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During the last decade it has been shown that nitric oxide (NO) and carbon monoxide (CO) are produced in our own body, and that they constitute a novel class of messenger molecules. In 1992 a constitutive NO-producing NO-synthase (cNOS) was found in the islets of Langerhans, and in 1997 we could show for the first time that the islets also contained a CO-producing constitutive heme oxygenase (HO-2

Exposure to isocyanates may induce disorders in the airways of workers. Therefore, application, development and validation of methods for exposure assessment is of great importance. In the present study, we have determined the personal air and biomarker levels of isocyanates for a group of occupationally exposed workers (n=170) in different types of industrial processes. Also, the biomarker levels

The technology of cDNA microarrays has given us the possibility to monitor the state of cells by measuring the activity of thousands of genes simultaneously. This high-throughput techniqe has in cancer research allowed exploratory studies of molecular mechanisms behind for example metastasis and response to therapy. This increased knowledge can hopefully result in new therapies and improved progno

The available bandwidth in wireless communication systems, such as the 802.11 family, is very limited. Together with the ever increasing data traffic, this causes problems. New possibilities are, however, available thanks to wide license-free bandwidth allocated at higher frequencies. Increased available bandwidth enables higher data rates in future radio systems that will be capable of Giga-bit/s

This thesis concerns a numerical investigation on heat transfer in internal combustion engines, with the aim of increasing engine efficiency. The efficiency gains are to be extracted from reduced heat transfer losses, by increasing the knowledge on how the heat transfer process is affected by various hardware and operational parameters in the engine. The engines concerned are both conventional die

The interaction between an intense laser pulse and a gas medium leads to the emission of coherent bursts of light in the extreme ultraviolet range. This process, known as high-order harmonic generation, has today, almost three decades after its discovery, developed into a reliable source of extremely short (on the order of 100 as) pulses of electromagnetic radiation, with a wide range of applicati

Airborne particles are everywhere around us, and have always been. Particles generated by human activities has increased drastically since industrialization, and several epidemiological studies have shown that inhaled particles can cause adverse health effects. The concern about health effects have during the last decade shifted towards fine and ultrafine particles, not least due to the emerging f

This thesis includes two different parts: One focusing on how to induce human embryonic stem cells (hESCs) to differentiate into insulin producing cells by following the normal pancreatic development pathway. These cells have then the potential to be an unlimited source for diabetes regenerative medicine. The second part of the thesis deals with how embryonic stem cells rid themselves of damaged p

Mature blood cells are crucial for life, but they have a short lifetime and thus have to be replaced. These mature blood cells are produced by lineage restricted progenitors, which themselves are generated by rare multipotent hematopoietic stem cells (HSCs) in a highly dynamic process called hematopoiesis. In addition to the ability of HSCs to generate all blood cell lineages, they possess the uni

A highly dealuminated form of zeolite FAU, ultra-stable zeolite Y (USY), was used as an adsorbent matrix in the purification of proteins. Undesired proteins were removed from a crude preparation by adsorption on USY, increasing the purity of an unadsorbed protein (horse radish peroxidase), or the protein of interest was adsorbed on the zeolite and subsequently eluted through changes in the solutio

The aim of this thesis was to investigate and describe different aspects of variation in the Dactylorhiza maculata complex and to relate the variation patterns to underlying biological processes such as Quaternary migration history, hybridization and polyploid evolution. The variation patterns were analysed at various geographic levels using molecular markers (plastid DNA and ITS of nrDNA), cytolo

Proton nuclear magnetic resonance (NMR) was used to study the self-diffusion of water in porous systems that respond to a change in water content in order to elucidate the porous structure and the properties of the confined water. In the carbohydrate systems cellulose fibers and starch granules, water is free to move throughout the porous objects, albeit with a rate reduced from the value of the

Specific language impairment (SLI) is commonly described as a condition where a child with otherwise normal development and hearing does not acquire language as expected. Children with SLI often have a family history of language disorders. The aetiology is poorly understood. In the first two studies, event-related brain potentials(ERPs)evoked in response to tone- and to speech stimuli were record

Evaluation of long-term side effects of treatment is important due to the growing number of childhood cancer survivors. How kidney function is affected over time needs to be clarified. In the first article, we investigated 247 healthy infants and children and established upper reference limits for several proteins in urine, to be used as markers for glomerular and tubular proteinuria in children w

It is attractive to integrate a large deformable mirror for adaptive optics into an astronomical telescope rather than using relay optics within an auxiliary instrument. However, the resulting large deformable mirror can be expensive, particularly for extremely large telescopes. We have pursued a low-cost approach using force actuators connected to the back of the deformable mirror through suction

The overall aim of this thesis was to increase our knowledge of the relationship between structure and function of human skeletal muscle, and about factors affecting strength. The ankle dorsiflexor muscles (DF) were chosen as a representative model of human skeletal muscle, and because these muscles have important roles in gait and maintenance of balance. Specific aims in this thesis were: i) to d

Transplantation is the only cure for end-stage organ failure. With the transplantation follows the need for continuous treatment with immunosuppressive agents for as long as the graft functions, which entails major side effects. Less toxic treatments are therefore in great demand. Preferably, the treatment should also be limited in time. The ultimate solution would be induction of tolerance to t

HAMLET (human alpha-lactalbumin made lethal to tumour cells), a protein-lipid complex originally isolated from human milk, induces programmed cell death selectively in tumour cells. It consists of partially unfolded alpha-lactalbumin in complex with oleic acid. It was previously not known if the unfolding of alpha-lactalbumin alone accounts for the activity of HAMLET or if the lipid adds biologica

The inhibitory neuromuscular control of the human and cat lower oesophagus was investigated by morphological, functional, and biochemical methods. A supply of nerve fibres and myenteric cell bodies, containing nitric oxide synthase (NOS), haem oxygenase (HO)-2, vasoactive intestinal peptide (VIP), and pituitary adenylate cyclase activating peptide (PACAP) was observed. The highest density of nerve

Proteolytic enzymes are enzymes that hydrolyze peptide bonds in peptides and proteins. This ability to carry out protein degradation is essential for many cellular and extracellular processes that occur in all living organisms. Cysteine peptidases constitute a class of proteolytic enzymes. Among these, papain-like (C1) peptidases are the mostly studied ones. Inhibitors regulate proteolytic activit