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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.
61

Undersökning av exponeringsindex för bildplattesystem inför optimeringsarbete / Examination of Exposure Indexes for Image Plate Systems before Optimization

Lömäng, Magnus January 2004 (has links)
The county hospital of Dalarna has for the last couple of years carried through a process of digitalization. The result is that within the county it exists image plate systems from two different manufacturers. In an attempt to create a tool for dose optimization and dose surveillance the county of Dalarna would like to investigate if the exposure index from Agfa and Fuji is suitable as a dose indicator. An investigation of the exposure index, S, from Fuji has already been done. This thesis has been continuing the investigation by evaluating the stability of the exposure index, lgM, from Agfa. Simultaneously an observation if there is a simple relation between the exposure indicators from Agfa and Fuji has been performed. The result showed that the average of lgM, for a set of images from the same type of examination, is appropriate as a dose indicator to the image plate for that specific examination type and X-ray equipment. The usefulness is linked to the same tube voltage and Speed Class for a specific examination, and is to a certain degree restricted by the collimating. There is a relation between the exposure index from Agfa and Fuji, and there is in a simple way possible to transform S-values to lgM-values for comparison. The relation turned out to be examination specific.
62

Analys av vävnadsprover med endimensionell elektrofores

Larsson, Frida January 2007 (has links)
<p>The following project has been made in collaboration with, Denator AB, a biotechnology enterprise. One-dimensional electrophoreses have been used to analyze protein contents of tissue samples. Tissue samples have been either treated according to the company´s newly developed tissue treatment technique or not treated at all and comparisons between these samples have been made. In order to see differences in protein patterns between samples more clearly, a conversion method has been developed where electrophoresis gel visual patterns are used to produce curves, similar to densitometer curves.</p><p>Denator AB would like to know if the proteins in their treated samples will change visibly over 48 h when incubated at room temperature. This has been investigated using the above mentioned method. A comparison has also been made using untreated samples incubated in the same way.</p><p>The analyses have been made at two gel densities, 10% and 12%. The series of samples consisted of both treated and untreated samples. Incubations were made for different time intervals in room temperature, up to 48 h. Gels were scanned and the files were used for producing curves where the colour intensity along a track was used for ordinate and the protein travel distance was used for abscissa.</p><p>Using this method, no change in patterns of Denator treated samples could be seen, strongly indicating efficient conservation of the samples. The untreated samples, however, show visible changes with time, indicating that the sample proteins were</p><p>partly decomposed into smaller fragments with time. A striking result of the analyses is a clearly visible difference in the original patterns of untreated and treated samples before incubation. This indicate that non treated samples undergo a very quick process of decay.</p>
63

Analys av vävnadsprover med endimensionell elektrofores

Larsson, Frida January 2007 (has links)
The following project has been made in collaboration with, Denator AB, a biotechnology enterprise. One-dimensional electrophoreses have been used to analyze protein contents of tissue samples. Tissue samples have been either treated according to the company´s newly developed tissue treatment technique or not treated at all and comparisons between these samples have been made. In order to see differences in protein patterns between samples more clearly, a conversion method has been developed where electrophoresis gel visual patterns are used to produce curves, similar to densitometer curves. Denator AB would like to know if the proteins in their treated samples will change visibly over 48 h when incubated at room temperature. This has been investigated using the above mentioned method. A comparison has also been made using untreated samples incubated in the same way. The analyses have been made at two gel densities, 10% and 12%. The series of samples consisted of both treated and untreated samples. Incubations were made for different time intervals in room temperature, up to 48 h. Gels were scanned and the files were used for producing curves where the colour intensity along a track was used for ordinate and the protein travel distance was used for abscissa. Using this method, no change in patterns of Denator treated samples could be seen, strongly indicating efficient conservation of the samples. The untreated samples, however, show visible changes with time, indicating that the sample proteins were partly decomposed into smaller fragments with time. A striking result of the analyses is a clearly visible difference in the original patterns of untreated and treated samples before incubation. This indicate that non treated samples undergo a very quick process of decay.
64

Enzyme substrate solvent interactions : a case study on serine hydrolases

Fransson, Linda January 2008 (has links)
Reaction rates and selectivities were measured for transacylation of fatty acid esters in solvents catalysed by Candida antarctica lipase B and by cutinase from Humicola insolens. With these enzymes classical water-based enzymology can be expanded to many different solvents allowing large variations in interaction energies between the enzymes, the substrates and the surrounding. Further ,hydrolysis reactions catalysed by Bacillus subtilis esterase 2 were investigated. Thermodynamics analyses revealed that the enzyme contribution to reaction rate acceleration compared to acid catalysis was purely entropic. On the other hand, studies of differences in activation entropy and enthalpy between enantiomers and between homologous esters showed that high substrate specificity was favoured by enthalpic stabilisation. Solvent was found to have a profound effect on enzyme catalysis, affecting both reaction rate and selectivity. Differences in substrate solubility will impact enzyme specificity since substrate binding is an equilibrium between enzyme-bound substrate and substrate in free solution. In addition, solven tmolecules were found to act as enzyme inhibitors, showing both competitive and non-competitive behaviour. In several homologous data series enthalpy-entropy compensation relationships were encountered. A possible extrathermodynamic relationship between enthalpy and entropy can easily be lost under co-varying errors propagated from the experiments. From the data in this thesis, one instance was found of a real enthalpy-entropy compensation that could be distinguished from statistical errors, while other examples could not be verified. / QC 20100722
65

Multivariate monitoring, modelling and control for stabilization of bioprocesses /

Cimander, Christian, January 2002 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2002. / Härtill 5 uppsatser.
66

Movement artifact reduction in laser Doppler blood flowmetry : myocardial perfusion applications /

Karlsson, M. G. Daniel, January 2005 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 5 uppsatser.
67

Citrus Waste Biorefinery : Process Development, Simulation and Economic Analysis

Pourbafrani, Mohammad January 2010 (has links)
The production of ethanol and other sustainable products including methane, limonene and pectin from citrus wastes (CWs) was studied in the present thesis. In the first part of the work, the CWs were hydrolyzed using enzymes – pectinase, cellulase and β-glucosidase – and the hydrolyzate was fermented using encapsulated yeasts in the presence of the inhibitor compound ‘limonene’. However, the application of encapsulated cells may be hampered by the high price of encapsulation, enzymes and the low stability of capsules’ membrane at high shear stresses. Therefore, a process based on dilute-acid hydrolysis of CWs was developed. The limonene of the CWs was effectively removed through flashing of the hydrolyzate into an expansion tank. The sugars present in the hydrolyzate were converted to ethanol using a flocculating yeast strain. Then ethanol was distilled and the stillage and the remaining solid materials of the hydrolyzed CWs were anaerobically digested to obtain methane. The soluble pectin content of hydrolyzate can be precipitated using the produced ethanol. One ton of CWs with 20% dry weight resulted in 39.64 l ethanol, 45 m3 methane, 8.9 l limonene, and 38.8 kg pectin. The feasibility of the process depends on the transportation cost and the capacity of CW. For example, the total cost of ethanol with a capacity of 100,000 tons CW/year was 0.91 USD/L, assuming 10 USD/ton handling and transportation cost of CW to the plant. Changing the plant capacity from 25,000 to 400,000 tons CW per year results in reducing ethanol costs from 2.55 to 0.46 USD/L in an economically feasible process. Since this process employs a flocculating yeast strain, the major concern in design of the bioreactor is the sedimentation of yeast flocs. The size of flocs is a function of sugar concentration, time and flow. A CFD model of bioreactor was developed to predict the sedimentation of flocs and the effect of flow on distribution of flocs. The CFD model predicted that the flocs sediment when they are larger than 180 micrometer. The developed CFD model can be used in design and scale-up of the bioreactor. For the plants with low CW capacity, a steam explosion process was employed to eliminate limonene and the treated CW was used in a digestion plant to produce methane. The required cost of this pretreatment was about 0.90 million dollars for 10,000 tons/year of CWs. / <p><strong>Sponsorship</strong>:</p><p>Sparbankstiftelsen Sjuhärad, Kommunalförbundet i Sjuhärad, Brämhults juice AB</p>
68

Immateriella tillgångar och lönsamhet : Komparativ studie av bioteknikföretag

Zettechelme, Gabriella, Kohvakka, Carina January 2006 (has links)
<p>Immateriella tillgångar har blivit allt vanligare att investera i, och detta har lett till en stor uppmärksamhet kring deras redovisning och värdering. År 2005 infördes i Sverige IFRS/IAS, internationell redovisningsstandard. Dessa regler är tänkta att förändra redovisningen till det bättre med mål att ge en så korrekt och verklighetsnära bild som möjligt. </p><p>Det som denna uppsats tar upp är redovisning av bioteknikföretags immateriella tillgångar och vilken finansiell påverkan redovisningsreglerna har genom att räkna ut företagens lönsamhet. Uppsatsen är inriktad på att forska kring immateriella tillgångar och lönsamhet i fyra bioteknikföretag, nämligen Medivir, Q-Med, Karo Bio och BioGaia där en fallstudie har utförts. De lönsamhetsmått som uppsatsen inriktats mot är räntabilitet per eget kapital, räntabilitet på totalt kapital och vinstmarginal.</p><p>Det resultat undersökningen ger är att Q-Med och BioGaia som har större andelar immateriella tillgångar redovisade i procent av de totala tillgångarna, visar en positiv lönsamhet. Medivir och Karo Bio som däremot har lägre andelar eller inga immateriella tillgångar redovisade i procent av totala tillgångar, visar en negativ lönsamhet.</p>
69

Genetisk artbestämning och karaktärisering av Trypanosoma theileri

Salmijärvi, Sari January 2008 (has links)
No description available.
70

Databases for antibody-based proteomics

Björling, Erik January 2008 (has links)
Humans are believed to have ~20,500 protein-coding genes andmuch effort has over the last years been put into the characterizationand localization of the encoded proteins in order to understand theirfunctions. One such effort is the Human Proteome Resource (HPR)project, started in Sweden 2003 with the aim to generate specificantibodies to each human protein and to use those antibodies toanalyze the human proteome by screening human tissues and cells.The work reported in this thesis deals with structuring of data fromantibody-based proteomics assays, with focus on the importance ofaggregating and presenting data in a way that is easy to apprehend.The goals were to model and build databases for collecting, searchingand analyzing data coming out of the large-scale HPR project and tomake all collected data publicly available. A public website, theHuman Protein Atlas, was developed giving all end-users in thescientific community access to the HPR database with proteinexpression data. In 2008, the Human Protein Atlas was released in its4th version containing more than 6000 antibodies, covering more than25% of the human proteins. All the collected protein expression datais searchable on the public website. End-users can query for proteinsthat show high expression in one tissue and no expression in anotherand possibly find tissue specific biomarkers. Queries can also beconstructed to find proteins with different expression levels in normalvs. cancer tissues. The proteins found by such a query could identifypotential biomarkers for cancer that could be used as diagnosticmarkers and maybe even be involved in cancer therapy in the future.Validation of antibodies is important in order to get reliable resultsfrom different assays. It has been noted that some antibodies arereliable in certain assays but not in others and therefore anotherpublicly available database, the Antibodypedia, has been createdwhere any antibody producer can submit their binders together withthe validation data in order for end users to purchase the bestantibody for their protein target and their intended assay. / QC 20100708

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