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The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 represents about 22.000 users. It is composed of 30 member countries. Our vision is to support a thriving (European) synchrotron and FEL user community with equal opportunities of access and participation for all scientists, based solely on the scientific merit of their ideas.

The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 represents about 22.000 users. It is composed of 30 member countries. Our vision is to support a thriving (European) synchrotron and FEL user community with equal opportunities of access and participation for all scientists, based solely on the scientific merit of their ideas.

The European Synchrotron and free-electron laser User Organisation (ESUO) established in 2010 today represents about 30.000 users. We aim at representing the users from all European countries. Each country is represented within ESUO by one up to four national delegate(s), depending on the size of the user community in the respective country. The ESUO aims and activities are shown in this poster.

The magnetic correlations within the cuprates have undergone intense scrutiny as part of efforts to understand high-temperature superconductivity. We explore the evolution of the magnetic correlations along the nodal direction of the Brillouin zone in La2−xSrxCuO4, spanning the doping phase diagram from the antiferromagnetic Mott insulator at x=0 to the metallic phase at x=0.26. Magnetic excitations along this direction are found to be systematically softened and broadened with doping, at a higher rate than the excitations along the antinodal direction. This phenomenology is discussed in terms of the nature of the magnetism in the doped cuprates. Survival of the high-energy magnetic excitations, even in the overdoped regime, indicates that these excitations are marginal to pairing, while the influence of the low-energy excitations remains ambiguous.

The magnetic correlations within the cuprates have undergone intense scrutiny as part of efforts to understand high temperature superconductivity. We explore the evolution of the magnetic correlations along the nodal direction of the Brillouin zone in La2-xSrxCuO4, spanning the doping phase diagram from the anti-ferromagnetic Mott insulator at x = 0 to the metallic phase at x = 0.26. Magnetic excitations along this direction are found to be systematically softened and broadened with doping, at a higher rate than the excitations along the anti-nodal direction. This phenomenology is discussed in terms of the nature of the magnetism in the doped cuprates. Survival of the high energy magnetic excitations, even in the overdoped regime, indicates that these excitations are marginal to pairing, while the influence of the low energy excitations remains ambiguous., 8 pages, 6 figures

The so called Heat-shock proteins (Hsp) are the product of different genes induced by a sudden and/or short-lasting temperature elevation. However, the term Hsp is generally used with great flexibility to indicate proteins induced also by other stressors besides heat shock. Many Hsp are also chaperones since they assist nascent polypeptides to fold correctly. Other canonical functions of chaperones include, in addition to protein folding, assisting protein refolding and translocation through membranes, ushering proteins damaged beyond repair to degradation, and dissolution of protein aggregates. Hsp play a key role in various human chronic diseases such as cancer, neurodegenerative diseases, cardiovascular diseases, diabetes and in acute injury (i.e. trauma). Furthermore, Hsps may be used as possible circulating biomarkers helpig the clinicians for diagnosis, prognosis and treatment. In the present review we focus our attention on the possible role and different clinical significance of two important heat shock proteins (i.e. heme oxygenase-1 and Hsp70) in traumatic injury.

By means of resonant inelastic x-ray scattering at the Cu L$_3$ edge, we measured the spin wave dispersion along $\langle$100$\rangle$ and $\langle$110$\rangle$ in the undoped cuprate Ca$_2$CuO$_2$Cl$_2$. The data yields a reliable estimate of the superexchange parameter $J$ = 135 $\pm$ 4 meV using a classical spin-1/2 2D Heisenberg model with nearest-neighbor interactions and including quantum fluctuations. Including further exchange interactions increases the estimate to $J$ = 141 meV. The 40 meV dispersion between the magnetic Brillouin zone boundary points (1/2,\,0) and (1/4,\,1/4) indicates that next-nearest neighbor interactions in this compound are intermediate between the values found in La$_{2}$CuO$_4$ and Sr$_2$CuO$_2$Cl$_2$. Owing to the low-$Z$ elements composing Ca$_2$CuO$_2$Cl$_2$, the present results may enable a reliable comparison with the predictions of quantum many-body calculations, which would improve our understanding of the role of magnetic excitations and of electronic correlations in cuprates., 8 pages, 6 figures

Objectives: To assess the performance of the Pediatric Index of Mortality (PIM) 2 score in Italian pediatric intensive care units (PICUs). Design: Prospective, observational, multicenter, 1-year study. Setting: Eighteen medical-surgical PICUs. Patients: Consecutive patients (3266) aged 0-16 years admitted between 1 March 2004 and 28 February 2005. Interventions: None. Measurements and main results: To assess the performance of the PIM2 score, discrimination and calibration measures were applied to all children admitted to the 18 PICUs, in the entire population and in different groups divided for deciles of risk, age and admission diagnosis. There was good discrimination, with an area under the receiver operating characteristic (ROC) curve of 0.89 (95% CI 0.86-0.91) and good calibration of the scoring system [non-significant differences between observed and predicted deaths when the population was stratified according to deciles of risk (chi(2) 9.86; 8 df, p = 0.26) for the whole population]. Conclusions: The PIM2 score performed well in this sample of the Italian pediatric intensive care population. It may need to be reassessed in the injury and postoperative groups in larger studies.

Contemporary surgical options to remove the thymus gland include median sternotomy with extended resection or minimally invasive techniques. Transcervical thymectomy has been criticized as potentially giving a "lesser" thymectomy. We describe the trans cervical approach with telescope enhancement using a standard VATS camera. This report describes the method emphasising the excellent visualization, and discuss the pro and cons over the classic trans-cervical approach or thymectomies performed by VATS or sternotomy.

International audience; In order to elucidate the origin of the interplay between charge density wave (CDW) and superconductivity in 1T-TaS2, we have synthesized powder samples of pure and C-intercalated 1TCxTaS2 by means of a multi-anvil high-pressure synthesis method. We have found that single-phase samples are obtained in the 2-6 GPa range at 400 °C and for x=0-0.3. The structural, magnetic and transport properties of all samples have been investigated by means of neutron and x-ray diffraction, dc magnetization and dc electrical resistivity. For all x values including x=0, the data show that the CDW phase is suppressed concomitant to an abrupt onset of superconductivity, with Tc=3.2 K for x=0. The Tc value turns out to be weakly dependent on x, with a maximum Tc=3.8 K for x=0.2. This onset is accompanied by a crossover of magnetic behavior from paramagnetic Pauli-like to paramagnetic Curie-Weiss-like with effective moment μ ≈ 1.2 μB/Ta, which suggests that a ionic picture is suitable for the superconducting phase, but not for the CDW phase. The analysis of the dependence of the a and c lattice parameters upon x as well as upon the synthesis conditions shows that the onset of superconductivity is mainly ascribed to unusual changes of the unit cell induced by the high-pressure synthesis. Specifically, the ex-situ lattice parameters exhibit a significantly larger c-axis parameter and a shrinking of the a-axis parameter stabilized by the high-pressure synthesis route. We argue that the above suppression of the CDW phase is induced by a broadening of the relevant 5d(t2g) band which stabilizes the metallic and superconducting phases. This scenario suggests that the strength of the electronic correlations are the main control parameter of the CDWsuperconductivity competition in 1T-TaS2.

International audience; We report the first measurement of the Cu-O bond stretching phonon dispersion in optimally doped Bi2 Sr1:6 La0:4 Cu2 O6

International audience; In order to account for the large drop of superconducting critical temperature, T, and for the dramatic increase in residual resistivity, rho(0), previously reported in CaC6 at P-cr approximate to 9 GPa, we studied the room-temperature crystal structure of bulk CaC6 samples as a function of pressure up to 13 GPa by means of synchrotron x-ray diffraction in diamond anvil cells. At P-cr, we found no change of the trigonal R m space group symmetry, but a large increase in isothermal compressibility, kappa, from -0.0082 GPa(-1) to -0.0215 GPa(-1), accompanied by a large broadening of Bragg peaks. With both effects being reversible, it follows that superconductivity in CaC6 is maximized at the verge of a peculiar order-disorder phase transition concomitant to a large lattice softening. Space group symmetry considerations supported by ab initio calculations of the relaxed structure within the density functional theory lead us to conclude that the disordered phase is presumably characterized by a random off-centering of the Ca atoms in the ab plane with respect to the C honeycomb layers.

Near infrared spectroscopy (NIRS) is a non invasive optical technique to assess the monitoring of oxygenation and cerebral hemodynamics. Aim of our study was to value cerebral hemodynamics during major surgery to reduce the period of possible modifications of cerebral oxygenation.Twenty-five newborns which underwent surgical intervention (8 diaphragmatic hernia, 8 esophageal atresia, 1 neck lymphangioma, 8 intestinal malformation) were studied during surgery by means of NIRS (NIRO 300), using an electrode applied to the scalp in the frontoparietal region. We monitored the Tissue Oxygenation Index (TOI) as well as the changes in concentration of total haemoglobin (tHb), oxygenated haemoglobin (O2Hb) and deoxygenated haemoglobin (HHb). The changes have been expressed as difference from the basal value recorded at the beginning of surgery.During the surgical intervention O2Hb, tHb and TOI decreased (DeltaO2Hb=-11.4+/-6.5 microM; P0.001; DeltatHb=- 7.54+/-4.3 microM, P0.05; microTOI=-12.5+/-5.5%, P0.001), and HHb increased (DeltaHHb=+4.80+/-2.30 microM, P0.001); the greatest changes occurred when the viscera were positioned into the abdomen (in diaphragmatic hernia and intestinal malformation).The present study suggests that NIRS, during major surgery, is able to monitor oxygenation and cerebral hemodynamics thus allowing a real time evaluation of some intraoperative procedure aftereffects that, if timely modified, could reduce cerebral hypoxia risks.

In order to study the possibility of enhancing the electron-phonon coupling in cuprates by soft transverse acoustic TA modes, using high-resolution (dE=1.3 meV) inelastic x-ray scattering, we measured the inplane TA mode at low qd0.1 along the a* axis on optimally doped untwinned YBa2Cu3O(7-delta) single crystals. We find that the dispersion is linear with no softening down to q=0.02 and unchanged upon cooling from 300 to 98 K. The sound velocity is found to be 2700±70 m/s, in agreement with ultrasound data. Thus, no bending instability exists in the CuO2 layers and we conclude that larger and Tc may be possible in cuprates by inducing this instability.

This paper describes a case of drug-induced hepatitis that onset in a patient who was hospitalised in our department after administration of calcium heparin. The rarity of the case was shown not only by the very short time elapsed between cause (drug administration) and effect (bio-humoral changes detected), but also by the histology results of the liver biopsy. This latter confirmed that mechanisms of idiosyncrasy, which may cause liver cell necrosis, can occur after administration of any drug.

Neutron-diffraction data collected under vacuum at 680 and 695 K have been compared with elastic energy dissipation and dynamic Young’s modulus measurements in YBa2Cu3O6+x. The orthorhombic to tetragonal phase transition has been observed in isothermal conditions. The data suggest that a phonon softening occurs at the oxygen disordering, which, in these experimental conditions, precedes the phase transition. The elastic energy dissipation presents a peak above room temperature. Its origin and behavior are discussed in terms of an oxygen atom repopulation model, with activation energy depending on the orthorhombic strain and oxygen ordering in the basal plane.

We measure phonon dispersion and linewidth in a single crystal of MgB_2 along the Gamma-A, Gamma-M and A-L directions using inelastic X-Ray scattering. We use Density Functional Theory to compute the effect of both electron-phonon coupling and anharmonicity on the linewidth, obtaining excellent agreement with experiment. Anomalous broadening of the E_2g phonon mode is found all along Gamma-A. The dominant contribution to the linewidth is always the electron-phonon coupling., Comment: 4 pages, 3 figures