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Pollen Competition as a Target for Sexual Selection in Plants

According to the theory of sexual selection, traits can evolve because they confer a mating advantage in competition with members from the same sex. In animals, sexual selection is considered as an important evolutionary force. In this thesis I have investigated the potential for sexual selection in plants. I have concentrated on the phase of reproduction that occurs after pollinators have deposit

Electron Transport in Semiconductor Nanowires

In this thesis, semiconductor nanowires are studied from the point of view of growth and electrical properties. The growth of nanowires is done by chemical beam epitaxy (CBE), an ultra-high vacuum technique allowing a precise control of precursor deposition and low growth rates. In conventional epitaxy, growth is usually two or three- dimensional, depending on growth conditions and material combin

Trait anxiety as a determinant of psychological test results

This thesis deals with the problem of interpreting test scores. The intention has been to explore and elucidate the effects of trait anxiety on test scores that have been obtained in applied research settings. Paper I showed that different relationships between personality traits and cognitive functioning emerged in a group of men with solvent induced chronic toxic encephalopathy (TE; N=57) compa

Elastic Properties of Nanowires - an Atomistic Evaluation

Nanowires constitute one of the fundamental building blocks in assembled nanodevices. Due to the high surface to volume ratio, the fraction of surface atoms is not negligible for nanosized elements. Because of the reduced coordination of surface atoms, the physical properties deviate from those of the bulk, which influences the overall physical properties of nanostructures. Consequently, this prov

Magnetotransport Studies of Mn Ion-Implanted Nanowires

This thesis focuses on the magnetotransport properties of highly Mn-doped crystalline GaAs nanowires. The GaAs nanowires were first grown by metal-organic vapor phase epitaxy from gold seed particles, and subsequently implanted with Mn ions under varying conditions, e.g., ion fluence and acceleration voltage. The implantation process was carefully analyzed and optimized within the research project

From Time-Averaged to Time-Resolved Crystallography: Studies on Superoxide Dismutase and Myoglobin

We have studied protein motions with nanosecond time-resolved crystallography. The release of carbon monoxide from its complex with myoglobin (MbCO) was triggered by nanosecond laser pulses. X-ray data were collected with time delays ranging from 4 ns to 1.9 ms using the Laue method, at the European Synchrotron Radiation Facility in Grenoble. For the first time point, X-ray pulses of 150 ps durati

Development of low affinity techniques for applications in clinical chemistry

An increase in the plasma level of creatine kinase MB (CKMB) has long been used to indicate acute myocardial infarction (AMI). For optimal treatment an early diagnosis is important. An increase in the ratio between the two isoforms of CKMB is seen much earlier than an increase in the total level of CKMB. One possible method for separating these isoforms could be weak affinity chromatography (WAC).

Irradiation of members of the general public from radioactive caesium following the Chernobyl reactor accident. Field studies in a highly contaminated area in the Bryansk region, Russia.

From 1990 to 1998, estimations of the effective dose from external as well as internal irradiation from 137Cs and 134Cs were carried out for inhabitants in rural villages in the Bryansk region, Russia, highly contaminated due to the Chernobyl accident in 1986. The villages were situated about 180 km from the Chernobyl power plant and the deposition of 137Cs was in the range 0.9-2.7 MBq m-2. Yearly

Plant Calreticulins - isoforms, localization and function

Calreticulin (CRT) is an endoplasmic reticulum (ER)-located protein involved in quality control of newly synthesized proteins as well as in calcium homeostasis of the cell. Most of what is known about CRT arises from studies of mammalian systems. However, using a Arabidopsis thaliana CRT gene expressed in mouse fibroblasts deficient of endogenous CRT, the wild type phenotype could be rescued with

Effects of Probiotics and Plant Components on Murine Experimental Colitis and Acute Liver Failure

Acute liver failure is accompanied by a high rate of bacterial septic complications. High portal level of lipopolysaccharide (LPS) can lead to a pronounced secretion by Kupffer cells of pro-inflammatory mediators which have been shown to be early and important mediators of liver injury. Pathogenesis of inflammatory bowel disease (IBD) is complex; involving environmental, genetic, microbial, and im

Nuclear magnetic resonance and microcirculation: The influence of pulsatile brain-tissue motion on measurements of intravoxel incoherent motion and assessment of haemodynamics using exo- and endogenous tracers

In this project, the potential of magnetic resonance (MR) imaging and spectroscopy in studies of microcirculation and haemodynamics was evaluated. The spatial and temporal characteristics of human pulsatile brain-tissue movements in healthy individuals, relevant for the understanding of the cerebrospinal-fluid (CSF) circulation and the pathogenesis of hydrocephalus, were thoroughly investigated. A

Late-life depression from a primary care perspective

Studies have found that depressive states in old age that do not fulfil the criteria for major depression are clinically important depressive states. These depressive states are common in primary care patients. Therefore, studies of late-life depression from a primary care perspective are needed. A depressive rating scale, Hopkins Symptom Checklist-25 (HSCL-25), was used in a community survey in 1

A Study on Trypanosomal Polyamine Biosynthetic Enzymes

The polyamines, putrescine, spermidine, and spermine, are essential for all forms of life. The polyamine biosynthetic pathway has been shown to be a potential target for drugs against various trypanosomal parasitic diseases. The two main enzymes in the biosynthesis of polyamines are ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC). ODC catalyzes the first step of pol

99mTc-DMSA renal scintigraphy in the diagnosis and follow-up of acute pyelonephritis in children.

The aim of the present thesis was to define and evaluate a strategy for identification of children who are at risk of developing progressive renal lesions after acute pyelonephritis. Tc-DMSA renal scintigraphy is widely accepted as the most sensitive method for detecting parenchymal lesions and diagnosing acute pyelonephritis. Qualitative and quantitative evaluation standards were elaborated to i

Platelet-dependent pulmonary recruitment of neutrophils in abdominal sepsis

Sepsis and subsequent multiple organ failure remain the major cause of mortality in intensive care units. Leukocyte-mediated tissue damage is a key feature in septic lung injury. Accumulating data suggest that platelets play a role in inflammation and tissue injury. However, the role of platelets in sepsis-induced leukocyte recruitment and lung edema formation in abdominal sepsis is not demonstrat

Manganese cycling in the Baltic Sea over the last ~8000 years: the influence of redox conditions on mineral formation and burial

The Baltic Sea is one of the largest brackish water bodies in the world and is suffering extensive environmental issues caused by eutrophication and warming climate. A halocline in the water column divides more saline bottom water fed by inflows through the narrow connection with the North Sea from the surface waters and inhibiting exchange of oxygen between the two water masses. With the nutrient

Microcultures in the meso level of higher education organisations – the Commons, the Club, the Market and the Square

Higher education (HE) is and has been a growing concern for various stakeholders for a considerable time. Sometimes contradictory attempts to reform HE have increased the pressure on academic teachers and contributed to an experience of demand overload. This research conceptualises HE organisations so that dynamics related to change and stability become understandable. A socio-cultural perspective

Fat bloom on chocolate confectionery systems - From core to surface

Abstract Fat bloom on chocolate is a major problem for the confectionery industry since the unappetising appearance and negative sensory effects lead to rejection by customers. The presence of fat bloom on chocolate confectionery systems is usually connected to migration of liquid fat due to the difference in composition between filling triacylglycerols (TAGs) and cocoa butter TAGs. The filling T