[Spontaneous coronary artery dissection in young male patient with STEMI: Unsuccessful fibrinolysis]. / Dissection coronaire spontanée dans le SCA ST+ chez un homme jeune : échec de fibrinolyse.

Spontaneous coronary artery disease (SCAD) is a particular form of acute coronary syndrome affecting preferentially female patient with few or without traditional cardiovascular risk factors. Male patient is exceptionally concerned by SCAD. We report a case of a young male patient presenting with anterolateral STEMI in relation with SCAD of Left main and left anterior descending artery (LAD). He was initially managed by fibrinolysis, which is then complicated by cardiogenic choc. Coronary angiogram covered by intra-aortic balloon pump (IABP) showed an acute double occlusion of proximal LAD and the ostium of the left circumflex artery (LCX). After thrombus aspirations, the angiographic pattern recalled a SCAD, which is confirmed by OCT (Optical Coherence Tomography). The latter highlighted the intimal flap with true and false lumen involving both Left main and proximal LAD with huge thrombus burden. PCI was then performed successfully with implantation of 3 DES (Drug Eluting Stent). But given the cardiogenic shock persistence despite Dobutamin infusion and IABP, ECMO (Extracorporeal membrane oxygenation) was indicated. Unfortunately, the patient died of haemorrhage during ECMO implantation.

COMET: a new end-station at SOLEIL for coherent magnetic scattering in transmission.

A new instrument named COMET for COherent Magnetic scattering Experiments in Transmission using polarized soft X-rays has been designed and built. This high-vacuum setup is placed at the intermediate focal point of the elastic branch of the SEXTANTS beamline at Synchrotron SOLEIL. The main application is in solid state physics, the instrument being optimized for studying material properties using coherent scattering of soft X-rays with an emphasis on imaging, with chemical selectivity, the magnetic domains of artificially nano-structured materials. The instrument's principal features are presented and illustrated through recently performed experiments.

Fragmentation of pure and hydrated clusters of 5Br-uracil by low energy carbon ions: observation of hydrated fragments.

The fragmentation of the isolated 5-bromouracil (5BrU) molecule and pure and nano-hydrated 5BrU clusters induced by low energy 12C4+ ions has been studied. A comparison indicates that the environment, on the one hand, protects the system against the complete break-up into small fragments, but, on the other hand, triggers 'new' pathways for fragmentation, for example the loss of the OH group. The most striking result is the observation of several series of hydrated fragments in the hydrated cluster case, with water molecules bound to hydrophilic sites of 5BrU. This highlights the strong interaction between 5BrU and water molecules and the blocking of specific fragmentation pathways, such as the loss of the BrC2H group for example.

Determination of Energy-Transfer Distributions in Ionizing Ion-Molecule Collisions.

The ionization and fragmentation of the nucleoside thymidine in the gas phase has been investigated by combining ion collision with state-selected photoionization experiments and quantum chemistry calculations. The comparison between the mass spectra measured in both types of experiments allows us to accurately determine the distribution of the energy deposited in the ionized molecule as a result of the collision. The relation of two experimental techniques and theory shows a strong correlation between the excited states of the ionized molecule with the computed dissociation pathways, as well as with charge localization or delocalization.

Site- and state-selected photofragmentation of 2Br-pyrimidine.

The fragmentation of the 2Br-pyrimidine molecule following direct valence photoionization or inner shell excitation has been studied by electron-ion coincidence experiments. 2Br-pyrimidine has been chosen as a model for the class of pyrimidinic building blocks of three nucleic acids and several radiosensitizers. It is known that the site- and state-localization of energy deposition, typical of inner shell excitation, results in the enhancement of the total ion yield as well as in changes in the relative intensity of the different fragmentation channels. Here we address the question of the origin of this selective fragmentation by using electron-ion coincidence techniques. The results show that the fragmentation is strongly selective in the final singly charged ion state, independently of the process that leads to the population of that state, and the dominant fragmentation patterns correlate with the nearest appearance potential.

Schmallenberg virus: experimental infection in goats and bucks.

BACKGROUND: Schmallenberg virus (SBV) is an emerging Orthobunyavirus of ruminant livestock species currently circulating in Europe. SBV causes a subclinical or mild disease in adult animals but vertical transmission to pregnant dams may lead to severe malformations in the offspring. Data on the onset of clinical signs, viremia and seroconversion in experimentally infected adult animals are available for cattle and sheep but are still lacking for goats. For a better understanding of the pathogenesis of SBV infection in adult ruminants, we carried out experimental infections in adult goats. Our specific objectives were: (i) to record clinical signs, viremia and seroconversion; (ii) to monitor viral excretion in the semen of infected bucks; (iii) to determine in which tissues SBV replication took place and virus-induced lesions developed. RESULTS: Four goats and two bucks were inoculated with SBV. Virus inoculation was followed by a short viremic phase lasting 3 to 4 days and a seroconversion occurring between days 7 and 14 pi in all animals. The inoculated goats did not display any clinical signs, gross lesions or histological lesions. Viral genomic RNA was found in one ovary but could not be detected in other organs. SBV RNA was not found in the semen samples collected from two inoculated bucks. CONCLUSIONS: In the four goats and two bucks, the kinetics of viremia and seroconversion appeared similar to those previously described for sheep and cattle. Our limited set of data provides no evidence of viral excretion in buck semen.

Formation of H2 from internally heated polycyclic aromatic hydrocarbons: excitation energy dependence.

We have investigated the effectiveness of molecular hydrogen (H2) formation from Polycyclic Aromatic Hydrocarbons (PAHs) which are internally heated by collisions with keV ions. The present and earlier experimental results are analyzed in view of molecular structure calculations and a simple collision model. We estimate that H2 formation becomes important for internal PAH temperatures exceeding about 2200 K, regardless of the PAH size and the excitation agent. This suggests that keV ions may effectively induce such reactions, while they are unlikely due to, e.g., absorption of single photons with energies below the Lyman limit. The present analysis also suggests that H2 emission is correlated with multi-fragmentation processes, which means that the [PAH-2H](+) peak intensities in the mass spectra may not be used for estimating H2-formation rates.

Magnetization and microstructure dynamics in Fe/MnAs/GaAs(001): Fe magnetization reversal by a femtosecond laser pulse.

Thin film magnetization reversal without applying external fields is an attractive perspective for applications in sensors and devices. One way to accomplish it is by fine-tuning the microstructure of a magnetic substrate via temperature control, as in the case of a thin Fe layer deposited on a MnAs/GaAs(001) template. This work reports a time-resolved resonant scattering study exploring the magnetic and structural properties of the Fe/MnAs system, using a 100 fs optical laser pulse to trigger local temperature variations and a 100 fs x-ray free-electron laser pulse to probe the induced magnetic and structural dynamics. The experiment provides direct evidence that a single optical laser pulse can reverse the Fe magnetization locally. It reveals that the time scale of the magnetization reversal is slower than that of the MnAs structural transformations triggered by the optical pulse, which take place after a few picoseconds already.

Absolute fragmentation cross sections in atom-molecule collisions: scaling laws for non-statistical fragmentation of polycyclic aromatic hydrocarbon molecules.

We present scaling laws for absolute cross sections for non-statistical fragmentation in collisions between Polycyclic Aromatic Hydrocarbons (PAH/PAH(+)) and hydrogen or helium atoms with kinetic energies ranging from 50 eV to 10 keV. Further, we calculate the total fragmentation cross sections (including statistical fragmentation) for 110 eV PAH/PAH(+) + He collisions, and show that they compare well with experimental results. We demonstrate that non-statistical fragmentation becomes dominant for large PAHs and that it yields highly reactive fragments forming strong covalent bonds with atoms (H and N) and molecules (C6H5). Thus nonstatistical fragmentation may be an effective initial step in the formation of, e.g., Polycyclic Aromatic Nitrogen Heterocycles (PANHs). This relates to recent discussions on the evolution of PAHNs in space and the reactivities of defect graphene structures.

[Vascular complications at the femoral access: impact of the percutaneous closure device Perclose]. / Complications vasculaires de l'abord artériel fémoral: impact du système de fermeture percutanée Perclose.

INTRODUCTION: Vascular complications at the femoral access site is an important factor of morbidity. The aims of this study were to evaluate the efficacy and safety of the percutaneous closure device (Perclose) during interventional cardiology procedures. PATIENTS AND METHODS: All patients with percutaneous closure of the femoral access site by the Perclose system in 2010 were included. We evaluated the indications of the procedures, the success rate of implantation and the bleeding complications according to antithrombotic therapy used. RESULTS: Three hundred and seventy five patients underwent a percutaneous closure by the Perclose system. Acute coronary syndromes with or without elevation of ST segment were the main indications of procedures (74.9%). The success rate of percutaneous closure of the femoral access site was 97.3%. The rate of minor, moderate, and severe bleeding of the entire cohort according to the GUSTO classification was respectively 4.2%, 0.5% and 1%. Bleeding complications were similar in both groups of patients (2.1% vs 7% P=0.122). In case of unsuccessful deployment of femoral closure devices, the risk of bleeding complications range from 4.3% to 60% (P=0.0000036). CONCLUSION: The use of the Perclose system is associated with a low rate of severe bleeding at the femoral access site. However, the failures of percutaneous closure increase the risk of bleeding complications.

[Very late bare-metal stent thrombosis 10 years after the implantation: a case report]. / Thrombose très tardive d'un stent nu dix ans après son implantation : à propos d'une observation.

Very late thrombosis occurring after bare-metal stent (BMS) implantation is a rare complication. It differs from very late thrombosis of drug-eluting stents in terms of both frequency and pathophysiological mechanism. We report a case of very late stent thrombosis of a bare-metal stent 10 years after his implantation for treatment of a myocardial infarction. The patient had a new acute coronary syndrome without persistent ST-segment elevation related to bare-metal stent thrombosis. He was treated by thrombo-aspiration and implantation of a new bare-metal stent.

Ultrafast optical demagnetization manipulates nanoscale spin structure in domain walls.

During ultrafast demagnetization of a magnetically ordered solid, angular momentum has to be transferred between the spins, electrons, and phonons in the system on femto- and picosecond timescales. Although the intrinsic spin-transfer mechanisms are intensely debated, additional extrinsic mechanisms arising due to nanoscale heterogeneity have only recently entered the discussion. Here we use femtosecond X-ray pulses from a free-electron laser to study thin film samples with magnetic domain patterns. We observe an infrared-pump-induced change of the spin structure within the domain walls on the sub-picosecond timescale. This domain-topography-dependent contribution connects the intrinsic demagnetization process in each domain with spin-transport processes across the domain walls, demonstrating the importance of spin-dependent electron transport between differently magnetized regions as an ultrafast demagnetization channel. This pathway exists independent from structural inhomogeneities such as chemical interfaces, and gives rise to an ultrafast spatially varying response to optical pump pulses.

[Use of drug-eluting stents: impact of French recommendations on the rate of clinical restenosis at 2 years]. / Utilisation des stents actifs : impact des recommandations françaises sur le taux de resténose clinique à deux ans.

AIMS: The drug-eluting stents (DES) reduce restenosis rate compared to bare metal stents. The clinical efficacy is greater in some subgroups of patients at high risk of restenosis. The aim of this study is to evaluate the use of drug-eluting stent based on the recommendations of the French Society of Cardiology and its impact on the restenosis rate at 2 years. METHODS: We included all patients who had coronary angioplasty with stenting in 2008. We evaluated the percentage of drug-eluting stent, the proportion of patients for which the French recommendations have been followed, and the rate of clinical restenosis at 2 years. RESULTS: Four hundred and seventy-nine angioplasties were performed in 2008. The percentage of drug-eluting stents was 21.8%. Acute coronary syndrome with or without elevation of the ST segment were the main indications of angioplasty (67.9%). For the 115 drug-eluting stents implanted in 2008, French recommendations were followed in 93% of cases (107 stents). For 89 patients who received DES, these recommendations were followed in 91% of cases (81 patients). The clinical restenosis rate at 2 years evaluated in 89% of patients was 5.6%. The rate of in-stent restenosis in bare metal and drug-eluting stents were 5.9 and 3.7%. CONCLUSION: The use of DES in our center is characterized by a small rate and a good compliance of the recommendations of the French Society of Cardiology. This strategy is associated with a low rate of restenosis at 2 years of follow-up.

Probing the transition in bulk Ce under pressure: a direct investigation by resonant inelastic X-ray scattering.

We report on the most complete investigation to date of the -electron properties at the transition in elemental Ce by resonant inelastic x-ray scattering (RIXS). The Ce 2p3d-RIXS spectra were measured directly in the bulk material as a function of pressure through the transition. The spectra were simulated within the Anderson impurity model. The occupation number n(f) and f double occupancy were derived from the calculations in both gamma and alpha phases in the ground state. We find that the electronic structure changes result mainly from band formation of 4f electrons which concurs with reduced electron correlation and increased Kondo screening at high pressure.

f-State occupancy at the gamma-alpha phase transition of Ce-Th and Ce-Sc alloys.

Resonant inelastic x-ray scattering spectra were measured for a series of Ce solid solutions (Ce-Th and Ce-Sc) across the gamma-alpha phase transition. They reveal a well-defined feature associated with the 4f2 configuration when the incident energy is tuned to the Ce L3 preedge region. This component is normally hidden in x-ray absorption spectra because of lifetime broadening. The f1/f2 ratio estimated by resonant inelastic x-ray scattering presents a sharp drop across the gamma-alpha transition and hysteresis as a function of temperature that closely resemble the magnetization loop. These measurements confirm recent dynamical mean-field theory calculations that unexpectedly predict significant double occupancy of f orbitals in the ground state.

SB7: the new bending-magnet double-headed dragon beamline at SuperACO.

A new beamline is now operational at LURE on bending-magnet 7 of the SuperACO storage ring in Orsay. The monochromator is of the ;dragon' type, designed to work in the energy range 150-1500 eV, and is equipped with a double vertical focusing mirror in order to allow for fast switching of light polarization. In this paper the results of photoion-yield experiments performed on N(2), Ar and Ne gases are presented. The observed resonance structures enable us to determine the available energy resolution: a resolving power higher than 8500 is obtained at the Ar 2p, N 1s and Ne K-edges when using all the optical elements at full aperture. The total flux as a function of the measured photon energy resolution and the characterization of the double-head behaviour in delivering circularly polarized light are reported.

The gas-phase photoemission beamline at Elettra.

This paper reports the present stage of commissioning of the gas-phase photoemission beamline at Elettra, Trieste. The beamline is designed for atomic and molecular science experiments with high-resolution and high-flux synchrotron radiation. It consists of an undulator source, variable-angle spherical-grating monochromator and two experimental stations. The design value of the energy range is 20 to 800 eV with a specified resolving power of over 10000. The procedure adopted for calibration of this type of monochromator is discussed. At present a resolving power up to 20000 and a range up to 900 eV have been measured. Absorption spectra taken at the argon L(II,III)-edge and at the nitrogen, oxygen and neon K-edges are as sharp as, or sharper than, any reported in the literature. The instrumental broadening is well below the natural line-width making it difficult to quantify the resolution; this problem is discussed.

Quantification of experimental Salmonella enteritidis carrier state in B13 leghorn chicks.

Quantification of the carrier state of Salmonella enteritidis in chicks (i.e., persistent asymptomatic association of S. enteritidis with the host), should provide an optimized means for further investigations into this problem. We therefore developed an experimental carrier state model by oral inoculation of low doses (10(2)-10(4)) of S. enteritidis in B13 chicks at different ages. Liver, spleen, and ceca colonizations by the challenge strains were measured weekly by enumeration of S. enteritidis colony-forming units (CFU) for 7-12 weeks. High mortality rates, incompatible with the carrier state, were observed in chicks inoculated with 10(2) organisms of either a parental strain of S. enteritidis (5556) or a mutant resistant to streptomycin (Smr) and nalidixic acid (Nalr) (strain 1009) at 1 day old. Both strains colonized organs similarly, allowing us to use subsequently the SmrNalr mutant strain. The selected low doses of S. enteritidis induced no deaths in chicks inoculated at 1 or 3 weeks of age. However, inoculation of 3-week-old chicks did not induce a satisfactory carrier state; organ colonization by S. enteritidis was weak and transient, even after inoculation of 10(8) SE. In contrast, some birds infected at 1 week of age presented the challenge strain in the liver and spleen for 3 weeks after inoculation and in the ceca for 12 weeks postchallenge. Most of these birds were colonized by S. enteritidis in the liver and in the ceca for 3 weeks and 10 weeks, respectively, following inoculation. Generally, CFU levels were highest during the first week(s) after inoculation and then decreased progressively. Levels of S. enteritidis were lower in the liver and spleen than in the ceca. Oral inoculation of 1-week-old birds with 5 x 10(4) S. enteritidis provided the required model, allowing quantification of the carrier state of S. enteritidis in chicks.