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Frequency-domain full-waveform inversion (FWI) is potentially amenable to efficient processing of full-azimuth long-offset stationary-recording seabed acquisition carried out with a sparse layout of ocean-bottom nodes (OBNs) and broadband sources because the inversion can be performed with a few discrete frequencies. However, computing the solution of the forward (boundary-value) problem efficiently in the frequency domain with linear algebra solvers remains a challenge for large computational domains involving tens to hundreds of millions of parameters. We illustrate the feasibility of 3D frequency-domain FWI with a subset of the 2015/2016 Gorgon OBN data set in the North West Shelf, Australia. We solve the forward problem with the massively parallel multifrontal direct solver MUMPS, which includes four key features to reach high computational efficiency: an efficient parallelism combining message-passing interface and multithreading, block low-rank compression, mixed-precision arithmetic, and efficient processing of sparse sources. The Gorgon subdata set involves 650 OBNs that are processed as reciprocal sources and 400,000 sources. Monoparameter FWI for vertical wavespeed is performed in the viscoacoustic vertically transverse isotropic approximation with a classical frequency continuation approach proceeding from a starting frequency of 1.7 Hz to a final frequency of 13 Hz. The target covers an area ranging from 260 km2 (frequency ≥ 8.5 Hz) to 705 km2 (frequency ≤ 8.5 Hz) for a maximum depth of 8 km. Compared to the starting model, FWI dramatically improves the reconstruction of the bounding faults of the Gorgon horst at reservoir depths as well as several intrahorst faults and several horizons of the Mungaroo Formation down to a depth of 7 km. Seismic modeling reveals a good kinematic agreement between recorded and simulated data, but amplitude mismatches between the recorded and simulated reflection from the reservoir suggest elastic effects. Therefore, future works involve multiparameter reconstruction for density and attenuation before considering elastic FWI from hydrophone and geophone data.

For the past century, scientists have debated whether or not ageing is directly selected by evolution. Because ageing occurs, by definition, late in life - that is, after the organism’s development is complete - many people believe that it cannot be actively selected for as a process. Furthermore, because it reduces an individual’s fitness, it is thought unlikely to be selected for. In agreement with this viewpoint, numerous theories have been proposed in the last 75 years to explain the observation of its widespread presence in the realm of life. The bd model of ageing is based on a simple life-history trait model that we recently introduced.Our model suggests that senescence can be positively selected through evolution due to the increased evolvability it confers on organisms, not through a specific mechanism but through a ‘function ageing’, limiting organismal maintenance and reproduction. It confirms the substrate for mutation accumulation and antagonistic pleiotropy theories while providing an elegant explanation for the apparent tradeoff between longevity and fertility that led to the disposable soma theory without requiring an energy tradeoff. Furthermore, it predicts that the Lansing effect will be present in organisms that exhibit rapid post-reproductive senescence. This formal and numerical modeling of the evolution of ageing also provides new hints for testing the validity of existing theories.

New Caledonia is among Earth's biodiversity hotspots, and we are far from knowing how many species it sustains. We applied DNA-based methods for quick biodiversity assessment of New Caledonian Arsipoda flea beetles, enhancing the discovery and description of new species. Mitochondrial DNA phylogenetic analysis (cox1, rrnS) for four out of five known neocaledonian taxa hints at the existence of additional species, and two are confirmed and described based on morphology: Arsipoda geographica Gómez-Zurita sp. nov. and Arsipoda rostrata Gómez-Zurita sp. nov. Timing this small radiation using standard insect mitochondrial substitution rates places its origin in the Miocene. A DNA-based approach to investigate potential food plants for these herbivorous insects reveals associations with Myrsinaceae and Ericaceae, which have not yet been found in New Caledonia, suggesting that this indirect methodology may help in discovering undetected flora. Traditional taxonomy and molecular approaches cooperate here, boosting our knowledge on species inventory and ecological interactions where it is most needed. © 2010 Taylor & Francis., This project was funded by a Research Grant (no. 8380-07) of the Committee of Research and Exploration of the National Geographic Society, and also benefited from a travel grant from the Percy Sladen Memorial Fund of the Linnean Society of London.

Cet article aborde successivement les progres effectues en matiere d'environnement, et en matiere de radioprotection. Sur le premier point, dont le champ est large, elle se limite aux rejets et dechets radioactifs.

The early stages of passivation in high temperature water of a nickel–chromium–iron alloy (Alloy 600) have been investigated by X-ray Photoelectron Spectroscopy (XPS) and Scanning Tunneling Microscopy (STM). The samples (polycrystal Ni−16Cr−9Fe (wt. %) and single crystal Ni−17Cr−7Fe (1 1 1)) have been exposed for short time periods (0.4–8.2 min) to high temperature (325 °C) and high pressure water, under controlled hydrogen pressure, in a microautoclave designed to transfer the samples from and to the XPS spectrometer without air exposure. In the early stages of oxidation of the alloy (0.4–4 min), an ultra-thin oxide layer (about 1 nm) is formed, which consists of chromium oxide (Cr2O3), according to the Cr 2p3/2 core level spectrum. An outer layer of Cr(OH)3 with a very small amount of Ni(OH)2 is also revealed by the Cr 2p3/2, Ni 2p3/2, and O 1s core level spectra. At this early stage, there is a temporary blocking of the growth of Cr2O3. For longer exposures (4–8 min), the Cr2O3 inner layer becomes thicker, at the expense of the outer Cr(OH)3 layer. This implies the transport of Cr and Ni through the oxide layer, and release of Ni2+ in the solution. The structure of the ultra-thin oxide film formed on a single crystal Ni−17Cr−7Fe(1 1 1) alloy was analysed by STM in the constant current mode; STM images reveal that, in the early stages of oxidation, the oxide is crystalline, and the observed structure is consistent with the hexagonal structure of the oxygen sub-lattice in the basal plane (0 0 0 1) of α-Cr2O3.

In the present work, the effect of milk protein hydrolysates on probiotic cell counts and acidification in fermented milks was studied. Two strains of probiotic bacteria, Lactobacillus acidophilus LA-5 and Lactobacillus rhamnosus LR-35, were used in mixed culture with Streptococcus thermophilus ST-7. The effect of three casein hydrolysates and three whey protein hydrolysates were investigated by adding them to milk at a concentration ranging from 0.25 to 4 g L −1 . Addition of hydrolysate enhanced the growth of S. thermophilus and acidification, thus reducing the fermentation time, and growth of probiotic bacteria. On the other hand, survival of probiotic bacteria was improved when milk was added with hydrolysate. As a consequence, the addition of hydrolysate had a differential action on probiotic cell counts in fermented milks after storage, depending on the balance between its negative effect on growth of probiotic bacteria and its positive effect on the survival of probiotic bacteria.

The aim of this work is to characterize the oxidation behaviour of different nickel-base alloys exposed to high-temperature and high-pressure water for short oxidation times. The behaviour of Alloy 600 (74% Ni, 16% Cr, 9% Fe), Alloy 690 (60% Ni, 30% Cr, 9% Fe) and Alloy 800 (47% Fe, 32% Ni, 21% Cr) exposed to simulated, pressurised water reactor primary water at 325 °C has been compared. From the combination of chemical and structural data obtained by XPS, nuclear reaction analysis and scanning electron microscopy, the chemical composition and the morphology of the oxide formed on the surfaces have been determined. All alloys present a duplex oxide layer composed of Fe-rich crystals in the external layer and an inner Cr-rich layer that is compact and continuous. The oxide thicknesses were 4-20 nm for Alloy 600 exposed for 0-400 h, 4-40 nm for Alloy 690 exposed for 0-400 h and 4-150 nm for Alloy 800 exposed for 0 to 150 h. The kinetics of oxidation of these samples most probably fit a logarithmic growth equation.

International audience; SCIPION is a new state of the art digital sounder that has been devoloped by France Telecom-CNET for ionospheric monitoring and research. Extensive data processing using DSP technology has resulted in a low power, low cost and full featured system for both vertical and oblique soundings. A SCIPION system is in the process of being installed in Dakar, Senegal, to study HF propagation in the sub-equatorial ionosphere. However, preliminary results have still been obtained during experiments wit a prototype system. In this paper, the system is described and some illustrative examples of its capabilities are shown.Keywords. Ionosphere (Equatorial ionosphere, Instruments and Techniques) &#x22C5 Radio science (ionospheric propagation).

The dynamical behavior of γ-Fe2O3 particles dispersed in a polymer have been investigated by a.c. susceptibility and Mossbauer spectroscopy measurements. The effect of interparticle interactions on the relaxation time is satisfactorily described by a superparamagnetic model where the dipolar energy is determined by a statistical calculation for a disordered arrangement of particles with volume distribution and easy axes in random orientations. The results indicate that the single particle anisotropy energy is mainly determined by surface anisotropy and that the energy barrier increases with the interaction strength. © 1998 John Wiley & Sons, Ltd.

Despite some progress, the mortality of severe sepsis and septic shock remains high. Immunotherapy directed against inflammatory mediators failed, but new treatments more specifically tailored to individual situations are actively investigated. C-reactive protein (CRP) and procalcitonin (PCT) have not demonstrated to be useful for individual prognostic stratification. New biomarkers such as pancreatic stone protein (PSP) or growth arrest specific protein 6 (Gas6) could improve this prediction. Combined with the clinical course, "PCT" allows to tailor individually the duration of antibiotic therapy in ICU patients. This still contested innovative approach significantly reduces overall exposure to antibiotics.

Manufacture fiber amplifiers and lasers in a versatile and cost effective way while controlling rare-earths chemical environment becomes a real technology differentiator. A MCVD compatible Nanoparticle Doping Process has been developed to master with a higher accuracy rare earth amplifier and ytterbium laser fibers. Improved doped erbium fibers with C-band gain shape were obtained with much less aluminum content and unprecedented low background attenuation losses. This process should better show its merits in high power regime paving the way to fiber amplifiers and lasers for low cost new performances.

Fe2O3 nanoparticles dispersed in a polymer matrix have been characterized by x-ray diffraction (XRD) and transmission electron microscopy (TEM). The electron paramagnetic resonance (EPR) in 64 A particles of -Fe2O3 dispersed in a polymer matrix has been investigated in the range 136 - 286 K.

The kinetics of passivation, in high temperature and high pressure water, of nickel-chromium-iron alloys (Alloy 600, Alloy 690) have been investigated by X-ray Photoelectron Spectroscopy (XPS). The samples have been exposed for short (0–8 min) and longer (0 – 400 hours) time periods to high temperature (325°C) and high pressure water, with boron and lithium, under controlled hydrogen pressure. The fit of the data for short passivation times by three classical kinetics models (parabolic, logarithmic and inverse logarithmic laws) and the extrapolation to longer times reveal that the kinetics of passivation (formation of the internal Cr2O3 layer) of Alloy 600 and Alloy 690 in high temperature and high pressure water are in good agreement with a logarithmic model.

Colloidal aqueous suspensions of goethite lath-shaped nanorods form nematic and isotropic phases. We show that they also display a 2D rectangular (c2mm) columnar phase at volume fractions phi larger than 15%. Interestingly, the nematic-columnar first-order transition can also be triggered by applying to the nematic phase a magnetic field of intensity decreasing with phi (1 T at 8.5%; 0.5 T at 12%). Single domains of the columnar phase were thus produced and their structure investigated by synchrotron x-ray scattering. This magnetic-field-induced transition is fully reversible and reproducible.

Des activites caseine phosphatases endocellulaires et parietales, mesurees par la dephosphorylation d'un substrat specifique ([ 32 P]caseine), ont ete retrouvees chez plusieurs souches de bacteries lactiques largement utilisees en industrie fromagere (trois souches de Lactococcus lactis, deux souches de Lactobacillus helveticus et une souche de Streptococcus thermophilus). A l'inverse, la souche testee de Lactobacillus plantarum ne presentait aucune activite phosphatase notable. La souche de L. lactis ayant les meilleures activites au cours de sa croissance a ete retenue pour les etudes de caracterisation enzymatique. L'activite endocellulaire etait une phosphatase alcaline (pH optimum de 8) fortement dependante du magnesium et inhibee par 20 mM de fluorure de sodium. L'activite parietale consistait en une phosphatase acide (pH optimum de 4,5) tres peu affectee par la presence de magnesium et de NaF. Ces deux enzymes etaient differemment inhibees par d'autres composes du lait ou du fromage (phosphate, calcium, chlorure de sodium), l'activite parietale etant toujours moins affectee que l'activite endocellulaire. Les deux enzymes ont dephosphoryle de maniere significative de la caseine totale a pH 6,6, pH initial du lait et peuvent donc apparaitre comme des sources potentielles d'activites phosphatases en technologie fromagere.

Expected acceptability and actually taste acceptability of meat and other foods were determined in elderly subjects. Subjects gave an acceptability score, followed by a free description of the strong and weak points, first from memory during an interview and then after tasting each food. Taste acceptabilities of lamb, fish, poultry, veal and pork were similar to those expected during the interview. Significant discrepancies between observed and expected acceptability were found for beef, processed pork, eggs and rabbit meat. Beef was described as tough after tasting while it was expected as being tender in the interview; processed pork was associated with good quality and good texture during tasting whereas, too fatty with no strong points were expected in the interview; rabbit was criticized for dry texture more often in the interview than after tasting; eggs were popular for their soft texture and good taste but associated with too fatty and bad quality in the interview. The expected acceptability of processed pork, eggs and rabbit seemed to be governed by negative images of fatness or dryness and that of beef by a positive image of tenderness, which related poorly with tasting experience. L'acceptabilite estimee et effective des personnes agees pour differents types d'aliments sont determinees. Les degustateurs notent le produit puis le decrivent librement en insistant sur les points forts et faibles de memoire d'abord, puis apres la degustation. Pour l'agneau, le poisson, la volaille,le veau et le porc les acceptabilites lors de l'interview et de la degustations sont similaires. Par contre, des differences apparaissent pour le boeuf, le porc transforme, les oeufs et le lapin.

Knowledge of microbiological behavior in foods is a prerequisite to food processing quality control. From the mid eighties to the mid nineties, much research established growth and secondary models adapted to the main food pathogens, taking into consideration ecology factors such as temperature, pH, and Nacl concentration. This work led to the development of software to predict micro-organism growth. These devices were found however to be of little use because growth in limit conditions was poorly estimated and food composition or structure were not considered. More factors have to be taken into account when building a useful and informative tool for diagnosis. Food data and impact of food processing must be considered.

Several series of γ-Fe 2 O 3 nanoparticles dispersed in a polymer have been studied by means of various techniques. The variation of the relaxation time of the magnetic moment of the particle is in very good agreement with the Neel-Brown and our interparticle interaction models which lead to a reduced damping constant varying between 0.08 and I. For non interacting particles, the main component of the anisotropy comes from the surface. For interacting particles, the interaction energy includes dipolar and surface induced contributions. The susceptibility in the superparamagnetic state shows a strong dependence of the results on the external shape of the sample and the direction of applied field, very well checked experimentally, which is well interpreted with the Onsager model.

Various pathways to obtain γ-Fe2O3 nanoparticles by oxidizing colloidal magnetite are reported, with focus on resulting variations in surface structural features. Some outstanding surface properties of γ-Fe2O3 are pointed out. With a few examples it is shown how surface phenomena can enable to tailor the material for a wide range of utilizations.

The rates of uptake of exogenous L[U-14C] aspartate and glutamate into tissues of vegetative growing tips ofFucus serratus and their metabolism were studied in the dark. In these non-photosynthetic conditions, aspartate was fixed and metabolically converted more rapidly than glutamate. Radioactivity from14C-aspartate was principally transferred into glutamate. On the other hand, metabolism of absorbed14C-glutamate was very slow and its rate did not increase during incubation time, but produced more diversified soluble radioactive compounds. Thus inF. serratus, glutamate principally seems to be in the dark more a temporary14CO2 storage product coming from β-carboxylation than a rapidly turned over intermediate.

The intensity and fate of 14CO2-fixation in the dark are studied on Fucus serratus apices previously maintained under low illumination conditions using white, blue, red or yellow isoquantic lights.

Spinel iron oxide cationic sol flocculated by various agents, acids and bases, has been investigated by Mossbauer spectrometry. On the basic of chemical results, surface effects and inter-particle magnetic interactions have been characterized.

Description d’une nouvelle Gregarine : Anisolobus desportis n. sp. parasite de Cratopus frappieri Deyr. (Coleoptera Curculionidae) de la Reunion et considerations sur le genre Anisolobus qui aurait peut-etre chez certaines de ses especes une multiplication vegetative rappelant celle de representants du genre Gigaductus.

Chemical and structural studies of Fe(II) adsorption by iron oxide colloids are reported. The implications of surface-to-core electron transfer are deduced.

The chromosomal analysis ofT. intricata Hald. has shown a diploid complement of 44 chromosomes, the highest number found inTimarcha and clearly different from those of the taxa previously studied. This complement favours a derivative origin of theAmericanotimarcha subgenus from a hypothetical ancestral species of 20 chromosomes. The implications of this karyotype are also discussed with some morphological, biogeographical and ecological points of view and observations.

Stylocephalus africanus Theod., Desp. et Jolivet 1965 est signale chez un nouvel hote : Zophosis trilineata 01. (Col. Tenebrionidae) du Senegal.