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In this thesis, I have studied nitrogen turnover processes in watermeadows. A watermeadow is a wetland where water infiltrates through the soil of a grassland field. It is hypothesized that infiltration of water through the soil matrix promotes nutrient transformations compared to surface flow of water, by increasing the contact between water, nutrients, soil organic matter and bacteria. I have st

This thesis consists of three self-contained empirical studies on international financial economics. The common economic theme is that all three studies deal with international stock market return and risk. The common econometric theme is that all estimations are performed using simulated annealing, a stochastic optimization algorithm in the Markov Chain Monte Carlo family, in an attempt to solve

The planning and design of street networks in cities influence driving behaviour and give rise to variations in driving patterns (i.e., speed and acceleration profiles) that affect exhaust emissions and fuel consumption. The primary objective of this study has been to use real-life driving patterns to investigate how the characteristics of street networks influence fuel consumption and vehicular e

Local anaesthetics provide excellent pain relief after central and peripheral nerve blocks. However, in many clinical situations there is an insufficient duration of action to allow effective treatment of long-term pain with single injection techniques. This problem became the focus of the present studies. The natives in South America used to chew the leaves from Erythroxylon Coca and were well aw

Ischemic brain damage is a common cause of death and disability. A global ischemic insult is usually the result of a transient cardiac arrest while occlusion of cerebral blood vessels leads to focal ischemic lesions, commonly termed stroke. During the last decades our knowledge about the metabolic and cellular events leading to cell death following ischemia has expanded mainly due to experimental

Ex-smokers are exposed to a higher breast cancer risk than are never smokers. This conclusion is based on a follow-up of the 10 902 women in the Malmö Preventive Project. The 31% higher incidence in ex-smokers remained statistically significant when other risk factors were taken into account in the analysis. In both smokers and ex-smokers there was an increased incidence of oestrogen receptor nega

In the present thesis, genetic abnormalities in pancreatic cancer were studied, with special emphasis on alterations of components involved in the transforming growth factor beta (TGFB) signaling pathway. In the first study, fluorescence in situ hybridization and cytogenetic analyses revealed aberrations of chromosome 18 in all 13 pancreatic carcinoma cell lines studied, in particular frequent bre

Corticosteroids are anti-inflammatory and anti-proliferative substances that also can induce sensitization, mainly through skin contact. In a sensitized individual, it can be hard to disclose the contact allergy at patch testing because the anti-inflammatory effect may mask the allergic contact reaction. This is primarily seen when patch testing to potent corticosteroids is performed and the readi

Acute myocardial infarction (MI) and deep venous thrombosis (DVT) are conditions caused by thrombus formation with activation of the coagulation system. The plasma concentration of the complex between activated protein C (APC) and protein C inhibitor (PCI), APC–PCI complex is increased in such states. We have devised an immunofluorometric assay employing a catcher antibody (M36) that recognizes a

Treating the correlated behaviour of multiple particles is challenging for both theory and experiment. This thesis reports on a variety of experimental investigations aiming to advance the understanding of fundamental processes in atoms and molecules: double ionization, isomerization and dissociation. The emphasis lies on ultra-fast processes, where multiple electrons interact or nuclei move so ra

Complexes formed between oppositely charged polyions and surfactant ions are known to have very rich phase behaviour in bulk solution. The work in this thesis investigates the possibilites of using such complexes as surface coatings. Stoichiometric polyion-surfactant ion complexes “complex salts” (CS) consisting of alkyltrimethylammonium surfactant ions and polyacrylates are typically insoluble i

A modular organization has recently been described for the cerebellar control system comprising the forelimb areas of the C1/C3/Y zones in the cerebellar cortex and nucleus interpositus anterior (NIA) of the cat. A module is a group of cells in NIA which receives homogenous climbing fibre input via Purkinje cells that belong to the same set of microzones in the C1/C3/Y zones. The organization of i

RNA molecules in the cellular environment have several important functions. In many cases, proper RNA function is intimately linked to proper three-dimensional structure of the molecule. Thus, it seems reasonable to assume that structural changes caused by external influence can strongly inhibit important cellular functions maintained by RNAs. Studies in this thesis have had a focus on the influen

Streptococcus pyogenes causes infections only in humans, from trivial tonsillitis to life-threatening conditions. One of its most important virulence factors is the M-like protein family conferring resistance to phagocytosis to the bacterium. The M-like proteins are surface exposed rod-like molecules attached to the cell wall. Each strain of S. pyogenes expresses unique M-like proteins that bind t

Lectins defined as non-enzyme, non-immunoglobulin carbohydrate binding proteins, have been found in a wide variety of viruses, bacteria, fungi, plants and animals. Although lectins have been purified from more than 60 different species of fungi, the structure and biological functions of these proteins are not well known. I examined the molecular structure of a lectin (designated AOL) isolated from

In vertebrates the Major Histocompatibility Complex (MHC) plays a central role in the specific immune defence against various pathogens. Compared with other coding genes the MHC genes exhibit an extremely high level of polymorphism that is maintained by balancing selection. The importance in the immune defence and the polymorphism make these genes interesting to study from an ecological and evolut

Suicide in Severe Depression. A Longitudinal Case-Control Study. The present thesis is based on a case-control study of suicide victims with a severe depression/ melancholia. All patients admitted to the Department of Psychiatry 1956-1969 who received this diagnosis on a multiaxial schedule (1206 patients) were followed up in two sessions to 1984 and to 1998 concerning suicide and general mortali