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Electrical Studies of Quantum Devices

This thesis deals with electrical measurements on quantum devices. The thesis is divided into three major areas: electrical characterization, semiconductor devices, and metal devices. The electrical characterization part present problems and advantages with the measurement techniques used in the the thesis, .i.e., Current-Voltage; Conductance, including higher order harmonics; Capacitance; Cross-

The Gastrin-ECL Cell Axis. Functional Aspects

The ECL cells constitute a prominent endocrine cell population in the acid-producing part of the stomach. They are controlled by circulating gastrin released from G-cells in the antrum. In response to gastrin, they secrete histamine, that in turn stimulates the parietal cell to secrete acid. The first aim of the study was to prepare isolated ECL cells of high purity and to study and identify regul

Foam Formation and Starch Gelatinization with Alpha-Crystalline Emulsifiers

In the baking industry, emulsifiers in the alpha-gel state are used for foam formation. This thesis focuses on some parts of the effects of the emulsifier: how the foam formation and foam stability are influenced by the physical state of the emulsifier, how emulsifiers change the gelatinization and gel formation of starch, and the impact that these factors may have in a true product such as a spon

Physiology of Caldicellulosiruptor saccharolyticus: a hydrogen cell factory

A high substrate conversion efficiency is a prerequisite for an economically feasible biohydrogen production. Caldicellulosiruptor saccharolyticus is a strictly anaerobic extreme thermophilic bacterium that is able to convert the theoretical maximum of 4 mol/mol glucose to H2. It can grow and produce H2 on a broad spectrum of sugars ranging from monomers (hexoses and pentoses) to more complex suga

Development of Methods for Determination of Fat and Trace Constituents in Food, with Emphasis on Supercritical Fluid Extraction

Sample preparation is the most time-consuming step in an analysis. Traditional sample preparation techniques consume large amounts of organic solvents, are time-consuming and are difficult to automate. During the last decade some new extraction techniques have been developed for sample preparation and one of them is supercritical fluid extraction (SFE). This thesis focuses on sample preparation fo

The Late etruscan votive heads from Tessennano. A study of production, distribution and sociohistorical context.

The Late etruscan terracotta votive heads from Tessennano were found near a rural sanctuary about a hundred km to the North of Rome in 1956. Whereas the facial fronts are serially produced with moulds, the backs are handmade. By using not only the moulded and the handmade features but the raw material (clay and temper) as well, it has been possible to make suggestions as to how, when and where the

A Methodology to Control the Microstructure of Plasma Sprayed Coatings

The aim of this thesis is to enhance the overall understanding of the plasma spray process and increase control and reproducibility of the coating properties. This was performed by establishment of relationships between controllable process parameters, in-flight properties of the injected particles (velocity and temperature), and microstructure properties. The relationships were used to establish

Nucleic Acids as Drug Targets - Influence of Platinum Complexes on Duplex Stability and Binding Kinetics

Gaining a detailed understanding of how human cells are affected by metal-based drugs is crucial, since these drugs have shown great potential in cancer treatment. Cisplatin is used to treat many different types of cancer, e.g. testicular, ovarian, melanoma, bladder, non-small cell lung cancer, small cell lung cancer, myelomas and lymphomas. The miRNA expression profiles in different human cancers

Contrast-Enhanced Magnetic Resonance Angiography - Development and optimization of techniques for paramagnetic and hyperpolarized contrast media

Contrast-enhanced magnetic resonance angiography (CE-MRA) is a diagnostic method for imaging of vascular structures based on nuclear magnetic resonance. Vascular enhancement is achieved by injection of a contrast medium (CM). Studies were performed using two different types of CM: conventional paramagnetic CM, and a new type of CM based on hyperpolarized (HP) nuclei. The effects of varying CM con

Upplysningens självreflexion : Aspekter av Theodor W. Adornos kritiska teori

This dissertation consists of a collection of previously published or otherwise presented essays dealing with the philosophical, sociological and aesthetic writings of Theodor W. Adorno (1903-1969). The title of the dissertation is intended to cover a common programmatic theme running through Adorno's writings. Chapter one, ?Adorno and the Frankfurt school?, deals with the biography of Adorno and

Cleaning of ultra-high temperature milk fouling -Structural and compositionl changes

Fouling is the deposit of proteins and minerals formed on equipment surfaces during the heat treatment of dairy products. The concentrations of the components and the structure of the fouling reflect the processing conditions used. The use of a higher processing temperature, e.g., ultra-high temperature (UHT) treatment, promotes a mineral-rich fouling. The fouling layer decreases the transfer of h

Vitreoscilla Haemoglobin - Peroxidase Activity and Metabolic Aspects

The function of non-vertebrate haemoglobins (Hbs) appears more diverse than that of vertebrate Hbs, possibly reflecting the various demands to be met among their hosts. Sharing structural features with other haem proteins/enzymes, Hbs display a qualitative overlap in activities with functions extending beyond oxygen transport/storage. When subjected to oxygen deficient conditions, the obligate ae

Social psychological barriers to a gender balanced labor market : The role of gender identity threats, friendship priorities, and perceived discrimination

Gender remains a key predictor of vocational choice. The present thesis aimed to investigate three social psychological barriers to nontraditional career choice. Study Ӏ showed that threats to gender identity may lead to more gender-typical occupational preferences among adolescents. The results suggested a unique effect of gender identity threat, as a control threat did not have the same effect.

Impulse Response Identification Applied to Estimation of Event-Related Potentials and Non-Intrusive Echo Path Analysis

This thesis consists of five parts in which problems in two fields, medical and telecommunication, have been studied. In the first part, a prediction algorithm, the Prony method, for estimation of frequencies and damping factors of sinusiods is developed for a coloured noise disturbance. The method is applied to estimating a single Event-Related Potential, sERP, and the estimation principle is ev

A study of dedications to Aphrodite from Greek magistrates

Through the identification of a series of inscriptions, mainly datable to the Hellenistic era, a link between Aphrodite and the civic life and administration of the Greek poleis has come to light. The inscriptions in question are dedications to Aphrodite through which magistrates of various cities and varying status express their devotion to the goddess. In certain dedications, the goddess is even

Amphiphilic Polymers as Additives in Biomedical Polyurethanes. Surface Properties and Morphology

The aim of this work was to achieve surface modification of two biomedical polyurethanes and one poly(urethane urea) through the addition of small amounts of amphiphilic copolymers in solution. The matrix polymers used were the poly(ether urethane)s Pellethane 2363-80AE (P80) and 2363-75D (P75) and a poly(ether urethane urea) similar to Biomer (PUUR). The amphiphilic additives consisted of segment

A clinical positron emission tomography facility : 2-¹⁸FDG studies : development and results

Positron emission tomography (PET) is a tracer technique used for quantitative in vivo studies of physiological and biochemical processes. Because of the use of positron-emitting radionuclides such as 11-C, 13-N, 15-O and 18-F, which are isotopes of the biologically ubiquitous elements, it is possible to label radiopharmaceuticals which trace biochemical processes precisely. In order to be able to

Quantitative assessment of myocardial infarction: On the relationship between anatomy and electrophysiology using MRI and ECG

Both presence and extent of myocardial infarction are important prognostic factors for mortality and quality of life in patients with ischemic heart disease. Thus, it is of great clinical importance to be able to diagnose and characterize myocardial infarction. One way to diagnose myocardial infarction is by using the 12-lead electrocardiogram(ECG). For estimation of infarct size and location from

Topics in Complex Analysis and Operator Theory I. The shift operator on spaces of vector-valued analytic functions II. Fatou-type theorems for general approximate identities III. Preduals of Q_p-spaces

This thesis consists of six articles on three different subjects in the area of complex analysis, operator theory and harmonic analysis. Part I - "The Shift Operator on Spaces of Vector-valued Analytic Functions" consists of three closely connected articles that investigate certain operators in the Cowen-Douglas class with spectrum D - the unit disc, or equivalently, the shift operator M_z

Perioperative regimens for patients undergoing elective hip or knee arthroplasties.

Background: Elective knee and hip arthroplasty are common surgical procedures. Improved anaesthetic and nutritional care has the potential of increasing patient satisfaction and reducing length of hospital stay (LOS). The overall aim of this thesis was to evaluate the effect of perioperative nutrition and different anaesthetic techniques on per- and postoperative outcome after elective total hip (