CREWS : a Component-driven, Run-time Extensible Web Service framework
- Authors: Parry, Dominic Charles
- Date: 2004
- Subjects: Component software -- Development , Computer software -- Reusability , Software reengineering , Web services
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4628 , http://hdl.handle.net/10962/d1006501 , Component software -- Development , Computer software -- Reusability , Software reengineering , Web services
- Description: There has been an increased focus in recent years on the development of re-usable software, in the form of objects and software components. This increase, together with pressures from enterprises conducting transactions on the Web to support all business interactions on all scales, has encouraged research towards the development of easily reconfigurable and highly adaptable Web services. This work investigates the ability of Component-Based Software Development (CBSD) to produce such systems, and proposes a more manageable use of CBSD methodologies. Component-Driven Software Development (CDSD) is introduced to enable better component manageability. Current Web service technologies are also examined to determine their ability to support extensible Web services, and a dynamic Web service architecture is proposed. The work also describes the development of two proof-of-concept systems, DREW Chat and Hamilton Bank. DREW Chat and Hamilton Bank are implementations of Web services that support extension dynamically and at run-time. DREW Chat is implemented on the client side, where the user is given the ability to change the client as required. Hamilton Bank is a server-side implementation, which is run-time customisable by both the user and the party offering the service. In each case, a generic architecture is produced to support dynamic Web services. These architectures are combined to produce CREWS, a Component-driven Runtime Extensible Web Service solution that enables Web services to support the ever changing needs of enterprises. A discussion of similar work is presented, identifying the strengths and weaknesses of our architecture when compared to other solutions.
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- Date Issued: 2004
Design of a performance evaluation tool for multimedia databases with special reference to Oracle
- Authors: Stakemire, Tonia
- Date: 2004
- Subjects: Oracle (Computer file) , Application software -- Evaluation , Database management -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4705 , http://hdl.handle.net/10962/d1015975
- Description: Increased production and use of multimedia data has led to the development of a more advanced Database Management System (DBMS), like an Object Relational Database Management System (ORDBMS). These advanced databases are necessitated by the complexity in structure and the functionality required by multimedia data. Unfortunately, no suitable benchmarks exist with which to test the performance of databases when handling multimedia data. This thesis describes the design of a benchmark to measure the performance of basic functionality found in multimedia databases. The benchmark, called MORD (Multimedia Object Relational Databases), targets Oracle, a well known commercial Object Relational Database Management System (ORDBMS) that can handle multimedia data. Although MORD targets Oracle, it can easily be applied to other Multimedia Database Management System (MMDBMS) as a result of a design that stressed its portability, and simplicity. MORD consists of a database schema, test data, and code to simulate representative queries on multimedia databases. A number of experiments are described that validate MORD and ensure its correct design and that its objectives are met. A by-product of these experiments is an initial understanding of the performance of multimedia databases. The experiments show that with multimedia data the buffer cache should be at least large enough to hold the largest dataset, a bigger block size improves the performance, and turning off logging and caching for bulk loading improves the performance. MORD can be used to compare different ORDBMS or to assist in the configuration of a specific database.
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- Date Issued: 2004
Development of a hydantoin-hydrolysing biocatalyst for the production of optically pure amino acids using Agrobacterium tumefaciens strain RU-ORPN1
- Authors: Foster, Ingrid Margaret
- Date: 2004
- Subjects: Agrobacterium tumefaciens Amino acids Hydantoin Hydrolysis Enzymes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3943 , http://hdl.handle.net/10962/d1004002
- Description: A calcium alginate bead-immobilised biocatalyst was developed utilising the D-hydantoinase and D-N-carbamoylase from a novel, mutant Agrobacterium tumefaciens strain RU-ORPN1. The growth conditions for the inducer-independent strain were optimised for production of hydantoinase and N-carbamoylase activities. Methods for the preparation of crude enzyme extracts were evaluated in terms of hydantoinase and N-carbamoylase activities produced. After comparison of the enzyme activities and stabilities in various extracts from fresh and frozen cells, sonication of frozen cells for 5 minutes was found to be the best method for the production of the enzyme extract. The optimal pH and temperature for the hydantoinase activity were pH 10 and 30°C, respectively, while pH 9 and 40°C were optimal for Ncarbamoylase activity. The hydantoinase activity was enhanced by the addition of Mg^(2+) ions to the enzyme extract and the N-carbamoylase was enhanced by the addition of Mg^(2+), Mn^(2+) or Zn^(2+) ions to the enzyme extract. The enzyme activities increased in the presence of ATP suggesting that the enzymes may be ATP-dependent. The addition of DTT and PMSF to the enzyme extract enhanced the hydantoinase activity but had no effect on the N-carbamoylase activity. The N-carbamoylase was unstable at 40°C and was almost completely inactivated after 24 hours incubation at this temperature. The hydantoinase and N-carbamoylase appeared to be insoluble. Various techniques were investigated for the solubilisation of the enzymes including various cell lysis methods, cell lysis at extremes of pH and ionic strength, addition of a reducing agent and protease inhibitors, and treatment with hydrolysing enzymes and detergents. Treatment with Triton X-100 was most effective for the solubilisation of the enzymes indicating that the enzymes were membrane-bound. Hydropathy and transmembrane prediction plots of the predicted amino acid sequences for two identified N-carbamoylase genes from A. tumefaciens RU-ORPN1 revealed possible transmembrane regions in the amino acid sequences, and thus supported the hypothesis that the enzymes were membrane-bound. Various methods were evaluated for the immobilisation of the enzymes in whole cells and enzyme extracts. Immobilisation of the enzyme extract in calcium alginate beads was found to be the best method in terms of enzyme activity retention and stability. The hydantoinase retained 55% activity while the N-carbamoylase exhibited a remarkable sevenfold increase in activity after immobilisation by this method. Furthermore, the hydantoinase activity increased after storage at 4°C for 21 days, while the N-carbamoylase retained 30% activity after this storage period. The calcium alginate bead-immobilised enzymes were further biochemically characterised and then applied in a bioreactor system for the production of D-hydroxyphenylglycine (D-HPG) from D,L-5-hydroxyphenylhydantoin (D,L-5-HPH). The pH and temperature optima for the immobilised hydantoinase were pH 7 and 50°C, respectively, while pH 8 and 40°C were optimal for the immobilised N-carbamoylase enzyme. The immobilised enzymes showed improved thermostability at 40°C in comparison to the free enzymes and retained high levels of activity after five repeated batch reactions. Low levels of conversion were obtained in a packed-bed bioreactor containing the A. tumefaciens RU-ORPN1 biocatalyst due to the low hydantoinase activity present in the strain, relative to N-carbamoylase. A novel, packed-bed bioreactor system was therefore developed for the production of D-HPG from D,L-5-HPH using the A. tumefaciens biocatalyst in combination with a Pseudomonas sp. biocatalyst having high hydantoinase activity. A conversion yield of 22 to 30% was achieved for the production of D-HPG from D,L-5-HPH over 5 days operation demonstrating that the hydantoin-hydrolysing enzymes from A. tumefaciens RU-ORPN1 could be stabilised by immobilisation and, in combination with a biocatalyst with high hydantoinase activity, could be applied to the fully enzymatic conversion of D,L-5-HPH to D-HPG.
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- Date Issued: 2004
DRUBIS : a distributed face-identification experimentation framework - design, implementation and performance issues
- Authors: Ndlangisa, Mboneli
- Date: 2004
- Subjects: Principal components analysis , Human face recognition (Computer science) , Image processing , Biometric identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4704 , http://hdl.handle.net/10962/d1015768
- Description: We report on the design, implementation and performance issues of the DRUBIS (Distributed Rhodes University Biometric Identification System) experimentation framework. The Principal Component Analysis (PCA) face-recognition approach is used as a case study. DRUBIS is a flexible experimentation framework, distributed over a number of modules that are easily pluggable and swappable, allowing for the easy construction of prototype systems. Web services are the logical means of distributing DRUBIS components and a number of prototype applications have been implemented from this framework. Different popular PCA face-recognition related experiments were used to evaluate our experimentation framework. We extract recognition performance measures from these experiments. In particular, we use the framework for a more indepth study of the suitability of the DFFS (Difference From Face Space) metric as a means for image classification in the area of race and gender determination.
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- Date Issued: 2004
English language teaching and learning in the African preschool and educational achievement at grade 1: a case study
- Authors: Rendel, Philip Boudewijn
- Date: 2004
- Subjects: Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2360 , http://hdl.handle.net/10962/d1002643 , Education, Preschool -- South Africa -- Case studies , English language -- Study and teaching (Preschool) -- South Africa Case studies , English language -- Study and teaching (Elementary) -- South Africa -- Case studies , Children -- South Africa -- Language -- Case studies , Language acquisition -- Case studies
- Description: In 1998, seventy per cent of children in South Africa failed and had to repeat the Grade 1 year. This is the result of a number of factors, among them academic and cultural readiness for school. Many primary schools in South Africa teach through English, a language that is not the home language of the majority of learners. Despite recent legislation aimed at improving preschool facilities and teacher capacity, there has been insufficient consideration of which languages are taught and how they should be taught to children before they arrive at Grade 1. This study sets out to explore whether there is a relational link between preschool English language teaching and learning and subsequent educational achievement at Grade 1. It also sketches out possible recommendations for improving the teaching and learning of English in the sample schools. The study does not attempt to enter the debate over choice of language of teaching and learning (LoLT). In this longitudinal case study, four children from two different preschools, (one mainly isiXhosa medium and one English medium), were observed in their classroom environments over a period of four months. The following year, the same children were observed in their respective Grade 1 classrooms, all of which were English medium either entirely or to a degree. The parents of all four children were interviewed in their home environment, as were their teachers. The study found that there is a significant communication gap between preschool teachers and Grade 1 teachers. This was combined with a self-confessed need amongst some teachers for increased training in teaching through English. Low motivation and limited professional experience in some cases contributed to a preschool language-learning environment that lacked many of the factors identified as being essential for a positive learning environment in early childhood There was in addition a clear bias in many sites towards universality of ECD prinCiples with little regard for the hegemony of Western pedagogy, particularly in the area of literacy acquisition. The study concludes by suggesting some ways in which this situation could be improved in order to enable preschool children to cope better with the demands of Grade 1.
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- Date Issued: 2004
Equity in the South African legal system a critical ethnography
- Authors: Leiper, Jonathan
- Date: 2004
- Subjects: Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2355 , http://hdl.handle.net/10962/d1002637 , Court interpreting and translating -- South Africa , Language and languages -- Law and legislation -- South Africa , Translators -- Training of -- South Africa , Translators -- Legal status, laws, etc. -- South Africa , Law -- Translating -- South Africa , Law -- South Africa -- Language
- Description: This thesis focuses on the process of interpreting and the difficulties faced by interpreters in the Magistrates' Court in Grahamstown, South Africa. More particularly, the thesis seeks to establish whether the constitutional guarantee of language equity can be applied to the courts - given the numerous problems with interpreting. Respondents from different spheres of the legal profession were interviewed in order to ascertain their perspectives on the state of interpreting, problems that are encountered by interpreters and attitudes displayed by other members of the legal profession towards interpreters. The methodology used in the thesis is that of a critical ethnography. As such, the research also has a critical focus, seeking to determine the ideologies and interests of different ):articipants in the legal process. On the basis of the data collected, a number of conclusions are drawn. The first is that interpreting in South Africa is in trouble. The system of interpreting is beset by a number of different problems. This study describes four different types of problems that are faced by interpreters: linguistic problems, environmental problems, training and administrative issues, and poor status in the eyes of the other participants in the legal process. Together the cumulative effect of these problems is the undermining of the principle of equity in the justice system. Finally, the thesis provides various practical and achievable solutions to the problems outlined above, specifically those faced by interpreters. The researcher also critically evaluates the efforts and motives of the Department of Justice and Constitutional Development.
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- Date Issued: 2004
Examining the feasibility of introducing environmental surcharges to finance local coastal management initiatives in South Africa : a case study in Plettenberg Bay
- Authors: Mollatt, David G R
- Date: 2004
- Subjects: Marine resources -- South Africa Marine resources conservation -- South Africa Coastal zone management -- South Africa Marine parks and reserves -- Management--South Africa Tourism--South Africa -- Taxation Tourism -- South Africa -- Economic aspects
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:999 , http://hdl.handle.net/10962/d1002734
- Description: The management of coastal resources in South Africa has come under review as a result of the degradation of environmental resources along the coast. The challenge being faced by resource managers is to achieve economic growth while sustaining South Africa’s coastal resource base (Nobel, 2000). The South African government (RSA, 2000) has developed a coastal management strategy to meet this challenge: The strategy involves the inclusion of all stakeholders in the formation of policy regarding the management of coastal resources, in a more integrated approach to coastal management. To effectively achieve this stakeholder inclusion, it has become necessary to decentralize the political, administrative and fiscal authority to conduct coastal management functions. With regard to the need for fiscal decentralisation this thesis considers the possibility of implementing localised environmental surcharges to finance coastal management initiatives. The ability of the White Paper for Sustainable Coastal Development (RSA, 2000) to provide theformal institutional structure necessary for the introduction of environmental surcharges is firstconsidered. It is shown that the decentralised management strategy has the potential to create a management style that is transparent and accountability orientated. In addition to this the style is capable of adapting to dynamic local coastal conditions and is therefore an appropriate direction in which to steer coastal management in South Africa. The effectiveness of coastal co-management as an informal institutional arrangement is then examined. Provided that local Coastal Management Fora are created to include all relevant stakeholders and that a source of long term financing is secured co-management has the potential to create the conditions necessary for effective coastal management. With regard to a source of long term financing, local environmental surcharges to finance coastal management initiatives are considered. The public’s willingness to contribute to such a surcharge is analysed in the context of Plettenberg Bay by probing their willingness to pay (WTP) for a Bay Management Plan. A survey instrument is developed to measure the public’s WTP. The design of the instrument is based on the Contingent Valuation (CV) method that is used to analyse the nonmarket benefits that environmental resources (such as Plettenberg Bay) provide the public. It is found that the resident population is willing to pay R15 per month toward a Bay Management Plan whilst domestic and foreign tourists respectively are willing to pay R6 and R22 daily. The aggregation of these WTP estimates yields a total passive use value of between R15 397 900 – R20330 500 annually. This nuclear value of the Bay should be included in the formation of local coastal management policy and provides guidance for the introduction of a local environmental surcharge. A budget for a Bay Management Plan is proposed and a progressive surcharge based on municipal property value is set. To finance the local residents’ share of the budget, a monthly surcharge of R1 would be required of the average valued property. To calculate the domestic and foreign tourist contribution to the budget a schedule of accommodation offering property will be required. However, to finance the entire budget a residential surcharge of approximately R10 would be required of the average valued property. This figure is well below the average resident population WTP of R15, highlighting the fact that an environmental surcharge in Plettenberg Bay is indeed feasible. The difference in reported WTP and the contribution required to finance the Bay Management Plan also highlights that there is scope for experimentation in the introduction of such a surcharge.
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- Date Issued: 2004
Exploring health literacy assessment : the relexicalisation of a health literacy test from the U.S. for application in a South African population
- Authors: La Rose, Christopher Michael
- Date: 2004
- Subjects: Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2373 , http://hdl.handle.net/10962/d1005708 , Rapid Estimate of Adult Literacy in Medicine , Educational tests and measurements , Literacy -- South Africa--Evaluation , Health education -- South Africa -- Evaluation
- Description: The Rapid Estimate of Adult Literacy in Medicine (REALM) is a standardised health literacy test developed in the United States that has been previously administered and researched in South Africa (Lecoko, 2000). It is an objective vocabulary test which uses item recognition of 66 health-related words where recognition is measured by pronunciation. It is designed as a screening instrument to identifY the health literacy levels of patients in clinics. Lecoko (2000) found the REALM to be largely inapplicable in a South African setting, in that only eight out of the 66 words could be deemed acceptable, in that they could be either both adequately pronounced and adequately comprehended or both inadequately pronounced and inadequately comprehended. This may have occurred for a number of reasons, including the administration of the test in a population for whom English is a second or other language, and inaccurate measurement of pronunciation and comprehension of words, with a key problem being that the choice of words in the original REALM may not accurately represent the range of conditions and issues in a South African healthcare setting. This thesis was therefore premised on the principled relexicalisation of the REALM, that replacement of the words used in the test, using a sample gathered from health information and promotion texts in local clinics, would improve its applicability. In this regard, an exhaustive sample was gathered and analysed and 66 new words were chosen. The test was also modified to include a more principled approach to pronunciation and comprehension issues, and to account for language proficiency differences in administering an English language test in an English second language population. This modified test, referred to as the REALM-M was administered to a group of respondents who were statistically similar to the group to whom the REALM had originally been administered, and the results were compared. It was found that relexicalisation increased the number of acceptable words on the test from eight to 38. However, researching the key discourses surrounding health literacy and comparing these with current discourses about literacy beyond the field of health care revealed that despite improved content validity over the REALM, the REALM-M lacked construct validity. This provided the opportunity to discuss the discourses of health literacy and to suggest the application of alternative paradigms in this field.
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- Date Issued: 2004
Factors affecting the invasion of Pteronia incana (Blue bush) onto hillslopes in Ngqushwa (formerly Peddie) District, Eastern Cape
- Authors: Kakembo, Vincent
- Date: 2004
- Subjects: Shrubs -- South Africa -- Eastern Cape Slopes (Physical geography) -- South Africa -- Eastern Cape Biological invasions -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4833 , http://hdl.handle.net/10962/d1005508
- Description: The factors that influence the invasion of hillslopes by the shrub Pteronia incana in the communal rangelands of Ngqushwa (formerly Peddie) district were investigated. Mgwalana, one of the catchments in the district where encroachment by the species is widespread, was chosen. The study combined field observations with image analysis based on high resolution infrared imagery. The catchment was flown and high resolution infrared images (1mx1m) were taken using a Kodak DCS420 digital, colour-infrared camera. The images were analysed using Idrisi32 and Kilimanjaro GIS versions. The ability of different vegetation indices to separate P. incana from the other cover types was investigated. Field observations of the degree of P. incana invasion in relation to, inter alia, soil surface conditions, slope angle and visible forms of erosion were made. A Digital Elevation Model (DEM) of 20m spatial resolution was used to derive terrain parameters. The presence and absence of P. incana in relation to slope gradient and aspect were determined. The combined influence of the two terrain parameters and land use on the invasion was also investigated. The Topographic Wetness Index (WI), a component of the TOPMODEL was derived from the DEM and its relationship with the spatial distribution of P. incana was explored. Soil moisture dependencies for P. incana and grass species as well as surrogates for runoff under the shrub and adjacent bare areas were determined in the field. A high level of classification accuracy confirmed the reliability of digital camera imagery for spatial analyses. Distinct spectral separability for the surface vegetation cover types was achieved by means of the Perpendicular Vegetation Index (PVI) as opposed to the ratio based vegetation indices (NDVI, SAVI and MSAVI). The absence/presence of P. incana was noted to be strongly influenced by slope angle and aspect. The probability for P. incana occurrence increased with slope steepness and southerly slope orientation. Abandoned and grazing lands were identified as the main invasion hotspots. Blanket invasion of the former signified the high susceptibility of abandoned land to P. incana invasion. The combined influence of land use, slope gradient and aspect was also noted to have promoted the invasion. This is borne out by the concentration of the invasion on abandoned steep slopes with a southerly orientation. Local topographic variations were identified as having a strong bearing on P. incana spatial distribution. The topographically driven WI confirmed this relationship, such that P. incana was associated with the low WI values of convexities. Differences in the moisture dependencies between P. incana and grass species were demonstrated by the greater rooting depth of the former. During field surveys, soil surface crusting was noted as inherent to P. incana patchiness. The coupling between local topography and soil surface crusting underpins soil moisture variability at hillslope and patch scales respectively. This in turn determines the competition between P. incana and grass species and the eventual replacement of the latter by the former. A close spatial correlation between fully established P. incana and severe forms of soil erosion was observed. Loss of patchiness and expansion of inter-patch bare areas promote runoff connectivity erosion. As most of the runoff becomes run out, hillslopes tend towards dysfunctional systems. Greater soil moisture storage after rainstorms under P. incana tussocks than the adjacent bare areas signifies the shrub’s water harvesting capabilities. The tussocks could thus serve as a starting-pointbuilding- block for the rehabilitation of dysfunctional hillslope systems.
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- Date Issued: 2004
Filling the gap : Nietzsche's account of authenticity as a supplementary ideal
- Authors: Baker, Michaela Christie
- Date: 2004
- Subjects: Nietzsche, Friedrich Wilhelm, 1844-1900 -- Ethics , Authenticity (Philosophy) , Ethics, Modern , Normativity (Ethics) , Self-knowledge, Theory of
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2727 , http://hdl.handle.net/10962/d1003734 , Nietzsche, Friedrich Wilhelm, 1844-1900 -- Ethics , Authenticity (Philosophy) , Ethics, Modern , Normativity (Ethics) , Self-knowledge, Theory of
- Description: This thesis examines the ideal of authenticity: why we might want or need such an ideal, what such an ideal would look like, and what mechanisms we would need to ensure the successful operation of such an ideal. The thesis has three main parts. The first part of the thesis aims at motivating the need to look to authenticity as a supplementary ideal to normative moral theory. I do this by drawing a distinction between ethics and morality and arguing that there are important aspects of our lives (such as our relations to ourselves) our beliefs and projects) about which normative moral theory fails to give us guidance and about which an ethical ideal, namely that of authenticity, can provide us with the requisite guidance. The second part of the thesis elucidates Nietzsche's view of authenticity as eternal return. I argue that eternal return consists in holding a particular attitude to one's life - one's past, present and future. I then demonstrate that what is fundamental to successfully living authentically in accordance with eternal return is a rigorous search for self-knowledge. In the third part of the thesis I argue that, in order to achieve the self-knowledge necessary to being a successful authentic agent, one must acquire it through a process of dialogue with other agents. I give a model of self-knowledge as a dialogic encounter that provides two important mechanisms whereby such self-knowledge can be gained.
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- Date Issued: 2004
Fishes in the Mngazi and Mngazana estuaries, with particular emphasis on the community structure and primary carbon sources
- Authors: Mbande, Sekiwe
- Date: 2004
- Subjects: Fishes -- South Africa -- Mngazi Estuary , Fishes -- South Africa -- Mngazana Estuary , Fishes -- Effect of habitat modification on -- South Africa -- Mngazi Estuary , Fishes -- Effect of habitat modification on -- South Africa -- Mngazana Estuary , Estuarine fishes -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishes -- Physiology , Fishes -- Effect of water quality on , Fishes -- Effect of temperature on , Fishes -- Food , Fishes -- Effect of turbidity on
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5700 , http://hdl.handle.net/10962/d1005386 , Fishes -- South Africa -- Mngazi Estuary , Fishes -- South Africa -- Mngazana Estuary , Fishes -- Effect of habitat modification on -- South Africa -- Mngazi Estuary , Fishes -- Effect of habitat modification on -- South Africa -- Mngazana Estuary , Estuarine fishes -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape , Fishes -- Physiology , Fishes -- Effect of water quality on , Fishes -- Effect of temperature on , Fishes -- Food , Fishes -- Effect of turbidity on
- Description: The fish community structure of two contrasting estuaries, one with a well developed mangrove forest (Mngazana) and the other without mangroves (Mngazi) was compared. Both the Mngazi and Mngazana estuary fish communities were dominated by marine species, reflecting the importance of these systems as nursery areas for marine fishes. The Mngazi Estuary contained 18% more estuarine fishes in terms of catch per unit effort (CPUE) than the Mngazana Estuary. The reduced tidal influence due to the narrow mouth opening is a possible reason for the heightened CPUE of estuarine species in the Mngazi estuary. The recorded higher diversity of fish species in the Mngazana Estuary when compared with the Mngazi Estuary was attributed to the greater influence of the marine environment due to the wide permanently open mouth, as well as the presence of a variety of habitats in this system. In both estuaries tropical and temperate species were captured, confirming the transitional nature of their biogeographic location which is situated close to the boundary between the subtropical and warm temperate regions of the Southern African coastline. Contrary to previous studies, which recorded seasonal changes in the proportions of tropical and temperate species, the proportions of tropical species remained unchanged at approximately 70% during the January and June sampling occasions. Global warming as a possible reason for the increased dominance of tropical species is discussed. Although several studies in southern Africa have investigated estuarine food web structure, none have compared mangrove and non-mangrove estuaries. In this study, the primary sources of carbon utilised by the fish fauna in the Mngazi and Mngazana estuaries was investigated. The carbon isotopic values of fishes in both estuaries displayed a continuum rather than a tight clustering around particular energy sources. Most detritus feeders of the family Mugilidae (mullets) from both estuaries were relatively more enriched than other fish taxa. The isotopic values of the mullet species suggest a diet derived from relatively enriched carbon sources such as benthic microalgae, the eelgrass Zostera capensis and associated epiphytes. Based on the isotopic values, piscivorous fishes from both estuaries could not be linked to specific prey fish taxa, but clearly the mullet species were not their main food source. The invertebrate feeders that were found in both estuaries showed greater isotopic variations in the Mngazana Estuary than in the Mngazi Estuary, probably reflecting the higher diversity of habitats (carbon sources) and invertebrate prey species in the Mngazana system. Generally the isotopic signatures of fishes from the Mngazi Estuary were more enriched than those from the Mngazana Estuary, thus indicating the possible effect of δ¹³C depleted mangrove derived carbon in the latter system.
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- Date Issued: 2004
Framing the other : representations of Africa in The Japan Times/Online between January and December 2000 : a case study
- Authors: Ngoro, Blackman Rodrick
- Date: 2004
- Subjects: Africa -- In mass media -- Japan , Newspapers -- Japan , Japan Times/Online , Africa -- Foreign public opinion, Japanese
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3476 , http://hdl.handle.net/10962/d1002931 , Africa -- In mass media -- Japan , Newspapers -- Japan , Japan Times/Online , Africa -- Foreign public opinion, Japanese
- Description: The aim of this study is to find out, against the news genre norms, how representations of particular regions are produced in the structure of newspaper reporting in the foreign news sub-genre. The study focuses on news reports concerning Africa, or African countries, in one Tokyo-based newspaper: The Japan Times/Online. The study is theoretically informed by Cultural Studies – a field of study concerned with the study of ideology and power in discourse – and investigates how Africa and African countries are represented as “other” than developed countries. This is a textual study that focuses on the production moment using Critical Discourse Analysis methods. Critical discourse analysis is interested in the study of ideological forms that have become naturalised over time, so that ideology has become common sense. The first part of the study analyses headlines and reveals evidence of ideological positions adopted by The Japan Times/Online in the representation of, firstly, home or Japanese actors, which is very different to the representation of African actors. The second part of the analysis examines the structures of the texts and the language used therein. The evidence from this analysis shows how Africa is represented as a Third World entity through various crises, including a health epidemic, perceptions of political instability and economic instability, an inadequate business image, as well as market and managerial skills, and wars and conflict. The study concludes with a discussion of the representation of Africa and African countries as a part of the Third World entity. This representation reflects and naturalises social inequality between developed countries and those of the Third World, of which Africa is a part. The representation of Africa as a Third World entity also naturalises the social, health, economic and political conditions said to be characteristic of African countries. It is this process of representation that reveals the power relations between Japan as a First World country and Africa as part of the Third World.
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- Date Issued: 2004
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.
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- Date Issued: 2004
Geographic susceptibility of Helicoverpa armigera (Lepidoptera: Noctuidae) to insecticidal proteins in Bt-cotton in South Africa
- 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.
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- 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
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- 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.
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- 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.
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- 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.
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- 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.
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- 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.
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- Date Issued: 2004