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Monte Carlo Simulation of Transmission Studies using a Planar Sources with a Parallel Collimator and a Line Source with a Fan-Beam Collimators

A knowledge of the distribution of the attenuation coefficient is generally required for a successful correction of attenuation in nonhomogeneous regions. This can be accomplished by performing transmission measurement with either parallel or fan-bean collimation. The Monte Carlo method makes it possible to fully evaluate the results of such a correction. This study shows results from such simulat

Genome characteristics of primary carcinomas, local recurrences, carcinomatoses, and liver metastases from colorectal cancer patients

BACKGROUND: Colorectal cancer (CRC) is one of the most common causes of cancer-related deaths in the Western world, and despite the fact that metastases are usually the ultimate cause of deaths, the knowledge of the genetics of advanced stages of this disease is limited. In order to identify potential genetic abnormalities underlying the development of local and distant metastases in CRC patients,

The nature of super-metal-rich stars. Detailed abundance analysis of 8 super-metal-rich star candidates

We provide detailed abundance analyses of 8 candidate super-metal-richstars. Five of them are confirmed to have [Fe/H]>0.2 dex, thegenerally-accepted limit for super-metal-richness. Furthermore, wederive abundances of several elements and find that the stars followtrends seen in previous studies of metal-rich stars. Ages are estimatedfrom isochrones and velocities calculated. We find that there do

Perceptions of the real and the ideal ward atmosphere among trainees and staff before and after the introduction of a new work rehabilitation model

Changes in the ward atmosphere of a psychiatric work rehabilitation unit were investigated. Both trainees and staff filled in the Community-Oriented Programs Environment Scale (COPES) before and after a new rehabilitation model was implemented. It was hypothesised that the levels of autonomy and practical orientation would increase from both the trainees' and staff's perspective concerning the rea

Development of a Multidimensional Residual Distribution Solver for Large Eddy Simulation of Industrial Turbulent Flows.

Popular Abstract in Swedish Utveckling av en flerdimensionell residual-distributions lösare för Large Eddy Simulation av industriell turbulenta strömningar.This thesis presents the results of the author's research activity to develop a time-space accurate flow-solver for Large Eddy Simulations (LES), based on the Multidimensional Residual Distribution approach. The aim of this work is the attempt to develop a compact high-order algorithm which includes multidimensional flow physics, in hope of creating a better algorithm for LES of turbulent compress

Buildings and Energy - a systematic approach

In many existing buildings, energy conservation measures have significantly reduced the demands for heat supply. In new buildings, advances in a wide range of technologies have led to even greater reductions. On the other hand, demands for electrical energy have risen noticeably. Unfortunately, it now seems that the use of both heat and electrical energy is starting to increase, especially in non

Atomic-scale visualization of inertial dynamics

The motion of atoms on interatomic potential energy surfaces is fundamental to the dynamics of liquids and solids. An accelerator-based source of femtosecond x-ray pulses allowed us to follow directly atomic displacements on an optically modified energy landscape, leading eventually to the transition from crystalline solid to disordered liquid. We show that, to first order in time, the dynamics ar

Regional differences in mechanical properties between major arteries--an experimental study in sheep

PURPOSE: To study possible differences in mechanical properties between central (abdominal aorta) and more peripheral (common carotid and common femoral) arteries validating an earlier non-invasive study in children showing that central arteries are more distensible than peripheral ones. As invasive blood pressure was needed, but ethically impossible to obtain in children in an experimental settin

A dynamic analysis of the oscillations in a chain drive

A model is presented in which the oscillations, and the forces thus produced, in a chain drive, working at moderate and high speed, can be calculated. Since the outer system affects the result it has been necessary to include this in the model. The mass of the chain is included in the model and both the gravitational forces and the inertia forces in the chain are taken into account. The elasticity

The relationship between different forms of human alpha-mannosidase

The tissue distribution and some properties of human alpha-mannosidase (alpha-D-mannoside mannohydrolase EC 3.2.1.24) have been studied. The acidic forms of the enzyme were fairly stable, whereas the neutral forms easily lost enzymic activity. The acidic forms were sensitive to neuraminidase but the neutral forms were unaffected. The experiments indicate that the acidic components are closely rela

Country of origin, social support and the risk of small for gestational age birth.

Aims: This study investigates the risk of small for gestational age (SGA) in relation to country of origin of the mother. The role of psychosocial resources, socioeconomic and lifestyle factors was examined in different causal models. Methods: Among all pregnant nulliparous women in the city of Malmo¨ , Sweden, who gave birth in 1991 – 92, 872 (87.7%) women completed a questionnaire during their f

T cell responses to a non-glycosylated epitope predominate in type II collagen-immunised HLA-DRB1*0101 transgenic mice

Aim: To study collagen-induced arthritis in human leucocyte antigen (HLA)-DR1 transgenic mice lacking endogenous major histocompatibility complex class II molecules (MHC-II) and to determine T cell specificity against the arthritogenic CII259-273 epitope of type II collagen either unmodified or post-translationally glycosylated at Lys(264). Methods: Arthritis was induced by immunisation with human

Endothelial proliferation and increased blood-brain barrier permeability in the basal ganglia in a rat model of 3,4-dihydroxyphenyl-L-alanine-induced dyskinesia.

3,4-Dihydroxyphenyl-(L)-alanine ((L)-DOPA)-induced dyskinesia is associated with molecular and synaptic plasticity in the basal ganglia, but the occurrence of structural remodeling through cell genesis has not been explored. In this study, rats with 6-hydroxydopamine lesions received injections of the thymidine analog 5-bromo-2'-deoxyuridine (BrdU) concomitantly with (L)-DOPA for 2 weeks. A large

The new cell irradiation facility at the Lund nuclear probe

The CELLION project is directed towards the studies on cellular response to targeted single ions. This paper gives an account of the modifications made at the Lund sub-micron beam line in order to create a Single Ion Hit Facility for biological applications within the CELLION project. The most relevant new feature is the specially developed software used to locate the cells. A program for cell rec

Quantum computer hardware based on rare-earth-ion-doped inorganic crystals

We present a scheme for generating multiple, strongly interacting qubits in rare-earth-ion-doped inorganic crystals at cryogenic temperatures. Two ground state hyperfine levels, with hour long lifetimes and ms decoherence times are chosen as qubit states. Controlled logic between the qubits is accomplished using the change in permanent dipole moment induced by an optical transition between the gro