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Physics of attosecond pulses produced via high harmonic generation

The physics of extreme ultraviolet attosecond pulse trains generated during the interaction between an intense laser pulse and a gas medium is presented, including a simple model based on the solution of the classical equations of motion of an electron in an oscillating laser field. The reconstruction of attosecond beating by the interference of a two-photon transition is described and used to det

Bleeding and first-year mortality following hip fracture surgery and preoperative use of low-dose acetylsalicylic acid: an observational cohort study

Background: Hip fracture is associated with high mortality. Cardiovascular disease and other comorbidities requiring long-term anticoagulant medication are common in these mostly elderly patients. The objective of our observational cohort study of patients undergoing surgery for hip fracture was to study the association between preoperative use of low-dose acetylsalicylic acid (LdAA) and intraoper

Vibrationally resolved resonant inelastic soft X-ray scattering spectra of free molecules

The brilliance of modern synchrotron radiation sources and capabilities of new instrumentation facilitate molecular resonant inelastic soft X-ray scattering with high spectral quality. Especially, energy resolution of vibrational fine structure allows for a detailed analysis, providing information about the dynamic coupling between nuclear and electronic degrees of freedom. After a brief historica

Morphometric Differences between the Medial and Lateral Meniscus in Healthy Men - A Three-Dimensional Analysis Using Magnetic Resonance Imaging

The objective of this work was to characterize tibial plateau coverage and morphometric differences of the medial (MM) and lateral meniscus (LM) in a male reference cohort using three-dimensional imaging. Coronal multiplanar reconstructions of a sagittal double-echo steady state with water excitation magnetic resonance sequence (slice thickness: 1.5 mm, and in-plane resolution: 0.37 x 0.70 mm) wer

Formation and consumption of NO in H-2 + O-2 + N-2 flames doped with NO or NH3 at atmospheric pressure

Flat premixed burner-stabilized H-2 + O-2 + N-2 flames, neat or doped with 300-1000 ppm of NO or NH3, were studied experimentally using molecular-beam mass-spectrometry and simulated numerically. Spatial profiles of temperature and concentrations of stable species, H-2, O-2, H2O, NO, NH3, and of H and OH radicals obtained at atmospheric pressure in lean (phi = 0.47), near-stoichiometric (phi = 1.1

The Nordic medical birth registers - a potential goldmine for clinical research

The Nordic medical birth registers have long been used for valuable clinical research. Their collection of data for more than four decades offers unusual possibilities for research across generations. At the same time, serum and blotting paper blood samples have been stored from most neonates. Two large cohorts (approximately 100000 births) in Denmark and Norway have been described by questionnair

Reasons and Two Kinds of Fact

Reasons are facts, i.e., they are constituted by facts. This “reason quo fact” claim is much endorsed in recent literature. This paper addresses some issues that arise when we apply this idea to the distinction between agent-neutral and agent-relative normative reasons. I shall mainly consider two views of the nature of facts. Given a popular view, which conceives of facts as abstract entities, th

Microwaves from Mobile Phones Inhibit 53BP1 Focus Formation in Human Stem Cells More Strongly Than in Differentiated Cells: Possible Mechanistic Link to Cancer Risk

BACKGROUND: It is widely accepted that DNA double-strand breaks (DSBs) and their misrepair in stem cells are critical events in the multistage origination-of various leukemias and tumors, including gliomas. OBJECTIVES: We studied whether microwaves from mobile telephones of the Global System for Mobile Communication (GSM) and the Universal Global Telecommunications System (UMTS) induce DSBs or aff

Who suffers from unemployment? The role of health and skills

Unemployment swings have distributional consequences if some groups are hit harder than others. We examine if the sensitivity to local unemployment rates varies by characteristics such as health, cognitive ability and non-cognitive ability. Data on these variables come from registers covering the entire Swedish population of males. We show that variations in the unemployment rate are associated wi

Depression in Dercum's disease and in obesity: A case control study

Background: Dercum's disease is characterised by pronounced pain in the adipose tissue and a number of associated symptoms. The condition is usually accompanied by generalised weight gain. Many of the associated symptoms could also be signs of depression. Depression in Dercum's disease has been reported in case reports but has never been studied using an evidence-based methodology. The aim of this

Agreement of two-dimensional and three-dimensional transvaginal ultrasound with magnetic resonance imaging in assessment of parametrial infiltration in cervical cancer

Objectives To compare two-dimensional (2D) and three-dimensional (3D) transvaginal ultrasound with magnetic resonance imaging (MRI) as the gold standard in assessment of parametrial infiltration of cervical cancer and to determine if all parts of the cervix are equally assessable with ultrasound. Methods Patients with macroscopically evident and histologically confirmed cervical cancer were staged

Massive MIMO in Real Propagation Environments: Do All Antennas Contribute Equally?

Massive MIMO can greatly increase both spectral and transmit-energy efficiency. This is achieved by allowing the number of antennas and RF chains to grow very large. However, the challenges include high system complexity and hardware energy consumption. Here we investigate the possibilities to reduce the required number of RF chains, by performing antenna selection. While this approach is not a ve

Structure changes in Er-160 from low to ultrahigh spin

A spectroscopic investigation of the gamma decays from excited states in Er-160 has been performed in order to study the changing structural properties exhibited from low spin up toward ultrahigh spin (I similar to 60 h). The nucleus Er-160 was populated by the reaction Cd-116(Ca-48,4n gamma) at a beam energy of 215 MeV, and resulting gamma decays were studied using the Gammasphere spectrometer. N

Laminar burning velocities of n-heptane, iso-octane, ethanol and their binary and tertiary mixtures

Measurements of the adiabatic laminar burning velocities of n-heptane, iso-octane, ethanol and their binary and tertiary mixtures are reported. Non-stretched flames were stabilized on a perforated plate burner at 1 atm. The Heat Flux method was used to determine burning velocities under conditions when the net heat loss from the flame to the burner is zero. Initial temperatures of the gas mixtures

The Ferrum project: experimental and theoretical transition rates of forbidden [Sc II] lines and radiative lifetimes of metastable Sc II levels

Context. In many plasmas, long-lived metastable atomic levels are depopulated by collisions (quenched) before they decay radiatively. In low-density regions, however, the low collision rate may allow depopulation by electric dipole (E1) forbidden radiative transitions, so-called forbidden lines (mainly M1 and E2 transitions). If the atomic transition data are known, these lines are indicators of p

On Microstructural Analysis of Porous Media Existing in Fuel Cells Using the Lattice Boltzmann Method

This Licentiate thesis aims to gain understanding related to the fluid behavior in porous media existent in fuel cells (FCs) at microscale. In order to achieve this; the widely used methodology for solving problems in porous media has been applied, the Lattice Boltzmann Method (LBM). LBM presents several advantages to solve problems where the microstructural architecture is complex. The introduc