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Din sökning på "swedish" gav 92287 sökträffar

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

Early events in T cell development

T cells constitute a heterogenous population of lymphocytes. Their unifying property is that they express surface bound antigen-receptors, called T cell receptors (TCRs). The TCR is a heterodimer composed of either TCRalpha and beta chain proteins (alphabeta TCR) or gamma and delta chain proteins (gammadelta TCR). Depending on which TCR isotype that is expressed, the T cells are divided into alpha

Mechanistic investigation of platinum and palladium catalysed cross- coupling reactions. Implications for the Stille and Heck reactions.

The present thesis deals with various types of palladium(II) and platinum(II) complexes and their use in homogeneous catalysis. The focus has been devoted to mechanistic investigations concerning the Stille and Heck reactions and studies under both catalytic and stoichiometric conditions were conducted. As a stoichiometric probe for studying the transmetallation step in the Stille reaction the pl

Ecological and evolutionary assembly processes and metacommunity structure

This thesis aims to elucidate the link between abiotic and biotic effects and biogeographical contingencies, eco-evolutionary assembly processes, and community structure in a spatially explicit metacommunity framework. To this end, we used structure analysis of naturally sampled and experimentally manipulated marine bacterial communities and mathematical eco-evolutionary modeling and simulations o

Artifacts and Supraphysical Worlds : A Conceptual Analysis of Religion

It is a contested question in contemporary theories of religion whether the concept of religion can be defined in a sound way or not. Many theorists maintain that a universal but delimiting definition is impossible. In this study, by contrast, it is argued that a conceptual analysis of religion that holds universally is perfectly possible because the following thesis can be seen as a necessary and

Spontaneous Movements during Sleep Guide Spinal Self-organization: Formation and Expression of a Memory Trace

During development, information about the three-dimensional shape and mechanical properties of the body is laid down in the synaptic connectivity of sensorimotor systems through adaptive mechanisms. In spinal reflex systems, this enables the fast transformation of complex sensory information into adequate correction of movements. In this thesis, it is shown, in a computer simulation, that an unsup

Aspects of sepsis/SIRS - An experimental study on fluid therapy, vitamin C and plasma volume in increased permeability

In sepsis, after major surgery or severe trauma, the human body may suffer from various degrees of generalized inflammation, a syndrome called Systemic Inflammatory Response Syndrome (SIRS). One feature of SIRS is increased capillary permeability, caused by disruption of the capillary endothelium due to e.g. bacterial toxins, cytokines, pro-inflammatory hormones and free oxygen radicals. This will

Reproductive function in male childhood cancer survivors

Childhood cancer (CC) survival rate has increased over the last couple of decades, today approaching 80%. Therefore more attention has been paid to late effects. One important issue for CC survivors (CCS) is impaired reproductive function. CC per se and/or its treatment can impair the reproductive ability by affecting sperm production, as well as by damaging sperm DNA. This is a matter of concern,

ULTRASOUND STUDIES ON PELVIC FLOOR PHYSIOLOGY AND OBSTETRIC PERINEAL TEARS

Repair of obstetric perineal tears is one of the most frequent procedures in surgical practice. Despite repair such tears may result in anal and urinary incontinence and prolapses of the pelvic floor, problems in need of surgical repair later in life. Descriptions of the structures injured during vaginal delivery and their topographic relations in the perineum are missing in most textbooks. Trans

The HCCI Engine – High Load Performance and Control Aspects

Current combustion engines provide excellent performance for vehicle propulsion and power generation. However, recent demands from society ask for higher efficiencies and lower emissions. These requirements are hard to meet with current technology and call for new solutions. Homogeneous Charge Compression Ignition, HCCI, offers a potential to combine high efficiency with very low emissions. It op

ADAMTS13 phenotype in health and disease with special reference to thrombotic thrombocytopenic purpura

Von Willebrand factor (VWF) is synthesized and secreted by endothelial cells into the plasma as a series of multimers. VWF induces the formation of platelet plugs at sites of vascular injury and high shear stress. Biological activity is dependent on multimeric size, which is regulated in plasma by the VWF-cleaving protease ADAMTS13. Severe ADAMTS13 deficiency is associated with thrombotic thromboc

Applications of Bayesian Econometrics to Financial Economics

This PhD thesis consists of four separate papers. What these papers have in common is that Bayesian Econometrics, in combination with Markov chain Monte Carlo (MCMC) methods, is applied to study various problems in financial economics. The first two papers are further related in that they both deal with portfolio selection and estimation risk, as are the last two papers in that they both deal with

Psychosomatic aspects on diabetes and chronic pain Alexithymia, depression and salivary cortisol The Affect School and Script Analysis Therapy

This thesis explores links between psyche and soma in diabetes and in chronic benign pain (CBP). Interventions with Affect School and Script Analysis (ASSA) compared to Basic Body Awareness Therapy (BBAT) are tried. In a feasibility and treatment efficacy study we offered ASSA to 59 patients with CBP, and 54 (92%) completed. Alexithymia prevalence went from 33% to 11% (p = 0.013), depression from

Roles of protein kinase C in cell death and breast cancer

Aberrant protein kinase C (PKC) activity and expression is implicated in different malignancies. To study the role of different PKC isoforms in breast cancer the expression of PCKα, δ and ε was evaluated in breast cancer tumors. In addition the effect of siRNA-mediated knockdown of the isoforms was studied in a global gene expression analysis. We found that high PKCα levels correlate with poor pro

Schooling Emotional Intelligence Through Narrative and Dialogue. Implications for the education of children and adolescents

Abstract The point of departure for this study is the author's experience as educator in a residential home for children (age 6-14) with social-emotional problems, in Italy, between 1980 and 1989. One important element of the pedagogical approach was the use of narratives (personal, of others, of fiction) to prompt children's interest/ motivation to reflect about issues of personal concern. A conv

Women, smoking and myocardial infarction

The aim of this thesis has been to explore factors associated with smoking and smoking cessation in women and the relation between smoking and incidence of myocardial infarction (MI). The time trends in incidence of MI 1986-2002 in the city of Malmö (pop. 250.000) were explored. It showed declining incidences in men and older women, but not in women below 65 years of age. The high prevalence of s