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LASERIX est une plateforme de l’IJClab sur le campus de l’Université Paris Saclay. Le laser est une chaîne CPA de niveau 50 TW à 10 Hz. Des thématiques de recherche en rapport avec la physique des deux infinis sont menées en parallèle avec une vocation affirmée d’ouverture à la formation. Nous présentons un panorama sur les sources XUV de lumière structurée, l’accélération laser plasma et des études prospectives sur l’étude des propriétés du vide soumis à un champ électromagnétique ultra-intense.

In this article we present modelling results of the amplification of High Order Harmonics (HOH) carrying orbital angular momentum (OAM) in plasma amplifiers created from krypton gas and silver solid targets. The resulting amplified beam is characterized in terms of intensity, phase and decomposition in helical and Laguerre-Gauss modes. Results show that the amplification process conserves OAM, although some degradation is apparent. Several structures appear in the intensity and phase profiles. These structures have been characterized with our model and related to refraction and interference with the plasma self-emission. Thus, these results not only demonstrate the capability of plasma amplifiers to deliver HOH amplified beams carrying OAM but also pave the way towards using HOH carrying OAM as a probe beam to diagnose the dynamics of hot, dense plasmas.

Au travers des interrogations epistemologiques emanant de deux recits d’analyse celebres, l’homme aux loups et le cas Dick, l’auteur se propose de deconstruire le concept freudien de scene originaire pour evaluer ce a quoi la relation duelle est reductible dans l’intersubjectivite naissante. Le caractere atypique de la nevrose infantile a amene la psychanalyse a s’interesser aux soubassements de la scene originaire. Klein evoque les stades precoces du conflit œdipien en lien avec le concept de parents combines. Quant au cas Dick, il amene a s’interroger sur la pertinence du modele binaire des positions kleiniennes et de l’opportunite d’introduire la notion d’une position autistique primaire du developpement en rapport avec le concept d’objet combine. Pour finir, l’auteur dresse un tableau de l’ontogenese de la scene originaire en fonction de la dialectique bionienne contenant/contenu et en questionne les protorepresentations prenatales.

We demonstrate the production of EUV vortex beams, and vector-vortex beams merging the helical phase of a vortex and the spatially variant polarization of a vector beam, both carrying large orbital angular momentum per photon.

Mielke et al. (2021) proposed a stepwise multiple testing procedure (MTP) based on marginal p-values for rejecting at least k out of m null hypotheses. Briefly, the MTP cannot reject less than k hypotheses, but this property improves the power to reject k or more hypotheses relative to the stepdown MTP of Holm (1979). Mielke et al. discussed why such an MTP is of interest in the context of biosimilarity developments. This article describes how a slight modification of Holm's simple direct arguments can be used as an alternative to the closed-testing arguments of Mielke et al. to show the strong control of the family-wise error rate. This modification is based on a Holm-type formulation of the rejection algorithm where each step involves a single ordered p-value. With k equal to one, the stepwise MTP reduces to Holm's stepdown MTP. The MTP is valid quite generally. A version of the MTP with weights for hypotheses is also described and discussed. As in the case without weights: (a) a modification of Holm's arguments can be used; (b) with k equal to one, the MTP reduces to Holm's MTP with weights; and (c) the MTP is valid quite generally.

The synchronous control of spin and orbital angular momentum in high-harmonic generation allows us to introduce experimentally and theoretically a novel XUV structured beam with spatially-varying polarization and phase, high topological charge, and robust propagation.

We present a new Velocity Map Imaging (VMI) spectrometer based on the thick-lens configuration to be implemented at different XUV source beamlines to realize the measurements of the pulse temporal structure using the technique of laser-dressed photoionization.

PME familiale, le Laboratoire Science & Nature defend, depuis sa creation en 1972, des valeurs de respect de la nature et de ses ecosystemes. Les plantes cultivees sur les 92 hectares de son domaine, en agriculture biodynamique, sont transformees en cosmetiques et produits d’entretien. Via sa fondation d’entreprise et son reseau de conseilleres en vente a domicile, elle diffuse aupres de ses clients, de ses salaries et du grand public sa conviction que l’avenir de l’espece humaine passe par une comprehension intime de la nature.

International audience; The effects of particle correlations on the spectral broadening due to the radiator motion (Doppler broadening) are discussed for a Ni-like XUV laser line pumped in two different regimes of collisional excitation. The transient pumping for which ionic temperature is relatively low (the plasma coupling parameters is large), and the quasi steady-state pumping (QSS) for which the ionic temperature is higher and the plasma coupling parameter of the order of 1 are considered. It is shown by using classical Molecular Dynamics simulation techniques that in both cases the effect of correlations modify the radiator-motion broadened profiles and cannot be neglected in evaluating Doppler effect. This is due to the fact that the radiator velocity changes during the radiation emission resulting in a mixing of velocities in the line profile. It is also shown that this results in a homogenization of the intrinsic line profiles.

We have investigated high harmonic generation in an argon gas cell driven by two femtosecond laser pulses separated by a variable delay ranging from 500 fs to 100 ps. Experiments were performed at the LASERIX IR-EUV facility using an amplified 10 Hz CPA Ti:Sapphire laser system on a beamline delivering 50 fs pulses at 800 nm with energy up to 25 mJ. In the case of a non-zero time delay we studied the optimal conditions for equilibrated double pulse generation despite perturbation of the generating medium induced by the first pulse. We showed how high harmonic double pulse generation varies with the gas pressure, the excitation energy, the delay and the relative polarization between the two laser pulses.

We review our recent work devoted to the experimental characterization and numerical simulations of XUV laser pulses generated from hot and dense plasmas. We discuss the specific properties exhibited by few-picosecond, partially coherent pulses arising from Amplification of Spontaneous Emission. We describe our ongoing effort to develop a single-shot time-resolved measurement tool adapted to shorter, femtosecond pulses, which are foreseen with advanced seeded XUV lasers developed in several laboratories.

The derivation of simultaneous confidence regions for some multiple-testing procedures (MTPs) of practical interest has remained an unsolved problem. This is the case, for example, for Hochberg's step-up MTP and Hommel's more powerful MTP that is neither a step-up nor a step-down procedure. It is shown in this article how the direct approach used previously by the author to construct confidence regions for certain closed-testing procedures (CTPs) can be extended to a rather general setup. The general results are then applied to a situation with one-sided inferences and CTPs belonging to a class studied by Wei Liu. This class consists of CTPs based on ordered marginal p-values. It includes Holm's, Hochberg's, and Hommel's MTPs. A property of the confidence regions derived for these three MTPs is that no confidence assertions sharper than rejection assertions can be made unless all null hypotheses are rejected. Briefly, this is related to the fact that these MTPs are quite powerful. The class of CTPs considered includes, however, also MTPs related to Holm's, Hochberg's, and Hommel's MTPs that are less powerful but are such that confidence assertions sharper than rejection assertions are possible even if not all null hypotheses are rejected. One may thus choose and prespecify such an MTP, though this is at the cost of less rejection power.

Different techniques of mesh placement for cystocele repair are known. Our goal was to compare anatomical and functional outcomes of three different techniques of mesh placement over a 3-year follow-up. Between March 2003 and June 2004, 230 patients (stage 2–4 pelvic organ prolapse (POP)) were included in a prospective study. For cystocele repair, mesh was implanted either with two arms into the retropubic space (RP) or with two to four arms into the obturator foramen (TO), or fixed to the arcus tendineous fascia pelvis (FG). Patients' distribution is as follows: 142 TO, 32 RP, and 31 FG. Anatomical success (cystocele < stage 2 in the POP staging system) was clearly poorer after the retropubic free technique, with success rates of 69% (RP), 90.1% (TO), and 96.6% (FG) (p = 0.004). POP distress inventory (p

Resume Dans une approche psychodynamique et anthropologique, l’auteur aborde, a partir de vignettes cliniques, certaines modalites de relations d’objet observees dans l’anorexie mentale. Elles sont prises en compte selon trois incidences relevant du domaine de l’intrapersonnel, de l’interpersonnel et de l’intraculturel. Du point de vue intrapersonnel, la lutte contre l’avidite orale sous-tendue par la destructivite originaire a l’egard de l’objet primaire semble etre au cœur de la conflictualite intrapsychique et de la fantasmatique anorexique. L’incapacite a integrer les sentiments ambivalents a l’egard de l’objet maternant est liee a la survivance d’un surmoi precoce et sadique du fait de fixation aux stades precoces du conflit œdipien et de l’echec relatif de l’elaboration de la position depressive. Cette faille dans l’elaboration de cette position developpementale essentielle reactivee lors de l’adolescence renforce, dans une perspective kleinienne, le recours aux mecanismes de defense obsessionnel et maniaque qui demeurent insuffisamment efficients pour apaiser les angoisses de perte objectale et les angoisses paranoides sous-jacentes. Du point de vue de la relation d’objet interpersonnelle, l’accent est mis sur l’organisation en faux-self caracterisee par l’importance de la soumission au narcissisme de l’objet primaire au detriment de l’epanouissement du narcissisme du sujet. Les modalites de transaction parents–enfants vont dans le sens du verrouillage des sollicitudes affectives de l’enfant. Les gratifications orales et la regression qu’elles necessitent sont mal tolerees tandis que l’on note une valorisation du conformisme social, de la performance, de l’ascetisme et un surinvestissement de l’image du corps comme lieu de maitrise des affects et comme pivot identificatoire central. Enfin, du point de vue intraculturel de la relation d’objet, l’anorexie mentale est consideree comme un modele d’inconduite fourni par la societe et la culture permettant au sujet de colmater sa souffrance psychique. L’anorexie mentale pourrait constituer une veture symptomatique surdeterminee par les facteurs socioculturels, utilisee par l’adolescent pour tenter d’apaiser ses angoisses de separation et cicatriser ses angoisses schizoparanoides lors de la reactivation du processus de separation-individuation aux alentours de la periode de la puberte.

Objective Longitudinal studies have shown that alexithymic features can interfere with treatment response in eating disorders. However, an alternative hypothesis could be that clinicians faced with alexithymic patients chose different treatment options according to their perceptions of these patients. The aim of this investigation was to explore the relationships between alexithymic features and treatment options provided by professionals in a naturalistic prospective study of eating disorders. Methods We conducted a 3-year longitudinal study exploring a sample of 102 DSM-IV Eating Disorder patients with the Toronto Alexithymia Scale (TAS-20). All treatments received during follow-up were recorded and recoded dichotomously, and crossed with the variation of alexithymic categories (cut-off ≥ 56) between inclusion and follow-up. Results Patients received different treatments according to their alexithymic profile, in terms both of number and type of treatment received. Patients with high, stable levels of alexithymia received overall more treatments, and significantly more antidepressants, than non-alexithymic patients. Patients who became alexithymics during follow-up were more often rehospitalized and received fewer regular psychotherapies than the non-alexithymic patients. Conclusions Professionals should carefully monitor these personality features and be aware of the potential impact of alexithymic features on treatment compliance and on treatment choice for eating disordered patients.

This article complements the results in Guilbaud (Biometrical Journal 2008; 50:678-692). Simultaneous confidence regions were derived in that article that correspond to any given multiple testing procedure (MTP) in a fairly large class of consonant closed-testing procedures based on marginal p-values and weighted Bonferroni tests for intersection hypotheses. This class includes Holm's MTP, the fixed-sequence MTP, gatekeeping MTPs, fallback MTPs, multi-stage fallback MTPs, and recently proposed MTPs specified through a graphical representation and associated rejection algorithm. More general confidence regions are proposed in this article. These regions are such that for certain underlying MTPs which are not alpha-exhaustive, they lead to confidence assertions that may be sharper than rejection assertions for some rejected null hypotheses H when not all Hs are rejected, which is not the case with the previously proposed regions. In fact, various alternative confidence regions may be available for such an underlying MTP. These results are shown through an extension of the previous direct arguments (without invoking the partitioning principle), and under the same general setup; so for instance, estimated quantities and marginal confidence regions are not restricted to be of any particular kinds/dimensions. The relation with corresponding confidence regions of Strassburger and Bretz (Statistics in Medicine 2008; 27:4914-4927) is described. The results are illustrated with fallback and parallel-gatekeeping MTPs.

In this paper we describe Bonferroni-based multiple testing procedures (MTPs) as strategies to split and recycle test mass. Here, 'test mass' refers to (parts of) the nominal level alpha at which the family-wise error rate is controlled. Briefly, test mass is split between different null hypotheses, and whenever a null hypothesis is rejected, the part of alpha allocated to it may be recycled to the testing of other hypotheses. These recycling MTPs are closed testing procedures based on raw p-values associated with testing the individual null hypotheses, and the class of such MTPs includes, for example, serial and parallel gatekeeping, fallback and Holm procedures. Graphical displays and a concise algebraic notation are provided for such MTPs. This recycling approach has pedagogical advantages and may facilitate the tailoring of MTPs for different purposes.

Holm's (1979) step-down multiple-testing procedure (MTP) is appealing for its flexibility, transparency, and general validity, but the derivation of corresponding simultaneous confidence regions has remained an unsolved problem. This article provides such confidence regions. In fact, simultanenous confidence regions are provided for any MTP in the class of short-cut consonant closed-testing procedures based on marginal p -values and weighted Bonferroni tests for intersection hypotheses considered by Hommel, Bretz and Maurer (2007). In addition to Holm's MTP, this class includes the fixed-sequence MTP, recently proposed gatekeeping MTPs, and the fallback MTP. The simultaneous confidence regions are generally valid if underlying marginal p -values and corresponding marginal confidence regions (assumed to be available) are valid. The marginal confidence regions and estimated quantities are not assumed to be of any particular kinds/dimensions. Compared to the rejections made by the MTP for the family of null hypotheses H under consideration, the proposed confidence regions provide extra free information. In particular, with Holm's MTP, such extra information is provided: for all nonrejected H s, in case not all H s are rejected; or for certain (possibly all) H s, in case all H s are rejected. In case not all H s are rejected, no extra information is provided for rejected H s. This drawback seems however difficult to overcome. Illustrations concerning clinical studies are given. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

L’alexithymie est un neologisme cree par Sifneos en 1972 pour definir l’incapacite a exprimer ses emotions par des mots (a-privatif, lexi : mots ; thymie : emotions, humeur). De nombreuses etudes semblent attester d’un lien entre l’alexithymie et les troubles de l’empathie. En effet, des etudes cliniques ont retrouve chez certains sujets alexithymiques une limitation dans la reconnaissance des expressions faciales, une pauvrete de la mimique faciale lorsque ces sujets sont soumis a un etat de stress experimental, une difficulte a percevoir les emotions d’autrui avec un faible niveau de conscience emotionnel. De meme, l’alexithymie a ete retrouvee dans les syndromes d’Asperger, associee aux troubles de l’empathie. La difficulte a percevoir ses propres emotions devrait pour le moins etre referee a cette autre difficulte caracterisee par l’incapacite a percevoir les emotions d’autrui et plus generalement a se constituer une theorie des etats mentaux d’autrui. L’idee d’une parente ontogenique entre le mode de fonctionnement alexithymique et un mode de fonctionnement appartenant a un registre autistique du Moi merite d’etre soulevee. Dans une perspective metapsychologique, l’auteur developpe l’idee que l’alexithymie primaire et secondaire s’integreraient dans un continuum developpemental du normal au pathologique se referant a un dysfonctionnement precoce durant la phase d’autosensualite sur le modele topique de la fixation-regression. L’alexithymie primaire pourrait renvoyer a des troubles de l’empathie tandis que l’alexithymie secondaire renverrait a une strategie defensive visant a se proteger d’affects traumatiques. Du fait de fixations ou microfixations durant la phase d’autosensualite, des manœuvres de protection autistique auraient fait le lit assez precocement d’un fonctionnement alexithymique avec une certaine distorsion dans la capacite a reconnaitre ses sentiments et ceux d’autrui. L’alexithymie pourrait etre liee a un usage important et precoce de l’identification par demantelement generant un recours excessif au processus d’hallucination negative (endo- et extrapsychique) de secteurs de la vie emotionnelle qui ont ete soit forclos (alexithymie primaire) soit traumatiques et peu elabores (alexithymie secondaire). Ce mode de fonctionnement serait present chez tout individu de maniere residuelle et appartiendrait a un registre autistique du Moi. Mais c’est le recours exclusif a un fonctionnement alexithymique qui marquerait son caractere pathologique avec, en cas de debordements emotionnels non contenables en dernier recours par ces manœuvres de protection autistique, un risque de decompensation psychosomatique.

A step towards a successful implementation of timeresolved digital in-line holography with extreme ultraviolet radiation is presented. Ultrashort XUV pulses are produced as high-order harmonics of a femtosecond laser and a Schwarzschild objective is used to focus harmonic radiation at 38 nm and to produce a strongly divergent reference beam for holographic recording. Experimental holograms of thin wires are recorded and the objects reconstructed. Descriptions of the simulation and reconstruction theory and algorithms are also given. Spatial resolution of few hundreds of nm is potentially achievable, and micrometer resolution range is demonstrated., Comment: 8 pages, 8 figures

A plasma-based extreme ultraviolet (XUV) laser is experimentally characterized to have a record-short coherence time of ~500 femtoseconds, which paves the way to amplify weak high-harmonic-generation (HHG) radiation sources without losing their ultrashort, femtosecond characteristics.

Extreme ultra-violet (EUV) laboratory lasers can be used to probe energy transport in laser irradiated solid targets. We report on a recent experiment undertaken at LASERIX whereby the heating of laser-irradiated targets containing a thin layer of iron (50 nm) encased in plastic (CH) was diagnosed using EUV laser (13.9 nm) back-lighter probing. The heating laser pulse duration was 35fs with focal irradiances of \(3 \times 10^{16}\)Wcm\(^{-2}\) and a deliberate prepulse 20 ps before the main pulse at irradiances of \(3 \times 10^{15}\)Wcm\(^{-2}\). A one dimensional hydrodynamic fluid code HYADES has been used to simulate the temporal variation in EUV transmission using IMP opacity values for the iron layer and the simulated transmissions compared to measured transmission values. When a deliberate prepulse is used to preform an expanding plastic plasma, it is found that radiation heating is dominant in the heating of the iron layer giving rise to a rapid decrease in EUV opacity and an increase in the transmission of the 13.9nm laser radiation as the iron ionizes to Fe\(^{5+}\) and above.

International audience; We discuss the role of the spectral properties of XUV lasers in the amplification of femtosecond pulses in two different regimes. We present an overview of our recent spectral characterization of the four types of collisionally-pumped systems, also including other measurements from the literature. This is used to assess the potential of the different types of XUV lasers to amplify femtosecond pulses, either in the adiabatic or in the dynamic regime.

X-ray laser simulations based on Ehybrid code have shown that enhanced plasma x-ray laser emission can be achieved mastering the ionization dynamics and plasma temperature using one long and two short pulses (Ursescu and Ionel, J Optoelectron Adv Mat 12:48–51, 2010). In parallel, two simple methods to generate multiple short pulses for pumping x-ray lasers were reported in conjunction with x-ray laser developments. Five to ten fold enhancement in the emission of the silver x-ray laser was demonstrated using the newly developed pump methods, when compared with the traditional one, based on a long pulse followed by one short pump pulse. An overview of these recent experiments will be presented. The possible implementation of these novel x-ray laser pumping methods at Extreme Light Infrastructure—Nuclear Physics facility will be discussed.

Seeded operation of a Neon-like Titanium plasma-based soft x-ray laser is described. The plasma amplifier is pumped using a variation of the classical grazing incidence pumping technique, combining a long low energy pulse followed by a main short pulse. Because the preformed plasma is underionized, a part of the main short pulse energy is used to ionized it to the lasing stage. Consequences of this feature on seeded laser properties are discussed.

In very intense electromagnetic fields, the vacuum refractive index is expected to be modified due to nonlinear quantum electrodynamics (QED) properties. Several experimental tests using high intensity lasers have been proposed to observe electromagnetic nonlinearities in vacuum, such as the diffraction or the reflection of intense laser pulses. We propose a new approach which consists in observing the refraction, i.e. the rotation of the waveplanes of a probe laser pulse crossing a transverse vacuum index gradient. The latter is produced by the interaction of two very intense and ultra short laser pulses, used as pump pulses. At the maximum of the index gradient, the refraction angle of the probe pulse is estimated to be $0.2 \times (\frac{w_0}{10 \mathrm{\mu m}})^{-3} \times \frac{I}{1 \mathrm{J}}$~picoradians, where $I$ is the total energy of the two pump pulses and $w_0$ is the minimum waist (fwhm) at the interaction area. Assuming the most intense laser pulses attainable by the LASERIX facility ($I = 25$~J, 30~fs fwhm duration, 800~nm central wavelength) and assuming a minimum waist of $w=10 \mathrm{\mu m}$ (fwhm) (corresponding to an intensity of the order of $10^{21}$~W/cm$^2$), the expected maximum refraction angle is about 5~picoradians. An experimental setup, using a Sagnac interferometer, is proposed to perform this measurement., Comment: Accepted for publication in Eur. Phys. Journal D

We report the work done on a transient soft X-ray laser (SXRL) beam to deliver a proper extreme UV irradiation source for applications. The same optical tool was first demonstrated on a quasi stationnary state (QSS) soft X-Ray laser at the PALS Institute in Prague. The problem set by the transient soft X-Ray laser developed by the LIXAM at the LULI installation in Palaiseau is more crucial, first because the beam spatial profile is more irregular secondly because high repetition rate soft X-ray laser facilities in the future are based on this SXRL type. The spots obtained show a 20 micron average diameter and a rather homogeneous and smooth profile that make them a realistic irradiation source to interact with targets requiring relatively high fluence (near 1 J/cm2) or intensity (near 1011 W/cm2) in the extreme UV domain.

The spectral width of a Ni-like silver transient soft X-ray laser (4d-4p λ= 13.9 nm) was experimentally inferred from the measurement of its temporal coherence, performed with a novel wavefront division interferometer. The measured coherence time of 3 ps corresponds to a spectral linewidth of 0.7 mA which is narrow. We compare this experimental result to numerical simulations of the amplified line profile, performed along two different approaches. Both calculations predict a spectral linewidth that is about 3 times larger than the experimental value. We discuss several effects that might explain this discrepancy. We show that, due to the short duration of the X-ray laser pulse, the assumption of a stationary electromagnetic field used in both the experimental analysis and in the calculations need to be reconsidered.

Beam sections of transient collisional excitation (TCE) soft X-ray lasers exhibit highly contrasted intensity modulations forming complex patterns. We present model calculations that reproduce these experimental observations both qualitatively and quantitatively. The low spatial coherence, high longitudinal coherence and short pulse duration of the source are shown to control the visibility of the beam structures. Comparison with other types of laser-based soft X-ray lasers is discussed. We derive simple relationships that relate the spatial and temporal characteristics of the emitting source to the main features of the beam small-scale structures.

We have investigated a new scheme for laser plasma transient collisional soft x-ray lasers based on the use of an additional laser to produce the preplasma. Soft x-ray emission measurements made for different solid targets are presented and discussed. A significant enhancement of the SXRL emission as compared to double-pulse single-beam grazing incidence (DGRIP) using the same pump laser is reported for 13.9- and 32.6-nm SXRL wavelengths.

We report the preliminary result of the application of the collisional Ne-like soft x-ray laser as radiation source to induce DNA damage. The goal of this experiment was a test bed study of the damage yields induced by soft x-ray radiation in dried plasmid DNA sample. The saturated Ne-like soft x-ray laser available at the PALS facility, delivering several millijoules in a single 100 ps pulse at 21.2 nm was used to irradiate two different plasmids: pSPl 89 and pBS. The study is centered on the dose effect leading to single and double strand break in DNA.

In a multivariate framework, it is shown how the two treatments in a 2 × 2 crossover trial with multivariate response can be compared with respect to mean vectors, i.e. fixed treatment effects, as well as within-subject covariance matrices, marginally and simultaneously. No distributional assumption is made about the between-subject variability, whereas multivariate normality is assumed for the within-subject variability. The proposed exact statistical inferences are valid even with few subjects. Data from a crossover trial with bivariate response are analysed with the proposed multivariate methods as well as with univariate methods.

This article extends recent results [Scand. J. Statist. 28 (2001) 699] about exact non-parametric inferences based on order statistics with progressive type-II censoring. The extension lies in that non-parametric inferences are now covered where the dependence between involved order statistics cannot be circumvented. These inferences include: (a) tolerance intervals containing at least a specified proportion of the parent distribution, (b) prediction intervals containing at least a specified number of observations in a future sample, and (c) outer and/or inner confidence intervals for a quantile interval of the parent distribution. The inferences are valid for any parent distribution with continuous distribution function. The key result shows how the probability of an event involving k dependent order statistics that are observable/uncensored with progressive type-II censoring can be represented as a mixture with known weights of corresponding probabilities involving k dependent ordinary order statistics. Further applications/developments concerning exact Kolmogorov-type confidence regions are indicated.

The term “alexithymia” was coined by Sifneos. It is characterised by a lack of words to express emotion (a: absence of; lexi: words; thymia: emotions, affects). Its characteristics were suggested to occur more frequently in individuals with so-called “psychosomatic disorders”, but this is still a matter of controversy. Here we review the psychosomatic network of alexithymia, i.e. the immune and physiological correlates of alexithymia. Some studies suggest that inaccuracy in recognising emotional states, or the way of coping with negative emotions, may influence immune function. Alexithymia is associated with higher tonic baseline levels of sympathetic activity and lower sympathetic reactivity during acute stress. Few studies have reported a diminished immune-mediated cellular response in alexithymics with oversecretion of glucocorticoids. We hypothesise that alexithymic subjects may suffer from unnoticed chronic stress with physiological and endocrine and immune consequences. Alexithymia may skew the Th-1/Th-2 balance toward Th-2 dominant immunity and lower cell-mediated (Th-1) immune response and may increase an individual’s risk for stress-related disorder.

In some applications, microimaging in EUV requires a long working distance, i.e. a long distance between the object plane and the first optical surface. This is in particular the case when imaging hot plasmas, such as those produced by high energy pulsed lasers focused onto solid targets for X-ray laser production or plasma fusion studies. In this context, a working distance of several 10's cm is required, which makes even the usual Schwarzschild configurations not convenient. Other major requirements are a high resolution and phase detection capability, in order to allow a direct detection of the plasma density. The field should be millimetric. A system was build for diffraction limited (resolution 1 pm) interferometric imaging at λ=13.9 nM, using an X-ray laser source. This system was first tested on a synchrotron beamline (LURE, Orsay). Also, the imaging part was used to obtain high resolution images of the lasing emission provided by a Ni-like, picosecond Ag plasma, at λ=13.9 nm. Such a system might be useful in other applications, eg. phase-sensitive micro-inspection of reflecting surfaces in the field of EUV lithography.

Measurements of the duration of X-ray lasing pumped with picosecond pulses from the VULCAN optical laser are obtained using a streak camera with 700 fs temporal resolution. Combined with a temporal smearing due to the spectrometer employed, we have measured X-ray laser pulse durations for Ni-like silver at 13.9 nm with a total time resolution of 1.1 ps. For Ni-like silver, the X-ray laser output has a steep rise followed by an approximately exponential temporal decay with measured full-width at half-maximum (FWHM) of 3.7 (±0.5) ps. For Ne-like nickel lasing at 23.1 nm, the measured duration of lasing is ≈10.7 (±1) ps (FWHM). An estimate of the duration of the X-ray laser gain has been obtained by temporally resolving spectrally integrated continuum and resonance line emission. For Ni-like silver, this time of emission is ≈22 (±2) ps (FWHM), while for Ne-like nickel we measure ≈35 (±2) ps (FWHM). Assuming that these times of emission correspond to the gain duration, we show that a simple model consistently relates the gain durations to the measured durations of X-ray lasing.

Resume Le champ de la psycho-neuro-immunologie (PNI) repose sur la mise en evidence d’interrelations entre systeme nerveux central, systeme neuroendocrinien et immunitaire sensibles a des facteurs psychologiques et environnementaux. De nombreuses recherches attestent d’une communication bidirectionnelle entre systeme nerveux et immunitaire, soit directement, soit via une voie de regulation neuroendocrinienne. Differents modeles ont ete decrits, permettant de rendre compte des mecanismes physiopathologiques sous-jacents a la depression. On distingue les modeles neuroendocrinien et cytokinergique qui different quant a la place vouee a l’axe corticotrope et a la reponse immune. Neanmoins la confrontation avec les donnees de la litterature ne confirme pas toujours les modeles issus de la PNI. Les resultats des etudes sont souvent contradictoires, parmi ceux-ci, les plus souvent retrouves sont une augmentation des cytokines pro-inflammatoires qui pourraient interagir avec le systeme serotoninergique, une alteration de l’activite lymphocytaire chez les sujets deprimes âges et une activation de l’axe corticotrope. Les limites de la PNI sont en grande partie liees a la multitude et l’heterogeneite des parametres biologiques qui interviennent dans les boucles de regulations neuro-immunitaires, aux etapes limitantes de la psychiatrie biologique et a l’incapacite de pouvoir inferer a partir de prelevement peripherique de l’etat du systeme immunitaire.

Resume L’alexithymie est un terme invente par Sifneos qui se caracterise par l’absence de mots pour exprimer ses emotions (a : privatif ; lexi : mots ; thymie : emotions, humeur). Apres avoir passe en revue les differents modeles etiopathogeniques de l’alexithymie et les instruments psychometriques permettant de quantifier cette dimension, nous donnons les premiers resultats du reseau dependance concernant la prevalence de l’alexithymie chez des patients souffrant de conduites d’addictions (alcoolisme, toxicomanie, anorexie, boulimie) comparativement a une population temoin. Dans le cadre de cette etude multicentrique, 654 patients presentant des conduites de dependance selon le DSM-IV ont ete compares a 767 temoins apparies sur l’âge, le sexe et le niveau socioprofessionnel ; ces sujets avaient entre 15 et 50 ans. L’alexithymie fut evaluee par la Toronto Alexithymia Scale dans sa version a 20 items. La prevalence de l’alexithymie en population generale etait de 20,7 %. Ses relations avec les donnees sociodemographiques montrent que l’alexithymie dans notre population temoin n’etait pas correlee a l’âge, ni avec le sexe, ni avec le niveau socio-educatif. En revanche, les sujets appartenant aux couches sociales defavorisees s’averaient plus alexithymiques que les autres. A l’instar des donnees de la litterature, la prevalence de l’alexithymie etait significativement plus elevee dans le cadre des conduites de dependance (variant de 63 % chez les patients alcooliques a 41 % chez les patients toxicomanes) comparativement aux sujets temoins. Cette difference etait en grande partie liee a la composante emotionnelle de l’alexithymie et non a sa composante cognitive.

An alternative, novel multiple pulse generation scheme was implemented directly after the optical compressor output of an x-ray pump laser. The new method uses a polarization sensitive thin film beam splitter and a half-wavelength wave plate for tuning the energy ratio in the multiple short pulses. Based on this method, an extensive study was made of the running parameters for a grazing incidence pumped silver x-ray laser (XRL) pumped with a long pulse of 145 mJ in 6 ns at 532 nm and up to 1.45 J in few picoseconds at 810 nm. Fivefold enhancement in the emission of the silver XRL was demonstrated using the new pump method.

International audience; We present a refined measurement of the temporal coherence of the zinc X-ray laser generated at PALS, using a wavefront-division interferometer. The corresponding bandwidth of the lasing line is shown (i) to be broader than those of other types of X-ray lasers, previously characterized with the same instrument, and (ii) is compatible with the amplification of subpicosecond pulses. Similar measurements were also performed for shorter amplification lengths and the small-signal gain was carefully characterized.

We show that a significant enhancement of the photon flux produced by high harmonic generation can be obtained through guided configuration at high laser intensity largely above the saturation intensity. We identify two regimes. At low pressure, we observe an intense second plateau in the high harmonic spectrum in argon. At relatively high pressure, complex interplay between strongly time-dependent ionization processes and propagation effects leads to important spectral broadening without loss of spectral brightness. We show that the relevant parameter for this physical process is the product of laser peak power by gas pressure. We compare source performances with high harmonic generation using a gas jet in loose focusing geometry and conclude that the source developed is a good candidate for injection devices such as seeded soft x-ray lasers or free electron lasers in the soft x-ray range.

We have investigated the high harmonic generation driven by two quasi-collinear IR pulses separated by picosecond delay. Experiments were performed at the LASERIX facility using 50 fs pulses at 800 nm with energy up to 25 mJ. We have studied the generation of two high harmonic pulses from the same medium. In particular, we show how the ratio in energy of each pulse can be used to balance the perturbation induced by the first pulse in the generating gas.

EUV coherence measurement and control is a challenging task which has dramatically progressed in recent years, mainly motivated by the development of sources with novel properties and their applications Non-stationary fields are an important aspect of this domain, for which numerous theoretical tools are now available. SASE XFELs have not been treated extensively in this chapter, but these devises share many common theoretical and instrumental aspects with other sources. Recently, the principle of single shot measurements of temporal and spatial coherence has been investigated using LCLS X-ray free electron laser. This technique is based on the analysis of the large angle diffraction pattern from a scattering sample, which involves path differences corresponding to greater than the expected coherence time. This idea will also be of use for other sources, in order to analyse single shot field structures or to mitigate shot to shot fluctuations. In the visible range, static Fourier-transform Michelson interferometry using echelon mirrors is already operational, and an interesting development of this technique has been proposed by Chilla, Marconi and Rocca. In this device, gratings are not only used as beam splitters but they also contribute to the generation of pulses with tilted energy fronts. This enables a complete record of the temporal coherence function in a single image and potentially in a single shot. Finally, many concepts presented here are also relevant for determining field polarisation structures, but this is beyond the scope of this chapter.