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Popular Abstract in Swedish Fysiologiska och biokemiska processer i den levande kroppen kan studeras mha spårämnestekniken positronemissions tomografi (PET). Den bildgivande tekniken PET kräver radionuklider som sönderfaller genom att sända ut en positron. Positronen är antimateria till elektronen. När positronen har en mycket låg rörelseenergi och träffar på en elektron, ombildas deras vilomassorPositron emission tomography (PET) is a tracer technique used for quantitative in vivo studies of physiological and biochemical processes. Because of the use of positron-emitting radionuclides such as 11-C, 13-N, 15-O and 18-F, which are isotopes of the biologically ubiquitous elements, it is possible to label radiopharmaceuticals which trace biochemical processes precisely. In order to be able to

Growth conditions on acid soils may be hampered by low nutrient availability and phytotoxic Al (aluminium) concentrations. In this thesis I present my studies on adaptation mechanisms of wild plants to acid soils in the close root environment, the rhizosphere. The studies showed that plants have developed several mechanisms that may work simultaneously to face the complex soil chemistry. A first g

There is increased evidence to support the hypothesis that humanity actively, albeit inadvertently, contributes to global environmental change on a scale and with an intensity unprecedented in human history. Climate change, and to some extent stratospheric ozone depletion, present the international structures and systems for naturalresources management research and politics with fundamentally new

This thesis is a summary of five papers concerning endocyclic cleavage of glycosides and related acetals. Simple lactol ethers undergo endocyclic cleavage to give acyclic chain extended products on treatment with organoaluminium and organotitanium reagents. The first examples where organotitanium reagents induced alkylative endocyclic cleavage of carbohydrates is presented. The best conditions for

Popular Abstract in Swedish Att mäta det icke observerbara: Vilka chefer väljs till toppositioner? Rekrytering och urval av chefer präglas till stor del av informationsosäkerhet. Det är svårt att utvärdera chefers prestationer, då deras ansvarsområde består av så många aspekter, då de behöver stor frihet i sitt arbete och därför inte kan kontrolleras alltför mycket och då deras arbete påverkas avRecruitment and selection of managers is to a large degree characterized by information uncertainty. Managers’ performance is difficult to evaluate, as their responsibility consists of so many different aspects, as they may not always be observed due to need for freedom of action and as their work is affected by factors in their environment, which are outside of their control. Also, selection deci

Transnational stardom, in the sense that particular star actors constitute a genuine draw for audiences in other European countries than that of the film’s origin, appears an increasingly rare thing within the continent’s cinema. In short, a transnational star system is wanting. Had it existed, more attractive films would most undoubtedly be a reality. Furthermore, with such a system in place film

Popular Abstract in Swedish Graden av genetisk variation inom och mellan olika populationer bestäms av balansen mellan tre faktorer: naturligt urval, slumpmässig genetisk drift och genflöde. Genom studier av genetisk variation är det möjligt att dra slutsatser om t ex selektionstryck på olika alleler (genvarianter), arters spridningsvägar till nya platser, tid sedan etablering och graden av släktsIn this thesis I present studies concerning genomic diversity and genetic heterogeneity as well as the evolution and maintenance of genetic variation at a specific immune defence gene in Atlantic salmon (Salmo salar, L.). I here present data on nucleotide diversity showing that human activities as well as different post-glacial colonisation events have had considerable effects on the genomic diver

Evolutionary change results from selection acting on genetic variation. For migration to be successful, many different aspects of an animal's physiology and behaviour need to function in a co-coordinated way. Changes in one migratory trait are therefore likely to be accompanied by changes in other migratory and life-history traits. At present, we have some knowledge of the pressures that operate a

BACKGROUND: Use of a catheter-free, radio telemetric, oesophageal pH-monitoring system in paediatric clinical practice allows patients to follow a more normal physiological pattern of activities and causes less discomfort. At our institution, placement of the capsule is done under general anaesthesia, which restricts the child's activity during the first day. The aim of this study was to determine

Aims/hypothesis Among diabetic patients, glucose homeostasis may be affected by abnormal gastrointestinal motility and autonomic neuropathy. This study analysed whether oesophageal dysmotility, delayed gastric emptying or autonomic neuropathy affect glucose homeostasis. Materials and methods Oesophageal manometry and gastric emptying scintigraphy were performed in 20 diabetic patients. Heart-rate

Background: In several studies, patients with alcohol dependence treated with the opioid antagonist naltrexone have shown fewer relapses to heavy drinking than those receiving placebo. An interaction between the naltrexone effect and the type of psychological therapy has been observed. Methods: A 6-month, double-blind, placebo-controlled, parallel-group study was performed at 10 different investi

Objectives: A potential role in cancer biology is suggested for YKL-40 (CHI3L1, HC gp-39). The purpose of this study was to evaluate the clinical value of serum YKL-40 (sYKL-40) in multiple myeloma (MM) and to examine YKL-40 expression in malignant plasma cells (MM PCs). Methods: sYKL-40 was measured by enzyme-linked immunosorbent assay (ELISA) in 82 patients with newly diagnosed MM. YKL-40 expres

Popular Abstract in Swedish I plan to add a summary in Swedish at the WWW-page www.biokem.lu.se/education/theses/johannordthesis.htmRecombinant dUTPase from the bacterium Escherichia coli, the retrovirus equine infectious anemia virus (EIAV) and Homo sapiens have been made available for physico-chemical characterisation. The protocols developed have also proven to be suitable for production of enzymes modified by isotope labelling or other methods. The improved accessibility of enzyme material has enabled the subsequent invest

Recent advances in laser technology, with the development of extremely short-pulse, high-intensity lasers, have opened doors to new areas in atomic physics. By focusing light from an intense, short-pulse laser into a gas jet, the emission of high-order harmonics of the laser frequency has been studied. The aim of this work has been two-fold: to better understand the underlying physics of the harmo

Popular Abstract in Swedish Hjärt-kärlsjukdomar är en ledande orsak av sjuklighet och dödlighet. Med hjälp av dagens moderna ultraljudsteknik är det möjligt att påvisa även begynnande, mycket diskreta kärlförändringar. En tidig upptäckt av dessa kan bli av betydelse för individens framtida hälsa. I ett antal studier har vi med hjälp av ultraljud undersökt kärlens styvhet och förmåga att vidgas (enCardiovascular disease (CVD) is one of the leading causes of mortality and morbidity. Early recognition of vascular changes, both structural and functional, may help to identify individuals at risk for CVD. Using modern ultrasound techniques – the echo-tracking technique for assessment of stiffness in large arteries and flow-mediated dilatation of the brachial artery as an indicator of endothelial

The success of the IEEE 802.11 standard has prompted research into efficiency of the different medium access methods and their support for different traffic types. A modified version of the point coordination function (PCF) called modified PCF has been introduced as a way to improve the efficiency over the standard method. It has been shown through a simulation study and a mathematical analysis th

Popular Abstract in Swedish Kunskapsarbete framställs ofta som något som präglas av dolskhet eller oklarhet: produkten som säljs är oklar, resultatet är oklart och även själva arbetsprocesserna framställs ofta som oklara. Detta påverkar i sin tur den styrning som man kan förvänta sig i kunskapsintensiv verksamhet: en styrning som ofta handlar om personalen mer än om arbetet. I denna studie problemKnowledge work is often portrayed as hidden or ambiguous: an ambiguous product is sold, ambiguous results are delivered, and work processes are ambiguous. This in turn affects the type of management expected in knowledge-intensive organisations, where emphasis is on managing people rather than work. In this study, the organisation of knowledge work is discussed and problematized through analysis o

Popular Abstract in Swedish Den här avhandlingen studerar olika statistiska metoder för att utvinna information som ligger dold i en serie av tal eller andra symboler, exempelvis bokstäver. En sådan serie kan innehålla slumpmässighet eller ha vissa mätbara statistiska egenskaper, men har även ett inneboende mönster, vilket vi är intresserade av. Vi kallar vanligtvis sådana serier för signaler, ochThis thesis examines sparse statistical modeling on a range of applications in audio modeling, audio localizations, DNA sequencing, and spectroscopy. In the examined cases, the resulting estimation problems are computationally cumbersome, both as one often suffers from a lack of model order knowledge for this form of problems, but also due to the high dimensionality of the parameter spaces, which

Jobs and economic growth are created where businesses are located and investments made. A number of factors affect where firms choose to locate and where and how much that is invested. Many of these factors are hard to influence in the short run while others are governed by politicians and can be designed in order to stimulate desirable business and investment behaviour. One such factor is taxatio

Objective To assess intraobserver and interobserver variability in ovarian volume and gray-scale and color flow index measurements using transvaginal, three-dimensional, power Doppler ultrasonography. Methods Eleven women (22 ovaries) were examined on day 8 of controlled ovarian hyperstimulation therapy, which was part of their in vitro fertilization treatment protocol. The patients were examined