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Due to their high cost of acquisition and operation, there are still a limited number of high-yield, high-flux neutron source facilities worldwide. In this context, laser-driven neutron sources offer a promising, cheaper alternative to those based on large-scale accelerators, with, in addition, the potential of generating compact neutron beams of high brightness and ultra-short duration. In particular, the predicted capability of next-generation petawatt (PW)-class lasers to accelerate protons beyond the 100 MeV range should unlock efficient neutron generation through spallation reactions. In this paper, this scenario is investigated numerically through particle-in-cell and Monte Carlo simulations, modeling, respectively, the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary heavy-ion targets. Laser parameters relevant to the 1 PW LMJ-PETAL and 1-10 PW Apollon systems are considered. Under such conditions, neutron fluxes exceeding $10^{23}\,\rm n\,cm^{-2}\,s^{-1}$ are predicted, opening up attractive fundamental and applicative prospects., Comment: 16 pages, 13 figures

Objectives To analyze the impact of bilateral cochlear implantation (CI) on perceptual and linguistic development in hearing-impaired children with congenital Cytomegalovirus (CMV) infection. Patients and method A retrospective study was performed for the period 1991-2016 in a pediatric CI reference center. Closed Set Word (CSW) recognition scores, Categories of Auditory Performance (CAP) and linguistic level on the MT Lenormand scale (MTL) were compared between bilateral (Bi) and unilateral (Uni) groups 12, 24 and 36 months after first CI (CI-1). Results 84 patients with congenital CMV infection who underwent CI were included, in 2 groups: sequential or simultaneous bilateral CI (Bi) (N = 20), and unilateral CI (Uni) (N = 64). Twelve, 24 and 36 months after CI-1, CSW scores were 35.56%, 64.52% and 82.93% in Uni and 60.3%, 85% (P = 0.0084*), and 100% (P = 0.00085*) in Bi. CAP scores 12, 24 and 36 months after CI-1 were 2.57, 3.85 and 4.3 in Uni and 3.91 (P = 0.0068*), 5.00 (p = 0.029*) and 5.50 (P = 0.051*) in Bi. MTL linguistic level scores at 12, 24 and 36 months were 0.72, 1.25 and 1.65 in Uni, and 1.72, 3 (P = 0.033) and 3.11 (P = 0.045) in Bi. These significantly better scores in Bi at 24 and 36 months after CI-1 were also found on analysis of subgroups with no associated neurologic disorder (P = 0.046* and P = 0.032*), no associated psychiatric pathology (P = 0.0055* and P = 0.0073*), and no other associated disorder (P = 0.0018* and P = 0.035*), and for all subgroups together (P = 0.0036 and P = 0.037). Conclusion Bilateral CI is a faster way than unilateral CI for patients with congenital CMV infection to achieve structured fluent oral language. 50% of the series showed cerebral abnormalities on MRI, without difference between groups. This was not in itself predictive of poor progression of oral communication, unless associated with major neurologic disorder. Some children made little or no use of their CI in the medium term.

Resume Objectif Ealuer l’interet de l’implantation cochleaire (IC) bilaterale sur le developpement perceptif et linguistique des enfants sourds atteints de fœtopathie a cytomegalovirus (CMV). Materiel et methodes Etude retrospective, dans un centre de reference d’IC pediatrique entre 1991 et 2016. L’analyse des resultats perceptifs utilisaient la reconnaissance de mots en liste fermee (MLF) et la categorie de performance auditive (CAP), et pour l’expression orale utilisait l’echelle de MT Lenormand (MTL). Les patients de chaque groupe (bilateral, unilateral) ont ete compares a 12, 24 et 36 mois de recul de la premiere implantation (IC1). Resultats Un total de 84 enfants ayant une foetopathie a CMV ont beneficie d’un IC et ont ete inclus. Deux groupes ont ete definis, « IC bilateral, sequentiel ou simultane » (Gbilat ; n = 20), « IC unilateral » (Gunilat ; n = 64). A 12, 24 et 36 mois de recul a l’IC1, les scores de MLF etaient respectivement dans le Gunilat et le Gbilat de : 35,56 %, 64,52 %, 82,93 % et de 60,3 %, 85 % (p = 0,0084), 100 % (p = 0,00085). Les scores du CAP a 12, 24 et 36 de recul de l’IC1, etaient dans le Gunilat de 2,57, 3,85 et 4,3 et dans le Gbilat de 3,91 (p = 0,0068), 5,00 (p = 0,029), et 5,50 (p = 0,051). L’echelle de MTL montrait a 12, 24 et 36 mois de recul a l’IC1, des scores de 0,72, 1,25 et 1,65 dans le Gunilat et de 1,72, 3 (p = 0,033), 3,11 (p = 0,045) dans le Gbilat. Les differences statistiquement significatives constatees a 24 et 36 mois de recul a l’IC1 persistaient dans l’analyse en sous-groupes chez ces memes patients n’ayant ni troubles neurologiques isoles (p = 0,046 et p = 0,032), ni troubles psychiatriques isoles (p = 0,0055 et p = 0,0073), ni troubles associes isoles (p = 0,0018 et p = 0,035) ou confondus (p = 0,0036 et p = 0,037). Conclusion L’IC bilaterale permet aux patients atteints de fœtopathie a CMV d’acquerir plus rapidement un langage oral courant structure qu’avec un IC unilateral. L’atteinte cerebrale etait presente dans les deux groupes en IRM et frequente dans cette population (50 % des cas). Elle n’etait pas un facteur de difference entre les deux groupes en revanche. Les troubles neurologiques majeurs associes etaient un facteur de pronostic defavorable pour une entree dans le langage oral et certains utilisaient peu ou pas leur implant a moyen terme.

We detail results of an experiment performed at the Ligne d'Intégration Laser facility aimed at studying supersonic and diffusive radiation front propagation in low-density SiO2 aerogel (20 and 40 mg/cm3) enclosed in a gold tube, driven by thermal emission from a laser-heated spherical gold cavity. The evolution of the front is studied continuously by measuring its self-emission with a 1D (one-dimensional) time-resolved soft x-ray imager. Measurement is performed along (through a 200- μm-wide observation slit) and at the exit of the tube giving access to the dynamics and the curvature of the front. Experimental results are then compared successfully to results from the 3D (three-dimensional) radiation hydrodynamics code TROLL, which shows that if continuous tracking of the front position is accessible with this experimental scheme, measurement of its maximum radiation temperature is on the contrary affected by radiation closure of the observation slit. 3D simulations also indicate that this effect can even be worsened if one includes pointing errors of the x-ray imager. Radiation temperature along the tube was then inferred by combining results from the imager to a wall shock breakout time measurement using a velocity interferometer system for any reflector and results from a broadband x-ray spectrometer used to determine the temperature at the exit of the tube. A decrease in the radiation temperature along the tube is observed, the decrease being more important for the higher SiO2 aerogel density.

La enfermedad venosa cronica (EVC) es una patologia muy frecuente. La insuficiencia venosa superficial cronica de los miembros inferiores representa la forma mas avanzada. Las varices se definen como venas subcutaneas palpables y dilatadas de un diametro por lo general mayor de 4 mm. El factor hereditario es predominante. Las venas superficiales drenan la sangre procedente de los tejidos supraaponeuroticos y la conducen hacia las venas profundas a traves de dos ejes venosos principales: la vena safena mayor (VSMa) y la vena safena menor (VSMe). El paciente consulta en la mayoria de los casos por trastornos funcionales. La exploracion fisica permite precisar el estadio de la enfermedad y apreciar su importancia y su repercusion. Las complicaciones agudas son la trombosis venosa superficial, la trombosis venosa profunda (TVP) y la ruptura varicosa. Las complicaciones tardias son las pigmentaciones, la atrofia blanca, las hipodermitis, las calcificaciones subcutaneas y las ulceras de la pierna, que son las mas preocupantes. La ecografia Doppler de los miembros inferiores es la exploracion de referencia para el diagnostico, las particularidades anatomicas y hemodinamicas de la insuficiencia venosa superficial y para determinar el tratamiento mas apropiado. El tratamiento de la insuficiencia venosa cronica se dirige a disminuir los sintomas y a prevenir las complicaciones. La compresion es un tratamiento obligatorio. Los venotonicos estan indicados en las manifestaciones funcionales de la insuficiencia venosa cronica no grave. La aparicion de los tratamientos endovenosos (ecoescleroterapia con espuma, laser, radiofrecuencia) ha provocado una reduccion evidente de las indicaciones quirurgicas en el tratamiento de la insuficiencia venosa superficial.

International audience; We detail results of an experiment performed at the Laser Mégajoule (LMJ) facilityaimed at studying transition from supersonic radiation front to shock front in a lowdensity CHOBr foam enclosed in a plastic tube driven by thermal emission producedin a laser heated spherical gold cavity. Time resolved 2D hard x-ray radiographyimaging using a Sc source (photon energy at ~ 4.3 keV) is employed to measure thedensity perturbation front position, absorption, curvature and shocked materialcompression (defined as the compressed foam density normalized to its nominal value)from the supersonic to the subsonic regimes of propagation. Between these two regimeswhere compression goes from 1 (limited hydrodynamics) to 4 (strong shock formed), aquick increase of the foam compression is observed at the transition time tHS =6.75±0.75 ns, corresponding to the transient transonic regime (HS means“hydrodynamically separated” and refers to the instant when the shock and the radiationfront physically separate). This time is associated to a foam compression ratio of ~2and a Mach number of the slowing down front below M < 2. Experimental results aresuccessfully compared to 3D hydrodynamics simulations; comparisons never presentedfor that regime in past similar studies to our knowledge. Simulations show that thetransition time tHS is sensitive to the radiation closure of the tube entrance. This closure, which occurs in 3D, affects the amount of x-ray energy coupled from the laser heatedcavity to the CHOBr foam, and consequently the transient transonic regime dynamics.

Background Transcranial laser stimulation is a novel method of noninvasive brain stimulation found safe and effective for improving prefrontal cortex neurocognitive functions in healthy young adults. This method is different from electric and magnetic stimulation because it causes the photonic oxidation of cytochrome-c-oxidase, the rate-limiting enzyme for oxygen consumption and the major intracellular acceptor of photons from near-infrared light. This photobiomodulation effect promotes mitochondrial respiration, cerebrovascular oxygenation and neurocognitive function. Pilot studies suggest that transcranial photobiomodulation may also induce beneficial effects in aging individuals. Objectives Randomized, sham-controlled study to test photobiomodulation effects caused by laser stimulation on cytochrome-c-oxidase oxidation and hemoglobin oxygenation in the prefrontal cortex of 68 healthy younger and older adults, ages 18–85. Methods Broadband near-infrared spectroscopy was used for the noninvasive quantification of bilateral cortical changes in oxidized cytochrome-c-oxidase and hemoglobin oxygenation before, during and after 1064-nm wavelength laser (IR-A laser, area: 13.6 cm2, power density: 250 mW/cm2) or sham stimulation of the right anterior prefrontal cortex (Brodmann Area 10). Results As compared to sham control, there was a significant laser-induced increase in oxidized cytochrome-c-oxidase during laser stimulation, followed by a significant post-stimulation increase in oxygenated hemoglobin and a decrease in deoxygenated hemoglobin. Furthermore, there was a greater laser-induced effect on cytochrome-c-oxidase with increasing age, while laser-induced effects on cerebral hemodynamics decreased with increasing age. No adverse laser effects were found. Conclusion The findings support the use of transcranial photobiomodulation for cerebral oxygenation and alleviation of age-related decline in mitochondrial respiration. They justify further research on its therapeutic potential in neurologic and psychiatric diseases.

Resume Introduction L’occlusion de la veine femorale commune (OVFC) d’origine iatrogene, secondaire a la pose de catheters femoraux ou a des interventions au niveau du Scarpa, est une cause rare mais tres symptomatique d’insuffisance veineuse chronique. Ces patients, insuffisamment soulages par la compression veineuse elastique, sont des candidats pertinents a une procedure endovasculaire de recanalisation veineuse. Methodes Nous rapportons une serie de trois cas d’OVFC developpee a la suite d’interventions au niveau du Scarpa, leur procedure de recanalisation, le controle par echo-Doppler et le suivi a court terme. Resultats Dans chacun des cas, la recanalisation endovasculaire a necessite du materiel rigide (guide rigide ou aiguille de Colapinto) afin de traverser les adherences fibreuses avant de realiser une angioplastie avec pose de stent. Ces procedures complexes ont permis une recanalisation efficace immediate, sans complication majeure. Le controle par echo-Doppler confirmait la permeabilite de la veine femorale commune. Lors de la consultation de controle, les patients ont constate une amelioration rapide et significative de leurs symptomes. Conclusion Chez les patients souffrant d’insuffisance veineuse chronique severe par OVFC d’origine iatrogene, une recanalisation endovasculaire peut etre proposee. Bien qu’il s’agisse de procedures complexes en raison de la fibrose etendue au niveau du Scarpa et necessitant du materiel specialise, aucune complication majeure n’a ete constatee.

Implosion experiments of an inertial confinement fusion (ICF) target on the laser megajoule (LMJ) and the National Ignition Facility require, for certain designs, a precise timing coalescence of fo...

International audience; Two alumina coatings are developed to protect tool surface in hot forging: pure γ-alumina matrix loaded with α-alumina particles and pure γ-alumina matrix loaded with h-BN particles. The coatings are deposited on stainless tools by using a sol-gel procedure. Adherent coatings are obtained with an average thickness ranging from 200 to 300 nm. The coatings are tested according to the conditions of contact encountered in hot forging processes: coated tools slide against the surface of hot specimens where they generate a plastic strain. The design of experiment involves specimens heated to 1100 °C, lubricated and unlubricated contact, small and large specimen plastic strain, uncoated and sol-gel coated tools. Tests results are the Coulomb's coefficient of friction, SEM-EDS and roughness measurement of the tool surfaces after a sliding length of 40 mm.Results show that the tested sol-gel coatings remain firmly bonded to the tool surface. Compared to uncoated tools, alumina sol-gel coatings limit the amount of material transfer from specimen surface to tool surface. Loading the alumina sol-gel coating with h-BN particles significantly improves its friction behaviour: the friction coefficient is lower and sticking phenomena are reduced.

Background The cornerstone of therapy in thromboangiitis obliterans (TAO) is complete abstinence from tobacco. In addition to discontinuation of cigarette smoking, very few pharmacological and surgical options of controversial efficacy are available to date. TAO is associated with a high amputation rate because of tobacco continuation, medical therapy failure, and desert foot with no revascularisation option. Endovascular or bypass revascularisation patency and efficacy are poorly described in the literature. Objectives To describe the results of the French National Reference Centre on TAO on revascularisation modalities, their patency and efficacy. Methods Among the 198 patients followed in our centre, we retrieved data from 19 patients for who a revascularisation procedure has been attempted. Patency was assessed on angioCT scan and Duplex ultrasounds performed during follow-up. Efficacy was assessed according to clinicians in charge of the patient, and if an amputation had been performed or not despite a primary successful procedure. Results In this cohort of 19 patients, 16 were male (84%), all were tobacco active users, and 21% cannabis users. Median follow-up was 19.9 months [11.0–36.9]. Iloprost infusion had been tested for 84.2% of the patients before revascularisation, and 63.2% had a dihydropiridine, 73.3% a statin and 100% at least aspirin. Endovascular procedure was exclusive for 14 patients, and bypass surgery for 1 patient. Four patients had combined procedures. Globally, 44 procedures including 7 bypasses (15.9%) and 37 endovascular surgeries (84.1%), due to multiple procedures for some patients. Primary patency of endovascular procedures was 89.4% and their patency duration was 221±173 days. For bypass surgery, the patency duration was higher 827±408 days (p=0.273). Looking at the territory, aorto-iliac revascularizations gave better results on long term 1830 days followed by upper limb 751±402 days, femoro-popliteal procedures 347±196 days and finally infra-popliteal ones with 178±134 days. Stability or improvement was observed after 52.3% of the revascularizations. Among the failures, 21.2% were associated with a minor amputation, and 11.3% with a major amputation. No predicting factors of failure could have been determined. Conclusions We report the largest series of revascuarization in TAO. As expected, proximal artery revascularisation of lower limbs were associated with a higher and a longer patency rate than femoro-popliteal procedures and even more than infra-popliteal revascularisations. Suprinsingly, upper limb revascularisation had a better outcome than for lower limbs. Efficacy of revascularizations are difficult to assess because such procedures are often proposed as a salvage option. However, it is worth to note that more than 50% of the patients had a benefit from the revascularisation. Disclosure of Interest T. Mirault Grant/research support from: GENZYME (2010) M. Delahaye: None declared, A. Galloula: None declared, M. Guillet: None declared, S. Zarka: None declared, M.-C. Courtois: None declared, M. Sapoval: None declared, G. Goudot: None declared, E. Messas: None declared

Common femoral vein occlusion (CFVO) is frequently found in patients with chronic venous insufficiency. The iatrogenic form, secondary to either central catheter or surgery, is very rare but highly symptomatic. Classical compression therapy barely improves the clinical status of these patients, making them suitable candidates for an interventional procedure for venous recanalization.We report here three consecutive cases of iatrogenic CFVO referred to our outpatient clinic because the disease had an impact on daily life activities. We detail the recanalization procedure, the Doppler control and the short-term outcome.In each case, endovascular recanalization required rigid material (rigid guide or Colapinto needle) to cross the fibrous adhesions before angioplasty could be performed with stenting. The procedure required two attempts in each case, underlining its complexity, but eventually enabled effective recanalization. No major complication occurred per- or post-procedure. One month later, a duplex Doppler control confirmed the permeability of the common femoral vein. The patients had experienced rapid and significant symptom improvement.Patients suffering from severe chronic venous insufficiency caused by iatrogenic CFVO can benefit from endovascular recanalization. Although these procedures may be complex due to the extensive fibrosis at the Scarpa and require specialized equipment, no major complications were observed. Patency of the recanalization persisted at least one month after the procedure. Symptom relief was good.

Acid stimulation and scale squeezing are generally well-established hydraulic well intervention practices, although methods for delivering such treatments specifically to deepwater, subsea wells are a less mature area of application. A rig-less intervention alternative provides a more economic option for intervening on subsea wells, in comparison to traditional rig-based methods. This technical paper describes the planning and execution of a multi-service vessel (MSV)-based hydraulic intervention campaign at Chevron's Tahiti field in the U.S. Gulf of Mexico. Challenged with early-life well productivity decline and imminent injected seawater breakthrough, the Tahiti asset formed a multi-disciplinary team to develop a fit-for-purpose solution to remediate and mitigate these concerns. Acid stimulation was selected to arrest and recover well productivity, while scale squeezing was required for protection against barium sulfate scaling from the mixing of formation water and injected seawater. These treatments were to be delivered to subsea production wells in water depths of ~4,200 ft. The design basis of this hydraulic intervention system involved dual, open-water coiled tubing strings deployed from the MSV to a subsea stimulation module. This module is landed and secured subsea on a modified suction pile, allowing structural isolation from the horizontal subsea production trees. In turn, a flexible jumper from this module to a valve package and modified choke insert on the tree enabled access to the wellbore for delivery of the treatments. De-coupling the stimulation module from the tree interface alleviated the risk and complexity of removing crown plugs and imparting load forces on the tree, and denotes the ‘hybrid’ nature of the system. Design and operational phases required overcoming challenges such as coiled tubing fatigue management, unexpected loop current conditions, and deployment sequence optimization. Given the first-time deployment of this hybrid system, detailed front-end engineering and design was required for validation of an enhanced well control and emergency disconnect system, to accommodate safe execution. The 5-well campaign was executed incident-free during 2015, delivering a total treatment volume of almost 30,000 bbls, resulting in 8,500 BOPD gross initial production uplift, and cost savings of 85% in comparison to traditional rig-based methods.

High resolution, spatially resolved spectroscopy is used to study the interaction of a short 3.4 ps pulse laser at intensities between 1014 and 1017 W/cm2. The detailed lines shapes show a series of regular intensity modulations, or dips, across the spectral line. We present the analysis of the helium-like emission from these aluminium plasmas, and compare the Heβ transition to calculation. Assuming the intensity dips result from the interaction of quasi-monochromatic electric field of a strong plasma wave, we are able to infer the field strengths present and electron density. This suggests that the intensity dips are driven by the strong growth of laser-driven parametric instabilities at quarter critical density. The development of high resolution spectroscopy for the interpretation of parametric driven instabilities in short pulse laser-produced plasma is discussed.

Strong oscillating electric fields modify the emission spectra of ions and can result in the appearance of additional field-induced satellites, field ionisation, and alter spectral line shapes. In addition, these high fields may alter the atomic kinetics. Experiments observing these strong oscillating electric fields in highly ionised systems are limited. Here we describe experiments using a combination of long and short pulse lasers to look for field-induced satellites, and spectral line shape modification in uniform well-characterised plasmas. A hydrogen-like and helium-like aluminium plasma was preformed using a long-duration (∼1 ns), moderate intensity (∼10 14 W/cm 2 ) laser pulse. A second short-duration (10 ps), high-intensity (∼5×10 16 W/cm) laser pulse was propagated transversally through this plasma to locally modify the oscillating electric field. The X-ray spectra were recorded using high-dispersion, high-luminosity spectrometers providing spatial resolution. Current analysis indicates that the predicted strong field effects have not been identified.

Laboratory astroplasma physics experiments advance both our astrophysics and plasma physics knowledge. Contemporary high-energy, high-power laser technology enables us to reproduce in the laboratory the conditions of temperature and pressure that are met in extreme stellar environments. The focus is on experiments designed to address key aspects of the plasma physics occurring in supernova remnants. In this approach, a plasma physics model of the astrophysical object is identified and then scaled, and applied to a laboratory experiment. This offers the possibility of detailed measurements, which can be repeated as the input conditions are altered. Results from a scaled experiment designed to address aspects of collisionless plasma interaction in a young supernova remnant are presented. This experimental study is based on the interaction of two millimetre-scale counter-streaming laser-produced plasmas, created from exploded thin plastic foils in an intense transverse magnetic field. The dynamics of the two plasmas and their interaction are studied with, and without, magnetic fields, through spatially and temporally resolved measurements of the electron density.

Results from an experimental study of the collisionless interaction of two laser-produced plasmas in a magnetic field with applications to supernova remnant shock physics are presented. The dynamics of the two plasmas and their interaction are studied with and without magnetic field through spatially and temporally resolved measurements of the electron density. Experimental results show that counter-propagating collisionless plasmas interpenetrate when no magnetic field is present. In contrast, results obtained with the addition of a 7.5 T magnetic field perpendicular to plasma flow show density features in the interaction area that only occur when the field is present. The reason for this remains uncertain. It is suggested that this results from an increase in the effective collisionality as the magnetic field reduces the ion and electron gyroradius below the size of the experiment.

Ablation depths of stainless steel targets irradiated by 80-fs laser pulses at a flux F ≤ 40 J/cm2 (intensity ≤ 5 × 1014 W/cm2) in the presence of air at atmospheric pressure are experimentally measured. These values are lower than the theoretical predictions for metal targets in vacuum. Results are analyzed on the basis of the role of the ambient gas and of crater formation on the behavior of the ablated material.

Diabetes mellitus is an independent risk factor for peripheral artery disease. Life expectancy is 41 months for diabetic patients with an ischemic ulcer. The characteristics of diabetic arteriopathy make its treatment more difficult than in non-diabetic patients. Few data are available about the surgical treatment of arteriopathy in diabetic patients (including angioplasty or bypass), especially in case of distal arteriopathy. The choice of the procedure depends on multiple factors such as the disease localization, its extent, distal blood flow and vascular disease-related surgical risk. The principal aim of revascularisation is to restore direct flow to the foot in order to ensure wound healing and limb salvage. With percutaneous endoluminal angioplasty, limb salvage can be achieved in more than 80% of patients at 1-3 years. The percutaneous procedure is less invasive than open surgery, there are fewer complications, and morbidity and mortality rates are reduced; moreover, a second procedure remains possible in the future. With bypass surgery, the rate of limb salvage exceeds 80% at five years. Nevertheless, peri-operative mortality reaches 3% and arterial anatomy, patient-related risks factors or venous graft availability may be limitations. New endovascular techniques especially designed for the distal arteries of the lower limbs enable very distal revascularization with morbidity and mortality rates lower than with surgery.

The emission spectrum from a plasma is often used to extract information on the hydrodynamic, radiative and atomic processes which occur. As these processes are coupled, detailed interpretation of spectroscopic data is often complex and uncertain. We present an experiment and modelling study of a 'simple' hydrogen and helium-like plasma. The target and laser geometry were designed to minimise spatial gradients transverse to the plasma flow. The plasma was spatially and temporally diagnosed using Thomson scattering, X-ray imaging and spectroscopic measurements. The combination of the optical and X-ray results constrains the numerical modelling to provide a more reliable plasma diagnostic. This is essential for the interpretation of high-resolution measurements and of more complex, non 1-dimensional plasmas.

A 3.4 ps duration, high-repetition rate laser is used to create an aluminium ablation plasma at intensities between 10 15 W/cm 2 and 10 17 W/cm 2 . K-shell emission is observed from the target surface and several 100 μm in to the plume. High resolution, spatial resolved measurements of the He/5 (1s3p - 1s 2 ), Heγ (1s4p - 1s 2 ), Heδ (1s5p - 1s 2 ) and Hee (1s6p - 1s 2 ) transitions are obtained using a highly dispersive toroidal crystal spectrometer coupled to a large area charged-coupled device. This data shows unusual intensity modulations on He/( transitions. These oscillations are observed to 50 μm above the target and are found to be reproducible, and the intensity of the modulations is laser irradiance dependent.

We present here the latest results obtained with our high resolution broadband X-ray microscope. These results, both spatial and spectral, were obtained in several facilities such as Berlin's synchrotron Bessy II and LULI's laser ELFIE 100TW. The results show clearly the opportunity in high resolution microscopy that offer mirror based diagnostics.

A Velocity Interferometer for Any Reflector (VISAR) [1, 2] and a Streaked Optical Pyrometer (SOP) [3] were implemented on the “Ligne integration Laser” (LIL) facility. Spatial resolution as good as 10 μm in the target plane and velocity resolution as good as 0.1 km/s can be achieved. Several campaigns were performed in 2010 involving various experimental setups and physical processes: Boron EOS, Pre-compress H2 with special setup of diamond anvil cell and Shock coalescence. This feedback will be of a great help for the Laser Megajoule facility (LMJ) VISAR design.

We use the LIL (Ligne d'Integration Laser ) facility to study the coalescence of two planar shocks in an indirectly-driven planar sample of polystyrene. This experiment represents the preliminary stage of the future shock-timing campaign for the Laser Megajoule (LMJ). The main objectives are to validate the experimental concept and to test the numerical simulations. We used a gold spherical hohlraum to convert into X-ray the 351 nm wavelength laser pulse and to initiate the two shocks in the sample. To access time resolved shock velocities and temperature, we used two rear-side diagnostics: a VISAR (Velocity Interferometer System for Any Reflection) working at two different wavelengths and a streaked optical self-emission diagnostic. We observed the coalesced shock, in good agreement with the numerical simulations. We also observed a loss of signal during the first nanoseconds probably due to sample heating from the hohlraum X-ray flux.

A case of ulnar artery aneurysm in an independent roofer is reported. It is a rare disease often associated with the Hammer Hypothenar Syndrome specifically found in manual workers and athletes exposed to repetitive palmar trauma.

Every radiotherapy center has to be equipped with real-time beam monitoring devices. In 2008, the medical application group from the Laboratory of Corpuscular Physics (LPC Caen) developed an Ionization Chamber in collaboration with the company IBA (Ion Beam Applications). This monitoring device called IC2/3 was developed to be used in IBAs universal irradiation head for Pencil Beam Scanning (PBS). The objectives presented in this article are to characterize the IC2/3 monitor in the energy and ux ranges used in protontherapy. The equipment has been tested with an IBAs cyclotronable to deliver proton beams from 70 to 230 MeV. This beam monitoring device has been validated and is now installed at the Westdeutsches Protonentherapiezentrum Essen protontherapy center (WPE, Germany). The results obtained in both terms of spatial resolution and dose measurements are at least equal to the initials speci cations needed for PBS purposes. The detector measures the dose with a relative precision better than 1% in the range 0.5 Gy/min to 8 Gy/min while the spatial resolution is higher than 250 m. The technology has been patented and ve IC2/3 chambers were delivered to IBA. Nowadays, IBA produces the IC2/3 beam monitoring device as part of its Proteus 235 product

The X-ray diffraction diagrams of a coarse grained pure BaTiO3 ceramic have been recorded as a function of the applied electric D.C. field. This field was perpendicular to the X-ray incoming surface. The experimental device used allows to record diffraction diagrams while the electric field step by step increases. The intensity ratio of the 002 line over the 200 line increases with the applied electric field. The evolution of the X-ray diffraction line intensities is in correlation with the first polarization curve of the ferroelectric ceramic. These results evidence a contribution of the 90° ferroelectric domains pattern to the X-ray diffraction diagram of BaTiO3.

We report a rare case of single cervical metastasis of breast cancer. Bone metastases are the most frequent in breast cancer. Early diagnosis combined with the new therapeutic advances have considerably improved the quality of life and increased the survival. Imaging plays a great role in the diagnosis, particularly scintigraphy and radiography, but sometimes also CT and MRI. The treatment is currently not standardized and it combines hormone therapy, chemotherapy, radiotherapy, and/or surgery.

International audience; In this paper, the authors show how high power static converters contribute to the voltage quality in railways. The first part of the paper gives an overview of power electronics solutions currently used by French National Railways and Swiss Federal Railways such as frequency converter for 15 kV/16.7 Hz system and line voltage booster or unbalance compensator for 25 kV/50 Hz system. Operating results for such devices are presented. The second part of the paper is dedicated to future trends in railway power supply. Innovative solutions concerning DC or AC systems are proposed. In each case, prototypes and experimental results are presented.

International audience; We present experiments performed with the LULI2000 nanosecond laser facility. We generated plasma jets by using specific designed target. The main measured quantities related to the jet such as its propagation velocity, temperature and emissive radius evolution are presented. We also performed analytical work, which explains the jet evolution in some cases.

Diabetes mellitus is an independent risk factor for peripheral artery disease. Life expectancy is 41 months for diabetic patients with an ischemic ulcer. The characteristics of diabetic arteriopathy make its treatment more difficult than in non-diabetic patients. Few data are available about the surgical treatment of arteriopathy in diabetic patients (including angioplasty or bypass), especially in case of distal arteriopathy. The choice of the procedure depends on multiple factors such as the disease localization, its extent, distal blood flow and vascular disease-related surgical risk. The principal aim of revascularisation is to restore direct flow to the foot in order to ensure wound healing and limb salvage. With percutaneous endoluminal angioplasty, limb salvage can be achieved in more than 80% of patients at 1-3 years. The percutaneous procedure is less invasive than open surgery, there are fewer complications, and morbidity and mortality rates are reduced; moreover, a second procedure remains possible in the future. With bypass surgery, the rate of limb salvage exceeds 80% at five years. Nevertheless, peri-operative mortality reaches 3% and arterial anatomy, patient-related risks factors or venous graft availability may be limitations. New endovascular techniques especially designed for the distal arteries of the lower limbs enable very distal revascularization with morbidity and mortality rates lower than with surgery.

Highly ionized aluminium plasmas created using long (nanosecond) and short (picosecond) duration laser pulses are studied using a combination of high resolution X‐ray spectroscopy and computational modeling tools. The experiments are designed to be simple and the emission spectra well characterized so that detailed observation of strong, single frequency electric fields effects can be observed and studied. Strong oscillating electric fields can modify the emission spectra of ions by altering spectral line shapes, through ionization processes, and the appearance of field‐induced satellite lines. However, field‐induced effects are expected to be weak, thus high dispersion, high luminosity spatially resolving spectrometers are employed. Initial results are discussed and an example of a possible field induced modification of a spectral line shape is presented.

Helium‐like aluminium (Z=13) plasmas created using long (nanosecond) and short (picosecond) duration laser pulses at intensities between 5 × 1013 and 5 × 1016 W/cm2 were studied using a combination of optical and X‐ray spectroscopy methods and computational modeling tools. The experiments were designed to ensure that the K‐shell emission spectra from the aluminium plasmas was measured in detail and that the spectra could be reproduced through a combination of hydrodynamic, atomic kinetic, and radiation transport models. Detailed spectral line shapes, with high spectral and spatial resolution, were recorded in an attempt to positively observed single frequency electric fields effects due to the application of a strong laser field, and due to strong laser‐driven plasma waves. Spectral line shape modification due to laser‐driven plasma waves was observed, yet there is no evidence for direct laser field effects. Experimental procedures and the computational work are outlined, the observation of modulated inte...

Laboratory experiment is an attractive method of exploring the plasma physics that may occur in solar and astrophysical shocks. An experiment enables repeated and detailed measurements of a plasma as the input conditions are adjusted. To form a scaled experiment of an astrophysical shock a plasma physics model of the shock is required, and the important dimensionless parameters identified and reproduced in the laboratory. A laboratory simulation of a young supernova remnant is described. The experiment uses the interaction of two millimetre‐sized counter‐streaming laser‐produced plasmas placed in a strong transverse magnetic field to achieve this scaling. The collision‐free dynamics of the two plasmas and their interaction are studied with and without the magnetic field through spatially and temporally resolved optical measurements. Laboratory astroplasma physics experiments using high‐energy, high‐power laser technology enables us to reproduce in the laboratory the conditions of temperature and pressure that are met in extreme stellar environments.

Results from a scaled, collision-free, laser-plasma experiment designed to address aspects of collisionless plasma interaction in a high-plasma β supernova remnant (SNR) are discussed. Ideal magneto-hydrodynamic scaling indicates that the experimental plasma matches the SNR plasma at 500 ps. Experimental data show that the magnetic field can alter the plasma density profile when two similar plasmas interact in a colliding geometry. These results are not explained by magnetic-field pressure; they do, however, suggest magnetic field penetration that localizes the plasma particles to the Larmor radius, which appears smaller than the size of the experiment and the particle mean-free paths and may thus increase the effective collisionality of the interacting plasma system.

Presented are interferometric results of the interaction of two plasmas without and with a magnetic field. This study is based on the collision-free interaction of two millimetre-scale, counter-streaming plasmas — a proposed experimental simulation of shock production in a supernova remnant. This collision-free interaction is compared with a separate set of experiments with an external 7.5 T magnetic field applied. The interaction dynamics are inferred from spatially and temporally resolved electron density measurements, and the effect of the magnetic field on the plasma interaction is discussed.

Laboratory astro-plasma physics experiments are being designed to advance both our astrophysics and plasma physics knowledge. With current laser technology, target design and diagnostics, it is now possible to reproduce and measure the conditions of temperature and pressure usually met in extreme stellar environments. Coupled with scaled plasma physics it is possible to simulate certain aspects of astrophysical phenomena in the laser laboratory. The focus is on experiments designed to address key aspects of the plasma physics occurring in supernova remnants. In this approach ideal magneto-hydrodynamics is applied to the supernova remnant and then scaled. Matching dimensionless parameters in a laboratory experiment enables the simulation of complex astro-plasma systems offering the advantage of repeated, detailed measurements and the flexibility to alter the input conditions. Work at York has centered on developing a collisionless plasma experiment. The experiment involves a magnetic field, and two laser-exploded plasmas to make possible a laboratory study of the interaction between a supernova remnant and the interstellar medium. These experiments and the analysis are discussed.

TiB2 coatings were deposited by hydrogen reduction of TiCl4 and BCl3. The objective was to correlate process variables with thermodynamic equilibrium calculations, deposition kinetics, coating structure and properties. Particular emphasis was given to obtaining deposits having appropriate oxidation resistance to protect C/SiC composites. Films, obtained at moderate temperature (800°C), acted as self-healing external barriers below the microcracking temperature of the outer SiC coating used as primary oxygen protection.