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Electron Transport in Nanowire Quantum Devices

This thesis focuses on electron transport in semiconductor InAs/InP and InSb nanowire quantum devices. However, first the temperature dependence of classical charge transport in InSb nanowire field-effect transistors, FETs, is characterized, using InAs nanowire FETs as a reference. We find that the InSb FETs, in the same way as InAs FETs, are n-type with good current saturation and low voltage ope

S100B and Cardiac Surgery

The brain-derived protein S100B is a 21 Kda dimerand have been used as a serum marker for brain damage of different etiology. The feasability of protein S100B as serum marker for brain damage after cardiac surgery was studied in this thesis. One unexpected finding was made, which changed the basis for interpration of S100B levels. Shed blood collected during surgery with cardiotomy suction contain

Realism in metacognitive judgments : Effects of social factors

Theoretical accounts and models of calibration typically explain the degree of realism (validity) in confidence and frequency judgments in terms of different cognitive and methodological factors. The present thesis demonstrates that also social factors are of importance for the degree of realism in these types of metacognitive judgments. The results of Study I showed improved realism in pairs’ con

On the regulation and effects of chronic inflammation in inflammatory bowel disease

Inflammatory bowel disease is thought to result from the inappropriate and ongoing activation of the mucosal immune system driven by the presence of normal luminal flora. In this process monocytes/macrophages contribute to and maintain chronic inflammation by being both regulatory and effector cells. This study aimed at exploring the effects and regulation of chronic inflammation in inflammatory

Human fetal cerebral circulation - Perinatal Doppler velocimetry and fetal pulse oximetry studies

The studies upon which this thesis is based were designed to evaluate normal fetal and neonatal adaptation and the effects of obstetrical interventions during labor and delivery on fetal and neonatal cerebral circulation. Non-invasive Doppler ultrasound was used to record blood flow velocities from the middle cerebral artery (MCA) both antenatally from the fetus, and from the newborn in the early

Sparse Modeling Heuristics for Parameter Estimation - Applications in Statistical Signal Processing

This thesis examines sparse statistical modeling on a range of applications in audio modeling, audio localizations, DNA sequencing, and spectroscopy. In the examined cases, the resulting estimation problems are computationally cumbersome, both as one often suffers from a lack of model order knowledge for this form of problems, but also due to the high dimensionality of the parameter spaces, which

The Formation of Giant Planets

Giant planets form embedded in a protoplanetary disc around a young star. Close to the midplane a large fraction of the available mass in solids is found in particles of cm to dm in size, which drift towards the star due to friction with the surrounding gas. In paper I, II, III we describe a novel theory that explains how embryos, planetesimals larger than ~1000 km, grow efficiently by sweeping up

Mechanisms of survival and maintenance of Hematopoietic Stem Cells and Multipotent Progenitor Cells

Hematopoietic stem cells and progenitor cells are maintained in the bone marrow microenvironment, where factors including soluble and membrane-bound cytokines influence the processes of self-renewal, proliferation and differentiation. Two nonreduntant cytokines with effects on hematopoiesis, Kit Ligand (KL) and Flt3 Ligand (FL), signal via related tyrosine kinase receptors, c-kit and Flt3. In this

Effects of dietary fibre on the human metabolism and metabolome

It is well-known that dietary fibre can have a positive effect on the development of lifestyle-dependent diseases such as cardiovascular disease and type 2 diabetes. However, the effect may be different for different kinds of fibre and different sub-populations at risk. Therefore, the effects of three different kinds of fibre on postprandial and long-term response in healthy subjects were investig

Investigation of a Biofilm Reactor Model with Suspended Biomass

Biofilms are compact, sessile microbial communities that attach to surfaces in aqueous environments. In wastewater treatment, they are especially important for removal of phosphorus and nitrogen, which, if released into a receiving water body, can cause severe eutrophication. Mathematical models of biofilms in wastewater are used to understand the underlying processes and to describe and analyze b

High Repetition Rate Laser Diagnostics for Combustion Applications

High repetition rate laser diagnostics has proven to be a useful tool for studying combustion phenomena. Laser techniques are, in general, relatively non-intrusive and have the potential to measure specific species at very low concentrations and with extremely high temporal resolution. However, most laser systems in this field of research are limited to repetition rates below 100 Hz, and are thus

Chromoendoscopy with particular reference to a modified endoscopic Congo red test

Chromoendoscopy, endoscopic tissue staining, is an adjunctive method using chemical agents applied to the mucosal surface in order to aid gastrointestinal endoscopic diagnosis and therapy. Acid producing mucosa in the GI tract may be visualized endoscopically by Congo red staining in combination with stimulation of gastric acid production. Congo red is a reactive indicator dye that changes color f

Improving Productivity and Enzyme Stability Through Process Design: Lipase-catalysed Synthesis of Epoxides and Esters

Interest in sustainable development has increased throughout society during the past decades, and the chemical industry is no exception. The appeal for renewable raw materials has consequently increased and has paved the way for the implementation of industrial biotechnology. Since enzymes are used to convert biomass in nature, they may also be a good choice in the chemical industry. However, to i

Plant community assembly during succession from arable fields to semi-natural grassland

Large areas of grazed, species rich semi-natural grassland were lost in Europe during the last two centuries and as a consequence led to decreases in grassland specialist species. Therefore, today the “restoration” of grassland on previously arable fields is recommended for the protection of grassland specialists. Even “substitute habitats” for lost grasslands are discussed as temporary alternativ

Renormalization in Effective Field Theory and Hidden Radiation

This thesis dealswith the field of high-energy particle physics. It ismainly concernedwith two issues: the “renormalization of effective field theories” and the “detection of hidden sectors”. The first two papers are dedicated to the renormalization issue while the second two deal with the hidden sectors. Renormalization is crucial when one calculates physical observables to a high degree of preci

Surface Modification of Biomedical Polyurethanes

The aim of the this thesis was surface modification of a biomedical polyurethane (PUR), Pellethane 2363-80AE*, to improve the biocompatibility. Surfaces modified by poly(ethylene oxide) (PEO) were prepared either by grafting PEO covalently at the PUR surface by a two-step reaction, or by using amphiphilic polymers containing PEO as the hydrophilic part. The amphiphilic polymers consisted of one co

Inducible nitric oxide synthase in experimental urinary tract infection

Urinary tract infection (UTI) is among the most common bacterial infections in humans and the majority are caused by Escherichia coli (E. coli). Abundant evidence indicates that nitric oxide (NO) produced by the inducible NO synthase (iNOS) plays an important role in host defense against infection. This thesis examines iNOS expression in experimental UTI models. The rat and pig bladder urothelium

Inhibitors of Human and Malaria Parasite Dihydroorotate Dehydrogenase

In the first part of the PhD work, small chemical entities (fragments) found to inhibit human dihydroorotate dehydrogenase (DHODH), were chemically optimized. As part of an ample program at Active Biotech to find new drugs against autoimmune diseases, expanded fragments were repeatedly designed, synthesized and evaluated in a human DHODH assay. Potent inhibitors were identified within three classe

Rate Limiting Factors For Protein Folding.

Abstract. This thesis describes factors that are rate limiting for the folding of two small proteins, U1A and CI2 which fold without accumulating intermediates. The [GdnHCl] dependencies of the unfolding- and refolding kinetics of U1A display downward curvatures. However, as the curvatures are precisely matched and no indications of formation of partially structured intermediates are seen, the fol

Protein Microarrays Based on Single Framework Recombinant Antibody Fragments (SINFABS) - Catcher and Carrier - A Crucial Combination

Antibody-based microarrays are among the novel class of rapidly evolving proteomic technologies. In recent years, antibody microarrays have emerged as a unique tool for high-throughput protein expression profiling with great promise within biomedicine and a wide range of potential applications, including disease diagnostics and biomarker discovery. In order to evolve the technology from small dedi