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Free-electron lasers generate high-brilliance coherent radiation at wavelengths spanning from the infrared to the X-ray domains. The recent development of short-wavelength seeded free-electron lasers now allows for unprecedented levels of control on longitudinal coherence, opening new scientific avenues such as ultra-fast dynamics on complex systems and X-ray nonlinear optics. Although those devices rely on state-of-the-art large-scale accelerators, advancements on laser-plasma accelerators, which harness gigavolt-per-centimetre accelerating fields, showcase a promising technology as compact drivers for free-electron lasers. Using such footprint-reduced accelerators, exponential amplification of a shot-noise type of radiation in a self-amplified spontaneous emission configuration was recently achieved. However, employing this compact approach for the delivery of temporally coherent pulses in a controlled manner has remained a major challenge. Here we present the experimental demonstration of a laser-plasma accelerator-driven free-electron laser in a seeded configuration, where control over the radiation wavelength is accomplished. Furthermore, the appearance of interference fringes, resulting from the interaction between the phase-locked emitted radiation and the seed, confirms longitudinal coherence. Building on our scientific achievements, we anticipate a navigable pathway to extreme-ultraviolet wavelengths, paving the way towards smaller-scale free-electron lasers, unique tools for a multitude of applications in industry, laboratories and universities.

Microfossil classification is an important discipline in subsurface exploration, for both oil & gas and Carbon Capture and Storage (CCS). The abundance and distribution of species found in sedimentary rocks provide valuable information about the age and depositional environment. However, the analysis is difficult and time-consuming, as it is based on manual work by human experts. Attempts to automate this process face two key challenges: (1) the input data are very large - our dataset is projected to grow to 3 billion microfossils, and (2) there are not enough labeled data to use the standard procedure of training a deep learning classifier. We propose an efficient pipeline for processing and grouping fossils by genus, or even species, from microscope slides using self-supervised learning. First we show how to efficiently extract crops from whole slide images by adapting previously trained object detection algorithms. Second, we provide a comparison of a range of self-supervised learning methods to classify and identify microfossils from very few labels. We obtain excellent results with both convolutional neural networks and vision transformers fine-tuned by self-supervision. Our approach is fast and computationally light, providing a handy tool for geologists working with microfossils.

La pandémie de Coronavirus Disease 2019 (COVID-19) a émergé à Wuhan, en Chine. Causée par un virus, le SARS-CoV-2, cette dernière s’est répandue dans le monde en quelques semaines. Parallèlement à la gestion de la crise sanitaire sur le terrain, la communauté scientifique s’est penchée sur un moyen de l’enrayer. Des vaccins candidats à ARNm tels que Pfizer BNT162b2 et Moderna m-RNA-1273 ont donc été développés. Leur récente mise sur le marché soulève cependant des inquiétudes quant à leurs potentiels effets secondaires, parmi eux, le zona ophtalmique.

HUMAN BEINGS ARE COMPLEX CREATURES, shaped by a mixture of genetic code and learned behavior from their surrounding environment. The infinite combinations of physical characteristics and cultural teachings and experiences [...]

Not-for-profit hospitals are being forced to take a hard look at the justification of their tax-exempt status. They have faced high-profile challenges of their tax exemption from numerous quarters for [...]

A new preventative approach with water-based mud has been applied in several fields, while drilling through a series of highly depleted sands, and has proven to be effective in preventing [...]

To evaluate the effect of intrauterine administration of activated peripheral blood mononuclear cells (PBMC) on intrauterine insemination (IUI) success rates.

Toxic anterior segment syndrome (TASS) is a rare but serious complication of anterior segment surgery characterised by an acute sterile inflammation. The ICL implantation has gained popularity for the correction of moderate and high ametropias in cases where classical keratorefractive procedures are contraindicated.

The aromatic hydrocarbon receptor (AhR) had been described as a molecular sensor to which many environmental pollutants, such as polycyclic aromatic hydrocarbons (PAHs) and halogenated aromatic hydrocarbons (HAHs) binds leading to many biological and toxic effects. Recently, it had been demonstrated that the differentiation of CD4+T cells is influenced by AhR ligands present in the surrounding microenvironment of the cells. In this study, we assessed the immune environment of CD4+T cells in a cohort of firefighters, a group of individuals more exposed to AhR ligands. Our results showed that in firefighters, Th17 and Treg cells were increased compared to our control group. Also, the microenvironment presents an increase in cytokines promoting the differentiation of these cells in firefighters. The presence of a large number of AhR ligands in the firefighters' sera had been observed. Finally, in vitro treatments of CD4+T cells with AhR ligands (BaP and Kynurenine) had shown an ability to modulate Treg and Th17 cells' differentiation.

•La coexistence, en Europe, de multiples définitions et réglementations des nanomatériaux manufacturés (NM) ouvre des possibilités de contestations qui nuisent à la gestion des risques. Elle n’exclue pour autant pas la référence systématique à une échelle nanométrique étroite (1 à 100nm) fondée sur un consensus politique international faute de l’être sur le plan scientifique.•Des difficultés techniques persistent pour le développement d’une métrologie adaptée à la caractérisation des paramètres physicochimiques et à l’identification d’un nano-objet.•Le registre R-nano de déclaration annuelle obligatoire des substances à l’état nanoparticulaire fait état de plus de 400 000 tonnes de NM déployées sur le territoire national dans des secteurs très variés mais dont certains concentrent les quatre NM les plus fortement produits et importés : carbonate de calcium (CaCO3) ; noir de carbone ; dioxyde de silice (SiO2) et dioxyde de titane (TiO2).•Il est nécessaire de modifier et/ou d’adapter les méthodologies de caractérisation des dangers (éco)toxicologiques afin d’améliorer leur applicabilité et leur fiabilité à des fins d’évaluation des risques sanitaires et environnementaux liés à ces substances.•Des méthodes permettent désormais d’identifier des sources d’exposition et d’évaluer l’exposition potentielle d’un opérateur. Il reste à développer une mesure quantitative pour l’exposition aux NM.•Le cadre juridique existant impose une maîtrise des risques liés aux NM. Toutefois, l’effectivité et l’interprétation des dispositions réglementaires appellent des clarifications sur les définitions utilisables ainsi que des développements techniques.•La limitation des expositions professionnelles s’impose face aux incertitudes relatives aux effets sur la santé humaine des NM, avec instauration de procédures de prévention tout au long du cycle de vie des produits.•Des recommandations ont été énoncées en juin 2018 par le Haut Conseil de Santé Publique (HCSP) pour la protection des travailleurs exposés au TiO2 nanométrique.•Le dispositif national EpiNano seul système national de surveillance et d’alerte sanitaire dédié à la surveillance épidémiologique des travailleurs potentiellement exposés aux NM, unique en France, présente une démarche anticipatrice de veille sanitaire.

We report a full experimental comparison study on the injection of a Ti:Sa multi-terawatt amplifier chain with a standard 15 fs Ti:Sa oscillator and 35 fs frequency-doubled fiber oscillator. The study highlights that the Ti:Sa oscillator, with high performance in terms of pulse duration and spectral width, can be replaced by the frequency-doubled fiber oscillator to seed Ti:Sa amplifier chains almost without any compromise on the output pulse duration and picosecond contrast. Finally, we demonstrate for the first time to our knowledge a 30 TW and 33 fs Ti:Sa amplifier injected by a fiber oscillator.

Pour disposer en de nombreux endroits des cotes maximales de crues et ce à moindre coût, l'implantation d'échelles à maxima s'avère très utile. Après avoir passé en revue les principaux types d'échelles à maxima rencontrés dans la littérature, nous détaillons le système développé en Nouvelle-Calédonie, appelé CalédoMax. Ce système s'avère être largement original principalement dans sa manière de mesurer et mémoriser la hauteur maximale atteinte durant la crue. Il est constitué de deux cordes rugueuses tendues sur lesquelles coulisse un flotteur qui pousse une bague montée sur l'une des cordes. Lors de la montée des eaux, le déplacement du flotteur vers le haut pousse la bague vers le haut. Celle-ci restant en position maximale lors de la décrue puisque prise en tenaille entre les deux cordes, elle permet d'approcher le niveau maximum atteint par la crue. Ensuite, les principales utilisations des échelles à maxima passées en revue, nous mettons en avant celles que nous privilégions en Nouvelle-Calédonie et qui concernent l'hydrométrie. Puis nous établissons un retour d'expérience de l'utilisation de notre réseau de CalédoMax qui, depuis 1988 a pu compter jusqu'à plus de 900 appareils et qui a permis de réaliser plus de 16400 mesures. Enfin, nous présentons notre méthode de stockage et de gestion des informations ainsi collectées, avant de conclure sur les possibilités de répliquer le CalédoMax dans d'autres contextes ainsi que les améliorations qui pourraient être envisagées.

Since 2012, the Peruvian government launched a National School Food Program. From doctoral research, this presentation demonstrates that two neighboring indigenous groups in the Peruvian Amazon, the Maijuna and the Napuruna, distinctly accept the school food. It examines the cultural differences of sensory perceptions, in particular sweetness and bitterness, in order to understand modalities of school food acceptance. The investigation is based on a 12-month ethnographic study carried out from 2013 to 2017. Ethnographic methods include fieldwork in local families, “participant observation” and semi-structured interviews focused on school food reception and sensory perceptions. The comparison of the vocabulary used to describe sweetness and bitterness, and the cultural representations related, reveals that both groups accept sweet milk porridge since it corresponds with the taste, texture, color they associate with their daily drink: the manioc beer. However, it appears that the Napuruna, unlike the Maijuna, thoroughly limit their children ‘s consumption of sweet food because they consider sweetness as a factor of laziness. In their educational model, they foster strength and hard-working by ingesting bitter substances. In contrast, the Maijuna value the porridge because they relate it to children's diet and more generally to edible food. They carefully avoid bitter food since they link it to poison, an association manifested in the use of the same term to qualify bitterness and poison.

This work investigates solar events occurred in September 2017 characterized by a series of Forbush decreases and a ground level enhancement (GLE). Forbush decreases is a rapid decrease in the observed https://en.wikipedia.org/wiki/Galactic_cosmic_rayintensity following a coronal mass ejection while GLE is induced by a strong solar event for which the flux of high‐energy solar particles is sufficient to enhance the radiation level on the ground. These investigations were performed using data recorded by a neutron spectrometer network composed of a Bonner sphere system. Two instruments located at Pic‐du‐Midi Observatory (+2,885 m above sea level) and at Concordia station (Antarctica, +3,233 m) record simultaneously and continuously the neutron spectra, allowing to consider short‐term variations during solar events. The main objective is to analyze neutron spectral properties including their energy distributions and dynamics. This paper presents cosmic ray‐induced neutron spectra during active solar event leading to changes in the local cosmic ray spectrum (Forbush decreases and a GLE). Concerning the GLE, analyses show that neutrons in the evaporation domain are particularly amplified during the GLE, while other energetic domains increase uniformly. This paper presents an analysis of neutron spectrum variations during solar event of September 2017Investigations are based on data recorded by a neutron spectrometer network (midlatitude and Antarctica stations)The peak of evaporation is particularly amplified during the GLE

Les masses rétropéritonéales regroupent un ensemble de tumeurs très diverses comportant les tumeurs d’organe (reins, voies excrétrices et surrénales), les tumeurs rétropéritonéales primitives et secondaires. Les tumeurs rétropéritonéales primitives sont des tumeurs rares, le plus souvent malignes et de diagnostic tardif. Elles sont représentées pour plus de la moitié d’entre elles par des sarcomes. Leur rareté associée à une grande variété explique les difficultés diagnostiques. L’objectif de cet article est de répertorier les caractéristiques d’imagerie présentes sur le scanner et l’IRM permettant de proposer des hypothèses diagnostiques. En cas de suspicion de sarcome, il est recommandé avant toute prise en charge thérapeutique de se référer à un centre expert permettant une approche multidisciplinaire (pathologiste, radiologue, chirurgien et oncologue) et de pratiquer une analyse histologique par biopsie percutanée radioguidée par voie rétropéritonéale.

The aim of this paper is to study the transport of nitrous oxide (N2O) from the Asian surface to the eastern Mediterranean Basin (MB). We used measurements from the spectrometer Thermal and Near infrared Sensor for carbon Observation Fourier transform spectrometer on board the Greenhouse gases Observing SATellite (GOSAT) over the period of 2010–2013. We also used the outputs from the chemical transport model LMDz‐OR‐INCA over the same period. By comparing GOSAT upper tropospheric retrievals to aircraft measurements from the High‐performance Instrumented Airborne Platform for Environmental Research Pole‐to‐Pole Observations, we calculated a GOSAT High‐performance Instrumented Airborne Platform for Environmental Research standard deviation (SD error) of ~2.0 ppbv for a single pixel and a mean bias of approximately −1.3 ppbv (approximately −0.4%). This SD error is reduced to ~0.1 ppbv when we average the pixels regionally and monthly over the MB. The use of nitrogen fertilizer coupled with high soil humidity during the summer Asian monsoon produces high N2O emissions, which are transported from Asian surfaces to the eastern MB. This summertime enrichment over the eastern MB produces a maximum in the difference between the eastern and the western MB upper tropospheric N2O (east‐west difference) in July in both the measurements and the model. N2O over the eastern MB can therefore be considered as a footprint of Asian summertime emissions. However, the peak‐to‐peak amplitude of the east‐west difference observed by GOSAT (~1.4 ± 0.3 ppbv) is larger than that calculated by LMDz‐OR‐INCA (~0.8 ppbv). This is due to an underestimation of N2O emissions in the model and to a relatively coarse spatial resolution of the model that tends to underestimate the N2O accumulation into the Asian monsoon anticyclone. Consistency between GOSAT N2O measurements and LMDz‐OR‐INCA model N2O resultsEvidence of a link between summertime Asian N2O Emissions and the Mediterranean tropospheric N2O

Proposer une méthode opérationnelle pour identifier les travailleurs potentiellement exposés aux nano-objets manufacturés, leurs agrégats et agglomérats (NOAA) et caractériser leur exposition potentielle dans le dispositif de surveillance épidémiologique EpiNano.

This paper presents a method to segment airplane radar tracks in high density terminal areas where the air traffic follows trajectories with several changes in heading, speed and altitude. The radar tracks are modelled with different types of segments, straight lines, cubic spline function and shape preserving cubic function. The longitudinal, lateral and vertical deviations are calculated for terminal manoeuvring area scenarios. The most promising model of the radar tracks resulted from a mixed interpolation using straight lines for linear segments and spline cubic functions for curved segments. A sensitivity analysis is used to optimise the size of the window for the segmentation process.

Mapmaking has become widespread through the Internet, resulting in a wide range of cartographic quality. To achieve better quality, mapmaking needs tools and online services for intuitive and efficient on-demand mapping. A project team at IGN, the French National Mapping Agency, is working on producing a digital cartographic model (DCM) from various existing databases and maps on which such tools and services are based. This DCM ranges from detailed topographic maps to small general road maps. GeoServer Web Map Service capabilities were used extensively to produce quality maps with various legends. Special care was taken to make a default legend suitable for customer data overlays, both on-screen and on paper. Web-based interface prototypes were built to guide users in choosing colors and creating their own original map legends. Users can also rely on a growing catalog of harmonious color palettes and map samples as sources of inspiration.

One of the main advantages of Nd-YAG lasers compared to CO2lasers consists of easy beam handling using optical silica fibers. However, up to now Nd-YAG applications for material processing were limited due to a rather low available mean output power (less than about 500 W). A Eureka project (termed "EU-226") which consequently aimed at developing the so called "High Power Solid State Laser (HPSSL)" capable of 1 to 3 kW, involved absorptivity studies results of which are given in this contribution. Metallic surfaces exhibit a higher absorptivity at 1.06 µm (Nd-YAG) than at 10.6 µm which improves the energy transfer with a Nd-YAG laser and decreases the thermal runaway. This was acertained by measurements of absorptivity as a function of temperature and by thermal cycle calculations. This permits laser surface hardening of steels without any coating or gas shielding, which prevents in particular pollution. Various materials, I. e. pure nickel, Inconel 718 and AISI 1045 steel, were studied, featuring in particular the influence of surface roughness, oxidation and initial absorptivity on laser-material interaction.

L’objectif de cet article est de rappeler pourquoi et comment le dépistage de masse organisé du cancer du sein s’est développé puis généralisé en France en 2004, et d’expliquer ce qu’est le classement BI-RADS de l’ACR. Des perspectives sur le futur du dépistage seront données.

Le but de cet article est de décrire les caractéristiques morphologiques des principales tumeurs digestives, de montrer l’intérêt de l’injection intraveineuse de produit de contraste et du balisage intestinal. Quelques rappels sur les aires ganglionnaires et l’anatomie du péritoine seront faits.

Présentation de trois cas cliniques qui illustrent la prise en charge actuelle pluridisciplinaire du cancer du col utérin, de l’endomètre et de l’ovaire.

L’IRM pelvienne permet une analyse morphologique plus fine de l’utérus (col et corps) et des ovaires par rapport au scanner que ce soit sans ou avec injection. Elle permet de faire un bilan d’extension locorégional et à distance, des cancers utérins, influençant ainsi la prise en charge. Elle évalue la réponse tumorale sous traitement, détecte les récidives locales ou à distance. Elle permet une meilleure caractérisation des lésions ovariennes.

In order to minimize thermal load to the workpiece pico- and femtosecond lasers gain an increasing market share in industrial applications such as surface structuring or thin film selective ablation. Due to nonlinear absorption they are capable to process any type of material (dielectrics, semiconductors, metals) and provide an outstanding quality suppressing heat affects on the workpiece. In this paper, we report on results about surface engraving of metals (Al, Cu, Mo, Ni), semiconductor (Si) and polymer (PC) using a picosecond thin disk Yb:YAG-amplifier, which could be used in the picosecond regime as well as in the femtosecond regime by simply changing the seed laser source. In the picosecond regime the oscillator pulses, ranging from 10 to 34ps, can be directly amplified which leads to a quite simple and efficient amplifier architecture. On the other hand, a broadband femtosecond oscillator and a CPA configuration can be used in order to obtain pulse duration down to 900fs. We compare these results to recently obtained achievements using commercial femtosecond lasers based on Yb-doped crystals and fibers and operating at comparable output power levels, up to 15Watt. Finally, we have considered etch rate and process efficiency for both ps- and fs-regimes as a function of average power, of fluence and of intensity.

We present an Yb-CALGO thin-disk laser in continuous regime. In a slightly multimode configuration we obtain up to 29.5W of average power, corresponding to a slope efficiency of 40% and an optical-to-optical efficiency of 32%. We then design a monomode cavity, and achieve 25W of average power. The tuning range of the laser emission was from 1018 to 1052nm. In a Q-switch regime, we obtain more than 1 mJ at 100 Hz repetition rate, and 4.5W at 10 kHz repetition rate.

We demonstrated a compact femtosecond laser producing 1mJ pulse energy and more than 30 W average power using the amplification of a broadband femtosecond oscillator in an Yb:YAG thin disk regenerative amplifier in a compact CPA configuration. The pulse duration slightly decreases with energy down to a value of 790 fs still keeping the amplified spectral width <3 nm and thus suitable for efficient second harmonic generation. This source answers to the need for high power, high energy and reliable femtosecond sources notably in the field of innovative precision micromachining and high repetition rate OPA/OPCPA pumping.

The high altitudes and extremely low temperatures of the Antarctic plateau result in an exceedingly low atmospheric water vapor content. In this article we estimate the precipitable water vapor at Dome A using optical spectra of the diffuse solar irradiance in the zenith direction. The spectra were obtained from the Nigel spectrometer at Dome A during 2009. We find that the Nigel spectra contain sufficient information to extract daily average water vapor estimates, which agree with satellite observations to within ± 0.22 mm. Finally, we use these water vapor estimates to model the optical and near-IR transmission (between 700 nm and 2.5 ?m) of Dome A to demonstrate significant advantages gained in this wavelength range and compare it with that of Paranal and Chajnantor, two midlatitude observatories.

Cryogenic cooling is a very interesting and promising apparatus for high power lasers, especially with Yb-doped materials. In fact, it is now well known that operating this type of laser materials at cryogenic temperatures such as 77K (liquid nitrogen temperature) positively affects their performance, especially at high power levels, because of increased thermal conductivities and absorption and emission cross sections. We present a high-power diode-pumped Yb:CaF2laser operating at cryogenic temperature (77 K). A laser output power of 97 W at 1034 nm was extracted for a pump power of 245 W. The corresponding global extraction efficiency (versus absorbed pump power) is 65%. The laser small signal gain was found equal to 3.1. The laser wavelength could be tuned between 990 and 1052 nm with peaks which well correspond to the structure of the gain cross section spectra registered at low temperature.

Many industrial and scientific applications need ultra-short and energetic pulses. Diode-pumped systems based on ytterbium-doped crystals have a huge interest thanks to their good thermal and spectroscopic properties. Among them, Yb:CaF2, shows very promising results for short pulse generation, and its long fluorescence lifetime, 2.4 ms, indicates a high energy storage capacity. We present a diode-pumped regenerative amplifier based on an Yb:CaF2crystal optimized to produce short pulses for various repetition rates ranging from 100 Hz to 10 kHz. The experiment is performed with a 2.6-% Yb doped 5-mm-long CaF2crystal grown by using the Bridgman technique and used at Brewster angle. To optimize the injection pulse spectrum in terms of bandwidth and maximum gain, the seed pulses are generated by a broadband Yb:CALGO oscillator centered at 1043 nm with a FWHM bandwidth of 15 nm at a repetition rate of 27 MHz. The pulses are then stretched to 260 ps with a transmission grating. The shortest pulse duration generated is 178-fs, and the corresponding energy is 1.4 mJ before compression (620 J after), at a repetition rate of 500 Hz for 16 W of pump power. The bandwidth is 10 nm centered at 1040 nm. At 10 kHz repetition rate, 1.4 W of average power before compression is obtained, corresponding to an optical-optical efficiency of 10%. We also noticed that the pulse duration tends to increase above 1 kHz, reaching 400 fs at 10 kHz.

AbstractWe report on the generation and delivery of 10.2 PW peak power laser pulses, using the High Power Laser System at the Extreme Laser Infrastructure – Nuclear Physics facility. In this work we demonstrate for the first time, to the best of our knowledge, the compression and propagation of full energy, full aperture, laser pulses that reach a power level of more than 10 PW.

Myostatin is a negative regulator of muscle mass. Important advances in our understanding of thecomplex biology of this factor have revealed the therapeutic potential of antagonizing the myostatin pathway. Herewe present the rationale for evaluating anti-myostatin therapies in human muscle-wasting disorders.

Genetic pleiotropy, the ability of a mutation in a single gene to give rise to multiple phenotypic outcomes, constitutes an important but incompletely understood biological phenomenon. We used a high-resolution and high-precision phenotypic profiling approach to quantify the fitness contribution of genes on the five smallest yeast chromosomes during different forms of environmental stress, selected to probe a wide diversity of physiological features. We found that the extent of pleiotropy is much higher than previously claimed; 17% of the yeast genes were pleiotropic whereof one-fifth were hyper-pleiotropic. Pleiotropic genes preferentially participate in functions related to determination of protein fate, cell growth and morphogenesis, signal transduction and transcription. Contrary to what has earlier been proposed we did not find experimental evidence for slower evolutionary rate of pleiotropic genes/proteins. We also refute the existence of phenotypic islands along chromosomes but report on a remarkable loss both of pleiotropy and of phenotypic penetrance towards chromosomal ends. Thus, the here reported features of pleiotropy both have implications on our understanding of evolutionary processes as well as the mechanisms underlying disease.Genetic pleiotropy, the ability of a mutation in a single gene to give rise to multiple phenotypic outcomes, constitutes an important but incompletely understood biological phenomenon. We used a high-resolution and high-precision phenotypic profiling approach to quantify the fitness contribution of genes on the five smallest yeast chromosomes during different forms of environmental stress, selected to probe a wide diversity of physiological features. We found that the extent of pleiotropy is much higher than previously claimed; 17% of the yeast genes were pleiotropic whereof one-fifth were hyper-pleiotropic. Pleiotropic genes preferentially participate in functions related to determination of protein fate, cell growth and morphogenesis, signal transduction and transcription. Contrary to what has earlier been proposed we did not find experimental evidence for slower evolutionary rate of pleiotropic genes/proteins. We also refute the existence of phenotypic islands along chromosomes but report on a remarkable loss both of pleiotropy and of phenotypic penetrance towards chromosomal ends. Thus, the here reported features of pleiotropy both have implications on our understanding of evolutionary processes as well as the mechanisms underlying disease.

The true global sourceof the farfield sound radiated from a subsonic jet is the entire dynamic found within the confines of the hydrodynamic field, a dynamic which comprises an unsteady compressive excitation of the medium resulting from turbulent mixing and unsteady temperature fluctuations, these being driven by a wide range of turbulence scales. Improved understanding, and subsequent modelling of the space-time character of the global source term has been acheived in the past through study of the different physical mechanisms implicated in its dynamic. The phenomena which have to date been accepted as important in terms of the radiated sound are (i) turbulent mixing and shear, (ii) fluctuating entropy, (iii) convective amplification and (iv) refraction and scattering of sound by the mean and turbulent components of the velocity field. Once identified as important, specific modelling strategies can and have been developed in order to deal with these phenomena. The existence of coherent structures in turbulent jets was identified as important in the 1970's and their role in the production of sound has received considerable attention in more recent years. However, direct identification of the causal link between this component of the turbulence and its sound field is a delicate matter due to the virtual impossibility of directly measuring the source dynamic of the flow, this being due to an overwhelming dominance of hydrodynamic energy in the source region, and a total absence of any hydrodynamic signature in the linear, acoustic region. As a result, modelling strategies where this component of the source term is concerned have remained, at best, highly empirical.An interesting region of the flow where our understanding of the relationship between the hydrodynamic causeand its acoustic effectis concerned is the near pressure field, found just outside the rotational region of the flow. In this region the signature of the sound production mechanism and its resultant sound field are both present, coincident in space and in time.This means that pressure measurements can here be used to study the space-time structure of the two with a view to discerning the causal relationship which links them. In this work, measurements performed in the near pressure field of an isothermal subsonic jet reveal a strong interaction mechanism between the reactive and propagating components of the pressure field associated with the coherent structures of the flow, the essential features of which are captured by a simple model. On account of the success of the model it is possible to draw a number of interesting conclusions concerning the sound production mechanism associated with these structures, the most important of these being that despite the rotational velocity field in which they exist, where their sound production is concerned they can be considered as a quasi-irrotational, or wavy-wall type source mechanism. The same observation in supersonic jets has led to considerable simplifications where noise prediction is concerned – instability wave models being thus appropriate. The results from this work illustrate how similar models may be appropriate for modelling the noise production by this component of the source mechanism, believed to be predominant where peak radiation is concerned.

The investigation of the Martian atmosphere is of key importance for an understanding of the planets present and past. Passive limb observations of thermal radiation at submillimeter wavelengths in the 320–350-GHz range by use of a state-of-the-art satellite receiver on a low Mars orbit allow important parameters such as the mixing ratios of H_2O, HDO, ^12CO, ^13CO, O_3, and H_2O_2 as well as the thermal profile to be retrieved with high precision and unprecedented vertical range and resolution, providing valuable information for better understanding of the planet’s water cycle, atmospheric dynamics, and photochemistry. The feasibility of these kinds of measurement is demonstrated by means of model simulations based on realistic atmospheric, spectroscopic, and instrumental parameters. Temperature can be retrieved to ∼90 km with half-scale height vertical resolution from single-scan measurements of emission lines of the long-lived species ^12CO and ^13CO. The global water-vapor distribution can be measured even under dry or wet conditions with good vertical resolution from the surface to ∼45 km, and simultaneous observations of HDO allow useful information on the D/H ratio up to an altitude of ∼30 km to be derived. The sensitivity of the limb-sounding technique also permits information on the photochemically important minor species O_3 and H_2O_2 to be obtained. It is shown that spectral averaging may improve precision, altitude range, and resolution of the retrieved profiles. Other frequency bands are explored, and the 435–465-GHz range is suggested as a possible alternative to the 320–350-GHz range.

Seventeen adult subjects participated in a multicentre trial to compare the performance between an NRT‐based MAP and their behavioural MAP. The NRT‐based MAP was made using a correction factor to predict T/C levels, calculated from the difference between the ECAP threshold (‘T‐NRT’) and the measured T/C levels at electrode 10, as described by Brown et al. (2000). A secondary aim was to compare T/C levels in behavioural MAPs at different stimulation rates with the predicted T/C levels in NRT‐based MAPs. Performance with both MAPs was evaluated using CNC words and sentences. Variations in the T/C levels between all MAPs were found, although results of the speech discrimination tests demonstrated no statistically significant difference between behavioural and NRT‐based MAPs. Copyright © 2003 Whurr Publishers Ltd.

Abstract: The interpersonal conflict gives an opportunity to learn living together and to accept differences. We consider the interpersonal conflict resolution strategies as an indicator of the socialization and as such of the autonomisation and social integration. If, at the earliest age, the child has the advantage of a differentiated and early paternal involvement, he would use a larger variety of adjustment mechanisms when he will be in conflitual situations. Indeed, the father facilitates and stimulates the subjectivation process which integrates the appearing premises of self-consciousness, around 3–4 year old, in the conducts of initiative and self affirmation; the father introduces and consolidates the process which integrates the opening to wider interpersonal relations, which notably appears in collaboration conducts and more especially resolution interpersonal conflict. In order to evidence the paternal influence on resolution strategies of interpersonal conflicts, we will develop some results of a comparative study conducted among girls and boys (aged from 3 to 5), and theirs fathers. We have thus determined some paternal configuration — established after questionnaire analyse — and conflict resolution strategies — coming from the statistical treatment of data from observations of free and organized-play situations, and from semi-directives interviews of the children.

EMCOR is a heterodyne receiver for the frequency range of 201 to 210 GHz. It has been designed for ground-based measurements of various minor constituents of the stratosphere involved in ozone chemistry. Since the aim was the detection of faint spectral lines, a superconducting tunnel junction has been chosen as mixer element and special care has been taken in developing the calibration unit of the system. The front-end is completed by a quasi-optical system, a solid state local oscillator with electronic tuning and a HEMT pre-amplifier. In the back-end an acousto-optical spectrometer is employed to analyse the signal. A PC controls the whole system. The instrument has been installed at a high mountain site in the Swiss Alps.

Some dynamic contact problems with friction can be formulated as an implicit variational inequality. A time discretization of such an inequality is given here, thus giving rise to a so‐called incremental solution. The convergence of the incremental solution is established, and then the limit is shown to be the unique solution of the variational inequality. This paper contains therefore not only some new results concerning the numerical aspect of some models of contact and friction but also a constructive existence result. Copyright © 2001 John Wiley & Sons, Ltd.