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Magnesium chelatase and ferrochelatase are two very important enzymes, which are involved in chlorophyll and heme biosynthesis, respectively. They both use protoporphyrin IX as substrate but magnesium chelatase inserts a magnesium ion whereas ferrochelatase inserts a ferrous ion. These two enzymes have been studied in this thesis. Even though they both insert a metal ion into protoporphyrin IX the

This thesis is about high energy heavy ion physics. Two major experiments, the WA98 at CERN and the PHENIX at Brookhaven National Laboratory, are described. Results from data analysis from both experiments are presented. The WA98 chapter presents particle identification methods and phi-meson measurements. A procedure for calculating efficiency maps for tracking chambers is discussed. The PHENIX ch

Traveller information designed to fulfil needs and expectations of individual travellers is a key factor in improving access for older people and people with disabilities to public transport. The overall aim of this thesis is to contribute to the knowledge of user and provider perspectives on the provision of traveller information for older people and people with disabilities in public transport w

Stroke is an acute neurological condition and the leading cause of disability in adult humans. Treatments for efficient recovery are not available. The most common form of stroke results from the occlusion of the middle cerebral artery, which causes loss of brain parenchyma and many types of neurons as well as astrocytes and oligodendrocytes. Neural stem cells (NSCs) could potentially be used to d

B-cells are an essential part of our adaptive immune system. A network of transcription factors together with external signals facilitate the gradual developmental progression from progenitor cells towards the B-cell fate. Several key factors participating in this network have been identified. Among these are the transcription factors E2A, HEB, EBF1 and FOXO1 as well as the IL7 signaling cascade.

In this thesis, an inverse source reconstruction method with great potential in radome diagnostics is presented. A radome is a cover that encloses an antenna in order to protect it from environmental influences. Radome diagnostics are acquired in the design process, the delivery control, and in performance verification of repaired and newly developed radomes. A measured near or far field may indic

In human cells there are usually two copies of each chromosome, but in cancer cells abnormalities could exist. The differences consist of segments of chromosomes with an altered number of copies. There can be deletions as well as amplifications and the lengths of the segments can also vary. Localising the deviant regions is of great importance for increasing the knowledge of the disease. In this t

Parkinsons disease (PD) is a neurodegenerative disorder where dopaminergic neurons of the substantia nigra (SNc) in the mesencephalon are progressively eliminated. The ensuing loss of dopaminergic innervation of the basal ganglia manifests itself as severe motor deficits in PD patients. Clinical trials have shown that cell replacement therapy, where dopaminergic neuroblasts derived from fetal vent

It has been shown that the present interglacial has been climatically dynamic with both rapid and severe climatic fluctuations. The spatial and temporal differences of these changes are however not fully resolved. The aim of this thesis is to present a detail high resolution record of past climate changes from the central South Atlantic. Peat and lacustrine sediment sequences were retrieved from

Urban areas are geographically dispersed. There are built-in distances between housing, jobs and services. These distances call for mobility and fast means of conveyance. Society is dominated by and dependent on motoring. Cars have a negative impact on the environment and prognoses indicate an increase in the amount of travelling. The aim of this dissertation is to explain why travel behaviour wit

Osteoarthritis (OA) is the most common joint disorder worldwide, causing joint pain and stiffness. The current gold standard for diagnosing knee OA is radiography. However, the disease has often progressed well beyond the point of no return once radiographic cartilage changes become visible. Identifying changes in cartilage at an early stage of OA would allow curative or prophylactic treatment to

Both presence and extent of myocardial infarction are important prognostic factors for mortality and quality of life in patients with ischemic heart disease. Thus, it is of great clinical importance to be able to diagnose and characterize myocardial infarction. One way to diagnose myocardial infarction is by using the 12-lead electrocardiogram(ECG). For estimation of infarct size and location from

This thesis consists of six articles on three different subjects in the area of complex analysis, operator theory and harmonic analysis. Part I - "The Shift Operator on Spaces of Vector-valued Analytic Functions" consists of three closely connected articles that investigate certain operators in the Cowen-Douglas class with spectrum D - the unit disc, or equivalently, the shift operator M_z

As Sustainable development, a widely used but poorly understood term, challenges traditional scientific values such as prediction and control, scientists have tried to manipulate the concept to promote their own particular agendas. Thus, it has suffered from misrepresentation which has prevented the concept from being fully implemented at a practical level. It is asserted that traditional fragmen

Infectious diseases constitute a major global health problem. The presenting clinical picture results from a mixture of direct toxic actions by the microbiological agent and of the immune response mounted by the host. There is often a rapid onset, which may constitute a diagnostic and therapeutic challenge, whereas in other cases an extensive investigation over a long time period can fail to ident

Arctic ecosystems represent an important component in the global terrestrial exchange of greenhouse gases and energy with the atmosphere. In the changing climate, which is most pronounced in the Arctic, the possible scenarios of greenhouse gas exchange response should be seriously considered in predictive climate modelling efforts. As a prerequisite for this, detailed studies of key processes affe

The theory of stochastic time-frequency analysis of non-stationary random processes has mostly been developed for processes in continuous time. In practice however, random processes are observed, processed, and interpreted at a finite set of time points. For processes in continuous time, the ambiguity domain has interesting properties which makes it particularly useful. One such property is that t