Implementation of computers in schools: a case study of five schools in the Makana and Somerset East districts
- Authors: Prince, Gilbert Leslie
- Date: 2007
- Subjects: Educational technology , Educational technology -- South Africa -- Eastern Cape , Education, Elementary -- Computer-assisted instruction , Computer-assisted instruction -- South Africa -- Eastern Cape , Computer managed instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1562 , http://hdl.handle.net/10962/d1003444 , Educational technology , Educational technology -- South Africa -- Eastern Cape , Education, Elementary -- Computer-assisted instruction , Computer-assisted instruction -- South Africa -- Eastern Cape , Computer managed instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa -- Eastern Cape
- Description: This case study attempts to explain the implementation of Information Communications Technology (ICT) in primary schools, specifically mentioning the integration of computers into the curriculum. To begin with, the implementation of ICT from an international perspective is explored and subsequently some international and African ICT policies in education are also identified and discussed. Nationally, ICT policies from four provinces in South Africa are examined and analyzed. Provincially, the ICT Projects Coordinator in the Eastern Cape Department of Education (ECDoE) was interviewed to obtain a provincial perspective of ICT in the Eastern Cape. From local schools’ perspective, four primary schools and one secondary school in the Makana and Somerset East Districts were visited and the ICT coordinators at these schools were interviewed. The results reveal that the previously disadvantaged (PD) schools were not utilizing their computers effectively. This is due to a number of factors, including a lack of funds to maintain the computers; unskilled or under skilled teachers in ICT; and under resourced computer facilities. The previously advantaged (PA) schools, on the other hand, have well-resourced computer laboratories, adequate maintenance plans as well as skilled teachers in ICT that enable these schools to effectively integrate the use of computers into the curriculum. Key words: Information communications technology, implementation, integration, previously advantaged, previously disadvantaged, curriculum, primary school, secondary school.
- Full Text:
- Authors: Prince, Gilbert Leslie
- Date: 2007
- Subjects: Educational technology , Educational technology -- South Africa -- Eastern Cape , Education, Elementary -- Computer-assisted instruction , Computer-assisted instruction -- South Africa -- Eastern Cape , Computer managed instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1562 , http://hdl.handle.net/10962/d1003444 , Educational technology , Educational technology -- South Africa -- Eastern Cape , Education, Elementary -- Computer-assisted instruction , Computer-assisted instruction -- South Africa -- Eastern Cape , Computer managed instruction -- South Africa -- Eastern Cape , Internet in education -- South Africa -- Eastern Cape
- Description: This case study attempts to explain the implementation of Information Communications Technology (ICT) in primary schools, specifically mentioning the integration of computers into the curriculum. To begin with, the implementation of ICT from an international perspective is explored and subsequently some international and African ICT policies in education are also identified and discussed. Nationally, ICT policies from four provinces in South Africa are examined and analyzed. Provincially, the ICT Projects Coordinator in the Eastern Cape Department of Education (ECDoE) was interviewed to obtain a provincial perspective of ICT in the Eastern Cape. From local schools’ perspective, four primary schools and one secondary school in the Makana and Somerset East Districts were visited and the ICT coordinators at these schools were interviewed. The results reveal that the previously disadvantaged (PD) schools were not utilizing their computers effectively. This is due to a number of factors, including a lack of funds to maintain the computers; unskilled or under skilled teachers in ICT; and under resourced computer facilities. The previously advantaged (PA) schools, on the other hand, have well-resourced computer laboratories, adequate maintenance plans as well as skilled teachers in ICT that enable these schools to effectively integrate the use of computers into the curriculum. Key words: Information communications technology, implementation, integration, previously advantaged, previously disadvantaged, curriculum, primary school, secondary school.
- Full Text:
Implementation of learner-centred education by Grade 4 BETD in-service teachers in selected Namibia schools
- Authors: Amakali, Amram
- Date: 2007
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1849 , http://hdl.handle.net/10962/d1004457
- Description: Before independence Namibia's education system was predominantly teacher-centred. Soon after its independence Namibia embarked on education restructuring and transformation. A new education system, leamer-centred education, was introduced to cater for the needs of all Namibian learners. It was seen as an effective antidote to the stifling teacher-centred practices of the previous education system. A new programme, the Basic Education Teacher Diploma (BETD) was introduced to prepare teachers to teach in a leamer-centred approach. Research has, however, indicated that many Namibian teachers have a somewhat shallow or naIve understanding oflearner-centred education. This small-scale case study, conducted in Oshikoto region, focuses on two Grade 4 teachers. The study examined the two teachers ' perceptions and experiences oflearnercentred education and the teaching strategies they use to develop learners' understanding. The study uses a qualitative approach in its exploration of teachers ' lived experiences of becoming learner-centred. The data emerging from this case study identify a number of misconceptions and understandings of leamer-centred education and its implementation. The findings suggest that teachers ' misconceptions are caused by a lack of deep understanding about the epistemology and theory of learning which underpins Namibia's reform policies and principles.
- Full Text:
- Authors: Amakali, Amram
- Date: 2007
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1849 , http://hdl.handle.net/10962/d1004457
- Description: Before independence Namibia's education system was predominantly teacher-centred. Soon after its independence Namibia embarked on education restructuring and transformation. A new education system, leamer-centred education, was introduced to cater for the needs of all Namibian learners. It was seen as an effective antidote to the stifling teacher-centred practices of the previous education system. A new programme, the Basic Education Teacher Diploma (BETD) was introduced to prepare teachers to teach in a leamer-centred approach. Research has, however, indicated that many Namibian teachers have a somewhat shallow or naIve understanding oflearner-centred education. This small-scale case study, conducted in Oshikoto region, focuses on two Grade 4 teachers. The study examined the two teachers ' perceptions and experiences oflearnercentred education and the teaching strategies they use to develop learners' understanding. The study uses a qualitative approach in its exploration of teachers ' lived experiences of becoming learner-centred. The data emerging from this case study identify a number of misconceptions and understandings of leamer-centred education and its implementation. The findings suggest that teachers ' misconceptions are caused by a lack of deep understanding about the epistemology and theory of learning which underpins Namibia's reform policies and principles.
- Full Text:
Implementation tensions and challenges in donor funded curriculum projects: a case analysis of environmental and population education projects in Lesotho
- Monaheng, Nkaiseng ̕Mamotšelisi
- Authors: Monaheng, Nkaiseng ̕Mamotšelisi
- Date: 2007
- Subjects: National Curriculum Development Centre (Lesotho) Curriculum planning -- Lesotho Environmental education -- Lesotho Economic assistance -- Lesotho Technical assistance -- Lesotho Sustainable development -- Lesotho
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1568 , http://hdl.handle.net/10962/d1003450
- Description: This study aims to capture the challenges and tensions that arise in donor funded curriculum projects in Lesotho. Through an interpretive case study research design I investigated these challenges and tensions in two projects relevant to Education for Sustainable Development, namely the Lesotho Environmental Support Project (LEESP) and the Population/Family Education (POP/FLE) projects which are donor funded curriculum projects funded by DANIDA and UNFPA respectively. A review of donor funded curriculum projects in the field of environmental education/Education for Sustainable Development was undertaken to provide background and a theoretical context for the study. It highlighted different challenges and implementation tensions experienced by other similar projects in other countries. At the heart of such projects lies a particular political economy, which is based on development assistance to poor countries. Such development assistance is constructed around concepts of need, participation and innovation, and donor-recipient relationships. It is structured around a system of governance and management that normally uses logical framework planning as its main methodology. This political economy has shaped the two donor funded projects that were considered in this study, and has shaped many of the tensions and challenges identified in the study. To investigate the two projects, data for this study was generated through in-depth interviews, document analysis and focus group interviews, with people who had been involved with the projects at the national level. The data generation process did not involve the schools where the projects were ultimately implemented, as it was seeking to identify how local institutions such as the National Curriculum Development Centre could support better synergies between donor funded initiatives and the local context. The findings of the study revealed the ambivalent nature of donor initiatives, and identified that the political economy and donor-recipient relations influence the projects. Aspects such as the design and management of projects, the processes associated with introducing innovation in educational ideas and paradigms, pedagogical issues, and staff contributions and ownership were identified as some of the key tensions that existed in the projects. Other factors such as poor capacity levels of local staff, non-alignment with existing structures, inadequate sustainability mechanisms and the difficulty of the envisaged integration of new paradigm thinking (methods and approaches) into the existing curriculum framework were also significant tensions, given the positivist history of the Lesotho curriculum. The study recommends the need to establish mechanisms for working with donors to tackle the tensions that arise in such projects within longer-term donor assistance. It proposes that government should expedite the development of policy on donor coordination. Both donors and the NCDC need to put mechanisms in place to allow for debate and discussions on innovations brought in by the donors in relation to local needs. The study further recommends that in cases where more than one donor exists, the NCDC and the donors should work towards developing synergies between the different initiatives to avoid duplication and overlap. Finally, there is a need for projects to use bottom-up approaches for the design and formulation of projects to ensure ownership.
- Full Text:
- Authors: Monaheng, Nkaiseng ̕Mamotšelisi
- Date: 2007
- Subjects: National Curriculum Development Centre (Lesotho) Curriculum planning -- Lesotho Environmental education -- Lesotho Economic assistance -- Lesotho Technical assistance -- Lesotho Sustainable development -- Lesotho
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1568 , http://hdl.handle.net/10962/d1003450
- Description: This study aims to capture the challenges and tensions that arise in donor funded curriculum projects in Lesotho. Through an interpretive case study research design I investigated these challenges and tensions in two projects relevant to Education for Sustainable Development, namely the Lesotho Environmental Support Project (LEESP) and the Population/Family Education (POP/FLE) projects which are donor funded curriculum projects funded by DANIDA and UNFPA respectively. A review of donor funded curriculum projects in the field of environmental education/Education for Sustainable Development was undertaken to provide background and a theoretical context for the study. It highlighted different challenges and implementation tensions experienced by other similar projects in other countries. At the heart of such projects lies a particular political economy, which is based on development assistance to poor countries. Such development assistance is constructed around concepts of need, participation and innovation, and donor-recipient relationships. It is structured around a system of governance and management that normally uses logical framework planning as its main methodology. This political economy has shaped the two donor funded projects that were considered in this study, and has shaped many of the tensions and challenges identified in the study. To investigate the two projects, data for this study was generated through in-depth interviews, document analysis and focus group interviews, with people who had been involved with the projects at the national level. The data generation process did not involve the schools where the projects were ultimately implemented, as it was seeking to identify how local institutions such as the National Curriculum Development Centre could support better synergies between donor funded initiatives and the local context. The findings of the study revealed the ambivalent nature of donor initiatives, and identified that the political economy and donor-recipient relations influence the projects. Aspects such as the design and management of projects, the processes associated with introducing innovation in educational ideas and paradigms, pedagogical issues, and staff contributions and ownership were identified as some of the key tensions that existed in the projects. Other factors such as poor capacity levels of local staff, non-alignment with existing structures, inadequate sustainability mechanisms and the difficulty of the envisaged integration of new paradigm thinking (methods and approaches) into the existing curriculum framework were also significant tensions, given the positivist history of the Lesotho curriculum. The study recommends the need to establish mechanisms for working with donors to tackle the tensions that arise in such projects within longer-term donor assistance. It proposes that government should expedite the development of policy on donor coordination. Both donors and the NCDC need to put mechanisms in place to allow for debate and discussions on innovations brought in by the donors in relation to local needs. The study further recommends that in cases where more than one donor exists, the NCDC and the donors should work towards developing synergies between the different initiatives to avoid duplication and overlap. Finally, there is a need for projects to use bottom-up approaches for the design and formulation of projects to ensure ownership.
- Full Text:
Implementing innovative assessment methods in undergraduate Mathematics
- Authors: Matutu, Phethiwe P
- Date: 2007
- Language: English
- Type: Text
- Identifier: vital:6779 , http://hdl.handle.net/10962/d1006947
- Description: The following challenges associated with teaching undergraduate Mathematics will be discussed: Negative attitudes of students to Mathematics, Student’s reluctance to practise Mathematics, and surface learning. Some (or all) of the ways in which assessment can be used to address these challenges will be discussed. If used strategically assessment methods/tasks can enhance the teaching and learning of mathematics. Some of the unique challenges that we as lecturers face in teaching mathematics can be remedied by selecting appropriate assessment techniques/tasks. Using the tutorial time fruitfully is one of the challenging aspects in teaching mathematics. Not taking tutorials and other formative assessments seriously is not an uncommon student attitude in higher education contexts. Students who are pressured for time often do not see the immediate value of formative assessment or of discussion as a useful learning activity. A collection of case studies which clearly document what has been tried in different contexts is very useful in mathematics as this information is limited in the South African higher education sector. An innovative assessment method (peer-assessment) which was introduced for a Linear Algebra second year course at Rhodes University (South Africa) will be presented: The implementation method, purpose of introducing the assessment method, its advantages, and disadvantages will be examined. A reflection on the assessment method and concluding remarks will be provided.
- Full Text:
- Authors: Matutu, Phethiwe P
- Date: 2007
- Language: English
- Type: Text
- Identifier: vital:6779 , http://hdl.handle.net/10962/d1006947
- Description: The following challenges associated with teaching undergraduate Mathematics will be discussed: Negative attitudes of students to Mathematics, Student’s reluctance to practise Mathematics, and surface learning. Some (or all) of the ways in which assessment can be used to address these challenges will be discussed. If used strategically assessment methods/tasks can enhance the teaching and learning of mathematics. Some of the unique challenges that we as lecturers face in teaching mathematics can be remedied by selecting appropriate assessment techniques/tasks. Using the tutorial time fruitfully is one of the challenging aspects in teaching mathematics. Not taking tutorials and other formative assessments seriously is not an uncommon student attitude in higher education contexts. Students who are pressured for time often do not see the immediate value of formative assessment or of discussion as a useful learning activity. A collection of case studies which clearly document what has been tried in different contexts is very useful in mathematics as this information is limited in the South African higher education sector. An innovative assessment method (peer-assessment) which was introduced for a Linear Algebra second year course at Rhodes University (South Africa) will be presented: The implementation method, purpose of introducing the assessment method, its advantages, and disadvantages will be examined. A reflection on the assessment method and concluding remarks will be provided.
- Full Text:
Implications of life history for genetic structure and migration rates of southern African coastal invertebrates: planktonic, abbreviated and direct development
- Teske, Peter R, Papadopoulos, Isabelle, Zardi, Gerardo I, McQuaid, Christopher D, Edkins, M T, Griffiths, Charles L, Barker, Nigel P
- Authors: Teske, Peter R , Papadopoulos, Isabelle , Zardi, Gerardo I , McQuaid, Christopher D , Edkins, M T , Griffiths, Charles L , Barker, Nigel P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445447 , vital:74388 , https://doi.org/10.1007/s00227-007-0724-y
- Description: The amount of genetic structure in marine invertebrates is often thought to be negatively correlated with larval duration. However, larval retention may increase genetic structure in species with long-lived planktonic larvae, and rafting provides a means of dispersal for species that lack a larval dispersal phase. We compared genetic structure, demographic histories and levels of gene flow of regional lineages (in most cases defined by biogeographic region) of five southern African coastal invertebrates with three main types of larval development: (1) dispersal by long-lived planktonic larvae (mudprawn Upogebia africana and brown mussel Perna perna), (2) abbreviated larval development (crown crab Hymenosoma orbiculare) and (3) direct development (estuarine isopod Exosphaeroma hylecoetes and estuarine cumacean Iphinoe truncata). We hypothesized that H. orbiculare, having abbreviated larval development, would employ a strategy of larval retention, resulting in genetic structure comparable to that of the direct developers rather than the planktonic dispersers.
- Full Text:
- Authors: Teske, Peter R , Papadopoulos, Isabelle , Zardi, Gerardo I , McQuaid, Christopher D , Edkins, M T , Griffiths, Charles L , Barker, Nigel P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445447 , vital:74388 , https://doi.org/10.1007/s00227-007-0724-y
- Description: The amount of genetic structure in marine invertebrates is often thought to be negatively correlated with larval duration. However, larval retention may increase genetic structure in species with long-lived planktonic larvae, and rafting provides a means of dispersal for species that lack a larval dispersal phase. We compared genetic structure, demographic histories and levels of gene flow of regional lineages (in most cases defined by biogeographic region) of five southern African coastal invertebrates with three main types of larval development: (1) dispersal by long-lived planktonic larvae (mudprawn Upogebia africana and brown mussel Perna perna), (2) abbreviated larval development (crown crab Hymenosoma orbiculare) and (3) direct development (estuarine isopod Exosphaeroma hylecoetes and estuarine cumacean Iphinoe truncata). We hypothesized that H. orbiculare, having abbreviated larval development, would employ a strategy of larval retention, resulting in genetic structure comparable to that of the direct developers rather than the planktonic dispersers.
- Full Text:
Inetvis: a graphical aid for the detection and visualisation of network scans
- Irwin, Barry V W, van Riel, Jean-Pierre
- Authors: Irwin, Barry V W , van Riel, Jean-Pierre
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430381 , vital:72687 , https://www.cs.ru.ac.za/research/g02V2468/publications/Irwin-VizSEC2007_draft.pdf
- Description: This paper presents an investigative analysis of network scans and scan detection algorithms. Visualisation is employed to review network telescope traffic and identify incidents of scan activity. Some of the identified phenomena appear to be novel forms of host discovery. The scan detection algorithms of Snort and Bro are critiqued by comparing the visualised scans with alert output. Where human assessment disa-grees with the alert output, explanations are sought after by analysing the detection algorithms. The algorithms of the Snort and Bro intrusion detection systems are based on counting unique connection attempts to destination addresses and ports. For Snort, notable false positive and false negative cases result due to a grossly oversimplified method of counting unique destination addresses and ports.
- Full Text:
- Authors: Irwin, Barry V W , van Riel, Jean-Pierre
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430381 , vital:72687 , https://www.cs.ru.ac.za/research/g02V2468/publications/Irwin-VizSEC2007_draft.pdf
- Description: This paper presents an investigative analysis of network scans and scan detection algorithms. Visualisation is employed to review network telescope traffic and identify incidents of scan activity. Some of the identified phenomena appear to be novel forms of host discovery. The scan detection algorithms of Snort and Bro are critiqued by comparing the visualised scans with alert output. Where human assessment disa-grees with the alert output, explanations are sought after by analysing the detection algorithms. The algorithms of the Snort and Bro intrusion detection systems are based on counting unique connection attempts to destination addresses and ports. For Snort, notable false positive and false negative cases result due to a grossly oversimplified method of counting unique destination addresses and ports.
- Full Text:
Inflation targeting and the Fisher effect in South Africa: An empirical investigation
- Mitchell-Innes, Henry A, Aziakpono, Meshach J, Faure, Alexander P
- Authors: Mitchell-Innes, Henry A , Aziakpono, Meshach J , Faure, Alexander P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469786 , vital:77294 , https://doi.org/10.1111/j.1813-6982.2007.00143.x
- Description: The paper analyses the relationship between expected inflation and nominal interest rates during a period of inflation targeting in South Africa, i.e. from 2000 to 2005. Specifically, it investigates the Fisher hypothesis that nominal interest rates move one‐to‐one with expected inflation, leaving the real interest rate unaffected. The analysis distinguishes between a short‐run Fisher effect and a long‐run Fisher effect. Using cointegration and error correction models (for monthly data for the period April 2000 to July 2005), it was found that the short‐run Fisher hypothesis did not hold during the relevant period under the inflation targeting monetary policy framework in South Africa. This is attributed to a combination of the South African Reserve Bank's (SARB) control over short‐term interest rates and the effects of the monetary transmission mechanism. The long‐run Fisher hypothesis could not be confirmed in its strictest form: while changes in inflation expectations move in the same direction as the nominal long‐term interest rate. This suggests that monetary policy has an influence on the real long-term interest rate, which has positive implications for general economic activity, thus confirming the credibility of the inflation targeting framework.
- Full Text:
- Authors: Mitchell-Innes, Henry A , Aziakpono, Meshach J , Faure, Alexander P
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/469786 , vital:77294 , https://doi.org/10.1111/j.1813-6982.2007.00143.x
- Description: The paper analyses the relationship between expected inflation and nominal interest rates during a period of inflation targeting in South Africa, i.e. from 2000 to 2005. Specifically, it investigates the Fisher hypothesis that nominal interest rates move one‐to‐one with expected inflation, leaving the real interest rate unaffected. The analysis distinguishes between a short‐run Fisher effect and a long‐run Fisher effect. Using cointegration and error correction models (for monthly data for the period April 2000 to July 2005), it was found that the short‐run Fisher hypothesis did not hold during the relevant period under the inflation targeting monetary policy framework in South Africa. This is attributed to a combination of the South African Reserve Bank's (SARB) control over short‐term interest rates and the effects of the monetary transmission mechanism. The long‐run Fisher hypothesis could not be confirmed in its strictest form: while changes in inflation expectations move in the same direction as the nominal long‐term interest rate. This suggests that monetary policy has an influence on the real long-term interest rate, which has positive implications for general economic activity, thus confirming the credibility of the inflation targeting framework.
- Full Text:
Insights into the surface and redox properties of single-walled carbon nanotube—cobalt (II) tetra-aminophthalocyanine self-assembled on gold electrode
- Ozoemena, Kenneth I, Nyokong, Tebello, Nkosi, Duduzile, Chambrier, Isabelle, Cook, Michael J
- Authors: Ozoemena, Kenneth I , Nyokong, Tebello , Nkosi, Duduzile , Chambrier, Isabelle , Cook, Michael J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281258 , vital:55707 , xlink:href="https://doi.org/10.1016/j.electacta.2006.11.039"
- Description: This paper describes for the first time the electrochemical properties of redox-active self-assembled films of single-walled carbon nanotubes (SWCNTs) coordinated to cobalt(II)tetra-aminophthalocyanine (CoTAPc) by sequential self-assembly onto a preformed aminoethanethiol (AET) self-assembled monolayer (SAM) on a gold electrode. Both redox-active SAMs (Au-AET-SWCNT and Au-AET-SWCNT-CoTAPc) exhibited reversible electrochemistry in aqueous (phosphate buffer) solution. X-ray photoelectron spectroscopy (XPS) confirmed the appearance on the gold surface of the various elements found on the SAMs. Atomic force microscopy (AFM) images prove, corroborating the estimated electrochemical surface concentrations, that these SAMs lie normal to the gold surface. Electrochemical impedance spectroscopy (EIS) analyses in the presence of [Fe(CN)6]3−/4− as a redox probe revealed that the Au-AET-SWCNT-CoTAPc showed much lower (∼10 times) electron-transfer resistance (Ret) and much higher (∼10 times) apparent electron-transfer rate constant (kapp) compared to the Au-AET-SWCNT SAM. Interestingly, a preliminary electrocatalytic investigation showed that both SAMs exhibit comparable electrocatalytic responses towards the detection of dopamine in pH 7.4 phosphate buffer solutions (PBS). The electrochemical studies (cyclic voltammetry (CV) and EIS) prove that SWCNT greatly improves the electronic communication between CoTAPc and the Au electrode surface.
- Full Text:
- Authors: Ozoemena, Kenneth I , Nyokong, Tebello , Nkosi, Duduzile , Chambrier, Isabelle , Cook, Michael J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281258 , vital:55707 , xlink:href="https://doi.org/10.1016/j.electacta.2006.11.039"
- Description: This paper describes for the first time the electrochemical properties of redox-active self-assembled films of single-walled carbon nanotubes (SWCNTs) coordinated to cobalt(II)tetra-aminophthalocyanine (CoTAPc) by sequential self-assembly onto a preformed aminoethanethiol (AET) self-assembled monolayer (SAM) on a gold electrode. Both redox-active SAMs (Au-AET-SWCNT and Au-AET-SWCNT-CoTAPc) exhibited reversible electrochemistry in aqueous (phosphate buffer) solution. X-ray photoelectron spectroscopy (XPS) confirmed the appearance on the gold surface of the various elements found on the SAMs. Atomic force microscopy (AFM) images prove, corroborating the estimated electrochemical surface concentrations, that these SAMs lie normal to the gold surface. Electrochemical impedance spectroscopy (EIS) analyses in the presence of [Fe(CN)6]3−/4− as a redox probe revealed that the Au-AET-SWCNT-CoTAPc showed much lower (∼10 times) electron-transfer resistance (Ret) and much higher (∼10 times) apparent electron-transfer rate constant (kapp) compared to the Au-AET-SWCNT SAM. Interestingly, a preliminary electrocatalytic investigation showed that both SAMs exhibit comparable electrocatalytic responses towards the detection of dopamine in pH 7.4 phosphate buffer solutions (PBS). The electrochemical studies (cyclic voltammetry (CV) and EIS) prove that SWCNT greatly improves the electronic communication between CoTAPc and the Au electrode surface.
- Full Text:
Intermediating Africa:
- Authors: Garman, Anthea
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158806 , vital:40230 , https://hdl.handle.net/10520/EJC144693
- Description: In July, Vanity Fair, based in New York, did a unique special edition. Editor Graydon Carter explained how it came about: "Earlier this year, Mark Dowley, a marketing polymath at the Endeavour talent agency who has been involved with Bono's (Red) campaign from the start, called to inquire if I would be interested in having him guest edit an issue of the magazine. Interested? I'll say!".
- Full Text:
- Authors: Garman, Anthea
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158806 , vital:40230 , https://hdl.handle.net/10520/EJC144693
- Description: In July, Vanity Fair, based in New York, did a unique special edition. Editor Graydon Carter explained how it came about: "Earlier this year, Mark Dowley, a marketing polymath at the Endeavour talent agency who has been involved with Bono's (Red) campaign from the start, called to inquire if I would be interested in having him guest edit an issue of the magazine. Interested? I'll say!".
- Full Text:
International trade and environmental disputes : an analysis of Article XX of the General Agreement on Tariffs and Trade (1994) and environmental policies of the developing and developed world
- Authors: Manjoro, Faith Tendayi
- Date: 2007
- Subjects: World Trade Organization General Agreement on Tariffs and Trade (Organization) Environmental protection Environmental degradation Free trade -- Environmental aspects Foreign trade regulation International trade
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3713 , http://hdl.handle.net/10962/d1007444
- Description: A major problem emanating from the trade/environment conflict is the use of trade measures, such as restrictions and sanctions, as tools for environmental protection. Proponents of free trade argue that the use of these measures is tantamount to abuse of environmental standards for protectionist ends. This is particularly so if the imposition of the standard amounts to a unilateral act which blocks the entry of a specified product into the market of another member state for reasons other than environmental protection. Environmentalists at the same time argue that free trade will lead to environmental degradation and therefore advocate for the use of trade-restrictive measures to safeguard against the destruction of the environment. The GATT has proved problematic when it comes to the resolution of trade/environment conflicts. The GATT aims at trade liberalisation yet most environmental policies are enforced through trade-restrictive devices like quotas and licences. Article XX of the GATT is anomalous: it does not explicitly mention the environment, yet member states rely on it as an environmental protection clause. This thesis discusses the various issues emanating from the trade/environmental debate. The history of Article XX is reviewed and the issues that arise in the adjudication of Articles XX (b) and (g) in a trade/environment context are analysed in light of the decisions by the GATTIWTO dispute settlement bodies. The role played by Multilateral Environmental Agreements (MEAs) in protecting the environment is discussed. However, the relationship between MEAs and the WTO is also scrutinised as these rule-making bodies often come into conflict: firstly, because they serve two differing interests - on the one hand, MEAs allow for the use of trade restrictive measures in environmental agreements and on the other, the WTO calls for unrestricted trade unless exceptional circumstances exist; and secondly, member states that are party to both the WTO and MEAs are often forced to subscribe to international trade rules that are incompatible with those in environmental agreements. The trade/environmental debate is important to both the developed and developing worlds. The developed world is in favour of environmental policies which protect the environment from degradation. On the other hand, the developing world is in desperate need of the benefits of trade liberalisation so as to cater for high unemployment rates and poor economic growth. The question thus arises as to whether, when environmental issues are promoted, developing countries will not suffer at the expense of developed nations which may engage in protectionist measures under the pretext of environmental conservation. The divide between developed and developing countries is illustrated in Chapter 5 through case studies on coal mining in the USA and South Africa. The conclusion reached is that total co-operation is essential between developed and developing states for success in safeguarding the environment from degradation. Accordingly, the trade/environmental debate cannot be isolated from the conflicting approaches in developed and developing countries. The conclusions in the final chapter seek to strike a balance between trade liberalisation and environmental protection. Recommendations are made on how the trade/environmental challenges could be dealt with and the regulation of trade restrictive devices to exclude, or at least limit, protectionism.
- Full Text:
- Authors: Manjoro, Faith Tendayi
- Date: 2007
- Subjects: World Trade Organization General Agreement on Tariffs and Trade (Organization) Environmental protection Environmental degradation Free trade -- Environmental aspects Foreign trade regulation International trade
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3713 , http://hdl.handle.net/10962/d1007444
- Description: A major problem emanating from the trade/environment conflict is the use of trade measures, such as restrictions and sanctions, as tools for environmental protection. Proponents of free trade argue that the use of these measures is tantamount to abuse of environmental standards for protectionist ends. This is particularly so if the imposition of the standard amounts to a unilateral act which blocks the entry of a specified product into the market of another member state for reasons other than environmental protection. Environmentalists at the same time argue that free trade will lead to environmental degradation and therefore advocate for the use of trade-restrictive measures to safeguard against the destruction of the environment. The GATT has proved problematic when it comes to the resolution of trade/environment conflicts. The GATT aims at trade liberalisation yet most environmental policies are enforced through trade-restrictive devices like quotas and licences. Article XX of the GATT is anomalous: it does not explicitly mention the environment, yet member states rely on it as an environmental protection clause. This thesis discusses the various issues emanating from the trade/environmental debate. The history of Article XX is reviewed and the issues that arise in the adjudication of Articles XX (b) and (g) in a trade/environment context are analysed in light of the decisions by the GATTIWTO dispute settlement bodies. The role played by Multilateral Environmental Agreements (MEAs) in protecting the environment is discussed. However, the relationship between MEAs and the WTO is also scrutinised as these rule-making bodies often come into conflict: firstly, because they serve two differing interests - on the one hand, MEAs allow for the use of trade restrictive measures in environmental agreements and on the other, the WTO calls for unrestricted trade unless exceptional circumstances exist; and secondly, member states that are party to both the WTO and MEAs are often forced to subscribe to international trade rules that are incompatible with those in environmental agreements. The trade/environmental debate is important to both the developed and developing worlds. The developed world is in favour of environmental policies which protect the environment from degradation. On the other hand, the developing world is in desperate need of the benefits of trade liberalisation so as to cater for high unemployment rates and poor economic growth. The question thus arises as to whether, when environmental issues are promoted, developing countries will not suffer at the expense of developed nations which may engage in protectionist measures under the pretext of environmental conservation. The divide between developed and developing countries is illustrated in Chapter 5 through case studies on coal mining in the USA and South Africa. The conclusion reached is that total co-operation is essential between developed and developing states for success in safeguarding the environment from degradation. Accordingly, the trade/environmental debate cannot be isolated from the conflicting approaches in developed and developing countries. The conclusions in the final chapter seek to strike a balance between trade liberalisation and environmental protection. Recommendations are made on how the trade/environmental challenges could be dealt with and the regulation of trade restrictive devices to exclude, or at least limit, protectionism.
- Full Text:
Investigating grade 10 geography teachers' implementation of a learner-centred approach in selected Namibian schools
- Authors: Angula, Adelheid
- Date: 2007
- Subjects: Geography -- Study and teaching (Secondary) -- Namibia Student-centered learning -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1851 , http://hdl.handle.net/10962/d1004459
- Description: Geography, more than other subjects in the curriculum, plays a central role in general education in equipping learners with skills and competencies needed for modern living and global citizenship. A learner-centred education in Namibia was adopted to provide more opportunities for learners to develop the required skills and competencies irrespective of their different cultural background. This small-scale case study investigated three Grade 10 geography teachers' understanding and implementation ofa learner-centred approach to gain insights into how leamer-centred education is being implemented in the context of Geography. The research design adopted a qualitative approach within an interpretative orientation. Data were collected through interviews, classroom observations and documentary analysis. The research was conducted at three selected schools in Oshikoto Region with three Grade 10 geography teachers The findings revealed, firstly, that teachers have a limited understanding of the key ideas ofLCE, such as, prior knowledge, role of questioning, and social interaction in learning; use of resources and the types of assessment activities which comply with the aims of LCE. Seconclly, the findings revealed that the policy documents, such as syllabuses, that are being used by the participants are not in line with the tenets ofLCE. Thirdly, teachers appeared to have limited subject knowledge, as revealed by their lack of understanding of how to translate the aims and assessment objectives into their daily lessons. The study therefore raises some possibilities for improving the implementation of LCE in the selected schools if the gaps as identified by this study are reduced.
- Full Text:
- Authors: Angula, Adelheid
- Date: 2007
- Subjects: Geography -- Study and teaching (Secondary) -- Namibia Student-centered learning -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1851 , http://hdl.handle.net/10962/d1004459
- Description: Geography, more than other subjects in the curriculum, plays a central role in general education in equipping learners with skills and competencies needed for modern living and global citizenship. A learner-centred education in Namibia was adopted to provide more opportunities for learners to develop the required skills and competencies irrespective of their different cultural background. This small-scale case study investigated three Grade 10 geography teachers' understanding and implementation ofa learner-centred approach to gain insights into how leamer-centred education is being implemented in the context of Geography. The research design adopted a qualitative approach within an interpretative orientation. Data were collected through interviews, classroom observations and documentary analysis. The research was conducted at three selected schools in Oshikoto Region with three Grade 10 geography teachers The findings revealed, firstly, that teachers have a limited understanding of the key ideas ofLCE, such as, prior knowledge, role of questioning, and social interaction in learning; use of resources and the types of assessment activities which comply with the aims of LCE. Seconclly, the findings revealed that the policy documents, such as syllabuses, that are being used by the participants are not in line with the tenets ofLCE. Thirdly, teachers appeared to have limited subject knowledge, as revealed by their lack of understanding of how to translate the aims and assessment objectives into their daily lessons. The study therefore raises some possibilities for improving the implementation of LCE in the selected schools if the gaps as identified by this study are reduced.
- Full Text:
Investigating the effect of Glomus etunicatum colonization on structure and phloem transport in roots of Eragrostis curvula (Umgeni)
- Authors: Skinner, Amy
- Date: 2007
- Subjects: Glomus (Fungi) , Phloem , Plant translocation , Weeping lovegrass , Vesicular-arbuscular mycorrhizas , Mycorrhizal fungi , Mycorrhizas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4227 , http://hdl.handle.net/10962/d1003796 , Glomus (Fungi) , Phloem , Plant translocation , Weeping lovegrass , Vesicular-arbuscular mycorrhizas , Mycorrhizal fungi , Mycorrhizas
- Description: The symbiotic unit of an arbuscular mycorrhizal fungus and its host is able toachieve and maintain far higher inflow of nutrients than non-mycorrhizal roots. The colonization strategy of the mycobiont within the plant is intrinsic to the symbiosis with respect to both structural adaptations and nutrient exchange. An investigation into the effect of Glomus etunicatum colonization on the structure and phloem transport in Eragrostis curvula (Umgeni) allowed for greater insight into the dynamic of the symbiosis. The combined use of stains (such as Trypan Blue, Chlorazol Black, Safranin and Fast Green), and techniques, (such as freeze-microtome transverse sectioning and permanent slide preparations) contributed to a successful general observation of an intermediate colonization strategy using light microscopy methods. However, clarity into structural detail of mycorrhizal forms required electron microscopy studies. The SEM method used with freeze fracture was a relatively quick and simple method allowing for the observation of surface and internal features. The TEM method allowed for highresolution images providing insight into the variations in the apoplasmic compartmental form, and how this may relate to the function of the symbiosis with regard to fungal coils or arbuscules. The apoplasmic nature of mycorrhizas was substantiated and no symplasmic connections were found between symbionts. Fluorescence studies demonstrated that 5,6-carboxyfluorescein was transported through the phloem into the roots of E. curvula, but remained predominantly in the root phloem. Unloading only occurred in optimal nutrient exchange areas of meristimatic lateral or apical growth regions. It was not possible, using fluorescence techniques and related equipment available, to conclusively establish if there were symplasmic connections between the mycobiont and its host or if bidirectional transfer of nutrients occurred at the same interface.
- Full Text:
- Authors: Skinner, Amy
- Date: 2007
- Subjects: Glomus (Fungi) , Phloem , Plant translocation , Weeping lovegrass , Vesicular-arbuscular mycorrhizas , Mycorrhizal fungi , Mycorrhizas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4227 , http://hdl.handle.net/10962/d1003796 , Glomus (Fungi) , Phloem , Plant translocation , Weeping lovegrass , Vesicular-arbuscular mycorrhizas , Mycorrhizal fungi , Mycorrhizas
- Description: The symbiotic unit of an arbuscular mycorrhizal fungus and its host is able toachieve and maintain far higher inflow of nutrients than non-mycorrhizal roots. The colonization strategy of the mycobiont within the plant is intrinsic to the symbiosis with respect to both structural adaptations and nutrient exchange. An investigation into the effect of Glomus etunicatum colonization on the structure and phloem transport in Eragrostis curvula (Umgeni) allowed for greater insight into the dynamic of the symbiosis. The combined use of stains (such as Trypan Blue, Chlorazol Black, Safranin and Fast Green), and techniques, (such as freeze-microtome transverse sectioning and permanent slide preparations) contributed to a successful general observation of an intermediate colonization strategy using light microscopy methods. However, clarity into structural detail of mycorrhizal forms required electron microscopy studies. The SEM method used with freeze fracture was a relatively quick and simple method allowing for the observation of surface and internal features. The TEM method allowed for highresolution images providing insight into the variations in the apoplasmic compartmental form, and how this may relate to the function of the symbiosis with regard to fungal coils or arbuscules. The apoplasmic nature of mycorrhizas was substantiated and no symplasmic connections were found between symbionts. Fluorescence studies demonstrated that 5,6-carboxyfluorescein was transported through the phloem into the roots of E. curvula, but remained predominantly in the root phloem. Unloading only occurred in optimal nutrient exchange areas of meristimatic lateral or apical growth regions. It was not possible, using fluorescence techniques and related equipment available, to conclusively establish if there were symplasmic connections between the mycobiont and its host or if bidirectional transfer of nutrients occurred at the same interface.
- Full Text:
Investigating the implementation of continuous assessment at the lower primary phase in a Namibian school
- Authors: Hamukonda, Paulina
- Date: 2007
- Subjects: Education, Elementary -- Namibia Educational tests and measurements -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1592 , http://hdl.handle.net/10962/d1003474
- Description: Many Namibian teachers experience difficulties in actualising the principles of learner-centred education, one of which being continuous assessment. Continuous assessment serves important formative purposes. That is, it can inform education stakeholders and help improve learners’ progress in the teaching and learning environment. Although a great deal is known about continuous assessment in general, not much is yet known about how Namibian lower primary teachers actually understand and implement continuous assessment in the classroom. This study investigates the assessment practices of three Grade Three teachers in a school in Oshana Region of Namibia. The study found that although the teachers who participated in the investigation have a reasonably sound knowledge of continuous assessment in theory, they lack implementation skills. They were unable to effectively transfer what they know to what they actually do. This study found that as much as training of teachers is important, the ongoing professional development of teachers is more appropriate for enhancing a complex understanding of issues related to learner-centred education that will help them to manage continuous assessment more effectively.
- Full Text:
- Authors: Hamukonda, Paulina
- Date: 2007
- Subjects: Education, Elementary -- Namibia Educational tests and measurements -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1592 , http://hdl.handle.net/10962/d1003474
- Description: Many Namibian teachers experience difficulties in actualising the principles of learner-centred education, one of which being continuous assessment. Continuous assessment serves important formative purposes. That is, it can inform education stakeholders and help improve learners’ progress in the teaching and learning environment. Although a great deal is known about continuous assessment in general, not much is yet known about how Namibian lower primary teachers actually understand and implement continuous assessment in the classroom. This study investigates the assessment practices of three Grade Three teachers in a school in Oshana Region of Namibia. The study found that although the teachers who participated in the investigation have a reasonably sound knowledge of continuous assessment in theory, they lack implementation skills. They were unable to effectively transfer what they know to what they actually do. This study found that as much as training of teachers is important, the ongoing professional development of teachers is more appropriate for enhancing a complex understanding of issues related to learner-centred education that will help them to manage continuous assessment more effectively.
- Full Text:
Investigating the implementation of continuous assessment by grade 7 Social Studies teachers in the Oshana education region
- Authors: Matheus, Hilya
- Date: 2007
- Subjects: Educational tests and measurements -- Namibia Social sciences -- Study and teaching (Elementary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1593 , http://hdl.handle.net/10962/d1003475
- Description: Since independence in 1990, Namibia’s Ministry of Education Sport and Culture has focused on curriculum and assessment reforms. The introduction of Continuous Assessment (CA) for appraising learners’ achievement was considered to be a very important aspect of teaching and learning. This study focused on the implementation of CA in schools. The study explores how the selected grade 7 Social Studies teachers understand and implement CA. This study was conducted in the Oshana region of Namibia. Four grade 7 Social Studies teachers participated from two different schools. This study was done through a case study to gain insight into the implementation of CA in schools. Semi-structured interviews, observations and document analysis were the research methods used to collect the data. The findings indicate that these teachers have a theoretical understanding of what CA implies and what role it plays and are aware of assessment strategies. However these theoretical perspectives are not translated into practice. This implies a limited understanding of CA and reflects a gap between the teachers’ theoretical understanding of CA and its practical implementation. The study also identified various systemic factors that hamper the implementation of CA, which include overcrowded classrooms, increased teachers’ workload by CA, shortages of resources such as textbooks and lack of professional development. The nature of pre-service teacher education the participants went through, professional development programmes that are given to teachers as in-service training and a lack of guidelines in the syllabus on how to approach continuous assessment are clearly evident in the findings as factors that contribute to the teachers’ gap between theory and practice. The study concludes that even though a number of workshops on continuous assessment were conducted, the teachers still could not implement it as expected. The study findings inform my professional context as an Advisory Teacher and that of my colleagues. Therefore it made me realize what the teachers’ needs are and what kind of support they require.
- Full Text:
- Authors: Matheus, Hilya
- Date: 2007
- Subjects: Educational tests and measurements -- Namibia Social sciences -- Study and teaching (Elementary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1593 , http://hdl.handle.net/10962/d1003475
- Description: Since independence in 1990, Namibia’s Ministry of Education Sport and Culture has focused on curriculum and assessment reforms. The introduction of Continuous Assessment (CA) for appraising learners’ achievement was considered to be a very important aspect of teaching and learning. This study focused on the implementation of CA in schools. The study explores how the selected grade 7 Social Studies teachers understand and implement CA. This study was conducted in the Oshana region of Namibia. Four grade 7 Social Studies teachers participated from two different schools. This study was done through a case study to gain insight into the implementation of CA in schools. Semi-structured interviews, observations and document analysis were the research methods used to collect the data. The findings indicate that these teachers have a theoretical understanding of what CA implies and what role it plays and are aware of assessment strategies. However these theoretical perspectives are not translated into practice. This implies a limited understanding of CA and reflects a gap between the teachers’ theoretical understanding of CA and its practical implementation. The study also identified various systemic factors that hamper the implementation of CA, which include overcrowded classrooms, increased teachers’ workload by CA, shortages of resources such as textbooks and lack of professional development. The nature of pre-service teacher education the participants went through, professional development programmes that are given to teachers as in-service training and a lack of guidelines in the syllabus on how to approach continuous assessment are clearly evident in the findings as factors that contribute to the teachers’ gap between theory and practice. The study concludes that even though a number of workshops on continuous assessment were conducted, the teachers still could not implement it as expected. The study findings inform my professional context as an Advisory Teacher and that of my colleagues. Therefore it made me realize what the teachers’ needs are and what kind of support they require.
- Full Text:
Isolation and characterization of genes encoding heat shock protein 70s (hsp 70s) from two species of the coelacanth, Latimeria chalumnae and Latimeria menadoensis
- Modisakeng, Keoagile William
- Authors: Modisakeng, Keoagile William
- Date: 2007
- Subjects: Coelacanth Coelacanth -- Genetics Heat shock proteins Molecular chaperones Proteins -- Analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3971 , http://hdl.handle.net/10962/d1004030
- Description: The extant coelacanths have a close resemblance to the coelacanth fossil records dating back to 230mya. Like their predecessors, the extant coelacanths inhabit rocky caves at a depth of 100-300m below sea level. In the Comoros, the water temperature at these depths is estimated to fluctuate between 14-20°C. High-level adaptation to these environment and lack of competition are thought to have led to the morphological uniformity and slow change throughout the history of the coelacanths. Under stress conditions, proteins unfold or misfold leading to the formation of aggregates. Molecular chaperones facilitate the correct folding of other proteins so that they can attain a stable tertiary structure. In addition, molecular chaperones aid the refolding of denatured proteins and the degradation of terminally misfolded protein after cellular stress. Heat shock proteins form one of the major classes of molecular chaperones. Here we show that, despite high-level adaptation to a unique habitat and slow change, the genome of the coelacanth encodes the major and highly conserved molecular chaperone, Hsp70. Latimeria menadoensis and Latimeria chalumnae contain intronless hsp70 genes encoding Hsp70 proteins archetypal of known Hsp70s. Based on the coelacanth codon usage, we have shown that bacterial protein expression systems, particularly Escherichia coli, may not be appropriate for the overproduction of coelacanth Hsp70s and coelacanth proteins in general. Also interesting, was the discovery that like the rat Hsc70, the L. menadoensis Hsp70 could not reverse thermal sensitivity in a temperate sensitive E. coli DnaK mutant strain, BB2362. We also report the successful isolation of a 1.2 kb region of L. menadoensis hsp70 upstream regulatory region. This region contain three putative heat shock elements, a TATA- box and two CAAT-boxes. This regulatory region resembled the Xenopus, mouse, and particularly tilapia hsp70 promoters, all of which have been shown to drive the expression of reporter genes in a heat dependent manner. Taken together, this data is the first to strongly suggest an inducible Hsp70-base cytoprotection mechanism in the coelacanth. It further provides basis to formulate testable predictions about the regulation, structure and function of Hsp70s in the living fossil, Latimeria.
- Full Text:
- Authors: Modisakeng, Keoagile William
- Date: 2007
- Subjects: Coelacanth Coelacanth -- Genetics Heat shock proteins Molecular chaperones Proteins -- Analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3971 , http://hdl.handle.net/10962/d1004030
- Description: The extant coelacanths have a close resemblance to the coelacanth fossil records dating back to 230mya. Like their predecessors, the extant coelacanths inhabit rocky caves at a depth of 100-300m below sea level. In the Comoros, the water temperature at these depths is estimated to fluctuate between 14-20°C. High-level adaptation to these environment and lack of competition are thought to have led to the morphological uniformity and slow change throughout the history of the coelacanths. Under stress conditions, proteins unfold or misfold leading to the formation of aggregates. Molecular chaperones facilitate the correct folding of other proteins so that they can attain a stable tertiary structure. In addition, molecular chaperones aid the refolding of denatured proteins and the degradation of terminally misfolded protein after cellular stress. Heat shock proteins form one of the major classes of molecular chaperones. Here we show that, despite high-level adaptation to a unique habitat and slow change, the genome of the coelacanth encodes the major and highly conserved molecular chaperone, Hsp70. Latimeria menadoensis and Latimeria chalumnae contain intronless hsp70 genes encoding Hsp70 proteins archetypal of known Hsp70s. Based on the coelacanth codon usage, we have shown that bacterial protein expression systems, particularly Escherichia coli, may not be appropriate for the overproduction of coelacanth Hsp70s and coelacanth proteins in general. Also interesting, was the discovery that like the rat Hsc70, the L. menadoensis Hsp70 could not reverse thermal sensitivity in a temperate sensitive E. coli DnaK mutant strain, BB2362. We also report the successful isolation of a 1.2 kb region of L. menadoensis hsp70 upstream regulatory region. This region contain three putative heat shock elements, a TATA- box and two CAAT-boxes. This regulatory region resembled the Xenopus, mouse, and particularly tilapia hsp70 promoters, all of which have been shown to drive the expression of reporter genes in a heat dependent manner. Taken together, this data is the first to strongly suggest an inducible Hsp70-base cytoprotection mechanism in the coelacanth. It further provides basis to formulate testable predictions about the regulation, structure and function of Hsp70s in the living fossil, Latimeria.
- Full Text:
Isolation of a Clostridium Beijerinckii sLM01 cellulosome and the effect of sulphide on anaerobic digestion
- Authors: Mayende, Lungisa
- Date: 2007
- Subjects: Cellulose , Clostridium , Cellulase , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3973 , http://hdl.handle.net/10962/d1004032 , Cellulose , Clostridium , Cellulase , Sulfides
- Description: Cellulose is the most abundant and the most resistant and stable natural organic compound on earth. Enzyme hydrolysis is difficult because of its insolubility and heterogeneity. Some (anaerobic) microorganisms have overcome this by having a multienzyme system called the cellulosome. The aims of the study were to isolate a mesophilic Clostridium sp. from a biosulphidogenic bioreactor, to purify the cellulosome from this culture, to determine the cellulase and endoglucanase activities using Avicel and carboxymethylcellulose (CMC) as substrates and the dinitrosalicyclic (DNS) method. The organism was identified using 16S rDNA sequence analysis. The sequence obtained indicated that a strain of Clostridium beijerinckii was isolated. The cellulosome was purified from the putative C. beijerinckii sLM01 host culture using affinity chromatography purification and affinity digestion purification procedures. The cellulosomal and non-cellulosomal fractions of C. beijerinckii sLM01 were separated successfully, but the majority of the endoglucanase activity was lost during the Sepharose 4B chromatography step. These cellulosomal and non-cellulosomal fractions were characterised with regards to their pH and temperature optima and effector sensitivity. Increased additions of sulphide activated the cellulase activity of the cellulosomal and non-cellulosomal fractions up to 700 %, while increased additions of sulphate either increased the activity slightly or inhibited it dramatically, depending on the cellulosomal and non-cellulosomal fractions. Increased additions of cellobiose, glucose and acetate inhibited the cellulase and endoglucanase activities. pH optima of 5.0 and 7.5 were observed for cellulases and 5.0 for endoglucanases of the cellulosomal fraction. The noncellulosomal fraction exhibited a pH optimum of 7.5 for both cellulase and endoglucanase activities. Both fractions and enzymes exhibited a temperature optimum of 30 °C. The fundamental knowledge gained from the characterisation was applied to anaerobic digestion, where the effect of sulphide on the rate-limiting step was determined. Sulphide activated cellulase and endoglucanase activities and increased the % chemical oxygen demand (COD) removal rate. Levels of volatile fatty acids (VFAs) were higher in the bioreactor containing sulphide, substrate and C. beijerinckii. Sulphide therefore accelerated the rate-limiting step of anaerobic digestion.
- Full Text:
- Authors: Mayende, Lungisa
- Date: 2007
- Subjects: Cellulose , Clostridium , Cellulase , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3973 , http://hdl.handle.net/10962/d1004032 , Cellulose , Clostridium , Cellulase , Sulfides
- Description: Cellulose is the most abundant and the most resistant and stable natural organic compound on earth. Enzyme hydrolysis is difficult because of its insolubility and heterogeneity. Some (anaerobic) microorganisms have overcome this by having a multienzyme system called the cellulosome. The aims of the study were to isolate a mesophilic Clostridium sp. from a biosulphidogenic bioreactor, to purify the cellulosome from this culture, to determine the cellulase and endoglucanase activities using Avicel and carboxymethylcellulose (CMC) as substrates and the dinitrosalicyclic (DNS) method. The organism was identified using 16S rDNA sequence analysis. The sequence obtained indicated that a strain of Clostridium beijerinckii was isolated. The cellulosome was purified from the putative C. beijerinckii sLM01 host culture using affinity chromatography purification and affinity digestion purification procedures. The cellulosomal and non-cellulosomal fractions of C. beijerinckii sLM01 were separated successfully, but the majority of the endoglucanase activity was lost during the Sepharose 4B chromatography step. These cellulosomal and non-cellulosomal fractions were characterised with regards to their pH and temperature optima and effector sensitivity. Increased additions of sulphide activated the cellulase activity of the cellulosomal and non-cellulosomal fractions up to 700 %, while increased additions of sulphate either increased the activity slightly or inhibited it dramatically, depending on the cellulosomal and non-cellulosomal fractions. Increased additions of cellobiose, glucose and acetate inhibited the cellulase and endoglucanase activities. pH optima of 5.0 and 7.5 were observed for cellulases and 5.0 for endoglucanases of the cellulosomal fraction. The noncellulosomal fraction exhibited a pH optimum of 7.5 for both cellulase and endoglucanase activities. Both fractions and enzymes exhibited a temperature optimum of 30 °C. The fundamental knowledge gained from the characterisation was applied to anaerobic digestion, where the effect of sulphide on the rate-limiting step was determined. Sulphide activated cellulase and endoglucanase activities and increased the % chemical oxygen demand (COD) removal rate. Levels of volatile fatty acids (VFAs) were higher in the bioreactor containing sulphide, substrate and C. beijerinckii. Sulphide therefore accelerated the rate-limiting step of anaerobic digestion.
- Full Text:
Isolation of microsatellite markers for the endangered Knysna seahorse Hippocampus capensis and their use in the detection of a genetic bottleneck
- Galbusera, Peter H A, Gillemot, Sarah, Jouk, Phillippe, Teske, Peter R, Hellemans, Bart, Volckaert, Filip A M J
- Authors: Galbusera, Peter H A , Gillemot, Sarah , Jouk, Phillippe , Teske, Peter R , Hellemans, Bart , Volckaert, Filip A M J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445678 , vital:74413 , https://doi.org/10.1111/j.1471-8286.2007.01688.x
- Description: We report the isolation and characterization of 15 (12 di‐, 1 tri‐ and 2 tetranucleotide) microsatellite markers from Hippocampus capensis, the Knysna seahorse. This marker set allows the detection of a genetic bottleneck as shown in a captive population. Furthermore, we test their genotyping potential in eight other seahorse taxa.
- Full Text:
- Authors: Galbusera, Peter H A , Gillemot, Sarah , Jouk, Phillippe , Teske, Peter R , Hellemans, Bart , Volckaert, Filip A M J
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445678 , vital:74413 , https://doi.org/10.1111/j.1471-8286.2007.01688.x
- Description: We report the isolation and characterization of 15 (12 di‐, 1 tri‐ and 2 tetranucleotide) microsatellite markers from Hippocampus capensis, the Knysna seahorse. This marker set allows the detection of a genetic bottleneck as shown in a captive population. Furthermore, we test their genotyping potential in eight other seahorse taxa.
- Full Text:
Isolation, propagation and rapid molecular detection of the Kalahari truffle, a mycorrhizal fungus occurring in South Africa
- Authors: Adeleke, Rasheed Adegbola
- Date: 2007 , 2013-04-03
- Subjects: Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3889 , http://hdl.handle.net/10962/d1002951 , Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Description: Terfezia pfeilii is an edible mycorrhizal fungus that thrives in the Kalahari Desert of southern Africa. It is best known by desert dwellers for its flavour and as a source of nutrition. Although the genus Terfezia is generally regarded as being an ectomycorrhizal mycobiont, the exact mycorrhizal type formed by T. pfeilli and its' associated host plants remains uncertain. Discovery of the host plants for T. pfeilii would first be required in order to further investigate the life cycle and cultivation of this truffle. This study focussed on the isolation of mycelia from the ascocarp, optimising the growth conditions of the mycelial cultures, rapid molecular identification of T. pfeilii, investigation of potential helper bacteria and mycorrhizal synthesis experiments. T. pfeilii ascocarps were harvested from the Spitskop Nature Reserve in Upington, South Africa. Ascocarps were successfully identified using both morphological and molecular methods. Despite the delayed growth mostly caused by contaminating microorganisms, the isolation of T. pfeilii mycelia culture was successful. Molecular techniques were used to confirm the identity of the pure culture. Further studies were conducted on ways to improve the growth conditions of the mycelial culture on Fontana medium. An optimum temperature of 32°C, the addition of Bovine Serum Albumin as a nitrogen source and a pH of 7.5 significantly improved the growth of T. pfeilii in vitro. A rapid PeR-based molecular method was developed to speed up the identification of T. pfeilii. Specific primers that can exclusively amplify the ITS region of T. pfeilii were designed and used to identify both the ascocarps and the mycelial culture. The specificity of these primers was confirmed by their inability to amplify DNA from the isolates of contamining fungi obtained during the isolation process. Molecular comparison was made to confirm the reclassification of South African samples of T. pfeilii as Kalaharituber pfeilii as proposed by Ferdman et al.,(2005). However, in this study, the name T. pfeilii has been retained. A total of 17 bacterial isolates were obtained from the fruiting bodies of T. pfeaii and these were tested for stimulation of mycelial growth in vitro, indole production and phosphate solubilising capabilities. Bacterial isolates that showed potential to be Mycorrhization Helper Bacteria (MHB) were identified as Paenibacillus sp., Bacillus sp. and Rhizobium tropici. Selected plant seedlings were inoculated with T. pfeilii cultures or ascocarp slurry in order to re-establish the mycorrhizal association. After 8 months, light microscopy observations revealed an endomycorrhizal type association between Cynodon dactylon and T. pfeilii. This was confirmed with molecular analysis using specific T. pfeilii ITS primers. After 15 months, molecular methods confirmed Acacia erioloba as another host plant. These results have provided essential information paving the way for further investigation into the life cycle and biology of the Kalahari truffle. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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- Authors: Adeleke, Rasheed Adegbola
- Date: 2007 , 2013-04-03
- Subjects: Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3889 , http://hdl.handle.net/10962/d1002951 , Truffles -- Kalahari Desert , Fungi -- Identification , Mycorrhizal fungi -- South Africa , Edible fungi -- South Africa , Mushroom culture -- South Africa , Fungi -- Cultures and culture media -- South Africa , Truffles -- South Africa , Truffles -- Lifecycles , Mycorrhizal fungi -- Lifecycles
- Description: Terfezia pfeilii is an edible mycorrhizal fungus that thrives in the Kalahari Desert of southern Africa. It is best known by desert dwellers for its flavour and as a source of nutrition. Although the genus Terfezia is generally regarded as being an ectomycorrhizal mycobiont, the exact mycorrhizal type formed by T. pfeilli and its' associated host plants remains uncertain. Discovery of the host plants for T. pfeilii would first be required in order to further investigate the life cycle and cultivation of this truffle. This study focussed on the isolation of mycelia from the ascocarp, optimising the growth conditions of the mycelial cultures, rapid molecular identification of T. pfeilii, investigation of potential helper bacteria and mycorrhizal synthesis experiments. T. pfeilii ascocarps were harvested from the Spitskop Nature Reserve in Upington, South Africa. Ascocarps were successfully identified using both morphological and molecular methods. Despite the delayed growth mostly caused by contaminating microorganisms, the isolation of T. pfeilii mycelia culture was successful. Molecular techniques were used to confirm the identity of the pure culture. Further studies were conducted on ways to improve the growth conditions of the mycelial culture on Fontana medium. An optimum temperature of 32°C, the addition of Bovine Serum Albumin as a nitrogen source and a pH of 7.5 significantly improved the growth of T. pfeilii in vitro. A rapid PeR-based molecular method was developed to speed up the identification of T. pfeilii. Specific primers that can exclusively amplify the ITS region of T. pfeilii were designed and used to identify both the ascocarps and the mycelial culture. The specificity of these primers was confirmed by their inability to amplify DNA from the isolates of contamining fungi obtained during the isolation process. Molecular comparison was made to confirm the reclassification of South African samples of T. pfeilii as Kalaharituber pfeilii as proposed by Ferdman et al.,(2005). However, in this study, the name T. pfeilii has been retained. A total of 17 bacterial isolates were obtained from the fruiting bodies of T. pfeaii and these were tested for stimulation of mycelial growth in vitro, indole production and phosphate solubilising capabilities. Bacterial isolates that showed potential to be Mycorrhization Helper Bacteria (MHB) were identified as Paenibacillus sp., Bacillus sp. and Rhizobium tropici. Selected plant seedlings were inoculated with T. pfeilii cultures or ascocarp slurry in order to re-establish the mycorrhizal association. After 8 months, light microscopy observations revealed an endomycorrhizal type association between Cynodon dactylon and T. pfeilii. This was confirmed with molecular analysis using specific T. pfeilii ITS primers. After 15 months, molecular methods confirmed Acacia erioloba as another host plant. These results have provided essential information paving the way for further investigation into the life cycle and biology of the Kalahari truffle. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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JM Coetzee and the ethics of reading:
- Authors: Marais, Mike
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144253 , vital:38325 , https://www.jstor.org/stable/pdf/26286886.pdf
- Description: One of Derek Attridge's principal concerns in J. M. Coetzee and the Ethics of Reading is the relationship that is established with alterity in the writing and reading of literary works. As is evident from the fact that some of the chapters in the book date back more than a decade, this is an abiding concern. Indeed, The Singularity of Literature, which also appeared in 2004, theorizes this relationship at great length. In it, Attridge describes the literary text as the emanation of an act of creation, that is, that mysterious experience in which the writer, who is located in culture's familiar modes of understanding, encounters something strange (in that it does not yet exist within the horizon that culture provides for thinking and feeling) and is required to resist the mind's tendency to reduce novelty by understanding it in terms of the familiar.
- Full Text:
- Authors: Marais, Mike
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144253 , vital:38325 , https://www.jstor.org/stable/pdf/26286886.pdf
- Description: One of Derek Attridge's principal concerns in J. M. Coetzee and the Ethics of Reading is the relationship that is established with alterity in the writing and reading of literary works. As is evident from the fact that some of the chapters in the book date back more than a decade, this is an abiding concern. Indeed, The Singularity of Literature, which also appeared in 2004, theorizes this relationship at great length. In it, Attridge describes the literary text as the emanation of an act of creation, that is, that mysterious experience in which the writer, who is located in culture's familiar modes of understanding, encounters something strange (in that it does not yet exist within the horizon that culture provides for thinking and feeling) and is required to resist the mind's tendency to reduce novelty by understanding it in terms of the familiar.
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John Michael Berning (14.12.1941- 17.12.2006) : obituary
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
- Full Text:
- Authors: Lewis, Colin A
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6184 , http://hdl.handle.net/10962/d1012381
- Description: [From Introduction] Mike Berning was born in 1941. He attended the King Edward VII School in Johannesburg before going up to Rhodes University in 1960, where he read Honours in History, graduating in 1963. Having decided on a career in librarianship, Mike proceeded from Rhodes to the University of Cape Town in 1964, initially to read for a Certificate in that subject. In 1968 he was awarded his Diploma in Librarianship from UCT. In the first part of 1965 Mike was employed in the South African Library in Cape Town, but in September of that year he was appointed Librarian of the Cory Library at Rhodes University. From 1978 until 1986 he acted as Deputy to the University Librarian until, in 1988, the post of Deputy University Librarian was created, to which he was appointed. Mike retired in 1999. , Colin Lewis was Professor of Geography at Rhodes University, Grahamstown, South Africa from 1989 until his retirement at the end of 2007. In 1990, with the strong support of the incumbent Vice-Chancellor, Dr Derek Henderson, he instigated the Certificate in Change Ringing (Church Bell Ringing) in the Rhodes University Department of Music and Musicology - the first such course to be offered in Africa. Since that date he has lectured in the basic theory, and taught the practice of change ringing. He is the Ringing Master of the Cathedral of St Michael and St George, Grahamstown, South Africa.
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