The growth characteristics of sparid otoliths
- Authors: Lang, Judy Brenda
- Date: 1992
- Subjects: Fishes -- Age determination , Otoliths , Sparidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5285 , http://hdl.handle.net/10962/d1005129 , Fishes -- Age determination , Otoliths , Sparidae
- Description: The periodicity of formation of growth increments in the otoliths of South African sparids was validated by the oxytetracycline labelling technique. Intramuscular injections of oxytetracycline at a dosage of 250mg/kg marked the otoliths of laboratory held juvenile sparids, while a dosage range of 50 - 100mg/kg oxytetracycline, injected intramuscularly, marked adult sparids in the field. Laboratory held, larval sparid otoliths were marked by immersion for 24hrs a solution of 100-150mg/l alizarin complexone. Both daily (microstructural) and annual (macrostructural) growth increments were identified in the otoliths. The micro incremental pattern of deposition in the sparid otoliths conformed to the general pattern of otolith structure. Sparid otoliths consisted of a central opaque nucleus composed of multiple primordia. surrounding this nucleus were daily increments which decreased in width as the distance from the nucleus increased. Both check rings and subdaily increments were visible throughout the otolith. Minor environmental changes did not affect micro incremental deposition. Narrow opaque and wide hyaline annual growth zones were identified in sectioned sparid otoliths. Scanning electron microscope analysis of the annual growth zones revealed that microincrements within the opaque zone were narrowly spaced with prominent discontinuous phases. This resulted in the greater optical density and higher protein content of the zone. The hyaline zone was composed of widely spaced daily increments with prominent incremental phases accounting for the translucent nature of this zone. Opaque zone formation in the otoliths of many South African sparids was found to occur primarily during periods of reproductive activity and was shown to be indicative of slow otolith growth. The hyaline zone was formed after the spawning season, representative of fast otolith growth. The results of this study have resolved much of the controversy surrounding the rate of growth and time of formation of the opaque and hyaline growth zones in South African sparid otoliths.
- Full Text:
- Date Issued: 1992
- Authors: Lang, Judy Brenda
- Date: 1992
- Subjects: Fishes -- Age determination , Otoliths , Sparidae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5285 , http://hdl.handle.net/10962/d1005129 , Fishes -- Age determination , Otoliths , Sparidae
- Description: The periodicity of formation of growth increments in the otoliths of South African sparids was validated by the oxytetracycline labelling technique. Intramuscular injections of oxytetracycline at a dosage of 250mg/kg marked the otoliths of laboratory held juvenile sparids, while a dosage range of 50 - 100mg/kg oxytetracycline, injected intramuscularly, marked adult sparids in the field. Laboratory held, larval sparid otoliths were marked by immersion for 24hrs a solution of 100-150mg/l alizarin complexone. Both daily (microstructural) and annual (macrostructural) growth increments were identified in the otoliths. The micro incremental pattern of deposition in the sparid otoliths conformed to the general pattern of otolith structure. Sparid otoliths consisted of a central opaque nucleus composed of multiple primordia. surrounding this nucleus were daily increments which decreased in width as the distance from the nucleus increased. Both check rings and subdaily increments were visible throughout the otolith. Minor environmental changes did not affect micro incremental deposition. Narrow opaque and wide hyaline annual growth zones were identified in sectioned sparid otoliths. Scanning electron microscope analysis of the annual growth zones revealed that microincrements within the opaque zone were narrowly spaced with prominent discontinuous phases. This resulted in the greater optical density and higher protein content of the zone. The hyaline zone was composed of widely spaced daily increments with prominent incremental phases accounting for the translucent nature of this zone. Opaque zone formation in the otoliths of many South African sparids was found to occur primarily during periods of reproductive activity and was shown to be indicative of slow otolith growth. The hyaline zone was formed after the spawning season, representative of fast otolith growth. The results of this study have resolved much of the controversy surrounding the rate of growth and time of formation of the opaque and hyaline growth zones in South African sparid otoliths.
- Full Text:
- Date Issued: 1992
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 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
The in-service development of primary school teachers in the use of computers in education with special reference to computer assisted learning: a case study
- Authors: Murray, John Charles
- Date: 1992
- Subjects: Education, Elementary -- South Africa -- Data processing Computer-assisted instruction Teachers -- In-service training -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1572 , http://hdl.handle.net/10962/d1003454
- Description: Many white primary schools in South Africa have acquired computers which are being used in various ways. In my experience few members of staff are confident enough to use the computers in the school for educational purposes. Those who have been using them, generally have been doing computer literacy. The teachers in our school expressed the view that they would like to be able to use the computer, but that they lack the necessary skills and therefore would welcome some form of training. In my opinion computers should form an integral part of a child's learning environment. It has, for some time formed a part of his social environment, either in the home or in the workplace. For computers to be used effectively in the classroom, it follows that the teachers need to be trained to use them. In an attempt to overcome this problem, I designed and presented an in-service course, which used selected computer assisted learning (CAL) programs with teachers. These teachers then used these programs with the pupils in their class and evaluated the pupils' reactions to the innovation. As a result of the observations and the feedback provided by the sample of teachers, it is suggested that this might be a possible approach to in-service training for other schools. With adaptation it should be possible to follow this approach in any school which has a computer and someone on the staff who is willing to take the initiative to implement such an innovation.
- Full Text:
- Date Issued: 1992
- Authors: Murray, John Charles
- Date: 1992
- Subjects: Education, Elementary -- South Africa -- Data processing Computer-assisted instruction Teachers -- In-service training -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1572 , http://hdl.handle.net/10962/d1003454
- Description: Many white primary schools in South Africa have acquired computers which are being used in various ways. In my experience few members of staff are confident enough to use the computers in the school for educational purposes. Those who have been using them, generally have been doing computer literacy. The teachers in our school expressed the view that they would like to be able to use the computer, but that they lack the necessary skills and therefore would welcome some form of training. In my opinion computers should form an integral part of a child's learning environment. It has, for some time formed a part of his social environment, either in the home or in the workplace. For computers to be used effectively in the classroom, it follows that the teachers need to be trained to use them. In an attempt to overcome this problem, I designed and presented an in-service course, which used selected computer assisted learning (CAL) programs with teachers. These teachers then used these programs with the pupils in their class and evaluated the pupils' reactions to the innovation. As a result of the observations and the feedback provided by the sample of teachers, it is suggested that this might be a possible approach to in-service training for other schools. With adaptation it should be possible to follow this approach in any school which has a computer and someone on the staff who is willing to take the initiative to implement such an innovation.
- Full Text:
- Date Issued: 1992
A strategy for promoting computer literacy in staff and students of a teacher training institution : a case study
- Authors: Keep, Joan Diane
- Date: 1992
- Subjects: Computer literacy Computer-assisted instruction Teachers -- Training of -- Data processing
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1773 , http://hdl.handle.net/10962/d1003658
- Description: A case study carried out at Edgewood College of Education (Natal) attempted to demonstrate how in-house training could provide staff with the necessary computer literacy skills to integrate computer technology into lecturing and teaching programmes. The duration of the project was six months and during this time a group of thirty academic staff members were exposed to computer technology via practical experience, lectures and demonstrations. The results gleaned from the project show that most of the staff involved in the project developed sufficient computer skills to be of benefit in their professional and personal tasks. In addition the recognition of the value of word processing and desk top publishing led to the staff encouraging students to use these software packages in the preparation of coursework. Consequently the use of the computer resources increased noticeably in the six month period. One of the goals of the study was to show how staff, once computer literate, would make use of generic software to integrate computer technology into their lecturing programmes. This did not happen and the reasons for this failure are discussed.
- Full Text:
- Date Issued: 1992
- Authors: Keep, Joan Diane
- Date: 1992
- Subjects: Computer literacy Computer-assisted instruction Teachers -- Training of -- Data processing
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1773 , http://hdl.handle.net/10962/d1003658
- Description: A case study carried out at Edgewood College of Education (Natal) attempted to demonstrate how in-house training could provide staff with the necessary computer literacy skills to integrate computer technology into lecturing and teaching programmes. The duration of the project was six months and during this time a group of thirty academic staff members were exposed to computer technology via practical experience, lectures and demonstrations. The results gleaned from the project show that most of the staff involved in the project developed sufficient computer skills to be of benefit in their professional and personal tasks. In addition the recognition of the value of word processing and desk top publishing led to the staff encouraging students to use these software packages in the preparation of coursework. Consequently the use of the computer resources increased noticeably in the six month period. One of the goals of the study was to show how staff, once computer literate, would make use of generic software to integrate computer technology into their lecturing programmes. This did not happen and the reasons for this failure are discussed.
- Full Text:
- Date Issued: 1992
Exploration for stratabound copper, lead and zinc deposits in the Damara-Katanga orogen, central-southern Africa
- Authors: Latorre, J J
- Date: 1992
- Subjects: Mining geology -- Research -- Africa , Copper ores -- Africa , Lead ores -- Africa , Zinc ores -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4946 , http://hdl.handle.net/10962/d1005558
- Description: The Damara-Katanga orogen in central-southern Africa represents an area of 1.73xl0⁶ sq. km. The region is considered one of the wealthiest metallogenic provinces in the world. Successful exploration for stratabound base-metal deposits has taken place at this particular area since the introduction of more organised methodology in the early 1920s. The genesis, location and distribution of the ore deposits are related to their tectonic settings. Geodynamic evolution of the orogen, which initially formed part of a complex Pan-African rift system, comprises the following stages rifting; downwarping, including spreading on the western portion; syn-orogeny and late-orogeny. Two major tectonic events in the history of the region have been identified: the Katangan (900-750 Ma) and the Damaran episodes (750-500 Ma). Timing of mineralisation of ore deposits has been related to the evolutionary stages of the orogen. Genetic models of the most productive deposits are briefly discussed in this dissertation. The sedimentological, geochemical, paleogeographic and structural features can be employed as geological guidelines for integrated exploration programmes. Discoveries of major deposits and prospects in the orogen are also summarised, focussing on the exploration methods employed. The cost-effective use of the exploration techniques includes the classical copper-lead-zinc soil sampling for residual soils such as those in the Copperbelt area. Airborne magnetics and electromagnetics and follow-up ground geophysics have proved successful in areas where the cover is transported in the search for shallow ore deposits such as the Matchless massive sulphides. Remote sensing, geochemical and geophysical techniques have been tried in covered areas of western Botswana. The lack of geological control makes this interpretation difficult. A detailed geological mapping and the use of geochemical and geophysical techniques has been used to delineate carbonate-hosted base-metal deposits at the Otavi Land. The more expensive traditional methods necessary for the delineation of orebodies, such as pitting, trenching and drilling, are also discussed. Using a sequential approach, a possible exploration strategy is suggested, outlining the cost-effective use of remote sensing, geochemical and geophysical techniques. Standardisation in basic geological information is required for future successful explorations in the Damara-Katanga orogen, as well as attractive mining policies. In the event of their implementation, exploration perspectives are promising, specifically in terms of ore potential.
- Full Text:
- Date Issued: 1992
- Authors: Latorre, J J
- Date: 1992
- Subjects: Mining geology -- Research -- Africa , Copper ores -- Africa , Lead ores -- Africa , Zinc ores -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4946 , http://hdl.handle.net/10962/d1005558
- Description: The Damara-Katanga orogen in central-southern Africa represents an area of 1.73xl0⁶ sq. km. The region is considered one of the wealthiest metallogenic provinces in the world. Successful exploration for stratabound base-metal deposits has taken place at this particular area since the introduction of more organised methodology in the early 1920s. The genesis, location and distribution of the ore deposits are related to their tectonic settings. Geodynamic evolution of the orogen, which initially formed part of a complex Pan-African rift system, comprises the following stages rifting; downwarping, including spreading on the western portion; syn-orogeny and late-orogeny. Two major tectonic events in the history of the region have been identified: the Katangan (900-750 Ma) and the Damaran episodes (750-500 Ma). Timing of mineralisation of ore deposits has been related to the evolutionary stages of the orogen. Genetic models of the most productive deposits are briefly discussed in this dissertation. The sedimentological, geochemical, paleogeographic and structural features can be employed as geological guidelines for integrated exploration programmes. Discoveries of major deposits and prospects in the orogen are also summarised, focussing on the exploration methods employed. The cost-effective use of the exploration techniques includes the classical copper-lead-zinc soil sampling for residual soils such as those in the Copperbelt area. Airborne magnetics and electromagnetics and follow-up ground geophysics have proved successful in areas where the cover is transported in the search for shallow ore deposits such as the Matchless massive sulphides. Remote sensing, geochemical and geophysical techniques have been tried in covered areas of western Botswana. The lack of geological control makes this interpretation difficult. A detailed geological mapping and the use of geochemical and geophysical techniques has been used to delineate carbonate-hosted base-metal deposits at the Otavi Land. The more expensive traditional methods necessary for the delineation of orebodies, such as pitting, trenching and drilling, are also discussed. Using a sequential approach, a possible exploration strategy is suggested, outlining the cost-effective use of remote sensing, geochemical and geophysical techniques. Standardisation in basic geological information is required for future successful explorations in the Damara-Katanga orogen, as well as attractive mining policies. In the event of their implementation, exploration perspectives are promising, specifically in terms of ore potential.
- Full Text:
- Date Issued: 1992
The culture of Dunaliella salina and the production of β-carotene in tannery effluents
- Authors: Laubscher, Richard Keith
- Date: 1992
- Subjects: Dunaliella , Carotenes , Tanneries -- Waste disposal , Recycling (Waste, etc.)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4055 , http://hdl.handle.net/10962/d1004116 , Dunaliella , Carotenes , Tanneries -- Waste disposal , Recycling (Waste, etc.)
- Description: The problems of waste disposal in the tanning industry are unique in that the effluents are highly saline, have a high organic loading and contain heavy metals. Methods are available for the safe treatment and disposal of the latter two components, but the saline component requires the expensive outlay of evaporation ponds. This study has identified a possible use for the saline effluents, turning a problematic waste product into a potentially valuable by-product. A range of tannery effluents were identified and tested for their suitability for the mass cultivation of Dunaliella salina (bardawil strain). The bardawil strain was preferred over a local isolate because of its higher production of β-carotene. Ponded tannery effluents and combined processes effluent proved unsuitable for realistic propagation of the alga. Anaerobic digestion of combined processes effluent did not improve its suitability significantly. Anaerobic digestion of hide-soak effluent may remove persistent antimicrobial agents which influence algal growth, but its contribution to enhancing algal growth is equivocal. Undigested hide-soak effluent lacking in persistent antimicrobial agents was found to be an ideal culture medium, as no additional nutrients needed to be added. Significantly higher biomass was obtained in this effluent compared to chemically defined media. Induction of β-carotene was achieved in nitrogen-deficient defined media after culture in tannery effluent. This suggests that a two-stage system using hide-soak effluent for cell propagation and nitrogen deficient media for β-carotene induction, could be possible for the mass cultivation of D. salina for β-carotene production.
- Full Text:
- Date Issued: 1992
- Authors: Laubscher, Richard Keith
- Date: 1992
- Subjects: Dunaliella , Carotenes , Tanneries -- Waste disposal , Recycling (Waste, etc.)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4055 , http://hdl.handle.net/10962/d1004116 , Dunaliella , Carotenes , Tanneries -- Waste disposal , Recycling (Waste, etc.)
- Description: The problems of waste disposal in the tanning industry are unique in that the effluents are highly saline, have a high organic loading and contain heavy metals. Methods are available for the safe treatment and disposal of the latter two components, but the saline component requires the expensive outlay of evaporation ponds. This study has identified a possible use for the saline effluents, turning a problematic waste product into a potentially valuable by-product. A range of tannery effluents were identified and tested for their suitability for the mass cultivation of Dunaliella salina (bardawil strain). The bardawil strain was preferred over a local isolate because of its higher production of β-carotene. Ponded tannery effluents and combined processes effluent proved unsuitable for realistic propagation of the alga. Anaerobic digestion of combined processes effluent did not improve its suitability significantly. Anaerobic digestion of hide-soak effluent may remove persistent antimicrobial agents which influence algal growth, but its contribution to enhancing algal growth is equivocal. Undigested hide-soak effluent lacking in persistent antimicrobial agents was found to be an ideal culture medium, as no additional nutrients needed to be added. Significantly higher biomass was obtained in this effluent compared to chemically defined media. Induction of β-carotene was achieved in nitrogen-deficient defined media after culture in tannery effluent. This suggests that a two-stage system using hide-soak effluent for cell propagation and nitrogen deficient media for β-carotene induction, could be possible for the mass cultivation of D. salina for β-carotene production.
- Full Text:
- Date Issued: 1992
Regulation of the indoleamines by sex steroids
- Authors: Awah, Edmund Kpabi
- Date: 1992
- Subjects: Steroids -- Research , Steroid drugs -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4053 , http://hdl.handle.net/10962/d1004114 , Steroids -- Research , Steroid drugs -- Research
- Description: Alteration of serum tryptophan leads to parallel alterations in brain tryptophan levels. Such changes in brain tryptophan levels has been shown to lead to mood disturbances. The primary enzyme responsible for altering serum tryptophan levels is the liver cytosolic enzyme, tryptophan pyrrolase. Activation of this enzyme is responsible for the enhanced catabolism of circulating tryptophan. The purpose of the present study was firstly to establish whether there is a link between sex steroids and tryptophan pyrrolase activity especially since sex steroids are also known to cause mood disturbances and secondly to determine the effects of sex steroids on brain indolamine metabolism. The results show that all three sex steroids induce the activity of tryptophan pyrrolase implying that they decrease serum tryptophan levels by the activation of tryptophan pyrrolase, thus making less tryptophan available for uptake by the brain. It was also shown that the sex steroids enhance the uptake of ¹⁴C-tryptophan by brain synatopsomes. In addition, the sex steroids influenced the pattern of metabolism of serotonin by organ cultures of rat pineal glands. It is possible that the sex steroids regulate the availability and uptake of indoleamines in the brain.
- Full Text:
- Date Issued: 1992
- Authors: Awah, Edmund Kpabi
- Date: 1992
- Subjects: Steroids -- Research , Steroid drugs -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4053 , http://hdl.handle.net/10962/d1004114 , Steroids -- Research , Steroid drugs -- Research
- Description: Alteration of serum tryptophan leads to parallel alterations in brain tryptophan levels. Such changes in brain tryptophan levels has been shown to lead to mood disturbances. The primary enzyme responsible for altering serum tryptophan levels is the liver cytosolic enzyme, tryptophan pyrrolase. Activation of this enzyme is responsible for the enhanced catabolism of circulating tryptophan. The purpose of the present study was firstly to establish whether there is a link between sex steroids and tryptophan pyrrolase activity especially since sex steroids are also known to cause mood disturbances and secondly to determine the effects of sex steroids on brain indolamine metabolism. The results show that all three sex steroids induce the activity of tryptophan pyrrolase implying that they decrease serum tryptophan levels by the activation of tryptophan pyrrolase, thus making less tryptophan available for uptake by the brain. It was also shown that the sex steroids enhance the uptake of ¹⁴C-tryptophan by brain synatopsomes. In addition, the sex steroids influenced the pattern of metabolism of serotonin by organ cultures of rat pineal glands. It is possible that the sex steroids regulate the availability and uptake of indoleamines in the brain.
- Full Text:
- Date Issued: 1992
The evaluation of an individualised language programme in two multicultural Standard 9 classes : a pilot study
- Authors: Hartman, Lorraine Mary
- Date: 1992
- Subjects: English language -- Study and teaching (Secondary) -- South Africa English language -- Study and teaching (Secondary) -- South Africa -- Foreign speakers Language and education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1523 , http://hdl.handle.net/10962/d1003405
- Description: Two multicultural, mixed-ability Standard Nine classes (17 year olds) were selected for this pilot study. As they were half way through the Senior Secondary phase they had completed most of their English Language syllabus. There was a wide range of achievement in English in addition to which, fifteen of the thirty-nine pupils were English second language speakers. The teacher had to decide how to cope adequately with these differences in the subject English in general and in particular, in the Language component. A Language programme was devised, based on the prescribed textbooks. The pupils could work through the programme at their own pace and order and could consult the researcher during or after class time. The programme only covered the prescribed Language Study component and only a quarter of the total English time during an eight-week period (one term) was given to its completion. A Pre-test was set, the Senior Certificate Language examination paper of 1986, and the results analysed. The two classes were combined into one group and then randomly placed in the experimental and control groups apart from eight boys whose timetable requirements restricted them to being in the same group. The experimental and control groups were not matched. Aspects of Action Research were included in the design; pupils kept individual records; diaries were written by three pupils from each group and an independent observation was made of each group. A Post-test was administered (the 1989 Human Sciences Research Council examination) and this was followed by a questionnaire. The hypothesis, stated in null form, was: Pupils taught by individualised methods will not achieve better results than those taught by traditional methods. This hypothesis proved to be true. The experimental group, who achieved a better result in the pre-test maintained their lead over the control group but did not increase it. Neither group fared well on the post-test but the experimental group achieved a result slightly higher than the provincial average. The affective results were more positive, most pupils enjoying their autonomy and experiencing a sense of achievement despite their results in the post-test. A few preferred whole and small-group teaching, showing that the teacher needs to present the subject in more than one style. This small-scale experiment dealt only with one aspect of English teaching, but there is potential for development particularly with regard to the use of individualised programmes both for remedial and enrichment purposes. The innovative teacher in the multicultural classroom could use individualised programmes profitably as part of his teaching repertoire.
- Full Text:
- Date Issued: 1992
- Authors: Hartman, Lorraine Mary
- Date: 1992
- Subjects: English language -- Study and teaching (Secondary) -- South Africa English language -- Study and teaching (Secondary) -- South Africa -- Foreign speakers Language and education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1523 , http://hdl.handle.net/10962/d1003405
- Description: Two multicultural, mixed-ability Standard Nine classes (17 year olds) were selected for this pilot study. As they were half way through the Senior Secondary phase they had completed most of their English Language syllabus. There was a wide range of achievement in English in addition to which, fifteen of the thirty-nine pupils were English second language speakers. The teacher had to decide how to cope adequately with these differences in the subject English in general and in particular, in the Language component. A Language programme was devised, based on the prescribed textbooks. The pupils could work through the programme at their own pace and order and could consult the researcher during or after class time. The programme only covered the prescribed Language Study component and only a quarter of the total English time during an eight-week period (one term) was given to its completion. A Pre-test was set, the Senior Certificate Language examination paper of 1986, and the results analysed. The two classes were combined into one group and then randomly placed in the experimental and control groups apart from eight boys whose timetable requirements restricted them to being in the same group. The experimental and control groups were not matched. Aspects of Action Research were included in the design; pupils kept individual records; diaries were written by three pupils from each group and an independent observation was made of each group. A Post-test was administered (the 1989 Human Sciences Research Council examination) and this was followed by a questionnaire. The hypothesis, stated in null form, was: Pupils taught by individualised methods will not achieve better results than those taught by traditional methods. This hypothesis proved to be true. The experimental group, who achieved a better result in the pre-test maintained their lead over the control group but did not increase it. Neither group fared well on the post-test but the experimental group achieved a result slightly higher than the provincial average. The affective results were more positive, most pupils enjoying their autonomy and experiencing a sense of achievement despite their results in the post-test. A few preferred whole and small-group teaching, showing that the teacher needs to present the subject in more than one style. This small-scale experiment dealt only with one aspect of English teaching, but there is potential for development particularly with regard to the use of individualised programmes both for remedial and enrichment purposes. The innovative teacher in the multicultural classroom could use individualised programmes profitably as part of his teaching repertoire.
- Full Text:
- Date Issued: 1992
Working with the contemptuous client in psychotherapy
- Authors: Hoffman, Elan
- Date: 1992
- Subjects: Psychotherapist and patient -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3213 , http://hdl.handle.net/10962/d1012315 , Psychotherapist and patient -- Case studies
- Description: The purpose of this case study is to explore the issue of contempt in the therapeutic relationship. The aims are twofold; namely, to illustrate to what extent the case studied throws light on existing theories on contempt in psychotherapy, and to enquire about which stance adopted by the therapist is most appropriate in the therapeutic interaction with a contemptuous client. It investigates the validity of using the case study method in examining both the content and the process of this particular course of psychotherapy. Literature on contempt in psychotherapy is reviewed, as well as the foundation-stone on which it rests, namely, the Kleinian approach to envy . The concepts of the superego and false self are also drawn upon in understanding this particular client's dynamics. The client's therapy is then presented and explored, in order to gain insight into how a psychotherapist's understanding of the contemptuous client can clarify the process of therapy. It highlights the limitations and potentialities that exist in working in this sphere of resistance, and raises questions relevant to therapists faced with these clients. The case study shows how theory in this area is helpful in understanding the contemptuous client, and that the ability of the therapist to endure and survive the contempt of the client is a crucial factor in working with the contemptuous individual.
- Full Text:
- Date Issued: 1992
- Authors: Hoffman, Elan
- Date: 1992
- Subjects: Psychotherapist and patient -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3213 , http://hdl.handle.net/10962/d1012315 , Psychotherapist and patient -- Case studies
- Description: The purpose of this case study is to explore the issue of contempt in the therapeutic relationship. The aims are twofold; namely, to illustrate to what extent the case studied throws light on existing theories on contempt in psychotherapy, and to enquire about which stance adopted by the therapist is most appropriate in the therapeutic interaction with a contemptuous client. It investigates the validity of using the case study method in examining both the content and the process of this particular course of psychotherapy. Literature on contempt in psychotherapy is reviewed, as well as the foundation-stone on which it rests, namely, the Kleinian approach to envy . The concepts of the superego and false self are also drawn upon in understanding this particular client's dynamics. The client's therapy is then presented and explored, in order to gain insight into how a psychotherapist's understanding of the contemptuous client can clarify the process of therapy. It highlights the limitations and potentialities that exist in working in this sphere of resistance, and raises questions relevant to therapists faced with these clients. The case study shows how theory in this area is helpful in understanding the contemptuous client, and that the ability of the therapist to endure and survive the contempt of the client is a crucial factor in working with the contemptuous individual.
- Full Text:
- Date Issued: 1992
Reform and democracy in Mozambique, 1983-1991
- Authors: Morgan, Glenda Nadine
- Date: 1992
- Subjects: Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2809 , http://hdl.handle.net/10962/d1003019 , Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
- Description: Africa is currently experiencing a movement toward more democratic systems of government. The causes of such changes are numerous, but the literature on African democratization, like that on similar changes elsewhere in the world, places emphasis on the role of internal or domestic factors. The role of international pressures toward democratization is almost completely ignored. The case of Mozambique illustrates the dangers of such an omission. During the past decade Mozambique has undergone considerable political change. The single-party, Marxist-Leninist oriented state has been replaced by a multi-party system, devoid of explicit references to any guiding ideology. The government has also expanded its contacts with the West, particularly by means of its assuming membership of the International Monetary Fund and the World Bank. These changes in Mozambique's political orientation have been accompanied by economic reforms, designed to arrest the precipitous decline in the Mozambican economy. In this dissertation I argue that the causes of both the economic and political reforms lie in this decline and in the government's need to secure capital and debt relief internationally. In order to do this, the Mozambican government had to change the aspects of its political system which were seen as being unacceptable by the West, in particular the lack of multi-party competition and its overtly Marxist orientation and close ties to socialist countries. Because the reforms had their primary genesis in Mozambique's need for international acceptance and not in the growth of popularly based democratic organisations, the reforms are fragile and their meaningfulness questionable.
- Full Text:
- Date Issued: 1992
- Authors: Morgan, Glenda Nadine
- Date: 1992
- Subjects: Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2809 , http://hdl.handle.net/10962/d1003019 , Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
- Description: Africa is currently experiencing a movement toward more democratic systems of government. The causes of such changes are numerous, but the literature on African democratization, like that on similar changes elsewhere in the world, places emphasis on the role of internal or domestic factors. The role of international pressures toward democratization is almost completely ignored. The case of Mozambique illustrates the dangers of such an omission. During the past decade Mozambique has undergone considerable political change. The single-party, Marxist-Leninist oriented state has been replaced by a multi-party system, devoid of explicit references to any guiding ideology. The government has also expanded its contacts with the West, particularly by means of its assuming membership of the International Monetary Fund and the World Bank. These changes in Mozambique's political orientation have been accompanied by economic reforms, designed to arrest the precipitous decline in the Mozambican economy. In this dissertation I argue that the causes of both the economic and political reforms lie in this decline and in the government's need to secure capital and debt relief internationally. In order to do this, the Mozambican government had to change the aspects of its political system which were seen as being unacceptable by the West, in particular the lack of multi-party competition and its overtly Marxist orientation and close ties to socialist countries. Because the reforms had their primary genesis in Mozambique's need for international acceptance and not in the growth of popularly based democratic organisations, the reforms are fragile and their meaningfulness questionable.
- Full Text:
- Date Issued: 1992
Images of a changing frontier worldview in Eastern Cape art from Bushman rock art to 1875
- Authors: Cosser, Marijke
- Date: 1992
- Subjects: Art, San , Rock paintings -- South Africa , Art, South African -- 19th century , Art -- South Africa -- History , Painters -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2400 , http://hdl.handle.net/10962/d1002196 , Art, San , Rock paintings -- South Africa , Art, South African -- 19th century , Art -- South Africa -- History , Painters -- South Africa
- Description: A discussion of the concept of worldview shows that how an artist conceives the world in his images is governed by his worldview - an amalgam of the worldview of the group of which he is a part modified by his own ideas, beliefs, attitudes, perceptions and upbringing. The author proposes that studying an artist's work can reveal his, and hence his group's, worldview and thus the attitudes prevalent when the work was produced. A brief historical sketch of the Eastern Cape to 1834 introduces the various settlers in the area. Though no known examples of Black, Boer or Khoi pictorial art are extant, both the Bushmen and the British left such records. A short analysis of rock art shows how the worldview of the Bushman is inherent in their images which reflect man's world as seen with the "inner" eye of the spirit. In white settler art, the author submits that spatial relationships changed in response to a growing confidence as the "savage" land was "civilised" and that the position, pose and size of figures - and the inclusion or exclusion of certain groups - reflect socio-political changes. The two foremost nineteenth-century Eastern Cape artists, Thomas Baines and Frederick I'Ons, succeeded in capturing the atmosphere of Frontier life but are shown to interpret their surroundings through the rose-tinted spectacles of British Romanticism. They also reveal individuality in approach - Baines preferring expansive views while I'Ons's landscapes tend to be "closed-in", strictly following the coulisse scheme of Picturesque painting. Perhaps, the author postulates, such differences result from the very different environments, i.e. Norfolk and London, in which the two grew up. I'Ons is shown typically to use generalised landscapes as backdrops for his foreground figures, while comparing Baines's scenes with modern photographs shows that he adjusted the spacial elements of the topography as well as the temporal sequence of events to suit aesthetic considerations. Lithographed reports of his work contain even further adjustments. The author concludes that the use of Africana art as historical records must be treated with great caution.
- Full Text:
- Date Issued: 1992
- Authors: Cosser, Marijke
- Date: 1992
- Subjects: Art, San , Rock paintings -- South Africa , Art, South African -- 19th century , Art -- South Africa -- History , Painters -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2400 , http://hdl.handle.net/10962/d1002196 , Art, San , Rock paintings -- South Africa , Art, South African -- 19th century , Art -- South Africa -- History , Painters -- South Africa
- Description: A discussion of the concept of worldview shows that how an artist conceives the world in his images is governed by his worldview - an amalgam of the worldview of the group of which he is a part modified by his own ideas, beliefs, attitudes, perceptions and upbringing. The author proposes that studying an artist's work can reveal his, and hence his group's, worldview and thus the attitudes prevalent when the work was produced. A brief historical sketch of the Eastern Cape to 1834 introduces the various settlers in the area. Though no known examples of Black, Boer or Khoi pictorial art are extant, both the Bushmen and the British left such records. A short analysis of rock art shows how the worldview of the Bushman is inherent in their images which reflect man's world as seen with the "inner" eye of the spirit. In white settler art, the author submits that spatial relationships changed in response to a growing confidence as the "savage" land was "civilised" and that the position, pose and size of figures - and the inclusion or exclusion of certain groups - reflect socio-political changes. The two foremost nineteenth-century Eastern Cape artists, Thomas Baines and Frederick I'Ons, succeeded in capturing the atmosphere of Frontier life but are shown to interpret their surroundings through the rose-tinted spectacles of British Romanticism. They also reveal individuality in approach - Baines preferring expansive views while I'Ons's landscapes tend to be "closed-in", strictly following the coulisse scheme of Picturesque painting. Perhaps, the author postulates, such differences result from the very different environments, i.e. Norfolk and London, in which the two grew up. I'Ons is shown typically to use generalised landscapes as backdrops for his foreground figures, while comparing Baines's scenes with modern photographs shows that he adjusted the spacial elements of the topography as well as the temporal sequence of events to suit aesthetic considerations. Lithographed reports of his work contain even further adjustments. The author concludes that the use of Africana art as historical records must be treated with great caution.
- Full Text:
- Date Issued: 1992
The exploitation of methane from landfill
- Authors: Schütte, Renate
- Date: 1992
- Subjects: Methane , Waste products as fuel , Refuse as fuel , Sanitary landfills -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4530 , http://hdl.handle.net/10962/d1015949
- Description: A review of literature on the subject of methane exploitation from landfill is presented in conjunction with the results of experiments concerning landfill gas extraction at the Grahamstown Landfill Site. A description of the LFG extraction system and the utilisation of LFG at the Grahamstown Landfill Site is included. Data concerning LFG enhancement parameters, LFG compositions and flow rates, refuse composition, LFG modelling, LFG pumping trials and the economics of LFG extraction and utilisation are presented. The indication is that LFG can be economically extracted and utilised as a heating fuel in South Africa.
- Full Text:
- Date Issued: 1992
- Authors: Schütte, Renate
- Date: 1992
- Subjects: Methane , Waste products as fuel , Refuse as fuel , Sanitary landfills -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4530 , http://hdl.handle.net/10962/d1015949
- Description: A review of literature on the subject of methane exploitation from landfill is presented in conjunction with the results of experiments concerning landfill gas extraction at the Grahamstown Landfill Site. A description of the LFG extraction system and the utilisation of LFG at the Grahamstown Landfill Site is included. Data concerning LFG enhancement parameters, LFG compositions and flow rates, refuse composition, LFG modelling, LFG pumping trials and the economics of LFG extraction and utilisation are presented. The indication is that LFG can be economically extracted and utilised as a heating fuel in South Africa.
- Full Text:
- Date Issued: 1992
The effects of a 160 km run on selected anthropometric, physiological and psychological parameters
- Authors: Oltmann, Carmen
- Date: 1992
- Subjects: Marathon running -- Psychological effects , Marathon running -- Physiological effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5148 , http://hdl.handle.net/10962/d1009706 , Marathon running -- Psychological effects , Marathon running -- Physiological effects
- Description: Twenty-one male subjects volunteered to participate in this study of the effects of an ultramarathon run under competitive conditions. Selected anthropometric measurements were made before and after the race. Blood samples were taken before, and within 10 min. of completing the race. Haematocrit and cortisol concentrations were analysed from each sample. Three ratings of perceived exertion (RPE) - local, central and overall, were obtained at two-hourly intervals throughout the race. The shortened form of the Eysenck Personality Inventory (EPI) was administered before the race. The Profile of Mood States (POMS) test was completed both before and immediately after the race. The average running intensity was estimated to be about 32% VO₂max which would not have caused major lactate accumulation. Repetitive compressive forces as a result of heel-strike resulted in intervertebral disc fluid loss. This resulted in a significant (p<0.05) decrease in stature after the race. Mobilization of glycogen, trig1ycerides and protein for metabolism as well as fluid loss via sweat resulted in significantly decreased body mass after the race. Plasma volume and serum cortisol concentrations were significantly increased after the race compared to pre-race baseline levels. Local RPE responses were dominant throughout the entire race, followed by overall RPE. Running 160 km had an effect on mood state. "Depression", "fatigue" and "confusion" (profile of Mood states) were all significantly increased compared to pre-race scores. Sleep deprivation as a result of running through the night was probably an important contributing factor. The anthropometric profile of the ultramarathon runners in this sample was more like that of the general population than elite marathon runners from the literature. The ultramarathon runners were more extroverted than elite marathon runners, but exhibited a similar Profile of Mood state before the race. The stressor - running 160 km - resulted in a 'strain response'. This was evident in the decreased stature and mass, and increased serum cortisol, "depression", "confusion" and above all "fatigue".
- Full Text:
- Date Issued: 1992
- Authors: Oltmann, Carmen
- Date: 1992
- Subjects: Marathon running -- Psychological effects , Marathon running -- Physiological effects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5148 , http://hdl.handle.net/10962/d1009706 , Marathon running -- Psychological effects , Marathon running -- Physiological effects
- Description: Twenty-one male subjects volunteered to participate in this study of the effects of an ultramarathon run under competitive conditions. Selected anthropometric measurements were made before and after the race. Blood samples were taken before, and within 10 min. of completing the race. Haematocrit and cortisol concentrations were analysed from each sample. Three ratings of perceived exertion (RPE) - local, central and overall, were obtained at two-hourly intervals throughout the race. The shortened form of the Eysenck Personality Inventory (EPI) was administered before the race. The Profile of Mood States (POMS) test was completed both before and immediately after the race. The average running intensity was estimated to be about 32% VO₂max which would not have caused major lactate accumulation. Repetitive compressive forces as a result of heel-strike resulted in intervertebral disc fluid loss. This resulted in a significant (p<0.05) decrease in stature after the race. Mobilization of glycogen, trig1ycerides and protein for metabolism as well as fluid loss via sweat resulted in significantly decreased body mass after the race. Plasma volume and serum cortisol concentrations were significantly increased after the race compared to pre-race baseline levels. Local RPE responses were dominant throughout the entire race, followed by overall RPE. Running 160 km had an effect on mood state. "Depression", "fatigue" and "confusion" (profile of Mood states) were all significantly increased compared to pre-race scores. Sleep deprivation as a result of running through the night was probably an important contributing factor. The anthropometric profile of the ultramarathon runners in this sample was more like that of the general population than elite marathon runners from the literature. The ultramarathon runners were more extroverted than elite marathon runners, but exhibited a similar Profile of Mood state before the race. The stressor - running 160 km - resulted in a 'strain response'. This was evident in the decreased stature and mass, and increased serum cortisol, "depression", "confusion" and above all "fatigue".
- Full Text:
- Date Issued: 1992
An evaluation of the use of computers in a South African primary school
- Authors: Mostert, Orla
- Date: 1992
- Subjects: Education, Elementary -- South Africa -- Computer-assisted instruction Computer-assisted instruction -- South Africa Educational technology -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1528 , http://hdl.handle.net/10962/d1003410
- Description: The introduction of the computer into the educational arena is unique as pressure for its inclusion has come not from educationalists, but from public demand based on the conviction that exposure to computers is an essential ingredient of modern education. This has resulted in computers being added to school curricula before there has been careful research into its educational implications, making huge demands on teachers involved in the innovation. South African primary schools involved in computer education have followed international trends in their adoption of computers, initially perceiving computer education as a separate subject added on to the present curriculum. However, changing trends in computer use internationally are now beginning to reflect educators' changing perceptions of the nature of primary education, and educators are calling for the use of computers to be integrated into the curriculum rather than being seen as an area of study in themselves. This investigation attempts to outline general trends and perceptions of computer use in a South African primary school. Despite a high level of computer usage at the observed school, the computer was seen by teachers, in the main, as an extra subject, and has not yet led to any significant changes in teaching styles and methods. The research suggests that two main issues need to be resolved before computer education in primary schools reflects the present paradigm shift towards learner-centered educational practices. Firstly, there is a need to rethink the delivery of the curriculum towards one which promotes a greater degree of problem solving and decision making on the part of the learner. Secondly, it would appear that teachers need to be made more aware of this trend.
- Full Text:
- Date Issued: 1992
- Authors: Mostert, Orla
- Date: 1992
- Subjects: Education, Elementary -- South Africa -- Computer-assisted instruction Computer-assisted instruction -- South Africa Educational technology -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1528 , http://hdl.handle.net/10962/d1003410
- Description: The introduction of the computer into the educational arena is unique as pressure for its inclusion has come not from educationalists, but from public demand based on the conviction that exposure to computers is an essential ingredient of modern education. This has resulted in computers being added to school curricula before there has been careful research into its educational implications, making huge demands on teachers involved in the innovation. South African primary schools involved in computer education have followed international trends in their adoption of computers, initially perceiving computer education as a separate subject added on to the present curriculum. However, changing trends in computer use internationally are now beginning to reflect educators' changing perceptions of the nature of primary education, and educators are calling for the use of computers to be integrated into the curriculum rather than being seen as an area of study in themselves. This investigation attempts to outline general trends and perceptions of computer use in a South African primary school. Despite a high level of computer usage at the observed school, the computer was seen by teachers, in the main, as an extra subject, and has not yet led to any significant changes in teaching styles and methods. The research suggests that two main issues need to be resolved before computer education in primary schools reflects the present paradigm shift towards learner-centered educational practices. Firstly, there is a need to rethink the delivery of the curriculum towards one which promotes a greater degree of problem solving and decision making on the part of the learner. Secondly, it would appear that teachers need to be made more aware of this trend.
- Full Text:
- Date Issued: 1992
Managing historical primary and secondary sources : a study of the efficacy of a teaching handbook prepared for first-year Vista University students
- Authors: Watson, Kelvin Innes
- Date: 1992
- Subjects: History -- Study and teaching (Secondary) -- South Africa History -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1670 , http://hdl.handle.net/10962/d1003553
- Description: This study examines the teaching of primary and secondary sources in history at secondary and tertiary level. The various methods used to teach these aspects of the nature of history are compared to the Vista University teaching model. To establish the effectiveness of the vista Block A module for HIS100 students, two test instruments were devised to assess their skills in handling primary and secondary sources. Their skills in identifying relevant points from a passage of historical prose were also tested. A number of statistical techniques were applied to the data from the test instruments. This data was analysed in qualitative and quantitative terms. The results of this analysis suggested that students would probably benefit from a skills-orientated approach to studying history. On the basis of this study, it is recommended that the existing Vista teaching model be revised or amended so that a more effective method of teaching students about the nature of historical sources can be introduced.
- Full Text:
- Date Issued: 1992
- Authors: Watson, Kelvin Innes
- Date: 1992
- Subjects: History -- Study and teaching (Secondary) -- South Africa History -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1670 , http://hdl.handle.net/10962/d1003553
- Description: This study examines the teaching of primary and secondary sources in history at secondary and tertiary level. The various methods used to teach these aspects of the nature of history are compared to the Vista University teaching model. To establish the effectiveness of the vista Block A module for HIS100 students, two test instruments were devised to assess their skills in handling primary and secondary sources. Their skills in identifying relevant points from a passage of historical prose were also tested. A number of statistical techniques were applied to the data from the test instruments. This data was analysed in qualitative and quantitative terms. The results of this analysis suggested that students would probably benefit from a skills-orientated approach to studying history. On the basis of this study, it is recommended that the existing Vista teaching model be revised or amended so that a more effective method of teaching students about the nature of historical sources can be introduced.
- Full Text:
- Date Issued: 1992
The anatomy and ecophysiology of Mariscus congestus from three different habitats in the Albany and Bathurst districts of the Eastern Cape, investigated under field and laboratory conditions
- Authors: Sonnenberg, Bernd Jürgen
- Date: 1992
- Subjects: Cyperaceae -- South Africa , Plant anatomy , Plant physiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4229 , http://hdl.handle.net/10962/d1003798 , Cyperaceae -- South Africa , Plant anatomy , Plant physiology
- Description: An investigation of the anatomy and gas exchange characteristics of Mariscus congestus in three different habitats was undertaken in order to establish whether M. congestus from the three different habitats displayed any ecotypic responses when placed in a new similar environment. It was hoped that the results of this investigation would yield evidence that would support the ecotype concept similar to the investigations of Milner and Hiesey (1964), Green (1969) and Slayter and Ferrar (1977). On the basis of the site leaf anatomy, M. congestus investigated at the coast (site 1) differed in many respects from the inland plants (sites 2 and 3). These differences suggest that the coastal plants may have undergone a slight ecotypic divergence from the inland plants. The anatomical investigation also suggested that the leaves of M. congestus from all three sites may either be C₄ NADP-ME or PCK and that all had typical Chlorocyperiod anatomy. The habitat microclimates at sites 1-3 had different light and water regimes. There were no significant differences between the 12 month temperature environments of the three sites. There was however, a minor difference between the coastal (high temperature) and the inland (lower temperature) sites. M. congestus at the three sites had significantly different CO₂ assimilation rates, transpiration and stomatal conductance in response to the differing habitat microclimates. The water use efficiency of the sites were however, similar. Site 1 attained the highest CO₂ assimilation rates, transpiration, stomatal conductance, and water use efficiency and site 3 the lowest. Under similar conditions the gas exchange data for the potted plants indicated that M. congestus from the different sites was typically C₄. The optimal photosynthetic temperatures of all the sites was above 30°C and they did not show significant inhibition of CO₂ assimilation by different oxygen concentrations. The results of the laboratory investigation of the potted plants suggested that the only site-specific (ecotypic) response of M. eongestus was the light intensity at which the plants from the different sites were light saturated. The light and temperature response of field plants under field conditions was not comparable to the light and temperature response of potted plants under laboratory conditions. This may have been due to the field results being obtained under differing water and soil nutrient regimes. The potted plants may also have had a reduced root mass compared to their field counterparts and the potted plants may have also have become root bound. Under field conditions the plants had differing light saturation points and optimal photosynthetic temperatures compared to the potted plants. This investigation thus did not support the hypothesis stated in this thesis. The data in this investigation thus may indicate that plants with as diverse habitats as Mariscus congestus that are removed from their natural habitats display rapid changes in gas exchange characteristics in response to their new microclimates, with few ecotypic physiological characteristics of the old habitat being retained.
- Full Text:
- Date Issued: 1992
- Authors: Sonnenberg, Bernd Jürgen
- Date: 1992
- Subjects: Cyperaceae -- South Africa , Plant anatomy , Plant physiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4229 , http://hdl.handle.net/10962/d1003798 , Cyperaceae -- South Africa , Plant anatomy , Plant physiology
- Description: An investigation of the anatomy and gas exchange characteristics of Mariscus congestus in three different habitats was undertaken in order to establish whether M. congestus from the three different habitats displayed any ecotypic responses when placed in a new similar environment. It was hoped that the results of this investigation would yield evidence that would support the ecotype concept similar to the investigations of Milner and Hiesey (1964), Green (1969) and Slayter and Ferrar (1977). On the basis of the site leaf anatomy, M. congestus investigated at the coast (site 1) differed in many respects from the inland plants (sites 2 and 3). These differences suggest that the coastal plants may have undergone a slight ecotypic divergence from the inland plants. The anatomical investigation also suggested that the leaves of M. congestus from all three sites may either be C₄ NADP-ME or PCK and that all had typical Chlorocyperiod anatomy. The habitat microclimates at sites 1-3 had different light and water regimes. There were no significant differences between the 12 month temperature environments of the three sites. There was however, a minor difference between the coastal (high temperature) and the inland (lower temperature) sites. M. congestus at the three sites had significantly different CO₂ assimilation rates, transpiration and stomatal conductance in response to the differing habitat microclimates. The water use efficiency of the sites were however, similar. Site 1 attained the highest CO₂ assimilation rates, transpiration, stomatal conductance, and water use efficiency and site 3 the lowest. Under similar conditions the gas exchange data for the potted plants indicated that M. congestus from the different sites was typically C₄. The optimal photosynthetic temperatures of all the sites was above 30°C and they did not show significant inhibition of CO₂ assimilation by different oxygen concentrations. The results of the laboratory investigation of the potted plants suggested that the only site-specific (ecotypic) response of M. eongestus was the light intensity at which the plants from the different sites were light saturated. The light and temperature response of field plants under field conditions was not comparable to the light and temperature response of potted plants under laboratory conditions. This may have been due to the field results being obtained under differing water and soil nutrient regimes. The potted plants may also have had a reduced root mass compared to their field counterparts and the potted plants may have also have become root bound. Under field conditions the plants had differing light saturation points and optimal photosynthetic temperatures compared to the potted plants. This investigation thus did not support the hypothesis stated in this thesis. The data in this investigation thus may indicate that plants with as diverse habitats as Mariscus congestus that are removed from their natural habitats display rapid changes in gas exchange characteristics in response to their new microclimates, with few ecotypic physiological characteristics of the old habitat being retained.
- Full Text:
- Date Issued: 1992
An assessment of a new personality measure of authoritarianism in the South African context
- Authors: Léger, Paul
- Date: 1992
- Subjects: Authoritarianism (Personality trait) -- Research , Authoritarianism -- Research -- South Africa , Psychological tests -- Research , Personality tests -- Research
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3007 , http://hdl.handle.net/10962/d1002516 , Authoritarianism (Personality trait) -- Research , Authoritarianism -- Research -- South Africa , Psychological tests -- Research , Personality tests -- Research
- Description: The aim of the research was to assess the psychometric properties of Altemeyer's (1981) Right-Wing Authoritarianism scale (RWA scale)- developed in response to identified methodological weaknesses in personality measures of authoritarianism to date - within a South African setting. A modified version of the 24-item attitudinal scale, together with a demographic questionnaire was administered to a white and black sample of South African university students. Subsequent psychometric analysis of the data indicated that the scale was a significantly less powerful measure of authoritarianism in a cross-cultural context, than originally hoped for. Not only did the analysis show an absence of psychometric equivalence but revealed substantial problems within the content of the scale itself. An ensuing discussion of these findings situated the debate within a broader theoretical context. It was argued that the RWA scale, and its underpinning conceptualization, although possibly comprising a methodological refinement over existing measures of authoritarianism, did not constitute grounds for a viable approach to research on authoritarianism in the South African context. It was concluded that a model of authoritarianism resting on the assumptions of positivistic psychology, inevitably failed to account for the social and political dynamics of a changing society. As a socially relevant enterprise, it was suggested that the debate on authoritarianism be extended beyond the confines of individualistic psychology and research priority directed instead to the crucial role of societal factors giving rise to the individual manifestation of the phenomenon.
- Full Text:
- Date Issued: 1992
- Authors: Léger, Paul
- Date: 1992
- Subjects: Authoritarianism (Personality trait) -- Research , Authoritarianism -- Research -- South Africa , Psychological tests -- Research , Personality tests -- Research
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3007 , http://hdl.handle.net/10962/d1002516 , Authoritarianism (Personality trait) -- Research , Authoritarianism -- Research -- South Africa , Psychological tests -- Research , Personality tests -- Research
- Description: The aim of the research was to assess the psychometric properties of Altemeyer's (1981) Right-Wing Authoritarianism scale (RWA scale)- developed in response to identified methodological weaknesses in personality measures of authoritarianism to date - within a South African setting. A modified version of the 24-item attitudinal scale, together with a demographic questionnaire was administered to a white and black sample of South African university students. Subsequent psychometric analysis of the data indicated that the scale was a significantly less powerful measure of authoritarianism in a cross-cultural context, than originally hoped for. Not only did the analysis show an absence of psychometric equivalence but revealed substantial problems within the content of the scale itself. An ensuing discussion of these findings situated the debate within a broader theoretical context. It was argued that the RWA scale, and its underpinning conceptualization, although possibly comprising a methodological refinement over existing measures of authoritarianism, did not constitute grounds for a viable approach to research on authoritarianism in the South African context. It was concluded that a model of authoritarianism resting on the assumptions of positivistic psychology, inevitably failed to account for the social and political dynamics of a changing society. As a socially relevant enterprise, it was suggested that the debate on authoritarianism be extended beyond the confines of individualistic psychology and research priority directed instead to the crucial role of societal factors giving rise to the individual manifestation of the phenomenon.
- Full Text:
- Date Issued: 1992
A study of the effect of progesterone on the body weight regulation in intact female rats
- Authors: Ravelingien, Jo
- Date: 1992
- Subjects: Progesterone -- Physiological effect , Body weight -- Regulation , Rats -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3787 , http://hdl.handle.net/10962/d1003265 , Progesterone -- Physiological effect , Body weight -- Regulation , Rats -- Research
- Description: It is the aim of this study to elucidate the influence of progesterone on body weight regulation in intact female rats. A study of the literature includes a description of the body weight regulation and the effects of ovarian hormones on it. The controlled-system approach tries to link behavioral and physiological factors altering energy balance. The experimental study is subdivided into food-intake - and food-selection studies, a locomotor activity study, a study eliciting a possible role of thermogenesis, and finally rat liver studies which consist of a gas chromatography analysis of hepatic fatty acids and an electron microscopy study examining the ultrastructure of hepatocytes. It can be concluded that the effect of progesterone treatment on the body weight of intact female rats depends on the route of administration. There is a significant increase in body weight after subcutaneous progesterone injections without changes in total caloric intake and nutrient selection habits, indicating the importance of energy expenditure. But changes in spontaneous activity make no contribution in the progesterone-induced energy storage. It is also concluded that peripherally located brown adipose tissue thermogenesis is not changed, without ruling out the effect of more centrally located thermogenic organs as the liver. In this organ, small but significant changes in the fatty acid profile occur during the subcutaneous progesterone treatment.
- Full Text:
- Date Issued: 1992
- Authors: Ravelingien, Jo
- Date: 1992
- Subjects: Progesterone -- Physiological effect , Body weight -- Regulation , Rats -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3787 , http://hdl.handle.net/10962/d1003265 , Progesterone -- Physiological effect , Body weight -- Regulation , Rats -- Research
- Description: It is the aim of this study to elucidate the influence of progesterone on body weight regulation in intact female rats. A study of the literature includes a description of the body weight regulation and the effects of ovarian hormones on it. The controlled-system approach tries to link behavioral and physiological factors altering energy balance. The experimental study is subdivided into food-intake - and food-selection studies, a locomotor activity study, a study eliciting a possible role of thermogenesis, and finally rat liver studies which consist of a gas chromatography analysis of hepatic fatty acids and an electron microscopy study examining the ultrastructure of hepatocytes. It can be concluded that the effect of progesterone treatment on the body weight of intact female rats depends on the route of administration. There is a significant increase in body weight after subcutaneous progesterone injections without changes in total caloric intake and nutrient selection habits, indicating the importance of energy expenditure. But changes in spontaneous activity make no contribution in the progesterone-induced energy storage. It is also concluded that peripherally located brown adipose tissue thermogenesis is not changed, without ruling out the effect of more centrally located thermogenic organs as the liver. In this organ, small but significant changes in the fatty acid profile occur during the subcutaneous progesterone treatment.
- Full Text:
- Date Issued: 1992
Opaqueness to the light of understanding: an investigation into some of the difficulties experienced by a sample of Transkeian matriculants with the components of the concept of chemical equilibrium
- Authors: Mammen, Kuttickattu John
- Date: 1992
- Subjects: Chemical equilibrium Physical sciences -- Study and teaching (Secondary) -- South Africa -- Transkei Black people -- Education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1680 , http://hdl.handle.net/10962/d1003563
- Description: The purpose of the study was to collect and collate information pertaining to common misconceptions of components of the concept of chemical equilibrium amongst a sample of Transkeian matriculants. 'Equilibrium' is a fundamental concept in physics and chemistry and 'chemical equilibrium' is an important chemistry topic in both the higher grade and standard grade South African matriculation physical science syllabuses. In recent years, South African teachers have identified chemical equilibrium as the most difficult section of the matric physical science syllabus for both teachers and pupils. It has been shown that teachers themselves lack understanding of the basic concepts underlying chemical equilibrium. Constructivist learning theories arise out of research in cognitive psychology. These theories conceive of cognitive development as the assimilation and accommodation of new ideas into extant, dynamic cognitive structures. An inference from the theories is that a study of the preconceptions and/or misconceptions held by pupils before they are exposed to instruction would enable teachers to avoid generating or reinforcing misconceptions. Hence teachers could also take deliberate steps to eradicate those already existing. The sample consisted of 112 Transkeian matriculants from four government senior secondary schools in the Southern Transkei. All were taking physical science. The test consisted of a 40 item multiple choice battery. Each question had three distracters and the options were randomized to avoid patterns and hence guessing. Questions dealing with closely associated concepts were grouped in the paper but no indication of this was given in the paper. The questions are analyzed singly. A brief introduction and outline of the theory on which the group of questions was based is given in each case. The analysis makes use of the frequency of choice of all options, discrimination indices, although they were generally low and item difficulties. The intent in each analysis is to identify the possible misconception(s) underlying wrong answers. Finally conclusions based on the discussion are drawn and recommendations for teaching and further research made.
- Full Text:
- Date Issued: 1992
- Authors: Mammen, Kuttickattu John
- Date: 1992
- Subjects: Chemical equilibrium Physical sciences -- Study and teaching (Secondary) -- South Africa -- Transkei Black people -- Education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1680 , http://hdl.handle.net/10962/d1003563
- Description: The purpose of the study was to collect and collate information pertaining to common misconceptions of components of the concept of chemical equilibrium amongst a sample of Transkeian matriculants. 'Equilibrium' is a fundamental concept in physics and chemistry and 'chemical equilibrium' is an important chemistry topic in both the higher grade and standard grade South African matriculation physical science syllabuses. In recent years, South African teachers have identified chemical equilibrium as the most difficult section of the matric physical science syllabus for both teachers and pupils. It has been shown that teachers themselves lack understanding of the basic concepts underlying chemical equilibrium. Constructivist learning theories arise out of research in cognitive psychology. These theories conceive of cognitive development as the assimilation and accommodation of new ideas into extant, dynamic cognitive structures. An inference from the theories is that a study of the preconceptions and/or misconceptions held by pupils before they are exposed to instruction would enable teachers to avoid generating or reinforcing misconceptions. Hence teachers could also take deliberate steps to eradicate those already existing. The sample consisted of 112 Transkeian matriculants from four government senior secondary schools in the Southern Transkei. All were taking physical science. The test consisted of a 40 item multiple choice battery. Each question had three distracters and the options were randomized to avoid patterns and hence guessing. Questions dealing with closely associated concepts were grouped in the paper but no indication of this was given in the paper. The questions are analyzed singly. A brief introduction and outline of the theory on which the group of questions was based is given in each case. The analysis makes use of the frequency of choice of all options, discrimination indices, although they were generally low and item difficulties. The intent in each analysis is to identify the possible misconception(s) underlying wrong answers. Finally conclusions based on the discussion are drawn and recommendations for teaching and further research made.
- Full Text:
- Date Issued: 1992