Detection of Jovian seismic waves: a new probe of its interior structure

Knowledge of Jupiter's deep interior would provide unique constraints on the formation of the Solar System. Measurement of its core mass and global composition would shed light on whether the planet formed by accretion or by direct gravitational collapse. At present, the inner structure of Jupiter is poorly constrained and seismology, which consists of identifying acoustic eigenmodes, offers a way to directly measure its deep sound speed profile, and thus its physical properties. Seismology of Jupiter has been considered since the mid 1970s, but hitherto the various attempts to detect global modes led, at best, to ambiguous results. We report the detection of global modes of Jupiter, based on radial velocity measurements performed with the SYMPA Fourier spectro-imager. The global seismic parameters that we measure include the frequency of maximum amplitude 1213+/-50 \mu Hz, the mean large frequency spacing between radial harmonics 155.3+/-2.2 \mu Hz and the mode maximum amplitude 49 (-10/+8) cm/s, all values that are consistent with current models of Jupiter. This result opens the way to the investigation of the inner structure of the Solar System's giant planets based on seismology techniques.Comment: Accepted in Astronomy & Astrophysics (8 pages, 9 figures

La ville et son élan vital

Si Marcel Poëte et Robert Auzelle ont parlé de ville vivante, c'est pour une large part dans un rapport constant à la philosophie de Bergson. Le mouvement créateur de la ville, observé par l'historien et mis en œuvre par l'urbaniste, exige pour être compris une implication de tout être dans l'élan vital. C'est cette notion bergsonienne, longtemps travaillée par Poëte, qui se fait jour dans les travaux comme dans les écrits d'Auzelle. De Bergson à Poëte, puis de Poëte à Auzelle, des idées philosophiques d'abord étrangères à l'urbanisme passent en se transformant dans l'histoire des villes et dans la réalisation urbaine.Marcel Poëte and Robert Auzelles'theoires about the town as an evolving crea­tion are directly connected to Bergson's philosophy. Poëte, the historian, saw the creative movement in the evolution of a town and Auzelle, the town-planner, embraced this in his town planning. This concept of the town as a living, evolving organism can only be fully understood by those who are personally involved in the vital impulse. Poëte thought of this Bergsonian concept and this appears in Auzelle's writings and urban develop­ments. From Bergson to Poëte, then from Poëte to Auzelle, philosophical concepts, at first apparently irrelevant to town planning, evolved to become helpful to understand history of towns and to take part in the creation of town

La Société française des urbanistes et l’Institut d’urbanisme : deux usages du réseau pour une même cause ?

En 1911 est créée la Société française des architectes et urbanistes, elle devient en 1919 la SFU. Issue du Musée social, sa vocation est de promouvoir une science et un art urbain pour l’amélioration des villes. Le réseau des réformateurs sociaux a croisé celui de certains architectes pour lui donner naissance.L’Institut d’urbanisme intègre l’Université en 1924 après avoir connu divers statuts. Sa genèse est étrangère aux acteurs de la SFU : son réseau de fondation est lié à l’Université et aux institutions publiques.Peu d’acteurs ont appartenu en même temps à ces deux créations pour la promotion de l’urbanisme. On étudiera ici le rôle des réseaux de fondation et l’originalité de leurs fonctionnements. L’usage du réseau est en effet déterminant pour l’idée même d’urbanisme dans les deux premières décennies du xxe siècle

Effets de phytobiotiques sur les performances de croissance et l'équilibre ou microbiote digestif du poulet de chair

Suite à l interdiction de l utilisation des antibiotiques facteurs de croissances dans l alimentation animale en 2006, des méthodes alternatives sont proposées aux éleveurs, notamment les phytobiotiques. Cependant, l efficacité de ces molécules, telle que décrite dans la littérature, est variable, et leur modes d action est mal connu. Nous avons pu mettre en évidence un effet important des conditions d élevage dans la réponse des poulets aux deux modèles de phytobiotiques étudiés. Ils améliorent les performances zootechniques des animaux placés dans des conditions défavorables à leur croissance. Dans des conditions très dégradées, l utilisation couplée de phytobiotiques portant des activités biologiques variées s est avéré plus efficace. De plus, les modèles étudiés comprenant de nombreuses molécules exerçant une activité antibactérienne in vitro, nous avons étudié in vivo la réponse du microbiote digestif à leur ingestion par l animal. Des modifications du microbiote digestif ont été observées et pourraient en partie expliquer l amélioration de leur croissance.The banning of antibiotic growth promoters for livestock feeding led to the development of several alternatives, including phytobiotics. However, their efficiency as growth promoters is inconstant between scientific studies and their mechanisms of action are poorly known. In the present work, the rearing conditions strongly affect the efficiency of two phytobiotics models. They improved the chickens growth performance when the rearing conditions were unfavorable to the growth. When strongly deteriorated, the combination of phytobiotics showing various biological activities was more efficient. As the phytobiotics used in the present study contains numerous molecules with an in vitro antibacterial activity, the impact of those phytobiotics on chickens digestive microbiota was studied in vivo. Changes in chickens digestive microbiota were observed which could partly explain the chickens growth improvement.TOURS-Bibl.électronique (372610011) / SudocSudocFranceF

A chemical survey of exoplanets with ARIEL

Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

Rapid response to the M_w 4.9 earthquake of November 11, 2019 in Le Teil, Lower Rhône Valley, France

On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to large damages it produced in several villages. InSAR interferograms indicated a shallow rupture about 4 km long reaching the surface and the reactivation of the ancient NE-SW La Rouviere normal fault in reverse faulting in agreement with the present-day E-W compressional tectonics. The peculiarity of this earthquake together with a poor coverage of the epicentral region by permanent seismological and geodetic stations triggered the mobilisation of the French post-seismic unit and the broad French scientific community from various institutions, with the deployment of geophysical instruments (seismological and geodesic stations), geological field surveys, and field evaluation of the intensity of the earthquake. Within 7 days after the mainshock, 47 seismological stations were deployed in the epicentral area to improve the Le Teil aftershocks locations relative to the French permanent seismological network (RESIF), monitor the temporal and spatial evolution of microearthquakes close to the fault plane and temporal evolution of the seismic response of 3 damaged historical buildings, and to study suspected site effects and their influence in the distribution of seismic damage. This seismological dataset, completed by data owned by different institutions, was integrated in a homogeneous archive and distributed through FDSN web services by the RESIF data center. This dataset, together with observations of surface rupture evidences, geologic, geodetic and satellite data, will help to unravel the causes and rupture mechanism of this earthquake, and contribute to account in seismic hazard assessment for earthquakes along the major regional Cévenne fault system in a context of present-day compressional tectonics

A Solve-RD ClinVar-based reanalysis of 1522 index cases from ERN-ITHACA reveals common pitfalls and misinterpretations in exome sequencing

Purpose Within the Solve-RD project (https://solve-rd.eu/), the European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies aimed to investigate whether a reanalysis of exomes from unsolved cases based on ClinVar annotations could establish additional diagnoses. We present the results of the “ClinVar low-hanging fruit” reanalysis, reasons for the failure of previous analyses, and lessons learned. Methods Data from the first 3576 exomes (1522 probands and 2054 relatives) collected from European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies was reanalyzed by the Solve-RD consortium by evaluating for the presence of single-nucleotide variant, and small insertions and deletions already reported as (likely) pathogenic in ClinVar. Variants were filtered according to frequency, genotype, and mode of inheritance and reinterpreted. Results We identified causal variants in 59 cases (3.9%), 50 of them also raised by other approaches and 9 leading to new diagnoses, highlighting interpretation challenges: variants in genes not known to be involved in human disease at the time of the first analysis, misleading genotypes, or variants undetected by local pipelines (variants in off-target regions, low quality filters, low allelic balance, or high frequency). Conclusion The “ClinVar low-hanging fruit” analysis represents an effective, fast, and easy approach to recover causal variants from exome sequencing data, herewith contributing to the reduction of the diagnostic deadlock