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International audience; Ion stopping experiments in plasma for beam energies of few hundred keV per nucleon are of great interest to benchmark the stopping-power models in the context of inertial confinement fusion and high-energy-density physics research. For this purpose, a specific ion detector on chemical-vapor-deposition diamond basis has been developed for precise time-of-flight measurements of the ion energy loss. The electrode structure is interdigitated for maximizing its sensitivity to low-energy ions, and it has a finger width of 100 μm and a spacing of 500 μm. A short single α-particle response is obtained, with signals as narrow as 700 ps at full width at half maximum. The detector has been tested with α-particle bunches at a 500 keV per nucleon energy, showing an excellent time-of-flight resolution down to 20 ps. In this way, beam energy resolutions from 0.4 keV to a few keV have been obtained in an experimental configuration using a 100 μg/cm2 thick carbon foil as an energy-loss target and a 2 m time-of-flight distance. This allows a highly precise beam energy measurement of δE/E ≈ 0.04%–0.2% and a resolution on the energy loss of 0.6%–2.5% for a fine testing of stopping-power models.

A prototype of a picosecond x-ray streak camera has been developed and tested by Commissariat a l’Energie Atomique et aux Energies Alternatives to provide plasma-diagnostic support for the Laser Megajoule. We report on the measured performance of this streak camera, which almost fulfills the requirements: 50-μm spatial resolution over a 15-mm field in the photocathode plane, 17-ps temporal resolution in a 2-ns timebase, a detection threshold lower than 625 nJ/cm2 in the 0.05–15 keV spectral range, and a dynamic range greater than 100.

Streak cameras are widely used to record the spatio-temporal evolution of laser-induced plasma. A prototype of picosecond X-ray streak camera has been developed and tested by Commissariat a l’Energie Atomique et aux Energies Alternatives to answer the Laser MegaJoule specific needs. The dynamic range of this instrument is measured with picosecond X-ray pulses generated by the interaction of a laser beam and a copper target. The required value of 100 is reached only in the configurations combining the slowest sweeping speed and optimization of the streak tube electron throughput by an appropriate choice of high voltages applied to its electrodes.

Since the first experimental campaign conducted in 2014 with mid field Gated X-ray Imager (GXI) and two quadruplets (20 kJ at 351 nm) focused on target, the Laser MegaJoule (LMJ) operational capability is still growing up. New plasma diagnostics have been implemented: a large field 2D GXI, two broadband x-ray spectrometers (called DMX and miniDMX), a specific soft x-ray spectrometer and a Laser Entrance Hole (LEH) imaging diagnostic. A series of experiments have been performed leading to more than 60 shots on target. We will present the plasma diagnostics development status conducted at CEA for experimental purpose. Several diagnostics are now under manufacturing or development which include a Streaked Soft X-ray Imager (SSXI), an Equation Of State (EOS) diagnostic suite (“EOS pack”), a Full Aperture BackScattering (FABS) diagnostic, a Near Backscattered Imager (NBI), a high resolution 2D GXI, a high resolution x-ray spectrometer, a specific set of two polar hard x-ray imagers for LEH characterization and a set of Neutron Time of Flight (NTOF) detectors. We describe here the diagnostics design and performances in terms of spatial, temporal and spectral resolutions. Their designs have taken into account the harsh environment (neutron yields, gamma rays, electromagnetic perturbations, debris and shrapnel) and the safety requirements.

The Laser Megajoule (LMJ) facility located at CEA/CESTA started to operate in the early 2014 with two quadruplets (20 kJ at 351 nm) focused on target for the first experimental campaign. We present here the first set of gated x-ray imaging (GXI) diagnostics implemented on LMJ since mid-2014. This set consists of two imaging diagnostics with spatial, temporal, and broadband spectral resolution. These diagnostics will give basic measurements, during the entire life of the facility, such as position, structure, and balance of beams, but they will also be used to characterize gas filled target implosion symmetry and timing, to study x-ray radiography and hydrodynamic instabilities. The design requires a vulnerability approach, because components will operate in a harsh environment induced by neutron fluxes, gamma rays, debris, and shrapnel. Grazing incidence x-ray microscopes are fielded as far as possible away from the target to minimize potential damage and signal noise due to these sources. These imaging diagnostics incorporate microscopes with large source-to-optic distance and large size gated microchannel plate detectors. Microscopes include optics with grazing incidence mirrors, pinholes, and refractive lenses. Spatial, temporal, and spectral performances have been measured on x-ray tubes and UV lasers at CEA-DIF and at Physikalisch-Technische Bundesanstalt BESSY II synchrotron prior to be set on LMJ. GXI-1 and GXI-2 designs, metrology, and first experiments on LMJ are presented here.

Resume Le Staphylococcus lugdunensis a ete decrit a Lyon en 1988. C’est un staphylocoque a coagulase negative responsable d’infections diverses, souvent graves en particulier en cardiologie ainsi qu’en attestent les nombreuses publications a ce sujet. Cette gravite semble due a des facteurs de virulence particuliers associes a des possibilites importantes d’adhesion, malgre une bonne sensibilite aux antibiotiques. Les publications de la litterature sont rares en ce qui concerne les infections sur protheses articulaires, et plusieurs font etat d’echecs en l’absence d’ablation des implants. Ce germe est assez facile a identifier a l’aide de la galerie Api Id 32 Staph (Bio Merieux SA). Nous analysons 7 cas retrouves sur prothese osteo-articulaire entre 1991 et 2005. Quatre infections chroniques ont subi un traitement classique par ablation reimplantation, trois fois en deux temps, une fois en un temps associee a une antibiotherapie adaptee, conduisant a 4 resultats satisfaisants. En revanche, nous avons observe 3 echecs sur 3 cas operes precocement par lavage plus antibiotherapie, deux apres infection secondaire hematogene probable, un autre apres infection postoperatoire precoce.

Within the framework of its researches on Inertial Confinement Fusion (ICF), the “Commissariat a l’Energie Atomique et aux Energies Alternatives” (CEA) studies and designs advanced X-ray diagnostics in order to probe dense plasmas produced by Laser facilities. The final goal for those diagnostics is to be used during experiments on the Laser Megajoules french facility (LMJ) at Bordeaux. We present two types of advanced monochromatic High Resolution X-ray Imaging microscopes (HRXI) who have high spatial resolution capability (3-6 μm) and high efficiency. The first microscope so-called MERSSIX consists of two toroidals mirrors mounted into a Wolter type geometry and working at grazing incidence. Non-periodic multilayer (depth graded) mirrors were developed with special coatings designed to provide broadband X-ray reflectance in the 1 - 22 keV energy range. Associated to this Wolter microscope a potential monochromatic third mirror coated with a multilayer stack can be used for monochromatic application in that range. The second microscope is composed of a transmission gold Fresnel Phase Zone Plate (FPZP) and a narrow bandwidth multilayer mirror. We present an experimental study with X-ray plasma-source and a complete characterization of the X-ray optics on the synchrotron radiation facility BESSY II. Potentialities (a few μspatial resolution monochromatic images) and complementarity of these two monochromatic HRXI are discussed. The design of the MLs for each microscope is detailed.

Generation of unipolar and bipolar pulses by using high- and medium-voltage silicon rectifier diodes is achieved. These components are provided by the French Atomic Energy Commission (CEA). Furthermore, these devices work in the linear mode of photoconducting switches. Generation of electrical unipolar pulses with an amplitude of 10.7 kV and a full-width at half-maximum of 300 ps by using only 1.2 mJ of optical power is demonstrated. This energy value is 10-100 times less than usually published during the past decades. Furthermore, the linear mode running of these devices permits to synchronize several generators with a precision as low as 2 ps. This low timing jitter is useful for bipolar generators in order to control their spectrum with high precision, i.e., bipolar pulses of 3 kV peak-to-peak have been generated with a cycle duration of 400 ps and an optical energy of 1 mJ

By using photoconductive semiconductor switches in the linear mode, we achieve generation of electrical pulses of duration between 43 and 300 ps with a peak voltage between 150 and 10700 V. Moreover, these generators can be synchronised with a precision lower than 5 ps and they need only 1.2 mJ of optical energy. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 121–125, 2006; Published online in Wiley InterScience www.interscience.wiley.com). DOI 10.1002/mop.21282

The time resolved crystal x-ray spectrometers called SXDHR-lt of the Ligne d’Integration laser is presented. It is necessary to calibrate all x-ray sensitive elements of diagnostics before using them in laser matter interaction experiments. In particular, crystals need to be calibrated. Measurements of the integrated coefficient of reflection of a beryl cylindrical crystal used in this spectrometer were performed with synchrotron radiation and with an x-ray tube and are presented. A test of the homogeneity of the reflection of the crystal was also performed. Aging or accidental pollution of x-ray diagnostics installed around target chambers is always possible. This happened to the DMX broadband spectrometer installed on the OMEGA Laser Facility at the University of Rochester (Laboratory for Laser Energetics) and this changed the spectral sensitivity of its channels. The evolution over time of the x-ray sensitivity needs to be critically assessed and if necessary x-ray sensitive elements will need to be recalibrated.

Introduction et but de l’etude Le regime vegetalien exclut la viande, le poisson, les produits laitiers, les œufs et le miel. Les etudes concernant ce regime alimentaire concluent au benefice d’une reduction moderee des risques de mortalite par cardiopathie ischemique. Le but de notre etude etait de calculer les desequilibres nutritionnels induits par ce regime alimentaire grâce a un logiciel innovant. Materiel et methodes L’etude des apports nutritionnels est realisee grâce a un logiciel informatique cree par les auteurs incluant les donnees de la table de composition nutritionnelle des aliments de l’Anses (Agence nationale de securite de l’alimentation, de l’environnement et du travail). Nous avons selectionne des recettes vegetaliennes et elabore nos calculs a partir des portions individuelles theoriques definies par le GERMCN (Groupement d’etude des marches en restauration collective et de nutrition). L’etude est realisee sur 14 jours avec un apport moyen de 2 000 kilocalories et chaque journee comporte trois repas : le petit dejeuner, le dejeuner, le diner, soit 42 menus. Nous avons additionne aux calculs des apports nutritionnels alimentaires, les apports en nutriments des boissons du petit dejeuner et d’un litre d’eau. En tout, nous avons obtenu pour cinquante nutriments repertories, une estimation de leur consommation quotidienne. Nous avons compare chacune des valeurs obtenues aux recommandations nutritionnelles connues et en vigueur. Resultats et analyse statistique Les apports nutritionnels quotidiens sont inferieurs aux apports nutritionnels conseilles (ANC) pour chaque nutriment presente dans le Tableau 1 . Nos resultats soulignent egalement les carences en acide oleique (75 % des ANC) et en omega 3 (60 % des ANC). Le rapport ω6/ω3 est de 11. Conclusion Les resultats de notre etude theorique, compares a ceux de la litterature, retrouvent les memes carences nutritionnelles en calcium, en omega 3, en acide oleique, en zinc, en iode, en vitamine B12 et vitamine D. Par ailleurs, notre logiciel met en evidence des carences averees en vitamine B2 et B5 qui n’ont pas ete repertoriees jusqu’a present. Le rapport ω6/ω3 est plus faible que celui de la population generale francaise mais il reste eleve. Nos calculs theoriques pourraient eventuellement orienter les etudes de terrain dans les mesures en micronutriments pour ce type de population. Nos resultats appuient la necessite d’une supplementation appropriee.

In high flux (1013–15 W/cm2) laser-plasma interaction, a large part of the incoming laser energy is radiated into soft x-rays. To determine both the shape of this spectrum and the conversion efficiency, we have designed and tested an absolutely calibrated broadband soft x-ray spectrometer with a high temporal resolution (100 ps). The detector in this spectrometer is a new coaxial x-ray diode coupled with a fast single shot oscilloscope (French IN7100 with 7 GHz frequency response cutoff). Both absolute calibrations (x-ray response of diodes) and relative calibrations (filters and mirrors) have used the French synchrotron beam lines at Laboratoire pour l’utilisation du Rayonnement Electromagnetique (LURE) in Orsay. The initial version of this instrument was first successfully implemented on laser plasmas experiments at the Phebus facility in France and an improved version is now operating at the Omega laser facility in Rochester, New York. The emitted x-ray spectrum is absolutely measured in 18 broad bands...

Teicoplanin was used in three hospitals over 6 years in 112 cases of bone or joint infection and the results were reviewed retrospectively. Teicoplanin was used at a dose of 400 mg/day, after a 3-day loading regimen, in combination with other agents, usually netilmicin at the beginning of the treatment. Most infections were chronic (mean duration = 20.9 months) and had failed previous antibiotic or surgical treatment. Gram-positive organisms were isolated in 120/137 identified strains (64 methicillin-resistant Staphylococcus aureus or coagulase négative Staphylococci) and all were susceptible to teicoplanin except one (intermediate for NCCLS norms). Median of follow-up was 17.3 months. The final outcome was clinical cure in 89/98 evaluable cases (91%). There were one improvement, four failures and four recurrences. Adverse events occurred in 11 patients (10%) but did not require any change in treatment. Despite the limitations of a retrospective study, teicoplanin appeared to be effective, well tolerated and easy to use with only one daily injection.RéSUMé: Une étude rétrospective, non comparative, de l'utilisation de la teicoplanine sur 112 cas d'infection ostéo-articulaire pendant 6 ans dans trois hopitaux Français est rapportée. La teicoplanine a été utilisée à la dose de 400 mg/j, après une dose de charge de 3 jours, en association avec d'autres antibiotiques (le plus souvent la netilmycine en début de traitement). Ces infections étaient chroniques (durée d'évolution moyenne de 20,9 mois) et avaient déjà fait l'objet de traitements antérieurs médicaux ou chirurgicaux. Cent vingt cocci gram positif étaient retrouvés sur les 137 souches isolées (64Staphylococus Aureus ou Epidermidis résistant à la methicillin) et tous sauf une (intermédiaire selon les normes NCCLS) étaient sensibles à la teicoplanine. Après une durée de suivi moyenne à 17,3 mois, 89 des 98 cas evaluables (91 %) étaient considérés comme guéris. On retrouvait également 1 amélioration, 4 échecs et 4 récurrences. Un effet secondaire a été noté chez 11 patients (10 %) mais n'a jamais necessité un changement de traitement témoignant ainsi de la bonne tolérance observée avec cette molécule facile à utiliser gràce à une seule injection par jour.

High-resolution, high-sensitivity X-ray imaging is a real challenge in laser plasma diagnostic to attain reliable data in high-energy density plasma experiments. In this context, ultra-high-intensity lasers generate hot and dense plasma but only in a small volume. An experiment has been performed at the LULI2000 laser facility to diagnose such plasma conditions from thermal spectroscopic data. To image the emission zone plasma's Al Heβ, a Fresnel-lens-based X-ray imager has been developed. It features a 846 μm-diameter Fresnel Phase Zone Plate (FPZP) and a Pd/B4C multilayer mirror (thickness d = 5.1 nm). This association can be used between 1500 eV and 2100 eV. The FPZP's efficiency was measured on a synchrotron facility (SOLEIL) and its spatial resolution in a laser facility (EQUINOX). The mirror reflectivity was measured on the synchrotron facility BESSY II. With experimental conditions, the system resolution reaches 3.8 ± 0.6 μm with an adequate efficiency in the 1800 eV-1900 eV energy range with a solid angle of 9 × 10-6 sr. Consequently, a FPZP is an excellent optics setup for high-resolution quasi-monochromatic X-ray imaging and provides a good collection angle. Bragg-Fresnel lenses, based on the principle of FPZP and mirrors, are currently designed for an X-ray imager at the Laser MegaJoule facility.

An electrically calibrated bolometer designed to measure VUV and soft X-ray radiation in tokamaks was installed at the end of the calibration beam line used by CEL-V at the LURE synchrotron. Low-noise electronics and an adequate data acquisition enabled absolute measurements of power densities as low as 1 μW/cm2. Power density measurements are presented. At the same location several soft X-ray detectors used in laser-plasma interaction studies were installed and their absolute calibration was performed (photocathodes, photodiodes, etc.). Calibration results are presented and compared with a Henke model for photocathode response.

This imaging system aims at recording images of the core size and shape of an imploding deuterium-tritium (DT) microballoon on LMJ inertial confinement fusion (ICF) experiments. Image acquisition is difficult due to the harsh surrounding created by the fusion reaction, which affects system specifications. This one is made of a scintillator, an optical relay, and a CCD camera shielded from the surrounding. The system was tested on different facilities at CEA/DIF, where a spatial resolution of 120 μm was achieved and gamma dose up to 20 rad effects were measured. Setup and performed test are described.

International audience; An ultra wideband radar system based on a coherent emission of an ultra-wideband antenna array using photoconductive switching devices is proposed. The triggering process is obtained by the excitation of semiconductor samples in linear mode using a picosecond laser source. The emitting antenna system and the receiving antenna developed by the Research Institute XLIM present some specific qualities suitable for radiation and measurement of ultrashort pulses. The optical control of the sources allows to sum the radiated power and to steer the transient radiation beam accurately. The experiments realized with this optoelectronic array validate these two concepts. Another way of improving these systems is proposed. It involves using bipolar pulse generators.

A high-resolution x-ray imager (HRXI) devoted to laser-plasma experiments combines two state-of-the-art technologies developed in France: a high-resolution x-ray microscope and a high-speed x-ray streak camera. The resulting streaked imager achieves spatial and temporal resolutions of approximately 5 microm and approximately 10 ps, respectively. The HXRI has recorded enhanced spatial and temporal resolution radiographs of indirectly driven targets on OMEGA. This paper describes the main features of the instrument and details the activation process on OMEGA (particularly the alignment). Recent results obtained on joint CEA/LLE radiographic OMEGA experiments will also be presented.

In this paper, we report on the latest experimental results on UV-visible multichannel streak cameras for pulse shape measurement on CEA Laser Megajoule facility. Two main characteristics of these instruments were studied: linear dynamic range and signal-to-noise ratio. With a standard PHOTONIS P820PSU bilamellar streak tube working at -10kV, a linear dynamic range of 240 was measured simultaneously in 7 channels at a 25 ns sweep duration. This value is adequate for the measurement of a high contrast laser pulse. Nevertheless, the signal-to-noise ratio at the bottom of the channel dynamic range is not sufficient to reach the requirements on the power measurement accuracy (better than few percents rms). This would require that the maximum output peak current of the P820 streak tube (0.25 mA @ - 10 kV) be improved by a factor of 5. Finally, the streak cameras that we deploy will have to be fully calibrated.

This article describes x-ray imaging with grazing-incidence microscopes, developed for the experimental program carried out on the Ligne d'Integration Laser (LIL) facility [J. P. Le Breton et al., Inertial Fusion Sciences and Applications 2001 (Elsevier, Paris, 2002), pp. 856-862] (24 kJ, UV-0.35 nm). The design includes a large target-to-microscope (400-700 mm) distance required by the x-ray ablation issues anticipated on the Laser MégaJoule facility [P. A. Holstein et al., Laser Part. Beams 17, 403 (1999)] (1.8 MJ) which is under construction. Two eight-image Kirkpatrick-Baez microscopes [P. Kirkpatrick and A. V. Baez J. Opt. Soc. Am. 38, 766 (1948)] with different spectral wavelength ranges and with a 400 mm source-to-mirror distance image the target on a custom-built framing camera (time resolution of approximately 80 ps). The soft x-ray version microscope is sensitive below 1 keV and its spatial resolution is better than 30 microm over a 2-mm-diam region. The hard x-ray version microscope has a 10 microm resolution over an 800-microm-diam region and is sensitive in the 1-5 keV energy range. Two other x-ray microscopes based on an association of toroidal/spherical surfaces (T/S microscopes) produce an image on a streak camera with a spatial resolution better than 30 microm over a 3 mm field of view in the direction of the camera slit. Both microscopes have been designed to have, respectively, a maximum sensitivity in the 0.1-1 and 1-5 keV energy range. We present the original design of these four microscopes and their test on a dc x-ray tube in the laboratory. The diagnostics were successfully used on LIL first experiments early in 2005. Results of soft x-ray imaging of a radiative jet during conical shaped laser interaction are shown.

Staphylococcus lugdunensis was described in Lyon in 1988. This coagulase-negative staphylococcus is the cause of diverse infections which are often severe, particularly in the field cardiology where numerous publications are available for reference. The severity of S. lugdunensis infection is related to specific virulence factors associated with significant adherence properties despite good sensitivity to antibiotics. Publications dealing with joint prosthesis infections are sparse and the reports available have noted failure of treatment unless the prosthesis is removed. S. lugdunensis can easily be identified with an Api Id 32 Staph battery from BioMerieux. We analyzed seven cases of joint prosthesis infections with S. lugdunensis observed between 1991 and 2005. Four chronic infections were managed using the classical schema of implant removal then reimplantation, using a two-stage procedure for three and a single stage for one. Combined with adequate antibiotic treatment, this method was successful in all four cases. We did however have three cases of failure (two were secondary to a probable hematogenic infection and the other an early postoperative infection); these cases were operated on by early lavage and antibiotic therapy without success.

The laboratory XLIM has developed an impulse optoelectronic ultra-wide band antenna array for UWB radar applications. This paper presents this system in which photoconductive switches generating high voltage monopolar pulses and UWB antennas are associated. The control of the releasing delay of the sources via optic provides to sum the radiation power and to steer the transient radiation beam accurately. The experiments realized with this optoelectronic array validate these two concepts. We also propose another way of improvement of these systems by using bipolar pulse generators.

We propose an ultra wide band radar system based on a coherent emission of an ultra-wide band antenna array using photoconductive switching devices. The triggering process is obtained by excitation of semiconductor samples in linear mode using a picosecond laser source. The emitting antenna system and the receiving antenna developed by our research laboratory, present some specific qualities suitable for radiation and measurement of ultra-short pulses

Nous presentons des resultats concernant la generation d'impulsions electriques ultra large bande de fortes puissances par photoconduction. Le regime lineaire utilise a permis d'engendrer des impulsions d'une largeur de 300 ps a mi hauteur avec des tensions crete de plus de 10 KV. La gigue temporelle associee a ce regime est inferieure a 5 ps et necessite une energie optique inferieure a celle deja publiee. Nous avons egalement engendre des impulsions bipolaires a spectre ajustable.

We demonstrate the generation of multikilovolt bipolar picosecond pulses using an optically activated travelling wave generator into 50Ω load. The spectral content of the output electrical pulse can be modified to favour or reduce low-frequency components. Bipolar pulses of 450 ps of duration with more than 3 kV of peak voltage are produced. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1645–1648, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21713

We achieved the generation of 300ps FWHM electrical pulses with 130ps rise time and 10700V amplitude by using an innovative technology based on doped semiconductive substrate. The linear mode running of these elements permitted their temporal synchronisation and optical activation with low input optical energy. Picosecond bipolar pulses with several kilovolts were also generated with this technology.

We achieved the generation of unipolar and bipolar electrical picosecond pulses by using semiconductor switches in linear mode. Electrical pulses of hundreds volts to several thousands volts were obtained: in example unipolar pulses of about 11kV with duration of 300ps (full width at half maximum) were obtained and bipolar pulses of 3kV peak-to-peak with cycle duration of 450ps were done. Besides the linear mode running of these doped silicon semiconductors permitted to synchronise several generators and it allows adjustment of the bipolar pulse spectrum by using the frozen wave generator principle. So we demonstrated the feasibility of high voltage ultra-wideband electrical pulse generation with less optical energy than already published in the linear mode.

We achieved the generation of unipolar and bipolar ultra-wideband electrical pulses by using a photoconductive device. It relies on a doped silicon substrate which is used in the linear mode with less optical energy than usually published. This running mode allows the synchronisation of several sources with a timing jitter less than 5 ps. However it permits to control the low frequency components of the bipolar generator by means of the synchronisation of two photoconductors. So we generated unipolar pulses from 43 ps to 300 ps of duration (full width at half maximum: FWHM) with peak voltage up to 10700 V and bipolar pulses between 200 ps and 450 ps of cycle length with 3000 V of peak voltage.

In this paper, we have demonstrated and studied the operation of a photoconductive switch delivering 100 ps to 300 ps electrical pulses with high peak voltage and using low energy for optical gating. The synchronization of 4 generators permitted to develop an ultra wide band radar system for mine detection application.

Surveillance of nosocomial surgical site infections was instituted in our department in June 1991. We report our first nine years experience.This study concerned the first 9 years (June 1991-June 2000) of a surveillance program designed to monitor nosocomial surgical site infections in our orthopedic surgery department. During this period 9,696 patients underwent surgery, including 2745 for hip replacements and 1016 for knee replacements. The diagnosis of infection was based on the Centers of Disease Control criteria. Beginning in 1997, the program was widened to include all indications for prophylactic antibiotics, being limited before that time to indications for arthroplasty and spinal surgery.The overall rate of infection was 1.25%; 0.55% for hip arthroplasty and 1.77% for knee arthroplasty. The rate of infection among hip surgery patients over the last 5 years was much higher for prosthesis revision (2.37%) than for first-intention implantations (0.16%). The majority of the isolated strains were Gram-positive (84%) including Staphylococcus sp. found in 65% of the cases. Multiple-strains were found in 23% of the infections. The rate of infection improved very significantly over the last five years both for knee arthroplasty and spinal surgery. The rate remained unchanged for hip arthroplasty.This 10-year survey enabled us to analyze the difficulties encountered and pinpoint errors or insufficiencies in data recording. We were also able to identify measures to be taken concerning patient follow-up. The improvement in the rate of infection over time appears to be multifactorial, undoubtedly related to wider use of prophylactic antibiotics, progress in hygiene and sterilization methods with institution of a quality assurance program, and team awareness.Surveillance of nosocomial infections is a recommended practice. We have found that the information provided can be beneficial if the data is statistically sound, pointing out the need for progress in patient follow-up.

This paper gives an overview of works undertaken at CEA/DIF in high speed cinematography, optoelectronic imaging and ultrafast photonics for the needs of the CEA/DAM experimental programs. We have developed a new multichannel velocimeter, and a new probe for shock breakout timing measurements in detonics experiments. A brief description and a recall of their main performances will be made. We have implemented three new optoelectronic imaging systems, in order to observe dynamic scenes in the ranges of 50 - 100 keV and 4 MeV. These systems are described, their main specifications and performances are given. Then we describe our contribution to the ICF program: after recalling the specifications of LIL plasma diagnostics, we describe the features and performances of visible streak tubes, X-ray streak tubes, visible and X-ray framing cameras and the associated systems developed to match these specifications. At last we introduce the subject of components and systems vulnerability in the LMJ target area, the principles identified to mitigate this problem and the first results of studies (image relay, response of streak tube phosphors, MCP image intensifiers and CCDs to fusion neutrons) related to this subject. Results obtained so far are presented.

The detailed measurement of the free electron laser micropulse with a streak camera is carried out on the Super-ACO storage ring for the first time. In this measurement, we reveal the temporal form of the laser micropulse in the cw and the Q -switched laser operation modes. In some operating conditions, the temporal distribution of the laser micropulse is different from a Gaussian. We have also measured the laser micropulse width ( σ RMS ≈ 26 ps). This value is compared to the previously obtained results and it shows a good agreement.

57 cases of infected total hip prosthesis treated by removal of the implant and implantation of unncemented prosthesis, were studied to evaluate functional and sepsis results.57 patients treated by reimplantation of an uncemented total hip prosthesis after removal of the infected prosthesis were observed. 16 patients underwent a single-stage exchange, 41 a two-stage reimplantation. 46 cases were analysed for infection findings (clinical, radiological and biological assessment) and only 34 cases for functional evaluation (PMA scale, Harris score) with a mean follow-up of 6.6 years. The antibiotic therapy was adapted to each patient but generally, the treatment was prolonged.At follow-up time (which might be too short in time), only 2 patients had a recurrence of infection. One had a single-stage exchange (reoperated by two stage exchange with a good final result at 6 years follow-up), the other a two-stage exchange. In both cases we found that postoperative antibiotic therapy was inadequate. Functional results were better with PMA scale (23 good results of 34) than with Harris score (14 excellent or good results only). 5 patients were reoperated for mechanical implant failure.Since 1991, we adopted a standardized procedure to treat chronic infected total hip prosthesis including: routine preoperative aspiration of symptomatic prosthesis; removal of the implant and around debridement followed at a later date (6 weeks) by reimplantation using uncemented implants (hydroxyapatite coated implant). Postoperative antibiotic therapy has to be massive (parenteral bitherapy for at least 21 days after each operative stage) and has to last 6 months after reimplantation. This procedure seems reliable and corroborate the validity of two-stage treatment. The using of uncemented implants allows a good bone reconstruction and does not seem to increase the risk of septic recurrence.It is quite difficult to find a hard and fast rule in infected prosthesis treatment, because many factors can influence results. The proposed procedure seems reliable, even if antibiotherapy is long and hard, but requires a strong collaboration between bacteriologist infectiologist and surgeon.

In an effort to improve the performances of streak cameras, experimental and theoretical studies were conducted, aimed at measuring the noise in a camera. This would be achieved through the evaluation of the camera's noise factor and by additionally pointing out the possible sources of noise. It was shown for our camera, a TSN 506 Thomson camera, that the noise factor is due partly to signal loss (factor 1,8) and partly to noise addition (factor 2,6). Moreover, noise was shown to be additive and Poissonian, mostly due to shot noise and photoelectric conversions.

We present and discuss time resolved spectra (KeV range) of solid density plasmas produced by the interaction of clean high intensity laser pulses (400 fs, 0.53 im light) with solid and foil targets at intensities between 1018 W/cm2 and 1020 W/cm2. Results have been obtained with the new PX1 x-ray streak camera which hasa temporal resolution of 750 fs in the KeV x-ray range.Keywords: X-ray Spectroscopy, Femtosecond temporal resolution, High density plasmas, Ultrashort laser producedplasmas. 1. INTRODUCTION Over the past seven years, a revolution has occurred in our ability to produce extremely compact, highaverage power and high intensity lasers. These recent progresses are the direct results of the use of both a newamplification technique, namely the technique of Chirped Pulse Amplification (CPA)[1}, and new broadbandamplification media such as Ti:sapphire and Cr:LiSAF[2]. Laser pulse lengths are now compressed down todurations of less than 100 femtosecond. Although the laser energy is not so high, large intensity can be achieved dueto extremely short pulse duration and very good focusability. Furthermore extremely high repetition rates are nowcurrently achieved[3}. These advances have made possible the production and the study ofhot solid density plasmaswhich are unique sources of ultrafast x-ray pulses[4,5]. These short pulses of x-rays could be a very useful tool to

The multi-image framing camera based on gated MicroChannel Plates (MCPs), used in ICF programs, allows to obtain a sequence of 2D images in the x-ray range with gating times smaller than 100 ps and spatial resolution better than 20 pl/mm. After using such devices from different factories, we decided to build our own tube. Our choice is motivated by the great fragility of the tube, consequent to both bad vacuum during the experiment and moisture due to frequent air launching, and by the mastery of the technology which is necessary to repair rapidly such apparatuses. The characteristics of the tube, particularly shutter time and spectral response, must be known as exactly as possible. Consequently we describe in these pages the method used to measure a shutter time of about 75 ps and we appraise the errors due to the FWHM and the spatial unstability of the UV laser pulse employed to illuminate the front side of the MCP. The measurement of the spectral sensitivity, determined by experiments with synchrotron radiation on the storage ring SUPERACO in Orsay (France), shows a response in the energy band 2 - 5 keV different from the one measured with the gold vacuum-deposited photocathode on the MCP.

High precision and high dynamic range measurements are required to properly characterize the pulseshape in ICF laser systems. The dynamic range and precision of the measurements that can be made with streak tubes is determined by the number of photoelectrons that can be transported to the recording screen per channel and per temporal sample of the signal. They are limited by the overall current that the tube can deliver without distorting the signal. In order to build tubes with the large dynamic ranges required by this application, we need to understand at what current density level the tube response becomes nonlinear. We present results of experiments made by using a laser illuminating several streak tubes at various intensities. We show that charge depletion in the photocathode can occur in pulsed mode and limit the signal to levels well below that where space charge induced nonlinearities appear. The use of scientific grade CCD's for recording the streak traces has allowed the introduction of a new method to measure the absolute current in the tube. A 2D PIC electron optics code has been used to simulate the propagation of the beam in the input diode (photocathode/accelerating electrode) and in the drift region (accelerating electrode/screen) of a bilamellar streak tube. We compare the numerical results with the experiments. We conclude by comparing the bilamellar and classical electron optics tubes and show the advantages of the former tube design for this application.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

To interpret the experimental results in laser matter interaction experiments, the absolute spectral response of soft x‐ray detectors is often needed. For this purpose CEL‐V uses calibration lines of synchrotron radiation of SUPER‐ACO at the LURE. The energy of output photons can be selected from 50 eV to 1000 eV. The output photon flux is absolutely calibrated with a bolometer or a soft x‐ray photodiode. Then we measure the response of the studied detector installed at the same location. Measurements of quantum efficiencies of photocathodes (Al and CsI on Al) and of the response of a thinned CCD are presented versus photon energy.

High resolution x-ray streak cameras using tubes with bilamellar electron optics have been developed for a long time in CEL-V, in collaboration with Philips Components (now Philips Photonics) for the tubes. The last improvements on their electronics, implemented on the commercial cameras developed with ARP, have allowed us to get the best results from the tubes, especially for the quality of their focusing. We have already been able to verify that the performance of the C850X camera in the UV range is as good as expected from calculations. New experiments made in the x-ray range show that it is also true in the x-ray range. We describe the results of these experiments and we also show preliminary results obtained with the C750X camera (which is identical to C850X except that its deflection structure is a meander travelling wave line instead of conventional plates) which show that the sweep speed reached gives us a 1 ps temporal resolution in the x-ray range.

The laser integration line (LIL) located at CEA-CESTA is equipped with x-ray plasma diagnostics using different kinds of x-ray components such as filters, mirrors, crystals, detectors, and cameras. The CEA-DAM of Arpajon is currently developing x-ray calibration methods and carrying out absolute calibration of LIL x-ray photodetectors. To guarantee LIL measurements, detectors such as x-ray cameras must be regularly calibrated close to the facility. A new x-ray facility is currently available to perform these absolute x-ray calibrations. This paper presents the x-ray tube based high energy x-ray source delivering x-ray energies ranging from 0.9 to 10 keV by means of an anode barrel. The purpose of this source is mainly to calibrate LIL x-ray cameras but it can also be used to measure x-ray filter transmission of plasma diagnostics. Different x-ray absolute calibrations such as x-ray streak and framing camera yields, x-ray charge-coupled device quantum efficiencies, and x-ray filter transmissions are presented in this paper. A x-ray flat photocathode detector sensitivity calibration recently performed for a CEA Z-pinch facility is also presented.

High resolution X-ray streak cameras built around bilamellar tubes have been developed for a long time in CEL-V2. The C850X camera is the last step of those studies. We describe here the different versions of the camera; we also present theexperimental results (temporal resolution 2 ps in conjunction with a dynamic spatial resolution > 15 lp/mm ) obtained inENSTA on a 60 fs UV laser, which match our theoretical predictions.The improvements of the C850X electronics have also been implemented on C750X (theP750X tube of that camerahas the same structure as that of C850X, but its deflection plates are replaced by a 5Of meander stripline, which allows highersweep speeds).We present the status of that development, the improvements accomplished on the sweep circuit and the first resultsobtained with that device. 1 - INTRODUCTION Streak cameras used in laser interaction experiments at Centre dEtudes de Limeil-Valenton have been the subject of years of tube development with the help of the PHILIPS COMPONENTS3 company. In particular the new concept of

A recording of temporal reference on picosecond streak camera images requires to transmit laser pulses of different wavelengths through optical fibers (O.F.) onto streak cameras. We describe the O.F. network installed on the PHEBUS laser to provide streak cameras and photomultipliers with a 200 ps pulse. We also describe the tests performed on various fibers to evaluate their transmission (? = 0.35 tim) and on photocathodes to get the best photons-electrons conversion efficiency in open X-rays tubes. Then we describe the experimental test set up also installed to easily check the sweep linearity and speed and also the amplitude response of X-rays cameras, using this fiducial system. We show practical results of those tests, and some laserplasma interaction experimental results.

High resolution x-ray streak cameras based on bilamellar tubes have been developed for picosecond laser interaction studies performed at CEL-V. We now have a whole family of such cameras: C 850, C 851 (in which the tube features a reflection photocathode), and C 750 (where deflection plates of the tube are replaced by a 50-Ω meander stripline, which allows higher sweep speeds).

The broadband x-ray emission of a target irradiated by a laser can be used to check the calibration of detectors. At CEA-DIF we have a tabletop picosecond laser facility called EQUINOX with 0.3 J at 800 nm. The laser is focused inside a target chamber onto a solid target and produces bright radiation in the 100-2000 eV spectral range. The x-ray source is routinely monitored with a pinhole camera for source dimension measurement and with x-ray diodes for flux measurement. In addition an x-ray transmission grating spectrometer, a crystal spectrometer, and a single count charge coupled device camera measure the x-ray spectrum between 100 eV and 15 keV. The absolute calibration of those sets of spectrometers allows us to fully characterize x-ray emission spectra. Typical duration is less than 100 ps. The spectrum can be tuned by changing target material, pulse length, and x-ray filters. An application to checking the calibration of x-ray diodes used in the broad band spectrometer DMX with single shots will be presented.

The diagnostic designs for the Laser Megajoule (LMJ) will require components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiations, and, in some cases, debris and shrapnel, at levels several orders of magnitude higher than those experienced today on existing facilities. The lessons learned about the vulnerabilities of present diagnostic parts fielded mainly on OMEGA for many years, have been very useful guide for the design of future LMJ diagnostics. The present and future LMJ diagnostic designs including this vulnerability approach and their main mitigation techniques will be presented together with the main characteristics of the LMJ facility that provide for diagnostic protection.

The Laser Integration Line (LIL) is part of the Laser Megajoule (LMJ) project. The LMJ installation, which is of the National Ignition Facility (NIF) class, will deliver 1.8MJ at 0.35μm wavelength on target with 60 quadruplets of elementary beams. The energy on target of LIL is 30kJ corresponding to one quadruplet, it is housed in a separate building and has its own experimental setup. Target diagnostics have been progressively installed in the LIL target area. Energy and imaging diagnostics as well as the broadband and high resolution spectrometers have been fabricated in the frame of a unique industrial contract. Optical pointers are used to align the diagnostics to the target. The supervisory system controlling the diagnostics configuration and data acquisition is now able to manage cooperative and Commissariat a l’ Energie Atomique (CEA) shots. The calibration data base is accessible from the processing network and will very soon include the characterization of all the streaked, gated, and charge coup...

An improved version of the initial x-ray ultraviolet spectrograph SPARTUVIX1 has been developed to record the time evolution of spatially resolved spectra in the soft x-ray range (from 30 to 300 {Angstrom}). This diagnostic can be applied to the new class of laser produced plasma experiments now performed in order to better understand the physical evolution of x-ray indirect drive plasmas. Instead of a one-dimensional streak camera used for the first version, a new widely used 2-D soft x-ray time gated imager allows us to follow the time evolution of the spatially resolved soft x-ray spectra. This instrument was designed for plastic foam soft x-ray opacity measurements. The soft x-rays, emitted by an auxiliary radiography laser plasma source, are transmitted through the foam and dispersed into two parts (+1 and {minus}1 order of the transmission grating). Each dispersed spectrum is placed on two different gated striplines of the soft x-ray imager and thus recorded at two different times (exposure time 300 ps, adjustable interframe 600 ps). The spatial resolution is obtained with a slit added in front of the spectrograph, that images the plasma onto the detector with a magnification ratio of 15 and a spatial resolution of 50 {mu}m.more » A detailed description of this instrument and the main results obtained for two different plastic foam opacity measurements (undoped and doped with chlorine) will be presented. This work is supported by European Community Contract No. CEE/CHGF-CT-92-0016. {copyright} {ital 1997 American Institute of Physics.}« less

Respiratory tract infections in intensive care units have a high fatality rate, perhaps as a result of the poor diffusion into bronchial secretions of aminoglucosides given by a systemic route. Endotracheal administration of aminoglycosides has been advocated but the optimal dosage remains to be determined. To investigate this problem we studied 13 patients free of renal failure and 6 patients with renal failure. Netilmicin was given by continuous endotracheal infusion in a daily dosage of 3 to 30 mg/kg. A good correlation was found between infused doses and serum concentrations; very high bronchial secretion concentrations were consistently found. There is a significant risk of accumulation in patients with renal failure. The characteristics of the respiratory tract secretions had no influence on the passage of netilmicin into the bloodstream. The dosages we advocate on the basis of our results are 8 mg/kg/day in patients free of renal failure and 4 mg/kg/day in patients with renal failure; serum netilmicin concentrations should not exceed 1 microgram/ml.