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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.
31

A Gill Filament EROD Assay : Development and Application in Environmental Monitoring

Jönsson, Maria January 2003 (has links)
A gill filament-based assay for the cytochrome P450 1A (CYP1A)-catalysed activity ethoxyresorufin O-deethylase (EROD) was developed in rainbow trout (Oncorhynchus mykiss) and applied to Atlantic salmon (Salmo salar), Arctic charr (Salvelinus alpinus), Atlantic cod (Gadus morhua), saithe (Pollachius virens), and spotted wolffish (Anarhichas minor). Exposure to waterborne β-naphthoflavone (βNF; 10-6 M) induced branchial EROD activity in all species but the spotted wolffish. In rainbow trout exposed to low concentrations of benzo[a]pyrene (BaP; 10-9 M) and the textile dye indigo (10-8 M) the gills responded more rapidly than the liver to BaP, and indigo induced branchial but not hepatic EROD activity. A CYP1A-dependent BaP adduct formation was shown in gills of fish exposed to waterborne 3H-BaP, i.e. the adduct formation was enhanced by βNF and blocked by ellipticine (CYP1A inhibitor). The predominant location for BaP adducts was the secondary lamellae (most exposed part of the gill filament), whereas the CYP1A enzyme was also present in the primary lamellae of the gill filament. Hence, in addition to the cell-specific expression of CYP1A an important determinant for the localisation of adducts seemed to be the bioavailability of BaP. This idea is supported by the fact that the CYP1A enzyme was induced only in secondary lamellae by BaP (10-7 M) and indigo (10-6 M), whereas it was induced in both primary and secondary lamellae by 3,3´,4,4´,5-pentachlorobiphenyl (10-8 M). Apparently, readily metabolised inducers (BaP and indigo) are biotransformed in the secondary lamellae. My results show that gill filament EROD activity is a sensitive biomarker of exposure to waterborne dioxin-like pollutants, and that the assay has potential for use in monitoring. Furthermore, the results suggest that readily metabolised dioxin-like compounds absorbed via the gills may undergo first-pass metabolism in the gill cells and therefore remain undetected by monitoring of EROD activity in the liver.
32

Utvärdering av ICC-profiler och profil-inställningar för HP Indigo Press 1000

Astrén, Johanna January 2003 (has links)
Det nystartade digitaltryckeriet Digaloo planerar att inom en snar framtid införa ICC-hantering i sittarbetsflöde. Med anledning av detta har en studie utförts där antalet erfordrade ICC-profiler undersöktssamt vilka akromatiska inställningar som bäst lämpar sig för tryckeriets HP Indigo Press 1000.Testtryckning utfördes på sex av Digaloos mest använda papperskvaliteter. Genom inläsning av testkartorhar de olika papperskvaliteternas reproducerbara färgrymder åskådliggjorts. Grundat på resultatetfrån denna testtryckning framställdes ICC-profiler för valda papperskvaliteter. Dessa genereradesmed olika inställningar för akromatisk repro och TIC (Total Ink Coverage). Vid en andra testtryckninganvändes dessa ICC-profiler för konvertering av mellanton-, natt- och snöbilder, vilka trycktespå olika papperskvaliteter.Resultatet från den första testtryckningen visar att HP Indigo Press 1000 återger störst förgrymd påpapperskvaliteten Silverblade Silk, tätt följd av Silverblade Art. De minsta färgrymderna reproduceraspå Lessebo Linné Gultonat och Lessebo Linné Naturvit.Vid perceptuell bedömning av de olika bilderna blev resultatet att bäst tryckresultat uppnås medpappersspecifika ICC-profiler. Detta gäller dock endast i två av tre fall. Vid bedömning av bäst lämpadTIC ansågs den idag på Digaloo använda nivån som mycket dålig. Genom att antingen sänka eller höjadenna nivå bedömdes tryckresultatet öka i kvalitet.Slutligen visar studien även att akromatik i form av UCR ger bäst bildåtergivning i mellanton- ochnattbilder på de valda papperskvaliteterna. De olika graderna av GCR i snöbilder anses dock passaolika bra beroende på vilken papperskvalitet som används.
33

Utvärdering av digitala provtryckssystem

Vendel, Per, Olsson, Tomas January 2002 (has links)
Six different Digital Proofing Systems from three different techniques have been evaluated as totechnique, printing quality, economy and usability. Digital proof from two paper qualities, coatedand uncoated, has been compared with references printed in offset, to see how good they match eachother. Only two Proofing Systems manage to print on reference paper. The other Proofing Systemsuse special paper for digital proof.Measurements and visuell judgement show that the Digital Proofing Systems visualise referencepictures with quite good quality. Proof optimised for coated paper visualise the colours with goodresult. Proof optimised for uncoated paper shows higher quality than the references, which depends onthe surface of the proofing paper. Comparison between reference paper and proofing paper has takenplace as to differences in colour and paper quality.The Digital Proofing Systems are fully automatic, which demand a quite comprised education forcorrect handling. The purchase price and printing costs vary considerably between the ProofingSystems.
34

Ozonation Of A Denim Producing Textile Industry Wastewater

Morali, Eyup Kaan 01 September 2010 (has links) (PDF)
Denim production is one of the leading sub-sectors of textile industry which basically generates highly colored indigo dyeing effluents. In the present study, ozonation was applied to the indigo-dyeing effluent(COD=820 mg/L / color=5500 Pt-Co), and to the whole effluent from a denim-producing plant before(COD=2750 mg/L / color=3950 Pt-Co) and after(COD=800 mg/L,color=3700 Pt-Co) biological treatment for degradation/detoxification purposes. Ozonation was also tried in the wastewater of the plant(COD=3100 mg/L / color=4500 Pt-Co) that would be produced after some foreseen cleaner production measures / caustic recovery and reusing of dyeing process wastewater. When applied to indigo-dyeing wastewater / ozonation provided 95% color and 61% COD removals at 1320 mg/h ozone dose within 60 minutes The optimum pH was evaluated as 4 when indigo-dyeing wastewater exposed to ozonation at different pHs(1.6-12.3). On the other side, ozonation applied as pre-treatment to the plant effluent provided 86% color and 46% COD removals with 3240 mg/h ozone dose in 70 minutes. Less satisfactory results were obtained when ozonation was tried in the wastewater after measures, with 86% color and 31% COD removals at 3960 mg/h ozone dose in 80 minutes. When applied to the biologically-treated effluent / at 420 mg/h ozone dose and within 40 minutes, ozonation removed 47% of influent COD and 96% of influent color indicating better performance of ozonation in postoxidation. In order to assess possible improvements on ozonation with the addition of H2O2, different concentrations were tried, but no significant improvement was obtained. The improvement in BOD5/COD index was also determined for the ozonetreated plant effluent to measure the effects of ozonation on biodegradability and found out that BOD5/COD ratio has improved to 0.39 from 0.22.
35

The Chiltern Standard newspaper, 1859-1860: an expression of community life

Williams, Jennifer Ann January 1986 (has links)
This thesis is a study of a Victorian country newspaper, the Chiltern Standard during the period 1859-60. Using the Indigo-Chiltern goldfield (discovered in 1858) as a case study, it investigates how the life of the community was expressed through the pages of its local paper.
36

Anti-brood parasite defenses and nest-site selection by forest-edge songbirds in Central Missouri /

Burhans, Dirk E., January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
37

Anti-brood parasite defenses and nest-site selection by forest-edge songbirds in Central Missouri

Burhans, Dirk E., January 1996 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
38

CRIANÇAS ÍNDIGO E COM ALTAS HABILIDADES/SUPERDOTAÇÃO: APROXIMAÇÕES E DISTANCIAMENTOS NO CONTEXTO EDUCATIVO / INDIGO CHILDREN AND WITH HIGH SKILLS/GIFTEDNESS: APPROACHES AND DISTANCES IN THE EDUCATIONAL CONTEXT

Costa, Anelise dos Santos da 16 April 2013 (has links)
The educational context, more precisely the school, has been the scene of several discussions, both with regard to working methods, teaching and public policies, as well as in relation to the subject that make up this space being noted that, currently, there are many differences with respect to the characteristics of the students who attend. In this sense, the present scientific interaction research theme is indigo children and with high skills/giftedness in the school context, considering the peculiar characteristics presented by these subjects. This research had as general objective to investigate which approaches and distances in the process of education of the students with high abilities/indigo and giftedness. Specific objectives are outlined: draw up a cast of features of the indigo child, directed to the school context, analyze how teachers perceive the indigo features and high skills/giftedness, evident in the school context and understand how the relationships of indigo and features high skills/giftedness interfere in the process of education of these subjects. To this end, the methodology of this research appears as a qualitative approach, since considering the relatively little explored theme using different data collection instruments. The background of this research is not to just get a new categorization of subject or behaviors, but in order to search for new knowledge that can help in the transformation of current education, still based on the principles of normalization of the subject. The analysis of the research included the examination of the indigo features cast, shortly after with the analysis of interviews given by teachers about the characteristics of their students. In the discussion were raised approaches regarding the characteristics and perceived indicators, culminating in the realization that there is a gap in the plan's discussion of spirituality, widely described by theoretical feature as an integral element of indigo and important features for complete understanding of the subject, as well as to meet the demand that the current society requires. Keywords: High skills/giftedness. Indigo children. Education / O contexto educacional, mais precisamente o escolar, tem sido palco de diversas discussões, tanto no que concerne às metodologias de trabalho, didática e políticas públicas, quanto em relação aos sujeitos que compõem tal espaço sendo observado que, atualmente, muitas são as diferenças no que tange às características dos estudantes que o frequentam. Neste sentido, a presente interlocução científica apresenta como temática de investigação crianças índigo e com altas habilidades/superdotação no contexto escolar, tendo em vista as características peculiares apresentadas por estes sujeitos. Esta investigação teve como objetivo geral investigar quais as aproximações e distanciamentos no processo de escolarização dos estudantes índigo e com altas habilidades/superdotação. Como objetivos específicos delineou-se: elaborar um elenco de características da criança índigo, direcionado ao contexto escolar, analisar como os professores percebem as características índigo e de altas habilidades/superdotação, evidentes no contexto escolar e compreender como as relações das características índigo e de altas habilidades/superdotação interferem no processo de escolarização destes sujeitos. Para tanto, a metodologia desta pesquisa configura-se como uma abordagem qualitativa, pois considerando o tema relativamente pouco explorado utilizou-se diferentes instrumentos de coleta de dados. A justificativa desta investigação está em não apenas buscar uma nova categorização de sujeitos ou comportamentos, mas na intenção de procurar novos conhecimentos que possam auxiliar na transformação da educação atual, ainda pautada em princípios de normalização do sujeito. A análise da investigação contou com a apreciação do elenco de características índigo, logo após com a análise das entrevistas concedidas pelas professoras a cerca das características de seus estudantes. Na discussão foram levantadas as aproximações a respeito das características e indicadores percebidos, culminando na percepção de que há um distanciamento na discussão do plano da espiritualidade, caraterística amplamente descrita pelo referencial teórico como elemento integrante das características índigo e importante para compreensão total do sujeito, bem como para atender a demanda que a sociedade atual necessita.
39

Microsystèmes capteurs de gaz sélectifs au dioxyde d'azote associant structures semi-conducteurs et filtres chimiques (indigo ou/et nanomatériaux carbonés) destinés au contrôle de la qualité de l'air / Nitrogen dioxide selective gas sensor microsystems combining semiconductor structures and chemical filters (indigo and/or carbonaceous nanomaterials) for air quality control

Spinelle, Laurent 13 March 2012 (has links)
Ce manuscrit est consacré à l’étude et au développement de microsystèmes capteurs de gaz sélectifs au dioxyde d’azote, destinés au contrôle de la qualité de l’air atmosphérique. La stratégie que nous avons développée consiste à associer une structure sensible à base de matériaux semi-conducteurs partiellement sélectifs aux gaz oxydants et des filtres sélectifs à l’ozone. L’objectif premier est la mise en oeuvre et la caractérisation de matériaux chimiques strictement imperméables à l’ozone (O3) et non-réactifs vis-à-vis du dioxyde d’azote (NO2). Notre choix s’est focalisé sur un matériau moléculaire, l’indigo, connu pour sa réactivité vis-à-vis de O3, et plusieurs nanomatériaux carbonés. Pour ces derniers, la possibilité de conformer leurs textures, leurs morphologies et leurs chimies de surface par traitements thermiques, chimiques et mécaniques, permet d’étendre le panel de matériaux potentiels et d’identifier les facteurs d’influence de leur réactivité avec les espèces gazeuses. La caractérisation de l’ensemble de ces matériaux a nécessité l’utilisation de techniques adaptées et complémentaires (adsorption de N2 à 77 K, spectroscopies Raman, XPS, IR en mode ATR, RPE et NEXAFS). Les filtres chimiques les plus efficaces (hauts rendements de filtration et grande durabilité) ont été sélectionnés d’après des tests de soumission aux gaz selon une méthodologie adaptée. Enfin, l’association de ces meilleurs filtres et de la structure capteur a conduit à l’élaboration de prototypes microsystèmes capteurs de gaz optimisés. De plus, une contribution à la compréhension des mécanismes d’interaction de l’indigo et de certains nanocarbones avec O3 et NO2 a aussi permis d’améliorer le microsystème en développant des méthodologies pertinentes et innovantes mais également en réalisant la synthèse de nouveaux filtres indigo / nanocarbone. / This work is devoted to the study and the development of gas sensors microsystems highly selective to nitrogen dioxide, dedicated to the air quality control. The strategy developed consists in the implementation of a sensitive structure based on semiconductor materials partially selective to oxidizing gases associated to an ozone selective filter. The first objective is the development of chemical filters strictly impervious to ozone (O3) and non-reactive towards the nitrogen dioxide (NO2). We have chosen a molecular material, indigo, well-known for its reactivity towards O3, and several carbonaceous nanomaterials. For these one, the possibility to modify their textures, their morphologies and their surface chemistries by chemical, mechanical and thermic treatments, enables us to extend the range of potential materials and to identify the factors of influence on their reactivity with gaseous species. The characterization of all these materials required the use of appropriate and complementary techniques (N2 adsorption at 77 K, Raman, XPS, IR in ATR mode, EPR and NEXAFS). The more efficient filters (high filtering yield and life-time) have been selected by means of specific tests of gas exposure. Finally, the association of the best filter and the sensitive structure has led to the development of optimized gas sensors microsystems prototypes.
40

Engineering cytochrome P450-reductase fusion enzymes for biocatalysis

Kelly, Paul January 2014 (has links)
Cytochromes P450 (P450s) are a superfamily of heme-thiolate monooxygenases. They catalyse a wide variety of reactions on a vast number of substrates and are of particular interest for biocatalyst development due to their ability to oxidise non-activated C-H bonds. Fusion of a P450 to a suitable redox partner protein produces a catalytically self-sufficient enzyme and removes the need to produce electron transfer proteins separately. The well-studied bacterial protein P450cam (Pseudomonas putida) has been fused to the reductase (RhFRed) from the natural fusion protein P450-RhF (Rhodococcus sp.). The P450cam-RhFRed system catalyses the oxidation of camphor and several non-natural substrates and served as the basis for P450cam re-engineering in this current project, with the aim of expanding the substrate scope towards a more mammalian-like activity. The P450cam active site was partitioned into seven paired amino acids and each pair randomised in turn to generate seven sub-libraries of P450cam variants. These were screened for activity using a specially developed colony screen for detection of the blue pigment indigo. In total 94 new variants were identified and then pooled for secondary screening on a number of new substrates, identifying potentially novel activities within the ‘indigo positive’ population. In a separate ‘chimeragenesis’ approach substrate recognition sites (SRSs) within P450cam were targeted for exchange with equivalent portions from a number of human P450s. The B’ helix and F-G loop regions from CYPs 1A2, 2C8, 2D6 and 3A4 were grafted onto the P450cam structure and several of the B’ helix swaps were produced as soluble proteins. The P450cam-2C8-B’-RhFRed chimera gave a Soret peak at 420 nm in the Fe(II)-CO state although an additional substitution next to the proximal cysteine appeared to restore a P450-like state. SRS-exchange therefore offered some insight into structural modularity in P450s, providing a basis for further biocatalyst development.

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