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Gaia Data Release 1 : Reference frame and optical properties of ICRF sources

Context. As part of the data processing for Gaia Data Release 1 (Gaia DR1) a special astrometric solution was computed, the so-called auxiliary quasar solution. This gives positions for selected extragalactic objects, including radio sources in the second realisation of the International Celestial Reference Frame (ICRF2) that have optical counterparts bright enough to be observed with Gaia. A subs

Distributions at random events

We discuss the generalized Rice formula approach to deriving long-run distributions of characteristics defined at random events of a stochastic process or field. The approach stems from the same principle originally introduced by Rice for the level crossing intensity in a random signal and we review its extensions to more general contexts. Events are defined on random surfaces through crossing lev

DrAST: an inspection tool for attributed syntax trees (tool demo)

When implementing a language by means of attribute grammars, it is often useful to study example programs and their attributed trees, to understand the compiler structure, or for debugging. DrAST is a tool that allows interactive inspection of attributed trees. It is interfaced to the JastAdd metacompiler, and supports all JastAdd attribution mechanisms, such as demand evaluation, reference attrib

Rope Hadronization, Geometry and Particle Production in pp and pA Collisions

Et af de mest interessante spørgsmål en fysiker kan forsøge at svare på er hvad består tingene af?. Et hus kan skilles ad i mursten, og murstenen kan også skilles ad i sine bestanddele.Sådan kan man fortsætte indtil man bare har atomer tilbage. Atomerne kan skilles ad ielektroner og en atomkerne der består af neutroner og protoner. Elektronen er, så vidt vived, fundamental, og kan ikke skilles ad.This thesis concerns models of high energy collisions of sub-atomic particles, and the models’ implementation in numerical simulations; so–called Monte Carlo event generators. The models put forth in the thesis improves the description of soft collisions of protons, and takes the first steps towards a new, microscopic description of collectivity in proton collisions and collisions of heavy nuclei

Distributions of spatial wave size for random fields

A method of measuring three-dimensional spatial wave size is proposed and statistical distributions of the size characteristics are derived in explicit integral forms for Gaussian sea surfaces. New definitions of wave characteristics such as the crest-height, the length, the size and the wave front location are provided in fully dimensional context. The joint statistical distributions of these wav

Finite Length Weight Enumerator Analysis of Braided Convolutional Codes

Braided convolutional codes (BCCs) are a class of spatially coupled turbo-like codes (SC-TCs) with excellent belief propagation (BP) thresholds. In this paper we analyze the performance of BCCs in the finite block-length regime. We derive the average weight enumerator function (WEF) and compute the union bound on the performance for the uncoupled BCC ensemble. Our results suggest that the union bo

Main nutrient patterns are associated with prospective weight change in adults from 10 European countries

Purpose: Various food patterns have been associated with weight change in adults, but it is unknown which combinations of nutrients may account for such observations. We investigated associations between main nutrient patterns and prospective weight change in adults. Methods: This study includes 235,880 participants, 25–70 years old, recruited between 1992 and 2000 in 10 European countries. Intake

News Media and the Öresund Region. A Case of Horizontal Europeanisation?

This article presents a first attempt to investigate the news content and news routines of Danish and Swedish news media covering the Öresund region. From a theoretical perspective, the Öresund region can be considered a possible best-case example of what is categorised as horizontal Europeanisation, in other words, of the potential for increased communication linkages in news media content among This article presents a first attempt to investigate the news content and news routines of Danish and Swedish news media covering the Öresund region. From a theoretical perspective, the Öresund region can be considered a possible best-case example of what is categorised as horizontal Europeanisation, in other words, of the potential for increased communication linkages in news media content among

First application of superconducting transition-edge sensor microcalorimeters to hadronic atom X-ray spectroscopy

High-resolution pionic atom X-ray spectroscopy was performed with an X-ray spectrometer based on a 240 pixel array of superconducting transition-edge sensor (TES) microcalorimeters at the φM1 beam line of the Paul Scherrer Institute. X-rays emitted by pionic carbon via the 4f → 3d transition and the parallel 4d → 3p transition were observed with a full width at half maximum energy resolution of 6.

Biomarkers of exposure to pesticides in humans

Idag används årligen över 2 miljoner ton bekämpningsmedel (BM) i världen. Avdessa står Sverige för drygt 9000 ton, eller knappt en halv procent. Den häravhandlingen handlar om att ta fram metoder för att bestämma rester av vissabekämpningsmedel i kroppsvätskor (urin) hos människor och sedan användametoderna för att mäta exponering för bekämpningsmedlen i en befolkningsgrupp. Arbetet är en del av fAlmost every human is exposed to pesticides, in work environments, by domestic use and via diet, drinking water and personal products. Current research expresses concern that low dose exposure over time can lead to adverse health effects. It is therefore important to biomonitor exposure to pesticides in different groups, especially vulnerable groups such as pregnant women. However, there is a gene

An Intense Attosecond Light Source - from Generation to Application

Short and intense XUV pulses are important tools to study ultrafast dynamics and non-linear processes in matter. These pulses can be generated by free electron lasers (FELs) or by high-order harmonic generation (HHG), which are two complementary techniques. The advantage of HHG is the possibility to generate pulses with durations on the attosecond timescale, but the low conversion efficiency of th

Prevention of stroke : A strategic global imperative

The increasing global stroke burden strongly suggests that currently implemented primary stroke prevention strategies are not sufficiently effective, and new primary prevention strategies with larger effect sizes are needed. Here, we review the latest stroke epidemiology literature, with an emphasis on the recently published Global Burden of Disease 2013 Study estimates; highlight the problems wit

Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes

Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neut

New lifetime measurements in the stable semimagic Sn isotopes using the Doppler-shift attenuation technique

Precise measurements of lifetimes in the picosecond range of excited states in the stable even-A Sn isotopes 112,114,116,122Sn have been performed using the Doppler shift attenuation technique. For the first excited 2+ states in 112Sn, 114Sn and 116Sn the E2 transition strengths deduced from the measured lifetimes are in disagreement with the previously adopted values. They indicate a shallow mini

β decay of26Ne

A pure neutron-rich 26Ne beam was obtained at the ISOLDE facility using isobaric selectivity. This was achieved by a combination of a plasma ion source with a cooled transfer line and subsequent mass separation. The high quality of the beam and good statistics allowed us to obtain new experimental information on the 26Ne β-decay properties and resolve a contradiction between earlier experimental d

Role of Insulinlike Growth Factor 1 in Fetal Development and in the Early Postnatal Life of Premature Infants

The neonatal period of very preterm infants is often characterized by a difficult adjustment to extrauterine life, with an inadequate nutrient supply and insufficient levels of growth factors, resulting in poor growth and a high morbidity rate. Long-term multisystem complications include cognitive, behavioral, and motor dysfunction as a result of brain damage as well as visual and hearing deficits

The Opportunity Offered by the ESSnuSB Project to Exploit the Larger Leptonic CP Violation Signal at the Second Oscillation Maximum and the Requirements of This Project on the ESS Accelerator Complex

The European Spallation Source (ESS), currently under construction in Lund, Sweden, is a research center that will provide, by 2023, the world's most powerful neutron source. The average power of the proton linac will be 5 MW. Pulsing this linac at higher frequency will make it possible to raise the average total beam power to 10 MW to produce, in parallel with the spallation neutron production, a

Low-energy Coulomb excitation of 62Fe and 62Mn following in-beam decay of 62Mn

Sub-barrier Coulomb excitation was performed on a mixed beam of 62Mn and 62Fe, following in-trap β− decay of 62Mn at REX-ISOLDE, CERN. The trapping and charge breeding times were varied in order to alter the composition of the beam, which was measured by means of an ionisation chamber at the zero-angle position of the Miniball array. A new transition was observed at 418 keV, which has been tentati

β- decay of the neutron-rich isotope 215Pb

This Brief Report reports on the first observation of the β--delayed γ decay of 215Pb, feeding states in 215Bi. The 215Pb beam was produced using resonant laser ionization and mass separated at the ISOLDE-CERN on-line mass separator. This ensured clean identification of the γ rays as belonging to the decay of 215Pb or its β-decay daughters. A half-life of 147(12) s was measured for the 215Pb β dec