AMBER : a near infrared focal instrument for the VLTI

10 pagesInternational audienceAMBER is the General User near-infrared focal instrument of the Very Large Telescope interferometer. Its specifications are based on three key programs on Young Stellar Objects, Active Galactic Nuclei central regions, masses and spectra of hot Extra Solar Planets. It has an imaging capacity because it combines up to three beams and very high accuracy measurement are expected from the spatial filtering of beams by single mode fibers and the comparison of measurements made simultaneously in different spectral channels

An asymmetry detected in the disk of Kappa CMa with the AMBER/VLTI

International audienceAims. We study the geometry and kinematics of the circumstellar environment of the Be star Kappa CMa in the Br gamma emission line and its nearby continuum. Methods. We use the VLTI/AMBER instrument operating in the K band which provides a spatial resolution of about 6 mas with a spectral resolution of 1500 to study the kinematics within the disk and to infer its rotation law. In order to obtain more kinematical constraints we also use an high spectral resolution Pa beta line profile obtain in December 2005 at the Observatorio do Pico do Dios, Brazil and we compile V/R line profile variations and spectral energy distribution data points from the literature. Results. Using differential visibilities and differential phases across the Br gamma line we detect an asymmetry in the disk. Moreover, we found that kappa CMa seems difficult to fit within the classical scenario for Be stars, illustrated recently by alpha Arae observations, i.e. a fast rotating B star close to its breakup velocity surrounded by a Keplerian circumstellar disk with an enhanced polar wind. Finally we discuss the possibility for kappa CMa to be a critical rotator with a Keplerian rotating disk and try to see if the detected asymmetry can be interpreted within the "one-armed" viscous disk framework

Un mezzo tremisse inedito di Eraclio I (610-641). Con annesso un catalogo dei mezzi tremissi ad oggi noti

Presentamos medio tremis inédito a nombre de Heraclio I y acuñado en R á vena.This paper aims to study a n unpublished half tremissis in the name of Heraclius I struck in Ravenna

Long-Lived Charge Separated State in NiO-Based p-Type Dye-Sensitized Solar Cells with Simple Cyclometalated Iridium Complexes

International audienc

A missing-mass spectrometer for momenta below 15 GeV/c

An apparatus consisting of two magnetic spectrometers has been constructed at the CERN Proton Synchrotron (PS) in a missing-mass experiment to identify and select the beam particle and the outgoing one, and to measure their momenta. The authors give details of the two spectrometers, which are comprised of multiwire proportional chambers, high resolution time-of-flight counters, and aerogel and water Cherenkov detectors. (9 refs)

Fatty acid acylated peptide therapeutics: discovery of omega-n oxidation of the lipid chain as a novel metabolic pathway in preclinical species

International audienceWe recently described C18 fatty acid acylated peptides as a new class of potent long-lasting single-chain RXFP1 agonists that displayed relaxin-like activities in vivo. Early pharmacokinetics and toxicological studies of these stearic acid acylated peptides revealed a relevant oxidative metabolism occurring in dog and minipig, and also seen at a lower extent in monkey and rat. Mass spectrometry combined to NMR spectroscopy studies revealed that the oxidation occurred, unexpectedly, on the stearic acid chain at ω-1, ω-2 and ω-3 positions. Structure-metabolism relationship studies on acylated analogues with different fatty acids lengths (C15-C20) showed that the extent of oxidation was higher with longer chains. The oxidized metabolites could be generated in vitro using liver microsomes and engineered bacterial CYPs. These systems were correlating poorly with in vivo metabolism observed across species; however, the results suggest that this biotransformation pathway might be catalyzed by some unknown CYP enzymes