Chemical constituents and biological studies of Tagetes minuta L. and Rauvolfia caffra Sond
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
- Authors: Mlala, Sithenkosi
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Organic Chemistry)
- Identifier: vital:11358 , http://hdl.handle.net/10353/d1021325
- Description: Consequently, specific parts or the whole plant can be used for various treatments. The aim of this study was to extract, isolate and characterize the biologically active volatile and non-volatile compounds from Tagetes minuta and Rauvolfia caffra respectively. Tagetes minuta plant was considered for extraction of essential oils using hydrodistillation method. Cis-β-ocimene (38.03%), caryophyllene oxide (18.04%), alloocimene (25.35 %), isopropyl tetradecanoate (17.02 %), cis-ocimene (38.14%) and trans-β-ocimene (37.03%) were the major components of essential oil analyzed from fresh stem, dried stem, fresh leaf, dried leaf, fresh flower and dried flower respectively. The volatile compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography (GC). Essential oil of dried stem leaf and flower parts of T. minuta exhibit antioxidant activity as demonstrated by the DPPH and FRAP bioassays. Crude extracts were extracted from R. caffra stem bark using sequence of solvents namely n-hexane, dichloromethane, ethyl acetate, methanol and ethanol. A white powder, a β-sitosterol (non-volatile compound) was isolated by column chromatography from ethyl acetate fractions of R. caffra stem bark and identified on various spectroscopic techniques such as FTIR and (1D and 2D) NMR. Melting point was also determined to be a sharp 129-130 ºC. DCM, EA, MetOH and EtOH fractions as well as β-Sitosterol (compound SM/01), showed antioxidant activity when tested on DPPH, FRAP, total phenolic and flavonoid bioassays. This antioxidant activity might be due to the presence of hydroxyl groups in the compound and crude fractions. On the other hand, T. minuta’s essential oil showed high antioxidant activity when evaluated on the DPPH and FRAP bioassays, which can be attributed to the presence of oxygenated monoterpenes and sesquiterpenes known to act as free radical scavenging and reducing agents. The use of R. caffra stem bark extracts against hypertension and other diseases by traditional healers could be attributed to the presence of phytochemicals (polyphenols and flavonoids) with known health benefits. Thus, it is recommended that the plant should be exploited further using modern techniques involving separation and purification of compounds that can be used for drug formulation. This study supports the use of T. minuta and R. caffra as the potential natural antioxidant source to manage various diseases including hypertension.
- Full Text:
- Date Issued: 2015
CHIP: a co-chaperone for degradation by the proteasome
- Authors: Edkins, Adrienne L
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/164863 , vital:41179 , ISBN 978-3-319-11730-0 , DOI: 10.1007/978-3-319-11731-7_11
- Description: Protein homeostasis relies on a balance between protein folding and protein degradation. Molecular chaperones like Hsp70 and Hsp90 fulfil well-defined roles in protein folding and conformational stability via ATP dependent reaction cycles. These folding cycles are controlled by associations with a cohort of non-client protein co-chaperones, such as Hop, p23 and Aha1. Pro-folding co-chaperones facilitate the transit of the client protein through the chaperone mediated folding process. However, chaperones are also involved in ubiquitin-mediated proteasomal degradation of client proteins. Similar to folding complexes, the ability of chaperones to mediate protein degradation is regulated by co-chaperones, such as the C terminal Hsp70 binding protein (CHIP).
- Full Text:
- Date Issued: 2015
- Authors: Edkins, Adrienne L
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/164863 , vital:41179 , ISBN 978-3-319-11730-0 , DOI: 10.1007/978-3-319-11731-7_11
- Description: Protein homeostasis relies on a balance between protein folding and protein degradation. Molecular chaperones like Hsp70 and Hsp90 fulfil well-defined roles in protein folding and conformational stability via ATP dependent reaction cycles. These folding cycles are controlled by associations with a cohort of non-client protein co-chaperones, such as Hop, p23 and Aha1. Pro-folding co-chaperones facilitate the transit of the client protein through the chaperone mediated folding process. However, chaperones are also involved in ubiquitin-mediated proteasomal degradation of client proteins. Similar to folding complexes, the ability of chaperones to mediate protein degradation is regulated by co-chaperones, such as the C terminal Hsp70 binding protein (CHIP).
- Full Text:
- Date Issued: 2015
Classification System for Wetlands and Other Aquatic Ecosystems in South Africa:
- Authors: Ellery, William F N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144454 , vital:38347 , https://doi.org/10.2989/10220119.2015.1025843
- Description: There have been several attempts to develop a wetland classification for South Africa, with merit in each, but a system that satisfies the needs of a wide range of professionals has been elusive. This is partly to be expected since classification systems are often user-specific. Nevertheless, and at last, the authors of Classification System for Wetlands and Other Aquatic Ecosystems in South Africa. User Manual: Inland Systems (SANBI Biodiversity Series 22) have developed a robust and comprehensive wetland classification system for South Africa that likely will have broad appeal and be widely used. Working for Wetlands, the Water Research Commission (WRC) and SANBI provided considerable support for the development of this system and there was expert input from a wide range of stakeholders.
- Full Text:
- Date Issued: 2015
- Authors: Ellery, William F N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144454 , vital:38347 , https://doi.org/10.2989/10220119.2015.1025843
- Description: There have been several attempts to develop a wetland classification for South Africa, with merit in each, but a system that satisfies the needs of a wide range of professionals has been elusive. This is partly to be expected since classification systems are often user-specific. Nevertheless, and at last, the authors of Classification System for Wetlands and Other Aquatic Ecosystems in South Africa. User Manual: Inland Systems (SANBI Biodiversity Series 22) have developed a robust and comprehensive wetland classification system for South Africa that likely will have broad appeal and be widely used. Working for Wetlands, the Water Research Commission (WRC) and SANBI provided considerable support for the development of this system and there was expert input from a wide range of stakeholders.
- Full Text:
- Date Issued: 2015
Closed-loop temperature control of friction stir welding
- Authors: Pothier, Raymond Peter
- Date: 2015
- Subjects: Friction welding
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: http://hdl.handle.net/10948/10362 , vital:26656
- Description: This study develops and presents a friction stir weld (FSW) quality assurance tool based on control of weld zone temperature. Apart from correct tool geometry, tool tilt angle, traverse speed and forge force during welding, one important requirement is that the weld material be sufficiently plasticised (softened). The level of plasticisation is related to weld zone temperature which is primarily dependent on spindle speed, traverse speed and forge force. When all other conditions are correct, sufficiently plasticised material flows around and consolidates behind the tool without the production of voids in the weld. Typically, weld temperature varies along the weld length which may result in variations in weld quality. Weld zone temperature control makes constant weld zone temperature possible. In this study, thermocouple sensors were embedded in the FSW tool and a weld zone temperature control algorithm was developed. Spindle speed was the actuating mechanism for controlling weld temperature. The system was modelled and controllers were designed using Matlab tools. The system was simulated and the performance was compared to the system performance during welding. The control system ensures that the weld zone temperature can be maintained irrespective of the presence of thermal disturbances. Tensile testing was conducted which confirmed a range of temperature in which the welds resulted in consistent strength.
- Full Text:
- Date Issued: 2015
- Authors: Pothier, Raymond Peter
- Date: 2015
- Subjects: Friction welding
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: http://hdl.handle.net/10948/10362 , vital:26656
- Description: This study develops and presents a friction stir weld (FSW) quality assurance tool based on control of weld zone temperature. Apart from correct tool geometry, tool tilt angle, traverse speed and forge force during welding, one important requirement is that the weld material be sufficiently plasticised (softened). The level of plasticisation is related to weld zone temperature which is primarily dependent on spindle speed, traverse speed and forge force. When all other conditions are correct, sufficiently plasticised material flows around and consolidates behind the tool without the production of voids in the weld. Typically, weld temperature varies along the weld length which may result in variations in weld quality. Weld zone temperature control makes constant weld zone temperature possible. In this study, thermocouple sensors were embedded in the FSW tool and a weld zone temperature control algorithm was developed. Spindle speed was the actuating mechanism for controlling weld temperature. The system was modelled and controllers were designed using Matlab tools. The system was simulated and the performance was compared to the system performance during welding. The control system ensures that the weld zone temperature can be maintained irrespective of the presence of thermal disturbances. Tensile testing was conducted which confirmed a range of temperature in which the welds resulted in consistent strength.
- Full Text:
- Date Issued: 2015
Co-mapping the maze: a complex systems view of human trafficking in the Eastern Cape
- Authors: Van der Westhuizen, Amanda
- Date: 2015
- Subjects: Human trafficking -- South Africa -- Eastern Cape Forced labor -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/23305 , vital:30523
- Description: Researchers have described human trafficking as a complex, multi-layered crime. South Africa, including the Eastern Cape Province, is a source, transit, and destination country for trafficked people. However, a dearth of research on human trafficking exists in the province. Furthermore, traditional, modernist research using reductionist methods to investigate complex phenomena has proven unable to capture the complex interrelationships between the myriad of interrelated elements inherent in complex phenomena. In this qualitative study, I explore and describe the human trafficking system in the Eastern Cape via participants’ perspectives through a complex systems approach that consists of two complementary theories, namely Bronfenbrenner’s bioecological theory of human development and complexity theory. The participants, who were knowledgeable about human trafficking in the province, were obtained through purposive and snowball sampling. Data collection took place through open-ended interviews with individual participants. I analysed the data according to Miles and Huberman’s data analysis process and Braun and Clarke’s thematic data analysis process. The findings demonstrate that the complex systems approach successfully facilitated the mapping and conceptualisation of an in-depth, multi-level picture of the complex interrelationships within and between multiple system components in the human trafficking system and its environment in relation to the Eastern Cape Province. Participants’ perspectives revealed two main themes, namely, the prominence of the nonlinear interactions between traffickers and trafficked persons in the holistic human trafficking system and the major obstacle regarding the lack of witness credibility for human trafficking prosecutions to be successful. Utilising complex systems theory to conduct further human trafficking research could assist counter-trafficking stakeholders with an alternative approach to generating effective planning and executing counter human trafficking strategies in a rapidly changing and increasing complex interconnected world.
- Full Text:
- Date Issued: 2015
- Authors: Van der Westhuizen, Amanda
- Date: 2015
- Subjects: Human trafficking -- South Africa -- Eastern Cape Forced labor -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/23305 , vital:30523
- Description: Researchers have described human trafficking as a complex, multi-layered crime. South Africa, including the Eastern Cape Province, is a source, transit, and destination country for trafficked people. However, a dearth of research on human trafficking exists in the province. Furthermore, traditional, modernist research using reductionist methods to investigate complex phenomena has proven unable to capture the complex interrelationships between the myriad of interrelated elements inherent in complex phenomena. In this qualitative study, I explore and describe the human trafficking system in the Eastern Cape via participants’ perspectives through a complex systems approach that consists of two complementary theories, namely Bronfenbrenner’s bioecological theory of human development and complexity theory. The participants, who were knowledgeable about human trafficking in the province, were obtained through purposive and snowball sampling. Data collection took place through open-ended interviews with individual participants. I analysed the data according to Miles and Huberman’s data analysis process and Braun and Clarke’s thematic data analysis process. The findings demonstrate that the complex systems approach successfully facilitated the mapping and conceptualisation of an in-depth, multi-level picture of the complex interrelationships within and between multiple system components in the human trafficking system and its environment in relation to the Eastern Cape Province. Participants’ perspectives revealed two main themes, namely, the prominence of the nonlinear interactions between traffickers and trafficked persons in the holistic human trafficking system and the major obstacle regarding the lack of witness credibility for human trafficking prosecutions to be successful. Utilising complex systems theory to conduct further human trafficking research could assist counter-trafficking stakeholders with an alternative approach to generating effective planning and executing counter human trafficking strategies in a rapidly changing and increasing complex interconnected world.
- Full Text:
- Date Issued: 2015
Coastal landscape change on the Cape St Francis/St Francis Bay peninsula from 1960 to 2014
- Authors: Schroeder, Daniel Heiko
- Date: 2015
- Subjects: Coast changes -- South Africa -- Saint Francis, Cape , Peninsulas -- South Africa -- Saint Francis, Cape , Human ecology -- South Africa -- Saint Francis, Cape , Geographic information systems -- South Africa -- Saint Francis, Cape , Surveying -- South Africa -- Saint Francis, Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5086 , http://hdl.handle.net/10962/d1018203
- Description: A large proportion of the human population, their settlements and socioeconomic activities occur on land directly adjacent to the coastline. The increased demand for coastal leisure and tourism has interfered with natural landscape features and their associated processes. The Cape St Francis/St Francis Bay peninsula located on the southeast coast of South Africa was rapidly developed and transformed from a little fishing village into an urban coastal developed area over a 50-year period (1961-2014). A system that once existed in a state of dynamic or non-equilibrium was interfered with through anthropogenic disturbances, resulting in more frequent and intense natural events, which ranged from floods to debris flows, decreased sand supply and resulting beach erosion. The aim of the project was to identify and map landscape features and changes on the peninsula using an interdisciplinary approach. The triangulated methods of a desktop study using Geographic Information Systems (GIS) and media reviews, a crowdsourcing/participatory approach based on interviews, and a one year land surveying period of measurable field based surveys of physical features gave a well balanced view. The research showed that the natural landscape has been altered dramatically by settlement and associated infrastructure development. In particular, the loss of dunefields and the artificial modification of river paths were major impact areas. Beach erosion is a continual issue for the peninsula residents, particularly in St Francis Bay.
- Full Text:
- Date Issued: 2015
- Authors: Schroeder, Daniel Heiko
- Date: 2015
- Subjects: Coast changes -- South Africa -- Saint Francis, Cape , Peninsulas -- South Africa -- Saint Francis, Cape , Human ecology -- South Africa -- Saint Francis, Cape , Geographic information systems -- South Africa -- Saint Francis, Cape , Surveying -- South Africa -- Saint Francis, Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5086 , http://hdl.handle.net/10962/d1018203
- Description: A large proportion of the human population, their settlements and socioeconomic activities occur on land directly adjacent to the coastline. The increased demand for coastal leisure and tourism has interfered with natural landscape features and their associated processes. The Cape St Francis/St Francis Bay peninsula located on the southeast coast of South Africa was rapidly developed and transformed from a little fishing village into an urban coastal developed area over a 50-year period (1961-2014). A system that once existed in a state of dynamic or non-equilibrium was interfered with through anthropogenic disturbances, resulting in more frequent and intense natural events, which ranged from floods to debris flows, decreased sand supply and resulting beach erosion. The aim of the project was to identify and map landscape features and changes on the peninsula using an interdisciplinary approach. The triangulated methods of a desktop study using Geographic Information Systems (GIS) and media reviews, a crowdsourcing/participatory approach based on interviews, and a one year land surveying period of measurable field based surveys of physical features gave a well balanced view. The research showed that the natural landscape has been altered dramatically by settlement and associated infrastructure development. In particular, the loss of dunefields and the artificial modification of river paths were major impact areas. Beach erosion is a continual issue for the peninsula residents, particularly in St Francis Bay.
- Full Text:
- Date Issued: 2015
Community engagement in practice? : an exploration of the relationship between the University of Fort Hare (Alice Campus) and the Ilima Agripark Project
- Authors: Jubera, Memory
- Date: 2015
- Subjects: Community development--South Africa Universities and colleges--South Africa Sustainable development--South Africa
- Language: English
- Type: Thesis , Masters , Sociology
- Identifier: http://hdl.handle.net/10353/17327 , vital:40956
- Description: Cooperatives have principles and goals that regulate their day-to-day operations. Their aim is to create jobs through carrying out income generating projects. This aim is usually difficult to achieve as ‘human’ factors sometimes obscure the projects’ progress. This study therefore explored the nature of relationship that exists between the University of Fort Hare (UFH) and the cooperative members involved in the project, which in this study are referred to as, Ilima Agripark Project (IAP) members. This relationship was investigated through the three particular forms (information, consultation and participation) of community engagement, their nature, meanings, the influence they possess and how IAP/UFH members comprehend these. Guided by her research matrix and interview guide, the researcher used the qualitative and interpretive approach method to collect data. The case study made use of document analysis, key informant interviews, direct observations, face to face interviews and focus group discussions to collect data. In order to validate her data, she also made use of a tape recorder and notebook. The study’s key finding is that the three particular community engagement forms are not fully utilised by the university. The study revealed that there is lack of transparency when it comes to information dissemination hence, the IAP members feel insecure and socially excluded.
- Full Text:
- Date Issued: 2015
- Authors: Jubera, Memory
- Date: 2015
- Subjects: Community development--South Africa Universities and colleges--South Africa Sustainable development--South Africa
- Language: English
- Type: Thesis , Masters , Sociology
- Identifier: http://hdl.handle.net/10353/17327 , vital:40956
- Description: Cooperatives have principles and goals that regulate their day-to-day operations. Their aim is to create jobs through carrying out income generating projects. This aim is usually difficult to achieve as ‘human’ factors sometimes obscure the projects’ progress. This study therefore explored the nature of relationship that exists between the University of Fort Hare (UFH) and the cooperative members involved in the project, which in this study are referred to as, Ilima Agripark Project (IAP) members. This relationship was investigated through the three particular forms (information, consultation and participation) of community engagement, their nature, meanings, the influence they possess and how IAP/UFH members comprehend these. Guided by her research matrix and interview guide, the researcher used the qualitative and interpretive approach method to collect data. The case study made use of document analysis, key informant interviews, direct observations, face to face interviews and focus group discussions to collect data. In order to validate her data, she also made use of a tape recorder and notebook. The study’s key finding is that the three particular community engagement forms are not fully utilised by the university. The study revealed that there is lack of transparency when it comes to information dissemination hence, the IAP members feel insecure and socially excluded.
- Full Text:
- Date Issued: 2015
Comparative electrocatalytic studies of nanocomposites of mixed and covalently linked multiwalled carbon nanotubes and 4-(4, 6-diaminopyrimidin-2-ylthio) phthalocyaninato cobalt (II)
- Nyoni, Stephen, Nyokong, Tebello
- Authors: Nyoni, Stephen , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189285 , vital:44834 , xlink:href="https://doi.org/10.1016/j.poly.2015.05.038"
- Description: Electrocatalytic behavior of 4-(4,6-diaminopyrimidin-2-ylthio) phthalocyaninato cobalt(II) (CoPyPc) when mixed or covalently mixed to multiwalled carbon nanotubes (MWCNTs) is reported. Infra-red spectroscopy was used to confirm amide linkage of the covalently linked nanocomposite. Rotating disk electrode (RDE) and cyclic (CV) voltammetry studies were used for the electrochemical characterization of the prepared phthalocyanine and MWCNT nanocomposite. The electrocatalytic effects of the nanocomposites of the cobalt phthalocyanine derivative were then investigated towards L-cysteine oxidation using both RDE and CV experiments, and the electrocatalytic performance of the covalently linked cobalt phthalocyanine-MWCNT was found to be superior over the mixed nanocomposite.
- Full Text:
- Date Issued: 2015
- Authors: Nyoni, Stephen , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189285 , vital:44834 , xlink:href="https://doi.org/10.1016/j.poly.2015.05.038"
- Description: Electrocatalytic behavior of 4-(4,6-diaminopyrimidin-2-ylthio) phthalocyaninato cobalt(II) (CoPyPc) when mixed or covalently mixed to multiwalled carbon nanotubes (MWCNTs) is reported. Infra-red spectroscopy was used to confirm amide linkage of the covalently linked nanocomposite. Rotating disk electrode (RDE) and cyclic (CV) voltammetry studies were used for the electrochemical characterization of the prepared phthalocyanine and MWCNT nanocomposite. The electrocatalytic effects of the nanocomposites of the cobalt phthalocyanine derivative were then investigated towards L-cysteine oxidation using both RDE and CV experiments, and the electrocatalytic performance of the covalently linked cobalt phthalocyanine-MWCNT was found to be superior over the mixed nanocomposite.
- Full Text:
- Date Issued: 2015
Comparative photophysicochemical behavior of nanoconjugates of indium tetracarboxyphenoxy phthalocyanines covalently linked to CdTe/ZnSe/ZnO quantum dots
- Oluwole, David O, Nyokong, Tebello
- Authors: Oluwole, David O , Nyokong, Tebello
- Date: 2015
- Language: English
- Type: text , Article
- Identifier: vital:7294 , http://hdl.handle.net/10962/d1020357 , http://dx.doi.org/10.1016/j.jphotochem.2015.07.009
- Description: This work reports on the photophysicochemical behavior of different nanoconjugates of core/shell/shell (GSH-CdTe/ZnSe/ZnO), core/shell (GSH-CdTe/ZnSe) and core (GSH-CdTe) (quantum dots QDs) with indium tetracarboxyphenoxy phthalocyanines ((OH)InTCPPc) in dimethylsulfoxide. The fluorescence quantum yields (Φf) and lifetimes (τf, in brackets) of QDs ranged from 0.20 (13.9 ns) to 0.42 (25.6 ns). The highest Φf value was obtained for GSH-CdTe/ZnSe/ZnO (4.5) while the least was observed in GSH-CdTe/ZnSe/ZnO (7.6), the numbers in brackets refer to the sizes. For (OH)InTCPPc alone a Φf and τf values of 0.02 and 2.43 ns, respectively were obtained. In the nanoconjugates, pivotal decrease in the Φf and τf of the QDs were observed with increase in the triplet and singlet oxygen quantum yields of (OH)InTCPPc. , Original publication is available at http://dx.doi.org/10.1016/j.jphotochem.2015.07.009
- Full Text: false
- Date Issued: 2015
- Authors: Oluwole, David O , Nyokong, Tebello
- Date: 2015
- Language: English
- Type: text , Article
- Identifier: vital:7294 , http://hdl.handle.net/10962/d1020357 , http://dx.doi.org/10.1016/j.jphotochem.2015.07.009
- Description: This work reports on the photophysicochemical behavior of different nanoconjugates of core/shell/shell (GSH-CdTe/ZnSe/ZnO), core/shell (GSH-CdTe/ZnSe) and core (GSH-CdTe) (quantum dots QDs) with indium tetracarboxyphenoxy phthalocyanines ((OH)InTCPPc) in dimethylsulfoxide. The fluorescence quantum yields (Φf) and lifetimes (τf, in brackets) of QDs ranged from 0.20 (13.9 ns) to 0.42 (25.6 ns). The highest Φf value was obtained for GSH-CdTe/ZnSe/ZnO (4.5) while the least was observed in GSH-CdTe/ZnSe/ZnO (7.6), the numbers in brackets refer to the sizes. For (OH)InTCPPc alone a Φf and τf values of 0.02 and 2.43 ns, respectively were obtained. In the nanoconjugates, pivotal decrease in the Φf and τf of the QDs were observed with increase in the triplet and singlet oxygen quantum yields of (OH)InTCPPc. , Original publication is available at http://dx.doi.org/10.1016/j.jphotochem.2015.07.009
- Full Text: false
- Date Issued: 2015
Comparative study of clan CA cysteine proteases: an insight into the protozoan parasites
- Authors: Moyo, Sipho Dugunye
- Date: 2015
- Subjects: Cysteine proteinases , Proteolytic enzymes , Protozoan diseases , Parasites , Protozoan diseases -- Chemotherapy , Bioinformatics , Plasmodium , Antiprotozoal agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4165 , http://hdl.handle.net/10962/d1020309
- Description: Protozoan infections such as Malaria, Leishmaniasis, Toxoplasmosis, Chaga’s disease and African trypanosomiasis caused by the Plasmodium, Leishmania, Toxoplasma and Trypanosoma genuses respectively; inflict a huge economic, health and social impact in endemic regions particularly tropical and sub-tropical regions. The combined infections are estimated at over a billion annually and approximately 1.1 million deaths annually. The global burden of the protozoan infections is worsened by the increased drug resistance, toxicity and the relatively high cost of treatment and prophylaxis. Therefore there has been a high demand for new drugs and drug targets that play a role in parasite virulence. Cysteine proteases have been validated as viable drug targets due to their role in the infectivity stage of the parasites within the human host. There is a variety of cysteine proteases hence they are subdivided into families and in this study we focus on the clan CA, papain family C1 proteases. The current inhibitors for the protozoan cysteine proteases lack selectivity and specificity which contributes to drug toxicity. Therefore there is a need to identify the differences and similarities between the host, vector and protozoan proteases. This study uses a variety of bioinformatics tools to assess these differences and similarities. The Plasmodium cysteine protease FP-2 is the most characterized protease hence it was used as a reference to all the other proteases and its homologs were retrieved, aligned and the evolutionary relationships established. The homologs were also analysed for common motifs and the physicochemical properties determined which were validated using the Kruskal-Wallis test. These analyses revealed that the host and vector cathepsins share similar properties while the parasite cathepsins differ. At sub-site level sub-site 2 showed greater variations suggesting diverse ligand specificity within the proteases, a revelation that is vital in the design of antiprotozoan inhibitors.
- Full Text:
- Date Issued: 2015
- Authors: Moyo, Sipho Dugunye
- Date: 2015
- Subjects: Cysteine proteinases , Proteolytic enzymes , Protozoan diseases , Parasites , Protozoan diseases -- Chemotherapy , Bioinformatics , Plasmodium , Antiprotozoal agents
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4165 , http://hdl.handle.net/10962/d1020309
- Description: Protozoan infections such as Malaria, Leishmaniasis, Toxoplasmosis, Chaga’s disease and African trypanosomiasis caused by the Plasmodium, Leishmania, Toxoplasma and Trypanosoma genuses respectively; inflict a huge economic, health and social impact in endemic regions particularly tropical and sub-tropical regions. The combined infections are estimated at over a billion annually and approximately 1.1 million deaths annually. The global burden of the protozoan infections is worsened by the increased drug resistance, toxicity and the relatively high cost of treatment and prophylaxis. Therefore there has been a high demand for new drugs and drug targets that play a role in parasite virulence. Cysteine proteases have been validated as viable drug targets due to their role in the infectivity stage of the parasites within the human host. There is a variety of cysteine proteases hence they are subdivided into families and in this study we focus on the clan CA, papain family C1 proteases. The current inhibitors for the protozoan cysteine proteases lack selectivity and specificity which contributes to drug toxicity. Therefore there is a need to identify the differences and similarities between the host, vector and protozoan proteases. This study uses a variety of bioinformatics tools to assess these differences and similarities. The Plasmodium cysteine protease FP-2 is the most characterized protease hence it was used as a reference to all the other proteases and its homologs were retrieved, aligned and the evolutionary relationships established. The homologs were also analysed for common motifs and the physicochemical properties determined which were validated using the Kruskal-Wallis test. These analyses revealed that the host and vector cathepsins share similar properties while the parasite cathepsins differ. At sub-site level sub-site 2 showed greater variations suggesting diverse ligand specificity within the proteases, a revelation that is vital in the design of antiprotozoan inhibitors.
- Full Text:
- Date Issued: 2015
Comparative study of the effect of silver nanoparticles on the hexokinase activity from human and Trypanosoma brucei
- Authors: Mlozen, Madalitso Martin
- Date: 2015
- Subjects: Nanoparticles , Silver , Glucokinase , Trypanosoma brucei , Drug resistance , African trypanosomiasis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4149 , http://hdl.handle.net/10962/d1017910
- Full Text:
- Date Issued: 2015
- Authors: Mlozen, Madalitso Martin
- Date: 2015
- Subjects: Nanoparticles , Silver , Glucokinase , Trypanosoma brucei , Drug resistance , African trypanosomiasis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4149 , http://hdl.handle.net/10962/d1017910
- Full Text:
- Date Issued: 2015
Comparison between Endothelin, Nitric Oxide and their Association to Blood Pressure and Body Composition in HIV Patients, in Mthatha
- Authors: Zono, Sinethemba
- Date: 2015
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/2909 , vital:43105
- Description: Background: Dysfunction of the vascular endothelium is an early finding in the progression of cardiovascular disease and is closely related to clinical events in patients with obesity and hypertension. Vascular function is mediated by nitric oxide (NO) and endothelin (ET-1) which serve as natural counterparts. The aim of the study was to determine the physiological effects of HIV infection, blood pressure and body composition on the changes of ET-1 and NO and association between ET-1 and NO. Methods and results: This was a descriptive and comparative study. A Quota sample method was used. The study population consisted of 154 participants categorized into the following groups: 57 HIV negative participants (A), 40 HIV positive not on treatment participants and 57 HIV positive on treatment participants. Enzyme immunoassay kit was used for the quantitative determination of ET-1 and Nitrate/nitrite colorimetric assay kit was used for the determination of NO. Anthropometric measurements, body composition were determined. Hemodynamic measurements were also taken into account. Results: Resting metabolism, waist circumference (WC) and hip circumference had low mean levels in both HIV positives groups compared to HIV negative group. On lipid profiles visceral fat (VF), whole fat (WF) had low mean levels but skeletal muscle fat (SMF) showed the highest mean levels in both HIV positive groups. All the blood pressures between HIV groups were on a normal range scale. Mean values of endothelin and nitric oxide are increased in HIV positive not on ART and HIV (+) on ART compared with the HIV negative group. Conclusion: NO, ET-1, ART and HIV itself were associated with the pathogenesis of endothelial dysfunction in persons with HIV infection. Elevated endothelial markers namely ET-1 and NO can lead to improvement of endothelium dependent relaxation to some extent but not completely. Although these markers have deleterious effect on the endothelium but can also serve as up-regulator of hypertension. Key words: HIV-infection, antiretroviral therapy, endothelial dysfunction, Endothelin1 (ET-1), nitric oxide (NO), blood pressures (BPs). , Thesis (MSc) -- Faculty of Health Sciences, 2015
- Full Text:
- Date Issued: 2015
- Authors: Zono, Sinethemba
- Date: 2015
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/2909 , vital:43105
- Description: Background: Dysfunction of the vascular endothelium is an early finding in the progression of cardiovascular disease and is closely related to clinical events in patients with obesity and hypertension. Vascular function is mediated by nitric oxide (NO) and endothelin (ET-1) which serve as natural counterparts. The aim of the study was to determine the physiological effects of HIV infection, blood pressure and body composition on the changes of ET-1 and NO and association between ET-1 and NO. Methods and results: This was a descriptive and comparative study. A Quota sample method was used. The study population consisted of 154 participants categorized into the following groups: 57 HIV negative participants (A), 40 HIV positive not on treatment participants and 57 HIV positive on treatment participants. Enzyme immunoassay kit was used for the quantitative determination of ET-1 and Nitrate/nitrite colorimetric assay kit was used for the determination of NO. Anthropometric measurements, body composition were determined. Hemodynamic measurements were also taken into account. Results: Resting metabolism, waist circumference (WC) and hip circumference had low mean levels in both HIV positives groups compared to HIV negative group. On lipid profiles visceral fat (VF), whole fat (WF) had low mean levels but skeletal muscle fat (SMF) showed the highest mean levels in both HIV positive groups. All the blood pressures between HIV groups were on a normal range scale. Mean values of endothelin and nitric oxide are increased in HIV positive not on ART and HIV (+) on ART compared with the HIV negative group. Conclusion: NO, ET-1, ART and HIV itself were associated with the pathogenesis of endothelial dysfunction in persons with HIV infection. Elevated endothelial markers namely ET-1 and NO can lead to improvement of endothelium dependent relaxation to some extent but not completely. Although these markers have deleterious effect on the endothelium but can also serve as up-regulator of hypertension. Key words: HIV-infection, antiretroviral therapy, endothelial dysfunction, Endothelin1 (ET-1), nitric oxide (NO), blood pressures (BPs). , Thesis (MSc) -- Faculty of Health Sciences, 2015
- Full Text:
- Date Issued: 2015
Comparison of protein binding microarray derived and ChIP-seq derived transcription factor binding DNA motifs
- Hlatshwayo, Nkosikhona Rejoyce
- Authors: Hlatshwayo, Nkosikhona Rejoyce
- Date: 2015
- Subjects: Protein binding , DNA , DNA microarrays , Transcription factors , DNA-protein interactions , Gene regulatory networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4146 , http://hdl.handle.net/10962/d1017907
- Description: Transcription factors (TFs) are biologically important proteins that interact with transcription machinery and bind DNA regulatory sequences to regulate gene expression by modulating the synthesis of the messenger RNA. The regulatory sequences comprise of short conserved regions of a specific length called motifs . TFs have very diverse roles in different cells and play a very significant role in development. TFs have been associated with carcinogenesis in various tissue types, as well as developmental and hormone response disorders. They may be responsible for the regulation of oncogenes and can be oncogenic. Consequently, understanding TF binding and knowing the motifs to which they bind is worthy of attention and research focus. Various projects have made the study of TF binding their main focus; nevertheless, much about TF binding remains confounding. Chromatin immunoprecipitation in conjunction with deep sequencing (ChIP-seq) techniques are a popular method used to investigate DNA-TF interactions in vivo. This procedure is followed by motif discovery and motif enrichment analysis using relevant tools. Protein Binding Microarrays (PBMs) are an in vitro method for investigating DNA-TF interactions. We use a motif enrichment analysis tools (CentriMo and AME) and an empirical quality assessment tool (Area under the ROC curve) to investigate which method yields motifs that are a true representation of in vivo binding. Motif enrichment analysis: On average, ChIP-seq derived motifs from the JASPAR Core database outperformed PBM derived ones from the UniPROBE mouse database. However, the performance of motifs derived using these two methods is not much different from each other when using CentriMo and AME. The E-values from Motif enrichment analysis were not too different from each other or 0. CentriMo showed that in 35 cases JASPAR Core ChIP-seq derived motifs outperformed UniPROBE mouse PBM derived motifs, while it was only in 11 cases that PBM derived motifs outperformed ChIP-seq derived motifs. AME showed that in 18 cases JASPAR Core ChIP-seq derived motifs did better, while only it was only in 3 cases that UniPROBE motifs outperformed ChIP-seq derived motifs. We could not distinguish the performance in 25 cases. Empirical quality assessment: Area under the ROC curve values computations followed by a two-sided t-test showed that there is no significant difference in the average performances of the motifs from the two databases (with 95% confidence, mean of differences=0.0088125 p-value= 0.4874, DF=47) .
- Full Text:
- Date Issued: 2015
- Authors: Hlatshwayo, Nkosikhona Rejoyce
- Date: 2015
- Subjects: Protein binding , DNA , DNA microarrays , Transcription factors , DNA-protein interactions , Gene regulatory networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4146 , http://hdl.handle.net/10962/d1017907
- Description: Transcription factors (TFs) are biologically important proteins that interact with transcription machinery and bind DNA regulatory sequences to regulate gene expression by modulating the synthesis of the messenger RNA. The regulatory sequences comprise of short conserved regions of a specific length called motifs . TFs have very diverse roles in different cells and play a very significant role in development. TFs have been associated with carcinogenesis in various tissue types, as well as developmental and hormone response disorders. They may be responsible for the regulation of oncogenes and can be oncogenic. Consequently, understanding TF binding and knowing the motifs to which they bind is worthy of attention and research focus. Various projects have made the study of TF binding their main focus; nevertheless, much about TF binding remains confounding. Chromatin immunoprecipitation in conjunction with deep sequencing (ChIP-seq) techniques are a popular method used to investigate DNA-TF interactions in vivo. This procedure is followed by motif discovery and motif enrichment analysis using relevant tools. Protein Binding Microarrays (PBMs) are an in vitro method for investigating DNA-TF interactions. We use a motif enrichment analysis tools (CentriMo and AME) and an empirical quality assessment tool (Area under the ROC curve) to investigate which method yields motifs that are a true representation of in vivo binding. Motif enrichment analysis: On average, ChIP-seq derived motifs from the JASPAR Core database outperformed PBM derived ones from the UniPROBE mouse database. However, the performance of motifs derived using these two methods is not much different from each other when using CentriMo and AME. The E-values from Motif enrichment analysis were not too different from each other or 0. CentriMo showed that in 35 cases JASPAR Core ChIP-seq derived motifs outperformed UniPROBE mouse PBM derived motifs, while it was only in 11 cases that PBM derived motifs outperformed ChIP-seq derived motifs. AME showed that in 18 cases JASPAR Core ChIP-seq derived motifs did better, while only it was only in 3 cases that UniPROBE motifs outperformed ChIP-seq derived motifs. We could not distinguish the performance in 25 cases. Empirical quality assessment: Area under the ROC curve values computations followed by a two-sided t-test showed that there is no significant difference in the average performances of the motifs from the two databases (with 95% confidence, mean of differences=0.0088125 p-value= 0.4874, DF=47) .
- Full Text:
- Date Issued: 2015
Comparisons of isotopic niche widths of some invasive and indigenous fauna in a South African river
- Hill, Jaclyn M, Jones, Roy W, Hill, Martin P, Weyl, Olaf L F
- Authors: Hill, Jaclyn M , Jones, Roy W , Hill, Martin P , Weyl, Olaf L F
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423711 , vital:72088 , xlink:href="https://doi.org/10.1111/fwb.12542"
- Description: Biological invasions threaten ecosystem integrity and bio-diversity, with numerous adverse implications for native flora and fauna. Established populations of two notorious freshwater invaders, the snail Tarebia granifera and the fish Pterygoplichthys disjunctivus, have been reported on three continents and are frequently predicted to be in di-rect competition with native species for dietary resources.
- Full Text:
- Date Issued: 2015
- Authors: Hill, Jaclyn M , Jones, Roy W , Hill, Martin P , Weyl, Olaf L F
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423711 , vital:72088 , xlink:href="https://doi.org/10.1111/fwb.12542"
- Description: Biological invasions threaten ecosystem integrity and bio-diversity, with numerous adverse implications for native flora and fauna. Established populations of two notorious freshwater invaders, the snail Tarebia granifera and the fish Pterygoplichthys disjunctivus, have been reported on three continents and are frequently predicted to be in di-rect competition with native species for dietary resources.
- Full Text:
- Date Issued: 2015
Composition portfolio
- Richard, Paul Christian Patrice
- Authors: Richard, Paul Christian Patrice
- Date: 2015
- Subjects: Composition (Music) , Vocal music -- Scores
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2695 , http://hdl.handle.net/10962/d1017548
- Full Text:
- Date Issued: 2015
- Authors: Richard, Paul Christian Patrice
- Date: 2015
- Subjects: Composition (Music) , Vocal music -- Scores
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:2695 , http://hdl.handle.net/10962/d1017548
- Full Text:
- Date Issued: 2015
Conceptions of academics concerning the nature and purpose of teaching portfolios in higher education
- Authors: Champion, Eunice Nomava
- Date: 2015
- Subjects: Portfolios in education , Lecture method in teaching , College teaching , College teachers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9591 , http://hdl.handle.net/10948/d1021175
- Description: The purpose of this study was to explore the conceptions of academics at the NMMU concerning the nature and purpose of teaching portfolios in higher education. The study was guided by the following research question: What are the conceptions of academics concerning the nature and purpose of teaching portfolios in higher education? A case study, involving academics at the Nelson Mandela Metropolitan University (NMMU), was used to answer the research question. A sequential explanatory mixed-methods research design was employed to collect data from an electronic questionnaire consisting of Likert-scale type of responses and open-ended questions, followed by two focus group interviews with academics that had prior experience in the development of a teaching portfolio. Forty-five academics responded to the questionnaire sent to all the academics at the NMMU, providing a broad perspective on the conceptions of NMMU academics regarding the nature and purpose of teaching portfolios. The two focus group interviews were conducted with six and eight academics respectively who was purposively chosen for their prior experience with the development of teaching portfolios. The aim of the focus group interviews were to elaborate on the data generated by the questionnaire. The quantitative data gathered by the questionnaire was statistically analysed, generating descriptive statistics of the Likert type response statements. The transcripts of the focus group interviews were thematically analysed. The conceptual framework that initially guided the formulation of the sub-research questions was amended to include the themes that emerged from the thematic analysis of the data, namely: the portfolio development process, the uses of and purposes for developing teaching portfolios, the attitudes of academics towards teaching portfolios, and the benefits gained from the development of teaching portfolios. The findings of the study revealed that of the participants find work overload and additional responsibilities as major constraints and collaboration among peers as the most helpful factor in the development of a teaching portfolio. The findings further revealed that the majority of the participants identified items to be included in a teaching portfolio that would enable them to use the portfolio in the development of their teaching. A mixture of attitudes towards teaching portfolios was identified. Some academics (in particular those who have prior experience in the development of portfolios) displayed a positive attitude towards teaching portfolios, while participants reported a negative attitude towards teaching portfolios by most of their colleagues (mostly those who have not developed a portfolio yet). The negative attitudes do seem to overpower the positive attitudes towards teaching portfolios. The challenge to the NMMU would therefore be to get academics to make use of the initiatives provided by the NMMU to assist them with the teaching portfolio development process. Four recommendations that may serve as guidelines to assist in the successful implementation of teaching portfolios at the NMMU were made, based on the findings of the study. Although the results of this study cannot be generalized to other higher education institutions, they do provide insights in the conception of the academics regarding the nature and purpose of teaching portfolios at the NMMU that can be of benefit to other higher education institutions.
- Full Text:
- Date Issued: 2015
- Authors: Champion, Eunice Nomava
- Date: 2015
- Subjects: Portfolios in education , Lecture method in teaching , College teaching , College teachers
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:9591 , http://hdl.handle.net/10948/d1021175
- Description: The purpose of this study was to explore the conceptions of academics at the NMMU concerning the nature and purpose of teaching portfolios in higher education. The study was guided by the following research question: What are the conceptions of academics concerning the nature and purpose of teaching portfolios in higher education? A case study, involving academics at the Nelson Mandela Metropolitan University (NMMU), was used to answer the research question. A sequential explanatory mixed-methods research design was employed to collect data from an electronic questionnaire consisting of Likert-scale type of responses and open-ended questions, followed by two focus group interviews with academics that had prior experience in the development of a teaching portfolio. Forty-five academics responded to the questionnaire sent to all the academics at the NMMU, providing a broad perspective on the conceptions of NMMU academics regarding the nature and purpose of teaching portfolios. The two focus group interviews were conducted with six and eight academics respectively who was purposively chosen for their prior experience with the development of teaching portfolios. The aim of the focus group interviews were to elaborate on the data generated by the questionnaire. The quantitative data gathered by the questionnaire was statistically analysed, generating descriptive statistics of the Likert type response statements. The transcripts of the focus group interviews were thematically analysed. The conceptual framework that initially guided the formulation of the sub-research questions was amended to include the themes that emerged from the thematic analysis of the data, namely: the portfolio development process, the uses of and purposes for developing teaching portfolios, the attitudes of academics towards teaching portfolios, and the benefits gained from the development of teaching portfolios. The findings of the study revealed that of the participants find work overload and additional responsibilities as major constraints and collaboration among peers as the most helpful factor in the development of a teaching portfolio. The findings further revealed that the majority of the participants identified items to be included in a teaching portfolio that would enable them to use the portfolio in the development of their teaching. A mixture of attitudes towards teaching portfolios was identified. Some academics (in particular those who have prior experience in the development of portfolios) displayed a positive attitude towards teaching portfolios, while participants reported a negative attitude towards teaching portfolios by most of their colleagues (mostly those who have not developed a portfolio yet). The negative attitudes do seem to overpower the positive attitudes towards teaching portfolios. The challenge to the NMMU would therefore be to get academics to make use of the initiatives provided by the NMMU to assist them with the teaching portfolio development process. Four recommendations that may serve as guidelines to assist in the successful implementation of teaching portfolios at the NMMU were made, based on the findings of the study. Although the results of this study cannot be generalized to other higher education institutions, they do provide insights in the conception of the academics regarding the nature and purpose of teaching portfolios at the NMMU that can be of benefit to other higher education institutions.
- Full Text:
- Date Issued: 2015
Conditions enabling or constraining the exercise of agency among new academics in higher education, conducive to the social inclusion of students
- Authors: Behari-Leak, Kasturi
- Date: 2015
- Subjects: Social integration -- South Africa , Students -- South Africa -- Social conditions , Educational change -- South Africa , College teachers -- South Africa , Education, Higher -- South Africa , Critical realism , Social realism , Agent (Philosophy)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1333 , http://hdl.handle.net/10962/d1020295
- Description: This study, which is part of a National Research Foundation project on Social Inclusion in Higher Education (HE), focuses on the exercise of agency among new academics, conducive to the social inclusion of students. Transitioning from varied entry points into higher education, new academics face numerous challenges as they embed themselves in disciplinary and institutional contexts. Given the complexity and contested nature of the current higher education landscape, new academics are especially vulnerable. Using Roy Bhaskar’s critical realism as meta-theoretical framing and Margaret Archer’s social realist theory, with its methodological focus on analytical dualism and morphogenesis, this study offers a social realist account of how new academics engage with enabling and constraining conditions at institutional, faculty, departmental and classroom levels. Through an analysis of six individual narratives of mediation, this study explicates and exemplifies the range of agential choices exercised by new academics to mediate their contested spaces. A nuanced social and critical account of the material, ideational and agential conditions in HE shows that the courses of action taken by these new academics are driven through their concerns, commitments and projects in higher education. Yet, despite the university’s espousal of embracing change, the current induction and transition of new academics is inadequate to the task of transformation in higher education. Systemic conditions in HE, conducive to critical agency and social justice, are not enabling. Bhaskar’s Seven Scalar Being, used as an analytical frame and heuristic, guides the cross-case analysis of the six narratives across seven levels of ontology. The findings highlight that, despite difficult contextual influences, the positive exercise of agency is a marked feature of new participants in HE in this study. This has immediate implications for ways in which professional and academic development, and disciplinary and departmental programmes, could create and sustain conducive conditions for the professionalisation of new academics through more sensitised practices. Using alternative research methods such as photovoice to generate its data, this doctoral study proposes that new research methodologies, located in the third space, are needed now more than ever in HE sociological research, to recognise the researcher and the research participants as independent, autonomous and causally efficacious beings. To this end, this study includes a Chapter Zero, which captures the narrative of the doctoral scholar as researcher, who, shaped and influenced by established doctoral practices and traditions in the field, exercises her own doctoral agency in particular ways.
- Full Text:
- Date Issued: 2015
- Authors: Behari-Leak, Kasturi
- Date: 2015
- Subjects: Social integration -- South Africa , Students -- South Africa -- Social conditions , Educational change -- South Africa , College teachers -- South Africa , Education, Higher -- South Africa , Critical realism , Social realism , Agent (Philosophy)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1333 , http://hdl.handle.net/10962/d1020295
- Description: This study, which is part of a National Research Foundation project on Social Inclusion in Higher Education (HE), focuses on the exercise of agency among new academics, conducive to the social inclusion of students. Transitioning from varied entry points into higher education, new academics face numerous challenges as they embed themselves in disciplinary and institutional contexts. Given the complexity and contested nature of the current higher education landscape, new academics are especially vulnerable. Using Roy Bhaskar’s critical realism as meta-theoretical framing and Margaret Archer’s social realist theory, with its methodological focus on analytical dualism and morphogenesis, this study offers a social realist account of how new academics engage with enabling and constraining conditions at institutional, faculty, departmental and classroom levels. Through an analysis of six individual narratives of mediation, this study explicates and exemplifies the range of agential choices exercised by new academics to mediate their contested spaces. A nuanced social and critical account of the material, ideational and agential conditions in HE shows that the courses of action taken by these new academics are driven through their concerns, commitments and projects in higher education. Yet, despite the university’s espousal of embracing change, the current induction and transition of new academics is inadequate to the task of transformation in higher education. Systemic conditions in HE, conducive to critical agency and social justice, are not enabling. Bhaskar’s Seven Scalar Being, used as an analytical frame and heuristic, guides the cross-case analysis of the six narratives across seven levels of ontology. The findings highlight that, despite difficult contextual influences, the positive exercise of agency is a marked feature of new participants in HE in this study. This has immediate implications for ways in which professional and academic development, and disciplinary and departmental programmes, could create and sustain conducive conditions for the professionalisation of new academics through more sensitised practices. Using alternative research methods such as photovoice to generate its data, this doctoral study proposes that new research methodologies, located in the third space, are needed now more than ever in HE sociological research, to recognise the researcher and the research participants as independent, autonomous and causally efficacious beings. To this end, this study includes a Chapter Zero, which captures the narrative of the doctoral scholar as researcher, who, shaped and influenced by established doctoral practices and traditions in the field, exercises her own doctoral agency in particular ways.
- Full Text:
- Date Issued: 2015
Condoms in pockets and HIV-free certificates: mother-daughter communication about sex and risk in a time of AIDS epidemic in South Africa
- Authors: Wilbraham, Lindy
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143693 , vital:38274 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Responsive to the perceived high risks of sexual coercion, unwanted pregnancy and HIV-infection of girls in particular, several South African sexual health promotion campaigns have used media targeting parents (mothers in particular) to instruct them on how sex should be talked about with young people to ‘risk-proof’ them. Such an instrumentalist public health discourse posits this intergenerational communication as an ‘ongoing discussion’ of events, feelings, issues and risk-safe practices around heterosexual sex negotiation. A Foucauldian view finds these conversational imperatives pitched against much-talked-about resistances to talking about sex; and the saturation with risk of ambivalent mothers and silent daughters. Mother-daughter communication about sex and sexualities – as an uneasy western ideal of attachment parenting – has tangled roots in psychoanalytic theory and feminisms where sex as the core of modern subjectivity is normalized, capacities for intimacy are trained, and affiliative sexuality is modelled in ways that balance the rights and responsibilities of sexual agency/citizenship. This paper begins with two narrative fragments from a sexual health campaign that addressed mothers and daughters, and recounts how these ‘stories’ produced derisive laughter when introduced into group discussions with young/older women. The paper follows two lines of exploration. Firstly, is western idealized fabrication of inter-subjectivity between mothers and daughters desirable and feasible in post-apartheid conditions of epidemic in South Africa? And secondly, what if the narratives of lives and experiences we offer by way of health education materials provoke uncertainties, gaps and interrogations about sex, mothering and communication, instead of offering homilies and solutions?
- Full Text:
- Date Issued: 2015
- Authors: Wilbraham, Lindy
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143693 , vital:38274 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Responsive to the perceived high risks of sexual coercion, unwanted pregnancy and HIV-infection of girls in particular, several South African sexual health promotion campaigns have used media targeting parents (mothers in particular) to instruct them on how sex should be talked about with young people to ‘risk-proof’ them. Such an instrumentalist public health discourse posits this intergenerational communication as an ‘ongoing discussion’ of events, feelings, issues and risk-safe practices around heterosexual sex negotiation. A Foucauldian view finds these conversational imperatives pitched against much-talked-about resistances to talking about sex; and the saturation with risk of ambivalent mothers and silent daughters. Mother-daughter communication about sex and sexualities – as an uneasy western ideal of attachment parenting – has tangled roots in psychoanalytic theory and feminisms where sex as the core of modern subjectivity is normalized, capacities for intimacy are trained, and affiliative sexuality is modelled in ways that balance the rights and responsibilities of sexual agency/citizenship. This paper begins with two narrative fragments from a sexual health campaign that addressed mothers and daughters, and recounts how these ‘stories’ produced derisive laughter when introduced into group discussions with young/older women. The paper follows two lines of exploration. Firstly, is western idealized fabrication of inter-subjectivity between mothers and daughters desirable and feasible in post-apartheid conditions of epidemic in South Africa? And secondly, what if the narratives of lives and experiences we offer by way of health education materials provoke uncertainties, gaps and interrogations about sex, mothering and communication, instead of offering homilies and solutions?
- Full Text:
- Date Issued: 2015
Connectivity through allochthony: Reciprocal links between adjacent aquatic and terrestrial ecosystems in South Africa
- Richoux, Nicole B, Moyo, Sydney, Chari, Lenin D, Bergamino, Leandro, Carassou, Laure, Dalu, Tatenda, Hean, Jeffrey W, Sikutshwa, Likho, Gininda, Simphiwe, Magoro, Mandla L, Perhar, Gurbir, Ni, Felicity, Villet, Martin H, Whitfield, Alan K, Parker, Daniel M, Froneman, P William, Arhonditsis, George, Craig, Adrian J F K
- Authors: Richoux, Nicole B , Moyo, Sydney , Chari, Lenin D , Bergamino, Leandro , Carassou, Laure , Dalu, Tatenda , Hean, Jeffrey W , Sikutshwa, Likho , Gininda, Simphiwe , Magoro, Mandla L , Perhar, Gurbir , Ni, Felicity , Villet, Martin H , Whitfield, Alan K , Parker, Daniel M , Froneman, P William , Arhonditsis, George , Craig, Adrian J F K
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438363 , vital:73454 , ISBN 978-1-4312-0679-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2186-1-15.pdf
- Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to ex-plore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
- Full Text:
- Date Issued: 2015
- Authors: Richoux, Nicole B , Moyo, Sydney , Chari, Lenin D , Bergamino, Leandro , Carassou, Laure , Dalu, Tatenda , Hean, Jeffrey W , Sikutshwa, Likho , Gininda, Simphiwe , Magoro, Mandla L , Perhar, Gurbir , Ni, Felicity , Villet, Martin H , Whitfield, Alan K , Parker, Daniel M , Froneman, P William , Arhonditsis, George , Craig, Adrian J F K
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438363 , vital:73454 , ISBN 978-1-4312-0679-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2186-1-15.pdf
- Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to ex-plore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
- Full Text:
- Date Issued: 2015
Conscientious objection and South African medical practitioners' constructions of termination of pregnancy and emergency contraception
- Authors: Chiwandire, Desire
- Date: 2015
- Subjects: Abortion -- South Africa , Abortion -- Moral and ethical aspects -- South Africa , Emergency contraceptives -- South Africa , Contraception -- Moral and ethical aspects -- South Africa , Medical personnel -- Attitudes -- South Africa , Patients -- Legal status, laws, etc. -- South Africa , Reproductive rights -- South Africa , Women's rights -- South Africa , Liberty of conscience
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2888 , http://hdl.handle.net/10962/d1017863
- Description: Aim: The 1996 Choice on Termination of Pregnancy Act decriminalized abortion in South Africa and the South African Medicines Control Council in 2000 approved the dispensing of emergency contraceptive methods by pharmacists to women without a doctor's prescription. This legislation has been hailed as among the most progressive in the world with respect to women's reproductive justice. However the realisation of these rights in practice has not always met expectations in part due to medical practitioners' ethical objections to termination of pregnancy and the provision of related services. The aim of this study was to interpret the varying ways in which medical practitioners frame termination of pregnancy and emergency contraceptive services, their own professional identities and that of their patients/clients. Methods: Sample of 58 doctors and 59 pharmacists drawn from all nine provinces of South Africa. Data collected using an anonymous confidential internet-based self-administered questionnaire. Participants were randomly recruited from online listings of South African doctors and pharmacists practicing in both private and public sectors. Data were analysed using theoretically derived qualitative content analysis. Results: Participants drew on eight frames to justify their willingness or unwillingness to provide termination-of-pregnancy related services: the foetal life frame, the women's rights frame, the balancing frame, the social justice frame, the do no harm frame, the legal and professional obligation frame, the consequences frame and the moral absolutist frame. Conclusion: Health professionals' willingness or unwillingness to provide termination of pregnancy related services is highly dependent on how they frame or understand termination of pregnancy, and how they understand their own professional identities and those of their patients/clients.
- Full Text:
- Date Issued: 2015
- Authors: Chiwandire, Desire
- Date: 2015
- Subjects: Abortion -- South Africa , Abortion -- Moral and ethical aspects -- South Africa , Emergency contraceptives -- South Africa , Contraception -- Moral and ethical aspects -- South Africa , Medical personnel -- Attitudes -- South Africa , Patients -- Legal status, laws, etc. -- South Africa , Reproductive rights -- South Africa , Women's rights -- South Africa , Liberty of conscience
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2888 , http://hdl.handle.net/10962/d1017863
- Description: Aim: The 1996 Choice on Termination of Pregnancy Act decriminalized abortion in South Africa and the South African Medicines Control Council in 2000 approved the dispensing of emergency contraceptive methods by pharmacists to women without a doctor's prescription. This legislation has been hailed as among the most progressive in the world with respect to women's reproductive justice. However the realisation of these rights in practice has not always met expectations in part due to medical practitioners' ethical objections to termination of pregnancy and the provision of related services. The aim of this study was to interpret the varying ways in which medical practitioners frame termination of pregnancy and emergency contraceptive services, their own professional identities and that of their patients/clients. Methods: Sample of 58 doctors and 59 pharmacists drawn from all nine provinces of South Africa. Data collected using an anonymous confidential internet-based self-administered questionnaire. Participants were randomly recruited from online listings of South African doctors and pharmacists practicing in both private and public sectors. Data were analysed using theoretically derived qualitative content analysis. Results: Participants drew on eight frames to justify their willingness or unwillingness to provide termination-of-pregnancy related services: the foetal life frame, the women's rights frame, the balancing frame, the social justice frame, the do no harm frame, the legal and professional obligation frame, the consequences frame and the moral absolutist frame. Conclusion: Health professionals' willingness or unwillingness to provide termination of pregnancy related services is highly dependent on how they frame or understand termination of pregnancy, and how they understand their own professional identities and those of their patients/clients.
- Full Text:
- Date Issued: 2015