From imifino to umfuno : a case study foregrounding indigenous agricultural knowledge in school-based curriculum development
- Authors: Asafo-Adjei, Robert Tetteh
- Date: 2004
- Subjects: Plants, Edible -- South Africa -- Eastern Cape Wild plants, Edible -- South Africa -- Eastern Cape Human-plant relationships -- South Africa -- Eastern Cape Endemic plants -- South Africa Agricultural education Agriculture -- Study and teaching -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1829 , http://hdl.handle.net/10962/d1003731
- Description: This work is a school-based case study conducted amongst learners of a rural High School and the immediate community in Whittlesea in the Eastern Cape where I teach. The research was conducted by using different research methods such as worksheets, questionnaires, interviews, practical activities and observations as well as photographs to investigate three indigenous wild local vegetable food plants (imifino). The fundamental assumption of the research is that, imifino can be looked after and cared for, to become valuable vegetable food plants which can be used as supplements to the cultivated vegetable food plants (umfuno). The question was: How could this concept be brought into the curriculum? It had also been assumed that bringing knowledge of imifino into curriculwn contexts could be of benefit to South African learners. The study produced a variety of findings: • There is a general feeling that those who eat imifino are the poor. • There is a lack of interest among women interviewed in the preparation process, for example going to pick the food plants from the fields, washing them and preparing the leaves as food. • AmaXhosa males look upon eating imifino with contempt. • Some males among the younger generation are beginning to overlook tradition and are eating imifino. • Inclusion of indigenous agricultural knowledge in the curriculum was supported by learners and community members. Learners have interest in knowing about indigenous food plants. • Learners feel as Africans that they must learn about the indigenous food plants in school in order not to lose knowledge of these plants completely. • The study also identified that interpretation of learning outcomes with an indigenous knowledge focus, requires careful attention to socio-cultural factors, and not just technical/ practical factors. Previous knowledge of learners and community members about imifino was mobilized to develop a sample OBE learning programme unit (LPU /Lesson plan) for the Grade 10 FET of Agricultural Science curriculum. The case study illustrates that Learning outcome 3 of the Agricultural Science subject can be achieved if educators involve learners and community members in developing learning programmes.
- Full Text:
- Date Issued: 2004
- Authors: Asafo-Adjei, Robert Tetteh
- Date: 2004
- Subjects: Plants, Edible -- South Africa -- Eastern Cape Wild plants, Edible -- South Africa -- Eastern Cape Human-plant relationships -- South Africa -- Eastern Cape Endemic plants -- South Africa Agricultural education Agriculture -- Study and teaching -- South Africa -- Eastern Cape Xhosa (African people) -- Social life and customs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1829 , http://hdl.handle.net/10962/d1003731
- Description: This work is a school-based case study conducted amongst learners of a rural High School and the immediate community in Whittlesea in the Eastern Cape where I teach. The research was conducted by using different research methods such as worksheets, questionnaires, interviews, practical activities and observations as well as photographs to investigate three indigenous wild local vegetable food plants (imifino). The fundamental assumption of the research is that, imifino can be looked after and cared for, to become valuable vegetable food plants which can be used as supplements to the cultivated vegetable food plants (umfuno). The question was: How could this concept be brought into the curriculum? It had also been assumed that bringing knowledge of imifino into curriculwn contexts could be of benefit to South African learners. The study produced a variety of findings: • There is a general feeling that those who eat imifino are the poor. • There is a lack of interest among women interviewed in the preparation process, for example going to pick the food plants from the fields, washing them and preparing the leaves as food. • AmaXhosa males look upon eating imifino with contempt. • Some males among the younger generation are beginning to overlook tradition and are eating imifino. • Inclusion of indigenous agricultural knowledge in the curriculum was supported by learners and community members. Learners have interest in knowing about indigenous food plants. • Learners feel as Africans that they must learn about the indigenous food plants in school in order not to lose knowledge of these plants completely. • The study also identified that interpretation of learning outcomes with an indigenous knowledge focus, requires careful attention to socio-cultural factors, and not just technical/ practical factors. Previous knowledge of learners and community members about imifino was mobilized to develop a sample OBE learning programme unit (LPU /Lesson plan) for the Grade 10 FET of Agricultural Science curriculum. The case study illustrates that Learning outcome 3 of the Agricultural Science subject can be achieved if educators involve learners and community members in developing learning programmes.
- Full Text:
- Date Issued: 2004
Genetic analysis of the Octopus vulgaris population on the coast of South Africa
- Oosthuizen, Ané, Jiwaji, Meesbah, Shaw, Paul W
- Authors: Oosthuizen, Ané , Jiwaji, Meesbah , Shaw, Paul W
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6761 , http://hdl.handle.net/10962/d1007922
- Description: This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distance based methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.
- Full Text:
- Date Issued: 2004
- Authors: Oosthuizen, Ané , Jiwaji, Meesbah , Shaw, Paul W
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6761 , http://hdl.handle.net/10962/d1007922
- Description: This study on Octopus vulgaris focused on the COIII gene region of mitochondrial DNA. Sequences from 21 samples from the Eastern Cape, and 14 samples from the Western Cape, were compared to determine whether different populations exist along the South African coast. A 380-bp segment of the COIII region of mtDNA was amplified using the polymerase chain reaction with specific designed primers. Phylogenetic inference was made using maximum parsimony (MP), maximum likelihood (ML), and distance based methods. All sequences conformed to a single haplotype. Lack of variation within and between east and west coast samples precluded further population genetic analysis. The sequence obtained in this study was also compared with other sequences lodged in the Genbank database. Phylogenetically, the South African O. vulgaris is closely related to O. vulgaris from Senegal (0.67% divergence) and the Mediterranean (1.51% divergence). Within the Mediterranean group, O. vulgaris from South Africa displayed less sequence divergence from Senegalese and Mediterranean individuals than O. vulgaris from Venezuela (3.85%) and Taiwan (3.87%). These data do not, therefore, refute the hypothesis of a single O. vulgaris genetic population around the coast.
- Full Text:
- Date Issued: 2004
Geographic susceptibility of Helicoverpa armigera (Lepidoptera: Noctuidae) to insecticidal proteins in Bt-cotton in South Africa
- Van Jaarsveld, Martha Johanna
- Authors: Van Jaarsveld, Martha Johanna
- Date: 2004
- Subjects: Helicoverpa armigera , Noctuidae , Lepidoptera , Cotton -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5701 , http://hdl.handle.net/10962/d1005387 , Helicoverpa armigera , Noctuidae , Lepidoptera , Cotton -- Diseases and pests -- South Africa
- Description: Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) (African bollworm) is a typical noctuid with a very catholic taste in food plants and whose larvae feed on a wide range of cultivated and wild plants. It has been identified as the most polyphagous and injurious pest in South Africa. Helicoverpa armigera is also a key pest of cotton in many parts of the world. This key pest requires extensive control as it adversely effects yield and has built up resistance to synthetic pyrethroid insecticides. Cotton is an important crop produced by commercial and small-scale farmers in South Africa. The local demand for cotton has not been exceeded yet, but to satisfy a demanding market, pest control costs play an important role in cotton production. The threat of an insect pest that has already shown resistance prompted the present study to investigate the possibility of resistance to Bt-cotton. Genetically engineered or Bt-cotton was introduced commercially in 1996 in South Africa. All Bt-cotton plants contain one or more foreign genes derived from the soil-dwelling bacterium, Bacillus thuringiensis (Berliner), which produces protein crystals. These crystals were isolated and transferred into the genome of a cotton plant resulting in the plant producing it’s own protein insecticide. In 1998, Monsanto (Pty) Ltd requested research into the geographic susceptibility of H. armigera to the insecticidal proteins in Bt-cotton in SA. Laboratory reared and field sampled populations of H. armigera were exposed to a diet mixed with various baseline concentrations of the Bt-gene Cry1Ac freeze dried protein. This study also determined the performance of H. armigera and Spodoptera littoralis (Boisduval) on different Bt-cotton field cultivars containing different Cry-protein genes. Results obtained indicated a significant difference in susceptibility in two field populations of H. armigera to the Bt-protein Cry1Ac, even though the LD50,s in the 2003 season did not indicate resistance. Bt-cotton cultivar 15985 BX controlled H. armigera and S. littoralis larvae, the best followed in descending order by cultivar 15985 X, 15985 B and DP50 B. Results on H. armigera also indicated that the Cry-proteins in the plant parts of the different cultivars did not diminish as the season progressed. The Bt-cotton cultivars induced retarded growth of larvae, due to either a repellent effect or lack of feeding by larvae. Widespread adoption of Bt-cotton by South African farmers led to regional declines in bollworm populations, reduced insecticide use, and increased yields. Genetically modified crops therefore contribute to a cost effective, sustainable, productive and efficient form of agriculture, with a resultant positive impact on the environment. As the market for commercial Bt-cotton in South Africa expands, it is recommended that a monitoring programme for potential resistant genes in H. armigera should be implemented at least every 2 - 3 years. This will ensure that effective resistance management strategies are utilised. Coupled with this are the Biosafety Risks regarding the effect of new proteins expressed in transgenic plants, which require further studies.
- Full Text:
- Date Issued: 2004
- Authors: Van Jaarsveld, Martha Johanna
- Date: 2004
- Subjects: Helicoverpa armigera , Noctuidae , Lepidoptera , Cotton -- Diseases and pests -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5701 , http://hdl.handle.net/10962/d1005387 , Helicoverpa armigera , Noctuidae , Lepidoptera , Cotton -- Diseases and pests -- South Africa
- Description: Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) (African bollworm) is a typical noctuid with a very catholic taste in food plants and whose larvae feed on a wide range of cultivated and wild plants. It has been identified as the most polyphagous and injurious pest in South Africa. Helicoverpa armigera is also a key pest of cotton in many parts of the world. This key pest requires extensive control as it adversely effects yield and has built up resistance to synthetic pyrethroid insecticides. Cotton is an important crop produced by commercial and small-scale farmers in South Africa. The local demand for cotton has not been exceeded yet, but to satisfy a demanding market, pest control costs play an important role in cotton production. The threat of an insect pest that has already shown resistance prompted the present study to investigate the possibility of resistance to Bt-cotton. Genetically engineered or Bt-cotton was introduced commercially in 1996 in South Africa. All Bt-cotton plants contain one or more foreign genes derived from the soil-dwelling bacterium, Bacillus thuringiensis (Berliner), which produces protein crystals. These crystals were isolated and transferred into the genome of a cotton plant resulting in the plant producing it’s own protein insecticide. In 1998, Monsanto (Pty) Ltd requested research into the geographic susceptibility of H. armigera to the insecticidal proteins in Bt-cotton in SA. Laboratory reared and field sampled populations of H. armigera were exposed to a diet mixed with various baseline concentrations of the Bt-gene Cry1Ac freeze dried protein. This study also determined the performance of H. armigera and Spodoptera littoralis (Boisduval) on different Bt-cotton field cultivars containing different Cry-protein genes. Results obtained indicated a significant difference in susceptibility in two field populations of H. armigera to the Bt-protein Cry1Ac, even though the LD50,s in the 2003 season did not indicate resistance. Bt-cotton cultivar 15985 BX controlled H. armigera and S. littoralis larvae, the best followed in descending order by cultivar 15985 X, 15985 B and DP50 B. Results on H. armigera also indicated that the Cry-proteins in the plant parts of the different cultivars did not diminish as the season progressed. The Bt-cotton cultivars induced retarded growth of larvae, due to either a repellent effect or lack of feeding by larvae. Widespread adoption of Bt-cotton by South African farmers led to regional declines in bollworm populations, reduced insecticide use, and increased yields. Genetically modified crops therefore contribute to a cost effective, sustainable, productive and efficient form of agriculture, with a resultant positive impact on the environment. As the market for commercial Bt-cotton in South Africa expands, it is recommended that a monitoring programme for potential resistant genes in H. armigera should be implemented at least every 2 - 3 years. This will ensure that effective resistance management strategies are utilised. Coupled with this are the Biosafety Risks regarding the effect of new proteins expressed in transgenic plants, which require further studies.
- Full Text:
- Date Issued: 2004
Globalisation as a business strategy for South African architectural practices
- Authors: Vosloo, Christo
- Date: 2004
- Subjects: Globalization , Architectural firms -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9271 , http://hdl.handle.net/10948/234 , Globalization , Architectural firms -- South Africa
- Description: Globalisation has become a common topic of discussion and research. This treatise focuses on its role as part of the business of Architectural practice. It investigates the reasons why selected South African Architectural practices decided to globalise, how this decision was reached, implemented and how successful the decisions were. Based on the findings of a literature study it uses the case study methodology to confirm the findings that the strategic position of South African Architectural practices is one where practical and historical reasons exist for the profession to embark on a globalisation strategy. The studies confirm that a globalisation strategy presents a suitable, feasible and acceptable strategy for South African Architectural practices. However, a disconcerting element of the findings was the fact that there are strong indications that South African Architectural practices do not realise the potential benefits inherent in regular strategic planning. Thus it recommends that such a strategy should be based on specialist knowledge or experience, that opening an office in the area to which firms wish to expand will greatly enhance the chances of success, that formal strategic planning processes should be used to ensure that such a strategy is an appropriate one and to identify the countries to which the firm plans to expand its services. Furthermore, it recommends that Government should recognise that firms expanding in this manner hold specific advantages for the national economy and introduce steps to support the profession so that it may build the capacity and skills required therefore. In addition it recommends that the relevant professional bodies should ensure that their members have the business and managerial skills required to ensure the achievement of these objectives.
- Full Text:
- Date Issued: 2004
- Authors: Vosloo, Christo
- Date: 2004
- Subjects: Globalization , Architectural firms -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9271 , http://hdl.handle.net/10948/234 , Globalization , Architectural firms -- South Africa
- Description: Globalisation has become a common topic of discussion and research. This treatise focuses on its role as part of the business of Architectural practice. It investigates the reasons why selected South African Architectural practices decided to globalise, how this decision was reached, implemented and how successful the decisions were. Based on the findings of a literature study it uses the case study methodology to confirm the findings that the strategic position of South African Architectural practices is one where practical and historical reasons exist for the profession to embark on a globalisation strategy. The studies confirm that a globalisation strategy presents a suitable, feasible and acceptable strategy for South African Architectural practices. However, a disconcerting element of the findings was the fact that there are strong indications that South African Architectural practices do not realise the potential benefits inherent in regular strategic planning. Thus it recommends that such a strategy should be based on specialist knowledge or experience, that opening an office in the area to which firms wish to expand will greatly enhance the chances of success, that formal strategic planning processes should be used to ensure that such a strategy is an appropriate one and to identify the countries to which the firm plans to expand its services. Furthermore, it recommends that Government should recognise that firms expanding in this manner hold specific advantages for the national economy and introduce steps to support the profession so that it may build the capacity and skills required therefore. In addition it recommends that the relevant professional bodies should ensure that their members have the business and managerial skills required to ensure the achievement of these objectives.
- Full Text:
- Date Issued: 2004
Gold exploration northeast of Ngundu Halt, northern marginal zone of the Limpopo Belt, Zimbabwe
- Authors: Simango, Robert Zulu
- Date: 2004 , 2013-05-30
- Subjects: Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5007 , http://hdl.handle.net/10962/d1005844 , Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Description: Gold exploration was conducted in northern margin, granulite-facies rocks of the Limpopo Belt. Methods used in the prospecting include drainage, soil and rock geochemistry, geophysical surveys, geological mapping, trenching and diamond drilling. These techniques successfully led to the discovery of two medium size, mesothermal gold deposits (Grid 2s and Grid 4). Objectives of this study were to (a) document the exploration methodology used; (b) describe the regional geology; (c) establish a mineral deposit model; (d) outline the methods and results of various exploration techniques; (e) outline follow-up procedures and evaluation of anomalies; and (f) discuss results of the exploration exercise and conclusions. The granulite-facies terrain comprises Charno-enderbites, mafic and felsic to intermediate metavolcanic rocks and meta-sediments. Renco Mine situated immediately east of the study area, was selected as the ore deposit model for the exploration program. Gold mineralization occurs in shear and thrust zones within an enderbite. The gold deposits are structurally controlled by a first-order, Sinistral transcrustal Mauch Shear Zone, which is parallel to a regional east-northeast penetrative foliation. The deposits are in dilation zones where the Mauch Shear (a) is intersected by a dextral east-west shear (Grid 2s), or (b) has a sinistral splay (Grid 4 and Renco). Close to these deposits, the Mauch Shear is in contact with a "greenstone belt", which is a possible source of crustal metamorphic ore fluids and gold. The Grid 2s deposit contains fine-grained, disseminated free gold, and small amounts of pyrrhotite, pyrite and chalcopyrite in quartz veins within third-order shears in K-feldspar granite. K-feldspar, sericitic, silicic, sulphidation and carbonate alteration characterizes the deposit, which has a proposed mantle-degassing model. The Grid 4 deposit is magmatic porphyry-type, with CuMo and Au in third- and fourth-order shears respectively. Mineralization comprises disseminated to semi-massive pyrrhotite, pyrite, chalcopyrite, sphalerite, bismuth, molybdenite and gold. Wall rock alteration includes biotitic, chloritic, silicic, sulphidation and carbonate. In Grid 2s, Grid 4 and Renco deposits, the alteration mineral assemblages are in three facies, which are granulite, amphibolte and greenschist. In the three deposits, the mineralization occurs with the amphibolite-facies, indicating post-peak, retrograde metamorphic conditions. , Illustrations (maps) only available in print form at Cory Library , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
- Authors: Simango, Robert Zulu
- Date: 2004 , 2013-05-30
- Subjects: Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5007 , http://hdl.handle.net/10962/d1005844 , Geology -- Zimbabwe , Gold ores -- Geology -- Zimbabwe , Greenstone belts -- Zimbabwe , Gold mines and mining -- Zimbabwe
- Description: Gold exploration was conducted in northern margin, granulite-facies rocks of the Limpopo Belt. Methods used in the prospecting include drainage, soil and rock geochemistry, geophysical surveys, geological mapping, trenching and diamond drilling. These techniques successfully led to the discovery of two medium size, mesothermal gold deposits (Grid 2s and Grid 4). Objectives of this study were to (a) document the exploration methodology used; (b) describe the regional geology; (c) establish a mineral deposit model; (d) outline the methods and results of various exploration techniques; (e) outline follow-up procedures and evaluation of anomalies; and (f) discuss results of the exploration exercise and conclusions. The granulite-facies terrain comprises Charno-enderbites, mafic and felsic to intermediate metavolcanic rocks and meta-sediments. Renco Mine situated immediately east of the study area, was selected as the ore deposit model for the exploration program. Gold mineralization occurs in shear and thrust zones within an enderbite. The gold deposits are structurally controlled by a first-order, Sinistral transcrustal Mauch Shear Zone, which is parallel to a regional east-northeast penetrative foliation. The deposits are in dilation zones where the Mauch Shear (a) is intersected by a dextral east-west shear (Grid 2s), or (b) has a sinistral splay (Grid 4 and Renco). Close to these deposits, the Mauch Shear is in contact with a "greenstone belt", which is a possible source of crustal metamorphic ore fluids and gold. The Grid 2s deposit contains fine-grained, disseminated free gold, and small amounts of pyrrhotite, pyrite and chalcopyrite in quartz veins within third-order shears in K-feldspar granite. K-feldspar, sericitic, silicic, sulphidation and carbonate alteration characterizes the deposit, which has a proposed mantle-degassing model. The Grid 4 deposit is magmatic porphyry-type, with CuMo and Au in third- and fourth-order shears respectively. Mineralization comprises disseminated to semi-massive pyrrhotite, pyrite, chalcopyrite, sphalerite, bismuth, molybdenite and gold. Wall rock alteration includes biotitic, chloritic, silicic, sulphidation and carbonate. In Grid 2s, Grid 4 and Renco deposits, the alteration mineral assemblages are in three facies, which are granulite, amphibolte and greenschist. In the three deposits, the mineralization occurs with the amphibolite-facies, indicating post-peak, retrograde metamorphic conditions. , Illustrations (maps) only available in print form at Cory Library , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2004
Harvesting impacts on commonly used medicinal tree species (Catha edulis and Rapanea melanophloeos) under different land management regimes in the Mpumalanga Lowveld, South Africa
- Botha, Jenny, Witkowski, Ed T F, Shackleton, Charlie M
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181379 , vital:43728 , xlink:href="https://doi.org/10.4102/koedoe.v47i2.77"
- Description: Harvesting of products from plants in the wild is widespread throughout southern Africa. Particularly important products are plant parts used in traditional medicine. However, the impacts of harvesting practices are rarely quantified, with as yet insufficient generic rules across species and life forms. This limits the predictive ability to monitor and manage the affected populations. This paper examines the harvesting impact on two popular woody medicinal species used throughout sub-Saharan Africa, namely Catha edulis (Vahl) Forssk. ex Endl. (bushman’s tea) and Rapanea melanophloeos (L.) Mez. (Cape beech). In both species, basal diameters, heights, and the number of size classes in the harvested populations were lower than in unharvested. Densities of harvested populations were higher in both species, including densities of young plants, but the frequency of individuals in larger size classes was lower. The populations of both species being harvested for medicinal products appeared to be withstanding the current levels of harvesting, but the population structure of C. edulis populations being harvested for poles on the roadside and near human settlements had been substantially altered. Despite the resilience of the two species to harvesting for medicinal products, loss of habitat or changes in land use pose a threat to a number of the assessed populations.
- Full Text:
- Date Issued: 2004
- Authors: Botha, Jenny , Witkowski, Ed T F , Shackleton, Charlie M
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181379 , vital:43728 , xlink:href="https://doi.org/10.4102/koedoe.v47i2.77"
- Description: Harvesting of products from plants in the wild is widespread throughout southern Africa. Particularly important products are plant parts used in traditional medicine. However, the impacts of harvesting practices are rarely quantified, with as yet insufficient generic rules across species and life forms. This limits the predictive ability to monitor and manage the affected populations. This paper examines the harvesting impact on two popular woody medicinal species used throughout sub-Saharan Africa, namely Catha edulis (Vahl) Forssk. ex Endl. (bushman’s tea) and Rapanea melanophloeos (L.) Mez. (Cape beech). In both species, basal diameters, heights, and the number of size classes in the harvested populations were lower than in unharvested. Densities of harvested populations were higher in both species, including densities of young plants, but the frequency of individuals in larger size classes was lower. The populations of both species being harvested for medicinal products appeared to be withstanding the current levels of harvesting, but the population structure of C. edulis populations being harvested for poles on the roadside and near human settlements had been substantially altered. Despite the resilience of the two species to harvesting for medicinal products, loss of habitat or changes in land use pose a threat to a number of the assessed populations.
- Full Text:
- Date Issued: 2004
Hill of Fools: a South African Romeo and Juliet?
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7039 , http://hdl.handle.net/10962/d1007377 , http://hdl.handle.net/10520/EJC47866
- Description: preprint , What kind of debt does Hill of Fools owe to Shakespeare? Look up ‘Peteni’ in the Companion to South African English Literature (1986) and you will be told that Hill of Fools is “loosely based on the story of Romeo and Juliet” (155). Scan the first newspaper reviews (see “The Early Reception of Hill of Fools” in this volume) and it is noticeable that a great many journalists focus on the Shakespeare connection as a means of introducing the book to their readers. One of the publisher’s readers, Henry Chakava, urged before publication that once all references to tribe or tribalism had been excised “the result will be a Romeo and Juliet type story much more superior to Weep Not Child.” The author himself reportedly described the book as “a black Romeo and Juliet drama” (Tribune Reporter 1988). And, indeed, some kind of parallel is patent to anyone who reads Hill of Fools with Shakespeare’s play in mind.
- Full Text:
- Date Issued: 2004
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7039 , http://hdl.handle.net/10962/d1007377 , http://hdl.handle.net/10520/EJC47866
- Description: preprint , What kind of debt does Hill of Fools owe to Shakespeare? Look up ‘Peteni’ in the Companion to South African English Literature (1986) and you will be told that Hill of Fools is “loosely based on the story of Romeo and Juliet” (155). Scan the first newspaper reviews (see “The Early Reception of Hill of Fools” in this volume) and it is noticeable that a great many journalists focus on the Shakespeare connection as a means of introducing the book to their readers. One of the publisher’s readers, Henry Chakava, urged before publication that once all references to tribe or tribalism had been excised “the result will be a Romeo and Juliet type story much more superior to Weep Not Child.” The author himself reportedly described the book as “a black Romeo and Juliet drama” (Tribune Reporter 1988). And, indeed, some kind of parallel is patent to anyone who reads Hill of Fools with Shakespeare’s play in mind.
- Full Text:
- Date Issued: 2004
Hill of Fools: notes towards a publishing history
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7037 , http://hdl.handle.net/10962/d1007373 , http://hdl.handle.net/10520/EJC47868
- Description: preprint , Written in English in the early 70s, Hill of Fools was projected into the market for world literature among distinguished company in the Heinemann African Writers Series (HAWS), at a time when expectations for African writing in English reflected a certain orthodoxy; when the book’s origins in apartheid South Africa pressed certain ‘buttons’ in world readerships, and when the country’s increasing cultural isolation meant that even relatively well-versed literary Africanists were less than familiar with the milieu from which the story springs. The result has been that the novel acquired a rather odd penumbra of interpretation, ranging from the naïve to the dismissive or reductive.
- Full Text:
- Date Issued: 2004
- Authors: Wright, Laurence
- Date: 2004
- Language: English
- Type: text , article
- Identifier: vital:7037 , http://hdl.handle.net/10962/d1007373 , http://hdl.handle.net/10520/EJC47868
- Description: preprint , Written in English in the early 70s, Hill of Fools was projected into the market for world literature among distinguished company in the Heinemann African Writers Series (HAWS), at a time when expectations for African writing in English reflected a certain orthodoxy; when the book’s origins in apartheid South Africa pressed certain ‘buttons’ in world readerships, and when the country’s increasing cultural isolation meant that even relatively well-versed literary Africanists were less than familiar with the milieu from which the story springs. The result has been that the novel acquired a rather odd penumbra of interpretation, ranging from the naïve to the dismissive or reductive.
- Full Text:
- Date Issued: 2004
How can a potential franchisor establish a successful franchise in fast moving consumer goods
- Authors: Esmeraldo, Rosa
- Date: 2004
- Subjects: Franchises (Retail trade) -- South Africa , Franchises (Retail trade) -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10872 , http://hdl.handle.net/10948/235 , Franchises (Retail trade) -- South Africa , Franchises (Retail trade) -- Management
- Description: Franchising has become the latest trend in business expansion and business acquisition and with the South African franchising market estimated at being around 12% and growing rapidly, enormous potential for future growth is indicated. Companies both local and international are seeking franchise expansion opportunities in Africa despite the higher risks. The significance of implementing franchises into Africa is the filtering down of business opportunities to the small and medium enterprise sector. It can be said that franchising promotes business growth and private ownership, while improving the quality of life of the poor through its impact on income and employment. A franchise organisation that grows too quickly might not have the necessary ‘factors’ in place to support all of the units properly. In the survey conducted, it was indicated that the franchise business practice echoed the literature reviewed. All the steps necessary to establish a franchise are important but not necessarily as equal. The more matured franchisee needed less guidance from the franchisor and relied more on the business concept and location. Potential franchisors need to take the necessary steps to establish a franchise and treat each step as an important part of the franchise process.
- Full Text:
- Date Issued: 2004
- Authors: Esmeraldo, Rosa
- Date: 2004
- Subjects: Franchises (Retail trade) -- South Africa , Franchises (Retail trade) -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10872 , http://hdl.handle.net/10948/235 , Franchises (Retail trade) -- South Africa , Franchises (Retail trade) -- Management
- Description: Franchising has become the latest trend in business expansion and business acquisition and with the South African franchising market estimated at being around 12% and growing rapidly, enormous potential for future growth is indicated. Companies both local and international are seeking franchise expansion opportunities in Africa despite the higher risks. The significance of implementing franchises into Africa is the filtering down of business opportunities to the small and medium enterprise sector. It can be said that franchising promotes business growth and private ownership, while improving the quality of life of the poor through its impact on income and employment. A franchise organisation that grows too quickly might not have the necessary ‘factors’ in place to support all of the units properly. In the survey conducted, it was indicated that the franchise business practice echoed the literature reviewed. All the steps necessary to establish a franchise are important but not necessarily as equal. The more matured franchisee needed less guidance from the franchisor and relied more on the business concept and location. Potential franchisors need to take the necessary steps to establish a franchise and treat each step as an important part of the franchise process.
- Full Text:
- Date Issued: 2004
How the South African print media cover economics news: a study of inflation news in four newspapers, 1999-2001
- Authors: Kula, Momelezi Michael
- Date: 2004
- Subjects: Journalism, Commercial -- South Africa , Inflation (Finance) -- South Africa , South Africa -- Newspapers , Mass media -- Political aspects -- Africa , Democracy , Journalism -- Social aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3450 , http://hdl.handle.net/10962/d1002904 , Journalism, Commercial -- South Africa , Inflation (Finance) -- South Africa , South Africa -- Newspapers , Mass media -- Political aspects -- Africa , Democracy , Journalism -- Social aspects
- Description: There is a considerable amount of literature arguing that economics and business journalism is growing. This subfield of journalism is important as economics issues impact on everyday lives of the people. Media have an important role to inform people about the economy and give them a voice to take part in public debates. The down side though is that economics journalism is criticised for not serving the public well in this aspect. Evidence suggests that economics journalism lost its critical character and that there is closer in economics debates. Using content analysis, this study examines coverage of inflation as reported by South African print media. Three major findings emerged: 1) Evidence shows that there are a variety of cases of inflation. 2) There are also similarities among newspapers on what they view as causing inflation. 3) However, media do not draw sources from all sectors of society. The elite, who are educated people and government officials, are over-accessed while the ordinary citizens - although also affected by inflation – are marginalized. Company and government sources top source lists in the media. It is argued that sources play an important role in shaping the news content. They do so by identifying problems and prescribing potential solutions. They set parameters and define terms of reference. However, media also play a mediating role. They do so by selecting sources and structuring sources in stories. They may chose to quote or report what their sources say and even comment on it. This study concludes that in South Africa ordinary citizens have no voices in economics debates. Media used bureaucratic sources only and that is a consonant agenda on inflation coverage amongst newspapers. The heavy reliance on bureaucratic sources and the exclusion of some sectors of society in sources lists raises questions about impartiality of these sources on issues relating to their organisations and institutions. These are not viable sources that could provide information that could expose abuse of power.
- Full Text:
- Date Issued: 2004
- Authors: Kula, Momelezi Michael
- Date: 2004
- Subjects: Journalism, Commercial -- South Africa , Inflation (Finance) -- South Africa , South Africa -- Newspapers , Mass media -- Political aspects -- Africa , Democracy , Journalism -- Social aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3450 , http://hdl.handle.net/10962/d1002904 , Journalism, Commercial -- South Africa , Inflation (Finance) -- South Africa , South Africa -- Newspapers , Mass media -- Political aspects -- Africa , Democracy , Journalism -- Social aspects
- Description: There is a considerable amount of literature arguing that economics and business journalism is growing. This subfield of journalism is important as economics issues impact on everyday lives of the people. Media have an important role to inform people about the economy and give them a voice to take part in public debates. The down side though is that economics journalism is criticised for not serving the public well in this aspect. Evidence suggests that economics journalism lost its critical character and that there is closer in economics debates. Using content analysis, this study examines coverage of inflation as reported by South African print media. Three major findings emerged: 1) Evidence shows that there are a variety of cases of inflation. 2) There are also similarities among newspapers on what they view as causing inflation. 3) However, media do not draw sources from all sectors of society. The elite, who are educated people and government officials, are over-accessed while the ordinary citizens - although also affected by inflation – are marginalized. Company and government sources top source lists in the media. It is argued that sources play an important role in shaping the news content. They do so by identifying problems and prescribing potential solutions. They set parameters and define terms of reference. However, media also play a mediating role. They do so by selecting sources and structuring sources in stories. They may chose to quote or report what their sources say and even comment on it. This study concludes that in South Africa ordinary citizens have no voices in economics debates. Media used bureaucratic sources only and that is a consonant agenda on inflation coverage amongst newspapers. The heavy reliance on bureaucratic sources and the exclusion of some sectors of society in sources lists raises questions about impartiality of these sources on issues relating to their organisations and institutions. These are not viable sources that could provide information that could expose abuse of power.
- Full Text:
- Date Issued: 2004
I am going home
- Nduna, S., Xakayi, S., Rodolo, L. S., Mgidi, A., Magibisela, J., Nduma, S., Dubeni, T., Hangana, S., Composer not specified, Dargie, Dave
- Authors: Nduna, S. , Xakayi, S. , Rodolo, L. S. , Mgidi, A. , Magibisela, J. , Nduma, S. , Dubeni, T. , Hangana, S. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: IsiXhosa
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343185 , vital:62978 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344a-06
- Description: UFH music students accompanied by different types of marimba
- Full Text: false
- Date Issued: 2004
- Authors: Nduna, S. , Xakayi, S. , Rodolo, L. S. , Mgidi, A. , Magibisela, J. , Nduma, S. , Dubeni, T. , Hangana, S. , Composer not specified , Dargie, Dave
- Date: 2004
- Subjects: Folk music , Sacred music , Field recordings , Africa, Sub-Saharan , Africa South Africa Alice sa
- Language: IsiXhosa
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/343185 , vital:62978 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DDC344a-06
- Description: UFH music students accompanied by different types of marimba
- Full Text: false
- Date Issued: 2004
iLanga: A next generation VOIP-based, TDM-enabled PBX
- Authors: Penton J , Terzoli, Alfredo
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427591 , vital:72449 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228963823_iLanga_a_next_generation_VoIP-based_TDM-enabled_PBX/links/02bfe51344c9db1c75000000/iLanga-a-next-generation-VoIP-based-TDM-enabled-PBX.pdf
- Description: iLanga is a complete, cost-effective, computer-based PBX built and be-ing prepared as a commercial product at Rhodes University. Running on a single PC (in its minimal configuration), iLanga provides all the fea-tures of a conventional PBX together with full support for VoIP. In this paper we introduce and discuss iLanga’s architecture, emphasising its main components, Asterisk, SIP Express Router (SER) and OpenH323 Gatekeeper (OpenGK). We also discuss the development of new ser-vices and features in iLanga as well as the possibility to manage and customize it. The paper concludes with the description of a pilot de-ployment of iLanga that we are using to test and refine the system.
- Full Text:
- Date Issued: 2004
- Authors: Penton J , Terzoli, Alfredo
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427591 , vital:72449 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228963823_iLanga_a_next_generation_VoIP-based_TDM-enabled_PBX/links/02bfe51344c9db1c75000000/iLanga-a-next-generation-VoIP-based-TDM-enabled-PBX.pdf
- Description: iLanga is a complete, cost-effective, computer-based PBX built and be-ing prepared as a commercial product at Rhodes University. Running on a single PC (in its minimal configuration), iLanga provides all the fea-tures of a conventional PBX together with full support for VoIP. In this paper we introduce and discuss iLanga’s architecture, emphasising its main components, Asterisk, SIP Express Router (SER) and OpenH323 Gatekeeper (OpenGK). We also discuss the development of new ser-vices and features in iLanga as well as the possibility to manage and customize it. The paper concludes with the description of a pilot de-ployment of iLanga that we are using to test and refine the system.
- Full Text:
- Date Issued: 2004
Imagery and the transformation of meaning in psychotherapy for post-traumatic stress disorder: a hermeneutic case study
- Authors: Karpelowsky, Belinda Jodi
- Date: 2004
- Subjects: Post-traumatic stress disorder -- Treatment , Post-traumatic stress disorder -- Rehabilitation , Imagery (Psychology) -- Therapeutic use , Psychotherapy , Post-traumatic stress disorder -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3000 , http://hdl.handle.net/10962/d1002509 , Post-traumatic stress disorder -- Treatment , Post-traumatic stress disorder -- Rehabilitation , Imagery (Psychology) -- Therapeutic use , Psychotherapy , Post-traumatic stress disorder -- Case studies
- Description: This study discusses the assessment and treatment of a 21-year old male who had suffered multiple traumas, which had culminated in the death of his younger brother. He presented with Acute Stress Disorder. The literature review examines a diverse range of theorists and discourses, that have addressed the psychological consequences of trauma and highlights the complexity of the phenomena involved. The case study, located in the South African context, aims to sensitise the reader to the unique dilemmas facing each trauma survivor, and serves to highlight specifically those areas, which are pertinent and further more contribute significantly to the recovery process. The case narrative consists of a detailed synopsis of the therapy process, extracted from the session record notes documented at the time. Several other sources of information, including contributions from the participant, were used to verify and validate the accuracy of the data included. The narrative is written in a style that conveys the intensity of the nature of trauma work and the manner in which both patient and clinician are frequently confronted with very difficult emotional work. Finally the discussion examines the case narrative through the use of a set of carefully selected hermeneutic questions. These focused on (I) key concepts from the work of Robert Lifton who highlights the existential dimensions of the impact of trauma; (2) the role of the image in encapsulating the complex traumatic and post-traumatic experience of the survivor as well as facilitating the emotional processing of the trauma is examined; (3) the contribution to the process of therapy of aspects of the therapeutic relationship; and (4) the concept of recovery in relation to the question of what constitutes 'trauma work'. In conclusion, several meta-theoretical issues related to trauma, the strengths and weaknesses inherent to the research and relevant future areas of research are highlighted.
- Full Text:
- Date Issued: 2004
- Authors: Karpelowsky, Belinda Jodi
- Date: 2004
- Subjects: Post-traumatic stress disorder -- Treatment , Post-traumatic stress disorder -- Rehabilitation , Imagery (Psychology) -- Therapeutic use , Psychotherapy , Post-traumatic stress disorder -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3000 , http://hdl.handle.net/10962/d1002509 , Post-traumatic stress disorder -- Treatment , Post-traumatic stress disorder -- Rehabilitation , Imagery (Psychology) -- Therapeutic use , Psychotherapy , Post-traumatic stress disorder -- Case studies
- Description: This study discusses the assessment and treatment of a 21-year old male who had suffered multiple traumas, which had culminated in the death of his younger brother. He presented with Acute Stress Disorder. The literature review examines a diverse range of theorists and discourses, that have addressed the psychological consequences of trauma and highlights the complexity of the phenomena involved. The case study, located in the South African context, aims to sensitise the reader to the unique dilemmas facing each trauma survivor, and serves to highlight specifically those areas, which are pertinent and further more contribute significantly to the recovery process. The case narrative consists of a detailed synopsis of the therapy process, extracted from the session record notes documented at the time. Several other sources of information, including contributions from the participant, were used to verify and validate the accuracy of the data included. The narrative is written in a style that conveys the intensity of the nature of trauma work and the manner in which both patient and clinician are frequently confronted with very difficult emotional work. Finally the discussion examines the case narrative through the use of a set of carefully selected hermeneutic questions. These focused on (I) key concepts from the work of Robert Lifton who highlights the existential dimensions of the impact of trauma; (2) the role of the image in encapsulating the complex traumatic and post-traumatic experience of the survivor as well as facilitating the emotional processing of the trauma is examined; (3) the contribution to the process of therapy of aspects of the therapeutic relationship; and (4) the concept of recovery in relation to the question of what constitutes 'trauma work'. In conclusion, several meta-theoretical issues related to trauma, the strengths and weaknesses inherent to the research and relevant future areas of research are highlighted.
- Full Text:
- Date Issued: 2004
Implementing an activity-based costing model
- Authors: Cohen, Howard
- Date: 2004
- Subjects: Activity-based costing , Managerial accounting
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8970 , http://hdl.handle.net/10948/240 , Activity-based costing , Managerial accounting
- Description: Activity-based costing (ABC) is a forward-looking product costing method. Unlike traditional volume-based approaches, which are historically oriented, ABC concepts guide managers in seeking the best strategies to pursue in the future. This product costing method can be a valuable tool in planning and managing costs not only in the manufacturing area, but also in all aspects of business operations, from product design to distribution. Although its main advantage is its ability to provide more realistic product cost information for financial reporting purposes, use of ABC can lead to a better understanding of the strategic linkages existing between the various cost areas in the organisation. It enables managers to have a holistic view of cost management. ABC was developed to better understand, manage and control the overheads. The brief fundamental of ABC is: Products consume activities, activities consume resources, and resources consume costs. Based upon this fundamental principle, ABC can trace the cost from resources to activities that are consumed by product manufacturing processes as well as from activities to products. ABC investigates the transactions that trigger cost instead of concentrating solely on measures of physical volume or a certain amount of labour hours. Compared to the traditional costing systems, ABC can not only answer how much product cost is but also tell executives the factors triggering costs and the way to manage costs. ABC helps managers make better decisions about product design, pricing, marketing, and mix and encourages continual improvement. Unlike the traditional method, instead of using the single pre-determined overhead rate to absorb the indirect cost to products, ABC uses actual incurred cost to v determine the product cost. By tracing the absorption process of indirect cost, ABC would provide more information to management and help it find better ways to manage costs. However, the cost drivers used in ABC are constants but the cost driver rates are continually changing. ABC still uses predetermined cost drivers so it has the same fundamental problem as the traditional methods for estimating.
- Full Text:
- Date Issued: 2004
- Authors: Cohen, Howard
- Date: 2004
- Subjects: Activity-based costing , Managerial accounting
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8970 , http://hdl.handle.net/10948/240 , Activity-based costing , Managerial accounting
- Description: Activity-based costing (ABC) is a forward-looking product costing method. Unlike traditional volume-based approaches, which are historically oriented, ABC concepts guide managers in seeking the best strategies to pursue in the future. This product costing method can be a valuable tool in planning and managing costs not only in the manufacturing area, but also in all aspects of business operations, from product design to distribution. Although its main advantage is its ability to provide more realistic product cost information for financial reporting purposes, use of ABC can lead to a better understanding of the strategic linkages existing between the various cost areas in the organisation. It enables managers to have a holistic view of cost management. ABC was developed to better understand, manage and control the overheads. The brief fundamental of ABC is: Products consume activities, activities consume resources, and resources consume costs. Based upon this fundamental principle, ABC can trace the cost from resources to activities that are consumed by product manufacturing processes as well as from activities to products. ABC investigates the transactions that trigger cost instead of concentrating solely on measures of physical volume or a certain amount of labour hours. Compared to the traditional costing systems, ABC can not only answer how much product cost is but also tell executives the factors triggering costs and the way to manage costs. ABC helps managers make better decisions about product design, pricing, marketing, and mix and encourages continual improvement. Unlike the traditional method, instead of using the single pre-determined overhead rate to absorb the indirect cost to products, ABC uses actual incurred cost to v determine the product cost. By tracing the absorption process of indirect cost, ABC would provide more information to management and help it find better ways to manage costs. However, the cost drivers used in ABC are constants but the cost driver rates are continually changing. ABC still uses predetermined cost drivers so it has the same fundamental problem as the traditional methods for estimating.
- Full Text:
- Date Issued: 2004
In conversation with Barney: a critical discourse analysis of interaction between a child with autism and his co-participants
- Authors: Geils, Catherine
- Date: 2004
- Subjects: Autism in children -- Case studies , Autistic children , Autistic children -- Rehabilitation , Discourse analysis , Children and adults , Language acquisition , Conversation , Children -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2980 , http://hdl.handle.net/10962/d1002489 , Autism in children -- Case studies , Autistic children , Autistic children -- Rehabilitation , Discourse analysis , Children and adults , Language acquisition , Conversation , Children -- Language
- Description: My study arose in the context of an intervention programme aimed at the development of a child with autism’s communication and social interaction skills. The approach I take is a social constructionist one in which language is considered to be constructive and constitutive of social and psychological reality. This orientation challenges the assumptions of a western psychiatric approach that emphasizes the impairment and deficits associated with autism. The participants of the study are a 6-year-old boy diagnosed with Pervasive Developmental Disorder (Autistic Spectrum), and his mother, father, sister and a volunteer on the intervention programme. The discourse analytic method of conversation analysis is employed as a means of elucidating the collaborative mechanisms employed by both the child and his co-participants in making sense of one another. The specific aims of the study are to closely examine the communicative behaviour and interactive styles of the child and his coparticipants, their implications for communicative success (co-ordinated interaction) or breakdown (discordant interaction), and the implications for how the child is positioned within the discourse in relation to his co-participants. My constructions of the data suggested that a playful, activity-based interactive style constituted by non-verbal turns, affection and short, simple utterances enhance mutual participation and the accomplishment of co-ordinated interaction. Barney’s co-participants sometimes tend to dominate interaction and frequently employ a strategy of repetitive questioning, which functions to direct and constrain the interaction and results in the child’s withdrawal and discordant interaction. This tendency to withdraw, however, seems to function as a means by which the child is able to actively resist positioning by others, and thus constitutes himself in a position of greater power. Furthermore, his use of the pronoun ‘I’ and collaborative negotiation of the words yours and mine suggest the active co-construction and positioning of himself as a separate person in relation to his co-participants. This research informs intervention efforts and encourages the co-participants to reflect on how interaction is co-constructed between themselves and the child.
- Full Text:
- Date Issued: 2004
- Authors: Geils, Catherine
- Date: 2004
- Subjects: Autism in children -- Case studies , Autistic children , Autistic children -- Rehabilitation , Discourse analysis , Children and adults , Language acquisition , Conversation , Children -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2980 , http://hdl.handle.net/10962/d1002489 , Autism in children -- Case studies , Autistic children , Autistic children -- Rehabilitation , Discourse analysis , Children and adults , Language acquisition , Conversation , Children -- Language
- Description: My study arose in the context of an intervention programme aimed at the development of a child with autism’s communication and social interaction skills. The approach I take is a social constructionist one in which language is considered to be constructive and constitutive of social and psychological reality. This orientation challenges the assumptions of a western psychiatric approach that emphasizes the impairment and deficits associated with autism. The participants of the study are a 6-year-old boy diagnosed with Pervasive Developmental Disorder (Autistic Spectrum), and his mother, father, sister and a volunteer on the intervention programme. The discourse analytic method of conversation analysis is employed as a means of elucidating the collaborative mechanisms employed by both the child and his co-participants in making sense of one another. The specific aims of the study are to closely examine the communicative behaviour and interactive styles of the child and his coparticipants, their implications for communicative success (co-ordinated interaction) or breakdown (discordant interaction), and the implications for how the child is positioned within the discourse in relation to his co-participants. My constructions of the data suggested that a playful, activity-based interactive style constituted by non-verbal turns, affection and short, simple utterances enhance mutual participation and the accomplishment of co-ordinated interaction. Barney’s co-participants sometimes tend to dominate interaction and frequently employ a strategy of repetitive questioning, which functions to direct and constrain the interaction and results in the child’s withdrawal and discordant interaction. This tendency to withdraw, however, seems to function as a means by which the child is able to actively resist positioning by others, and thus constitutes himself in a position of greater power. Furthermore, his use of the pronoun ‘I’ and collaborative negotiation of the words yours and mine suggest the active co-construction and positioning of himself as a separate person in relation to his co-participants. This research informs intervention efforts and encourages the co-participants to reflect on how interaction is co-constructed between themselves and the child.
- Full Text:
- Date Issued: 2004
In situ feeding rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, in a temperate, temporarily open/closed Eastern Cape estuary
- Authors: Froneman, P William
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
- Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
- Full Text:
- Date Issued: 2004
- Authors: Froneman, P William
- Date: 2004
- Language: English
- Type: text , Article
- Identifier: vital:6901 , http://hdl.handle.net/10962/d1011754
- Description: Size-fractionated chlorophyll-a (chl-a) concentrations and the in situ grazing rates of the copepods, Pseudodiaptomus hessei and Acartia longipatella, were assessed seasonally at the temporarily open/closed Kasouga estuary situated along the southeast coast of southern Africa. Total integrated chl-a concentration ranged between 1.17 and 12.18 mg chl-a m^(–3) and was always dominated by small phytoplankton cells (<20 μm), which comprised up to 86% (range 64–86%) of the total pigment. Total zooplankton abundance ranged between 2676 and 62 043 individuals m^(–3). These copepods numerically dominated the zooplankton counts, accounting for between 79% and 91% of the total. Gut pigment concentrations of the two species at night were significantly higher than the daytime values (P<0.05 in all cases). The observed pattern could be related to the marked diurnal vertical migration patterns exhibited by the copepods. Gut evacuation rates of P. hessei during the study ranged between 0.29 and 0.77 h^(–1) and between 0.39 and 0.58 h^(–1) for A. longipatella. The rate of gut pigment destruction for P. hessei and A. longipatella ranged between 55% and 81% and between 88% and 92% of the total chl-a ingested, respectively. The combined grazing impact of the two copepods ranged between 0.65 and 4.37 mg chl-a m^(–3), or between 4.3% and 35.9% of the available chl-a in the water column. Variations in the grazing activity of the two species could be attributed largely to seasonality in water temperature and shifts in the phytoplankton community structure and zooplankton abundance.
- Full Text:
- Date Issued: 2004
In vitro anti-HIV activities of Sutherlandia frutescens and Lobostemon trigonum extracts
- Authors: Harnett, Siobhán Margaret
- Date: 2004
- Subjects: Medicinal plants -- South Africa , Materia medica, Vegetable -- South Africa , HIV infections -- Alternative treatment -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:11072 , http://hdl.handle.net/10948/347 , Medicinal plants -- South Africa , Materia medica, Vegetable -- South Africa , HIV infections -- Alternative treatment -- South Africa
- Description: Currently, the approved anti-HIV drugs on the market only target the three HIV enzymes: reverse transcriptase, protease and more recently, integrase. Due to the limited nature of the current therapy, it is possible that a multi-drug resistant virus can emerge. The main concerns in developing countries however, are the expense and availability of the drugs and because of this, it is essential to investigate all alternatives. Traditional medicine offers many advantages as compared to allopathic treatment in so far as being relatively cheaper, accessible and it is broadly accepted in the population groups of the developing countries. Little is known though, of the exact efficacy and toxicity of these remedies so it is vital that these possible leads be investigated thoroughly. For the purpose of this study, two plants, Sutherlandia frutescens and Lobostemon trigonum were studied to ascertain their potential anti-HIV activity. Sutherlandia has received international attention as a possible cheap herbal remedy to improve the health of AIDS sufferers. Anecdotal evidence from health workers claim that HIV- infected patients on Sutherlandia treatment have shown improved CD4 counts, decreased viral loads and a general improvement in well-being. Extracts were prepared from dried leaves and flowers in methanol, ethanol, acetone, methylene dichloride or distilled water. Sulphated polysaccharides have been described extensively in literature with regards to their anti-HIV activity, so as a form of dereplication; an ethanol precipitation was performed on the aqueous extracts to remove sulphated polysaccharides. A toxicity study was performed on all crude extracts using uninfected peripheral mononuclear blood cells (PBMCs) isolated from whole blood. To measure anti-HIV activity, HIV-infected PBMCs were cultured with each of the crude extracts and cell viability measured using the tetrazolium salt, XTT. HIV-infected CEM-NKR-CCR5 cells were also used and supernatant from the viral studies was tested for the HIV antigen p24. xii Results varied greatly between assays but with the inclusion of a point-scale system to evaluate the extracts it was clear that overall the organic extracts of the Sutherlandia flowers, especially the acetone extract (SFA), showed great anti-HIV potential. SFA in every case decreased p24 levels and in the toxicity study did not decrease cell proliferation. With the HIV-infected PBMCs SFA actually helped improve cell proliferation despite the infection. To determine the specific anti- HIV activity, all crude extracts were tested for inhibition of HIV-I reverse transcriptase, the glycohydrolase enzymes: a-glucosidase, ß-glucosidase, ßglucuronidase, HIV-I integrase and HIV-II protease. No significant inhibition was seen with these experiments except for the HIV-I RT assay. The aqueous extract of the Lobostemon leaves produced an inhibitor of HIV-RT with a very low IC50 value of 0.049mg/ml. Some inhibitory effect was lost with the removal of the sulphated polysaccharides and the addition of BSA to the assay, but still 64% inhibition of the HIVRT remained, which confirmed that the inhibitor could be something novel, and not of the polysaccharide or tannin compounds.
- Full Text:
- Date Issued: 2004
- Authors: Harnett, Siobhán Margaret
- Date: 2004
- Subjects: Medicinal plants -- South Africa , Materia medica, Vegetable -- South Africa , HIV infections -- Alternative treatment -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:11072 , http://hdl.handle.net/10948/347 , Medicinal plants -- South Africa , Materia medica, Vegetable -- South Africa , HIV infections -- Alternative treatment -- South Africa
- Description: Currently, the approved anti-HIV drugs on the market only target the three HIV enzymes: reverse transcriptase, protease and more recently, integrase. Due to the limited nature of the current therapy, it is possible that a multi-drug resistant virus can emerge. The main concerns in developing countries however, are the expense and availability of the drugs and because of this, it is essential to investigate all alternatives. Traditional medicine offers many advantages as compared to allopathic treatment in so far as being relatively cheaper, accessible and it is broadly accepted in the population groups of the developing countries. Little is known though, of the exact efficacy and toxicity of these remedies so it is vital that these possible leads be investigated thoroughly. For the purpose of this study, two plants, Sutherlandia frutescens and Lobostemon trigonum were studied to ascertain their potential anti-HIV activity. Sutherlandia has received international attention as a possible cheap herbal remedy to improve the health of AIDS sufferers. Anecdotal evidence from health workers claim that HIV- infected patients on Sutherlandia treatment have shown improved CD4 counts, decreased viral loads and a general improvement in well-being. Extracts were prepared from dried leaves and flowers in methanol, ethanol, acetone, methylene dichloride or distilled water. Sulphated polysaccharides have been described extensively in literature with regards to their anti-HIV activity, so as a form of dereplication; an ethanol precipitation was performed on the aqueous extracts to remove sulphated polysaccharides. A toxicity study was performed on all crude extracts using uninfected peripheral mononuclear blood cells (PBMCs) isolated from whole blood. To measure anti-HIV activity, HIV-infected PBMCs were cultured with each of the crude extracts and cell viability measured using the tetrazolium salt, XTT. HIV-infected CEM-NKR-CCR5 cells were also used and supernatant from the viral studies was tested for the HIV antigen p24. xii Results varied greatly between assays but with the inclusion of a point-scale system to evaluate the extracts it was clear that overall the organic extracts of the Sutherlandia flowers, especially the acetone extract (SFA), showed great anti-HIV potential. SFA in every case decreased p24 levels and in the toxicity study did not decrease cell proliferation. With the HIV-infected PBMCs SFA actually helped improve cell proliferation despite the infection. To determine the specific anti- HIV activity, all crude extracts were tested for inhibition of HIV-I reverse transcriptase, the glycohydrolase enzymes: a-glucosidase, ß-glucosidase, ßglucuronidase, HIV-I integrase and HIV-II protease. No significant inhibition was seen with these experiments except for the HIV-I RT assay. The aqueous extract of the Lobostemon leaves produced an inhibitor of HIV-RT with a very low IC50 value of 0.049mg/ml. Some inhibitory effect was lost with the removal of the sulphated polysaccharides and the addition of BSA to the assay, but still 64% inhibition of the HIVRT remained, which confirmed that the inhibitor could be something novel, and not of the polysaccharide or tannin compounds.
- Full Text:
- Date Issued: 2004
Indigenous trauma volunteers: survivors with a mission
- Authors: Moultrie, Alison
- Date: 2004
- Subjects: Volunteers -- Job stress , Volunteer workers in community development -- Job stress , Stress (Psychology) , Psychic trauma , Burn out (Psychology)
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3027 , http://hdl.handle.net/10962/d1002536 , Volunteers -- Job stress , Volunteer workers in community development -- Job stress , Stress (Psychology) , Psychic trauma , Burn out (Psychology)
- Description: There is a growing body of literature on the risk for secondary trauma amongst professional trauma workers. Nonetheless, there is scant published literature on the impact of trauma work on volunteers; particularly when such volunteers are indigenous to the highly traumatized communities which they serve. The study examined a group of parents (N=16) who volunteered in a school-based trauma support project in an impoverished, gang-ridden South African urban community in which they themselves reside. Aims were to 1) Explore the psychological impact of indigenous trauma volunteerism; 2) Explore volunteers’ perceptions of costs and benefits of volunteerism. Data collection was chiefly qualitative, using focus group and individual interviews. The Professional Quality of Life: Compassion Satisfaction and Fatigue Subscales (Stamm, 2002) were administered in order to determine risk for burnout, risk for compassion fatigue and potential for compassion satisfaction. The Stressful Life Experiences Screening Short Form (Stamm, 1997) was administered in order to gather descriptive information regarding personal trauma histories. Project documentation was reviewed. Analysis and interpretation of qualitative data involved a combination of both etic (theory-based) and emic (data and context-based) techniques. The volunteers’ experiences were co-constructed in interaction with three settings: 1) Experiences of training and supervision were affirming and empowering; 2) Experiences of the school context were mediated by the degree of access and integration into the school environment; 3) Experiences of the community context were mediated by the dynamics of identification, role fluidity and inter-setting negotiation. The primary cost of involvement was distress relating to limitations on capacity to help fellow community members with whom they strongly identified, and whom they felt intrapsychically, interpersonally and socially pressured to assist. These limitations included limited client resources, limited personal resources, limited occupational resources and limited systemic resources. Other sources of distress included context-related boundary management difficulties, institutional (school-related) stressors, difficulties in persuading children to disclose abuse and material costs of volunteering. Coping was facilitated by empowering training, supervision, peer support, and self-care practices. Benefits included acquisition of psychological, interpersonal and occupational skills, improved personal relationships, social support, validation, personal healing and role satisfaction.
- Full Text:
- Date Issued: 2004
- Authors: Moultrie, Alison
- Date: 2004
- Subjects: Volunteers -- Job stress , Volunteer workers in community development -- Job stress , Stress (Psychology) , Psychic trauma , Burn out (Psychology)
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3027 , http://hdl.handle.net/10962/d1002536 , Volunteers -- Job stress , Volunteer workers in community development -- Job stress , Stress (Psychology) , Psychic trauma , Burn out (Psychology)
- Description: There is a growing body of literature on the risk for secondary trauma amongst professional trauma workers. Nonetheless, there is scant published literature on the impact of trauma work on volunteers; particularly when such volunteers are indigenous to the highly traumatized communities which they serve. The study examined a group of parents (N=16) who volunteered in a school-based trauma support project in an impoverished, gang-ridden South African urban community in which they themselves reside. Aims were to 1) Explore the psychological impact of indigenous trauma volunteerism; 2) Explore volunteers’ perceptions of costs and benefits of volunteerism. Data collection was chiefly qualitative, using focus group and individual interviews. The Professional Quality of Life: Compassion Satisfaction and Fatigue Subscales (Stamm, 2002) were administered in order to determine risk for burnout, risk for compassion fatigue and potential for compassion satisfaction. The Stressful Life Experiences Screening Short Form (Stamm, 1997) was administered in order to gather descriptive information regarding personal trauma histories. Project documentation was reviewed. Analysis and interpretation of qualitative data involved a combination of both etic (theory-based) and emic (data and context-based) techniques. The volunteers’ experiences were co-constructed in interaction with three settings: 1) Experiences of training and supervision were affirming and empowering; 2) Experiences of the school context were mediated by the degree of access and integration into the school environment; 3) Experiences of the community context were mediated by the dynamics of identification, role fluidity and inter-setting negotiation. The primary cost of involvement was distress relating to limitations on capacity to help fellow community members with whom they strongly identified, and whom they felt intrapsychically, interpersonally and socially pressured to assist. These limitations included limited client resources, limited personal resources, limited occupational resources and limited systemic resources. Other sources of distress included context-related boundary management difficulties, institutional (school-related) stressors, difficulties in persuading children to disclose abuse and material costs of volunteering. Coping was facilitated by empowering training, supervision, peer support, and self-care practices. Benefits included acquisition of psychological, interpersonal and occupational skills, improved personal relationships, social support, validation, personal healing and role satisfaction.
- Full Text:
- Date Issued: 2004
Induced ovulation, spawning, egg incubation, and hatching of the cyprinid fish Labeo victorianus in captivity
- Rutaisire, Justus, Booth, Anthony J
- Authors: Rutaisire, Justus , Booth, Anthony J
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124789 , vital:35697 , https://doi.10.1111/j.1749-7345.2004.tb00102.x
- Description: Ningu Lubeo victorianus is the only labeine fish within Lake Victoria and its catchment (Greenwood 1966; Reid 1985). This species, once widely distributed in the Lake Victoria basin and supporting a commercial fishery until the late 195Os, has declined due to overfishing (Cadwalladr 1965; Ogutu-Ohwayo 1990; Seehausen 1996). The L. victorianus fishery has not only collapsed but the species has also disappeared from some of its former habitats. Recent surveys in Uganda have only found two distant populations-one in the Sio River on the Uganda-Kenya border (0” I3’53”N, 34”00’30’E), and the second in the Kagera River on the Uganda-Tanzania border (0°56’28.1”S, 3 1’46’ 18”E) (Rutaisire 2003) (Fig. 1). Currently, there is growing interest to breed the fish for wild stock enhancement and culture as a food fish.
- Full Text:
- Date Issued: 2004
- Authors: Rutaisire, Justus , Booth, Anthony J
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124789 , vital:35697 , https://doi.10.1111/j.1749-7345.2004.tb00102.x
- Description: Ningu Lubeo victorianus is the only labeine fish within Lake Victoria and its catchment (Greenwood 1966; Reid 1985). This species, once widely distributed in the Lake Victoria basin and supporting a commercial fishery until the late 195Os, has declined due to overfishing (Cadwalladr 1965; Ogutu-Ohwayo 1990; Seehausen 1996). The L. victorianus fishery has not only collapsed but the species has also disappeared from some of its former habitats. Recent surveys in Uganda have only found two distant populations-one in the Sio River on the Uganda-Kenya border (0” I3’53”N, 34”00’30’E), and the second in the Kagera River on the Uganda-Tanzania border (0°56’28.1”S, 3 1’46’ 18”E) (Rutaisire 2003) (Fig. 1). Currently, there is growing interest to breed the fish for wild stock enhancement and culture as a food fish.
- Full Text:
- Date Issued: 2004
Integrated anaerobic/aerobic bioprocess environments and the biodegradation of complex hydrocarbon wastes
- Authors: Ehlers, George A C
- Date: 2004
- Subjects: Hydrocarbons -- Biodegradation Sewage -- Purification -- Anaerobic treatment Water -- Purification -- Biological treatment Anaerobic bacteria Aerobic bacteria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4011 , http://hdl.handle.net/10962/d1004071
- Description: An investigation of the biodegradation of complex hydrocarbon wastes, with emphasis on chlorinated aromatic compounds, in an anaerobic/aerobic bioprocess environment was made. A reactor configuration was developed consisting of linked anaerobic and aerobic reactors which served as the model for a proposed bioremediation strategy targeting subterranean soil/sediment/aquifer chlorinated phenol-contaminated environments. Here oxygen is frequently limited and sulphate is readily available, as occurs especially in marine sediment and intertidal habitats. In the anaerobic system the successful transformation and mobilization of the model contaminant, 2,4,6-trichlorophenol, was shown to rely on reductive dechlorination by a sulphate-reducing dependent dechlororespiring co-culture. This was followed in the aerobic system by degradation of the pollutant and its metabolites, 2,4-dichlorophenol, 4-chlorophenol and phenol, by immobilized white-rot fungi.The strategy was initially investigated separately in laboratory bench- and intermediate scale reactors whereafter reactors were linked to simulate the integrated biodegradation strategy. The application of the fungal reactor to treat an actual waste stream by degrading complex mixtures of hydrocarbons in a waste oil recycling effluent was also investigated. The mineralization of phenol and 2,4,6-TCP by immobilized fungal cultures was studied in pinewood chip and foam glass bead-packed trickling reactors. The reactors were operated in sequencing batch format. Removal efficiency increased over time and elevated influent phenol and TCP (800 and 85 mg.L⁻¹) concentrations were degraded by > 98 % in 24 – 30 h batch cycles. Comparable performance between the packing materials was shown. Uptake by the packing was negligible and stripping of compounds induced by aeration had a minimal effect on biodegradation efficiency. Reactor performances are discussed in relation to sequencing batch operation and nutrient requirements necessary to sustain fungal activity in inert vs. organic material packed systems. It was shown that a co-culture consisting of sulphate-reducing and dechlororespiring bacteria established in fed-batch and soil flasks, as well as pine chip-packed fluidized bed reactors. Results showed reductive dechlorination of 2,4,6-TCP to be in strict dependence on the activity of the sulphate-reducing population, sulphate and lactate concentrations. Transformation to 2,4-DCP, 4-CP and phenol was enhanced in sulphate deficient conditions. Dechlororespiring activity was found to be dependent on the fermentative activity of sulphate-reducing bacteria, and the culture was also shown to mobilize and dechlorinate TCP in soils contaminated with the pollutant. Linking the systems achieved degradation of the compound by > 99 % through fungal mineralization of metabolites produced in the dechlororespiring stage of the system. pH correction to the anaerobic reactor was found to be necessary since acidic effluent from the fungal reactor inhibited sulphate reduction and dechlorination. The fungal reactor system was evaluated at intermediate-scale using a complex waste oil recycling effluent. Substantial COD reduction (> 96 % in 48 h batch cycles) and removal of specific effluent hydrocarbon components was shown in diluted, undiluted (COD > 37 g.L⁻¹) and 2,4,6-TCP-spiked effluents. Industrial application of the fungal reactor was evaluated in a 14 m³ pilot plant operated on-site at a waste oil processing plant.
- Full Text:
- Date Issued: 2004
- Authors: Ehlers, George A C
- Date: 2004
- Subjects: Hydrocarbons -- Biodegradation Sewage -- Purification -- Anaerobic treatment Water -- Purification -- Biological treatment Anaerobic bacteria Aerobic bacteria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4011 , http://hdl.handle.net/10962/d1004071
- Description: An investigation of the biodegradation of complex hydrocarbon wastes, with emphasis on chlorinated aromatic compounds, in an anaerobic/aerobic bioprocess environment was made. A reactor configuration was developed consisting of linked anaerobic and aerobic reactors which served as the model for a proposed bioremediation strategy targeting subterranean soil/sediment/aquifer chlorinated phenol-contaminated environments. Here oxygen is frequently limited and sulphate is readily available, as occurs especially in marine sediment and intertidal habitats. In the anaerobic system the successful transformation and mobilization of the model contaminant, 2,4,6-trichlorophenol, was shown to rely on reductive dechlorination by a sulphate-reducing dependent dechlororespiring co-culture. This was followed in the aerobic system by degradation of the pollutant and its metabolites, 2,4-dichlorophenol, 4-chlorophenol and phenol, by immobilized white-rot fungi.The strategy was initially investigated separately in laboratory bench- and intermediate scale reactors whereafter reactors were linked to simulate the integrated biodegradation strategy. The application of the fungal reactor to treat an actual waste stream by degrading complex mixtures of hydrocarbons in a waste oil recycling effluent was also investigated. The mineralization of phenol and 2,4,6-TCP by immobilized fungal cultures was studied in pinewood chip and foam glass bead-packed trickling reactors. The reactors were operated in sequencing batch format. Removal efficiency increased over time and elevated influent phenol and TCP (800 and 85 mg.L⁻¹) concentrations were degraded by > 98 % in 24 – 30 h batch cycles. Comparable performance between the packing materials was shown. Uptake by the packing was negligible and stripping of compounds induced by aeration had a minimal effect on biodegradation efficiency. Reactor performances are discussed in relation to sequencing batch operation and nutrient requirements necessary to sustain fungal activity in inert vs. organic material packed systems. It was shown that a co-culture consisting of sulphate-reducing and dechlororespiring bacteria established in fed-batch and soil flasks, as well as pine chip-packed fluidized bed reactors. Results showed reductive dechlorination of 2,4,6-TCP to be in strict dependence on the activity of the sulphate-reducing population, sulphate and lactate concentrations. Transformation to 2,4-DCP, 4-CP and phenol was enhanced in sulphate deficient conditions. Dechlororespiring activity was found to be dependent on the fermentative activity of sulphate-reducing bacteria, and the culture was also shown to mobilize and dechlorinate TCP in soils contaminated with the pollutant. Linking the systems achieved degradation of the compound by > 99 % through fungal mineralization of metabolites produced in the dechlororespiring stage of the system. pH correction to the anaerobic reactor was found to be necessary since acidic effluent from the fungal reactor inhibited sulphate reduction and dechlorination. The fungal reactor system was evaluated at intermediate-scale using a complex waste oil recycling effluent. Substantial COD reduction (> 96 % in 48 h batch cycles) and removal of specific effluent hydrocarbon components was shown in diluted, undiluted (COD > 37 g.L⁻¹) and 2,4,6-TCP-spiked effluents. Industrial application of the fungal reactor was evaluated in a 14 m³ pilot plant operated on-site at a waste oil processing plant.
- Full Text:
- Date Issued: 2004