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Din sökning på "swedish" gav 92291 sökträffar

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

A Molecular Dissection of Mantle Cell Lymphoma - From gene expression analysis to functional evaluation of selected targets

Mantle cell lymphoma (MCL) is an aggressive form of B-cell lymphoma (BCL) with poor clinical outcome. In this thesis, which is based upon five original papers, different approaches have been used to pinpoint and investigate molecular events that promote MCL tumor growth, progression or resistance to treatment. The aim has been to identify novel targets with the potential to eradicate malignant cel

Role of TLR4 in Escherichia coli urinary tract infection

In this thesis we have used P fimbriated E. coli as a model to investigate the mechanisms of bacterial recognition and cell activation by the urinary tract (UT) epithelium. We show that Toll like receptor 4 (TLR4) is crucial for the recognition and host response to P fimbriated E. coli. This response was independent of LPS and did not require CD14. TLR4 was abundant on epithelial cells throughout

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

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

Thyroid hormones and breast cancer-prospective studies on incidence, mortality and prognostic factors

Thyroid hormones and breast cancer-prospective studies on incidence, mortality and prognostic factors The aim of this thesis was to investigate in a prospective design, thyroid hormones in relation to breast cancer risk, mortality and prognostic factors. The association between total triiodothyronine (T3) levels and breast cancer risk was studied in 2185 women with146 incident breast cancer case

RNA in model lipid membranes - interactions in bulk and at surfaces

The work presented in the thesis “RNA in model lipid membranes- interactions in bulk and at surfaces” aims to characterize the interaction between RNA and model membranes with different properties as well as to determine if ssRNA associate with model membranes in different ways. Several techniques have been used to characterize these systems, including quartz crystal microbalance with dissipation

High-Frequency ECG in Ischemic Heart Disease

Analysis of high-frequency QRS components (HF-QRS) is one of the emerging methods for increasing the diagnostic performance of the electrocardiogram (ECG). The overall objective of the thesis is to investigate whether analysis of HF-QRS has the ability to provide information about ischemic heart disease and so serve as an adjunctive diagnostic tool in several clinical situations. Investigation of

Body Protein and its Change in Patients During Anti-Tumor Treatment

The purpose of this study was to investigate how total body protein and its fraction of body weight (body protein fraction) change in cancer patients during different anti-tumor treatments, and to see if these changes have any clinical significance in the form of prognostic value or correlation with disease course and tumor response. In 84 patients, 28 with lung cancer, 24 with gastrointestinal t

Arkitekturens kroppslighet. Staden som terräng

Beginning with the notion that spatial and material qualities of architecture set limits and create conditions for how we make use of it, the overall aim and ambition of this thesis is to develop this notion and to contribute to a deeper understanding of the relationships that are produced between the materiality of architecture and a bodily appropriation of it. To investigate this the thesis esta

The telomere binding proteins in yeast and their role in telomere maintenance

Telomeres are the end-structures of linear chromosome which are crucial for maintaining genome integrity. The telomeres prevent the DNA-repair machinery from recognizing the chromosome ends as double-strand breaks and from end-to-end fusions. The telomeres are composed by short repetitive units of TG-rich DNA and associated specialized telomere-binding proteins. Due to that replication only can

Vasodilator actions of EDHF and anandamide

Vasodilator responses to endothelium-derived hyperpolarizing factor (EDHF) and anandamide in isolated arteries were investigated. A combination of the potassium channel blockers charybdotoxin and apamin inhibits EDHF-mediated relaxations. Experiments in which charybdotoxin or apamin was substituted with other potassium channel inhibitors indicated that small- and intermediate-conductance calcium-a

Respiratory Sinus Arrhythmia and Emotion : Effects of pictorial stimuli and state anxiety

Respiratory sinus arrhythmia (RSA) refers to heart rate variations due to respiration, which results from parasympathetic nervous system activity mediated via the tenth cranial nerve, the vagus. Thus, the magnitude of RSA is considered as an index of cardiac vagal tone. This thesis explored RSA during emotional responding in healthy women and men. In the first two studies fear-relevant pictorial s

Synergistic interactions involving amphiphilic polymers in solution

The properties of hydrophobically modified cellulose derivatives in aqueous mixtures with various other molecules have been investigated. Mixtures of a hydrophobically modified polymer and alkali-sensitive, degradable surfactants gave rise to time-dependent viscosities. With time, the viscosity decreased continuously or went through a maximum, depending on the initial surfactant concentration. Th