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In order to understand the formation and evolution of the Galaxy it is imperative to know when different components formed. This means at the most basic level that we need to know the ages of stars. The present work demonstrates the many problems inherent in determining the ages of stars through comparison with stellar evolutionary models. Furthermore, solutions to some of these problems are prese

Turbine-agitated tanks are used in chemical and biochemical applications to increase mixing which, in turn, affects the yield, productivity and product quality. The purpose of this work was to study the hydrodynamic influence on the scale-up of turbine-agitated tanks, commonly used in fermentation. Local turbulent flow parameters, the turbulent kinetic energy and the local energy dissipation rate,

The work in this thesis has been focused on chondrocyte integrins and their interaction with the matrix proteins chondroadherin (CHAD) and collagen type II (CII). Affinity purification of CHAD-binding proteins from chondrocyte lysate, followed by immunoprecipitation of EDTA-eluted material identified alpha2beta1 as a CHAD-binding integrin. Interaction between alpha2beta1 and CHAD was found to prev

This thesis introduces and summarizes four papers dealing with computer simulations of astrophysical processes involving binaries. The first part gives the rational and theoretical background to these papers. In paper I and II a statistical approach to studying eclipsing binaries is described. By using population synthesis models for binaries the probabilities for eclipses are calculated for diff

The amino acid glutamate is today regarded as the main fast excitatory neurotransmitter in the central nervous system and a large body of evidence support that glutamate serves as a neurotransmitter in primary afferent terminals in the spinal cord. Previous evidence also suggests that the closely related amino acid aspartate may serve a similar role in some primary afferent terminals. However, the

This study examines safety and fear of crime in Åboland, a predominantly rural area in southwestern Finland. It also examines crime and criminals in the area, as well as the distinctive social control that characterises Åboland's eight municipalities. The study continues two strands of research, the first about criminality and fear of crime in societies that are considered safe by their inhabitant

Fine-grained soils are often regarded as problematic soils in earthworks because of their water- and frost sensitivity. Only limited amounts of fine-grained tills are used as earthwork material today. The main objective of this thesis is to improve the knowledge of how to use and also treat a fine-grained till, so that a greater amount can be utilised as earthwork material. To achieve an increasin

In an 18-month period all throat cultures in our laboratory were examined for Arcanobacterium haemolyticum and clinical information was obtained. The great majority of the patients suffered from pharyngitis or tonsillitis, accompanied by a rash in 46% of cases. One third of the patients had a history of recurrent tonsillitis. Three types of exanthema was described, scarlatiniform, urticarial and e

The molecular process under which message in DNA is relayed onto RNA is called transcription, and it accomplished through involvement of so-called transcription factors. Zinc finger proteins are one of the most abundant classes of regulatory proteins in eukaryotic cells where they play central roles in a variety of cellular activities. A classical zinc finger is a small protein motif with a simple

There are many examples of complex networks in science. It can be genetic regulation in living cells, computers on the Internet, or social and economic networks. In this context, Boolean networks provide simplistic models that are relatively easy to handle using computer simulations and mathematical methods. A good understanding of Boolean networks may form a foundation to investigations of more c

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

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

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 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

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

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 (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