Environmental education in primary schools in Bophuthatswana : a case study in curriculum implementation
- Authors: Shongwe, Doctor Petrus
- Date: 1992
- Subjects: Environmental education -- South Africa -- Bophuthatswana , Primary school teaching -- Research -- South Africa -- Bophuthatswana
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1514 , http://hdl.handle.net/10962/d1003396
- Description: This study examines the extent to which teachers in Senior Primary Schools who have obtained a professional qualification in Environmental Education, implement Environmental Education in their schools. It also explores factors which influence the implementation of Environmental Education at the Senior Primary School. Teachers who had qualified from Tlhabane and Hebron Colleges of Education were interviewed as were the principals of their schools and some of the lecturers who had taught them Environmental Education. The implementation of Environmental Education was addressed by means of comparing the teacher's responses with Primary Environmental Education Teacher Competencies as suggested by Glasgow and Robinson (1986) and Lahiry et al (1988). The information was deduced from the teachers responses from semi-structured interviews and were qualitatively analysed.
- Full Text:
- Date Issued: 1992
- Authors: Shongwe, Doctor Petrus
- Date: 1992
- Subjects: Environmental education -- South Africa -- Bophuthatswana , Primary school teaching -- Research -- South Africa -- Bophuthatswana
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1514 , http://hdl.handle.net/10962/d1003396
- Description: This study examines the extent to which teachers in Senior Primary Schools who have obtained a professional qualification in Environmental Education, implement Environmental Education in their schools. It also explores factors which influence the implementation of Environmental Education at the Senior Primary School. Teachers who had qualified from Tlhabane and Hebron Colleges of Education were interviewed as were the principals of their schools and some of the lecturers who had taught them Environmental Education. The implementation of Environmental Education was addressed by means of comparing the teacher's responses with Primary Environmental Education Teacher Competencies as suggested by Glasgow and Robinson (1986) and Lahiry et al (1988). The information was deduced from the teachers responses from semi-structured interviews and were qualitatively analysed.
- Full Text:
- Date Issued: 1992
The feeding ecology, habitat selection and hunting behaviour of re-introduced cheetah on Kwandwe Private Game Reserve, Eastern Cape Province
- Authors: Bissett, Charlene
- Date: 2005
- Subjects: Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5698 , http://hdl.handle.net/10962/d1005384 , Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Description: The re-introduction of cheetah onto small reserves in the Eastern Cape Province has created the opportunity to study this species in an environment (Valley Bushveld) in which it has not previously been studied and which is quite different from the less wooded habitats in which previous studies have occurred. Thus the aim of this study is to add to the growing number of studies of cheetah in more wooded habitats and to contribute a better understanding of the level of specialization or adaptability in space use, habitat selection, diet and hunting behaviour that the cheetah possesses. The research was conducted on Kwandwe Private Game Reserve from February 2003 to August 2004. Direct observations, scat analysis and continuous observations were used to avoid bias towards large sized prey found when only using direct observations to study diet. The cheetah killed 15 species and four of the five most important prey species (kudu, springbok, grey duiker and bushbuck) were hunted according to their abundance on the reserve, while impala, the fifth most important prey species, was avoided (i.e. preference index less than one) by the cheetah. The cheetah’s main prey was medium sized ungulates, although the three male coalition killed larger prey than females and females with cubs. The daily food intake per cheetah per day was calculated to range from 5.3kg/cheetah/day for the coalition to 8kg/cheetah/day for a solitary female. Home range areas ranged from 11.1 km² for female cheetah with cubs in a den to 65.6 km² for single female cheetah and core areas ranged from 6 km² for the three male coalition to 26.5 km² for independent cubs. Habitat selection by cheetah on Kwandwe varied between the social groups depending on their susceptibility to predation by lions, their need for cover and need for water, and was similar to what has been previously reported. The home range of the coalition incorporated the most open vegetation type (karroid shrubland) with surrounding denser vegetation, while females occupied areas of denser vegetation. Activity patterns and hunting behaviour varied between different cheetah social groups with female cheetah being more active during day light hours compared to males which made 38% of their kills after dark. The average chase distances for the various cheetah groups varied considerably, and the chase distance for successful hunts was longer than for unsuccessful for all groups except single female cheetah. The percentage of kills’ kleptoparasitised on Kwandwe was very low compared to other studies possibly due to the low density of direct competitors, which in turn lead to longer mean kill retention times. These results suggest that cheetah are more adaptable than previously thought and this adaptability may have important implications for their conservation.
- Full Text:
- Date Issued: 2005
- Authors: Bissett, Charlene
- Date: 2005
- Subjects: Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5698 , http://hdl.handle.net/10962/d1005384 , Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Description: The re-introduction of cheetah onto small reserves in the Eastern Cape Province has created the opportunity to study this species in an environment (Valley Bushveld) in which it has not previously been studied and which is quite different from the less wooded habitats in which previous studies have occurred. Thus the aim of this study is to add to the growing number of studies of cheetah in more wooded habitats and to contribute a better understanding of the level of specialization or adaptability in space use, habitat selection, diet and hunting behaviour that the cheetah possesses. The research was conducted on Kwandwe Private Game Reserve from February 2003 to August 2004. Direct observations, scat analysis and continuous observations were used to avoid bias towards large sized prey found when only using direct observations to study diet. The cheetah killed 15 species and four of the five most important prey species (kudu, springbok, grey duiker and bushbuck) were hunted according to their abundance on the reserve, while impala, the fifth most important prey species, was avoided (i.e. preference index less than one) by the cheetah. The cheetah’s main prey was medium sized ungulates, although the three male coalition killed larger prey than females and females with cubs. The daily food intake per cheetah per day was calculated to range from 5.3kg/cheetah/day for the coalition to 8kg/cheetah/day for a solitary female. Home range areas ranged from 11.1 km² for female cheetah with cubs in a den to 65.6 km² for single female cheetah and core areas ranged from 6 km² for the three male coalition to 26.5 km² for independent cubs. Habitat selection by cheetah on Kwandwe varied between the social groups depending on their susceptibility to predation by lions, their need for cover and need for water, and was similar to what has been previously reported. The home range of the coalition incorporated the most open vegetation type (karroid shrubland) with surrounding denser vegetation, while females occupied areas of denser vegetation. Activity patterns and hunting behaviour varied between different cheetah social groups with female cheetah being more active during day light hours compared to males which made 38% of their kills after dark. The average chase distances for the various cheetah groups varied considerably, and the chase distance for successful hunts was longer than for unsuccessful for all groups except single female cheetah. The percentage of kills’ kleptoparasitised on Kwandwe was very low compared to other studies possibly due to the low density of direct competitors, which in turn lead to longer mean kill retention times. These results suggest that cheetah are more adaptable than previously thought and this adaptability may have important implications for their conservation.
- Full Text:
- Date Issued: 2005
Towards a collection of cost-effective technologies in support of the NIST cybersecurity framework
- Shackleton, Bruce Michael Stuart
- Authors: Shackleton, Bruce Michael Stuart
- Date: 2018
- Subjects: National Institute of Standards and Technology (U.S.) , Computer security , Computer networks Security measures , Small business Information technology Cost effectiveness , Open source software
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62494 , vital:28199
- Description: The NIST Cybersecurity Framework (CSF) is a specific risk and cybersecurity framework. It provides guidance on controls that can be implemented to help improve an organisation’s cybersecurity risk posture. The CSF Functions consist of Identify, Protect, Detect, Respond, and Recover. Like most Information Technology (IT) frameworks, there are elements of people, processes, and technology. The same elements are required to successfully implement the NIST CSF. This research specifically focuses on the technology element. While there are many commercial technologies available for a small to medium sized business, the costs can be prohibitively expensive. Therefore, this research investigates cost-effective technologies and assesses their alignment to the NIST CSF. The assessment was made against the NIST CSF subcategories. Each subcategory was analysed to identify where a technology would likely be required. The framework provides a list of Informative References. These Informative References were used to create high- level technology categories, as well as identify the technical controls against which the technologies were measured. The technologies tested were either open source or proprietary. All open source technologies tested were free to use, or have a free community edition. Proprietary technologies would be free to use, or considered generally available to most organisations, such as components contained within Microsoft platforms. The results from the experimentation demonstrated that there are multiple cost-effective technologies that can support the NIST CSF. Once all technologies were tested, the NIST CSF was extended. Two new columns were added, namely high-level technology category, and tested technology. The columns were populated with output from the research. This extended framework begins an initial collection of cost-effective technologies in support of the NIST CSF.
- Full Text:
- Date Issued: 2018
- Authors: Shackleton, Bruce Michael Stuart
- Date: 2018
- Subjects: National Institute of Standards and Technology (U.S.) , Computer security , Computer networks Security measures , Small business Information technology Cost effectiveness , Open source software
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62494 , vital:28199
- Description: The NIST Cybersecurity Framework (CSF) is a specific risk and cybersecurity framework. It provides guidance on controls that can be implemented to help improve an organisation’s cybersecurity risk posture. The CSF Functions consist of Identify, Protect, Detect, Respond, and Recover. Like most Information Technology (IT) frameworks, there are elements of people, processes, and technology. The same elements are required to successfully implement the NIST CSF. This research specifically focuses on the technology element. While there are many commercial technologies available for a small to medium sized business, the costs can be prohibitively expensive. Therefore, this research investigates cost-effective technologies and assesses their alignment to the NIST CSF. The assessment was made against the NIST CSF subcategories. Each subcategory was analysed to identify where a technology would likely be required. The framework provides a list of Informative References. These Informative References were used to create high- level technology categories, as well as identify the technical controls against which the technologies were measured. The technologies tested were either open source or proprietary. All open source technologies tested were free to use, or have a free community edition. Proprietary technologies would be free to use, or considered generally available to most organisations, such as components contained within Microsoft platforms. The results from the experimentation demonstrated that there are multiple cost-effective technologies that can support the NIST CSF. Once all technologies were tested, the NIST CSF was extended. Two new columns were added, namely high-level technology category, and tested technology. The columns were populated with output from the research. This extended framework begins an initial collection of cost-effective technologies in support of the NIST CSF.
- Full Text:
- Date Issued: 2018
Buffering strategies and bandwidth renegotiation for MPEG video streams
- Authors: Schonken, Nico
- Date: 1999
- Subjects: Video compression , Computer algorithms , Digital video
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4651 , http://hdl.handle.net/10962/d1006620 , Video compression , Computer algorithms , Digital video
- Description: This paper confirms the existence of short-term and long-term variation of the required bandwidth for MPEG videostreams. We show how the use of a small amount of buffering and GOP grouping can significantly reduce the effect of the short-term variation. By introducing a number of bandwidth renegotiation techniques, which can be applied to MPEG video streams in general, we are able to reduce the effect of long-term variation. These techniques include those that need the a priori knowledge of frame sizes as well as one that can renegotiate dynamically. A costing algorithm has also been introduced in order to compare various proposals against each other.
- Full Text:
- Date Issued: 1999
- Authors: Schonken, Nico
- Date: 1999
- Subjects: Video compression , Computer algorithms , Digital video
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4651 , http://hdl.handle.net/10962/d1006620 , Video compression , Computer algorithms , Digital video
- Description: This paper confirms the existence of short-term and long-term variation of the required bandwidth for MPEG videostreams. We show how the use of a small amount of buffering and GOP grouping can significantly reduce the effect of the short-term variation. By introducing a number of bandwidth renegotiation techniques, which can be applied to MPEG video streams in general, we are able to reduce the effect of long-term variation. These techniques include those that need the a priori knowledge of frame sizes as well as one that can renegotiate dynamically. A costing algorithm has also been introduced in order to compare various proposals against each other.
- Full Text:
- Date Issued: 1999
Interrogating the specific challenges of teaching play texts in heterogeneous classrooms in the Eastern Cape
- Authors: Hayes, Nicola
- Date: 2016
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:6022 , http://hdl.handle.net/10962/d1021251
- Description: This study is an autoethnographic reflection, rooted in Action Research based on my teaching experience in a multicultural high school environment in the Eastern Cape, South Africa. It is an analysis, in particular, of teaching play texts in two classes, Dramatic Arts and English Home Language, at matric level. A combination of discourse analysis and autoethnography formed the theoretical basis for the interpretation of data drawn from lesson transcripts, group interviews, learners’ reflections and my own journalled reflections. This analysis has formed the foundation for a deeper reflection on culture, the colonist within, and the colonialism embedded with in my teaching, and in the education system more broadly. At a practical level, I suggest embracing student-led and co-led discussions of literature, as advocated by Mayer (2012), as well as transcultural readings (Keating, 2007), and Drama activities, as ideals in the teaching of play texts. These techniques are designed to encourage learners to develop intellectual authority as well as allowing them the space to enter discussions around culturally sensitive topics, while minimising the teacher’s hierarchical, dominant position. I also argue for the importance of making culture an overt topic of conversation. White English-speaking South African culture, in particular has been prone to “invisibility” and, through this, an unspoken normative position, particularly in multicultural school environments. I challenge myself and others to engage in ongoing efforts to articulate our particular perception of our cultures, dynamic and diverse though they may be.
- Full Text:
- Date Issued: 2016
- Authors: Hayes, Nicola
- Date: 2016
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:6022 , http://hdl.handle.net/10962/d1021251
- Description: This study is an autoethnographic reflection, rooted in Action Research based on my teaching experience in a multicultural high school environment in the Eastern Cape, South Africa. It is an analysis, in particular, of teaching play texts in two classes, Dramatic Arts and English Home Language, at matric level. A combination of discourse analysis and autoethnography formed the theoretical basis for the interpretation of data drawn from lesson transcripts, group interviews, learners’ reflections and my own journalled reflections. This analysis has formed the foundation for a deeper reflection on culture, the colonist within, and the colonialism embedded with in my teaching, and in the education system more broadly. At a practical level, I suggest embracing student-led and co-led discussions of literature, as advocated by Mayer (2012), as well as transcultural readings (Keating, 2007), and Drama activities, as ideals in the teaching of play texts. These techniques are designed to encourage learners to develop intellectual authority as well as allowing them the space to enter discussions around culturally sensitive topics, while minimising the teacher’s hierarchical, dominant position. I also argue for the importance of making culture an overt topic of conversation. White English-speaking South African culture, in particular has been prone to “invisibility” and, through this, an unspoken normative position, particularly in multicultural school environments. I challenge myself and others to engage in ongoing efforts to articulate our particular perception of our cultures, dynamic and diverse though they may be.
- Full Text:
- Date Issued: 2016
Towards large scale software based network routing simulation
- Authors: Herbert, Alan
- Date: 2015
- Subjects: Routers (Computer networks) , Computer software , Linux
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4709 , http://hdl.handle.net/10962/d1017931
- Description: Software based routing simulators suffer from large simulation host requirements and are prone to slow downs because of resource limitations, as well as context switching due to user space to kernel space requests. Furthermore, hardware based simulations do not scale with the passing of time as their available resources are set at the time of manufacture. This research aims to provide a software based, scalable solution to network simulation. It aims to achieve this by a Linux kernel-based solution, through insertion of a custom kernel module. This will reduce the number of context switches by eliminating the user space context requirement, and serve to be highly compatible with any host that can run the Linux kernel. Through careful consideration in data structure choice and software component design, this routing simulator achieved results of over 7 Gbps of throughput over multiple simulated node hops on consumer hardware. Alongside this throughput, this routing simulator also brings to light scalability and the ability to instantiate and simulate networks in excess of 1 million routing nodes within 1 GB of system memory
- Full Text:
- Date Issued: 2015
- Authors: Herbert, Alan
- Date: 2015
- Subjects: Routers (Computer networks) , Computer software , Linux
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4709 , http://hdl.handle.net/10962/d1017931
- Description: Software based routing simulators suffer from large simulation host requirements and are prone to slow downs because of resource limitations, as well as context switching due to user space to kernel space requests. Furthermore, hardware based simulations do not scale with the passing of time as their available resources are set at the time of manufacture. This research aims to provide a software based, scalable solution to network simulation. It aims to achieve this by a Linux kernel-based solution, through insertion of a custom kernel module. This will reduce the number of context switches by eliminating the user space context requirement, and serve to be highly compatible with any host that can run the Linux kernel. Through careful consideration in data structure choice and software component design, this routing simulator achieved results of over 7 Gbps of throughput over multiple simulated node hops on consumer hardware. Alongside this throughput, this routing simulator also brings to light scalability and the ability to instantiate and simulate networks in excess of 1 million routing nodes within 1 GB of system memory
- Full Text:
- Date Issued: 2015
The attitudes and perceptions of secondary school pupils in Transkei towards geography: a case study of the Butterworth district
- Authors: Sarpong, Emmanuel
- Date: 1992
- Subjects: Students, Black -- South Africa -- Attitudes Geography -- South Africa -- Transkei -- Study and teaching (Secondary)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1425 , http://hdl.handle.net/10962/d1003306
- Description: Considerable attention has in recent times been given to the attitudes of secondary school pupils towards Geography among black schools in South Africa. Many reasons account for this. It is partly because of the poor results and falling numbers of pupils in the discipline. Concern has also been expressed on the relevance of the Geography syllabus to the black pupils. Evidence suggests that these problems are evident in Transkei. The need therefore exists to assess pupils' attitudes towards Geography in Transkei. Arising from this background, this study sets out to assess the attitudes of secondary school pupils in Transkei towards Geography. Two hundred and thirty four pupils from eight urban and rural secondary schools in the Butterworth District of the Republic of Transkei were used in the study. Attitudes were measured in terms of "interest in Geography", "desire to study the discipline", "commitment to Geography" and the perceived relevance of the discipline. Through the use of techniques such as percentages, chi-square and principal component analysis - among others - for the analysis of the data, the following information emerged from the study: (1) Geography is generally perceived as being worthy of study; (2) Differences in responses were noted to result from a complex of factors which were grouped into home environmental factors and school environmental ones. (3) The major factor influencing attitudes towards Geography was noted to be home environmental conditions.In general pupils from lower income families expressed more positive views about the worth of Geography than those from the upper income families. From the above findings, it has been proposed that teachers and educational planners need to be made aware of these findings as they are important for classroom practice. It has also been recommended that there is a need to improve certain school practices such as taking pupils on Geography excursions more often as factors such as this were shown to improve pupils' attitudes towards the discipline.
- Full Text:
- Date Issued: 1992
- Authors: Sarpong, Emmanuel
- Date: 1992
- Subjects: Students, Black -- South Africa -- Attitudes Geography -- South Africa -- Transkei -- Study and teaching (Secondary)
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1425 , http://hdl.handle.net/10962/d1003306
- Description: Considerable attention has in recent times been given to the attitudes of secondary school pupils towards Geography among black schools in South Africa. Many reasons account for this. It is partly because of the poor results and falling numbers of pupils in the discipline. Concern has also been expressed on the relevance of the Geography syllabus to the black pupils. Evidence suggests that these problems are evident in Transkei. The need therefore exists to assess pupils' attitudes towards Geography in Transkei. Arising from this background, this study sets out to assess the attitudes of secondary school pupils in Transkei towards Geography. Two hundred and thirty four pupils from eight urban and rural secondary schools in the Butterworth District of the Republic of Transkei were used in the study. Attitudes were measured in terms of "interest in Geography", "desire to study the discipline", "commitment to Geography" and the perceived relevance of the discipline. Through the use of techniques such as percentages, chi-square and principal component analysis - among others - for the analysis of the data, the following information emerged from the study: (1) Geography is generally perceived as being worthy of study; (2) Differences in responses were noted to result from a complex of factors which were grouped into home environmental factors and school environmental ones. (3) The major factor influencing attitudes towards Geography was noted to be home environmental conditions.In general pupils from lower income families expressed more positive views about the worth of Geography than those from the upper income families. From the above findings, it has been proposed that teachers and educational planners need to be made aware of these findings as they are important for classroom practice. It has also been recommended that there is a need to improve certain school practices such as taking pupils on Geography excursions more often as factors such as this were shown to improve pupils' attitudes towards the discipline.
- Full Text:
- Date Issued: 1992
Exploring the correlation between language medium and academic achievement: a comparative study of the language of learning and teaching (LoLT) and mathematics results in the 2010 Grade 12 National Senior Certificate examinations in the Eastern Cape
- Mbude-Shale, Beryl Ntombizanele
- Authors: Mbude-Shale, Beryl Ntombizanele
- Date: 2013
- Subjects: Academic achievement -- Research -- South Africa -- Eastern Cape Language and education -- Research -- South Africa -- Eastern Cape Language policy -- South Africa -- Eastern Cape Mathematics -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Education, Secondary -- South Africa -- Eastern Cape Matric Learners Language planning Mathematics Policies Academic performance Mother-tongue
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3559 , http://hdl.handle.net/10962/d1001863
- Description: In 2009, of the 68,129 learners who wrote Matric, only 34,731 learners passed. In 2010, there was an increase in the provincial pass rate causing much excitement across the board. The reality was that of the 64,090 learners who wrote, only 37,345 learners passed. In 2010, a result below 50% was recorded for Mathematics and Physical Science nationally (DBE; 2011). Despite efforts by the Education Department to support MSTE; establishing Mathematics and Science schools, NGOs and HEIs giving extra Mathematics and Science support to students and teachers, the offering of Saturday classes and incubation camps, we still get minimal return on investment. This thesis analyses these results against the backdrop of language planning theory, particularly language-in-education policies, pre and post-apartheid. The correlation between language medium and academic performance in language (LoLT) and Mathematics of Grade 12 learners is explored. Worldwide the issue of low achievement in Mathematics by ESL students is of great concern (Cuevas, 1984). The 2004 Systemic Evaluation sample of learners was in Grade 6 then; in 2010 they wrote Grade 12. The purpose of the systemic evaluation was to provide an insight into the levels of learner performance in Maths, Natural Science and LoLT in Grade 6 (IPSER, 2006). A major finding of the IPSER was that language was an important factor related to learner achievement. A major disparity was observed in this research, that although the Eastern Cape performed below the national average in the three subjects evaluated, the learners for whom LoLT was the same as their home language obtained scores that were significantly higher than those whose home language was different from the LoLT. The provincial average for Mathematics was 23.40% compared to the national average of 27.80%. For LoLT the province scored 30.16 against the national score of 38.03%. Of interest in this study is a juxtaposition of the Matric results of this same group of learners in 2010 and see whether issues that came up then are still significant in mitigating achievement in Mathematics and Language (LoLT). Some research studies have been conducted in South Africa (Adler, 1998; Setati, 1996-2002; Moloi, 2006) identifying the vital role language plays in learning Mathematics, especially for English L2 learners. Building on research and findings of academics such as the late Alexander, Ramani, Joseph, Hendricks, Heugh, Dalvit, Webb and Murray, this thesis suggests that a mother-tongue-based-bilingual approach to education should be adopted as a matter of urgency
- Full Text:
- Date Issued: 2013
- Authors: Mbude-Shale, Beryl Ntombizanele
- Date: 2013
- Subjects: Academic achievement -- Research -- South Africa -- Eastern Cape Language and education -- Research -- South Africa -- Eastern Cape Language policy -- South Africa -- Eastern Cape Mathematics -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Education, Secondary -- South Africa -- Eastern Cape Matric Learners Language planning Mathematics Policies Academic performance Mother-tongue
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3559 , http://hdl.handle.net/10962/d1001863
- Description: In 2009, of the 68,129 learners who wrote Matric, only 34,731 learners passed. In 2010, there was an increase in the provincial pass rate causing much excitement across the board. The reality was that of the 64,090 learners who wrote, only 37,345 learners passed. In 2010, a result below 50% was recorded for Mathematics and Physical Science nationally (DBE; 2011). Despite efforts by the Education Department to support MSTE; establishing Mathematics and Science schools, NGOs and HEIs giving extra Mathematics and Science support to students and teachers, the offering of Saturday classes and incubation camps, we still get minimal return on investment. This thesis analyses these results against the backdrop of language planning theory, particularly language-in-education policies, pre and post-apartheid. The correlation between language medium and academic performance in language (LoLT) and Mathematics of Grade 12 learners is explored. Worldwide the issue of low achievement in Mathematics by ESL students is of great concern (Cuevas, 1984). The 2004 Systemic Evaluation sample of learners was in Grade 6 then; in 2010 they wrote Grade 12. The purpose of the systemic evaluation was to provide an insight into the levels of learner performance in Maths, Natural Science and LoLT in Grade 6 (IPSER, 2006). A major finding of the IPSER was that language was an important factor related to learner achievement. A major disparity was observed in this research, that although the Eastern Cape performed below the national average in the three subjects evaluated, the learners for whom LoLT was the same as their home language obtained scores that were significantly higher than those whose home language was different from the LoLT. The provincial average for Mathematics was 23.40% compared to the national average of 27.80%. For LoLT the province scored 30.16 against the national score of 38.03%. Of interest in this study is a juxtaposition of the Matric results of this same group of learners in 2010 and see whether issues that came up then are still significant in mitigating achievement in Mathematics and Language (LoLT). Some research studies have been conducted in South Africa (Adler, 1998; Setati, 1996-2002; Moloi, 2006) identifying the vital role language plays in learning Mathematics, especially for English L2 learners. Building on research and findings of academics such as the late Alexander, Ramani, Joseph, Hendricks, Heugh, Dalvit, Webb and Murray, this thesis suggests that a mother-tongue-based-bilingual approach to education should be adopted as a matter of urgency
- Full Text:
- Date Issued: 2013
A study of petrol and diesel fuel blends with special reference to their thermodynamic properties and phase equilibria
- Authors: Heyward, Caroline
- Date: 1986
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:21167 , http://hdl.handle.net/10962/6695
- Description: The ternary phase behaviour of the n-heptane-l-propanol-water system was studied and compared with the theoretical prediction based on the UNIQUAC model for non-electrolyte solutions. The results showed that this model adequately approximated experimental studies. The excess enthalpies and excess volumes for several binary mixtures were determined. The excess enthalpies were measured using a LKB flow microcalorimeter and the excess -volumes determined using a PAAR densitometer. The study showed that no significant enthalpy or volume changes occurred when petrol/n-heptane were mixed with alcohols. Ternary phase diagrams, including tie lines have been determined for a number of petrol-alcohol-water systems (including the Sasol blend of alcohols). The tie line results show that the concentration of water in the water-rich layer is strongly dependent on the type of alcohol used. The Sasol alcohol blended with petrol resulted in a high water concentration in the water-rich layer which forms on phase separation. This is believed to contribute significantly to the corrosion problems experienced by motorists using the Sasol blended fuel on the Witwatersrand. The effect of temperature on several of these blends was included in the study. Diesel-alcohol blends and the co-solvent properties of ethyl acetate investigated. Ethyl acetate ensures miscibility at low concentrations for diesel-ethanol blends. Octyl nitrate and two cetane improvers from AECI were assessed in terms of their ability to restore cetane rating of blended diesel fuel to that of pure diesel fuel. The results indicated that all three samples were successful in this application.
- Full Text:
- Date Issued: 1986
- Authors: Heyward, Caroline
- Date: 1986
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:21167 , http://hdl.handle.net/10962/6695
- Description: The ternary phase behaviour of the n-heptane-l-propanol-water system was studied and compared with the theoretical prediction based on the UNIQUAC model for non-electrolyte solutions. The results showed that this model adequately approximated experimental studies. The excess enthalpies and excess volumes for several binary mixtures were determined. The excess enthalpies were measured using a LKB flow microcalorimeter and the excess -volumes determined using a PAAR densitometer. The study showed that no significant enthalpy or volume changes occurred when petrol/n-heptane were mixed with alcohols. Ternary phase diagrams, including tie lines have been determined for a number of petrol-alcohol-water systems (including the Sasol blend of alcohols). The tie line results show that the concentration of water in the water-rich layer is strongly dependent on the type of alcohol used. The Sasol alcohol blended with petrol resulted in a high water concentration in the water-rich layer which forms on phase separation. This is believed to contribute significantly to the corrosion problems experienced by motorists using the Sasol blended fuel on the Witwatersrand. The effect of temperature on several of these blends was included in the study. Diesel-alcohol blends and the co-solvent properties of ethyl acetate investigated. Ethyl acetate ensures miscibility at low concentrations for diesel-ethanol blends. Octyl nitrate and two cetane improvers from AECI were assessed in terms of their ability to restore cetane rating of blended diesel fuel to that of pure diesel fuel. The results indicated that all three samples were successful in this application.
- Full Text:
- Date Issued: 1986
Enactment of hands-on practical activities through using easily accessible resources in a Grade 10 Physical Science classroom
- Authors: Ndevahoma, Martha Kashike
- Date: 2020
- Subjects: Physical science -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/110229 , vital:33251
- Description: The Namibian National Subject Policy Guide for Physical Science Grade 8-12 (MoE, 2010) indicates that science teachers should be creative and innovative in producing their own teaching and learning support materials that are linked to practice. Practical activities play a major role in the learning of science. Due to the lack of science laboratory equipment, however, minimal practical activities are done in some schools especially under-resourced disadvantaged schools. It is against this background that this case study investigated the possibilities and challenges associated with the use of easily accessible resources to carry out hands-on practical activities. Underpinned by an interpretive paradigm, this study used a mixed-method approach by generating both quantitative and qualitative data. It was carried out in the Otjozondjupa region in Namibia at Wato Secondary School (pseudonym). It was conducted with a Grade 10 Physical Science class consisting of 30 learners. To generate data, questionnaires, focus group interviews, lesson observations, stimulated recall interviews, as well as learners’ journal reflections were used. Conceptions, dispositions, interest and sense-making were used as conceptual lenses while Vygotsky’s social constructivism was the theoretical framework that informed this study. Quantitative data were analysed using the conceptual lenses and were subsequently presented in tables and graphs. That is, a deductive approach to analysis was used. On the other hand, a thematic approach was used to analyse the qualitative data. That is, qualitative data were inductively analysed to come up with sub-themes and themes. The findings from this study revealed significant shifts in learners’ conceptions, dispositions and interest towards science after the use of easily accessible resources to do hands-on practical activities. Similarly, learners’ sense-making of science concepts improved. This study thus recommends that science teachers should, where possible, make use of easily accessible resources to carry out hands-on practical activities during their science lessons. During such hands-on practicals, however, emphasis should be on the development of scientific concepts.
- Full Text:
- Date Issued: 2020
- Authors: Ndevahoma, Martha Kashike
- Date: 2020
- Subjects: Physical science -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/110229 , vital:33251
- Description: The Namibian National Subject Policy Guide for Physical Science Grade 8-12 (MoE, 2010) indicates that science teachers should be creative and innovative in producing their own teaching and learning support materials that are linked to practice. Practical activities play a major role in the learning of science. Due to the lack of science laboratory equipment, however, minimal practical activities are done in some schools especially under-resourced disadvantaged schools. It is against this background that this case study investigated the possibilities and challenges associated with the use of easily accessible resources to carry out hands-on practical activities. Underpinned by an interpretive paradigm, this study used a mixed-method approach by generating both quantitative and qualitative data. It was carried out in the Otjozondjupa region in Namibia at Wato Secondary School (pseudonym). It was conducted with a Grade 10 Physical Science class consisting of 30 learners. To generate data, questionnaires, focus group interviews, lesson observations, stimulated recall interviews, as well as learners’ journal reflections were used. Conceptions, dispositions, interest and sense-making were used as conceptual lenses while Vygotsky’s social constructivism was the theoretical framework that informed this study. Quantitative data were analysed using the conceptual lenses and were subsequently presented in tables and graphs. That is, a deductive approach to analysis was used. On the other hand, a thematic approach was used to analyse the qualitative data. That is, qualitative data were inductively analysed to come up with sub-themes and themes. The findings from this study revealed significant shifts in learners’ conceptions, dispositions and interest towards science after the use of easily accessible resources to do hands-on practical activities. Similarly, learners’ sense-making of science concepts improved. This study thus recommends that science teachers should, where possible, make use of easily accessible resources to carry out hands-on practical activities during their science lessons. During such hands-on practicals, however, emphasis should be on the development of scientific concepts.
- Full Text:
- Date Issued: 2020
An investigation of Wikipedia translation as an additive pedagogy for Oshikwanyama first language learning
- Authors: Hautemo, Aletta Mweneni
- Date: 2014
- Subjects: Kuanyama language -- Study and teaching (Secondary) -- Computer-assisted instruction , Kuanyama language -- Machine translating -- Namibia , Language and languages -- Study and teaching (Secondary) -- Computer-assisted instruction , Computer-assisted instruction -- Study and teaching (Secondary) -- Namibia , Information technology -- Study and teaching (Secondary) -- Namibia , Educational technology -- Namibia , Wikipedia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1982 , http://hdl.handle.net/10962/d1013139
- Description: The integration of Information and Communication Technology in the indigenous language classroom lags behind compared to other subjects. In many ways, indigenous language teachers find it difficult and to some extent, impossible to integrate ICT into their classroom activities. The focus of this study is to explore the ways in which ICT could be used as a learning tool in an Oshikwanyama First Language classroom. I investigated the use of Wikipedia translation as an additional teaching and learning tool. I concentrated on the impact that ICT tools have on learning, and the motivation it has on learners to learn Oshikwanyama. This qualitative case study was conducted in an urban school in northern Namibia. The adoption of ICT at the school is good as there is a full-fledged computer lab with unlimited wireless internet access. This was a requirement for the project to enable the participants to work online. I purposefully chose higher-level learners (Secondary phase) for this study. I conducted a survey with them on their access to and use of ICT devices in their daily lives, and thereafter conducted a basic computer workshop and a Wikipedia translation project with them. My research findings show that although the use of ICT is part of the learners’ lives, most of the communication through ICT devices is done in English not Oshikwanyama. Wikipedia translation offers a stimulating learning platform for learners to learn Oshikwanyama and English at the same time and this improved their performance in both languages. Furthermore, the Wikipedia translation, which was done collaboratively, gave learners the confidence to work with other learners to create knowledge. Lastly, Wikipedia translation motivates learners to learn Oshikwanyama and use it in their daily ICT interaction.
- Full Text:
- Date Issued: 2014
- Authors: Hautemo, Aletta Mweneni
- Date: 2014
- Subjects: Kuanyama language -- Study and teaching (Secondary) -- Computer-assisted instruction , Kuanyama language -- Machine translating -- Namibia , Language and languages -- Study and teaching (Secondary) -- Computer-assisted instruction , Computer-assisted instruction -- Study and teaching (Secondary) -- Namibia , Information technology -- Study and teaching (Secondary) -- Namibia , Educational technology -- Namibia , Wikipedia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1982 , http://hdl.handle.net/10962/d1013139
- Description: The integration of Information and Communication Technology in the indigenous language classroom lags behind compared to other subjects. In many ways, indigenous language teachers find it difficult and to some extent, impossible to integrate ICT into their classroom activities. The focus of this study is to explore the ways in which ICT could be used as a learning tool in an Oshikwanyama First Language classroom. I investigated the use of Wikipedia translation as an additional teaching and learning tool. I concentrated on the impact that ICT tools have on learning, and the motivation it has on learners to learn Oshikwanyama. This qualitative case study was conducted in an urban school in northern Namibia. The adoption of ICT at the school is good as there is a full-fledged computer lab with unlimited wireless internet access. This was a requirement for the project to enable the participants to work online. I purposefully chose higher-level learners (Secondary phase) for this study. I conducted a survey with them on their access to and use of ICT devices in their daily lives, and thereafter conducted a basic computer workshop and a Wikipedia translation project with them. My research findings show that although the use of ICT is part of the learners’ lives, most of the communication through ICT devices is done in English not Oshikwanyama. Wikipedia translation offers a stimulating learning platform for learners to learn Oshikwanyama and English at the same time and this improved their performance in both languages. Furthermore, the Wikipedia translation, which was done collaboratively, gave learners the confidence to work with other learners to create knowledge. Lastly, Wikipedia translation motivates learners to learn Oshikwanyama and use it in their daily ICT interaction.
- Full Text:
- Date Issued: 2014
Bioaccumulation and histopathology of copper in Oreochromis mossambicus
- Authors: Naigaga, Irene
- Date: 2003
- Subjects: Mozambique tilapia , Copper , Marine toxins , Fishes -- Effect of water pollution on , Water -- Pollution -- Environmental aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5234 , http://hdl.handle.net/10962/d1005077 , Mozambique tilapia , Copper , Marine toxins , Fishes -- Effect of water pollution on , Water -- Pollution -- Environmental aspects
- Description: Cu is one of the most toxic elements that affect fish populations when the fish are exposed to concentrations exceeding their tolerance. To investigate the effects of elementary Cu on aspects of bioconcentration, histology and behaviour, O. mossambicus were exposed to 0 and 0.75 ± 0.20 mg/l of Cu for 96 hours (short-term study), and 0, 0.11 ± 0.02, 0.29 ± 0.02, and 0.47 ± 0.04 mg/l of Cu for 64 days (longterm study) under controlled conditions in the laboratory. For the long-term study fish were sampled for gills, liver, and kidney Cu accumulation analysis after 1, 32 and 64 days of exposure and after 1, 2, 4, 16, 32, and 64 days for gills, liver and spleen histology analysis. Cu accumulation was concentration-duration dependent with the highest accumulation capacity in the liver. A multifactor linear model was developed for the relationship between exposure dose, exposure duration and Cu accumulation in the organs with the liver model: Log L = 3.35 + 0.85W + 0.31T (r² = 0.892) giving a better fit than the gills: G = −35.09 + 10.58W + 17.58T (r² = 0.632). Where L = Cu accumulation values in the liver, G = Cu accumulation values in the gills (both in μg/g dry mass); W = exposure dose in water (mg/l); and T = exposure time (days). Using this model Cu accumulation in organs can be estimated when exposure concentration and duration is known. This model should be tested under different conditions to determine the potential of the model in monitoring Cu toxicity in the environment. Lesions were observed in the liver, gills and spleen in all Cu treatments at all exposure concentration and exposure durations. However, the incidence and the degree of alteration was related to the concentration of Cu and duration of exposure. The sequential appearance of lesions in the order of, hepatic vacuolar degeneration, fatty degeneration and necrosis indicated a gradual increase in liver damage with larger duration of exposure time and increasing Cu concentration. The initial lesions in the gills were manifested as hypertrophy and hyperplasia of the gill epithelium causing increase in the thickness of the secondary lamellae, mucous cell hypertrophy and proliferation, mucous hypersecretion, proliferation of eosinophilic granule cells and hyperplasia of interlamellar cells. With increase in exposure time, necrosis of the eosinophilic granule cells, lamellar oedema, epithelial desquamation and increase in severity of lamellar hyperplasia were observed. These lesions indicated an initial defence mechanism of the fish against Cu toxicity followed by advanced histological changes that were related to Cu concentration and duration of exposure. Changes in the spleen were haemosiderosis, increase in the white pulp and macrophage centres, reduction in the red pulp, and necrosis suggesting that fish exposed to environmentally relevant levels of Cu may be histopathologically altered leading to anaemia and immunosuppression. Regression analysis was used to quantify the relationship between the total activity of the fish, and duration of exposure. There was a gradual decline in fish activity related to Cu concentration and duration of exposure before introducing food into the tanks. There was a constant activity after introducing food in the tanks at the control and 0.11 ± 0.02 mg/l Cu exposure levels irrespective of exposure time. Analysis of covariance (ANCOVA) was used to test for the difference in slopes between treatments. There was no significant difference (p > 0.05) between slopes of the control and 0.11 ± 0.02 mg/l Cu, and between 0.29 ± 0.02 and 47 ± 0.04 mg/l Cu before and after introducing food in the tanks. The slopes of both the control and 0.11 ± 0.02 mg/l Cu were significantly different from those of 0.29 ± 0.02 and 0.47 ± 0.04 mg/l Cu (p < 0.05). There were significant differences in the mean opercular movements per minute between treatments (p < 0.05). There was hyperventilation at 0.11 ± 0.02 mg/l Cu i.e. 87 ± 18 opercular movements per minute (mean ± standard deviation) and hypoventilation at 0.29 ± 0.02 and 0.47 ± 0.04 mg/l Cu i.e. 37 ± 34 and 13 ± 6 opercular movements per minute compared to the control. Hypo- and hyperventilation were related to the lesser and greater gill damage, respectively. In conclusion Cu accumulation and effects on histology of the liver, gills and were related to the concentration of Cu in the water and duration of exposure showing a gradual increase in incidence and intensity with larger duration of exposure time and increasing Cu concentration. The fish were initially able to homeostatically regulate and detoxify Cu. However, as the exposure continued, the homeostatic mechanism appears to have failed to cope with the increasing metal burden causing advanced histological changes.
- Full Text:
- Date Issued: 2003
- Authors: Naigaga, Irene
- Date: 2003
- Subjects: Mozambique tilapia , Copper , Marine toxins , Fishes -- Effect of water pollution on , Water -- Pollution -- Environmental aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5234 , http://hdl.handle.net/10962/d1005077 , Mozambique tilapia , Copper , Marine toxins , Fishes -- Effect of water pollution on , Water -- Pollution -- Environmental aspects
- Description: Cu is one of the most toxic elements that affect fish populations when the fish are exposed to concentrations exceeding their tolerance. To investigate the effects of elementary Cu on aspects of bioconcentration, histology and behaviour, O. mossambicus were exposed to 0 and 0.75 ± 0.20 mg/l of Cu for 96 hours (short-term study), and 0, 0.11 ± 0.02, 0.29 ± 0.02, and 0.47 ± 0.04 mg/l of Cu for 64 days (longterm study) under controlled conditions in the laboratory. For the long-term study fish were sampled for gills, liver, and kidney Cu accumulation analysis after 1, 32 and 64 days of exposure and after 1, 2, 4, 16, 32, and 64 days for gills, liver and spleen histology analysis. Cu accumulation was concentration-duration dependent with the highest accumulation capacity in the liver. A multifactor linear model was developed for the relationship between exposure dose, exposure duration and Cu accumulation in the organs with the liver model: Log L = 3.35 + 0.85W + 0.31T (r² = 0.892) giving a better fit than the gills: G = −35.09 + 10.58W + 17.58T (r² = 0.632). Where L = Cu accumulation values in the liver, G = Cu accumulation values in the gills (both in μg/g dry mass); W = exposure dose in water (mg/l); and T = exposure time (days). Using this model Cu accumulation in organs can be estimated when exposure concentration and duration is known. This model should be tested under different conditions to determine the potential of the model in monitoring Cu toxicity in the environment. Lesions were observed in the liver, gills and spleen in all Cu treatments at all exposure concentration and exposure durations. However, the incidence and the degree of alteration was related to the concentration of Cu and duration of exposure. The sequential appearance of lesions in the order of, hepatic vacuolar degeneration, fatty degeneration and necrosis indicated a gradual increase in liver damage with larger duration of exposure time and increasing Cu concentration. The initial lesions in the gills were manifested as hypertrophy and hyperplasia of the gill epithelium causing increase in the thickness of the secondary lamellae, mucous cell hypertrophy and proliferation, mucous hypersecretion, proliferation of eosinophilic granule cells and hyperplasia of interlamellar cells. With increase in exposure time, necrosis of the eosinophilic granule cells, lamellar oedema, epithelial desquamation and increase in severity of lamellar hyperplasia were observed. These lesions indicated an initial defence mechanism of the fish against Cu toxicity followed by advanced histological changes that were related to Cu concentration and duration of exposure. Changes in the spleen were haemosiderosis, increase in the white pulp and macrophage centres, reduction in the red pulp, and necrosis suggesting that fish exposed to environmentally relevant levels of Cu may be histopathologically altered leading to anaemia and immunosuppression. Regression analysis was used to quantify the relationship between the total activity of the fish, and duration of exposure. There was a gradual decline in fish activity related to Cu concentration and duration of exposure before introducing food into the tanks. There was a constant activity after introducing food in the tanks at the control and 0.11 ± 0.02 mg/l Cu exposure levels irrespective of exposure time. Analysis of covariance (ANCOVA) was used to test for the difference in slopes between treatments. There was no significant difference (p > 0.05) between slopes of the control and 0.11 ± 0.02 mg/l Cu, and between 0.29 ± 0.02 and 47 ± 0.04 mg/l Cu before and after introducing food in the tanks. The slopes of both the control and 0.11 ± 0.02 mg/l Cu were significantly different from those of 0.29 ± 0.02 and 0.47 ± 0.04 mg/l Cu (p < 0.05). There were significant differences in the mean opercular movements per minute between treatments (p < 0.05). There was hyperventilation at 0.11 ± 0.02 mg/l Cu i.e. 87 ± 18 opercular movements per minute (mean ± standard deviation) and hypoventilation at 0.29 ± 0.02 and 0.47 ± 0.04 mg/l Cu i.e. 37 ± 34 and 13 ± 6 opercular movements per minute compared to the control. Hypo- and hyperventilation were related to the lesser and greater gill damage, respectively. In conclusion Cu accumulation and effects on histology of the liver, gills and were related to the concentration of Cu in the water and duration of exposure showing a gradual increase in incidence and intensity with larger duration of exposure time and increasing Cu concentration. The fish were initially able to homeostatically regulate and detoxify Cu. However, as the exposure continued, the homeostatic mechanism appears to have failed to cope with the increasing metal burden causing advanced histological changes.
- Full Text:
- Date Issued: 2003
PyMORESANE: A Pythonic and CUDA-accelerated implementation of the MORESANE deconvolution algorithm
- Authors: Kenyon, Jonathan
- Date: 2015
- Subjects: Radio astronomy , Imaging systems in astronomy , MOdel REconstruction by Synthesis-ANalysis Estimators (MORESANE)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5563 , http://hdl.handle.net/10962/d1020098
- Description: The inadequacies of the current generation of deconvolution algorithms are rapidly becoming apparent as new, more sensitive radio interferometers are constructed. In light of these inadequacies, there is renewed interest in the field of deconvolution. Many new algorithms are being developed using the mathematical framework of compressed sensing. One such technique, MORESANE, has recently been shown to be a powerful tool for the recovery of faint difuse emission from synthetic and simulated data. However, the original implementation is not well-suited to large problem sizes due to its computational complexity. Additionally, its use of proprietary software prevents it from being freely distributed and used. This has motivated the development of a freely available Python implementation, PyMORESANE. This thesis describes the implementation of PyMORESANE as well as its subsequent augmentation with MPU and GPGPU code. These additions accelerate the algorithm and thus make it competitive with its legacy counterparts. The acceleration of the algorithm is verified by means of benchmarking tests for varying image size and complexity. Additionally, PyMORESANE is shown to work not only on synthetic data, but on real observational data. This verification means that the MORESANE algorithm, and consequently the PyMORESANE implementation, can be added to the current arsenal of deconvolution tools.
- Full Text:
- Date Issued: 2015
- Authors: Kenyon, Jonathan
- Date: 2015
- Subjects: Radio astronomy , Imaging systems in astronomy , MOdel REconstruction by Synthesis-ANalysis Estimators (MORESANE)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5563 , http://hdl.handle.net/10962/d1020098
- Description: The inadequacies of the current generation of deconvolution algorithms are rapidly becoming apparent as new, more sensitive radio interferometers are constructed. In light of these inadequacies, there is renewed interest in the field of deconvolution. Many new algorithms are being developed using the mathematical framework of compressed sensing. One such technique, MORESANE, has recently been shown to be a powerful tool for the recovery of faint difuse emission from synthetic and simulated data. However, the original implementation is not well-suited to large problem sizes due to its computational complexity. Additionally, its use of proprietary software prevents it from being freely distributed and used. This has motivated the development of a freely available Python implementation, PyMORESANE. This thesis describes the implementation of PyMORESANE as well as its subsequent augmentation with MPU and GPGPU code. These additions accelerate the algorithm and thus make it competitive with its legacy counterparts. The acceleration of the algorithm is verified by means of benchmarking tests for varying image size and complexity. Additionally, PyMORESANE is shown to work not only on synthetic data, but on real observational data. This verification means that the MORESANE algorithm, and consequently the PyMORESANE implementation, can be added to the current arsenal of deconvolution tools.
- Full Text:
- Date Issued: 2015
Development and optimisation of a novel Plasmodium falciparum Hsp90-Hop interaction assay
- Authors: Wambua, Lynn
- Date: 2018
- Subjects: Plasmodium falciparum , Molecular chaperones , Heat shock proteins , Protein-protein interactions , Antimalarials
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62626 , vital:28216
- Description: Protein-protein interactions are involved in a range of disease processes and thus have become the focus of many drug discovery programs. Widespread drug resistance to all currently used antimalarial drugs drives the search for alternative drug targets with novel mechanisms of action that offer new therapeutic options. Molecular chaperones such as heat shock proteins facilitate protein folding, play a role in protein trafficking and prevent protein misfolding in cells under stress. Heat shock protein 90 (Hsp90) is a well-studied chaperone that has been the focus of cancer drug development with moderate success. In Plasmodium falciparum (P. falciparum), heat shock proteins are thought to play a vital role in parasite survival of the physiologically diverse habitats of the parasite lifecycle and because Hsp90 is prominently expressed in P. falciparum, the chaperone is considered a potentially ideal drug target. Hsp90 function in cells is regulated by interactions with co-chaperones, which includes Heat shock protein 70-Heat shock protein 90 organising protein (Hop). As opposed to directly inhibiting Hsp90 activity, targeting Hsp90 interaction with Hop has recently been suggested as an alternative method of Hsp90 inhibition that has not been explored in P. falciparum. The aim of this research project was to demonstrate PfHsp90 and PfHop robustly interact in vitro and to facilitate high-throughput screening of PfHsp90-PfHop inhibitors by developing and optimising a novel plate capture Hsp90-Hop interaction assay. To establish the assay, the respective domains of the proteins that mediate Hsp90-Hop interaction were used (Hsp90 C- terminal domain and Hop TPR2A domain). The human Hsp90 C-terminal domain and glutathione-S-transferase (GST) coding sequences were cloned into pET-28a(+) and murine and P. falciparum TPR2A sequences into pGEX-4T-1 plasmids to enable expression of histidine-tagged and GST fusion proteins, respectively, in Escherichia coli. The P. falciparum Hsp90 C-terminal domain sequence cloned into pET-28a(+) was supplied by GenScript. The constructs were transformed into T7 Express lysYcompetent E. coli cells and subsequent small- scale expression studies showed the recombinant proteins were expressed in a soluble form allowing for subsequent protein purification. Purification of the recombinant proteins was achieved using nickel-NTA and glutathione affinity chromatography for the His-tagged (Hsp90 C-terminal domains and GST) and GST fusion proteins (TPR2A domains), respectively. The purified proteins were used to establish and optimise mammalian and P. falciparum Hsp90- Hop interaction assays on nickel-coated plates by immobilising the His-tagged C-terminal domains on the plates and detecting the binding of the GST-TPR2A domains using a colorimetric GST enzyme assay. Z’-factor values above 0.5 were observed for both assays indicating good separation between the protein interaction signals and negative control background signals, although relatively high background signals were observed for the mammalian interaction due to non-specific binding of murine TPR2A to the plate. Designed human and P. falciparum TPR peptides were observed to be effective inhibitors of the mammalian and P. falciparum interactions, demonstrating the assay’s ability to respond to inhibitor compounds. Comparison of assay performance using GST assay kit reagents and lab- prepared reagents showed the assay was more efficient using lab-prepared reagents, however, lower GST signals were observed when comparing assay performance using a custom prepared Ni-NTA plate to a purchased Ni-NTA plate. The Hsp90-Hop interaction assays were also performed using an alternative assay format in which the GST-TPR2A fusion proteins were immobilised on glutathione-coated plates and binding of the His-tagged C-terminal domains detected with a nickel-horseradish peroxidase (HRP) conjugate and a colorimetric HRP substrate. The assay showed higher interaction signals for the P. falciparum proteins but comparatively low signals for the mammalian proteins. Z’-factor values for the assay were above 0.8 for both protein sets, suggesting this assay format is superior to the GST assay. However, further optimisation of this assay format is required. This study demonstrated direct binding of PfHsp90-PfHop in vitro and established a novel and robust PfHsp90-PfHop interaction assay format that can be used in future screening campaigns.
- Full Text:
- Date Issued: 2018
- Authors: Wambua, Lynn
- Date: 2018
- Subjects: Plasmodium falciparum , Molecular chaperones , Heat shock proteins , Protein-protein interactions , Antimalarials
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/62626 , vital:28216
- Description: Protein-protein interactions are involved in a range of disease processes and thus have become the focus of many drug discovery programs. Widespread drug resistance to all currently used antimalarial drugs drives the search for alternative drug targets with novel mechanisms of action that offer new therapeutic options. Molecular chaperones such as heat shock proteins facilitate protein folding, play a role in protein trafficking and prevent protein misfolding in cells under stress. Heat shock protein 90 (Hsp90) is a well-studied chaperone that has been the focus of cancer drug development with moderate success. In Plasmodium falciparum (P. falciparum), heat shock proteins are thought to play a vital role in parasite survival of the physiologically diverse habitats of the parasite lifecycle and because Hsp90 is prominently expressed in P. falciparum, the chaperone is considered a potentially ideal drug target. Hsp90 function in cells is regulated by interactions with co-chaperones, which includes Heat shock protein 70-Heat shock protein 90 organising protein (Hop). As opposed to directly inhibiting Hsp90 activity, targeting Hsp90 interaction with Hop has recently been suggested as an alternative method of Hsp90 inhibition that has not been explored in P. falciparum. The aim of this research project was to demonstrate PfHsp90 and PfHop robustly interact in vitro and to facilitate high-throughput screening of PfHsp90-PfHop inhibitors by developing and optimising a novel plate capture Hsp90-Hop interaction assay. To establish the assay, the respective domains of the proteins that mediate Hsp90-Hop interaction were used (Hsp90 C- terminal domain and Hop TPR2A domain). The human Hsp90 C-terminal domain and glutathione-S-transferase (GST) coding sequences were cloned into pET-28a(+) and murine and P. falciparum TPR2A sequences into pGEX-4T-1 plasmids to enable expression of histidine-tagged and GST fusion proteins, respectively, in Escherichia coli. The P. falciparum Hsp90 C-terminal domain sequence cloned into pET-28a(+) was supplied by GenScript. The constructs were transformed into T7 Express lysYcompetent E. coli cells and subsequent small- scale expression studies showed the recombinant proteins were expressed in a soluble form allowing for subsequent protein purification. Purification of the recombinant proteins was achieved using nickel-NTA and glutathione affinity chromatography for the His-tagged (Hsp90 C-terminal domains and GST) and GST fusion proteins (TPR2A domains), respectively. The purified proteins were used to establish and optimise mammalian and P. falciparum Hsp90- Hop interaction assays on nickel-coated plates by immobilising the His-tagged C-terminal domains on the plates and detecting the binding of the GST-TPR2A domains using a colorimetric GST enzyme assay. Z’-factor values above 0.5 were observed for both assays indicating good separation between the protein interaction signals and negative control background signals, although relatively high background signals were observed for the mammalian interaction due to non-specific binding of murine TPR2A to the plate. Designed human and P. falciparum TPR peptides were observed to be effective inhibitors of the mammalian and P. falciparum interactions, demonstrating the assay’s ability to respond to inhibitor compounds. Comparison of assay performance using GST assay kit reagents and lab- prepared reagents showed the assay was more efficient using lab-prepared reagents, however, lower GST signals were observed when comparing assay performance using a custom prepared Ni-NTA plate to a purchased Ni-NTA plate. The Hsp90-Hop interaction assays were also performed using an alternative assay format in which the GST-TPR2A fusion proteins were immobilised on glutathione-coated plates and binding of the His-tagged C-terminal domains detected with a nickel-horseradish peroxidase (HRP) conjugate and a colorimetric HRP substrate. The assay showed higher interaction signals for the P. falciparum proteins but comparatively low signals for the mammalian proteins. Z’-factor values for the assay were above 0.8 for both protein sets, suggesting this assay format is superior to the GST assay. However, further optimisation of this assay format is required. This study demonstrated direct binding of PfHsp90-PfHop in vitro and established a novel and robust PfHsp90-PfHop interaction assay format that can be used in future screening campaigns.
- Full Text:
- Date Issued: 2018
Epithermal precious metal deposits physicochemical constraints, classification characteristics and exploration guidelines
- Authors: McIver, Donald A
- Date: 1997
- Subjects: Precious metals , Geothermal resources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4941 , http://hdl.handle.net/10962/d1005553 , Precious metals , Geothermal resources
- Description: Epithermal deposits include a broad range of precious metal, base metal, mercury, and stibnite deposits. These deposits exhibit a low temperature of formation (180-280°C) at pressures of less than a few hundred bars (equivalent to depths of 1.5 - 2.0lkm). Epithermal gold deposits are the product of large-scale hydrothermal systems which mostly occur in convergent plate margin settings. Associated volcanism is largely of andesitic arc (calcalkaline to alkaline), or rhyolitic back-arc type. Porphyry Cu-Mo-Au deposits form deeper in the same systems. Genetic processes within individual deposits take place in an extremely complex manner. The resultant mineral associations, alteration styles and metal deposition patterns are even more complicated. Many attempts have been made to classify epithermal deposits based on mineralogy and alteration, host rocks, deposit form, genetic models, and standard deposits. For the explorationist, the most useful classification schemes should be brief, simple, descriptive, observationally based, and informative. Ultimately, two distinct styles of epithermal gold deposits are readily recognised: high-sulphidation, acid sulphate and low-sulphidation, adularia-sericite types. The terms high-sulphidation (HS) and low-sulphidation (IS) are based on the sulphidation state of associated sulphide minerals, which, along with characteristic hydrothermal alteration, reflect fundamental chemical differences in the epithermal environment. Highsulphidation-type deposits form in the root zones of volcanic domes from acid waters that contain residual magmatic volatiles. The low-sulphidation-type deposits form in geothermal systems where surficial waters mix with deeper, heated saline waters in a lateral flow regime, where neutral to weakly acidic, alkali chloride waters are dominant. The HSILS classification, combined with a simple description of the form of the deposit, conveys a large amount of information on mineralogy, alteration, and spatial characteristics of the mineralisation, and allows inferences to be drawn regarding likely regional controls, and the characteristics of the ore-forming fluids. The modern understanding of these environments allows us to quite effectively identify the most probable foci of mineral deposition in any given district. Current knowledge of these deposits has been derived from studies of active geothermal systems. Through comparison with alteration zones within these systems, the exploration geologist may determine the potential distribution and types of ore in a fossil geothermal system. Alteration zoning specifically can be used as a guide towards the most prospective part of the system. Epithermal gold deposits of both HS- and LS-styles are nevertheless profoundly difficult exploration targets. Successful exploration must rely on the integration of a variety of exploration techniques, guided by an understanding of the characteristics of the deposits and the processes that form them. There are no simple formulae for success in epithermal exploration: what works best must be determined for each terrain and each prospect. On a regional scale tectonic, igneous and structural settings can be used, together with assessment of the depth of erosion, to select areas for project area scale exploration. Integrated geological-geophysical interpretation derived from airborne geophysics providesa basis of targeting potential ore environments for follow-up. Geology, geochemistry and surface geophysics localise mineral concentrations within these target areas
- Full Text:
- Date Issued: 1997
- Authors: McIver, Donald A
- Date: 1997
- Subjects: Precious metals , Geothermal resources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4941 , http://hdl.handle.net/10962/d1005553 , Precious metals , Geothermal resources
- Description: Epithermal deposits include a broad range of precious metal, base metal, mercury, and stibnite deposits. These deposits exhibit a low temperature of formation (180-280°C) at pressures of less than a few hundred bars (equivalent to depths of 1.5 - 2.0lkm). Epithermal gold deposits are the product of large-scale hydrothermal systems which mostly occur in convergent plate margin settings. Associated volcanism is largely of andesitic arc (calcalkaline to alkaline), or rhyolitic back-arc type. Porphyry Cu-Mo-Au deposits form deeper in the same systems. Genetic processes within individual deposits take place in an extremely complex manner. The resultant mineral associations, alteration styles and metal deposition patterns are even more complicated. Many attempts have been made to classify epithermal deposits based on mineralogy and alteration, host rocks, deposit form, genetic models, and standard deposits. For the explorationist, the most useful classification schemes should be brief, simple, descriptive, observationally based, and informative. Ultimately, two distinct styles of epithermal gold deposits are readily recognised: high-sulphidation, acid sulphate and low-sulphidation, adularia-sericite types. The terms high-sulphidation (HS) and low-sulphidation (IS) are based on the sulphidation state of associated sulphide minerals, which, along with characteristic hydrothermal alteration, reflect fundamental chemical differences in the epithermal environment. Highsulphidation-type deposits form in the root zones of volcanic domes from acid waters that contain residual magmatic volatiles. The low-sulphidation-type deposits form in geothermal systems where surficial waters mix with deeper, heated saline waters in a lateral flow regime, where neutral to weakly acidic, alkali chloride waters are dominant. The HSILS classification, combined with a simple description of the form of the deposit, conveys a large amount of information on mineralogy, alteration, and spatial characteristics of the mineralisation, and allows inferences to be drawn regarding likely regional controls, and the characteristics of the ore-forming fluids. The modern understanding of these environments allows us to quite effectively identify the most probable foci of mineral deposition in any given district. Current knowledge of these deposits has been derived from studies of active geothermal systems. Through comparison with alteration zones within these systems, the exploration geologist may determine the potential distribution and types of ore in a fossil geothermal system. Alteration zoning specifically can be used as a guide towards the most prospective part of the system. Epithermal gold deposits of both HS- and LS-styles are nevertheless profoundly difficult exploration targets. Successful exploration must rely on the integration of a variety of exploration techniques, guided by an understanding of the characteristics of the deposits and the processes that form them. There are no simple formulae for success in epithermal exploration: what works best must be determined for each terrain and each prospect. On a regional scale tectonic, igneous and structural settings can be used, together with assessment of the depth of erosion, to select areas for project area scale exploration. Integrated geological-geophysical interpretation derived from airborne geophysics providesa basis of targeting potential ore environments for follow-up. Geology, geochemistry and surface geophysics localise mineral concentrations within these target areas
- Full Text:
- Date Issued: 1997
An investigation into the role of student participation in school governance : a Namibian perspective
- Authors: Shekupakela-Nelulu, Rauna
- Date: 2009
- Subjects: Education and state -- Namibia Education, Secondary -- Namibia Student government -- Namibia Student participation in administration -- Namibia School management and organization -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1923 , http://hdl.handle.net/10962/d1007449
- Description: The issue of student participation in school governance is not a new concept in Namibian schools. Student involvement dates back to the 1970's when the country's administration was under the South African apartheid regime. Back then the involvement of students in school affairs was seen by the regime as a political act and attempts by student leaders to involve themselves in educational issues were often quashed. When the country became independent student representation continued as Student Representative Councils (SRC's), later renamed Learners Representative Councils (LRCs). This study attempted to investigate the perceptions of LRCs and other stakeholders - narnely the school principals and the school board members - of the role of students in school governance. The study was conducted in three Senior Secondary Schools in the Kavango region in Namibia. The research respondents were school principals, chairpersons of the LRCs and one chairperson of a school board. The study was conducted in the interpretive paradigm employing the following three qualitative research methods interviews, observation and document analysis to collect data. Through triangulation it was possible to formulate a rich response to the research question. The study found that, although the notion of student participation in school governance was widely accepted, a number of challenges exist that hamper the effectiveness of LRCs in the schools. It was revealed that there was no national policy docunlent that outlined the roles and function of the LRCs. As a result schools had little direction about the LRCs and subsequently they were given little or no attention by the school authorities. This resulted in misunderstandings and in some cases conflict between learners and the school management. The most significant consequence of these problems was the fact that LRCs were not regarded as true role players in school governance. The study thus recommends that a national policy document that legitimates the role of students in school governance be drafted to provide direction and that schools embark on meaningful training programmes for LRC members. The study also calls for further research to address the gap in literature on this phenomenon, particularly in Namibia.
- Full Text:
- Date Issued: 2009
- Authors: Shekupakela-Nelulu, Rauna
- Date: 2009
- Subjects: Education and state -- Namibia Education, Secondary -- Namibia Student government -- Namibia Student participation in administration -- Namibia School management and organization -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1923 , http://hdl.handle.net/10962/d1007449
- Description: The issue of student participation in school governance is not a new concept in Namibian schools. Student involvement dates back to the 1970's when the country's administration was under the South African apartheid regime. Back then the involvement of students in school affairs was seen by the regime as a political act and attempts by student leaders to involve themselves in educational issues were often quashed. When the country became independent student representation continued as Student Representative Councils (SRC's), later renamed Learners Representative Councils (LRCs). This study attempted to investigate the perceptions of LRCs and other stakeholders - narnely the school principals and the school board members - of the role of students in school governance. The study was conducted in three Senior Secondary Schools in the Kavango region in Namibia. The research respondents were school principals, chairpersons of the LRCs and one chairperson of a school board. The study was conducted in the interpretive paradigm employing the following three qualitative research methods interviews, observation and document analysis to collect data. Through triangulation it was possible to formulate a rich response to the research question. The study found that, although the notion of student participation in school governance was widely accepted, a number of challenges exist that hamper the effectiveness of LRCs in the schools. It was revealed that there was no national policy docunlent that outlined the roles and function of the LRCs. As a result schools had little direction about the LRCs and subsequently they were given little or no attention by the school authorities. This resulted in misunderstandings and in some cases conflict between learners and the school management. The most significant consequence of these problems was the fact that LRCs were not regarded as true role players in school governance. The study thus recommends that a national policy document that legitimates the role of students in school governance be drafted to provide direction and that schools embark on meaningful training programmes for LRC members. The study also calls for further research to address the gap in literature on this phenomenon, particularly in Namibia.
- Full Text:
- Date Issued: 2009
Vocabulary development in a grade 7 class using dictionary skills: an action research project
- Authors: Wells, Stephanie Alice
- Date: 2011
- Subjects: English language -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Vocabulary -- Study and teaching (Elementary) -- South Africa -- Eastern Cape English language Dictionaries -- Polyglot -- Study and teaching (Elementary) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1822 , http://hdl.handle.net/10962/d1003708
- Description: As I was involved as a voluntary, part-time teacher in a local, semi-rural school in the Eastern Cape, South Africa, I became increasingly aware of the learners' lack of English literacy. I therefore decided to do a practical research on vocabulary development, focusing on dictionary skills. In this thesis I describe how I implemented a vocabulary development programme as an Action Research project. My research group was a grade 7 class of English First Additional Language learners who had minimal exposure to English at school and in their communities. The class was a mixture of Afrikaans and isiXhosa home language speakers and the medium of instruction was Afrikaans. The school served a low-income community and was poorly resourced. As dictionary skills is a requirement of the national curriculum, I used 10 time-tabled lessons over a 5 week period to introduce the learners to dictionaries. My data sources were a journal detailing my reflections on each lesson; a video-recording of the lessons; small group interviews after each lesson which were audio-recorded; tasksheets on the work covered in class and questionnaires asking the learners for written responses to the lessons. The class teacher who filmed the lessons was also asked for feedback during and after the programme. My goals were to assess my teaching approach in these circumstances and to what extent the outcomes were positive for the learners. As I had come from a background of English Home Language teaching in good, well-resourced schools I found I had to question many of my assumptions. Although I was an experienced, qualified and confident teacher, I was continually having to reassess my teaching methods which were being challenged by very different classroom conditions. The outcomes of the research show why I was not able to achieve what I had thought I could in the time given.
- Full Text:
- Date Issued: 2011
- Authors: Wells, Stephanie Alice
- Date: 2011
- Subjects: English language -- Study and teaching (Elementary) -- South Africa -- Eastern Cape Vocabulary -- Study and teaching (Elementary) -- South Africa -- Eastern Cape English language Dictionaries -- Polyglot -- Study and teaching (Elementary) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1822 , http://hdl.handle.net/10962/d1003708
- Description: As I was involved as a voluntary, part-time teacher in a local, semi-rural school in the Eastern Cape, South Africa, I became increasingly aware of the learners' lack of English literacy. I therefore decided to do a practical research on vocabulary development, focusing on dictionary skills. In this thesis I describe how I implemented a vocabulary development programme as an Action Research project. My research group was a grade 7 class of English First Additional Language learners who had minimal exposure to English at school and in their communities. The class was a mixture of Afrikaans and isiXhosa home language speakers and the medium of instruction was Afrikaans. The school served a low-income community and was poorly resourced. As dictionary skills is a requirement of the national curriculum, I used 10 time-tabled lessons over a 5 week period to introduce the learners to dictionaries. My data sources were a journal detailing my reflections on each lesson; a video-recording of the lessons; small group interviews after each lesson which were audio-recorded; tasksheets on the work covered in class and questionnaires asking the learners for written responses to the lessons. The class teacher who filmed the lessons was also asked for feedback during and after the programme. My goals were to assess my teaching approach in these circumstances and to what extent the outcomes were positive for the learners. As I had come from a background of English Home Language teaching in good, well-resourced schools I found I had to question many of my assumptions. Although I was an experienced, qualified and confident teacher, I was continually having to reassess my teaching methods which were being challenged by very different classroom conditions. The outcomes of the research show why I was not able to achieve what I had thought I could in the time given.
- Full Text:
- Date Issued: 2011
Family planning : an evaluative study on the attitudes and use of contraceptives by black males in Umtata
- Authors: Madikizela, Nosinodi Alicia
- Date: 1989
- Subjects: Birth control -- South Africa -- Transkei , Transkei (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3278 , http://hdl.handle.net/10962/d1006454 , Birth control -- South Africa -- Transkei , Transkei (South Africa) -- Social conditions
- Description: The purpose of this study is to identify, observe and record the attitudes and use to of contraceptives by black males in Umtata and to investigate the effect of education, urbanisation and age on fertility control. Data was gathered from a sample of adult males who were past the school going age and were employed or working in Umtata and its surburbs, which are Ngangelizwe, Ikwezi, Southernwood, Northcrest, Norwood, Ncambedlana, Nduli Crescent, Fortgale and Hill Crest. Information was also gathered from Nursing officers in charge of family planning service centres in the areas mentioned above. Findings reveal that, although black urbanised educated males in Umtata seem to have accepted the use of contraceptives by themselves and their sexual partners, their patterns of behaviour in relation to fertility control and the value of children to families remains traditional. This contributes to the relatively high fertility rate in the country. Children are an investment for old age. They are also regarded as a security factor against divorce. It is the duty of legally married couples to raise a family with children who will continue to bear the family name. It appears that men are either suspicious of modern contraception if not totally opposed to it. Many still prefer the use of natural methods of contraception. There is thus need for social workers and health planners to recognise and educate males on the use and benefits of modern contraceptives to limit the number of children borne and control periods when they would like to have children. This study will be of value to social welfare services and to family planning nurses who are in direct contact with clients in hospitals and clinics, in their family planning campaigns, when they motivate couples and individuals on the importance of family planning, and also in mother-and-child health services. Educationists, sociologists, psychologists and persons in other fields of study will also benefit from information attained in this survey.
- Full Text:
- Date Issued: 1989
- Authors: Madikizela, Nosinodi Alicia
- Date: 1989
- Subjects: Birth control -- South Africa -- Transkei , Transkei (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3278 , http://hdl.handle.net/10962/d1006454 , Birth control -- South Africa -- Transkei , Transkei (South Africa) -- Social conditions
- Description: The purpose of this study is to identify, observe and record the attitudes and use to of contraceptives by black males in Umtata and to investigate the effect of education, urbanisation and age on fertility control. Data was gathered from a sample of adult males who were past the school going age and were employed or working in Umtata and its surburbs, which are Ngangelizwe, Ikwezi, Southernwood, Northcrest, Norwood, Ncambedlana, Nduli Crescent, Fortgale and Hill Crest. Information was also gathered from Nursing officers in charge of family planning service centres in the areas mentioned above. Findings reveal that, although black urbanised educated males in Umtata seem to have accepted the use of contraceptives by themselves and their sexual partners, their patterns of behaviour in relation to fertility control and the value of children to families remains traditional. This contributes to the relatively high fertility rate in the country. Children are an investment for old age. They are also regarded as a security factor against divorce. It is the duty of legally married couples to raise a family with children who will continue to bear the family name. It appears that men are either suspicious of modern contraception if not totally opposed to it. Many still prefer the use of natural methods of contraception. There is thus need for social workers and health planners to recognise and educate males on the use and benefits of modern contraceptives to limit the number of children borne and control periods when they would like to have children. This study will be of value to social welfare services and to family planning nurses who are in direct contact with clients in hospitals and clinics, in their family planning campaigns, when they motivate couples and individuals on the importance of family planning, and also in mother-and-child health services. Educationists, sociologists, psychologists and persons in other fields of study will also benefit from information attained in this survey.
- Full Text:
- Date Issued: 1989
A standardised protocol for roadkill detection and the determinants of roadkill in the greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa
- Authors: Collinson, Wendy Jane
- Date: 2013
- Subjects: Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5606 , http://hdl.handle.net/10962/d1002056 , Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Description: Despite evidence suggesting that road traffic is a major threat to biodiversity loss, very little is known about its actual impact on wildlife populations in South Africa. Globally, road density and traffic volumes are increasing, and although huge budgets are devoted to the construction and upgrading of roads, there is little or no allocation to mitigation measures for protecting fauna in most countries, particularly Africa. Further, no global standardised protocol exists for the rapid assessment of roadkill or the most economical and efficient approach for assessing roadkill rates. Using vehicle field trials, the reliability of detecting artificially deployed roadkill was assessed. Roadkill detection rates decreased significantly at speeds >50 km/h and were also significantly influenced by light conditions (i.e. detection success was greater when the sun was high) and the position of the roadkill on the road (i.e. smaller roadkill on verges were often missed). These results suggest that roadkill sampling was most effective between 1.5 hours after dawn and 1.5 hours before dusk and that driving at slower speeds (<50 km.h⁻ₑ) was required to detect roadkill. This protocol was implemented across three ecological seasons on a 100 km paved road and a 20 km unpaved road in the Greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa. Driven daily over a 120-day period (three periods consisting each of 40 days), a total of 1,027 roadkill were recorded. These comprised 162 species from all terrestrial vertebrate groups with birds being the most commonly encountered roadkill (50% of all incidents). The high numbers of vertebrates identified as roadkill suggests that road traffic could have potentially unsustainable impacts on wildlife populations and hence the biodiversity of the area. Seventeen variables were identified as possible determinants of roadkill occurrence with season, rainfall, minimum and maximum temperature, habitat type, grass height, grass density, fence type and vehicle type significantly influencing roadkill numbers. Significantly more roadkill were detected on the paved road (9.91/100km) than on the unpaved road (1.8/100km) probably because of greater traffic volumes and the increased speed that vehicles travelled on the paved road. Warmer temperatures and increased rainfall in the preceding 24 hours also increased road mortality numbers as animals tended to become more active during these times. Interestingly, more roadkill was detected in open roadside habitats compared to dense roadside habitats on both the paved and unpaved roads and when grass on the roadside verge was of intermediate height. Open habitat possibly may provide a natural corridor for wildlife which ultimately end up on the road. Roadkill numbers increased when certain other physical barriers, such as cattle fences, were present, probably because these barriers were more penetrable than electric fencing. A series of mitigation measures are proposed to reduce the impacts of roads on wildlife in South Africa. These mitigation measures highlight the need to address the balance between the development of a country’s transport infrastructure and the conservation of its fauna. It is important that research on the impacts of roads becomes standardised to enable robust statistical comparisons which will provide a greater understanding of the potential threats to vertebrate biodiversity
- Full Text:
- Date Issued: 2013
- Authors: Collinson, Wendy Jane
- Date: 2013
- Subjects: Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5606 , http://hdl.handle.net/10962/d1002056 , Roadkill -- South Africa -- Mapungubwe Site , Traffic safety and wildlife -- South Africa -- Mapungubwe Site
- Description: Despite evidence suggesting that road traffic is a major threat to biodiversity loss, very little is known about its actual impact on wildlife populations in South Africa. Globally, road density and traffic volumes are increasing, and although huge budgets are devoted to the construction and upgrading of roads, there is little or no allocation to mitigation measures for protecting fauna in most countries, particularly Africa. Further, no global standardised protocol exists for the rapid assessment of roadkill or the most economical and efficient approach for assessing roadkill rates. Using vehicle field trials, the reliability of detecting artificially deployed roadkill was assessed. Roadkill detection rates decreased significantly at speeds >50 km/h and were also significantly influenced by light conditions (i.e. detection success was greater when the sun was high) and the position of the roadkill on the road (i.e. smaller roadkill on verges were often missed). These results suggest that roadkill sampling was most effective between 1.5 hours after dawn and 1.5 hours before dusk and that driving at slower speeds (<50 km.h⁻ₑ) was required to detect roadkill. This protocol was implemented across three ecological seasons on a 100 km paved road and a 20 km unpaved road in the Greater Mapungubwe Transfrontier Conservation Area, Limpopo Province, South Africa. Driven daily over a 120-day period (three periods consisting each of 40 days), a total of 1,027 roadkill were recorded. These comprised 162 species from all terrestrial vertebrate groups with birds being the most commonly encountered roadkill (50% of all incidents). The high numbers of vertebrates identified as roadkill suggests that road traffic could have potentially unsustainable impacts on wildlife populations and hence the biodiversity of the area. Seventeen variables were identified as possible determinants of roadkill occurrence with season, rainfall, minimum and maximum temperature, habitat type, grass height, grass density, fence type and vehicle type significantly influencing roadkill numbers. Significantly more roadkill were detected on the paved road (9.91/100km) than on the unpaved road (1.8/100km) probably because of greater traffic volumes and the increased speed that vehicles travelled on the paved road. Warmer temperatures and increased rainfall in the preceding 24 hours also increased road mortality numbers as animals tended to become more active during these times. Interestingly, more roadkill was detected in open roadside habitats compared to dense roadside habitats on both the paved and unpaved roads and when grass on the roadside verge was of intermediate height. Open habitat possibly may provide a natural corridor for wildlife which ultimately end up on the road. Roadkill numbers increased when certain other physical barriers, such as cattle fences, were present, probably because these barriers were more penetrable than electric fencing. A series of mitigation measures are proposed to reduce the impacts of roads on wildlife in South Africa. These mitigation measures highlight the need to address the balance between the development of a country’s transport infrastructure and the conservation of its fauna. It is important that research on the impacts of roads becomes standardised to enable robust statistical comparisons which will provide a greater understanding of the potential threats to vertebrate biodiversity
- Full Text:
- Date Issued: 2013
Studies on an autolysin produced by clostridium acetobutylicum
- Authors: Webster, Jocelyn Rowena
- Date: 1981
- Subjects: Clostridium acetobutylicum , Autolysis , Bacteriocins , Proteins -- Synthesis , DNA -- Synthesis , RNA -- Synthesis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3893 , http://hdl.handle.net/10962/d1003724
- Description: An extracellular bacteriocin-like substance produced by Clostridium acetobutylicum was detected during studies on an industrial fermentation process. The bacteriocin-like substance was not inducible by either ultraviolet light or mitomycin C, and its production was not associated with the induction of a protease. Studies on the mode of action of the bacteriocin-like substance indicated that it had no significant effect on DNA, RNA, or protein synthesis, and it did not cause the loss of intracellular ATP. However, the bacteriocin-like substance was able to lyse SDS-treated cells and cell walls of C. acetobutylicum and was identified as an autolysin. Some of the characteristics of this extracellular autolysin were determined, and after purification it was shown to be a glycoprotein with a molecular weight of 28 000.
- Full Text:
- Date Issued: 1981
- Authors: Webster, Jocelyn Rowena
- Date: 1981
- Subjects: Clostridium acetobutylicum , Autolysis , Bacteriocins , Proteins -- Synthesis , DNA -- Synthesis , RNA -- Synthesis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3893 , http://hdl.handle.net/10962/d1003724
- Description: An extracellular bacteriocin-like substance produced by Clostridium acetobutylicum was detected during studies on an industrial fermentation process. The bacteriocin-like substance was not inducible by either ultraviolet light or mitomycin C, and its production was not associated with the induction of a protease. Studies on the mode of action of the bacteriocin-like substance indicated that it had no significant effect on DNA, RNA, or protein synthesis, and it did not cause the loss of intracellular ATP. However, the bacteriocin-like substance was able to lyse SDS-treated cells and cell walls of C. acetobutylicum and was identified as an autolysin. Some of the characteristics of this extracellular autolysin were determined, and after purification it was shown to be a glycoprotein with a molecular weight of 28 000.
- Full Text:
- Date Issued: 1981