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Din sökning på "swedish" gav 91218 sökträffar

Solar Activity Changes at the End of the Last Ice Age - Influences on Climate and Applications for Dating

Throughout its history Earth experienced a variety of natural climate changes. By investigating their spatial and temporal evolution we can increase the understanding of the mechanisms and dynamics underlying natural climate change and improve our general comprehension of the climate system. Prerequisites of these investigations are reliable reconstructions of past forcing variations as well as so

FGF signaling in specification of hESC-derived definitive endoderm

Diabetes affects around 200 million people worldwide. Curing diabetes would require the prevention of autoimmune destruction of beta cells and restoration of the beta cell mass restored either through regeneration or transplantation of the insulin producing cells. Islet transplantation according to the Edmonton protocol have been the most promising therapeutic option for Diabetes type I patients,

Biological Functions of Iduronic Acid in Chondroitin/Dermatan Sulfate in Tumor and Brain Development

Cell behavior such as migration and proliferation, especially during cancer development, are balanced by the surrounding environment. Complex polysaccharides called glycosaminoglycans (GAGs) are part of this environment and they are known to modulate tumor development. One of these GAGs, dermatan/chondroitin sulfate (CS/DS), is attached to proteins either bound to the cell surface or secreted in t

Iterative receivers with channel estimation for MIMO and multi-user OFDM systems

The traffic in wireless networks has been showing an exponential growth over the last decade. In order to meet the demand, and support a continuation of this growth, the scarce radio resources need to be efficiently used. The use of multiple antenna (MIMO) systems and iterative (turbo) receivers has significantly improved the realizable system performance. Still, many challenges exist in the devel

On the validity of neurodevelopmental disorders

Abstract Introduction: Validity is important at different levels in psychiatry. Valid structured instruments are important aids in screening and diagnostics, in both research and clinical practice. An aim of the diagnostic procedure is to yield valid diagnoses. Ultimately, the validity of structured instruments (non-empirical) and clinical diagnoses depends on the validity of the diagnostic class

HOST EPIGENETIC REGULATOR BMI1 AND VIRAL FIBER PROTEIN FOR EQUILIBRIUM BETWEEN ADENOVIRUS AND HOST

Human adenoviruses (Ads) are broadly used in cancer gene therapy, vaccine development and gene delivery. The modified Ad5 or Ad2 viruses have been successfully used as oncolytic agents in pre-clinical studies. However they could not be translated into clinic utility due to a number of limitations including inefficient Ad spread among tumor cells. The cancer cell killing capacity of oncolytic Ad is

Measurement of trace components in aqueous solutions with near and mid infrared Fourier transform spectroscopy

This thesis treats various aspects of the measurement of trace components in aqueous solutions with Fourier transform infrared spectroscopy. This technique has several applications from such diverse fields as dairy industry and biomedical optics. The use of infrared spectroscopy for trace component quantification is made difficult by the large absorption of water which dominates the spectrum. The

Aspects on Cardiac Pumping

Cardiac pumping physiology is important for understanding the pathophysiology of patients with cardiac disease. MRI gives the opportunity to measure volumes and flow non-invasively with high accuracy and precision. This thesis examines some aspects on cardiac pumping physiology. Study I showed that the total heart volume in humans decreases during systole by ~8 % (range 5-11 %), and anatomically i

Effects of Sunlight on Organic Matter and Bacteria in Lakes

This thesis examines the role of sunlight, specifically ultraviolet-B radiation (280-320 nm), on dissolved organic matter (DOM) and bacteria in lakes. Field experiments in lakes with different humic contents and geographical locations have been performed. Photooxidation result in that part of DOM is oxidized to inorganic carbon (DIC), mainly CO2. The photooxidation rate can be of the same magnitu

Familjers och vårdpersonals erfareheter av barn och vuxna med autism. Families and staffs experiences of children and adults with autism.

The aim of this dissertation was to gain knowledge about the experiences of siblings and parents of children with autism and learning difficulties, about what brought about the decision to apply for a place in a group home for their child and what it meant for the parents that their child had moved. A further aim was to gain knowledge about what it is like to work in a group home for children with

Studies on cellular changes and amnesia in a rat model of electroconvulsive therapy

Electroconvulsive therapy (ECT) is a well-established treatment for severe depressive disorder, but its clinical use has been limited by concerns about side effects such as memory disturbances. Despite over 70 years in clinical use, the exact mechanisms of action behind the therapeutic or adverse effects are not fully understood. Enhanced brain plasticity, including neurogenesis, angiogenesis and

Chemical and Clinical Studies of Isocyanate Contact Allergy with focus on diphenylmethane diisocyanate

Isocyanates are highly reactive compounds used in the production of polyurethane. Exposure to isocyanates is mainly associated with respiratory disorders, but may also result in allergic contact dermatitis. Reports describing contact allergy to isocyanates are few in number and it has been considered a rare phenomenon. In the present study it is shown that the low frequency of reported cases could

Three-dimensional assessment of cardiac function; When right is wrong

Assessment of the right side of the heart is important in patients with heart disease; especially in patient with elevated pressure in the lung circulation. Decreased right ventricular function and elevated pressure in the right atrium are of poor prognostic value. Two-dimensional echocardiography (ultrasound of the heart) is the most commonly used method to assess the hearts function, but the rig

Regulation of normal and cancer cells as a base for cell cycle-targeted therapy

The majority of current treatments used for treatment of prostate cancer (PCa) and leukemia are often limited to a narrow subsets of treated patients. As such, there still remains a significant scope for gaining deeper understanding of molecular mechanisms underlying cancer metastasis for improvement of targeted treatment. Elevated expression of a cell cycle regulator cyclin A1 initiated leukemia

Articles on Potential Theory, Functional Analysis and Hankel Forms

Paper I: Perfekt, K.-M. and Putinar, M., Spectral bounds for the Neumann-Poincaré operator on planar domains with corners, to appear in J. Anal. Math., (2012). The boundary double layer potential, or the Neumann-Poincaré operator, is studied on the Sobolev space of order $1/2$ along the boundary, coinciding with the space of charges giving rise to double layer potentials with finite energy in the

Measurement of Tumor Extent and Effects of Breast Compression in Digital Mammography and Breast Tomosynthesis

Breast cancer is the most common form of cancer affecting women in the western countries. Today x-ray digital mammography (DM) of the breast is commonly used for early detection of breast cancer. However, the sensitivity of mammography is limited, mainly due to the fact that a 3D volume is projected down to a 2D image. This problem can be partially solved by a tomographic technique. Breast tomosyn

Laser-Driven Particle Acceleration - Improving Performance Through Smart Target Design

Laser-driven particle acceleration makes use of sub-picosecond, pulsed, high-power laser systems, capable of producing intensities ~10^{19} W/cm^2 at the laser focus to form plasmas, and use ultra-relativistic and nonlinear dynamics to produce quasistatic acceleration fields. This allows electrons to be accelerated to ~100 MeV over sub-centimetre distances, while protons may be accelerated to the

Psychiatric and metabolic disturbances in experimental models of Huntington’s disease

Non-motor symptoms and signs such as metabolic and psychiatric disturbances have been reported to occur early in Huntington’s disease (HD), a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. However, there is a lack of understanding of the underlying neurobiological mechanisms responsible for the early non-motor features. The hypothalamus has emerged as an