors: Motsetse, Matsepo Nomathemba
- Date: 2014
- Subjects: Welfare recipients -- South Africa -- KwaZulu-Natal , Social security -- South Africa , Family policy -- South Africa , Women -- South Africa -- KwaZulu-Natal -- Social conditions , Women -- South Africa -- KwaZulu-Natal -- Economic conditions , Poverty -- South Africa , Income -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3380 , http://hdl.handle.net/10962/d1013284
- Description: The main focus of this thesis is the child support grant, as part of a broader social security system, in post-apartheid South Africa. Since the end of apartheid of 1994, the new South African government has sought to redress the racial imbalances and inequalities of the past by engaging in measures of redistribution. Central to this pursuit of redistribution has been a restructured system of social grants, of which the child support grant is the most significant. However, the post-apartheid government has adopted a largely neo-liberal macro-economic strategy such that social inequality and endemic poverty remain pervasive particularly amongst the African population, which includes the recipients of the child support grants. In adopting a sustainable livelihoods framework as the main theoretical perspective, the thesis seeks to understand the livelihoods of child support grant mothers in the face of conditions of extreme poverty. It does this through a localised study of twenty child grant mothers in Sinathingi Township in KwaZulu-Natal Province. In examining the livelihoods of these child-grant mothers, the thesis brings to the fore that mothers and their children do not exist as autonomous living units but are embedded in a broader set of social relations, including intra-household relations and relations with the fathers of the grant-children. It also demonstrates that child-grant mothers are not simply victims of structures of poverty in contemporary South Africa, but actively construct their livelihoods through a range of activities and strategies which show perseverance and ingenuity.
- Full Text:
- Date Issued: 2014
- Authors: Motsetse, Matsepo Nomathemba
- Date: 2014
- Subjects: Welfare recipients -- South Africa -- KwaZulu-Natal , Social security -- South Africa , Family policy -- South Africa , Women -- South Africa -- KwaZulu-Natal -- Social conditions , Women -- South Africa -- KwaZulu-Natal -- Economic conditions , Poverty -- South Africa , Income -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3380 , http://hdl.handle.net/10962/d1013284
- Description: The main focus of this thesis is the child support grant, as part of a broader social security system, in post-apartheid South Africa. Since the end of apartheid of 1994, the new South African government has sought to redress the racial imbalances and inequalities of the past by engaging in measures of redistribution. Central to this pursuit of redistribution has been a restructured system of social grants, of which the child support grant is the most significant. However, the post-apartheid government has adopted a largely neo-liberal macro-economic strategy such that social inequality and endemic poverty remain pervasive particularly amongst the African population, which includes the recipients of the child support grants. In adopting a sustainable livelihoods framework as the main theoretical perspective, the thesis seeks to understand the livelihoods of child support grant mothers in the face of conditions of extreme poverty. It does this through a localised study of twenty child grant mothers in Sinathingi Township in KwaZulu-Natal Province. In examining the livelihoods of these child-grant mothers, the thesis brings to the fore that mothers and their children do not exist as autonomous living units but are embedded in a broader set of social relations, including intra-household relations and relations with the fathers of the grant-children. It also demonstrates that child-grant mothers are not simply victims of structures of poverty in contemporary South Africa, but actively construct their livelihoods through a range of activities and strategies which show perseverance and ingenuity.
- Full Text:
- Date Issued: 2014
Understanding the replication biology of Providence virus: elucidating the function of non-structural proteins
- Authors: Nakayinga, Ritah
- Date: 2014
- Subjects: Insects Viruses , Viruses Reproduction , Tombusviridae , RNA viruses , RNA polymerases
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/193930 , vital:45408
- Description: Tetraviruses are non-enveloped, small insect RNA viruses with a single stranded positive RNA genome that is either monopartite or bipartite. Providence virus (PrV) is the only member of the three tetravirus families with a viral replicase similar to the replicases of tombusviruses and umbraviruses. The principle aim of this thesis was to study PrV replication, focusing on subcellular localization and potential interactions between PrV replication proteins. The first objective of this study was to generate an anti-p104 antibody that does not cross-react with p40. Expression of the C-terminal portion of p104 in E. coli resulted in no detectable protein. Further expression in an insect cell based expression system resulted in the production of an insoluble protein. Attempts to improve protein solubility with a range of solubilization treatments were unsuccessful. Bioinformatic analysis was used to detect an antigenic region at the C-terminus of p104 and the peptide was used to raise anti-p104 antibodies. These antibodies did not detect native protein by western blot detection however they were used for immunoprecipitation. The establishment of the subcellular localization of PrV required two approaches; immunofluorescence in persistently infected Helicoverpa zea MG8 cells using antip40 and anti-dsRNA antibodies and the expression of EGFP-replicase fusion protein in Spodoptera frugiperda Sf9 cells. Replication of PrV was found to take place in cytosolic punctate structures. Co-immunoprecipitation experiments revealed that p40 self-interacts and interacts with p104. Bioinformatic analysis of PrV p104 suggests that the RdRp is similar to viral RdRps of the carmo-like supergroup II. Potential RNA binding regions are present within p104. A potential p40 interaction domain that shares hydrophilic and surface exposed properties with the TBSV p33 interaction domain is present. A putative arginine-rich region and disordered C-terminal region is present in p130. In conclusion, PrV p104 is the viral replicase. The resemblance of the expression strategy and putative functional domains with tombusviruses and umbraviruses suggest that PrV replication is related to the replication system of the tombusviruses and umbraviruses. This has led to propose that tetravirus replication strategies are diverse and raises questions on the origin and evolution of PrV. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Biotechnology, 2014
- Full Text:
- Date Issued: 2014
- Authors: Nakayinga, Ritah
- Date: 2014
- Subjects: Insects Viruses , Viruses Reproduction , Tombusviridae , RNA viruses , RNA polymerases
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/193930 , vital:45408
- Description: Tetraviruses are non-enveloped, small insect RNA viruses with a single stranded positive RNA genome that is either monopartite or bipartite. Providence virus (PrV) is the only member of the three tetravirus families with a viral replicase similar to the replicases of tombusviruses and umbraviruses. The principle aim of this thesis was to study PrV replication, focusing on subcellular localization and potential interactions between PrV replication proteins. The first objective of this study was to generate an anti-p104 antibody that does not cross-react with p40. Expression of the C-terminal portion of p104 in E. coli resulted in no detectable protein. Further expression in an insect cell based expression system resulted in the production of an insoluble protein. Attempts to improve protein solubility with a range of solubilization treatments were unsuccessful. Bioinformatic analysis was used to detect an antigenic region at the C-terminus of p104 and the peptide was used to raise anti-p104 antibodies. These antibodies did not detect native protein by western blot detection however they were used for immunoprecipitation. The establishment of the subcellular localization of PrV required two approaches; immunofluorescence in persistently infected Helicoverpa zea MG8 cells using antip40 and anti-dsRNA antibodies and the expression of EGFP-replicase fusion protein in Spodoptera frugiperda Sf9 cells. Replication of PrV was found to take place in cytosolic punctate structures. Co-immunoprecipitation experiments revealed that p40 self-interacts and interacts with p104. Bioinformatic analysis of PrV p104 suggests that the RdRp is similar to viral RdRps of the carmo-like supergroup II. Potential RNA binding regions are present within p104. A potential p40 interaction domain that shares hydrophilic and surface exposed properties with the TBSV p33 interaction domain is present. A putative arginine-rich region and disordered C-terminal region is present in p130. In conclusion, PrV p104 is the viral replicase. The resemblance of the expression strategy and putative functional domains with tombusviruses and umbraviruses suggest that PrV replication is related to the replication system of the tombusviruses and umbraviruses. This has led to propose that tetravirus replication strategies are diverse and raises questions on the origin and evolution of PrV. , Thesis (PhD) -- Faculty of Science, Biochemistry, Microbiology and Biotechnology, 2014
- Full Text:
- Date Issued: 2014
Understanding the sexual practices of medically circumcised males in the context of HIV and AIDS : a study in Harare Zimbabwe
- Authors: Chamuka, Paidashe
- Date: 2014
- Subjects: Circumcision -- Zimbabwe , Men -- Sexual behavior -- Zimbabwe -- Case studies , AIDS (Disease) -- Zimbabwe -- Prevention , HIV infections -- South Africa -- Prevention
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3363 , http://hdl.handle.net/10962/d1011745 , Circumcision -- Zimbabwe , Men -- Sexual behavior -- Zimbabwe -- Case studies , AIDS (Disease) -- Zimbabwe -- Prevention , HIV infections -- South Africa -- Prevention
- Description: Zimbabwe is one of the priority countries nominated by the World Health Organisation and the Joint United Nations Programme on HIV and AIDS to adopt and implement voluntary medical male circumcision (VMMC) because of its high rate of HIV prevalence and its low level of male circumcision. VMMC, which was introduced in Zimbabwe in 2009, is a new HIV prevention method which reportedly offers partial protection of about 60 percent for circumcised males with respect to contracting HIV through sexual relations. The other key prevention method, namely the use of condoms consistently and correctly, has a protection rate of up to 95 percent. As a result, because of only partial protection, medically-circumcised men are encouraged to use condoms to decrease the chances of HIV infection. Concerns though have been raised about the possibility of risk compensation by circumcised males by way of increases in unsafe or risky sexual practices subsequent to circumcision and arising from perceptions of reduced risk through VMMC. This compensation may take the form of condom use aversion including when involved with concurrent sexual partners. If risk compensation does take place, this would lead to increases in HIV transmissions affecting not only the circumcised men but their sexual partners as well. The supposed effectiveness of VMMC as a HIV prevention method has been subjected to significant criticism and, as yet, no significant study has been undertaken in Zimbabwe on the relationship between VMMC, condom use, concurrent sexual partners and risk compensation. Based on a study of twenty-five medically-circumcised males in Harare, the capital of Zimbabwe, this thesis seeks to understand and explain the relationship between voluntary medical male circumcision and risky sexual practices with particular reference to condom use amongst men engaged in concurrent sexual partnerships. While the thesis finds evidence of risky sexual practices subsequent to circumcision, risk compensation does not seem to be particularly prevalent.
- Full Text:
- Date Issued: 2014
- Authors: Chamuka, Paidashe
- Date: 2014
- Subjects: Circumcision -- Zimbabwe , Men -- Sexual behavior -- Zimbabwe -- Case studies , AIDS (Disease) -- Zimbabwe -- Prevention , HIV infections -- South Africa -- Prevention
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3363 , http://hdl.handle.net/10962/d1011745 , Circumcision -- Zimbabwe , Men -- Sexual behavior -- Zimbabwe -- Case studies , AIDS (Disease) -- Zimbabwe -- Prevention , HIV infections -- South Africa -- Prevention
- Description: Zimbabwe is one of the priority countries nominated by the World Health Organisation and the Joint United Nations Programme on HIV and AIDS to adopt and implement voluntary medical male circumcision (VMMC) because of its high rate of HIV prevalence and its low level of male circumcision. VMMC, which was introduced in Zimbabwe in 2009, is a new HIV prevention method which reportedly offers partial protection of about 60 percent for circumcised males with respect to contracting HIV through sexual relations. The other key prevention method, namely the use of condoms consistently and correctly, has a protection rate of up to 95 percent. As a result, because of only partial protection, medically-circumcised men are encouraged to use condoms to decrease the chances of HIV infection. Concerns though have been raised about the possibility of risk compensation by circumcised males by way of increases in unsafe or risky sexual practices subsequent to circumcision and arising from perceptions of reduced risk through VMMC. This compensation may take the form of condom use aversion including when involved with concurrent sexual partners. If risk compensation does take place, this would lead to increases in HIV transmissions affecting not only the circumcised men but their sexual partners as well. The supposed effectiveness of VMMC as a HIV prevention method has been subjected to significant criticism and, as yet, no significant study has been undertaken in Zimbabwe on the relationship between VMMC, condom use, concurrent sexual partners and risk compensation. Based on a study of twenty-five medically-circumcised males in Harare, the capital of Zimbabwe, this thesis seeks to understand and explain the relationship between voluntary medical male circumcision and risky sexual practices with particular reference to condom use amongst men engaged in concurrent sexual partnerships. While the thesis finds evidence of risky sexual practices subsequent to circumcision, risk compensation does not seem to be particularly prevalent.
- Full Text:
- Date Issued: 2014
Undertaking to care and to protect : The experience of killing healthy homeless animals in South Africa
- Authors: Van Zyl, Henriette Louise
- Date: 2014
- Subjects: Animal welfare -- Moral and ethical aspects -- South Africa , Euthanasia of animals -- South Africa , Euthanasia of animals -- Psychological aspects , Human-animal relationships -- South Africa , Animal rights -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3245 , http://hdl.handle.net/10962/d1013577
- Description: Although animal welfare workers overwhelmingly describe themselves as animal lovers the exigencies of day to day animal welfare work often require that they perform euthanasia of healthy animals as part of welfare shelter management, and animal population control. In this research study, the particular burdens placed upon seven South Animal welfare workers who are required to rescue, care for, nurture and rehabilitate the animals in their care; while simultaneously being required to kill these same – often physically and behaviourally healthy - animals after a specific period of time, or in response to various logistical, procedural and practical intricacies, ranging from lack of space and resources to an unavailability of suitable homes; are explored from an interpretative phenomenological approach using the Interpretative Phenomenological Method (IPA), and from a South African perspective. It was found that animal-loving individuals engaged in the care and subsequent euthanasia of healthy animals report experiencing profound personal, interpersonal and professional and ideological (dis)stress related to guilt, sorrow, moral unease and horror. Four themes emerged from interview data, which are discussed in relation to relevant research and literature. Experiences in a South African context were found to be very much aligned with those reported in previous research and literature pertaining to this topic. In particular, it was found that there is a need to articulate specifically, and precisely the nature of the act. It is proposed that the term “Agapéthanasia” would be appropriate and useful in this field.
- Full Text:
- Date Issued: 2014
- Authors: Van Zyl, Henriette Louise
- Date: 2014
- Subjects: Animal welfare -- Moral and ethical aspects -- South Africa , Euthanasia of animals -- South Africa , Euthanasia of animals -- Psychological aspects , Human-animal relationships -- South Africa , Animal rights -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3245 , http://hdl.handle.net/10962/d1013577
- Description: Although animal welfare workers overwhelmingly describe themselves as animal lovers the exigencies of day to day animal welfare work often require that they perform euthanasia of healthy animals as part of welfare shelter management, and animal population control. In this research study, the particular burdens placed upon seven South Animal welfare workers who are required to rescue, care for, nurture and rehabilitate the animals in their care; while simultaneously being required to kill these same – often physically and behaviourally healthy - animals after a specific period of time, or in response to various logistical, procedural and practical intricacies, ranging from lack of space and resources to an unavailability of suitable homes; are explored from an interpretative phenomenological approach using the Interpretative Phenomenological Method (IPA), and from a South African perspective. It was found that animal-loving individuals engaged in the care and subsequent euthanasia of healthy animals report experiencing profound personal, interpersonal and professional and ideological (dis)stress related to guilt, sorrow, moral unease and horror. Four themes emerged from interview data, which are discussed in relation to relevant research and literature. Experiences in a South African context were found to be very much aligned with those reported in previous research and literature pertaining to this topic. In particular, it was found that there is a need to articulate specifically, and precisely the nature of the act. It is proposed that the term “Agapéthanasia” would be appropriate and useful in this field.
- Full Text:
- Date Issued: 2014
Unsymmetrically substituted nickel triazatetra-benzcorrole and phthalocynanine complexes
- Adegoke, Oluwasesan, Nyokong, Tebello
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189818 , vital:44934 , xlink:href="https://doi.org/10.1007/s10895-013-1317-4"
- Description: We report on the design and application of fluorescent nanoprobes based on the covalent linking of L-glutathione-capped CdSe@ZnS quantum dots (QDs) to newly synthesized unsymmetrically substituted nickel mercaptosuccinic acid triazatetra-benzcorrole (3) and phthalocyanine (4) complexes. Fluorescence quenching of the QDs occurred on conjugation to complexes 3 or 4. The nanoprobes were selectively screened in the presence of different cations and Hg2+ showed excellent affinity in “turning ON” the fluorescence of the nanoprobes. Experimental results showed that the sensitivity of QDs-4 towards Hg2+ was much higher than that of QDs-3 nanoprobe. The mechanism of reaction has been elucidated based on the ability of Hg2+ to coordinate with the sulphur atom of the Ni complex ring and apparently “turn ON” the fluorescence of the linked QDs.
- Full Text:
- Date Issued: 2014
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189818 , vital:44934 , xlink:href="https://doi.org/10.1007/s10895-013-1317-4"
- Description: We report on the design and application of fluorescent nanoprobes based on the covalent linking of L-glutathione-capped CdSe@ZnS quantum dots (QDs) to newly synthesized unsymmetrically substituted nickel mercaptosuccinic acid triazatetra-benzcorrole (3) and phthalocyanine (4) complexes. Fluorescence quenching of the QDs occurred on conjugation to complexes 3 or 4. The nanoprobes were selectively screened in the presence of different cations and Hg2+ showed excellent affinity in “turning ON” the fluorescence of the nanoprobes. Experimental results showed that the sensitivity of QDs-4 towards Hg2+ was much higher than that of QDs-3 nanoprobe. The mechanism of reaction has been elucidated based on the ability of Hg2+ to coordinate with the sulphur atom of the Ni complex ring and apparently “turn ON” the fluorescence of the linked QDs.
- Full Text:
- Date Issued: 2014
Urban agriculture for sustainable livelihood : a case study of migrants' women in Johannesburg
- Authors: Agho, Njenyuei Gideon
- Date: 2014
- Subjects: Urban agriculture -- Economic aspects -- South Africa -- Johannesburg , Agriculture -- Economic aspects -- South Africa , Rural-urban migration -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9228 , http://hdl.handle.net/10948/d1020980
- Description: This research examines how urban agriculture contributes to the sustainable livelihood of migrants’ women living in the inner city of Johannesburg. The study focuses on the Cameroonian women community living in Turffontein. It explores the significant process of migration into the Republic of South Africa and the inspiration behind the choice of urban agriculture in the inner city of Johannesburg by women. The research report assesses the impact of urban agriculture on sustainable livelihood in the life of Cameroonian women living in Turffontein. It also examines the constraints encountered by these Cameroonians women in Turffontein in the practice of urban agriculture for sustainable livelihood. The findings of this study reveal that urban agriculture is used as a strategy for sustainable livelihood to a lot of Cameroonian migrants’ women living in Turffontein. The study has also shown how through urban agriculture these migrants’ women have been able to raise substantial income to support their respective families both in South Africa and in Cameroon. The study is based on a purposeful sample of Cameroonian migrants’ women living in the inner city of Johannesburg practicing urban agriculture. It uses a mixed method of approach with a transect walk to the area where this women practice the urban agriculture. It also included an in-depth face to face interactive interview and written sources such as journals, books and research reports where combined to gather relevant data. Thematic content analysis was used to analyse the data.
- Full Text:
- Date Issued: 2014
- Authors: Agho, Njenyuei Gideon
- Date: 2014
- Subjects: Urban agriculture -- Economic aspects -- South Africa -- Johannesburg , Agriculture -- Economic aspects -- South Africa , Rural-urban migration -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9228 , http://hdl.handle.net/10948/d1020980
- Description: This research examines how urban agriculture contributes to the sustainable livelihood of migrants’ women living in the inner city of Johannesburg. The study focuses on the Cameroonian women community living in Turffontein. It explores the significant process of migration into the Republic of South Africa and the inspiration behind the choice of urban agriculture in the inner city of Johannesburg by women. The research report assesses the impact of urban agriculture on sustainable livelihood in the life of Cameroonian women living in Turffontein. It also examines the constraints encountered by these Cameroonians women in Turffontein in the practice of urban agriculture for sustainable livelihood. The findings of this study reveal that urban agriculture is used as a strategy for sustainable livelihood to a lot of Cameroonian migrants’ women living in Turffontein. The study has also shown how through urban agriculture these migrants’ women have been able to raise substantial income to support their respective families both in South Africa and in Cameroon. The study is based on a purposeful sample of Cameroonian migrants’ women living in the inner city of Johannesburg practicing urban agriculture. It uses a mixed method of approach with a transect walk to the area where this women practice the urban agriculture. It also included an in-depth face to face interactive interview and written sources such as journals, books and research reports where combined to gather relevant data. Thematic content analysis was used to analyse the data.
- Full Text:
- Date Issued: 2014
Usage of tribal assets towards community development : case study Royal Bafokeng Nation
- Authors: Mosarwa, Ipeleng Felicia
- Date: 2014
- Subjects: Rural development -- South Africa -- North-West , Sustainable living -- South Africa -- North-West
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9194 , http://hdl.handle.net/10948/d1020378
- Description: Tribal (rural) communities possess assets/resources that can be utilised in improving the quality of life of their residents. The processes involved in the usage of these assets toward community-led development can determine the success or failure of the development efforts by the community. The research conducted was aimed at investigating the processes involved in utilising these assets, with reference being placed on two community-led development approaches namely Asset Based Community Development and Sustainable Livelihood Framework. The research will examine the processes that the Royal Bafokeng Nation has used in the successful development of its community. A comparison of the community-led development processes will be compared to the Integrated Sustainable Development Strategy formulated by the South African government to develop rural communities. The results indicate that development is not just about asset identification, it‟s more complex than that. If development was just about resource identification then a lot of tribal communities would be developed. Development is about the interactions between leaders, community and external sources and in the case of RBN, administration as well. It is about interaction between leaders and community in the form of participation in development efforts; interaction between leaders (and administration) with external sources such as municipalities to enhance development; and interaction between community and external sources through social capital. The results also indicate that whilst it is the duty of government to provide basic services, communities can partake in other development initiatives. That development in it‟s entirely should not be left to government if communities have the means of initiating development. That government has to improve certain aspects in their development strategies, but that it has made strides in formulating strategies to develop rural communities. The challenges for government come in the implementation of these strategies. That partnership between community and government can lead to better and sustainable development initiatives.
- Full Text:
- Date Issued: 2014
- Authors: Mosarwa, Ipeleng Felicia
- Date: 2014
- Subjects: Rural development -- South Africa -- North-West , Sustainable living -- South Africa -- North-West
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9194 , http://hdl.handle.net/10948/d1020378
- Description: Tribal (rural) communities possess assets/resources that can be utilised in improving the quality of life of their residents. The processes involved in the usage of these assets toward community-led development can determine the success or failure of the development efforts by the community. The research conducted was aimed at investigating the processes involved in utilising these assets, with reference being placed on two community-led development approaches namely Asset Based Community Development and Sustainable Livelihood Framework. The research will examine the processes that the Royal Bafokeng Nation has used in the successful development of its community. A comparison of the community-led development processes will be compared to the Integrated Sustainable Development Strategy formulated by the South African government to develop rural communities. The results indicate that development is not just about asset identification, it‟s more complex than that. If development was just about resource identification then a lot of tribal communities would be developed. Development is about the interactions between leaders, community and external sources and in the case of RBN, administration as well. It is about interaction between leaders and community in the form of participation in development efforts; interaction between leaders (and administration) with external sources such as municipalities to enhance development; and interaction between community and external sources through social capital. The results also indicate that whilst it is the duty of government to provide basic services, communities can partake in other development initiatives. That development in it‟s entirely should not be left to government if communities have the means of initiating development. That government has to improve certain aspects in their development strategies, but that it has made strides in formulating strategies to develop rural communities. The challenges for government come in the implementation of these strategies. That partnership between community and government can lead to better and sustainable development initiatives.
- Full Text:
- Date Issued: 2014