Search results

Popular Abstract in Swedish Ett stort antal fåglar flyttar vår och höst mellan sina häckningsplatser hos oss i norr till “övervintringsområden”. Många flyttar över stora avstånd, till södra Europa eller till Afrika. Ofta är flyttfåglarnas mål väl definierat, det händer att en fågel häckar på exakt samma plats år efter år. Det finns observationer från t.ex. Afrika att fåglar kan vara lika trogna siBirds are generally capable of accurate orientation. In this thesis I present studies about the external cues and the ecological factors that influences bird orientation. A multitude of environmental cues are used to select and maintain a proper direction. These are visual cues, like the sun and the starry night sky, but other cues like the geomagnetic field, wind and odours also play important ro

Popular Abstract in Swedish Ytaktiva ämnen (tensider) har många olika användningsområden, bl.a. är de en viktig beståndsdel i tvättmedel, hygienprodukter och en del läkemedel och livsmedel. Tensider används av en mängd olika orsaker, t.ex. kan de stabilisera lösningar och lösa upp fett. Det speciella med dessa ytaktiva ämnen är att de består av en hydrofil del som gillar vatten och en hydrofob delThis thesis presents results of a series of experimental studies on the spreading dynamics of small drops of complex solutions on solid surfaces. The capillary flow dynamics of complex solutions have also been investigated. In the wetting experiments, water, alcohols, aqueous surfactant solutions and commercial ink-jet inks were used as test liquids, and a number of substrates, including silicate

The Swedish Knee Arthroplasty Register (SKAR) was initiated in 1975 to prospectively follow patients operated on with knee arthroplasty. With revisions utilized as the end-point in survival analyses, it is of importance that all revisions of included patients are reported. To validate if revision status was correctly recorded, a postal survey was made among all living patients, registered as opera

Heat transfer losses are one of the largest loss contributions in a modern internal combustion engine. The aim of this study is to evaluate the contribution of the piston bowl type and swirl ratio to heat losses and performance. A commercial CFD tool is used to carry out simulations of four different piston bowl geometries, at three engine loads with two different swirl ratios at each load point.

The excavations of one of the plots in the Black Earth at Birka revealed an unusually large number of objects associated with long-distance eastern contacts. Among the objects was a Volga Bulgarian pot and a hoard containing Volga Bulgarian imitations of dirhams. The surprisingly high proportion of Volga Bulgarian coins in the hoard indicates that the person(s) who lived on the plot in the mid ten

The generalized Pareto distribution (GPD) is a two-parameter family of distributions which can be used to model exceedances over a threshold. We compare the empirical coverage of some standard bootstrap and likelihood-based confidence intervals for the parameters and upper p-quantiles of the GPD. Simulation results indicate that none of the bootstrap methods give satisfactory intervals for small s

This chapter is intended as a background on natural photosynthesis for those interested in artificial photosynthesis. It describes how light is used for creating positive and negative charges, and how these charges are transferred through the molecular assemblies in the membranes. Next, the chapter also describes how the charge transport leads to creation of a pH difference across the photosynthet

Bone and soft tissue tumors (BSTT) belong to a diverse group of solid tumors of mesenchymal origin, with a large number of histological types affecting individuals of all ages. The general aim of the present thesis (Articles I-V) was to investigate in detail the genetic aberrations in selected subtypes of benign and malignant BSTT. Aberrations identified by chromosome banding analysis were studied

The sensitivity of biosensors can be increased substantially by incorporation in a substrate recycling scheme. Based on the amplification of NAD+/NADH by the recycling reaction catalyzed by glycerol dehydrogenase (GDH) and diaphorase, NAD+/NADH can be determined amperometrically with around 1000 times higher sensitivity than for the substrate sensing mode. The sensitivity of enzyme electrodes were

The general aim of this thesis was to study how memorial places and objects serve as links and meeting points between the bereaved and their conceptions and memories of the departed. This has been examined in several different ways, from various viewpoints, and placed in different contexts and periods in time. The general result is that there are several and complementary ways through which materi

riskhantering, krishantering och lärande, tekniska infrasystems sårbarhet, risk- och sårbarhetsanalys, krishanteringssystem