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Synthesis and Structural Characterization of Metal-Doped Titanate Nanotubes Using TEM, XRD and XAS

This work presents the synthesis and structural characterization of titanate nanoproducts, focusing on the effect induced by the presence of silver ion in different concentrations. The synthesis and chemical analysis using TEM, XRD and EDX were performed at the University of Szeged in Hungary. The XAS analysis was done at the MaxLab synchrotron facility in Lund University, Sweden. From the analysi

Analys av järnvägskapacitet

Analysis of rail capacity - Investigation of capacity limits Västkustbanan was first recognized by the Swedish Parliament over 50 years ago, when it was decided that the entire route would be equipped with phased out double-track extension. The main purpose was to cope with the future traffic development, along the railway corridor. Since the decision was made, the phased out double-track extensio

Utvärdering av Björkakorset i Sjöbo kommun, Skåne - En utvärdering av busshållplatser vid 2+1 vägar

Alternative 13-meter roads (2 +1 roads) has recently become a major part of the Swedish road network, in 2008 there were around 1280 km of 2 +1. Since these roads have major downsides for the vulnerable road users, it is important to review the design of the places where the vulnerable road users have to cross the road. The traffic is affecting both environment and humans at three levels, local, r

Överlåtelsebegränsningar - en jämförande studie

Principen om fri överlåtbarhet av aktier är central visavi idén om aktiebolaget som kapitalassociation och tjänar nyttiga syften. Dock finns goda skäl för undantag, varför överlåtelseförbehåll får nyttjas antingen i bolagsordning eller i aktieägaravtal. Rättsverkningarna skiljer sig väsentligt, men det finns för och nackdelar med en reglering vad gäller båda instituten. I svensk rätt accepteras

Biblioteksnedrustning i demokratin

Sedan 1990 och fram till 2009 har en tredjedel av Sveriges biblioteksfilialer lagts ned. Vårt arbete syftar till att studera orsakerna till varför den successiva nedläggningen av folk- och filialbibliotek sker, en frågeställning utan entydiga svar. I arbetet diskuteras olika tänkbara orsaksfaktorer, fokus ligger dock på en fallstudie av Växjö kommuns omstrukturering av sin biblioteksverksamhet. Vi

In Modernity’s Shadow: Sweden and Swedish Society in Swedish Language Instructional Material

This study discusses the image of Sweden and Swedish society in Swedish-language instructional material used in the Swedish-language course for immigrants (S.F.I.). As such, the main source material for this study has been different textbooks used as instructional material in the S.F.I. course from 1967-2005. Theoretically, this study takes its inspiration from the branch of discourse analysis kno

Image-Based Partial-Volume Correction in SPECT: Application to 177Lu radionuclide therapy

Introduction and aim: In SPECT imaging, the finite spatial resolution of the imaging system leads to a blurring of the reconstructed image. Consequently, counts originating from each point in the source distribution will be spread out over a volume in the reconstructed image, leading to spill-over of counts between different structures and distortion of the apparent activity concentration. This pr

Automatic segmentation of SPECT/CT-images using a deformable surface model based on Fourier descriptors with application in radionuclide therapy

Introduction: The purpose of this study was to develop a technique for automatic segmentation based on Fourier descriptors for separating smooth objects from the background in SPECT-images. The aim of the segmentation method was to be able to automatically outline kidneys in SPECT-images of patients undergoing radionuclide therapy with 177Lu-DOTATATE. The potential advantage of combining SPECT- an

Utilizing statistical process control analysis and EPID for routine QA of medical linear accelerators

Purpose: The main purposes of this study is to a) evaluate the suitability of a Varian aS1000 EPID as a safe quality assurance device for control of machine specific parameters, such as linac output, beam quality and beam symmetry, and b) to investigate the usefulness of the SPC concept for evaluation of the obtained data. Method and Materials: Measurements were performed using a Varian Clinac 23

An investigation of a potential multipurpose readout modality for two and three-dimensional dosimetry using optical computed tomography scanners

Radiochromic film, polymer gel and radiochromic plastic are three different kinds of dosimeters developed for radiation therapy. Even though all three types of dosimeters are suitable for optical scanning, the proposed readout method is different for each detector system. In this study, the scanning properties of three optical CT scanners were investigated to determine if they could be developed i

Improved analysis of MRI tractography data: Group comparisons of parameters along fibre tracks

Diffusion MRI is an imaging technique capable of inferring information about the tissue microstructure, based on magnetic resonance imaging (MRI). Diffusion MRI data can be analysed using tractography, a tool able to represent the structure of the white matter (WM) in the brain. Tractography is commonly used qualitatively, but in this report, an algorithm for quantitative tractography was develope

Diffusion Tensor Imaging in the Cervical Spinal Cord: Implementing methods for acquisition, processing and evaluation

Diffusion tensor magnetic resonance imaging (DT-MRI or DTI) is an imaging technique that is sensitive to the diffusion movement of water contained in tissue. It is used to quantify parameters such as the diffusivity and its directionality. Because diffusion is intimately connected to the tissue microarchitecture DTI is one of the few techniques that can quantify tissue microstructure non-invasivel

Effects of slabbing and slice thickness on image reading time and micro calcification detection in breast tomosynthesis

Breast tomosynthesis (BT) is a new X-ray modality that reconstructs the breast volume in many slices instead of, as in mammography, showing a single 2D projection of the breast. The slice thickness is typically 1 mm for clinically used BT-units. In screening the review of breast images with BT takes two to four times longer than the review of mammography images. In an effort to reduce the review t

Perfusion MRI: Non-Linear Stochastic Regularization for Deconvolution of Model-Free Arterial Spin Labelling Data

Introduction: Arterial spin labelling (ASL) is a non-invasive magnetic resonance imaging (MRI) technique for assessment of perfusion. ASL uses magnetically labelled blood water as a diffusible endogenous tracer to measure the perfusion of brain tissue, i.e. the cerebral blood flow (CBF). Traditionally, ASL samples images at a specific point in time allowing the CBF to be calculated using a model o

Informell rättsskipning som politisk metod

The thesis is an attempt to investigate the use of “informal justice as a political method” ( or “IRPM” in short) by the two Swedish right-wing organizations “info14/Fria Nationalister” and “Svenska motståndsrörelsen” using the organizations’ own web-published material for the period of 2000-2009, and to put the organizations’ use of “IRPM” into a Swedish empirical context. The thesis goes about

Interlocking directorates - En studie av fenomenets effekter i en kooperativ organisation

Syftet med vår uppsats är att studera förekomsten och effekterna av fenomenet interlocking directorates (överlappande styrelseuppdrag) i en styrelse inom en kooperativ organisation. Uppsatsens syfte är även att med hjälp av det empiriska underlaget förbättra och anpassa en teoretisk referensram till en kooperativ organisation. I metodkapitlet diskuteras varför vi har valt en abduktiv och kvalitati

The importance of sunk costs of exporting in risky situations

This paper investigates if the importance of sunk costs differs between markets with different exchange rate risk. First, it examines the importance of sunk costs on the export participation decision by estimating the effect the previous export status has on the current export decision. Second, it analyses the effects of product-market characteristics on the export participation decision. Third, i