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Supersonic jets of hydrogen and helium for laser wakefield acceleration

The properties of laser wakefield accelerated electrons in supersonic gas flows of hydrogen and helium are investigated. At identical backing pressure, we find that electron beams emerging from helium show large variations in their spectral and spatial distributions, whereas electron beams accelerated in hydrogen plasmas show a higher degree of reproducibility. In an experimental investigation of

Understanding the complex metallic element Mn. II. Geometric frustration in β−Mn, phase stability, and phase transitions

In the preceding paper [D. Hobbs, J. Hafner, and D. Spišák, Phys. Rev. B 68, 014407 (2003)], we have started an ab initio spin-density-functional study of the complex structural and magnetic phase behaviors of Mn by a detailed investigation of α−Mn. It was shown that the complex crystalline and noncollinear antiferromagnetic structures are the results of the conflicting tendencies to maximize simu

ICARUS -- An Extensible Graphical Search Tool for Dependency Treebanks

We present ICARUS, a versatile graphical search tool to query dependency treebanks. Search results can be inspected both quantitatively and qualitatively bymeans of frequency lists, tables, or dependency graphs. ICARUS also ships with plugins that enable it to interface with tool chains running either locally or remotely.

Novel tenascin variants with a distinctive pattern of expression in the avian embryo

Previous studies have shown that several forms of the glycoprotein tenascin are present in the embryonic extracellular matrix. These forms are the result of alternative splicing, which generates tenascin variants with different numbers of fibronectin type III repeats. We have used degenerate primers and PCR to isolate a novel tenascin exon from an avian genomic library. Genomic clones contained a

One Moment in Time-Modeling Star Formation in the Antennae

We present a new high-resolution N-body/smoothed particle hydrodynamics simulation of an encounter of two gas-rich disk galaxies that closely matches the morphology and kinematics of the interacting Antennae galaxies (NGC 4038/39). The simulation includes radiative cooling, star formation, and feedback from Type II supernovae. The large-scale morphology and kinematics are determined by the interna

AkuLite - A research project to strengthen light weight structures

In Sweden a new research project started in December 2009. The project focuses on light weight constructions and its sound insulation characteristics with respect to subjective response, and it will be carried out during the period of December 2009 to December 2012. The main goal is to develop new evaluation criteria proposals, for the low frequency range and vibrations and their mutual interactio

Effect of molecular weight of polyacrylic acid (PAA) on polyethersulfone membrane structure and performance

The novel method of modification of polyethersulfone (PES) ultrafiltration membranes is proposed. This method involves the use of aqueous solutions of polyacrylic acid (PAA) of different molecular weights (Mn=5.1×103 g·mol–1, Mn=490×103 g·mol–1) as a coagulant in non-solvent induced phase inversion process (NIPS). Addition of PAA (0.05–1.5 wt%) to the coagulation bath leads to marked changes in pe

High Electron Mobility and Insights into Temperature-Dependent Scattering Mechanisms in InAsSb Nanowires

InAsSb nanowires are promising elements for thermoelectric devices, infrared photodetectors, high-speed transistors, as well as thermophotovoltaic cells. By changing the Sb alloy fraction the mid-infrared bandgap energy and thermal conductivity may be tuned for specific device applications. Using both terahertz and Raman noncontact probes, we show that Sb alloying increases the electron mobility i

Decadal-scale progression of the onset of Dansgaard-Oeschger warming events

During the last glacial period, proxy records throughout the Northern Hemisphere document a succession of rapid millennial-scale warming events, called Dansgaard-Oeschger (DO) events. A range of different mechanisms has been proposed that can produce similar warming in model experiments; however, the progression and ultimate trigger of the events are still unknown. Because of their fast nature, th

NLOX, a one-loop provider for Standard Model processes

NLOX is a computer program for calculations in high-energy particle physics. It provides fully renormalized scattering matrix elements in the Standard Model of particle physics, up to one-loop accuracy for all possible coupling-power combinations in the strong and electroweak couplings, and for processes with up to six external particles.

High Plasma sRAGE (Soluble Receptor for Advanced Glycation End Products) Is Associated With Slower Carotid Intima-Media Thickness Progression and Lower Risk for First-Time Coronary Events and Mortality

Objective- RAGE (receptor for advanced glycation end products) and EMMPRIN (extracellular matrix metalloproteinase inducer) are immune receptors for proinflammatory mediators. These receptors can also be found in a soluble form in the circulation. Soluble RAGE (sRAGE) has shown atheroprotective properties in animal studies, possibly by acting as a decoy receptor for its ligands. Whether sEMMPRIN (

Towards Robust Linguistic Analysis using OntoNotes

Large-scale linguistically annotated corpora have played a crucial role in advancing the state of the art of key natural language technologies such as syntactic, semantic and discourse analyzers, and they serve as training data as well as evaluation benchmarks. Up till now, however, most of the evaluation has been done on monolithic corpora such as the Penn Treebank, the Proposition Bank. As a res

The discoidin domain family revisited : new members from prokaryotes and a homology-based fold prediction

Members of the discoidin (DS) domain family, which includes the C1 and C2 repeats of blood coagulation factors V and VIII, occur in a great variety of eukaryotic proteins, most of which have been implicated in cell-adhesion or developmental processes. So far, no three-dimensional structure of a known example of this extracellular module has been determined, limiting the usefulness of identifying a