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Optimering av biogasproduktion från gödsel / Optimization of Biogas Production from ManureÖzdemir, Gonca January 2009 (has links)
In this study, the bioconversion of manure and silage to biogas by an anaerobic digestion process in batch reactors was studied. Biogas is a valuable alternative energy source, mainly in rural areas. The main aim for the environment is to use biogas as a fuel instead of crude oil or natural gas. In this study, two different parameters were studied to observe the changes in methane productivity. The first three reactors were shaken once per week and the following three reactors were shaken 5 times per week. The results showed that mixing has no major effect on the methane production yield. In the second six reactors a mixture of 1% and 3% silage was added and the results were recorded. When the data from the reactors with just manure was compared to the reactors with 1% and 3% silage, it was seen that the silage increased the production rate and total gas produced. The process stabilization took a long time for digestion with the 3% silage possibly caused by release of too much fatty acids.
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Blinkbeteendebaserad trötthetsdetektering : metodutveckling och validering / Blink behaviour based drowsiness detection : method development and validationSvensson, Ulrika January 2004 (has links)
<p>Electrooculogram (EOG) data was used to develop, adjust and validate a method for drowsiness detection in drivers. The drowsiness detection was based on changes in blink behaviour and classification was made on a four graded scale. The purpose was to detect early signs of drowsiness in order to warn a driver. MATLAB was used for implementation. For adjustment and validatation, two different reference measures were used; driver reported ratings of drowsiness and an electroencephalogram (EEG) based scoring scale. A correspondence of 70 % was obtained between the program and the self ratings and 56 % between the program and the EEG based scoring scale. The results show a possibility to detect drowsiness by analyzing blink behaviour changes, but that inter-individual differences need to be considered. It is also difficult to find a comparable reference measure. The comparability of the blink based scale and the EEG based scale needs further investigation.</p>
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Fel och felkällor vid bäckenmätning / Error and sources of errors in radiological pelvimetryLarsson, Karin January 2004 (has links)
<p>Syftet med detta arbete var att utreda felkällor som förekommer vid användning av olika tekniker/modaliteter vid bäckenmätning. Då det finns risker med röntgenstrålning önskar man reducera stråldosen vid undersökningarna samtidigt som man vill använda sig av en enkel metod. De olika modaliteterna som jämförs är i) direktdigital detektor och bildplatta, ii) bildförstärkarteknikteknik, iii) CT. Den modalitet man använder sig av idag är direktdigital detektor och bildplatta. För att korrigera för förstoring som uppkommer vid röntgenundersökningen placeras en mätsticka i bildfältet. Om mätstickan vinklas mot sagittalplanet blir korrigeringen fel och detta visas i teori och praktiska försök. Bildförstärkare kan användas för att ta sidobilden. Bildförstärkarens geometriska egenskaper ger dessvärre en måttdistorsion så att objekt i det perifera bildfältet blir förstorade mer än objekt centralt belägna. Det har inte framkommit något bra sätt att korrigera för distorsionen. CT har inte använts vid bäckenmätningar på Helsingborgs lasarett tidigare. Att använda topogrammet vid CT- undersökning kan även det vara behäftat med längddistorsion och förslag ges hur man kan korrigera för felet. I CT-snittbilder fås ingen längddistorsion.</p>
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Construction and evaluation of plasma protein multilayers used for local drug deliveryOlof, Sandberg January 2010 (has links)
<p>With the studies performed in this theses the local drug delivery technique FibMat developed by the biotech company AddBIO, was shown to be applicable to other plasma proteins and drugs than the fibrinogen-bisphosphonate combination that is today being commercialized. Hence the potential for a broader field of application was demonstrated. The application targeted today is as a surface modification giving improved strength to bone around screws used in bone implants. The effect of changing protein and manufacturing conditions was studied with null ellipsometry. It was demonstrated that with changes in incubation temperature, pH and salinity the fibrinogen could be successfully exchanged for the plasma proteins human serum albumin and immunoglobulin G. With liquid scintillation counting it was shown that the developed protein multilayers were able to absorb and release the bone strengthening drug alendronic acid in levels comparable to that of the fibrinogen based ditto. Disk susceptibility tests with the bacteria S. Aureus showed a potential for antibacterial functionalization with gentamicin. The release was, in the case of the fibrinogen multilayer, detectable up to 48 hours. Similar test revealed an inability of silver nanoparticle incorporated protein multilayers to achieve inhibitory levels.</p>
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Direct observation of biomolecule adsorption and spatial distribution of functional groups in chromatographic adsorbent particlesLjunglöf, Anders January 2002 (has links)
<p>Confocal microscopy has been used as a tool for studying adsorption of biomolecules to individual chromatographic adsorbent particles. By coupling a fluorescent dye to protein molecules, their penetration into single adsorbent particles could be observed visually at different times during batch uptake. By relating the relative fluorescence intensity obtained at different times to the value at equilibrium, the degree of saturation versus time could be constructed. The use of two different fluorescent dyes for protein labeling and two independent detectors, allowed direct observation of a two-component adsorption process. The confocal technique was also applied for visualization of nucleic acids. Plasmid DNA and RNA were visualized with fluorescent probes that binds to double stranded DNA and RNA respectively. Confocal measurements following single component adsorption to ion exchange particles, revealed an interesting phenomenon. Under certain experimental conditions, development of "inner radial concentration rings" (i.e. adsorbed phase concentrations that are higher at certain radial positions within the particle) were observed. Some examples are given that show how such concentration rings are formed within a particle.</p><p>Methods were also developed for measurement of the spatial distribution of immobilized functional groups. Confocal microscopy was used to investigate the immobilization of trypsin on porous glycidyl methacrylate beads. Artefacts relating to optical length differences could be reduced by use of "contrast matching". Confocal microscopy and confocal micro-Raman spectroscopy, were used to analyze the spatial distribution of IgG antibodies immobilized on BrCN-activated agarose beads. Both these measurement methods indicate an even ligand distribution. Finally, confocal Raman and fluorescence spectroscopy was applied for measurement of the spatial distribution of iminodiacetic- and sulphopropyl groups, using Nd3+ ions as fluorescent probes. Comparison of different microscope objectives showed that an immersion objective should be used for measurement of wet adsorbent particles.</p><p><i>Direct experimental information from the interior of individual adsorbent particles will increase the scientific understanding of intraparticle mass transport and adsorption mechanisms, and is an essential step towards the ultimate understanding of the behaviour of chromatographic adsorbents.</i></p>
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Computational approaches for in-depth analysis of cDNA sequence tagsUnneberg, Per January 2004 (has links)
Major recent improvements in biotechnology have led to an accelerated production of DNA sequences. The completion of the human genome sequence, along with the genomes of more than two hundred other species, has marked the arrival of the genome era. The ultimate goal is to understand the structure and function of genomes and their genes. This thesis has focused on the computational analysis of complementary DNA (cDNA) sequences. These are copies of mRNA transcripts that correspond to the coding regions of genomes. Studying the expression patterns of genes is essential for understanding gene function. Many gene expression profiling techniques generate short sequence tags that derive from transcripts. A pilot study was performed to assess the feasibility of using the pyrosequencing platform for gene expression analysis. The sequences generated by pyrosequencing in most cases (≈ 85%) were long enough (> 18 nucleotides) to uniquely identify the corresponding transcripts through database searches. Aspects of transcript identification by short sequence tags were further investigated in a number of public databases, revealing that a tag length 16-17 nucleotides was sufficient for unique identifi- cation. Longer transcript representations are obtained from expressed sequence tag (EST) sequencing. Method development for the analysis and maintenance of large EST data sets has been performed on data from poplar, which is a tree of commercial interest to the forest biotechnology industry. In 2003 a large ESTsequencing project reached > 100 000 reads, providing a unique resource for tree biology research. ESTs have been grouped into clusters and singletons that represent potential genes. Preliminary analyses have estimated gene content in Populus to be very similar to that of model organism Arabidopsis thaliana. EST data collections provide a rich source for mining polymorphisms. A software application was developed and applied to EST data from two Populus species, and candidate single nucleotide polymorphisms (SNPs) were recorded. A study of genetic variation between the species revealed a striking similarity, with orthologous pairs being > 98% identical on the protein level. Keywords: cDNA, EST, gene expression, SNP, SAGE, polymorphism, assembly, clustering, DNA sequencing, pyrosequencing, mRNA transcript, orthology, tree biotechnology, restriction enzyme
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Direct observation of biomolecule adsorption and spatial distribution of functional groups in chromatographic adsorbent particlesLjunglöf, Anders January 2002 (has links)
Confocal microscopy has been used as a tool for studying adsorption of biomolecules to individual chromatographic adsorbent particles. By coupling a fluorescent dye to protein molecules, their penetration into single adsorbent particles could be observed visually at different times during batch uptake. By relating the relative fluorescence intensity obtained at different times to the value at equilibrium, the degree of saturation versus time could be constructed. The use of two different fluorescent dyes for protein labeling and two independent detectors, allowed direct observation of a two-component adsorption process. The confocal technique was also applied for visualization of nucleic acids. Plasmid DNA and RNA were visualized with fluorescent probes that binds to double stranded DNA and RNA respectively. Confocal measurements following single component adsorption to ion exchange particles, revealed an interesting phenomenon. Under certain experimental conditions, development of "inner radial concentration rings" (i.e. adsorbed phase concentrations that are higher at certain radial positions within the particle) were observed. Some examples are given that show how such concentration rings are formed within a particle. Methods were also developed for measurement of the spatial distribution of immobilized functional groups. Confocal microscopy was used to investigate the immobilization of trypsin on porous glycidyl methacrylate beads. Artefacts relating to optical length differences could be reduced by use of "contrast matching". Confocal microscopy and confocal micro-Raman spectroscopy, were used to analyze the spatial distribution of IgG antibodies immobilized on BrCN-activated agarose beads. Both these measurement methods indicate an even ligand distribution. Finally, confocal Raman and fluorescence spectroscopy was applied for measurement of the spatial distribution of iminodiacetic- and sulphopropyl groups, using Nd3+ ions as fluorescent probes. Comparison of different microscope objectives showed that an immersion objective should be used for measurement of wet adsorbent particles. Direct experimental information from the interior of individual adsorbent particles will increase the scientific understanding of intraparticle mass transport and adsorption mechanisms, and is an essential step towards the ultimate understanding of the behaviour of chromatographic adsorbents.
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Visualisering och beräkning av hudkapillärer / Skin Capillary Ensemble Visualisation and ComputationFredriksson, Ingemar January 2004 (has links)
The aim of this thesis was to develop an objective and automatic method for identifying capillaries in microscope images of the skin. Furthermore, statistical data about the identified capillaries and the capillary distribution should be computed and stored in a database. The method was implemented using the platform independent programming language Java. An analysis of microscope improvement using various polarization filter setups and wavelength filtershas also been performed, as well as a pilot study of the effect of applying a local anaesthetic cream on the skin. The method is developed and aimed at research on various pathological skin conditions affecting the capillary distribution. Hypertension, diabetes, inflammation, ischemia, connective tissue disease, and erythromelalgia are all examples of diseases or pathological conditions which are supposed to affect the distribution of the skin capillaries.
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Blinkbeteendebaserad trötthetsdetektering : metodutveckling och validering / Blink behaviour based drowsiness detection : method development and validationSvensson, Ulrika January 2004 (has links)
Electrooculogram (EOG) data was used to develop, adjust and validate a method for drowsiness detection in drivers. The drowsiness detection was based on changes in blink behaviour and classification was made on a four graded scale. The purpose was to detect early signs of drowsiness in order to warn a driver. MATLAB was used for implementation. For adjustment and validatation, two different reference measures were used; driver reported ratings of drowsiness and an electroencephalogram (EEG) based scoring scale. A correspondence of 70 % was obtained between the program and the self ratings and 56 % between the program and the EEG based scoring scale. The results show a possibility to detect drowsiness by analyzing blink behaviour changes, but that inter-individual differences need to be considered. It is also difficult to find a comparable reference measure. The comparability of the blink based scale and the EEG based scale needs further investigation.
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Fel och felkällor vid bäckenmätning / Error and sources of errors in radiological pelvimetryLarsson, Karin January 2004 (has links)
Syftet med detta arbete var att utreda felkällor som förekommer vid användning av olika tekniker/modaliteter vid bäckenmätning. Då det finns risker med röntgenstrålning önskar man reducera stråldosen vid undersökningarna samtidigt som man vill använda sig av en enkel metod. De olika modaliteterna som jämförs är i) direktdigital detektor och bildplatta, ii) bildförstärkarteknikteknik, iii) CT. Den modalitet man använder sig av idag är direktdigital detektor och bildplatta. För att korrigera för förstoring som uppkommer vid röntgenundersökningen placeras en mätsticka i bildfältet. Om mätstickan vinklas mot sagittalplanet blir korrigeringen fel och detta visas i teori och praktiska försök. Bildförstärkare kan användas för att ta sidobilden. Bildförstärkarens geometriska egenskaper ger dessvärre en måttdistorsion så att objekt i det perifera bildfältet blir förstorade mer än objekt centralt belägna. Det har inte framkommit något bra sätt att korrigera för distorsionen. CT har inte använts vid bäckenmätningar på Helsingborgs lasarett tidigare. Att använda topogrammet vid CT- undersökning kan även det vara behäftat med längddistorsion och förslag ges hur man kan korrigera för felet. I CT-snittbilder fås ingen längddistorsion.
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