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Diffusion är den slumpmässiga rörelse hos partiklar som drivs av deras kinetiska energi. Den är oftast osynlig för blotta ögat, men den utgör en viktig funktion för vår överlevnad. Diffusionen står bland annat för transporten av näringsämnen över cellmembran, och det är diffusionen som gör att ämnen i kroppen blandas så att livsviktiga kemiska reaktioner kan ske.Man kan undersöka diffusionsprocessDiffusion MRI provides a non-invasive probe of tissue microstructure. We recently proposed a novel method for diffusion-weighted imaging, so-called q-space trajectory encoding, that facilitates tensor-valued diffusion encoding. This method grants access to b-tensors with multiple shapes and enables us to probe previously unexplored aspects of the tissue microstructure. Specifically, we can disenta

A deep understanding of the behavior of microstructural parameters in proton exchange fuel cells (PEFCs) will help to reduce the material cost and to predict the performance of the device at cell scale. Changes in morphological configuration, that is, fiber diameter and fiber orientation, of the gas diffusion layers (GDLs) result in variations of fluid behavior throughout the layer, and therefore,

In the course of my PhD work, I have been involved in the development and the construction of the Tagging System for the BGO-OD experiment at the ELSA accelerators of the University of Bonn.BGO-OD is a fixed target experiment for the investigation of the structure of the nucleon at low energies via the photoproduction of mesons. It consist of a central calorimeter and a forward spectrometer. The r

The BGO-OD experiment is intended for the systematic investigation of the photo-production of mesons off the nucleon. The experiment will use bremsstrahlung photons from an e- beam incident upon a thin radiator. The photon energy will be measured via the deflection of the electrons in the magnetic field of a photon tagger. The B-FrED is a 16 channel double-threshold discriminator and shaper board

The LHCb Muon System consists of 122000 front-end channels, distributed on about 8000 front-end boards (on detector). 152 Off detector boards (each containing 192 channels) gather information from front-end and send it to the DAQ and trigger systems. The Muon System is highly configurable and is conceived to allow a deep control of the behavior of the whole system during data taking. This results

The LHCb system requires high efficiency muon detection into LHC bunch crossing: 95% into a 25 ns time window. To reach such efficiency many parameters of the detector readout apparatus have to be calibrated and adjusted and its channels must be aligned in time. In addition, essential characteristics must be monitored to guarantee a good working condition of the apparatus (to avoid loss of efficie

The LHCb experiment, presently under construction at CERN (European Center for Nuclear Research) Large Hadron Collider (LHC), aims at the study of CP violation in the B meson sector. Its key elements will be a Muon detector which allows triggering and muon identification from inclusive b decays. The electronic system of the whole detector is very complex and its Muon detector Experiment Control Sy

The LHCb muon readout apparatus is made of 1368 Multi-Wire Proportional Chambers (MWPC) and 24 Gas Electron Multiplier (GEM) chambers connected to 7632 16-channel front-end boards, resulting in 122.112 channels to be read out. After a pp collision, all the resulting signals must be read within 25 ns, before the next collision. The large-scale of the system and the time constrains naturally led to

The BGO Rugby Ball is a large solid angle electromagnetic calorimeter now installed in the ELSA Facility in Bonn. The BGO is operating in the BGO-OD experiment aiming to study meson photoproduction off proton and neutron induced by a Bremsstrahlung polarized gamma beam of energies from 0.2 to 3.2 GeV and an intensity of 5 × 107 photons per second. The scintillating material characteristics and the

The results obtained at the BGO-OD experiment with the BGO calorimeter, equipped with the new electronic readout based on sampling ADCs, during the tests performed with the beam time of March and June 2012 are presented. The proper functioning of the apparatus has allowed the reconstruction of the pseudo-scalar mesons π0 and η invariant masses. The simulation of the η' photoproduction reaction pre

In North Sámi, verbs that form transitivity alternation pairs are always distinguished morphologically. However, even if morphology is seen as a reflex of the syntax, the syntactic structure underlying transitive and intransitive verbs in North Sámi cannot be directly read off from the morphology. Since the verbalisers have vocalic phonological realisations with some roots but consonantal realisat

In late 2016, Lund is on the verge of becoming the center of accelerator-based material science in Europe.The MAX IV Laboratory, an electron synchrotron, was inaugurated in June 2016 with a scientific program to commence shortly and the European Spallation Source ERIC (ESS), a spallation neutron source, is presently under construction and anticipated to be fully operational by 2022.These facilitiThe He-3 “crisis” has become a fact in the last decade and large scale neutron detectors based on He-3 technologies have become unaffordable. This new He-3 reality has resulted in a major effort worldwide to develop replacement neutron-detector technologies. Many of these technologies are in their infancy and need to be thoroughly tested before becoming mainstream, while others are approaching co

X-ray photoelectron emission microscopy (XPEEM) was used in combination with other microscopic and spectroscopic techniques to follow the surface development of an aluminum brazing sheet during heating. The studied aluminum alloy sheet is a composite material designed for vacuum brazing. Its surface is covered with a native aluminum oxide film. Changes in the chemical state of the alloying element

The Swedish alternative movement’s place-making activities in the seventies have been understood as an attempt to escape the political sphere. In this thesis, I investigate the ideas and practices of societal transformation seen in rural intentional communities and, to a lesser degree, urban sites. Challenging the idea that such intentional communities were solely concerned with the creation of ‘p

Background: General Practitioners (GPs) are responsible for primary prescribing decisions in most settings. Elderly patients living in Advanced Care Facilities (ACFs) often have significant co-morbidities to consider when selecting an appropriate drug therapy. Careful assessment is required when considering appropriate medication use in frail older patients as they have multiple diseases and thus

Background: Detection of atrial fibrillation after ischemic stroke is challenging due to its paroxysmal nature. We aimed to assess predictors of paroxysmal atrial fibrillation using non-invasive surface ECG and transthoracic echocardiography to select candidates for atrial fibrillation screening. Methods: Ischemic stroke patients without documented atrial fibrillation (n = 110, 67 ± 10 years, 40 f

Purpose To study prevalence of diabetic retinopathy (DR) at diagnosis (DRAD) and to estimate contributing risk by sociodemographic, cardiovascular and metabolic characteristics present in patients recently diagnosed with type 2 diabetes (T2D) or latent autoimmune diabetes in the adult (LADA). Methods Patients (n = 2174) recently diagnosed T2D (93%) or LADA (7%) were included upon arrival for their

Approximately 80%-90% of all fire-related fatalities take place in residential occupancies. The risk groups are well known, but the effectiveness of different measures has been less investigated. In this article, fire investigations from 144 unintentional fatal residential fires have been systematically analyzed and technical measures that would have been effective in preventing each fatality have

Background: Inositol trispyrophosphate (ITPP) has been shown to reduce tumour growth in different animal cancer models, as well as of human U87 glioma cells grafted onto chick chorioallantoic membrane (CAM). The aim of this study was to establish whether ITPP crosses the blood-brain barrier and whether it halts the growth of RG2 glioblastoma tumour. Materials and Methods: A model comprising of Fis