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Climate change, energy security and air pollution are all motivators for the further development of fuel cells. A volume of fluid approach was used to investigate the impact of dynamic contact angle boundary conditions (Kistler model), mainly at the gas diffusion layer surface but also at the channel wall, of a polymer electrolyte fuel cell gas channel. From this study, it is clear that a dynamic

Background: Supratentorial intracerebral haemorrhage (ICH) carries an excessive mortality and morbidity. Although surgical ICH treatment can be life-saving, the indications for surgery in larger cohorts of ICH patients are controversial and not well defined. We hypothesised that surgical indications vary substantially among neurosurgical centres in Sweden. Objective: In this nation-wide retrospect

This study focuses on drivers for changing urban flood risk. We suggest a framework for guiding climate change adaptation action concerning flood risk and manageability in cities. The identified key drivers of changing flood hazard and vulnerability are used to provide an overview of each driver's impact on flood risk and manageability at the city level. We find that identified drivers for urban f

The associations of individual dietary fatty acids with prostate cancer risk have not been examined comprehensively. We examined the prospective association of individual dietary fatty acids with prostate cancer risk overall, by tumor subtypes, and prostate cancer death. 142,239 men from the European Prospective Investigation into Cancer and Nutrition who were free from cancer at recruitment were

Background: Chronic pain patients frequently suffer from psychological symptoms. There is no consensus concerning the prevalence of severe anxiety and depressive symptoms and the strength of the associations between pain intensity and psychological distress. Although an important aspect of the clinical picture is understanding how the pain condition impacts life, little is known about the relative

Because of the scale of global displacement, in particular from Syria, the European Union has stressed the need to work on an effective asylum and immigration policy through more robust forms of cooperation internally, between Member States, and externally, with third countries. This contribution investigates the extent to which the EU rules for distributing asylum responsibilities genuinely addre

This thesis studies how humans and other social responsive animals can meet and get together as companion species and what role radical behaviorist B F Skinner’s learning theory and operant conditioning possibly can play in this. Drawing from theories of discourse and discourse analysis, social responsivity and companion species, the thesis analyzes what happens with Skinner’s learning theory when

Three injection strategies are compared in a light-duty (LD) diesel engine at a medium load point. One strategy, representative of a Euro 6 LD injection strategy, has a double-pilot/main/single-post sequence. There is a modest temporal spacing after the first pilot and second pilot. Additional strategies add a third pilot and greatly reduce the spacing after the pilots. These pilots are referred t

R. Johansson and M. Magnusson. Identification of human postural dynamics. Proc. IEEE Int. Conference on Control and Applications (ICCON '89), volume RP­-3­-6, pages 1--6, Jerusalem, Israel, 1989.

Two imaging techniques are used to investigate the interaction between developed combustion from earlier injections and partially oxidized fuel (POF) ofa subsequent injection. The latter is visualized by using planar laser induced fluorescence (PLIF) of formaldehyde and poly-cyclic aromatic hydrocarbons. High speed imaging captures the natural luminescence (NL) of the prevailing combustion. Three

Changes in combustion noise, eciency, and emissions are investigated as responses to boundary conditions and injection scheduling parameters of closely-coupled multiple-pilot strategies. The eects of pilot injection separation times, mixture dilution, and injection pressure are investigated. In order to minimize combustion noise, the heat release rate (HRR) should be as linear in its buildup as po

X-ray imaging techniques have proven invaluable to study biological systems at high resolution due to the penetration power and short wavelength of this radiation. In practice, the resolution and sensitivity of current X-ray imaging techniques are not limited by the performance of optics or image-recovery methods but by radiation damage. We propose the use of Compton (inelastic) X-ray scattering f

We report on a new contrast-transfer-function (CTF) phase-retrieval method based on the alternating direction method of multipliers (ADMMs), which allows us to exploit any compressed sensing regularization scheme reflecting the sparsity of the investigated object. The proposed iterative algorithm retrieves accurate phase maps from highly noisy single-distance projection microscopy data and is char

Multilayer Laue lenses are volume diffraction elements for the efficient focusing of X-rays. With a new manufacturing technique that we introduced, it is possible to fabricate lenses of sufficiently high numerical aperture (NA) to achieve focal spot sizes below 10 nm. The alternating layers of the materials that form the lens must span a broad range of thicknesses on the nanometer scale to achieve

The new European X-ray Free-Electron Laser is the first X-ray free-electron laser capable of delivering X-ray pulses with a megahertz inter-pulse spacing, more than four orders of magnitude higher than previously possible. However, to date, it has been unclear whether it would indeed be possible to measure high-quality diffraction data at megahertz pulse repetition rates. Here, we show that high-q

An X-ray grating interferometer (GI) suitable for clinical mammography must comply with quite strict dose, scanning time and geometry limitations, while being able to detect tumors, microcalcifications and other abnormalities. Such a design task is not straightforward, since obtaining optimal phase-contrast and dark-field signals with clinically compatible doses and geometrical constraints is rema

In X-ray grating interferometry, dark-field contrast arises due to partial extinction of the detected interference fringes. This is also called visibility reduction and is attributed to small-angle scattering from unresolved structures in the imaged object. In recent years, analytical quantitative frameworks of dark-field contrast have been developed for highly diluted monodisperse microsphere sus