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In this thesis, I have investigated factors (cues, benefits, and costs) affecting the evolution of an inducible morphological defence in crucian carp (Carassius carassius). Inducible defences are favoured over permanent defences when prey have reliable cues to detect predators, when defences are effective but costly, and when predation pressure is variable and unpredictable, but sometimes s

Pancreatic cancer includes multiple histologic subtypes that show large differences in their clinical and biological characteristics. Despite this diversity, more than 85% of the neoplasms in the organ are malignant ductal adenocarcinomas, which are the focus of the present thesis. At the genetic level this tumor type is characterized by highly rearranged karyotypes, resulting in a large number of

The word sustainability is more and more frequently used within the field of chemistry and in many other fields. Green or sustainable chemistry was introduced during the 90 ́s as a field of chemistry where the environmental and health impacts of processes and products are evaluated and improved. Within analytical chemistry the awareness of sustainability has also increased, which has resulted in o

This thesis explores models and algorithms in geostatistics and gene mapping. The first part deals with the use of computationally effective lattice models for inference of data with a continuous spatial index. The fundamental idea is to approximate a Gaussian field with a Gaussian Markov random field (GMRF) on a lattice, and then to conduct a bilinear interpolation of this at non-lattice location

The extracellular matrix plays an integral role in tissue remodeling and development and it defines the different mechanical properties of a variety of connective tissues. Its complexity in composition and the details in organization has only been partly elucidated. This thesis focuses on collagen VI and the mutual interactions of a number of matrix proteins that lie within close proximity. Collag

The air traffic control industry in Europe is under mounting pressure due to increasing air traffic and inefficient routines caused by a fragmented air space. In order to handle the demands the European Commission has launched a program entitled the Single European Sky initiative which seeks to promote a more efficient way of handling the air traffic over Europe. A reorganization of air traffic ma

Congestive heart failure is accompanied with increased circulatory levels of several vasoregulatory neurotransmitters and hormones which affect the outcome of this disease. In this thesis the blood levels of several vasoactive peptides in humans with congestive heart failure and their effects on the vasculature by the use of an animal model of heart failure were studied. Patients with congestive

Cholecystokinin (CCK) is known to exert secretory and trophic effects on the pancreas. Its release from the intestinal mucosa is regulated by pancresic proteases in the small intestine. However, knowledge about the type of responding exocrine cells and the time course of events during stimulation with CCK is lacking. Further, the role of CCK in the regulation of growth in other digestive organs is

In the work presented, nuclear magnetic resonance (NMR) relaxation is used to study wide range of systems. The thesis concerns solvent interactions studied with relaxation techniques that involve measurements at many fields, which allows the separation of individual relaxation mechanisms. The approach also makes it possible to characterize the involved dynamic properties in much greater detail. T

Dolerite dykes are formed when iron- and magnesium-rich (mafic) mantle-derived magmas ascend through the lithosphere (upper part of the mantle) and crystallize as ‘hydro-fractures’ within the crust. Dykes may exist in great numbers to form dyke swarms (linear or radiating), which can be linked to time periods of continental break-up, or attempted break-up events, associated with voluminous volcani

It is of vital importance to understand the systems for iron metabolism and this thesis contributes to this by providing insights into the structure and function of the acquisition and homeostasis of iron. The two proteins that have been primarily investigated are a ferric reductase from Arabidopsis thaliana called FRO2 and a mitochondrial iron chaperone from Saccharomyces cerevisiae called fratax

This thesis deals with cardiovascular and respiratory effects of apneas in humans. During apnea (breath-holding), a number of interacting cardiovascular reflexes are initiated, and together these reflexes are called the “diving response”. The main cardiovascular characteristics of the human diving response are reduced heart rate, decreased cardiac output, peripheral vasoconstriction, and increased

Prosthetic loosening, bone graft resorption and osteonecrosis are examples of problems in orthopedic surgery caused by or augmented by bone resorption. Bone resorption is caused by osteoclasts. Osteoclasts can be inactivated with biphosphonates, a drug in clinical use against osteoporosis and osteolytic tumors. The bone resorption-reducing ability of bisphosphonates was analyzed in rat models. An

The partitioning behaviour of different types of molecules in thermoseparating two-phase systems has been studied. A thermoseparating two phase system was formed by heating a water solution, which contained a thermoseparating polymer, above the cloud point temperature. The thermoseparating polymers studied were: random copolymers of ethylene oxide and propylene oxide (EOPO-polymers), and ethyl(hyd

During the course of evolution animal complexity and diversity is generated. The last couple of years it has become increasingly clear that morphologically diverse animals share a great deal of their genomic contents, and it must be the expression of regulatory genes in new setting, rather than the generation of new genes, that are fundamental for the generation of diversity. Basal phyla hold a ke

The serine proteases cathepsin G, leukocyte elastase, proteinase 3, and the inactive protease homologue azurocidin, stored in the azurophil granules of neutrophils, belong to a hematopoietic serine protease superfamily with members in mature effector cells of bone marrow origin. Promonocytic U-937 cells were used for studying the biosynthesis of cathepsin G and leukocyte elastase by biosynthetic r