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Multiple Antenna Terminals in Realistic Environments - A Composite Channel Modeling Approach

For evaluation of specific antenna arrangements in wireless communication systems we need physical channel models that take into account also the directional domain of the propagation channel. In this thesis we investigate, validate and propose a practical approach to wireless channel modeling and, particularly, to mobile communication systems. For this we make the assumption that the channel can

Studies on Heparin Binding protein in bacterial infections

Infectious diseases remain a major health problem, where sepsis and other severe bacterial infections are common causes of morbidity and mortality, and are associated with high costs for the community. The importance of early and appropriate treatment of sepsis and severe bacterial infections has been underlined by many and since sepsis is more prevalent and has a higher mortality rate than for in

Physiological recovery from night-call duty - a field study of physicians

Abstract Physicians’ work on night-call entails long and stressful working hours with high demands and disrupted sleep. Incomplete recovery is considered to be the most important link between acute physiological stress reactions, shift work and chronic health effects. Mental and physiological activation naturally accompanies night-call duty, but the crucial issue, from a health perspective, is wh

Cerebellar pathways and mechanisms in classical conditioning

It has been suggested that the cerebellar mossy fibre afferents transmit the conditioned stimulus (CS) information to the cerebellum. Several studies are consistent with this suggestion but alternative explanations have not been excluded. In conditioned ferrets, the forelimb CS was replaced by a direct stimulation of the cerebellar mossy fibre afferents. It was found that true conditioned response

Bilder av Förintelsen. Mening, minne, kompromettering

This thesis examines the representation in visual culture of the Holocaust, the Nazi genocide of European Jewry. It is divided into three main parts, each one focusing on a particular aspect of Holocaust representation. Part 1, "Meaning" (chapter 1-3), begins by considering the important role played by documentary photographs from the concentration camps for the public knowledge and conception of

Structure, evolution and expression of glandular kallikrein genes

Prostate-specific antigen (PSA) is a worldwide used tool for the diagnosis and monitoring of prostate cancer. It is a serine protease and belongs to the family of glandular kallikreins. Humans have three classical glandular kallikreins, but it has been reported that rodents have many more. Lately, the family has been expanded to contain 12 new genes, KLK4–KLK15, that are situated at the same locus

Calcium channel activity and force regulation in smooth muscle: Effects of polyamines and growth stimulation.

The initial signal for contraction in smooth muscle is an increase in [Ca2+]i. Ca2+ ions can either enter the cytosol from the extracellular medium or be released from intracellular stores. Voltage-operated Ca2+ channels (VOC) play a dominant role in the activation of smooth muscle contraction. This thesis describes two novel regulatory mechanisms of the dihydropyridine (DHP)-sensitive VOC in smoo

Interplay between superantigens and immunoreceptors

This thesis deals with the interactions between superantigens and their receptors. Superantigens are proteins that are secreted by various bacteria, such as Staphylococcus aureus and Streptococcus pyogenes. Superantigens are able to cross-link T cells and antigen presenting cells by binding to the T cell receptor (TCR) and MHC class II. They bind as unprocessed antigens and activate up to 20 % of

Prognostic factors in squamous cell carcinoma of the head and neck, with emphasis on 11q13 rearrangements and cyclin D1 overexpression.

At present, clinical outcome or response to therapy can not be fully predicted in individual cases of squamous cell carcinoma of the head and neck (SCCHN). The overall aim of the present studies was to investigate potential prognostic factors, more closely related to the malignant progression of a tumor than the established markers, such as the TNM-classification system. Tumor samples were investi

Neuropeptide Y - aspects of vasomotorresponses and receptor characterization

Abstract The aims of the present thesis were to examine neuropeptide Y (NPY) responses in different human and guinea pig vascular beds and in cultured human vascular smooth muscle cells (VSMC) and to characterize, with different NPY agonists and the specific NPY Y1 receptor antagonist (BIBP3226), the NPY receptors involved. NPY-induced strong and potent contractions in human cerebral and subcutan

Phenotypic modulation of vascular smooth muscle in organ culture

Contraction of blood vessels for the regulation of blood flow and pressure is dependent on vascular smooth muscle cells (VSMC) located in the medial layer of the vascular wall. Adult, differentiated VSMC have a well developed contractile system and a low rate of proliferation. Under the influence of hormones, growth factors, inflammatory mediators and tissue factors, cells may modulate to a ”synth

PACAP and orphanin FQ/nociceptin -Distribution, importance and regulation in sensory neurons and spinal cord

Neuropeptide expression in the nervous system is abundant and plastic, and an altered expression after injury is an example of a functional response, helping the neuron to cope with adverse changes, and involves effects on differentiation, synthesis, repair/regeneration, survival, and modulation of signal transmission. I have investigated the distribution/expression of the neuropeptides, orphanin

Effects of Rho kinase, prostacyclin and L-arginine on microvascular permeability and perfusion

This thesis presents some effects of Rho kinase, prostacyclin (PGI2) and nitric oxide (NO) in relation to trauma and inflammation by evaluating their effects on microvascular perfusion and permeability in mouse brain and in cat skeletal muscle. PGI2 and NO are endogenous vasoactive substances produced by the endothelium. They are vasodilators with antiaggregatory/antiadhesive and permeability-redu

Hormonal regulation of phosphodiesterase 3B in adipocytes

Insulin induced activation of the cAMP degrading enzyme phosphodiesterase (PDE) 3B in adipocytes is important for insulin mediated inhibition of lipolysis. The aim of this thesis was to contribute with knowledge on the acute activation of PDE3B in response to insulin and catecholamines in adipocytes. The activation of PDE3B was investigated from three different perspectives namely; phosphorylation

Ultrasonic Methods for 2D Arterial Wall Movement Measurements

Cardiovascular diseases constitute the major cause of morbidity and mortality in the Western World. To increase our knowledge of cardiovascular diseases, it is important to find methods, preferably non-invasive ones, to study very early manifestations of vascular disease. Changes in the mechanical properties of the arteries can be an early manifestation of vascular disease. Further, changes in the

Phosphor Thermometry on Surfaces - A Study of its Methodology and its Practical Applications

Phosphor Thermometry is a term describing an optical measurement technique for remote temperature sensing. Its working principle is based on the temperature-sensitive emission characteristics of certain ceramic substances termed thermographic phosphors. These inorganic materials can either be coated on objects for surface thermometry or be seeded into the gas phase or into liquid flows as solid pa

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Popular Abstract in French Certaines recherches ont suggéré une différence entre l’acquisition d’une première langue (L1) et celle d’une langue seconde (L2) à l’âge adulte. L’une des questions débattues dans ce domaine est de savoir quand et pourquoi s’arrête l’acquisition du type L1 et quand commence l’acquisition du type L2 adulte. Dans ce débat, un troisième mode d’acquisition, enfant L2 ou bil