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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

The evaluation of ozone technology to reduce the concentration of polychlorinated biphenyls (PCBs) in contaminated soil.

Moodley, Shanita Jeewan. January 2011 (has links)
Polychlorinated Biphenyls (PCBs) are hazardous and toxic chemicals to both humans and animals. In the late 1960’s PCBs were discovered to be a harmful pollutant which could cause environmental contamination due to its slow degradation and even trace amounts of PCBs were regarded as toxic to both human and animals. Oil spills are a frequent occurrence at Eskom substations which could contain PCBs. The contaminated sediments which are easily carried away by rain and wind can further contaminate the environment and aquatic bodies. Eskom currently disposes of soil and ballast stones contaminated with PCBs by thermal destruction. This is a costly process as PCBs are regarded as hazardous materials and needs to be safely transported and disposed of at a licensed disposal facility. Based on literature, ozone has been used on a laboratory scale to treat soil contaminated with PCBs with the addition of chemicals such as hexane and acetone which assist in breaking down PCBs. The objective of this study was to evaluate whether ozone without the addition of chemicals could reduce the levels of PCBs present in contaminated soil. In this study, two soil samples and one ballast stone sample were contaminated with 50 ppm, 200 ppm and 600 ppm of PCBs and then exposed to 0.4, 0.5 and 0.6 l/min of ozone for a period of 60 minutes to examine the effects of increasing ozone flow rates on PCB destruction in soil. The results of the experimental tests showed that ozone gas reduced the concentration of PCBs in the soil and ballast stone samples for the different total gas flow rates. The literature study identified that the final products of the ozonation of PCBs are carbon dioxide and water and that any products formed after this process could possibly be degraded by the soil natural microorganisms. Calculations based on the Shin et al. (2004) model proved that ozone was in excess after the ozonation process. The results of the experiments also confirmed this, as the PCB residuals were similar for all three total gas flows, which showed that there was no dependence on the gas flow rates hence, ozone was in excess. The experimental data was then trended with zero, first and second order reaction equations, which showed that the best fit was obtained with the firstorder reaction equation. It is recommended that ozone be used for the treatment of PCB contaminated soil at Eskom substations. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2011.
212

Pilot study investigating the effectiveness of cognitive rehabilitation therapy with patients with schizophrenia with a forensic history

Dodds, Julie January 2009 (has links)
Objectives: To evaluate the effectiveness of cognitive rehabilitation therapy with patients with schizophrenia within a forensic population. The intervention aimed to improve domains of cognitive functioning which have been found to be impaired as a result of schizophrenia. Forensic patients with schizophrenia have been found to have greater impairments in cognitive functioning relative to non-violent patients. Therefore interventions which target these deficits are important in rehabilitation interventions. Design: A within subject repeated design was used. A control measure was also implemented which involved patients being used as their own control. Method: 17 participants successfully completed the cognitive rehabilitation intervention. Initially 23 participants were recruited. Participants received approximately five hours of the computer-assisted cognitive remediation administered over seven weekly sessions. Outcome measures were cognitive assessments measuring executive functioning, attention, verbal learning and memory, perceptual organisation and visual memory. Outcome measures were administered pre-intervention, during treatment, post treatment and at three months follow up. A control assessment was also administered prior to the commencement of the intervention. Results: Post treatment measures on attention, perceptual organisation, visual memory and aspects of executive functioning were found to be significantly improved in comparison to pre intervention and control assessments. At 3 month follow up these improvements in cognitive functioning were found to be sustained. Conclusion: The pilot study indicated that cognitive rehabilitations are effective in improving cognitive functioning within forensic populations with schizophrenia. These results have the potential to improve functional outcomes and recovery, which could indirectly improve symptoms and risk of future violence. Further research is required in this area to provide additional evidence for this intervention to be available to forensic patients with schizophrenia.
213

Towards a novel methodology for the environmental remediation of oil-polluted aqueous systems

Lawson, Jeffrey January 2010 (has links)
Aromatic hydrocarbons are a prevalent constituent of crude oil. The refined products of crude oil such as petroleum and diesel can find their way into groundwater though oil-spillages and are also present in the oil and gas industry’s produced water. These aromatics are biorecalcitrant, however upon ingestion with water, may be metabolised to toxic intermediates that are carcinogenic or mutagenic in nature. Although some treatment technologies are available most of these are under development and are yet to be proven in the field. This illustrates the need for novel, economical and environmentally friendly technologies to be developed with a view to remediating aqueous systems that have been polluted with aromatics hydrocarbons. The supramolecular cyclodextrin molecule, with its hydrophobic interior and hydrophobic exterior seems to be an excellent molecule for the trapping of the pollutant molecules, however the inclusion complexes with this cyclic sugar are water-soluble therefore there is a need for the cyclodextrin to be rendered waterinsoluble. A study of the aqueous solubilities of some aromatic hydrocarbons that may be present in crude oil has been carried out and shows that the majority of these molecules have a degree of water solubility that may increase upon environmental weathering. The successful reaction between a solid-phase resin and the β-cyclodextrin molecule has been achieved, with the total dryness of the system being required including Soxhlet extraction of the resin with anhydrous acetone before the reaction. The reaction between β-cyclodextrin and a range of isocyanates proved unsuccessful, but a range of symmetrical aryl ureas were synthesised from their isocyanates with the influence that different activating or deactivating groups on the ring have on the propensity to form the ureas being shown. The successful alkylation between β-cyclodextrin and a series of haloalkanes has shown the effect of increasing chain length on the degree of alkylation. This reaction involved the deprotonation of the cyclodextrin by sodium hydride in anhydrous dimethyl sulphoxide followed by reaction with the alkyl iodide. Increasing the equivalents of hydride or iodide, or the reaction time did not have a noticeable effect on the degree of reaction indicating that steric constraints were limiting the degree of reaction. Testing several of these alkyl iodides gave an indication as to their tendency to uptake and remove several model pollutants that had been dissolved in water with the propylated β-cyclodextrin displaying potential for the remediation of aqueous systems that had been polluted. Several of these results were very promising leading to the conclusion that further derivatives of these alkylated sugars may be even more suitable for future research into the remediation of organically polluted aqueous systems.
214

The photographer as environmental activist : politics, ethics and beauty in the struggle for environmental remediation

Scott, Conohar January 2015 (has links)
This practice-based research study examines two questions in an effort to determine how the photographer can play a role in the promulgation of environmental activism. Firstly, I ask if certain aesthetic approaches to the documentation of industrial pollution can be regarded as antithetical to the values of environmentalism; in particular, I examine the use of the sublime and the role that beauty plays in documenting scenes of environmental despoliation. In response to this question, I describe the problems associated with establishing a counter-aesthetic position in my artistic practice, which is commensurate with environmental ethics. Secondly, I ask how photography can be used as a means of conducting environmental protest by working in solidarity with environmental scientists and activists, in the struggle for environmental remediation. In a bid to answer this question, I argue that the production and dissemination of the photobook is one method of realising the dissensual capacity of art to bring about the conditions necessary for remediation to occur. Importantly, my practice proceeds through an understanding of debates ongoing in contemporary theory. In particular, I argue that Jacques Rancière s conceptions of dissensus (Rancière, 2010: 173) and the politics of aesthetics (Rancière, 2004: 25) can be interpreted as a means of understanding how aesthetics can be used to enact a form of political praxis. Using Rancière and Murray Bookchin s concept of social ecology as a basis for my artistic practice, I claim that photography can not only make the existent reality of pollution visible, it can also initiate a form of participatory democratic subjectivity, allowing the demands of the artist to become visible too. Moreover, in the design and dissemination of the three photobooks I have created, I make a case for a collaborative model of artistic practice, which extends beyond the medium specificity of photograph, and embraces multimodality and trans-disciplinarity, as a means of situating the photograph into a broader discursive field.
215

Designing for indeterminacy

He, Xuan 08 July 2016 (has links)
The relocation of Chongqing Iron and Steel Company (CIS) in 2011 resulted in its old site’s demolition in 2012. As one of the largest post-industrial sites in Chongqing, it faces many future challenges. Framed by an existing redevelopment plan, this practicum proposes a design that responds to the current site conditions and lays groundwork for its future. The design capitalizes on the existing attributes of the site to create a variety of experiences. It employs phytotehcnologies to remediate contaminated soil and also offers opportunities for research, education and recreation. Personal experiences and reflections on China’s post-industrial regeneration are also discussed. / October 2016
216

Estudo para utilização de vermicomposto com vistas à remediação de solos contaminados com cromo, cobre e chumbo / Study for use of vermicompost with a view to remediation of soils contaminated with chromium, copper and lead

Mendes, Leandro Antunes 11 October 2012 (has links)
As atividades industriais e de mineração, juntamente com o uso inadequado de fertilizantes e pesticidas, tem contribuído para o aumento da contaminação do solo, cursos d\'água e lençol freático por elementos tóxicos. A procura pelo desenvolvimento de soluções tecnológicas tem aumentado para atender à legislação ambiental. Segundo a ABETRE, no Brasil, apenas 22% dos 2,9 milhões de toneladas de resíduos industriais perigosos produzidos nas últimas décadas recebem tratamento adequado, sendo os 78% restantes colocados indevidamente em lixões sem tratamento prévio. Vários métodos de remediação de solos contaminados são conhecidos, entre eles estão o isolamento, imobilização, redução da toxicidade, separação física e extração. Neste contexto, destaca-se a vermicompostagem que utiliza as minhocas para degradar a matéria orgânica recente, tonando-a um material quimicamente mais estabilizado, além de remover os elementos tóxicos do solo acumulando-os em seu organismo. Dentre outros benefícios dessa técnica, destacam-se a manutenção da fertilidade do solo e a grande aceitação pública por ser uma tecnologia verde. Este trabalho tem como objetivo determinar a relação entre as concentrações de elementos tóxicos (Cr, Cu e Pb) com o vermicomposto. É avaliada a adição do material adsorvente aos solos com o intuito de conhecer a capacidade de retenção deste material para posterior descontaminação de solos contaminados. Propriedades químicas, como: pH, teor de matéria orgânica, capacidade de troca catiônica, carbono orgânico total, e físicas: umidade e granulometria são estudadas. Conclui-se com este trabalho que o vermicomposto mostrou-se um excelente material adsorvente para as espécies metálicas estudadas, sendo a ordem de adsorção Pb2+ < Cu2+ < Cr3+. / Industrial and mining activities, as well as the inappropriate use of fertilizers and pesticides, have been contributing to the increase of the contamination of soils, watercourses and water tables by toxic elements. The search for the development of technological solutions has grown to comply with the environment legislation. According to ABETRE, only 22% of 2.9 million of tones of dangerous industrial residues, produced in Brazil, received an appropriate treatment in recent decades. The remaining 78% are thrown in dumps without previous treatment. Many methods of contaminated soil remediation are known, among them isolation, immobilization, toxicity reduction, physical separation and extraction. In this context, it stands out vermicomposting that uses worms to degrade the recent organic matter, which becomes a more chemically stabilized material, and this practice also removes accumulated toxic elements from soil. Among others benefits of this practice there are soil fertility maintenance and the acceptance of people as it is a green technology. This work aims at determining the relation between the concentration of toxic elements (Cr, Cu e Pb) and the vermicompost. The addition of the adsorptive material to soil is assessed by determining the retention capacity of this material for a later decontamination of soils. Both chemical (pH, organic matter content, cationic change capacity and total organic carbon) and physical properties (humidity and granulometry) have been studied. In this study, it was concluded that vermicompost proved to be an excellent adsorbent material to the studied metallic species, and the adsorption order was Pb2+ < Cu2+ < Cr3+.
217

Recuperação de áreas contaminadas: um novo desafio para projetos paisagísticos / Recuperation of contaminated sites: a new challenge to landscape design

Morinaga, Carlos Minoru 28 March 2007 (has links)
Resultado da realização de determinadas atividades, como indústrias, depósitos, disposição de resíduos, a contaminação do solo e das águas subterrâneas é um tema que só num passado muito recente ganhou certa evidência, em razão dos efeitos danosos ao meio ambiente e à saúde em geral e da descoberta e divulgação de casos que se tornaram emblemáticos. Na cidade de São Paulo, a reutilização de locais com tais características tem ocorrido muitas vezes de modo impróprio, num contexto de mudanças de uso do solo em função da alteração do perfil econômico da cidade. A existência dessas áreas contribui efetivamente para a deterioração do espaço urbano, com conseqüências imediatas na paisagem. A contaminação, no entanto, não significa a inviabilização da utilização de uma área, desde que procedimentos adequados sejam adotados, o que pode representar uma oportunidade para a requalificação de importantes regiões da cidade. Dessa forma, o objeto deste trabalho compreende o estudo das potencialidades e das limitações apresentadas na formulação, implantação e monitoramento de projetos paisagísticos em áreas contaminadas na cidade de São Paulo. / Result of the performing of certain activities, such as industries, warehouses, waste disposal, the soil and groundwater contamination is a theme which has gained certain prominence in a very recent past, due to the damaging effects to the environment and the health in general as well to the discovery and revealing of cases that became emblematic. In the city of São Paulo, the reuse of places with such characteristics has frequently occurred in an inappropriate way, within a context of change of the land use as a result of the modification in the economical characteristics of the city. The existence of those areas contributes effectively to the deterioration of the urban space with immediate consequences to the landscape. The contamination, however, doesn?t mean the unfeasibility of the reuse of an area, since the right procedures are adopted, which may represent an opportunity of requalification of important regions of the city. Thus, the object of this work deals with the study of the potentialities and the limitations presented in the formulation, implementation and monitoring of landscape designs in contaminated sites in the city of São Paulo.
218

A remediação fonológica como facilitadora na apropriação da leitura e da escrita por crianças de salas de recursos multifuncionais / Phonological remediation as a facilitator in the appropriation of reading and writing by children from multifunctional resource classrooms

Lima, Edson Alexandre de 22 November 2017 (has links)
Estudos a respeito das dificuldades de aprendizagem tem se tornado o foco de pesquisas nacionais e internacionais. Destacam-se, principalmente, aqueles que priorizam os aspectos da intervenção, pois são notáveis os progressos acadêmicos, emocionais e sociais dos indivíduos com dificuldades de leitura e escrita. Com relação às dificuldades de aprendizagem e as dificuldades escolares, a literatura revela a necessidade da identificação precoce e propõe programas de remediação fonológica que têm como objetivo treinar as habilidades metalinguísticas e o ensino da relação letra-som, necessários para a aprendizagem do sistema de escrita. Alguns autores propõem intervenções por meio de treino computadorizado, outros autores, além do treino, propõem a associação do mesmo a atividades de leitura e escrita. Considerando o exposto, o objetivo deste estudo foi verificar os efeitos de um programa de remediação fonológica, associado a atividades de leitura e escrita, dentro do processo de alfabetização e letramento em alunos com dificuldades de aprendizagem, que frequentam uma sala de recursos multifuncionais. Foram selecionados 10 alunos na faixa etária entre 7 e 11 anos de idade, de ambos os gêneros, com dificuldades de aprendizagem, participantes de uma sala de recursos multifuncionais. Os participantes foram divididos em 2 grupos: Grupo Experimental (6 alunos) e Grupo Comparativo (4 alunos). O GE foi submetido ao programa de remediação fonológica a fim de comparar os resultados da aplicação do programa aos alunos do GC, que inicialmente não receberam a intervenção. Foram realizadas avaliação pré e pós ao programa a fim de verificar o desempenho dos participantes nas habilidades do processamento fonológico, leitura e escrita, memória auditiva e visual. Os atendimentos foram em grupos de 3 alunos, realizados uma vez por semana, com duração de 50 minutos. Os resultados revelaram que o desempenho do grupo submetido ao programa foi superior ao do grupo não submetido. Observou-se que a remediação fonológica, associada a atividades de leitura e escrita, promoveu melhoras nas habilidades de leitura e escrita em alunos com dificuldades de aprendizagem das salas de recursos multifuncionais. / Studies on learning difficulties have become the focus of national and international research. Of particular note are those who prioritize aspects of the intervention, since the academic, emotional and social progress of individuals with reading and writing difficulties is remarkable. With regard to learning difficulties and school difficulties, the literature reveals the need for early identification and proposes phonological remediation programs that aim to train the metalinguistic abilities and the teaching of the letter-sound relationship, necessary for the learning of the writing system. Some authors propose interventions through computerized training, other authors, besides the training, propose the association of the same to activities of reading and writing. Considering the above, the objective of this study was to verify the effects of a phonological remediation program, associated to reading and writing activities, within the process of literacy in students with learning disabilities, attending a multifunctional resource classroom. We selected 10 students aged 7 to 11 years of age, of both genders, with learning difficulties, participants of a multifunctional resource room. Participants were divided into 2 groups: Experimental Group (6 students) and Comparative Group (4 students). The EG was submitted to the phonological remediation program in order to compare the results of the application of the program to CG students, who did not initially receive the intervention. Pre and post evaluation of the program were carried out to verify the performance of participants in the phonological processing, reading and writing skills, auditory and visual memory. The visits were in groups of 3 students, held once a week, lasting 50 minutes. The results showed that the performance of the group submitted to the program was superior to that of the group not submitted. It was observed that phonological remediation, associated with reading and writing activities, promoted improvements in reading and writing skills in students with learning difficulties in multifunctional resource rooms.
219

A study on the pollutant pentachlorophenol-degradative genes and enzymes of oyster mushroom Pleurotus pulmonarius.

January 2002 (has links)
by Wang Pui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 115-128). / Abstracts in English and Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / List of Figures --- p.vi / List of Tables --- p.viii / Abbreviations --- p.ix / Chapter 1. --- Introduction Pg no / Chapter 1.1 --- Ligninolytic enzyme systems --- p.1 / Chapter 1.2 --- Three main ligninolytic enzymes --- p.3 / Chapter 1.2.1 --- Lignin peroxidases (LiP) --- p.3 / Chapter 1.2.2 --- Gene structure and Amino acid sequence structure --- p.7 / Chapter 1.2.3 --- Regulation of expression --- p.8 / Chapter 1.3. --- MnP --- p.8 / Chapter 1.3.1 --- General properties --- p.8 / Chapter 1.3.2 --- Gene structure and Amino acid sequence --- p.9 / Chapter 1.3.3 --- Regulation of Expression --- p.12 / Chapter 1.4 --- Laccase --- p.12 / Chapter 1.4.1 --- General Properties --- p.12 / Chapter 1.4.2 --- Gene structure and Amino acid sequence --- p.14 / Chapter 1.5 --- Pentachlorophenol (PCP) --- p.16 / Chapter 1.5.1 --- Production --- p.16 / Chapter 1.5.2 --- Toxicity --- p.15 / Chapter 1.5.3 --- Persistence --- p.19 / Chapter 1.6 --- Oyster mushroom --- p.22 / Chapter 1.7 --- Application of ligninolytic enzymes in bioremediation --- p.23 / Chapter 1.7.1 --- Genetic modification --- p.23 / Chapter 1.7.2 --- Characterization of enzymes properties --- p.25 / Chapter 1.7.3 --- Ligninolytic enzymes Purification and extraction --- p.26 / Chapter 1.7.4 --- Immobilization of ligninolytic enzymes --- p.26 / Chapter 1.8 --- Fermentation --- p.29 / Chapter 1.8.1 --- Different types of fermentation --- p.29 / Chapter 1.8.1.1 --- Submerged fermentation (SF) --- p.29 / Chapter 1.8.1.2 --- Solid State Fermentation (SSF) --- p.30 / Chapter 1.9 --- Proposal and experimental plan of the project --- p.33 / Chapter 1.9.1 --- Objectives --- p.34 / Chapter 2. --- Methods --- p.36 / Chapter 2.1 --- Materials / Chapter 2.1.1 --- Culture maintenance --- p.36 / Chapter 2.1.2 --- Preparation of Pentachlorophenol (PCP) stock solution --- p.36 / Chapter 2.2 --- Optimization of production of ligninolytic enzymes by effective PCP concentration --- p.37 / Chapter 2.2.1 --- Preparation of mycelial homogenate --- p.37 / Chapter 2.2.2 --- Incubation --- p.37 / Chapter 2.2.3 --- Specific enzyme assays --- p.38 / Chapter 2.2.3.1 --- Laccase --- p.38 / Chapter 2.2.3.2 --- Manganese peroxidase (MnP) --- p.39 / Chapter 2.2.3.3 --- Lignin peroxidase (LiP) --- p.39 / Chapter 2.2.3.4 --- Protein --- p.39 / Chapter 2.3 --- Cloning of specific PCP-degradative laccase cDNA --- p.40 / Chapter 2.3.1 --- Isolation of total RNA --- p.41 / Chapter 2.3.2 --- Spectrophotometric quantification and qualification of DNA and RNA --- p.41 / Chapter 2.3.3 --- First strand cDNA synthesis --- p.42 / Chapter 2.3.4 --- Amplification of laccase cDNA --- p.43 / Chapter 2.3.4.1 --- Design of primers for PCR reaction --- p.43 / Chapter 2.3.4.2 --- Polymerase chain reaction --- p.44 / Chapter 2.3.5 --- Agarose gel electrophoresis of DNA --- p.44 / Chapter 2.3.6 --- Purification of PCR products --- p.45 / Chapter 2.3.7 --- TA cloning of PCR products --- p.46 / Chapter 2.3.8 --- Preparation of Escherichia coli competent cells --- p.46 / Chapter 2.3.9 --- Bacterial transformation by heat shock --- p.47 / Chapter 2.3.10 --- Colony screening --- p.48 / Chapter 2.3.11 --- Mini-preparation of plasmid DNA --- p.48 / Chapter 2.3.12 --- Sequencing --- p.49 / Chapter 2.3.13 --- Identification of sequence --- p.51 / Chapter 2.4 --- Study of regulation temporal expression of laccase genes by PCP --- p.51 / Chapter 2.4.1 --- Semi-quantitative PCR --- p.51 / Chapter 2.4.1.1 --- Design of gene-specific primers --- p.51 / Chapter 2.4.1.2 --- Determination of suitable PCR cycles --- p.54 / Chapter 2.4.1.3 --- Normalization of the amount of RNA of each sample --- p.54 / Chapter 2.5 --- Quantification of residual PCP concentration --- p.55 / Chapter 2.5.1 --- Extraction of PCP --- p.55 / Chapter 2.5.2 --- High performance liquid chromatography --- p.55 / Chapter 2.5.3 --- Assessment criteria --- p.56 / Chapter 2.6 --- Effect of other componds on laccase activity and laccase expression --- p.56 / Chapter 2.6.1 --- Study of different isoform of laccase --- p.57 / Chapter 2.6.2 --- SDS-PAGE analysis of proteins --- p.58 / Chapter 2.7 --- Study of laccase expression and laccase activity in fruiting process of oyster mushroom --- p.59 / Chapter 2.8 --- Statistical analysis --- p.60 / Chapter 3. --- Results --- p.61 / Chapter 3.1 --- Production of Ligninolytic Enzymes by oyster mushroom / Chapter 3.1.1 --- Optimization of laccase production --- p.62 / Chapter 3.1.2 --- Optimization of MnP production --- p.64 / Chapter 3.1.3 --- Change of Protein content at different PCP concentration and time --- p.64 / Chapter 3.1.4 --- Change of specific activity at different PCP concentration and time --- p.64 / Chapter 3.1.5 --- Toxicity of PCP towards mycelial growth --- p.67 / Chapter 3.1.6 --- Enzyme productivities of laccase and MnP --- p.67 / Chapter 3.1.7 --- Change of % of residual PCP concentrations during 14 days --- p.70 / Chapter 3.2. --- Cloning of PCP-degradative laccase genes --- p.70 / Chapter 3.3 --- Regulation of expression of the laccase genes by PCP --- p.74 / Chapter 3.3.1 --- Determination of suitable PCR cycles --- p.74 / Chapter 3.3.2 --- Normalization of total RNA amount of different samples --- p.74 / Chapter 3.3.3 --- Regulation of temporal expression of the laccase genes by PCP --- p.74 / Chapter 3.4 --- Effect of other compounds and physiological status on laccase activity and expression --- p.81 / Chapter 3.5 --- Study of different forms of laccase --- p.86 / Chapter 4. --- Discussion --- p.93 / Chapter 4.1 --- Production of Ligninolytic enzymes by Pleurotus pulmonarius / Chapter 4.1.1 --- Optimization of laccase and MnP production by PCP --- p.95 / Chapter 4.2 --- Cloning of laccase genes --- p.97 / Chapter 4.2.1 --- Cloning strategy --- p.97 / Chapter 4.2.2 --- Analysis of Nucleotide sequence of Lac1 - Lac3 --- p.99 / Chapter 4.2.3 --- Characterization and comparison of deduced amino acid sequences of Lacl-Lac3 --- p.99 / Chapter 4.3 --- Regulation of expression of the laccase genes by PCP --- p.100 / Chapter 4.3.1 --- Regulation of temporal expression by PCP --- p.100 / Chapter 4.4 --- Effect of the potential inducers on laccase activity and expression --- p.103 / Chapter 4.5 --- Effect of the physiological status on laccase activity and expression --- p.105 / Chapter 4.5.1 --- Production of PCP-degradative laccase by Solid-state fermentation --- p.107 / Chapter 4.5.2 --- Uses of molecular probe in bioremediation --- p.107 / Chapter 4.6 --- Different isoforms of laccase --- p.109 / Chapter 4.7 --- Conclusion --- p.112 / Chapter 4.8 --- Further studies / Chapter 4.8.1 --- Confirmation of PCP-degradation by gene product of Lac1 and Lac2 --- p.114 / Chapter 4.8.2 --- Optimization of PCP-degradative laccases production by solid-state fermentation --- p.114 / Chapter 5. --- References --- p.115
220

Treatment of 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDE) by an edible fungus Pleurotus pulmonarius.

January 2006 (has links)
Chan Kam Che. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 199-219). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstracts --- p.iii / 摘要 --- p.v / Contents --- p.vii / List of figures --- p.xiv / List of tables --- p.xix / Abbreviations --- p.xxii / Chapter Chapter I --- Introduction --- p.1 / Chapter 1.1 --- Persistent organic pollutants --- p.1 / Chapter 1.2 --- DDT and DDE --- p.2 / Chapter 1.2.1 --- Background --- p.2 / Chapter 1.2.2 --- Health effects --- p.4 / Chapter 1.2.3 --- Environmental exposure of DDE --- p.4 / Chapter 1.2.4 --- Level of DDE in human --- p.9 / Chapter 1.2.5 --- Biodegradation of DDE --- p.10 / Chapter 1.3 --- Remediation methods --- p.11 / Chapter 1.3.1 --- Physical/ chemical treatment --- p.11 / Chapter 1.3.2 --- Bioremediation --- p.13 / Chapter 1.4 --- Fungal Bioremediation --- p.14 / Chapter 1.5 --- Ligninolytic enzymes --- p.15 / Chapter 1.5.1 --- Laccase --- p.15 / Chapter 1.5.2 --- Peroxidases --- p.20 / Chapter 1.5.2.1 --- Manganese Peroxidase (MnP) --- p.20 / Chapter 1.5.2.1 --- Lignin Peroxidase (LiP) --- p.24 / Chapter 1.6 --- Cultivation of Pleurotus pulmonarius --- p.27 / Chapter 1.7 --- Enzyme technology on environmental cleanup and its limitation --- p.28 / Chapter 1.8 --- Aims and objectives of this study --- p.29 / Chapter Chapter II --- Materials and Methods --- p.30 / Chapter 2.1 --- Organism and growth conditions --- p.30 / Chapter 2.2 --- Cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.30 / Chapter 2.3 --- Treatment of DDE by living P. pulmonarius --- p.31 / Chapter 2.3.1 --- Optimization of DDE removal in broth system --- p.31 / Chapter 2.3.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.32 / Chapter 2.3.1.2 --- Effects of inoculum size on the removal of DDE --- p.33 / Chapter 2.3.1.3 --- Effects of incubation time on the removal of DDE and transcriptional profiles of the ligninolytic enzyme-coding genes --- p.33 / Chapter 2.3.2 --- Optimization of DDE removal in soil system --- p.34 / Chapter 2.3.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.34 / Chapter 2.3.2.2 --- Effects of inoculum size on the removal of DDE --- p.35 / Chapter 2.3.2.3 --- Effects of incubation time on the removal of DDE --- p.35 / Chapter 2.3.2.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.35 / Chapter 2.4 --- Treatment of DDE by 1st SMC of p. pulmonarius grown on straw-based compost --- p.36 / Chapter 2.4.1 --- Optimization of DDE removal in soil system --- p.36 / Chapter 2.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.36 / Chapter 2.5.1 --- Optimization of DDE removal in broth system --- p.36 / Chapter 2.5.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.37 / Chapter 2.5.1.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.37 / Chapter 2.5.1.3 --- Effects of incubation time on the removal of DDE --- p.37 / Chapter 2.5.2 --- Optimization of DDE removal in soil system --- p.37 / Chapter 2.5.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.38 / Chapter 2.5.2.2 --- Effects of amount of crude enzyme preparations on the removal of DDE --- p.38 / Chapter 2.5.2.3 --- Effects of incubation time on the removal of DDE --- p.38 / Chapter 2.6 --- Soil characterization --- p.39 / Chapter 2.6.1 --- Identification of organic contaminants in soil sample from Gene Garden using Gas Chromatography/Mass Spectrometry (GC/MS) --- p.39 / Chapter 2.6.2 --- Determination of soil texture --- p.42 / Chapter 2.6.3 --- Fresh soil/air-dried sample moisture --- p.44 / Chapter 2.6.4 --- "Soil pH, electrical conductivity & salinity" --- p.44 / Chapter 2.6.5 --- Total organic carbon contents --- p.44 / Chapter 2.6.6 --- Total nitrogen and total phosphorus --- p.44 / Chapter 2.6.7 --- Available nitrogen --- p.45 / Chapter 2.6.8 --- Available phosphorus --- p.45 / Chapter 2.6.9 --- Potassium value --- p.46 / Chapter 2.7 --- Quantification of residual DDE level --- p.47 / Chapter 2.7.1 --- Preparation of DDE stock solution --- p.47 / Chapter 2.7.2 --- Extraction and quantification of DDE using Gas Chromatography with Electron Capture Detector (GC/μECD) --- p.47 / Chapter 2.7.3 --- Identification of DDE breakdown products by GC/MS --- p.50 / Chapter 2.8 --- Extraction of protein and ligninolytic enzymes --- p.53 / Chapter 2.8.1 --- Protein assay --- p.53 / Chapter 2.8.2 --- Laccase assay --- p.53 / Chapter 2.8.3 --- Manganese peroxidase assay --- p.54 / Chapter 2.8.4 --- Calculation of activity and specific activity of laccase and manganese peroxidase --- p.54 / Chapter 2.9 --- Estimation of fungal biomass --- p.55 / Chapter 2.9.1 --- Preparation of ergosterol standard solution --- p.56 / Chapter 2.9.2 --- Analysis of ergosterol content --- p.56 / Chapter 2.10 --- Expression of the ligninolytic enzyme-coding genes --- p.58 / Chapter 2.10.1 --- Preparation of ribonuclease free reagents and apparatus --- p.58 / Chapter 2.10.2 --- RNA isolation and purification --- p.58 / Chapter 2.10.3 --- cDNA synthesis --- p.59 / Chapter 2.10.4 --- Semi-quantification of ligninolytic enzyme-coding gene expression by RT-PCR --- p.59 / Chapter 2.11 --- Preparation of crude enzyme preparations from P. pulmonarius compost --- p.63 / Chapter 2.12 --- "Assessment criteria: removal efficiency, RE, and removal capacity, RC" --- p.63 / Chapter 2.13 --- Statistical analysis “ --- p.64 / Chapter Chapter III --- Results --- p.65 / Chapter 3.1 --- Soil characterization --- p.65 / Chapter 3.2 --- Cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.66 / Chapter 3.2.1 --- Mushroom yield --- p.66 / Chapter 3.2.2 --- Protein content --- p.66 / Chapter 3.2.3 --- Specific ligninolytic enzymes activities --- p.66 / Chapter 3.2.4 --- Ergosterol content --- p.69 / Chapter 3.2.5 --- Ligninolytic enzymes productivities --- p.69 / Chapter 3.2.6 --- Expression of the ligninolytic enzyme-coding genes during solid-state-fermentation --- p.72 / Chapter 3.3 --- Treatment of DDE by living P. pulmonaruis --- p.78 / Chapter 3.3.1 --- Optimization of DDE removal in broth system --- p.78 / Chapter 3.3.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.78 / Chapter 3.3.1.1.1 --- Effects of DDE on biomass development --- p.78 / Chapter 3.3.1.1.2 --- Protein content --- p.78 / Chapter 3.3.1.1.3 --- Specific ligninolytic enzyme activities --- p.78 / Chapter 3.3.1.1.4 --- Ligninolytic enzyme productivities --- p.79 / Chapter 3.3.1.1.5 --- DDE removal and removal capacity --- p.79 / Chapter 3.3.1.2 --- Effects of inoculum sizes on the removal of DDE --- p.84 / Chapter 3.3.1.2.1 --- Effects of DDE on biomass development --- p.84 / Chapter 3.3.1.2.2 --- Protein content --- p.84 / Chapter 3.3.1.2.3 --- Specific ligninolytic enzyme activities --- p.85 / Chapter 3.3.1.2.4 --- Ligninolytic enzyme productivities --- p.85 / Chapter 3.3.1.2.5 --- DDE removal and removal capacity --- p.85 / Chapter 3.3.1.3 --- Effects of incubation time on the removal of 4.0 mM DDE/g biomass --- p.89 / Chapter 3.3.1.3.1 --- Effects of DDE on biomass development --- p.89 / Chapter 3.3.1.3.2 --- Protein content --- p.89 / Chapter 3.3.1.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.89 / Chapter 3.3.1.3.4 --- DDE removal and removal capacity --- p.90 / Chapter 3.3.1.3.5 --- Putative degradation derivatives --- p.90 / Chapter 3.3.1.3.6 --- Expression of the ligninolytic enzyme-coding genes during the removal of 4.0 mM DDE/g biomass --- p.94 / Chapter 3.3.1.4 --- Effects of incubation time on the removal of 10.0 mM DDE/g biomass --- p.100 / Chapter 3.3.1.4.1 --- Effects of DDE on biomass development --- p.100 / Chapter 3.3.1.4.2 --- Protein content --- p.100 / Chapter 3.3.1.4.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.100 / Chapter 3.3.1.4.4 --- Expression of the ligninolytic enzyme-coding genes during the removal of 10.0 mM DDE/g biomass --- p.102 / Chapter 3.3.2 --- Optimization of DDE removal in soil system --- p.107 / Chapter 3.3.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.107 / Chapter 3.3.2.1.1 --- Ergosterol content --- p.107 / Chapter 3.3.2.1.2 --- Protein content --- p.107 / Chapter 3.3.2.1.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.107 / Chapter 3.3.2.1.4 --- DDE removal and removal capacity --- p.108 / Chapter 3.3.2.2 --- Effects of inoculum sizes on the removal of DDE --- p.111 / Chapter 3.3.2.2.1 --- Ergosterol content --- p.111 / Chapter 3.3.2.2.2 --- Protein content --- p.111 / Chapter 3.3.2.2.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.111 / Chapter 3.3.2.2.4 --- DDE removal and removal capacity --- p.112 / Chapter 3.3.2.3 --- Effects of incubation time on the removal of DDE --- p.115 / Chapter 3.3.2.3.1 --- Ergosterol content --- p.115 / Chapter 3.3.2.3.2 --- Protein content --- p.115 / Chapter 3.3.2.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.115 / Chapter 3.3.2.3.4 --- DDE removal and removal capacity --- p.116 / Chapter 3.3.2.3.5 --- Putative degradation derivatives --- p.116 / Chapter 3.3.2.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.121 / Chapter 3.4 --- Treatment of DDE by 1st SMC of p. pulmonarius grown on straw-based compost --- p.127 / Chapter 3.4.1 --- Optimization of DDE removal in soil system --- p.127 / Chapter 3.4.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.127 / Chapter 3.4.1.1.1 --- Ergosterol content --- p.127 / Chapter 3.4.1.1.2 --- Protein content --- p.127 / Chapter 3.4.1.1.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.127 / Chapter 3.4.1.1.4 --- DDE removal and removal capacity --- p.128 / Chapter 3.4.1.2 --- Effects of inoculum sizes on the removal of DDE --- p.132 / Chapter 3.4.1.2.1 --- Ergosterol content --- p.132 / Chapter 3.4.1.2.2 --- Protein content --- p.132 / Chapter 3.4.1.2.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.132 / Chapter 3.4.1.2.4 --- DDE removal and removal capacity --- p.133 / Chapter 3.4.1.3 --- Effects of incubation time on the removal of DDE --- p.136 / Chapter 3.4.1.3.1 --- Ergosterol content --- p.136 / Chapter 3.4.1.3.2 --- Protein content --- p.136 / Chapter 3.4.1.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.136 / Chapter 3.4.1.3.4 --- DDE removal and removal capacity --- p.137 / Chapter 3.4.1.3.5 --- Putative degradation derivatives --- p.137 / Chapter 3.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.142 / Chapter 3.5.1 --- The crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.142 / Chapter 3.5.2 --- Optimization of DDE removal in broth system --- p.143 / Chapter 3.5.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.143 / Chapter 3.5.2.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.145 / Chapter 3.5.2.3 --- Effects of incubation time on the removal of DDE --- p.147 / Chapter 3.5.2.4 --- Putative degradation derivatives --- p.147 / Chapter 3.5.3 --- Optimization of DDE removal in soil system --- p.151 / Chapter 3.5.3.1 --- Effects of initial DDE concentration on the removal of DDE --- p.151 / Chapter 3.5.3.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.151 / Chapter 3.5.3.3 --- Effects of incubation time on the removal of DDE --- p.154 / Chapter 3.5.3.4 --- Putative degradation derivatives --- p.154 / Chapter Chapter IV --- Discussions --- p.158 / Chapter 4.1 --- Quantification of the expression of the ligninolytic enzyme-coding genes --- p.158 / Chapter 4.2 --- Artificial cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.164 / Chapter 4.3 --- Treatment of DDE by living P. pulmonarius --- p.166 / Chapter 4.3.1 --- Optimization of DDE removal in broth system --- p.166 / Chapter 4.3.2 --- Optimization of DDE removal in soil system --- p.169 / Chapter 4.3.3 --- Phylogeny of the ligninolytic enzyme-coding genes --- p.170 / Chapter 4.3.3.1 --- Laccase coding genes --- p.170 / Chapter 4.3.3.2 --- MnP coding genes --- p.175 / Chapter 4.3.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.178 / Chapter 4.4 --- Treatment of DDE by 1st SMC of P. pulmonarius grown on straw-based compost --- p.183 / Chapter 4.4.1 --- Optimization of DDE removal in soil system --- p.183 / Chapter 4.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.184 / Chapter 4.6 --- Cost-effectiveness of the bioremediation method --- p.185 / Chapter 4.7 --- Further investigations --- p.194 / Chapter Chapter V --- Conclusions --- p.197 / References --- p.199

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