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This paper presents a new type of slow-wave Lower Hybrid Current Drive launcher, based on the Slotted Waveguide Antenna (SWA) concept, which is particularly attractive for the use in future magnetic fusion reactors. A low power prototype SWA has been designed for the COMPASS tokamak at IPP-Prague. The Radio-Frequency (RF) design of this low power prototype is based on hybrid electromagnetic calculations, combining Finite-Element-Method, Mode Matching and RF network computations. Two SWA prototype samples have been manufactured with different slot geometries, and they have been first measured in air. The RF design of the low power SWA prototype and its feeding circuit is discussed in this manuscript; measurements in air are also illustrated.

Introduction La tomoscintigraphie (TEMP) couplee a la tomodensitometrie (TDM) est devenue indispensable en scintigraphie osseuse. Le recalage des images entre les donnees TDM et TEMP peut etre difficile si le patient n’a pas ete strictement immobile lors de l’acquisition. Les acquisitions centrees sur les mains sont particulierement sujettes a ces decalages entre TEMP et TDM, car il est difficile de maintenir parfaitement immobile les poignets et l’ensemble des doigts pendant une duree d’environ 20 minutes. L’impression 3D additive permet la realisation rapide de prototypes a tres faible cout. Elle permet donc de realiser des moules de contention multiples, voire personnalises. Materiel et methode Un set de cales de contention de differentes tailles en acide polyactique (PLA) a ete realise par impression 3D additive. La modelisation des cales a ete effectuee sur logiciel libre FreeCAD, puis l’impression realisee sur une imprimante Prusa I3 MK2S (Prusa Reasearch). Les parametres d’acquisition TEMP etaient de 15 sec/projection, 60 projections, soit 15 minutes d’acquisition TEMP, suivie de l’acquisition TDM de l’ensemble du volume explore en TEMP. Les examens ont ete effectues sur camera GE Discovery 670 et Siemens Intevo 6. La presence d’un decalage entre les donnees TDM et TEMP, pour chaque doigt, pour le poignet et pour l’avant-bras, a ete cotee visuellement. Resultats Dix patients successifs devant realiser une scintigraphie comportant une acquisition TEMP-TDM centree sur les mains ont realise l’examen avec les mains placees dans les cales adaptees a leur morphologie. Les donnees ont ete comparees a dix patients successifs ayant realise leur examen avant la creation des cales. L’ensemble des doigts etait parfaitement recale pour 80 % des examens realises avec cales. Pour les deux patients presentant un decalage, ce dernier concernait une seule phalange. Seuls 40 % des examens realises sans cale etaient parfaitement recales ; deux patients avaient un decalage complet dans plusieurs axes de l’ensemble des volumes, rendant tout recalage manuel impossible. Conclusion Pour un cout tres modique de quelques dizaines d’euros, la realisation d’un set de cales de contention permet d’ameliorer la qualite du recalage entre donnees TEMP et TDM, facilitant ainsi l’interpretation des examens multi-modalites des extremites.

The aim of WEST [1] [2] is to master long pulses (> 30s and up to 1000s) and submit ITER like tungsten divertor tiles to power fluxes of 10 MW/m2. To reach these goals, the Tore Supra Lower Hybrid Current Drive system (LHCD) constituted by two launchers with an injection power capability of 7MW/1000s has been upgraded to meet WEST new environment (diverted plasma, new launchers positions). In particular, the LH1 Full Active Multi-junction launcher (FAM) has been toroidally reshaped to match the new magnetic configuration. The poloidal curvature of the plasma has also been optimized to guarantee good coupling properties of the waves. During the last experimental campaign (October-December 2018), we obtained 30s repetitive pulses with a LH power of 2.7 MW (more than 2 hours of plasma during the experimental campaign) and 43 discharges with a total LH power from 4-5.3 MW. This paper describes the results obtained in term of coupling for both launchers. Thanks to Infra-Red (IR) monitoring it also assesses the reshaping of LH1 in terms of thermal loads due to supra-thermal electrons on the launcher edges. During the upcoming experimental campaign, the IR coverage will further improve allowing assessing the LH2 Passive Active Multi-junction launcher (PAM) thermal loads.

High-power continuous-wave radio-frequency (RF) systems in the megawatt range are commonly used in nuclear fusion experiments. Such kinds of RF systems being rather rare, Master’s students do not know how these systems are used in practice – even students engaged in nuclear fusion courses. This is the reason why, as part of the French and European Master’s in fusion physics and technologies, dedicated practical work on topics related to plasma RF heating are proposed to students. Over a few days, these students discover how to perform RF measurements and succeed in characterizing real-scale components used in plasma RF heating experiments. This paper details four hands-on approaches which have been conducted over eight years with several tens of students having no prior knowledge in RF engineering.

This paper reports a fishnet hyperbolic metamaterial that mimics the electromagnetic properties of magnetically confined plasma. These electromagnetic properties are strongly anisotropic and different from any conventional material, therefore cannot be mimicked by bulk materials. The structure is made of a stack of thin copper grids spaced by Rohacell foam. We numerically and experimentally show that this kind of structuration matches well the properties of a homogeneous plasma. This solution breaks a long-lasting bottleneck and will accelerate the development of high-frequency heating systems to be used in nuclear fusion.

The WEST-project ( W -tungsten E nvironment in S teady-state T okamak) involves equipping Tore Supra with a full tungsten divertor, capable of withstanding heat load of 10 MW/m2 in steady-state conditions, in discharges sustained by Lower Hybrid Current Drive (LHCD). The LHCD generator, recently upgraded to deliver 9.2 MW/1000 s, is equipped with sixteen TH2103C klystrons powering two launchers. The WEST transformation involves reducing the plasma volume, thus moving the launchers ∼10 cm closer to the tokamak centre. The toroidal curvature of the launchers no longer fits the plasma curvature due to the strong magnetic field ripple effect, leading to a degradation of the LH wave coupling, especially with the Full Active Multijunction Launcher (FAM). The toroidal curvature radius of the FAM launcher mouth will therefore be reshaped from 1700 mm to 2300 mm. The machining process is described in this article. In order to improve the coupling of the LH wave, the local gas injection has been modified to help to meet the requirement of 7 MW/1000 s of LH power coupled to the plasma in the WEST scenarios. Finally, the curvature radius of the waveguide septa are rounded to minimize the excitation of suprathermal electrons near the plasma edge, which can induce high power loads on the plasma facing components.

This year Tore-Supra celebrated its 25 years of operation. During this long time, a number of technologies have been developed. First of all, it was mandatory to develop reliable superconducting magnets at ∼1.8 K, with superfluid helium as an efficient coolant. For the production of steady state discharge, three types of radio frequency (RF) additional heating systems have been developed: 1) lower hybrid current drive; 2) ion cyclotron resonance heating; and 3) electron cyclotron resonance heating. To cope with long lasting discharges (up to 380 s × 2.8 MW) and large RF additional heating power (12.3 MW × 3 s), actively cooled (AC) plasma facing components were deployed in Tore-Supra for the first time in a tokamak environment. Tore-Supra is now being modified into a D-shape axisymmetric tokamak with AC tungsten main chamber walls and a divertor, the WEST project (W-for tungsten-environment in steady-state tokamak). This new facility has the objective to offer ITER a test bed for validating the relevant AC metallic technologies in D-shape H-mode plasmas. In contrast to other metallic devices, such as JET and ASDEX Upgrade, WEST will rely only on the RF additional power systems. A set of plasma scenarios have been identified, ranging from a high total RF power scenario up to 15 MW in 30 s, to a high fluence scenario of 1000 s with up to 10 MW of injected RF power. These scenarios are able to reproduce ITER relevant conditions of steady state heat loads of 10-20 MW/m2, to test tungsten AC divertor technologies with relevant power heat fluxes and particle fluence.

To develop Continuous Wave (CW) high power klystrons for fusion experiments, calorimetric matched loads absorbing the RF power are necessary. To test and adjust the parameters of the new klystrons TH2103C [1] able to produce 700 kW/CW at a frequency of 3.7 GHz for upgrading the RF power available in Tore Supra LHCD transmitter, SPINNER GmbH has successfully developed, in collaboration with the CEA, and manufactured a water load capable to absorb the RF power with a Voltage Standing Wave Ratio (VSWR)

A new Passive Active Multijunction (PAM) Lower Hybrid heating and Current Drive (LHCD) launcher, has been successfully manufactured and tested on Tore-Supra (TS). The design and the fabrication of this new actively cooled launcher based on the PAM concept, as the present ITER LHCD design, is a major component of the TS CIMES project (Components for the Injection of Matter and Energy in Steady-state), and will play a key role in the TS near term program. To achieve 1000 s pulses with a power flux of 25 MW/m 2 the PAM launcher has been designed for steady state (CW) operation (active cooling) with the objective of coupling 2.7 MW of LHCD power to the plasma at 3.7 GHz with a parallel index N ∥ = 1.7 ± 0.2. The launcher has achieved its qualifications tests, i.e. low power Radio Frequency measurements, vacuum and hydraulic leak tests, and has been installed on Tore-Supra tokamak in September 2009. It is commissioning on plasma started a month later, quickly achieving its design performance of 2.7 MW on a 35 s pulse. After a technical description of the PAM, this paper presents an overview of the project phases (RF optimization, manufacturing and qualification) and concludes with the first experimental results of the PAM.

Highly Charged Ions (HCI) approaching surfaces at nm distances are known to extract a very large number of electrons from the target. Over dielectric surfaces, the positive holes left following the removal of the electrons cannot be immediately neutralized, thereby locally inducing a huge stress and creating permanent surface modifications on very small dots. We present in this paper experiments on the structural transformations induced by irradiation with HCI of graphite and diamond surfaces characterized using the Atomic Clock Property of the Hollow Atoms (ACPHA) technique.

The use of metal(salen) complexes in the asymmetric syntheses of cyanohydrins and amino acids have been developed as important and reliable methods of obtaining these highly versatile chiral intermediates. Thus, we have developed a number of titanium and vanadium(salen) complexes, with ligands derived from (R,R)-cyclohexane-1,2-diamine, which catalyze the synthesis of enantiomerically enriched 0-protected cyanohydrins from various carbonyl compounds and cyanide sources. Nickel, copper and cobalt(salen) complexes have also been developed, as catalysts for the preparation of non-racemic amino acids under phase-transfer conditions.

CEA/IRFM is conducting R\&D efforts in order to validate the critical RF components of the 5 GHz ITER LHCD system, which is expected to transmit 20 MW of RF power to the plasma. Two 5 GHz 500 kW BeO pill-box type window prototypes have been manufactured in 2012 by the PMB Company, in close collaboration with CEA/IRFM. Both windows have been validated at low power, showing good agreement between measured and modeling, with a return loss better than 32 dB and an insertion loss below 0.05 dB. This paper reports on the window RF design and the low power measurements. The high power tests up to 500kW have been carried out in March 2013 in collaboration with NFRI. Results of these tests are also reported. In the current ITER LHCD design, 20 MW Continuous Wave (CW) of Radio-Frequency power at 5 GHz are expected to be generated and transmitted to the plasma. In order to separate the vacuum vessel pressure from the cryostat waveguide pressure, forty eight 5 GHz 500kW CW windows are to be assembled on the waveguides at the equatorial port flange. For nuclear safety reasons, forty eight additional windows could be located in the cryostat section, to separate and monitor the cryostat waveguide pressure from the exterior transmission line pressure. These windows are identified as being one of the main critical components for the ITER LHCD system since first ITER LHCD studies [1] [2] [3] or more recently [4] [5] , and clearly require an important R\&D effort. In this context and even if the LHCD system is not part of the construction baseline, the CEA/IRFM is conducting a R\&D effort in order to validate a design and the performances of these RF windows. In order to begin the assessment of this need, two 5 GHz 500 kW/5 s pill-box type windows prototypes have been manufactured in 2012 by the PMB Company in close collaboration with the CEA/IRFM [6]. The section 2 of this paper reports the RF and mechanical design of a 5 GHz window. Some features of the mechanical design and the experimental RF measurements at low power are reported in section 3. High power results, made in collaboration with NFRI, are detailed in section 4. The development of CW windows is discussed in the conclusion. 2-RF AND MECHANICAL DESIGN The proposed 5 GHz RF window is based on a pill-box design [2] , i.e. a ceramic brazed in portion of a circular waveguide, connected on either side to a rectangular waveguide section. Typical design rules of thumb of such device are circular section diameter about the same size of the diagonal of the rectangular waveguide (cf. FIGURE 1). Without taking into account the ceramic, the circular section length is approximately half a guided wavelength of the circular TE 11 mode, in order for the device to act as a half-wave transformer. Once optimized, taking into account the ceramic, matching is correct only for a narrow band of frequency and is very sensitive to the device dimensions and the ceramic relative permittivity. The heat losses in the ceramic, which have to be extracted by an active water cooling, depends on the inside electric field topology and of ceramic dielectric loss (loss tangent). Undesirable modes due to parasitic resonances can be excited in the ceramic volume, raising the electric field and, 20th Topical Conference on Radio Frequency Power in Plasmas, Jun 2013, Sorrento, Italy. 2014

International audience; The nuclear fusion research goal is to demonstrate the feasibility of fusion power for peaceful purposes. In order to achieve the conditions similar to those expected in an electricity-generating fusion power plant, plasmas with a temperature of several hundreds of millions of degrees must be generated and sustained for long periods. For this purpose, RF antennas delivering multi-megawatts of power to magnetized confined plasma are commonly used in experimental tokamaks. In the gigahertz range of frequencies, high power phased arrays known as " Lower Hybrid " (LH) antennas are used to extend the plasma duration. This paper reviews some of the technological aspects of the LH antennas used in the Tore Supra tokamak and presents the current design of a proposed 20 MW LH system for the international experiment ITER.

The tokamak Tore Supra (TS) has been operated since 1988 in Cadarache Centre. With the Composants Internes et Limiteur project, it will be the only machine to be able to exploit the Advanced Tokamak Regimes in steady state operation with three heating systems ICRH, LH, ECRH. The injected RF power in the Torus is a very important parameter of the total energy balance of TS, for this reason we need the best possible knowledge of these powers. The analysis and the explanation of the different RF techniques at low power which have been used in TS on the three RF systems will be described. Principles of the different measurement systems are given. The calibration methods of these systems are discussed and the present status of the calibration uncertainties of the RF measurements is analysed. Finally, when the generators are connected to a dummy load, RF measurements are compared with the calorimetric power measurements. This study allows preparation of improvements of these systems which will be used in these next steps: Composants pour l'Injection de Matiere et d'Energie Stationnaire project (B. Beaumont, Tore Supra steady state power and particles injection: the CIMES project, in: Proceedings of the 21st SOFT, Madrid, 2000).

The characterization of semiconductor heterostructures from their mobility spectra has originally been proposed, some 12 years ago, as an improvement of Hall effect measurements. However, the application is far from being trivial and often leads to the occurrence of extra peaks without any physical interpretation. They are generally referred to as “mirror peaks” and are interpreted in terms of computational artifacts. The present paper comments upon such peaks from a set of data concerning van der Pauw test structures. Our main conclusion is that from an experimental point of view, the transverse component (ρxy) of the resistivity tensor is more precisely determined than the longitudinal one (ρxx). Thus, we are left with the possibility of artifacts within the experimental procedure. Starting from an adjustment of all available information (ρxx and ρxy), a preferential adjustment of ρxy leads to the disappearance of “mirror peaks”. As a matter of example, we report the study of an InP-based bilayered structure and show how the mobility spectrum evidences the highly conducting channel of a HEMT device.

We report the results of capacitance-voltage (C-V) and Deep Level Transient Spectroscopy (DLTS) measurements performed upon a Ga0.47In0.53As/InP quantum well structure. At room temperature, a conduction-band offset ΔEc=(200±10)meV and charge densities σI=±(3±1)*1011 times the electronic charge per cm2 have been measured from C-V experiments. At lower temperature (T≤150K) we have observed an important decrease of the band-offset, considerably larger than a pure thermal effect. We have shown that the explanation lies in the presence of a high concentration of deep traps located at the well-barrier interfaces. Two species A and B have been detected through DLTS experiments with activation energies EtA=90 meV and EtB=195 meV, respectively. The filling of these trap levels at low temperature lowers the band offset from 200 to 120 meV, owing to band repulsion effects.

The paper reports a study of electrical properties of InP layers ( < 3 μm thick) epitaxied by MOVPE and HVPE. The technique used is the so-called mobility spectrum method in which the maxima of carrier density are determined as a continuous function of mobility. A reduced conductivity tensor (RCT) adjustment allows to improve the accuracy in the determination of density and mobility values. In such layers, a high mobility channel, corresponding to the bulk material, is evidenced. However, low mobility channels are also detected and are interpreted in terms of the presence of defects (n-type for MOVPE and p-type for HVPE) at the substrate-layer interface. In the case of thin epitaxied layers on insulating substrate, the classical Hall data leads to a nonsignificant mean value of mobility while mobility spectrum technique improves the understanding of electrical properties at the layer-substrate interface.

Tore Supra is dedicated to long pulse operation at high power, with a record in injected energy of 1 GJ (2.8 MW × 380 s) and an achieved capability of 12 MW injected power delivered by 3 RF systems: Lower Hybrid Current Drive (LHCD), Ion Cyclotron Resonance Heating (ICRH) and Electron Cyclotron Resonance Heating (ECRH). The new WEST project (W [tungsten] Environment in Steady-state Tokamak) aims at fitting Tore Supra with an actively cooled tungsten coated wall and a bulk tungsten divertor. This new device will offer to ITER a test bed for validating the relevant technologies for actively cooled metallic components, with D-shaped H-mode plasmas. For WEST operation, different scenarii able to reproduce ITER relevant conditions in terms of steady state heat loads have been identified, ranging from a high RF power scenario (15 MW, 30 s) to a high fluence scenario (10 MW, 1000 s). This paper will focus on the evolution of the RF systems required for WEST. For the ICRH system, the main issues are its ELM resilience and its CW compatibility, three new actively cooled antennas are being designed, with the aim of reducing their sensitivity to the load variations induced by ELMs. The LH system has been recently upgraded with new klystrons and the PAM antenna, the possible reshaping of the antenna mouths is presently studied for matching with the magnetic field line in the WEST configuration. For the ECRH system, the device for the poloidal movement of the mirrors of the antenna is being changed for higher accuracy and speed.Tore Supra is dedicated to long pulse operation at high power, with a record in injected energy of 1 GJ (2.8 MW × 380 s) and an achieved capability of 12 MW injected power delivered by 3 RF systems: Lower Hybrid Current Drive (LHCD), Ion Cyclotron Resonance Heating (ICRH) and Electron Cyclotron Resonance Heating (ECRH). The new WEST project (W [tungsten] Environment in Steady-state Tokamak) aims at fitting Tore Supra with an actively cooled tungsten coated wall and a bulk tungsten divertor. This new device will offer to ITER a test bed for validating the relevant technologies for actively cooled metallic components, with D-shaped H-mode plasmas. For WEST operation, different scenarii able to reproduce ITER relevant conditions in terms of steady state heat loads have been identified, ranging from a high RF power scenario (15 MW, 30 s) to a high fluence scenario (10 MW, 1000 s). This paper will focus on the evolution of the RF systems required for WEST. For the ICRH system, the main issues are its ELM resil...

This year TORE-SUPRA celebrated its 25 years of operation. During this long time a number of technologies have been developed [1]. First of all it was mandatory to develop reliable superconducting magnets at ∼ - 4 K, with superfluid helium as efficient coolant. For the production of steady state discharge, 3 types of Radio Frequency (RF) additional heating systems have been developed: Lower Hybrid Current Drive (LHCD), Ion Cyclotron Resonance Heating (ICRH) and Electron Cyclotron Resonance Heating (ECRH) [2]. To cope with long lasting discharges (up to 380 s × 2.8 MW) and large RF additional heating power (12.3 MW × 3 s), Actively Cooled (AC) Plasma Facing Components (PFC) were deployed in TORE-SUPRA for the first time in a Tokamak environment. TORE-SUPRA is now being modified into an axisymmetric tokamak with actively cooled tungsten main chamber walls and a divertor, the WEST project (W - for tungsten - Environment in Steady-state Tokamak) [3]. This new facility has the objective to offer ITER a test bed for validating the relevant actively cooled metallic technologies in D-shape H-mode plasmas. In contrast to other metallic devices such as JET and ASDEX, WEST will rely only on RF additional power systems. A set of plasma scenarios have been identified, ranging from a high total RF power scenario up to 15 MW during 30 seconds, to a high fluence scenario of 1000 seconds with up to 10 MW of injected RF power. These scenarios are able to reproduce ITER relevant conditions of steady state heat loads of 10 to 20 MW/m, to test tungsten actively cooled divertor technologies with relevant power heat fluxes and particle fluence. The paper presents the main issues regarding WEST project and especially the additional RF power injection systems (2 LHCD antennas, 3 + 4 = 7 MW continuous wave and 3 ICRH antennas, 3 × 3 = 9 MW-30 s or 3 MW-1000 s) for WEST. The front face of the LHCD antennas will be modified to account for the different plasma position and smaller toroidal field ripple, due to the more inward antenna position in the vessel. No other modifications are needed on the Passive-Active Multijunction (PAM) or the Fully-Active Multijunction (FAM) LHCD antennas, or the associated generator (2 × 8 klystrons, 600 kW each CW). Concerning the ICRH system, the main challenges are its ELM-resilience, its compatibility with continuous operation, and the interaction of the RF near fields with neighbouring plasma facing components. 3 new actively cooled antennas are being designed to be matched with an ELMs resilient electric circuit. The proposed solution is based on the JET-EP antenna and CEA prototype tested in 2007, both having identical internal conjugate-T electrical layout and a demonstrated load resilience capacity to plasma edge transients during ELMs. © 2013 IEEE.

A new concept of multijunction-type antenna has been developed, the Passive Active Multijunction, which improves the cooling of the waveguides and the damping of the neutron energy (for ITER) compared to Full Active Multijunction. Due to the complexity of the structures, prototypes of the mode converters and of the Passive-Active-Multijunction launcher were fabricated and tested, in order to validate the different manufacturing processes and the manufacturer's capability to face this challenging project. This paper describes the manufacturing process, the tests of the various prototypes and the construction of the final Passive-Active-Multijunction launcher, which entered into operation in October 2009. It has been commissioned and is fully operational on the Tore-Supra tokamak, since design objectives were reached in March 2010: 2.75 MW - 78 s, power density of 25MW/m2 in active waveguides, steady-state apparent surface temperatures < 350 °C; 10 cm long distance coupling.

New real time tools have been developed for testing new 700kW/3.7GHz/CW klystrons and for the operations on very long plasma shots. After the commissioning of the 18 series tubes on the high power test bed facility, the installation of the first 8 klystrons in the Tore Supra transmitter and the adjustment tests on load, this upgrade work has been materialized during the last 2010 campaign by a successful operation on the Full Active Multijunction (FAM) C3 antenna, with new performances: 3.5MW/40s on plasma. The RF output power control in amplitude and phase has been improved for a better control of the wave spectrum launched into the plasma. The new klystrons have no modulating anode and the high cathode voltage must be adjusted with the RF input power in order to optimize the RF output power with a minimization of the thermal power losses in the collector. A new phase correction, depending on the 3 RF output power ranges used, has been introduced. The improvements made in 2009 and 2010 on the generic phase loop and the procedures used during the real time tests of the RF transfer functions in amplitude and phase are detailed below. All RF measurements systems, RF safety systems and the RF calibration procedures have been revised in order to have the best consistency, reproducibility and with a measurement error against the calorimetry measurement lower than 10%.

The density fluctuations, modified by Lower Hybrid Wave (LHW), is analyzed in Tore Supra with reference to the injected LHW power, density and the gap between LCFS (Last Closed Flux Surface) and the PAM (passive‐active‐multijunction) launcher. The density fluctuations are measured with RF probes installed at the PAM launcher front. A density scan at nominal toroidal field (3.8 T) shows that the fluctuations rate stays nearly constant (∼50%) for 〈ne〉〈3.5×1019m−3 and with LHW power up to 2MW. However, when increasing the density above 〈ne〉〈∼4.2×1019m−3, using strong gas puffing, the fluctuation rate increases to >70% and is characterized by strong negative spikes, with typical frequency >100kHz. These are most likely originating from acceleration of electrons in the LHW near field due to parasitic absorption, as evidenced on the IR images, showing hot spots on the side limiters.

The design and overall dimensions of a RF window and a TE10—TE30 mode converter of a 5 GHz Lower Hybrid system which should be able to deliver 20 MW CW on ITER are presented. A low power mock‐up of the mode converter has been manufactured and measured. The good RF performances obtained validates the RF design of this element.

The aim of the Tore Supra tokamak is to address physics and technology issues of long pulse discharges. For this purpose, Tore Supra is equipped with two actively cooled Lower Hybrid Current Drive (LHCD) antennas (f = 3.7GHz), designed to operate in 1000s long pulses. One of these is the recently installed passive active multijunction (PAM) antenna, whose design is chosen for an LHCD system for ITER. The first experiments with the PAM antenna in Tore Supra have shown extremely encouraging results in terms of reflection coefficient behaviour and power handling. The maximum power and energy reached on the PAM, after ~500 pulses on plasma, was 2.7MW during 78s (exceeding 200MJ injected energy). In addition, 2.7MW has been coupled at a plasma‐antenna distance of 10cm. The coupling behaviour on the PAM, characterised by the fraction of reflected power (RC), shows good agreement with the predictions from the ALOHA coupling code. Full non‐inductive discharges lasting 50s have been sustained with the PAM alone, e...

Resume L'analyse de 402 observations de paludisme recense de janvier 1984 a octobre 1988 dans l'Ouest de la France au cours d'une enquete retrospective multicentrique (GERICCO ** ), montre une progression importante des cas depuis 1986 (45 cas par an en 1984 ; plus de 150 cas par an en 1988). Cette progression porte avant tout sur les acces a Plasmodium falciparum (324 cas) principalement contractes en Afrique Intertropicale (80 % des cas). 37 acces pernicieux responsables de 5 deces ont ete notes. Sans negliger l'augmentation du tourisme exotique vers ces zones d'endemie, cette progression spectaculaire est en partie due a l'extension de la chloroquino-resistance en Afrique de l'Ouest.

The upgraded 3.7 GHz Lower Hybrid Current Drive (LHCD) system for the Tore Supra (TS) tokamak is in the process of installation [1]. When complete, it will permit long pulse injection (1000s) at coupled power level up to 6, 5 MW. Steady state operation of high power RF sources and components is challenging and requires careful validation before the system can be commissioned on the tokamak.Results on the validation of CW klystrons, improvements on the RF components forming part of the power generation circuit and the development of an RF water load to sustain CW pulses under 700 kW RF power are presented.

The design and the fabrication of a new Lower Hybrid (LH) actively cooled antenna based on the passive active concept is a part of the CIMES project (Components for the Injection of Mater and Energy in Steady-state). The major objectives of Tore-Supra program is to achieve 1000 s pulses with this LH launcher, by coupling routinely >3 MW of LH wave at 3.7 GHz to the plasma with a parallel index n{sub ||} = 1.7 {sup {+-}}{sup 0.2}. The launcher is on its way to achieve its validation tests--low power Radio Frequency (RF) measurements, vacuum and hydraulic leak tests--and will be installed and commissioned on plasma during the fall of 2009.

On Tore Supra, the Lower Hybrid Current Drive (LHCD) 3.7 GHz system is being upgraded in the frame of the CIMES project. The paper describes the status of the development and manufacturing of the two main components of the project: the new klystron TH2103C and the PAM antenna.

The use of metal(salen) complexes in the asymmetric syntheses of cyanohydrins and amino acids have been developed as important and reliable methods of obtaining these highly versatile chiral intermediates. Thus, we have developed a number of titanium and vanadium(salen) complexes, with ligands derived from (R,R)-cyclohexane-1,2-diamine, which catalyze the synthesis of enantiomerically enriched 0-protected cyanohydrins from various carbonyl compounds and cyanide sources. Nickel, copper and cobalt(salen) complexes have also been developed, as catalysts for the preparation of non-racemic amino acids under phase-transfer conditions.

Diamond has the most interesting and extreme thermal, dielectric and electronic properties of semiconductors. The benefits of using diamond for power electronic switch can be illustrated by a new figure of merit. The exploration of possible device applications for this material has been motivated by the significant advances in growth and electronic technologies of diamond. Our studies are focused on two specific problems of power electronic: thermal management and high voltage switching. Indeed, diamond exhibits a unique combination of the highest electric breakdown field and thermal conduction that make it a potential candidate for power electronic packaging. Moreover, recent improvements in single crystal diamond growth have resulted in films with very high carrier mobility and high electric breakdown field that present a new interest for high power switches

Cat scratch disease is a mild pathology but diagnosis often remain difficult.A retrospective study has been conducted by the department of infectious diseases at the University hospital in Angers. Between January 1994 and October 1998, 26 observations were recorded providing the presence of three criteria out of four among the following: contact with a cat, clinical presentation and its favorable course, absence of any other cause noticed, and the presence of either a positive serology or a positive PCR, or the examination of a suggestive pathology.Fourteen men and 12 women were concerned. From a clinical point of view, the inoculation lesion was observed six times, all patients showed at least one adenopathy during their illness, 12 patients showed only an adenopathy without clinical signs. A surgical biopsy was carried out on nine patients and a diagnosis established. Bartonella henselae serology was done in all patients. Six presented a significant rate of IgG antibodies as early as the first dosage. A seroconversion was observed in four cases belatedly 1 to 2 months after the beginning of the symptomatology. The method's sensitivity was approximately 38%. A PCR search was accomplished in the pus obtained from a ganglionic puncture on 12 patients. It was positive seven times, which corresponds to a sensitivity of about 58%. In associating these two diagnostic criteria a sensitivity rate of nearly 92% was reached, the diagnosis not having been confirmed only in one case. The outcome proved to be favorable in all cases, with or without an antibiotic treatment.The association of serology and PCR in the pus permits a certain diagnosis in the majority of the cases and avoids the more aggressive biopsy.

The renin-angiotensin system (RAS) is involved in a complex mechanism that serves to preserve the blood supply to organs so that they can maintain cellular function. Angiotensin II exerts this effect, independently of the blood pressure generated, through two time-related events: a fast opening of the reserve collateral circulation and a much slower response of new vessel formation or angiogenesis. This effect is observed in rats with ligation of the abdominal aorta and in gerbils with abrupt or progressive unilateral carotid artery ligation. Inhibition of the angiotensin-converting enzyme (ACE) or the angiotensin II receptor represses this effect, and it appears that it is mediated through a non-AT1 receptor site of angiotensin II. Many tumors, both benign and malignant, express renin and angiotensin. It seems that the stimulating action of angiotensin II on angiogenesis could also be involved in preserving the blood supply to tumor cells. Administration of converting enzyme inhibitors increases survival and decreases tumor size in tumor-bearing rats. These observations support the hypothesis that the RAS, directly or indirectly, is involved in situations in which the restoration of blood supply is critical for the viability of cells and that it is present not only in normal but also in pathological conditions such as tumors. In view of the ubiquitous presence of renins and angiotensins, it is also likely to be involved in other conditions, such as inflammation, arthritis, diabetic retinopathy, and retrolental fibroplasia, among others in which angiogenesis is prominent. In addition, angiotensin II could be involved, through the counterbalance of the AT1 and AT2 receptors, in the rarefaction of blood vessels as an etiologic component of essential hypertension.

The characterization of the electromagnetic field at the electron cyclotron frequency is one important point for the ECRH installation under development at the CEA Cadarache. This characterization is based on a mathematical decomposition of the electromagnetic field over the various radiating modes of an oversized corrugated waveguide. To perform this determination, which principle is given in the paper, one has to access the amplitude and the phase of the full electric field on a plane transverse to the propagation direction. It is possible to obtain amplitude and phase diagrams of the two crossed polarization at low level. At high level, in the output of a gyrotron, one uses only thermal measurements and the phase is reconstructed from the amplitude diagrams. The paper exposes a compete validation of this method and gives and results of the high level characterization.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The increase of calcium (Ca) set point in uremic hyperparathyroid patients and its decrease with calcitriol therapy are controversial. Besides methodological differences regarding the experimental protocol for obtaining the sigmoidal curve, mainly differences in definitions of maximal PTH (peak or steady value) and of calcium set point itself have been proposed for the discrepant conclusions. However, two other explanations are possible: the various aluminum load of the patients and the dependency of Ca set point upon the basal plasma ionized calcium (PCa).Therefore the Ca set point was measured in 2 groups of patients on maintenance dialysis never exposed to aluminum, one of 7 patients with normosecretion of PTH (NPT) and the other of 8 patients with hyperparathyroidism (HPT) before and after 3 intravenous administration of 4 microg of alfacalcidol in a week. The sigmoidal curve was established during a zero Ca dialysis, without Ca replacement for the first 90 minutes and with intravenous infusion of 41 mmoles of Ca during the 150 last minutes. The curvilinear decrease of PCa induced a peak of PTH followed by a decrease while PCa was still decreasing up to the 90th minute. Therefore PTHmax was taken both at the peak and at its lower value observed at the 90th minute (steady PTHmax). Experimental determinations of the Ca set point were made using both definitions of Brown and Felsenfeld and both PTHmax values. In basal conditions, while using any of the values given by the same calculation methodology, Ca set point was not different in NPT and HPT patients. After alfacalcidol, no change in plasma PTH nor in Ca set point was observed in HPT patients. In contrast, in NPT patients alfacalcidol induced a significant decrease of plasma PTH concentrations in association with an increase in basal PCa and in Ca set point, whatever the definitions of the latter and of PTHmax. Calcitriol induced changes in Ca set point and basal PCa were correlated.1) In normocalcemic dialysis patients never exposed to aluminium hyperparathyroidism is not explained by an increased Ca set point 2) Calcitriol suppressive effect on PTH secretion is neither explained by a decrease in Ca set point. 3) Ca set point as measured in vivo does not reflect an intrinsic characteristic of the parathyroid glands since it varies with basal PCa. Better than methodological differences, this dependency may explain the discrepant conclusions between the various clinical investigations.

Toxocara canis is a common parasite in puppies. The danger to human health has not been properly established. We estimated the current incidence of this pathogen in two western districts of France, Loire-Atlantique and Maine et Loire. Blood samples from 1836 eosino-philic patients were collected and tested by an enzyme-linked immunosorbent assay (ELISA) excretory-secretoryToxocara antigen test. We obtained positive results in 22% of the cases and highly positive results in 7%. The ELISA data seemed to be age-dependent, with older patients having more positive results (P

We report a versatile method to engineer arrays of nitrogen-vacancy (NV) color centers in diamond at the nanoscale. The defects were produced in parallel by ion implantation through 80 nm diameter apertures patterned using electron beam lithography in a PMMA layer deposited on a diamond surface. The implantation was performed with CN − molecules which increased the NV defect formation yield. This method could enable the realization of a solid-state coupled-spin array and could be used for positioning an optically active NV center on a photonic microstructure.

A new concept of lower hybrid antenna for current drive has been proposed for ITER (Bibet et al 1995 Nucl. Fusion 35 1213–23): the passive active multijunction (PAM) antenna that relies on a periodic combination of active and passive waveguides. An actively cooled PAM antenna at 3.7 GHz has recently been installed on the tokamak Tore Supra. This paper summarizes the comprehensive experimental characterization of the coupling properties of the PAM antenna to the Tore Supra plasmas. In this paper, the electromagnetic properties of the antenna are measured at a reduced power (n c to 10 × n c where n c is the slow wave density cut-off, n c = 1.7 × 1017 m−3 at 3.7 GHz) and antenna phasing, the ALOHA simulations reproduce the experimental results observed on Tore Supra. In addition, reduced power reflection coefficients (n c, i.e. in the range 0.5–3 × n c. Measurement and analysis with ALOHA of the antenna–plasma scattering matrices provide explanation of the good coupling properties of the PAM antenna close to n c by highlighting the crucial role of the slow wave intercoupling between active and passive waveguides through the plasma edge. This detailed validation of the coupling modelling is an important step towards the validation of the PAM concept in view of further optimizing the electromagnetic properties of the future ITER antenna.

Fifty patients in stage IV of HIV infection (including 41 AIDS patients) were prospectively studied by echocardiography. Thirteen of them showed abnormalities: 4 had pericardial effusion, 1 endocarditis, 7 myocardial disorders and 1 primary pulmonary arterial hypertension. Pericardial effusion, also present in patients who had pleuropulmonary Kaposi's sarcoma, was not specific. Myocardial disorders concerned the diastolic function in 1 case, the segmental kinetics in 2 cases and the whole systolic function in 4 cases (3 had congestive myocardiopathy and 1 had transient systole alteration without left ventricular dilatation). The mechanism of global left ventricular disorders was multifactorial, and several hypotheses were discussed: infectious myocarditis, adrenergic or nutritional deficiency myocarditis, cardiotoxicity of antiviral drugs, common pathology with HIV encephalopathy. The prognosis of congestive myocardiopathy was poor in AIDS patients and undetermined in stage IV non-AIDS patients. Echocardiography is capable of detecting these lesions, and its use may contribute to a better care of these patients.

A new ITER-relevant lower hybrid current drive (LHCD) launcher, based on the passive-active-multijunction (PAM) concept, was brought into operation on the Tore Supra tokamak in autumn 2009. The PAM launcher concept was designed in view of ITER to allow efficient cooling of the waveguides, as required for long pulse operation. In addition, it offers low power reflection close to the cut-off density, which is very attractive for ITER, where the large distance between the plasma and the wall may bring the density in front of the launcher to low values. The first experimental campaign on Tore Supra has shown extremely encouraging results in terms of reflected power level and power handling. Power reflection coefficient −2, i.e. its design value at f = 3.7 GHz. In addition, 2.7 MW has been coupled at a plasma–launcher distance of 10 cm, with a power reflection coefficient

Background: NCT is increasingly used for operable breast cancer to allow breast conservation. Our objective was to evaluate clinical and pathological response after sequential NCT of 3 cycles of FEC 100- 3 cycles of T. This chemotherapy is currently the reference in the adjuvant setting in France.In PACS 01 trial (Roche et al. J Clin Oncol, 2006) FEC followed by T significantly improved 5 years overall survival rates (90.7%) compared to 6 FEC 100 in node-positive breast cancer. However this active combination has not yet been evaluated in NCT.Methods: 101 patients (pts) from February 2005 to September 2008 with pathologically confirmed stage II-III untreated operable breast cancer received 3 cycles (c) of FEC 100 (epirubicin 100 mg/m² + 5-fluorouracil and cyclophosphamide 500mg/m²) followed by 3 c of T (100mg/m²) every 3 weeks. pCR was defined according to Chevallier's (Am J Clin Oncol, 1993) as level 1 and 2 and to Sataloff's classification (J Am Coll Surg, 1995) as grade A. A clinical, mammography and ultrasound breast evaluation was performed at baseline, after 3 c and before surgery.Results: Median age was 52.3 years [28-72]. Median diameter of the tumor was 42 mm [14-100]. 83 pts had a ductal, 14 a lobular, 3 ductal and lobular, 1 another carcinoma. 8.9% were grade I SBR, 58.4% grade II SBR, 28.7% grade III SBR and 4% unspecified. 74 (73.3%) tumors were HR+, 9(8.9%) Her-2 + and 18(17.8%) triple negative. 55 pts (54.4%) were premenopausal.After 3 cycles of FEC 100, ultrasound objective response rate (ORR) was 15%: 13 pts had a partial response and 2 pts had a complete response.After 6 cycles of NCT, ultrasound ORR was 62.5%: 53 pts had a partial response and 7 pts had a complete response.Most frequent grade (G) 3-4 adverse events were neutropenia which occured in 16 pts (15.8%) with G 3 febrile neutropenia in 11 pts (10.9%) (G-CSF optional). Most frequent G 1-2 averse events were nausea which occured in 43 pts(42.6%), myalgia in 27 pts(26.7%) and stomatitis in 23 pts(22.8%).After the completion of NCT, 76 pts (75.2%) underwent breast-conserving surgery. 12(11.9%) achieved pCR using Chevallier's classification and 15(14.8%) using Sataloff's classification.Conclusion: Sequential NCT with FEC followed by T was active and relatively well tolerated. Breast-conserving rate appeared satisfactory. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1105.