Investigation of molecular mechanism of recognition between citral and MARK4: A newer therapeutic approach to attenuate cancer cell progression
- Naz, Farha, Khan, Faez I, Mohammad, Taj, Khan, Parvez, Manzoor, Saaliqa, Hasan, Gulam M, Lobb, Kevin A, Luqman, Suaib, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Naz, Farha , Khan, Faez I , Mohammad, Taj , Khan, Parvez , Manzoor, Saaliqa , Hasan, Gulam M , Lobb, Kevin A , Luqman, Suaib , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447967 , vital:74687 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.10.143"
- Description: Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100 ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.
- Full Text:
- Date Issued: 2018
- Authors: Naz, Farha , Khan, Faez I , Mohammad, Taj , Khan, Parvez , Manzoor, Saaliqa , Hasan, Gulam M , Lobb, Kevin A , Luqman, Suaib , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447967 , vital:74687 , xlink:href="https://doi.org/10.1016/j.ijbiomac.2017.10.143"
- Description: Microtubule affinity regulating kinase 4 (MARK4) is a member of AMP-activated protein kinase, found to be involved in apoptosis, inflammation and many other regulatory pathways. Since, its aberrant expression is directly associated with the cell cycle and thus cancer. Therefore, MARK4 is being considered as a potential drug target for cancer therapy. Here, we investigated the mechanism of inhibition of MARK4 activity by citral. Docking studies suggested that citral effectively binds to the active site cavity, and complex is stabilized by several interactions. We further performed molecular dynamics simulation of MARK4-citral complex under explicit water condition for 100 ns and observed that binding of citral to MARK4 was quite stable. Fluorescence binding studies suggested that citral strongly binds to MARK4 and thereby inhibits its enzyme activity which was measured by the kinase inhibition assay. We further performed MTT assay and observed that citral inhibits proliferation of breast cancer cell line MCF-7. This work provides a newer insight into the use of citral as novel cancer therapeutics through the MARK4 inhibition. Results may be employed to design novel therapeutic molecule using citral as a scaffold for MARK4 inhibition to fight related diseases.
- Full Text:
- Date Issued: 2018
Identification and evaluation of bioactive natural products as potential inhibitors of human microtubule affinity-regulating kinase 4 (MARK4)
- Mohammad, Taj, Khan, Faez I, Lobb, Kevin A, Islam, Asimul, Ahmad, Faizan, Hassan, M Imtaiyaz
- Authors: Mohammad, Taj , Khan, Faez I , Lobb, Kevin A , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447159 , vital:74588 , xlink:href="https://doi.org/10.1080/07391102.2018.1468282"
- Description: Microtubule affinity-regulating kinase 4 (MARK4) has recently been identified as a potential drug target for several complex diseases including cancer, diabetes and neurodegenerative disorders. Inhibition of MARK4 activity is an appealing therapeutic option to treat such diseases. Here, we have performed structure-based virtual high-throughput screening of 100,000 naturally occurring compounds from ZINC database against MARK4 to find its potential inhibitors. The resulted hits were selected, based on the binding affinities, docking scores and selectivity. Further, binding energy calculation, Lipinski filtration and ADMET prediction were carried out to find safe and better hits against MARK4. Best 10 compounds bearing high specificity and binding efficiency were selected, and their binding pattern to MARK4 was analyzed in detail. Finally, 100 ns molecular dynamics simulation was performed to evaluate; the dynamics stability of MARK4-compound complex. In conclusion, these selected natural compounds from ZINC database might be potential leads against MARK4, and can further be exploited in drug design and development for associated diseases.
- Full Text:
- Date Issued: 2019
- Authors: Mohammad, Taj , Khan, Faez I , Lobb, Kevin A , Islam, Asimul , Ahmad, Faizan , Hassan, M Imtaiyaz
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447159 , vital:74588 , xlink:href="https://doi.org/10.1080/07391102.2018.1468282"
- Description: Microtubule affinity-regulating kinase 4 (MARK4) has recently been identified as a potential drug target for several complex diseases including cancer, diabetes and neurodegenerative disorders. Inhibition of MARK4 activity is an appealing therapeutic option to treat such diseases. Here, we have performed structure-based virtual high-throughput screening of 100,000 naturally occurring compounds from ZINC database against MARK4 to find its potential inhibitors. The resulted hits were selected, based on the binding affinities, docking scores and selectivity. Further, binding energy calculation, Lipinski filtration and ADMET prediction were carried out to find safe and better hits against MARK4. Best 10 compounds bearing high specificity and binding efficiency were selected, and their binding pattern to MARK4 was analyzed in detail. Finally, 100 ns molecular dynamics simulation was performed to evaluate; the dynamics stability of MARK4-compound complex. In conclusion, these selected natural compounds from ZINC database might be potential leads against MARK4, and can further be exploited in drug design and development for associated diseases.
- Full Text:
- Date Issued: 2019
An evaluation of the regulation and enforcement of trade mark and domain name rights in South Africa
- Authors: Maunganidze, Tendai
- Date: 2007
- Subjects: Trademarks -- Law and legislation -- South Africa Internet domain names -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3714 , http://hdl.handle.net/10962/d1007571
- Description: The conflict between trade marks and domain names has been a major subject of legal debate over the past few years. The issues arising from the relationship between trade marks and domain names reveal the difficulties associated with attempts to establish mechanisms to address the problems existing between them. Trade mark laws have been adopted to resolve the trade mark and domain name conflict, resulting in more conflict. Domain name registers have to date been constructed on the basis of first come first served. Given that the generic indicators are very general, it has been inevitable that problems would arise, particularly once the commercial potential of the Internet began to be realised. Unlike domain names, trade marks are protected in ways which are more precise. Trade marks may not be imitated either exactly or in a manner so similar that it is likely to confuse a significant portion of the public. It is possible for more than one enterprise to use the same trade mark in respect of different goods, although this is not possible with domain names. This disparity in objectives leads to two core problems. The first problem relates to cybersquatters who deliberately secure Top Level Domains (TLDs) containing the names or marks of well known enterprises in order to sell them later. The second problem relates to the rival claims between parties who have genuine reasons for wanting particular TLDs, and problems associated with the resolution of such claims. The disputes between parties with legitimate conflicting interests in domain names are often not equitably and effectively resolved, thus compromising the rights of domain name holders. There is great activity in the United States of America (USA) and the United Kingdom (UK) to provide a more substantial system of governing and regulating the Internet. There is a strong movement to provide methods of arbitrating conflicts between honest claims to TLDs which conflict either in Internet terms or in trade mark law. However, these difficult policies remain to be settled. South Africa's progress towards the establishment of an effective mechanism to govern and regulate the Internet has been hindered by the absence of a policy to resolve domain related trade mark disputes. South Africa only recently drafted the South African Regulations for Alternative Domain Name Dispute Resolution (zaADRR), although the regulations have not yet been adopted. Therefore South African parties to domain name disputes continue to find solutions to their problems through the court system or foreign dispute resolution policies. The purpose of this study is firstly to examine and to comment on the basic issues of trade mark law and domain names in this area, with particular reference to South Africa, and secondly to examine the mechanisms in place for the resolution of trade mark and domain name disputes and to highlight the issues that flow from that. An additional purpose of this study is to discuss the policies of the dispute resolution mechanisms and to suggest how these policies can be improved.
- Full Text:
- Date Issued: 2007
An evaluation of the regulation and enforcement of trade mark and domain name rights in South Africa
- Authors: Maunganidze, Tendai
- Date: 2007
- Subjects: Trademarks -- Law and legislation -- South Africa Internet domain names -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3714 , http://hdl.handle.net/10962/d1007571
- Description: The conflict between trade marks and domain names has been a major subject of legal debate over the past few years. The issues arising from the relationship between trade marks and domain names reveal the difficulties associated with attempts to establish mechanisms to address the problems existing between them. Trade mark laws have been adopted to resolve the trade mark and domain name conflict, resulting in more conflict. Domain name registers have to date been constructed on the basis of first come first served. Given that the generic indicators are very general, it has been inevitable that problems would arise, particularly once the commercial potential of the Internet began to be realised. Unlike domain names, trade marks are protected in ways which are more precise. Trade marks may not be imitated either exactly or in a manner so similar that it is likely to confuse a significant portion of the public. It is possible for more than one enterprise to use the same trade mark in respect of different goods, although this is not possible with domain names. This disparity in objectives leads to two core problems. The first problem relates to cybersquatters who deliberately secure Top Level Domains (TLDs) containing the names or marks of well known enterprises in order to sell them later. The second problem relates to the rival claims between parties who have genuine reasons for wanting particular TLDs, and problems associated with the resolution of such claims. The disputes between parties with legitimate conflicting interests in domain names are often not equitably and effectively resolved, thus compromising the rights of domain name holders. There is great activity in the United States of America (USA) and the United Kingdom (UK) to provide a more substantial system of governing and regulating the Internet. There is a strong movement to provide methods of arbitrating conflicts between honest claims to TLDs which conflict either in Internet terms or in trade mark law. However, these difficult policies remain to be settled. South Africa's progress towards the establishment of an effective mechanism to govern and regulate the Internet has been hindered by the absence of a policy to resolve domain related trade mark disputes. South Africa only recently drafted the South African Regulations for Alternative Domain Name Dispute Resolution (zaADRR), although the regulations have not yet been adopted. Therefore South African parties to domain name disputes continue to find solutions to their problems through the court system or foreign dispute resolution policies. The purpose of this study is firstly to examine and to comment on the basic issues of trade mark law and domain names in this area, with particular reference to South Africa, and secondly to examine the mechanisms in place for the resolution of trade mark and domain name disputes and to highlight the issues that flow from that. An additional purpose of this study is to discuss the policies of the dispute resolution mechanisms and to suggest how these policies can be improved.
- Full Text:
- Date Issued: 2007
The elucidation of nickel and zinc based Metal Organic Frameworks (MOFs) using a polycarboxylate-benzene ligand: a synthetic, spectroscopic, and thermoanalytical study
- Authors: Hodgson, Ivan Mark
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/290877 , vital:56795
- Description: Thesis (MSc) -- Faculty of Science, Chemistry, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Hodgson, Ivan Mark
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/290877 , vital:56795
- Description: Thesis (MSc) -- Faculty of Science, Chemistry, 2022
- Full Text:
- Date Issued: 2022-04-06
Frozen in time to reclaiming one's life: the evaluation of the Ehlers and Clark Cognitive Therapy Model in the assessment and treatment of a hijacking survivor
- Authors: Smith, Tracy-Ann
- Date: 2006
- Subjects: Cognitive therapy -- Methods , Post-traumatic stress disorder -- Patients -- Rehabilitation -- South Africa , Post-traumatic stress disorder -- Patients -- Case studies -- South Africa , Post-traumatic stress disorder -- Treatment -- South Africa , Victims of crimes -- Counseling of
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3060 , http://hdl.handle.net/10962/d1002569 , Cognitive therapy -- Methods , Post-traumatic stress disorder -- Patients -- Rehabilitation -- South Africa , Post-traumatic stress disorder -- Patients -- Case studies -- South Africa , Post-traumatic stress disorder -- Treatment -- South Africa , Victims of crimes -- Counseling of
- Description: The aim of this research study was achieved by providing support for the effectiveness and the transportability of the Ehlers and Clark (2000) cognitive therapy model for the assessment and treatment of PTSD. Furthermore, the contextual factors which were important in this case were investigated and documented. However, research within the social sciences will inevitably produce various limitations due to the unique individuals and dynamic phenomena that are studied.
- Full Text:
- Date Issued: 2006
- Authors: Smith, Tracy-Ann
- Date: 2006
- Subjects: Cognitive therapy -- Methods , Post-traumatic stress disorder -- Patients -- Rehabilitation -- South Africa , Post-traumatic stress disorder -- Patients -- Case studies -- South Africa , Post-traumatic stress disorder -- Treatment -- South Africa , Victims of crimes -- Counseling of
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3060 , http://hdl.handle.net/10962/d1002569 , Cognitive therapy -- Methods , Post-traumatic stress disorder -- Patients -- Rehabilitation -- South Africa , Post-traumatic stress disorder -- Patients -- Case studies -- South Africa , Post-traumatic stress disorder -- Treatment -- South Africa , Victims of crimes -- Counseling of
- Description: The aim of this research study was achieved by providing support for the effectiveness and the transportability of the Ehlers and Clark (2000) cognitive therapy model for the assessment and treatment of PTSD. Furthermore, the contextual factors which were important in this case were investigated and documented. However, research within the social sciences will inevitably produce various limitations due to the unique individuals and dynamic phenomena that are studied.
- Full Text:
- Date Issued: 2006
An examination of the literary quality of two reading schemes
- Authors: Waters, Nigel Bruce
- Date: 1988
- Subjects: Reading (Primary) , Reading -- Language experience approach , Readability (Literary style)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1345 , http://hdl.handle.net/10962/d1001411
- Description: Learning to read is one of the most crucial life tasks that the young child must acquire whilst in primary school. In modern society, much of what one does is dependant on having the ability to read. While a great deal of research has focused on how children learn to read, relatively little attention has been paid to the literary quality of the material the children are exposed to whilst learning to read. In the past few years I have become increasingly concerned with the number of teachers who use material designed for teaching children to read without being aware of the literary quality of the material. While numerous teachers are aware of the issues surrounding the learning to read debate and use up to date materials to teach reading, far too many accept the material supplied by the school without questioning its literary merit and its impact upon the young reader. This piece of research is an attempt to evaluate the literary quality of two reading schemes currently in use in Cape Education Department schools. The chief conclusion of the research is that the schemes examined fall far short of the standards required for them to be considered good literature. Although the research is limited to two reading schemes, it is hoped that a teacher using other schemes could use the framework supplied in this study to examine the literary quality of the material she is using. Furthermore, the final chapter offers suggestions as to how to replace material of poor literary quality with books of a higher literary standard. On the basis of the above findings it is suggested that there is a need for individual teachers, schools, teacher training institutions and the Cape Education Department to examine the literary quality of reading schemes and books that are used in the process of teaching children to read. It is hoped that this piece of research will create a greater awareness amongst teachers of the literary quality of reading materials and prompt further research into such materials that will be of benefit to the central character in this study; the young child learning to read
- Full Text:
- Date Issued: 1988
- Authors: Waters, Nigel Bruce
- Date: 1988
- Subjects: Reading (Primary) , Reading -- Language experience approach , Readability (Literary style)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1345 , http://hdl.handle.net/10962/d1001411
- Description: Learning to read is one of the most crucial life tasks that the young child must acquire whilst in primary school. In modern society, much of what one does is dependant on having the ability to read. While a great deal of research has focused on how children learn to read, relatively little attention has been paid to the literary quality of the material the children are exposed to whilst learning to read. In the past few years I have become increasingly concerned with the number of teachers who use material designed for teaching children to read without being aware of the literary quality of the material. While numerous teachers are aware of the issues surrounding the learning to read debate and use up to date materials to teach reading, far too many accept the material supplied by the school without questioning its literary merit and its impact upon the young reader. This piece of research is an attempt to evaluate the literary quality of two reading schemes currently in use in Cape Education Department schools. The chief conclusion of the research is that the schemes examined fall far short of the standards required for them to be considered good literature. Although the research is limited to two reading schemes, it is hoped that a teacher using other schemes could use the framework supplied in this study to examine the literary quality of the material she is using. Furthermore, the final chapter offers suggestions as to how to replace material of poor literary quality with books of a higher literary standard. On the basis of the above findings it is suggested that there is a need for individual teachers, schools, teacher training institutions and the Cape Education Department to examine the literary quality of reading schemes and books that are used in the process of teaching children to read. It is hoped that this piece of research will create a greater awareness amongst teachers of the literary quality of reading materials and prompt further research into such materials that will be of benefit to the central character in this study; the young child learning to read
- Full Text:
- Date Issued: 1988
Poetry's next-door neighbour: inaugural lecture delivered at Rhodes University
- Authors: Suggit, John
- Date: 1977
- Subjects: Jesus Christ -- Betrayla , Bible. Gospels -- Criticism, interpretation, etc. , Kissing -- Religious aspects
- Language: English
- Type: Text
- Identifier: vital:672 , http://hdl.handle.net/10962/d1020741 , ISBN 0949980935
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1977
- Authors: Suggit, John
- Date: 1977
- Subjects: Jesus Christ -- Betrayla , Bible. Gospels -- Criticism, interpretation, etc. , Kissing -- Religious aspects
- Language: English
- Type: Text
- Identifier: vital:672 , http://hdl.handle.net/10962/d1020741 , ISBN 0949980935
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1977
From Pringles of the Valleys
- Pringle, Eric, 1907-, Pringle, Mark Elliot, 1880-, Pringle, John Adams, 1910-
- Authors: Pringle, Eric, 1907- , Pringle, Mark Elliot, 1880- , Pringle, John Adams, 1910-
- Date: 1957
- Subjects: Acacia karroo -- South Africa , Trees -- South Africa
- Language: English
- Type: mixed material , essay
- Identifier: http://hdl.handle.net/10962/109198 , vital:33084
- Description: Transcript: "from PRINGLES OF THE VALLEYS ,1957, by Eric, Mark and John Pringle. p.29. (On the farm now known as Clifton). "The next day, July 2nd (1820) was our first Sunday on our own grounds. Feeling deeply the importance of maintaining the suitable observance of this day of sacred rest, it was unanimously resolved that we should strictly abstain from an secular employment not sanctioned by absolute necessity; and at the same time commence such a system of religious services as might be with propriety maintained in the absence of a clergyman or minister. The whole party were accordingly assembled after breakfast under a venerable acacia tree, on the margin of a little stream which murmured around our camp. It was, indeed, an affecting sight to look round on our little band of Scottish emigrants, thus congregated for the first time to worship God in the wild glen allotted for their future home and the heritage of their offspring". An inspection in 1956 established this spot with some certainty is just south of the present Craig Rennie homestead".
- Full Text:
- Date Issued: 1957
- Authors: Pringle, Eric, 1907- , Pringle, Mark Elliot, 1880- , Pringle, John Adams, 1910-
- Date: 1957
- Subjects: Acacia karroo -- South Africa , Trees -- South Africa
- Language: English
- Type: mixed material , essay
- Identifier: http://hdl.handle.net/10962/109198 , vital:33084
- Description: Transcript: "from PRINGLES OF THE VALLEYS ,1957, by Eric, Mark and John Pringle. p.29. (On the farm now known as Clifton). "The next day, July 2nd (1820) was our first Sunday on our own grounds. Feeling deeply the importance of maintaining the suitable observance of this day of sacred rest, it was unanimously resolved that we should strictly abstain from an secular employment not sanctioned by absolute necessity; and at the same time commence such a system of religious services as might be with propriety maintained in the absence of a clergyman or minister. The whole party were accordingly assembled after breakfast under a venerable acacia tree, on the margin of a little stream which murmured around our camp. It was, indeed, an affecting sight to look round on our little band of Scottish emigrants, thus congregated for the first time to worship God in the wild glen allotted for their future home and the heritage of their offspring". An inspection in 1956 established this spot with some certainty is just south of the present Craig Rennie homestead".
- Full Text:
- Date Issued: 1957
An enquiry into the formative and summative assessment procedures, and perceptions thereof, of grade 10 mathematics teachers : a Namibian case study
- Authors: Marongwe, Anesu Desmond
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1385 , http://hdl.handle.net/10962/d1001513
- Description: The purpose of this study was to gain insight into observed discrepancies between continuous assessment and final examination average marks in Grade 10 Mathematics in the Oshikoto region of Namibia. The study is framed as a case study and is grounded within the interpretive paradigm. A mixed methods approach was applied, eliciting both quantitative as well as qualitative data. The study took place in two phases. In Phase 1, continuous assessment and Grade 10 final examination average marks for 62 Junior Secondary Schools for the period 2008-2010 were gathered and analyzed. Schools were characterized in terms of the relationship between their continuous assessment and final examination average marks for each of the three years. Phase 2, which was informed by Phase 1, took the form of structured interviews with a sample of three Mathematics teachers and three principals along with a focus-group interview of twelve teachers in order to investigate more deeply the perceptions of teachers and principals toward assessment policy and practice. The study shows that Grade 10 assessment practice in Namibian schools is far from ideal. Many teachers are not fully conversant with the various continuous assessment components as outlined by policy, and teachers are not confident about setting appropriate continuous assessment tasks. There is a strong perception that continuous assessment marks can easily be inflated and those teachers who gave high continuous assessment marks to their learners were generally perceived as being either incompetent or dishonest. While continuous assessment was seen as an important component of teaching and learning, it is evident that teachers and principals would welcome greater clarity, along with standardization and moderation, with respect to continuous assessment practice.
- Full Text:
- Date Issued: 2013
- Authors: Marongwe, Anesu Desmond
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1385 , http://hdl.handle.net/10962/d1001513
- Description: The purpose of this study was to gain insight into observed discrepancies between continuous assessment and final examination average marks in Grade 10 Mathematics in the Oshikoto region of Namibia. The study is framed as a case study and is grounded within the interpretive paradigm. A mixed methods approach was applied, eliciting both quantitative as well as qualitative data. The study took place in two phases. In Phase 1, continuous assessment and Grade 10 final examination average marks for 62 Junior Secondary Schools for the period 2008-2010 were gathered and analyzed. Schools were characterized in terms of the relationship between their continuous assessment and final examination average marks for each of the three years. Phase 2, which was informed by Phase 1, took the form of structured interviews with a sample of three Mathematics teachers and three principals along with a focus-group interview of twelve teachers in order to investigate more deeply the perceptions of teachers and principals toward assessment policy and practice. The study shows that Grade 10 assessment practice in Namibian schools is far from ideal. Many teachers are not fully conversant with the various continuous assessment components as outlined by policy, and teachers are not confident about setting appropriate continuous assessment tasks. There is a strong perception that continuous assessment marks can easily be inflated and those teachers who gave high continuous assessment marks to their learners were generally perceived as being either incompetent or dishonest. While continuous assessment was seen as an important component of teaching and learning, it is evident that teachers and principals would welcome greater clarity, along with standardization and moderation, with respect to continuous assessment practice.
- Full Text:
- Date Issued: 2013
Evidence for supposing that our Greek text of the gospel of St Mark is translated from Latin, that most of this Latin still survives, and that by following the Latin we can recover words and actions of Jesus which have been falsified in the Greek translation : inaugural lecture delivere at Rhodes University
- Authors: Gain, D B
- Date: 1978
- Subjects: Bible. Mark -- Translating , Bible. Mark -- Versions , Rhodes University -- History
- Language: English
- Type: text
- Identifier: vital:626 , http://hdl.handle.net/10962/d1020695
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
- Authors: Gain, D B
- Date: 1978
- Subjects: Bible. Mark -- Translating , Bible. Mark -- Versions , Rhodes University -- History
- Language: English
- Type: text
- Identifier: vital:626 , http://hdl.handle.net/10962/d1020695
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
Avian thermoregulation in the heat: is evaporative cooling more economical in nocturnal birds?
- O'Connor, Ryan S, Smit, Ben, Talbot, William A, Gerson, Alexander R, Brigham, R Mark, Wolf, Blair O, McKechnie, Andrew E
- Authors: O'Connor, Ryan S , Smit, Ben , Talbot, William A , Gerson, Alexander R , Brigham, R Mark , Wolf, Blair O , McKechnie, Andrew E
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441518 , vital:73895 , https://journals.biologists.com/jeb/article/221/17/jeb181420/19595/Avian-thermoregulation-in-the-heat-is-evaporative
- Description: Evaporative cooling is a prerequisite for avian occupancy of hot, arid environments, and is the only avenue of heat dissipation when air temperatures (Ta) exceed body temperature (Tb). Whereas diurnal birds can potentially rehydrate throughout the day, nocturnal species typically forgo drinking between sunrise and sunset. We hypothesized that nocturnal birds have evolved reduced rates of evaporative water loss (EWL) and more economical evaporative cooling mechanisms compared with diurnal species, permitting nocturnal species to tolerate extended periods of intense heat without becoming lethally dehydrated. We used phylogenetically informed regressions to compare EWL and evaporative cooling efficiency [ratio of evaporative heat loss (EHL) and metabolic heat production (MHP); EHL/MHP] among nocturnal and diurnal birds at high Ta. We analyzed variation in three response variables: (1) slope of EWL at Ta between 40 and 46°C, (2) EWL at Ta=46°C and (3) EHL/MHP at Ta=46°C. Nocturnality emerged as a weak, negative predictor, with nocturnal species having slightly shallower slopes and reduced EWL compared with diurnal species of similar mass.
- Full Text:
- Date Issued: 2018
- Authors: O'Connor, Ryan S , Smit, Ben , Talbot, William A , Gerson, Alexander R , Brigham, R Mark , Wolf, Blair O , McKechnie, Andrew E
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441518 , vital:73895 , https://journals.biologists.com/jeb/article/221/17/jeb181420/19595/Avian-thermoregulation-in-the-heat-is-evaporative
- Description: Evaporative cooling is a prerequisite for avian occupancy of hot, arid environments, and is the only avenue of heat dissipation when air temperatures (Ta) exceed body temperature (Tb). Whereas diurnal birds can potentially rehydrate throughout the day, nocturnal species typically forgo drinking between sunrise and sunset. We hypothesized that nocturnal birds have evolved reduced rates of evaporative water loss (EWL) and more economical evaporative cooling mechanisms compared with diurnal species, permitting nocturnal species to tolerate extended periods of intense heat without becoming lethally dehydrated. We used phylogenetically informed regressions to compare EWL and evaporative cooling efficiency [ratio of evaporative heat loss (EHL) and metabolic heat production (MHP); EHL/MHP] among nocturnal and diurnal birds at high Ta. We analyzed variation in three response variables: (1) slope of EWL at Ta between 40 and 46°C, (2) EWL at Ta=46°C and (3) EHL/MHP at Ta=46°C. Nocturnality emerged as a weak, negative predictor, with nocturnal species having slightly shallower slopes and reduced EWL compared with diurnal species of similar mass.
- Full Text:
- Date Issued: 2018
An analysis of the factors that influence effectiveness in information technology student project teams
- Authors: Patrellis, Yiota
- Date: 2003
- Subjects: Information technology -- Management , Project management , Teams in the workplace , Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MTech (Information Technology)
- Identifier: vital:10800 , http://hdl.handle.net/10948/199 , Information technology -- Management , Project management , Teams in the workplace , Organizational effectiveness
- Description: More and more organizations are making use of teamwork. Effective teams are also important from an Information Technology (IT) perspective, since teamwork forms an integral part of all software development activities. It is therefore extremely important that IT students are able to work together as an effective team. These statements lead to the following questions – How can IT student project teams be effective and what obstacles need to be overcome in order to ensure effectiveness? This dissertation reports on an exploratory study of second and third year IT project teams and exposes factors that lead to ineffectiveness. Firstly, the problems experienced by the groups seem to have the largest detrimental effect on effective team functioning. Secondly, the project mark is also affected by the priority issue that is associated with the particular task. Thirdly, the issues of time management, communication, conflict management, compromise, social loafing and group cohesion also play an important role in team effectiveness. This dissertation sets out to prove that the key to "effectiveness" lies in empowering the student to deal with all possible dilemmas that may be faced when working in teams in the tertiary team situation. The benefits of these actions will hopefully lead to the realization of “effectiveness” in the tertiary team situation and ultimately, in the student’s work environment.
- Full Text:
- Date Issued: 2003
- Authors: Patrellis, Yiota
- Date: 2003
- Subjects: Information technology -- Management , Project management , Teams in the workplace , Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MTech (Information Technology)
- Identifier: vital:10800 , http://hdl.handle.net/10948/199 , Information technology -- Management , Project management , Teams in the workplace , Organizational effectiveness
- Description: More and more organizations are making use of teamwork. Effective teams are also important from an Information Technology (IT) perspective, since teamwork forms an integral part of all software development activities. It is therefore extremely important that IT students are able to work together as an effective team. These statements lead to the following questions – How can IT student project teams be effective and what obstacles need to be overcome in order to ensure effectiveness? This dissertation reports on an exploratory study of second and third year IT project teams and exposes factors that lead to ineffectiveness. Firstly, the problems experienced by the groups seem to have the largest detrimental effect on effective team functioning. Secondly, the project mark is also affected by the priority issue that is associated with the particular task. Thirdly, the issues of time management, communication, conflict management, compromise, social loafing and group cohesion also play an important role in team effectiveness. This dissertation sets out to prove that the key to "effectiveness" lies in empowering the student to deal with all possible dilemmas that may be faced when working in teams in the tertiary team situation. The benefits of these actions will hopefully lead to the realization of “effectiveness” in the tertiary team situation and ultimately, in the student’s work environment.
- Full Text:
- Date Issued: 2003
The influence of academic interventions on the academic performance of human resource management students
- Authors: Hiles, Tevin
- Date: 2020
- Subjects: Academic performance -- South Africa , Educational psychology Learning, Psychology of
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/50568 , vital:42222
- Description: There are many contextual challenges related to this problem. Some of these include the mass of diverse students entering tertiary institutions and the level of educational preparedness of these students. Moreover, the lasting legacy of Apartheid brings its own challenges in relation to widening access for students entering South African higher education institutions. There are considerable repercussions related to the costs of re-educating students and re-admitting failing students into continuously growing classes. Furthermore, there is a protruding argument that the level of student readiness/preparedness is continually declining. The above-mentioned challenges place extreme pressure on higher education institutions and their staff to provide academic support to students, along with maintaining adequate pass rates. Reflecting on the challenges faced in the South African higher educational context, it is evident that the development and implementation of academic support programmes are important. These programmes are aimed at providing quality learning and teaching and counteracting declining success rates. In addition, there is a need to transform how massification of higher education takes place, to address the challenges of diverse student profiles, dropout rates and low throughput rates. This study explored the impact of academic support interventions on academic performance by focusing on student engagement as it is the leading factor of academic success. For the purpose of this study, this was measured through the attendance of academic interventions. Student engagement may be defined as the time and energy learners dedicate to educational activities both inside and outside of the classroom, along with the policies and practices institutions use to persuade students to partake in these activities. The findings revealed that academic interventions indeed have a positive influence on student behaviour and student academic progress. The results of this study could assist the department of HRM in determining the effectiveness of academic interventions created for first year students.
- Full Text:
- Date Issued: 2020
- Authors: Hiles, Tevin
- Date: 2020
- Subjects: Academic performance -- South Africa , Educational psychology Learning, Psychology of
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/50568 , vital:42222
- Description: There are many contextual challenges related to this problem. Some of these include the mass of diverse students entering tertiary institutions and the level of educational preparedness of these students. Moreover, the lasting legacy of Apartheid brings its own challenges in relation to widening access for students entering South African higher education institutions. There are considerable repercussions related to the costs of re-educating students and re-admitting failing students into continuously growing classes. Furthermore, there is a protruding argument that the level of student readiness/preparedness is continually declining. The above-mentioned challenges place extreme pressure on higher education institutions and their staff to provide academic support to students, along with maintaining adequate pass rates. Reflecting on the challenges faced in the South African higher educational context, it is evident that the development and implementation of academic support programmes are important. These programmes are aimed at providing quality learning and teaching and counteracting declining success rates. In addition, there is a need to transform how massification of higher education takes place, to address the challenges of diverse student profiles, dropout rates and low throughput rates. This study explored the impact of academic support interventions on academic performance by focusing on student engagement as it is the leading factor of academic success. For the purpose of this study, this was measured through the attendance of academic interventions. Student engagement may be defined as the time and energy learners dedicate to educational activities both inside and outside of the classroom, along with the policies and practices institutions use to persuade students to partake in these activities. The findings revealed that academic interventions indeed have a positive influence on student behaviour and student academic progress. The results of this study could assist the department of HRM in determining the effectiveness of academic interventions created for first year students.
- Full Text:
- Date Issued: 2020
The influence of academic interventions on the academic performance of human resource management students
- Authors: Hiles, Tevin
- Date: 2020
- Subjects: Academic achievement -- South Africa , Education, Higher -- Evaluation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/49846 , vital:41808
- Description: There are many contextual challenges related to this problem. Some of these include the mass of diverse students entering tertiary institutions and the level of educational preparedness of these students. Moreover, the lasting legacy of Apartheid brings its own challenges in relation to widening access for students entering South African higher education institutions. There are considerable repercussions related to the costs of re-educating students and re-admitting failing students into continuously growing classes. Furthermore, there is a protruding argument that the level of student readiness/preparedness is continually declining. The above-mentioned challenges place extreme pressure on higher education institutions and their staff to provide academic support to students, along with maintaining adequate pass rates. Reflecting on the challenges faced in the South African higher educational context, it is evident that the development and implementation of academic support programmes are important. These programmes are aimed at providing quality learning and teaching and counteracting declining success rates. In addition, there is a need to transform how massification of higher education takes place, to address the challenges of diverse student profiles, dropout rates and low throughput rates. This study explored the impact of academic support interventions on academic performance by focusing on student engagement as it is the leading factor of academic success. For the purpose of this study, this was measured through the attendance of academic interventions. Student engagement may be defined as the time and energy learners dedicate to educational activities both inside and outside of the classroom, along with the policies and practices institutions use to persuade students to partake in these activities. The findings revealed that academic interventions indeed have a positive influence on student behaviour and student academic progress. The results of this study could assist the department of HRM in determining the effectiveness of academic interventions created for first year students.
- Full Text:
- Date Issued: 2020
- Authors: Hiles, Tevin
- Date: 2020
- Subjects: Academic achievement -- South Africa , Education, Higher -- Evaluation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/49846 , vital:41808
- Description: There are many contextual challenges related to this problem. Some of these include the mass of diverse students entering tertiary institutions and the level of educational preparedness of these students. Moreover, the lasting legacy of Apartheid brings its own challenges in relation to widening access for students entering South African higher education institutions. There are considerable repercussions related to the costs of re-educating students and re-admitting failing students into continuously growing classes. Furthermore, there is a protruding argument that the level of student readiness/preparedness is continually declining. The above-mentioned challenges place extreme pressure on higher education institutions and their staff to provide academic support to students, along with maintaining adequate pass rates. Reflecting on the challenges faced in the South African higher educational context, it is evident that the development and implementation of academic support programmes are important. These programmes are aimed at providing quality learning and teaching and counteracting declining success rates. In addition, there is a need to transform how massification of higher education takes place, to address the challenges of diverse student profiles, dropout rates and low throughput rates. This study explored the impact of academic support interventions on academic performance by focusing on student engagement as it is the leading factor of academic success. For the purpose of this study, this was measured through the attendance of academic interventions. Student engagement may be defined as the time and energy learners dedicate to educational activities both inside and outside of the classroom, along with the policies and practices institutions use to persuade students to partake in these activities. The findings revealed that academic interventions indeed have a positive influence on student behaviour and student academic progress. The results of this study could assist the department of HRM in determining the effectiveness of academic interventions created for first year students.
- Full Text:
- Date Issued: 2020
Enhancing phosphorus availability in some phosphate fixing soils of the Transkei region, South Africa using goat manure
- Authors: Gichangi, Elias Maina
- Date: 2007
- Subjects: Phosphorus in agriculture , Soils -- Phosphorus content , Phosphatic fertilizers , Soils -- Phosphorus content -- South Africa -- Transkei
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11960 , http://hdl.handle.net/10353/80 , Phosphorus in agriculture , Soils -- Phosphorus content , Phosphatic fertilizers , Soils -- Phosphorus content -- South Africa -- Transkei
- Description: Low availability of soil phosphorus (P) caused by strong sorption of P is a major constraint to agricultural production in most South African soils, particularly those from the high rainfall areas. The aim of this study was therefore to investigate whether combined addition of goat manure with inorganic P fertilizers could enhance P availability in some P fixing soils of the Transkei region, South Africa. The study addressed the following specific objectives (i) to assess P sorption capacities and requirements of selected soils and their relationship with selected soil properties and single point sorption test, (ii) to assess the effects of goat manure and lime addition on P sorption properties of selected P fixing soils (iii) to assess the temporal changes in concentration of inorganic and microbial biomass P fractions following application of inorganic fertilizer P with goat manure in a laboratory incubation experiment, and, (iv) to assess the effects of goat manure application with inorganic phosphate on inorganic and microbial biomass P fractions, P uptake and dry matter yield of maize. Sorption maxima (Smax) of seven soils examined ranged from 192.3 to 909.1 (mg P kg-1) and were highly and positively correlated with sorption affinity constant (r = 0.93, p = 0.01) and organic C (r = 0.71, p = 0.01). The amount of P required for maintaining a soil solution concentration of 0.2 mg P l-1 ranged from 2.1 to 123.5 mg P kg-1 soil. Soils collected from Qweqwe (a Cambisol), Qunu (an Acrisol), Ncihane (a Luvisol) and Bethania (a Ferralsol) had lower external P requirement values and were classified as lower sorbers, whereas soils from Ntlonyana (a Planosol), Chevy Chase (a Ferralsol) and Flagstaff (a Ferralsol) were classified as moderate sorbers. The results suggested that P availability could be compromised in 43 percent iii of the soils studied and that measures to mitigate the adverse effects of P sorption were needed to ensure that P is not a limiting factor to crop production, where such soils are found. Goat manure addition at varying rates (5, 10 and 20 tha-1 dry weight basis) to two of the moderately P fixing soils from Chevy Chase and Flagstaff, reduced P sorption maxima (Smax) compared to the control treatment. Phosphate sorption decreased with increasing amounts of goat manure in both soils but the extent of reduction was greater on Chevy Chase soil than on Flagstaff soil. The relative liming effects of the different rates of goat manure followed the order 20 t GM ha-1 > 10 t GM ha-1 > 5 t GM ha-1. In a separate experiment, addition of inorganic P at varying rates (0, 90, 180, and 360 kg P ha-1) to Flagstaff soil increased labile P fractions (resin P, biomass P and NaHCO3-Pi) and the increases were greater when goat manure was co-applied. The control treatments contained only 17.2 and 27.5 mg P kg-1 of resin extractable P in the un-amended and manure amended treatments, respectively which increased to 118.2 and 122.7 mg P kg-1 on day 28 of incubation. Biomass P concentration was increased from 16.8 to 43.9 mg P kg-1 in P alone treatments but the fraction was greatly enhanced with manure addition, increasing it from 32.6 to 97.7 mg P kg-1. NaOH-Pi was the largest extractable Pi fraction and ranged from 144.3 to 250.6 mg P kg-1 and 107.5 to 213.2 mg P kg-1 in the unamended and manure amended treatments, respectively. Dry matter yield and P uptake by maize grown in the glasshouse were highly and significantly (p = 0.05) correlated with the different P fractions in the soil. The correlations followed the order resin P (r = 0.85) > NaOH-Pi (r = 0.85) > NaHCO3-Pi (r = 0.84) >> biomass P (r = 0.56) for dry matter yield at 6 weeks after planting. At 12 weeks after planting, goat manure had iv highly significant effects on resin P and biomass P but had no effect on NaHCO3-Pi and NaOH–Pi. The combination of biomass P, resin P and NaHCO3-Pi explained 75.8 percent of the variation in dry matter yield of which 63.0 percent of the variation was explained by biomass P alone. The greatest increase in biomass P occurred when added P was co-applied with 5 or 10 tha-1 goat manure. The predictive equation for maize dry matter yield (DM) was: DM (g) = 1.897 biomass P + 0.645 resin P (r = 0.73). Resin P was the fraction that was most depleted due to plant uptake and decreased by 56 to 68 percent between the 6th week and the 12th week of sampling indicating that it played a greater role in supplying plant available P. The results therefore suggested that the use of goat manure may allow resource poor farmers to use lower levels of commercial phosphate fertilizers because of its effect to reduce soil P sorption. In addition, higher increases in biomass P due to manure addition observed at lower rates of added P indicated that goat manure has potential for enhancing bioavailability and fertilizer use efficiency of small inorganic P applications.
- Full Text:
- Date Issued: 2007
- Authors: Gichangi, Elias Maina
- Date: 2007
- Subjects: Phosphorus in agriculture , Soils -- Phosphorus content , Phosphatic fertilizers , Soils -- Phosphorus content -- South Africa -- Transkei
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11960 , http://hdl.handle.net/10353/80 , Phosphorus in agriculture , Soils -- Phosphorus content , Phosphatic fertilizers , Soils -- Phosphorus content -- South Africa -- Transkei
- Description: Low availability of soil phosphorus (P) caused by strong sorption of P is a major constraint to agricultural production in most South African soils, particularly those from the high rainfall areas. The aim of this study was therefore to investigate whether combined addition of goat manure with inorganic P fertilizers could enhance P availability in some P fixing soils of the Transkei region, South Africa. The study addressed the following specific objectives (i) to assess P sorption capacities and requirements of selected soils and their relationship with selected soil properties and single point sorption test, (ii) to assess the effects of goat manure and lime addition on P sorption properties of selected P fixing soils (iii) to assess the temporal changes in concentration of inorganic and microbial biomass P fractions following application of inorganic fertilizer P with goat manure in a laboratory incubation experiment, and, (iv) to assess the effects of goat manure application with inorganic phosphate on inorganic and microbial biomass P fractions, P uptake and dry matter yield of maize. Sorption maxima (Smax) of seven soils examined ranged from 192.3 to 909.1 (mg P kg-1) and were highly and positively correlated with sorption affinity constant (r = 0.93, p = 0.01) and organic C (r = 0.71, p = 0.01). The amount of P required for maintaining a soil solution concentration of 0.2 mg P l-1 ranged from 2.1 to 123.5 mg P kg-1 soil. Soils collected from Qweqwe (a Cambisol), Qunu (an Acrisol), Ncihane (a Luvisol) and Bethania (a Ferralsol) had lower external P requirement values and were classified as lower sorbers, whereas soils from Ntlonyana (a Planosol), Chevy Chase (a Ferralsol) and Flagstaff (a Ferralsol) were classified as moderate sorbers. The results suggested that P availability could be compromised in 43 percent iii of the soils studied and that measures to mitigate the adverse effects of P sorption were needed to ensure that P is not a limiting factor to crop production, where such soils are found. Goat manure addition at varying rates (5, 10 and 20 tha-1 dry weight basis) to two of the moderately P fixing soils from Chevy Chase and Flagstaff, reduced P sorption maxima (Smax) compared to the control treatment. Phosphate sorption decreased with increasing amounts of goat manure in both soils but the extent of reduction was greater on Chevy Chase soil than on Flagstaff soil. The relative liming effects of the different rates of goat manure followed the order 20 t GM ha-1 > 10 t GM ha-1 > 5 t GM ha-1. In a separate experiment, addition of inorganic P at varying rates (0, 90, 180, and 360 kg P ha-1) to Flagstaff soil increased labile P fractions (resin P, biomass P and NaHCO3-Pi) and the increases were greater when goat manure was co-applied. The control treatments contained only 17.2 and 27.5 mg P kg-1 of resin extractable P in the un-amended and manure amended treatments, respectively which increased to 118.2 and 122.7 mg P kg-1 on day 28 of incubation. Biomass P concentration was increased from 16.8 to 43.9 mg P kg-1 in P alone treatments but the fraction was greatly enhanced with manure addition, increasing it from 32.6 to 97.7 mg P kg-1. NaOH-Pi was the largest extractable Pi fraction and ranged from 144.3 to 250.6 mg P kg-1 and 107.5 to 213.2 mg P kg-1 in the unamended and manure amended treatments, respectively. Dry matter yield and P uptake by maize grown in the glasshouse were highly and significantly (p = 0.05) correlated with the different P fractions in the soil. The correlations followed the order resin P (r = 0.85) > NaOH-Pi (r = 0.85) > NaHCO3-Pi (r = 0.84) >> biomass P (r = 0.56) for dry matter yield at 6 weeks after planting. At 12 weeks after planting, goat manure had iv highly significant effects on resin P and biomass P but had no effect on NaHCO3-Pi and NaOH–Pi. The combination of biomass P, resin P and NaHCO3-Pi explained 75.8 percent of the variation in dry matter yield of which 63.0 percent of the variation was explained by biomass P alone. The greatest increase in biomass P occurred when added P was co-applied with 5 or 10 tha-1 goat manure. The predictive equation for maize dry matter yield (DM) was: DM (g) = 1.897 biomass P + 0.645 resin P (r = 0.73). Resin P was the fraction that was most depleted due to plant uptake and decreased by 56 to 68 percent between the 6th week and the 12th week of sampling indicating that it played a greater role in supplying plant available P. The results therefore suggested that the use of goat manure may allow resource poor farmers to use lower levels of commercial phosphate fertilizers because of its effect to reduce soil P sorption. In addition, higher increases in biomass P due to manure addition observed at lower rates of added P indicated that goat manure has potential for enhancing bioavailability and fertilizer use efficiency of small inorganic P applications.
- Full Text:
- Date Issued: 2007
Photophysicochemical behaviour and antimicrobial properties of monocarboxy Mg (II) and Al (III) phthalocyanine-magnetite conjugates
- Idowu, Mopelola A I, Xego, Solami, Arslanoglu, Yasin, Mark, John, Antunes, Edith M, Nyokong, Tebello
- Authors: Idowu, Mopelola A I , Xego, Solami , Arslanoglu, Yasin , Mark, John , Antunes, Edith M , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188205 , vital:44734 , xlink:href="https://doi.org/10.1016/j.saa.2017.12.052"
- Description: Asymmetric Mg (II) or Al (III) phthalocyanine (containing a COOH group and 3-pyridylsulfanyl units) was conjugated via an amide bond to amino functionalized magnetic nanoparticle (AIMN) to form MgPc-AIMN or AlPc-AIMN conjugate, and characterized. The photophysicochemical behaviour of the phthalocyanine–AIMN conjugates was investigated and compared to the asymmetric Pcs and to the simple mixture of Pc with AIMNs without a chemical bond, (MPc-AIMN (mixed)). The directed covalent linkage of AIMNs to the asymmetrical metallopthalocyanines afforded improvements in the singlet oxygen (ФΔ) and triplet state quantum yield (ФT) as well as singlet oxygen lifetimes for the MPcs–AIMN-linked conjugates compared to MPc-AIMN (mixed) and MPcs alone. The asymmetric phthalocyanines and their conjugates showed effective antimicrobial activity against Escherichia coli bacteria under illumination.
- Full Text:
- Date Issued: 2018
- Authors: Idowu, Mopelola A I , Xego, Solami , Arslanoglu, Yasin , Mark, John , Antunes, Edith M , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188205 , vital:44734 , xlink:href="https://doi.org/10.1016/j.saa.2017.12.052"
- Description: Asymmetric Mg (II) or Al (III) phthalocyanine (containing a COOH group and 3-pyridylsulfanyl units) was conjugated via an amide bond to amino functionalized magnetic nanoparticle (AIMN) to form MgPc-AIMN or AlPc-AIMN conjugate, and characterized. The photophysicochemical behaviour of the phthalocyanine–AIMN conjugates was investigated and compared to the asymmetric Pcs and to the simple mixture of Pc with AIMNs without a chemical bond, (MPc-AIMN (mixed)). The directed covalent linkage of AIMNs to the asymmetrical metallopthalocyanines afforded improvements in the singlet oxygen (ФΔ) and triplet state quantum yield (ФT) as well as singlet oxygen lifetimes for the MPcs–AIMN-linked conjugates compared to MPc-AIMN (mixed) and MPcs alone. The asymmetric phthalocyanines and their conjugates showed effective antimicrobial activity against Escherichia coli bacteria under illumination.
- Full Text:
- Date Issued: 2018
A comparison of three techniques for fluorochrome marking of juvenile Clarias gariepinus otoliths
- Wartenberg, Reece, Booth, Anthony J, Weyl, Olaf L F
- Authors: Wartenberg, Reece , Booth, Anthony J , Weyl, Olaf L F
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123520 , vital:35450 , https://doi.10.3377/004.046.0119
- Description: African sharptooth catfish, Clarias gariepinus (Burchell 1822), is widely distributed with a natural range that extends from southern Turkey to the Orange River, South Africa (Skelton 2001). In addition to translocations within its southerly range (Cambray 2003), Cambray (2005) noted that as a result of poor aquaculture practices and introductions from a number of unknown sources, C. gariepinus has now invaded South America, Europe, Asia, and Australia. Its life history characteristics include a fast growth rate to a maximum length of 1300mmtotal length (TL) (Bruton 1976), a high fecundity, an omnivorous diet and the ability to breathe air (de Moor & Bruton 1988; Cambray 2003). Understanding the biology and population dynamics of this invader would assist in its management and possibly eradication.
- Full Text:
- Date Issued: 2011
- Authors: Wartenberg, Reece , Booth, Anthony J , Weyl, Olaf L F
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123520 , vital:35450 , https://doi.10.3377/004.046.0119
- Description: African sharptooth catfish, Clarias gariepinus (Burchell 1822), is widely distributed with a natural range that extends from southern Turkey to the Orange River, South Africa (Skelton 2001). In addition to translocations within its southerly range (Cambray 2003), Cambray (2005) noted that as a result of poor aquaculture practices and introductions from a number of unknown sources, C. gariepinus has now invaded South America, Europe, Asia, and Australia. Its life history characteristics include a fast growth rate to a maximum length of 1300mmtotal length (TL) (Bruton 1976), a high fecundity, an omnivorous diet and the ability to breathe air (de Moor & Bruton 1988; Cambray 2003). Understanding the biology and population dynamics of this invader would assist in its management and possibly eradication.
- Full Text:
- Date Issued: 2011
An investigation into the role that knowledge of the nature of mathematics and other factors play in determining motivation for further study of mathematics after std 7 in selected provincial secondary schools
- Authors: Arguile, David Ian
- Date: 1988
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1352 , http://hdl.handle.net/10962/d1001418
- Description: This study involves an investigation into reasons why pupils continue with mathematics after Std 7. The sample, consisting of Std 8 and Std 10 mathematics pupils at six academic, English-medium high schools in Port Elizabeth, had to complete a short questionnaire during the third term of 1985. It was found that most pupils continue with mathematics because of requirements for certain post-matric courses, to improve their career options and for other reasons classified in this investigation as "extrinsic", i.e. reasons that are not directly related to the nature of mathematics. An attempt is made to determine the extent of the pupils' knowledge of the nature of mathematics. Questions relating to the nature of mathematics are poorly answered by almost all of the pupils, thereby suggesting that this aspect of mathematics is sadly neglected in mathematics courses. The suggestion is made that this lack of knowledge of the nature of mathematics is linked to pupils' decisions to continue with the subject. The conclusion is drawn that unless more attention is given to conveying to pupils something of the nature of mathematics, there will be an increasing proportion of pupils who choose to continue with mathematics for the "wrong" reasons. This, in turn, has possible negative implications for mathematics education in general. Attention is also paid to differences re the above in respect of groupings based on standard, mathematical grade, sex, mathematical achievement and type of schooling. Although no conclusive findings are made other than with regard to specific questions, enough evidence of differences in certain of the groupings is produced to warrant further investigation
- Full Text:
- Date Issued: 1988
- Authors: Arguile, David Ian
- Date: 1988
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1352 , http://hdl.handle.net/10962/d1001418
- Description: This study involves an investigation into reasons why pupils continue with mathematics after Std 7. The sample, consisting of Std 8 and Std 10 mathematics pupils at six academic, English-medium high schools in Port Elizabeth, had to complete a short questionnaire during the third term of 1985. It was found that most pupils continue with mathematics because of requirements for certain post-matric courses, to improve their career options and for other reasons classified in this investigation as "extrinsic", i.e. reasons that are not directly related to the nature of mathematics. An attempt is made to determine the extent of the pupils' knowledge of the nature of mathematics. Questions relating to the nature of mathematics are poorly answered by almost all of the pupils, thereby suggesting that this aspect of mathematics is sadly neglected in mathematics courses. The suggestion is made that this lack of knowledge of the nature of mathematics is linked to pupils' decisions to continue with the subject. The conclusion is drawn that unless more attention is given to conveying to pupils something of the nature of mathematics, there will be an increasing proportion of pupils who choose to continue with mathematics for the "wrong" reasons. This, in turn, has possible negative implications for mathematics education in general. Attention is also paid to differences re the above in respect of groupings based on standard, mathematical grade, sex, mathematical achievement and type of schooling. Although no conclusive findings are made other than with regard to specific questions, enough evidence of differences in certain of the groupings is produced to warrant further investigation
- Full Text:
- Date Issued: 1988
Experiences of undergraduate diagnostic radiography students regarding assessor feedback during summative clinical assessments
- Authors: Hodgson, Hayley Dianne
- Date: 2019
- Subjects: Medical education , Teacher-student relationships Communication in education Mentoring in education Radiography, Medical -- Digital techniques
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/42296 , vital:36643
- Description: Assessment and feedback are closely interlinked terms. High quality feedback within education and assessment can have a profound influence on learning. Summative clinical assessments and feedback, conducted in clinical training sites, are vital steps in successfully preparing an undergraduate diagnostic radiography student for the desired outcome of a competent, skilled diagnostic radiographer. Feedback has the potential to close the gap between a student’s actual clinical performance and desired clinical performance. Despite the importance of feedback, students across the globe, particularly in the health professions, are dissatisfied with the current feedback systems. Failure to provide effective feedback within the clinical context can be detrimental to patient safety because students have a false impression of their clinical skills and competencies. The aim of the study was to explore and describe the experiences of undergraduate diagnostic radiography students regarding assessor feedback during summative clinical assessments. A qualitative, exploratory, descriptive, and contextual research design was used to gain in-depth knowledge of the experiences of undergraduate diagnostic radiography students regarding assessor feedback during summative clinical assessments. Data were gathered from students by means of semi-structured focus group interviews. Data were transcribed verbatim and coded using Tesch’s eight steps. Two principle themes emerged from the data analysis. Theme 1 unpacked whether an assessor is an ally or foe. Theme 2 focussed on key elements that influence the nature of the feedback process. There were various positive experiences regarding assessor feedback during the summative clinical assessments reported by the participants. However, they were dissatisfied with numerous aspects of assessor feedback during their summative clinical assessments and this subsequently impeded their learning experience. Measures to ensure trustworthiness and ethical research practices governed this research study. Based on the findings, the recommendations include that the higher education institution, clinical supervisors, and radiography students, should utilise feedback as a learning tool for skills development during summative clinical assesssments.
- Full Text:
- Date Issued: 2019
- Authors: Hodgson, Hayley Dianne
- Date: 2019
- Subjects: Medical education , Teacher-student relationships Communication in education Mentoring in education Radiography, Medical -- Digital techniques
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/42296 , vital:36643
- Description: Assessment and feedback are closely interlinked terms. High quality feedback within education and assessment can have a profound influence on learning. Summative clinical assessments and feedback, conducted in clinical training sites, are vital steps in successfully preparing an undergraduate diagnostic radiography student for the desired outcome of a competent, skilled diagnostic radiographer. Feedback has the potential to close the gap between a student’s actual clinical performance and desired clinical performance. Despite the importance of feedback, students across the globe, particularly in the health professions, are dissatisfied with the current feedback systems. Failure to provide effective feedback within the clinical context can be detrimental to patient safety because students have a false impression of their clinical skills and competencies. The aim of the study was to explore and describe the experiences of undergraduate diagnostic radiography students regarding assessor feedback during summative clinical assessments. A qualitative, exploratory, descriptive, and contextual research design was used to gain in-depth knowledge of the experiences of undergraduate diagnostic radiography students regarding assessor feedback during summative clinical assessments. Data were gathered from students by means of semi-structured focus group interviews. Data were transcribed verbatim and coded using Tesch’s eight steps. Two principle themes emerged from the data analysis. Theme 1 unpacked whether an assessor is an ally or foe. Theme 2 focussed on key elements that influence the nature of the feedback process. There were various positive experiences regarding assessor feedback during the summative clinical assessments reported by the participants. However, they were dissatisfied with numerous aspects of assessor feedback during their summative clinical assessments and this subsequently impeded their learning experience. Measures to ensure trustworthiness and ethical research practices governed this research study. Based on the findings, the recommendations include that the higher education institution, clinical supervisors, and radiography students, should utilise feedback as a learning tool for skills development during summative clinical assesssments.
- Full Text:
- Date Issued: 2019
Aspects of the breeding biology of the African penguin on Bird Island, Algoa Bay
- Authors: Ralph, Mark Shaun
- Date: 2008
- Subjects: Penguins -- South Africa -- Conservation , Penguins -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10716 , http://hdl.handle.net/10948/840 , Penguins -- South Africa -- Conservation , Penguins -- South Africa
- Description: It is important to the survival of the Africa Penguin (Spheniscus demersus) population that breeding at the nest site is successful and that large numbers of chicks are fledged into the breeding population. Nest distribution on Bird Island is not random and locality preferences for breeding exist. Although it seems that sufficient area exists on Bird Island for penguin nests, it can hardly be considered as suitable to optimise breeding. During prolonged heat conditions, breeders relocated to nest sites that were sheltered. Nests that were below ground in burrows was the only habitat that did not suffer nest desertion whilst all the other habitat types (including those that were sheltered) experienced 2-3 fold declines in nest numbers. Nests density and the selection of suitable nest sites are significantly influenced by the stage of breeding that the majority of birds are in, yet nests that are shaded, well-ventilated and protected seem to be the most preferred sites for breeding. Adults that attempt to breed are considered then to be in a healthy condition and will usually lay a double clutch (Randell 1983). The frequency of double clutches being laid during the peak breeding attempt was significantly higher compared to the replacement one. Breeding failure was fairly similar to breeding success during the incubation stage for nests with double clutches however, was substantially higher in single clutches. The growth rate of chicks was best fit to the von Bertalanffy growth curve in 90 percent of the cases. The overall growth rate of chicks from double broods was faster than from single broods, however was not significant. A-chicks maitain a high growth rate until they fledged. Yet, the sibling B-chick recorded the lowest growth rate of the successfully fledged chicks and up to until day 30 recorded a similar weight to those chicks that failed to fledge. Contrary to findings of Randall (1983), chicks from single broods delayed fledging, recorded lowest overall growth rates and experienced the greatest weight loss of all groups, yet fledged successfully. In order for chicks to fledge successfully, they needed to obtain a weight of 1060 g before day 30.5 in their growth cycles to avoid death due to startvation later on. Single chicks that are raised from a double cluth, fledged more other than chicks raised from a single clutch. Unfit or ill-adapted breeders that are marginal in the capabilities of raising offspring, already manifest in a small clutch size and offspring unable to obtain adequate weights during the initial stages of growth.
- Full Text:
- Date Issued: 2008
- Authors: Ralph, Mark Shaun
- Date: 2008
- Subjects: Penguins -- South Africa -- Conservation , Penguins -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10716 , http://hdl.handle.net/10948/840 , Penguins -- South Africa -- Conservation , Penguins -- South Africa
- Description: It is important to the survival of the Africa Penguin (Spheniscus demersus) population that breeding at the nest site is successful and that large numbers of chicks are fledged into the breeding population. Nest distribution on Bird Island is not random and locality preferences for breeding exist. Although it seems that sufficient area exists on Bird Island for penguin nests, it can hardly be considered as suitable to optimise breeding. During prolonged heat conditions, breeders relocated to nest sites that were sheltered. Nests that were below ground in burrows was the only habitat that did not suffer nest desertion whilst all the other habitat types (including those that were sheltered) experienced 2-3 fold declines in nest numbers. Nests density and the selection of suitable nest sites are significantly influenced by the stage of breeding that the majority of birds are in, yet nests that are shaded, well-ventilated and protected seem to be the most preferred sites for breeding. Adults that attempt to breed are considered then to be in a healthy condition and will usually lay a double clutch (Randell 1983). The frequency of double clutches being laid during the peak breeding attempt was significantly higher compared to the replacement one. Breeding failure was fairly similar to breeding success during the incubation stage for nests with double clutches however, was substantially higher in single clutches. The growth rate of chicks was best fit to the von Bertalanffy growth curve in 90 percent of the cases. The overall growth rate of chicks from double broods was faster than from single broods, however was not significant. A-chicks maitain a high growth rate until they fledged. Yet, the sibling B-chick recorded the lowest growth rate of the successfully fledged chicks and up to until day 30 recorded a similar weight to those chicks that failed to fledge. Contrary to findings of Randall (1983), chicks from single broods delayed fledging, recorded lowest overall growth rates and experienced the greatest weight loss of all groups, yet fledged successfully. In order for chicks to fledge successfully, they needed to obtain a weight of 1060 g before day 30.5 in their growth cycles to avoid death due to startvation later on. Single chicks that are raised from a double cluth, fledged more other than chicks raised from a single clutch. Unfit or ill-adapted breeders that are marginal in the capabilities of raising offspring, already manifest in a small clutch size and offspring unable to obtain adequate weights during the initial stages of growth.
- Full Text:
- Date Issued: 2008