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Nonadiabaticity of cavity-free neutral nitrogen lasing

We report on a theoretical study of cavity-free lasing of neutral nitrogen molecules in femtosecond laser filaments with a nonadiabatic Maxwell-Bloch model, compared with recent pump-seed experiments. The nonadiabaticity of the lasing process is revealed and it is found that electron-neutral collisions dominate the dipole dephasing rate. Moreover, we show that the asymmetry between forward and bac

On the thermal degradation of tunnel diodes in multijunction solar cells

Tunnel junctions are essential components of multijunction solar cells. These highly doped p/n junctions provide the electrical interconnect between the subcells that constitute a multijunction solar cell device. The conductivity and the peak tunneling current of tunnel diodes are known to be severely affected by thermal load. This is a general phenomenon observed in tunnel junctions despite the m

Improved scatter correction with factor analysis for planar and SPECT imaging

Quantitative nuclear medicine imaging is an increasingly important frontier. In order to achieve quantitative imaging, various interactions of photons with matter have to be modeled and compensated. Although correction for photon attenuation has been addressed by including x-ray CT scans (accurate), correction for Compton scatter remains an open issue. The inclusion of scattered photons within the

Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars : VI. Age and abundance structure of the stellar populations in the central sub-kpc of the Milky Way

We present a detailed elemental abundance study of 90 F and G dwarf, turn-off, and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11 elements (Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Zn, Y and Ba) have been determined. Four main findings are presented: (1) a wide metallicity distribution with distinc

Altered expression of CD1d molecules and lipid accumulation in the human hepatoma cell line HepG2 after iron loading

Iron overload in the liver may occur in clinical conditions such as hemochromatosis and nonalcoholic steatohepatitis, and may lead to the deterioration of the normal liver architecture by mechanisms not well understood. Although a relationship between the expression of ICAM-1, and classical major histocompatibility complex (MHC) class I molecules, and iron over-load has been reported, no relations

NOX2-dependent immunosuppression in chronic myelomonocytic leukemia

Chronic myelomonocytic leukemia (CMML) is a myeloproliferative and myelodysplastic neoplasm with few treatment options and dismal prognosis. The role of natural killer (NK) cells and other antileukemic lymphocytes in CMML is largely unknown. We aimed to provide insight into the mechanisms of immune evasion in CMML with a focus on immunosuppressive reactive oxygen species (ROS) formed by the myeloi

Singing the body electric : Understanding the role of embodiment in performing and composing interactive music

Almost since the birth of electronic music, composers have been fascinated by the prospect of integrating the human voice with its expressiveness and complexity into electronic musical works. This thesis addresses how performing with responsive technologies in mixed works, i.e. works that combine an acoustic sound source with a digital one, is experienced by participating singers,adopting an appro

Influence of radial depth of cut on entry conditions and dynamics in face milling application

The choice of milling cutter geometry and appropriate cutting data for certain milling application is of vital importance for successful machining results. Unfavorable selection of cutting conditions might give rise to high load impacts that cause severe cutting edge damage. Under some circumstances the radial depth of cut in combination with milling cutter geometry might give unfavorable entry co

Treatment with direct oral anticoagulants in patients with upper extremity deep vein thrombosis

Background: Upper extremity deep vein thrombosis (UEDVT) constitutes around 10% of all DVT, and can cause both pulmonary embolism (PE) and postthrombotic syndrome (PTS) in the arm. The incidence of secondary UEDVT is increasing due to widespread use of central venous catheters in patients with cancer and other chronic diseases. The safety and efficacy of using new direct acting oral anti coagulant

Plasma l-arginine levels distinguish pulmonary arterial hypertension from left ventricular systolic dysfunction

Pulmonary arterial hypertension (PAH) is a life-threatening condition, characterized by an imbalance of vasoactive substances and remodeling of pulmonary vasculature. Nitric oxide, formed from l-arginine, is essential for homeostasis and smooth muscle cell relaxation in PAH. Our aim was to compare plasma concentrations of l-arginine, asymmetric dimethylarginine (ADMA), and symmetric dimethylargini

Variability and quasi-decadal changes in the methane budget over the period 2000-2012

Following the recent Global Carbon Project (GCP) synthesis of the decadal methane (CH4) budget over 2000-2012 (Saunois et al., 2016), we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH4 emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework) and bottom-

A chronology of environmental changes in the Lake Vättern basin from deglaciation to its final isolation

During and after deglaciation, Lake Vättern developed from a proglacial lake situated at the westernmost rim of the Baltic Ice Lake (BIL), into a brackish water body connecting the North Sea and the Baltic Sea, and finally into an isolated freshwater lake. Here we present geochemical and mineralogical data from a 70-m composite sediment core recovered in southern Lake Vättern. Together with a radi