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The biosynthesis of chlorophylls is an important process in nature. The green pigments play a fundamental role in absorbing and transferring solar energy to the photosynthetic apparatus. This thesis elucidates the role and function of the enzyme magnesium chelatase, which catalyses the insertion of magnesium (II) into protoporphyrin IX and is the first committed enzyme of the chlorophyll biosynthe
There are many examples of complex networks in science. It can be genetic regulation in living cells, computers on the Internet, or social and economic networks. In this context, Boolean networks provide simplistic models that are relatively easy to handle using computer simulations and mathematical methods. A good understanding of Boolean networks may form a foundation to investigations of more c
Epilepsy is a syndrome characterized by recurring attacks of sudden, excessive and synchronous discharge in populations of cerebral neurons. Kindling is an animal model for complex partial epilepsy, and is particularly useful for studies on the development of the abnormal excitability underlying the generation and spread of epileptic seizures. Here we have used the kindling model to investigate me
A comparison of essential oils from leaves of Eucalyptus camaldulensis Dehn. obtained by hydrodistillation (HD) and supercritical carbon dioxide (SC-CO2) extraction is presented. Selected major components of the oils showed a predominance of higher molecular weight components in the SC-CO2 extracts than in those obtained by HD. Physico chemical properties such as molecular weight, vapour pressure
The aim of the thesis is to contribute to knowledge of (1) psychosocial illness in the population, (2) the prevalence and nature of psychosocial illness encountered in primary health care, and (3) encountered among persons with long-term illness. The data collected include the results of a questionnaire given to a population-based sample of 13 000 persons (20-84 years), a questionnaire given to ge
The serotonergic vascular control was investigated by in vitro pharmacology in the human uterine and umbilical arteries. The localisation of immunoreactive (IR) neuropeptide Y (NPY) and the influence of NPY on the adrenergic vascular effects in the human uterine artery were also studied. NPY-IR nerve fibres were observed predominantly at the media-adventitial border of the uterine artery. About 50
This thesis concerns clean and adsorbate covered metal surfaces and surface alloys. These systems have been studied using theoretical and experimental methods. In the first part of the thesis, the different techniques that have been utilized in this work are presented, and the included publications are summarized. The second part of the thesis consists of seven original publications. In the first
The purpose of this dissertation is to explore the role of visibility in the production and contestation of belonging to political communities. On the basis of an empirical enquiry of Russian media during the 2010s, a theoretical conceptualization of the relation between visibility and belonging is suggested, starting in the idea that what becomes visible to publics and how, and what is rendered i
During moisture uptake in polymers, the diffusion of the water molecules is believed to occur via unoccupied voids. These voids are called free volume cavities and their sizes are continuously altered when the moisture content in the polymer is enhanced. Not only the free volume cavity sizes, but also other polymer properties such as the degree of crystallinity, are changed as a consequence of moi
Understanding of the growth of fatigue cracks is of utmost importance since such growth often has a profound influence on the life of components subjected to cyclic loading. Thus, reliable fatigue life models enable a more efficient use of materials and improve the performance and efficiency in many applications. This thesis deals with the growth of fatigue cracks subjected to high load amplitude
The xanthophyll cycle involves the light-dependent and reversible conversion of violaxanthin to zeaxanthin. The enzyme, violaxanthin de-epoxidase (VDE) catalyses the conversion of violaxanthin to zeaxanthin, via the intermediate antheraxanthin. VDE is a membrane-hosted enzyme during its activity. Low lumenal pH, violaxanthin, ascorbate and monogalactosyldiacylglycerol are required for activity. Th
It is important to replace fossil resources such as oil, coal and natural gas with renewable raw materials for the production of materials and fuels in order to reduce environmental impact. Furthermore, these raw materials should preferably be residues, e.g. agricultural or forest residues, in order not to compete with the production of human food and animal feed. High molecular weight arabinoxyla
This thesis is based upon four original papers in which human dendritic cells (DCs) and B cells have been analyzed in terms of how they influence the character of adaptive immune responses. DCs isolated from human tonsils were found to possess a capacity to directly regulate proliferation, isotype switching, and antibody production in B cells. DC-produced cytokines, including IL-13, were identifie
A network of perivascular nerve fibres was demonstrated in coronary arteries and veins from guinea-pig and man. Nerve fibres displaying immunoreactivity to neuropeptide Y (NPY) had a distribution pattern similar to those containing immunoreactivity to tyrosine hydroxylase. Immunoreactivity to substance P and calcitonin gene-related peptide (CGRP) occurred in the same varicose nerve fibres, which w
The aim of this dissertation is to address a paradox: government control and social freedom on China's Internet are growing simultaneously. The study, which is based on fieldwork conducted between 2002 and 2006, and 48 interviews, seeks answers to the following two questions: 1. How can Internet use contribute to an unlocking of the public sphere, making it more independent from party-state contro
In order to produce fuel ethanol from lignocellulose, it is necessary to hydrolyse the sugar-containing constituents hemicellulose and cellulose. During acid hydrolysis, a number of compounds are formed or liberated in addition to the fermentable monomeric sugars. Several of these compounds might act as inhibitors during the fermentation of the sugars to ethanol. Thus, in order to obtain high etha
The fundamental question in this work concerns the ideal relation between asceticism and society in a 5th c. writing (C.E.), the Philotheos Historia (PH), written in elaborate Greek by the learned bishop of Cyrrhus, Theodoret. This collection of saints’ stories tells about the lives of a number of ascetics who lived in the Eastern part of the Roman Empire, many of them close to Antioch. As these n
Plasticity induced damage evolution is considered using a thermodynamical approach. Different postulates on how to include the effects of damage in the constitutive equations have been studied. The results reveal that a mapping, similar to that of the stress, of both the kinematic and isotropic hardening variables is to be preferred. The undesired property that, irrespectively of the postulate emp
New measurements of the elements Ba, Fe, Ga, In and Ru are reported. The analysis of barium contains new wavelengths, improved energy level values and new values of the ionization limit in both Ba I and Ba II. Oscillator strengths and radiative lifetimes in Fe II, as a part of the FERRUM project, are reported. The gallium analysis includes new wavelengths, ab initio calculated oscillator st
Three main themes are outlined in this thesis: Polyelectrolytes/DNA : In a living cell, DNA molecules have a compact conformation in order to fit in, while in a test tube they will take on an expanded cylindrical shape, due to the negative phosphate groups along the DNA molecule. With the help of computer simulations it has been shown that like-charged monomers of a poly- electrolyte can attract
