pinecone/core-2020-05-10-deduplication huggingface dataset:
The Cenozoic evolution of the Roer Valley Rift System integrated at a European scale

International audienceThe Roer Valley Rift System (RVRS) is located between the West European rift and the North Sea rift system. During the Cenozoic, the RVRS was characterized by several periods of subsidence and inversion, which are linked to the evolution of the adjacent rift systems. Combination of subsidence analysis and results from the analysis of thickness distributions and fault systems allows the determination of the Cenozoic evolution and quantification of the subsidence. During the Early Paleocene, the RVRS was inverted (Laramide phase). The backstripping method shows that the RVRS was subsequently mainly affected by two periods of subsidence, during the Late Paleocene and the Oligocene–Quaternary time intervals, separated by an inversion phase during the Late Eocene. During the Oligocene and Miocene periods, the thickness of the sediments and the distribution of the active faults reveal a radical rotation of the direction of extension by about 70–80j (counter clockwise). Integration of these results at a European scale indicates that the Late Paleocene subsidence was related to the evolution of the North Sea basins, whereas the Oligocene–Quaternary subsidence is connected to the West European rift evolution. The distribution of the inverted provinces also shows that the Early Paleocene inversion (Laramide phase) has affected the whole European crust, whereas the Late Eocene inversion was restricted to the southern North Sea basins and the Channel area. Finally, comparison of these deformations in the European crust with the evolution of the Alpine chain suggests that the formation of the Alps has controlled the evolution of the European crust since the beginning of the Cenozoic
Nonhomogeneous boundary conditions for the spectral fractional Laplacian

International audienceWe present a construction of harmonic functions on bounded domains for the spectral fractional Laplacian operator and we classify them in terms of their divergent profile at boundary. This is used to establish and solve boundary value problems associated with nonhomogeneous boundary conditions. We provide a weak-L 1 theory to show how problems with measure data at the boundary and inside the domain are well-posed. We study linear and semilinear problems, performing a sub-and supersolution method. We finally show the existence of large solutions for some power-like nonlinearities
The source-effort coverage of an exponential informetric process

International audienceLotkaian informetrics is the framework most often used to study statistical distributions in the production and usage of information. Although Lotkaian distributions are traditionally used to characterize the Information Production Process (IPP) , we have shown in a previous article that the IPP can successfully be studied using the effort function – the latter having been initially introduced to define the Exponential Informetric Process (EIP). These themes continue to be developed in this article , in which we present a necessary and sufficient condition for the existence of the EIP. Our current approach is similar to the one used to study IPPs. Inverse power and exponential distributions serve to illustrate the results obtained in the context of an EIP. Numerical examples are discussed
Higher-order spin effects in the dynamics of compact binaries II. Radiation field

includes the correction of an erratum to be published in Phys. Rev. DInternational audienceMotivated by the search for gravitational waves emitted by binary black holes, we investigate the gravitational radiation field of point particles with spins within the framework of the multipolar-post-Newtonian wave generation formalism. We compute: (i) the spin-orbit (SO) coupling effects in the binary's mass and current quadrupole moments one post-Newtonian (1PN) order beyond the dominant effect, (ii) the SO contributions in the gravitational-wave energy flux and (iii) the secular evolution of the binary's orbital phase up to 2.5PN order. Crucial ingredients for obtaining the 2.5PN contribution in the orbital phase are the binary's energy and the spin precession equations, derived in paper I of this series. These results provide more accurate gravitational-wave templates to be used in the data analysis of rapidly rotating Kerr-type black-hole binaries with the ground-based detectors LIGO, Virgo, GEO 600 and TAMA300, and the space-based detector LISA
Discovery of binarity, spectroscopic frequency analysis, and mode identification of the δ Scuti star 4 CVn

International audienceMore than 40 years of ground-based photometric observations of the δ Sct star 4 CVn has revealed 18 independent oscillation frequencies, including radial as well as non-radial p-modes of low spherical degree ℓ ≤ 2. From 2008 to 2011, more than 2000 spectra were obtained at the 2.1 m Otto-Struve telescope at the McDonald Observatory. We present the analysis of the line-profile variations, based on the Fourier-parameter fit method, detected in the absorption lines of 4 CVn, which carry clear signatures of the pulsations. From a non-sinusoidal, periodic variation of the radial velocities, we discover that 4 CVn is an eccentric binary system with an orbital period Porb = 124.44 ± 0.03 d and an eccentricity e = 0.311 ± 0.003. We detect 20 oscillation frequencies, 9 of which previously unseen in photometric data; attempt mode identification for the two dominant modes, f1 = 7.3764 d-1 and f2 = 5.8496 d-1; and determine the prograde or retrograde nature of 7 of the modes. The projected rotational velocity of the star, veqsini ≃ 106.7 km s-1, translates to a rotation rate of veq/vcrit ≥ 33%. This relatively high rotation rate hampers unique mode identification, since higher order effects of rotation are not included in the current methodology. We conclude that, in order to achieve unambiguous mode identification for 4 CVn, a complete description of rotation and the use of blended lines have to be included in mode-identification techniques
Poly(4-vinyl pyridine) radiografted PVDF track etched membranes as sensors for monitoring trace mercury in water

International audiencePoly-4-vinyl pyridine chains were radiografted inside the etched-tracks of PVDF nanoporous membrane. P4VP grafting was found to be localized on the solid PVDF surface. Coating of these PVDF-g-P4VP membranes with a very thin layer of gold results in an ASV electrochemical sensor. Functionalized ion track-etched PVDF-g-P4VP sensors were found very selective and highly sensitive for mercury LOD 5 ng/L. a b s t r a c t By a radiation-induced grafting technique, we have functionalized track-etched nanoporous polymer membranes with mercury sensitive poly-4-vinyl pyridine (P4VP). Coating of these membranes with a very thin layer of gold results in an electrochemical sensor that is very selective and highly sensitive for mercury LOD 5 ng/L – well below the norms for water (0.015 mg/L potable water and 0.5 mg/L residual waters-French water norms of 27 October 2011). E-beam irradiation permitted optimization of the radiografting synthesis on PVDF thin films prior to ion-track grafting. Synthesis and characterization by EPR, FESEM and FTIR are described in detail. A comparison between FTIR in ATR and transmission modes enabled us to localize the grafting on the surface of the e-beam irradiated PVDF films allowing us to extrapolate what happens on the etched tracks. Using Square Wave Anodic Stripping Voltammetry (SW-ASV), mercury concentrations of 1 mg/L are detected in 2 h and low ng/L concentrations are detected after 24 h of adsorption. The adsorption is passive so sensors do not require instrumentation and the analysis takes only 3–4 min. Also, the P4VP functionalized sensor appears insensitive to pH variations (pHs 3–9), high salt concentrations (up to 1 g/ L) and the presence of other heavy metals in the same solution.
Rheology of three-dimensional packings of aggregates: Microstructure and effects of nonconvexity

International audienceWe use 3D contact dynamics simulations to analyze the rheological properties of granular materials composed of rigid aggregates. The aggregates are made from four overlapping spheres and described by a nonconvexity parameter depending on the relative positions of the spheres. The macroscopic and microstructural properties of several sheared packings are analyzed as a function of the degree of nonconvexity of the aggregates. We find that the internal angle of friction increases with nonconvexity. In contrast, the packing fraction increases first to a maximum value but declines as nonconvexity further increases. At high level of nonconvexity, the packings are looser but show a higher shear strength. At the microscopic scale, the fabric and force anisotropy, as well as friction mobilization are enhanced by multiple contacts between aggregates and interlocking, revealing thus the mechanical and geometrical origins of shear strength
Anisotropy of strong pinning in multi-band superconductors

21 pages, Numéro spécial 2012 sur la supraconductivité à base de fer dans Superconducting Science and Technology (accepté)International audienceThe field-angular dependence and anisotropy of the critical current density in iron-based superconductors is evaluated using a phenomenological approach featuring distinct anisotropy factors for the penetration depth and the coherence length. Both the weak collective pinning limit, and the strong pinning limit relevant for iron-based superconductors at low magnetic fields are considered. It is found that in the more anisotropic materials, such as SmFeAsO and NdFeAsO, the field-angular dependence is completely dominated by the coherence-length (upper-critical field) anisotropy, thereby explaining recent results on the critical current in these materials. In less anisotropic superconductors, strong pinning can lead to an apparent inversion of the anisotropy. Finally, it is shown that, under all circumstances, the ratio of c-axis and ab-plane critical current densities for magnetic field along the ab-plane directly yields the coherence length anisotropy factor εξ
Application of smoothed particle hydrodynamics (SPH) and pore morphologic model 2 to predict saturated water conductivity from X-ray CT imaging in a silty loam Cambisol

International audience20 This study aims to estimate saturated hydraulic conductivity in a silty loam soil and compare modelled data with 21 experimental ones. The flow characteristics of twelve undisturbed soil cores (5 cm in diameter × 6 cm high) were 22 measured in the laboratory after performing X-ray computed microtomography (microCT) analysis. MicroCT 3D 23 imaging was integrated with an existing pore morphologic model and a numerical simulation based on mesh-24 free smoothed particle hydrodynamics (SPH) to calculate the water flow through the macropore network 25 (pores N 40 μm). Results showed that the proposed SPH method was able to predict hydraulic conductivity of 26 large-sized samples as falling in the range of the experimental ones. By contrast the morphologic model generally 27 underestimated the water flow and was slightly affected by the pore shape. Increasing microCT imaging resolu-28 tion and expanding the variability with other soil types will improve the understanding of the role of micropore 29 size and morphology on water conductivity. 3
Effect of sulphur on the structure of silicate melts under oxidizing conditions

International audienceIn magmatic systems, sulphur is an important volatile element after C, H and O. Under oxidizing conditions, S dissolves in aluminosilicate melt as sulphate groups (SO42 −). The way SO42 − groups dissolve in the melt is currently poorly understood. We present experimental results of the effect of SO42 − dissolution on the aluminosilicate melt structure. Glasses of haplogranitic (HPG) and anorthite-diopside eutectic (An-Di) compositions were synthesized at 300 MPa and 1250 °C and under oxidizing conditions (ΔFMQ + 1.7 to + 3.0). Starting compositions were equilibrated under fluid-saturated conditions with a mixture of S (0 to 5 wt.%) and H2O (5 wt.%). The S and H2O contents of the recovered glasses were determined with EPMA and FTIR, respectively. Solid state NMR was used to investigate the glass structure. Micro-Raman analyses were performed to identify S species present in glass and coexisting fluid phases. The S content determined in glasses changes from 0 to 979 ppm and 0 to 7519 ppm for HPG and An-Di, respectively. S is present in the glasses as Mn +SO42 − groups (Mn + is possibly Ca2 + in An-Di and Na+ in HPG). 29Si NMR analyses show important changes in the An-Di glass structure upon S dissolution. High S content in An-Di glasses induces a strong polymerization of the glass which we explain by the presence of non-bridging oxygen (NBO) promoting the dissolution of S as SO42 − groups. On the contrary, the dissolution of S within HPG melt does not produce visible changes in the silicate melt structure due to the low concentration in NBO in this melt composition. The observed structural changes suggest that An-Di melt physical properties might be affected by S dissolution. S might produce large changes in melt viscosity, but opposite, as compared to H2O for slightly depolymerized aluminosilicate melts
Pore-scale flow measurements at the interface between a sandy layer and a model porous medium: Application to statistical modeling of contact erosion

Contact erosion is potentially initiated at the interface between two soil layers by a groundwater flow within the coarser material. Once eroded by the flow, particles from the finer soil are transported through the pores of the coarser layer. Fluvial dikes are often exposed to this phenomenon. Small-scale experiments combining refractive index matching medium, planar laser-induced fluorescence, and particle image velocimetry were carried out to measure the flow characteristics in the vicinity of an interface between a model granular medium and a fine graded sandy layer. Longitudinal velocities and shear-stress distributions were obtained in Darcy flow conditions. They revealed a long tail toward large values, which reflects the spatial variability of the constrictions in the pores network. Taking into account these distributions can improve the modelling of contact erosion by going beyond the simple use of mean quantities, like Darcy velocity, as is usually proposed in the literature. This is done by successively considering the variability of the porous flow and also that of the critical shear stress. As a main consequence, the resulting global erosion rate is nownonzero for any value of the mean shear stress and there is no longer a stress threshold. Finally, the effect of paving at the sand surface can also be added to the statistical model and makes it possible to account very satisfactorily for previous contact erosion tests at the sample scale
Low-temperature wollastonite formed by carbonate reduction: a marker of serpentinite redox conditions

International audienceIn the Alpine blueschist- to eclogite-facies meta-ophiolitic units of northern Corsica, the contact between a serpentinite body and an immediately overlying siliceous marble is remarkable for the occurrence of wollastonite and, on the marble side, a dark halo around the serpentinite. The refolded, continuous contact is a rodingite-type reaction zone with a centimetre-thick nephritic selvage of diopside + andradite/grossular ± perovskite on the serpentinite side, followed towards the marble by a 1-5 cm thick zone of massive wollastonite (± grossular), followed by a 5-20 cm thick dark zone (the halo) consisting of wollastonite + quartz + graphitic material (± grossular ± diopside), with no carbonate. The transition to the overlying wollastonite-free, calcite + quartz-bearing layers is sharp. Considering the stability of calcite + quartz everywhere else in the regional metamorphic series, this low-temperature occurrence of wollastonite (c. 400-450°C) requires unusual conditions. A clue to its origin is the abundance of graphitic matter with the wollastonite within a few decimetres of the serpentinite body. We interpret this observation as evidence for local reduction of Ca-carbonate to form elemental carbon and wollastonite according to the reaction: SiO2 + CaCO3 + 2H2 = CaSiO3 + C + 2H2O. Thermochemical modelling of mineral stability in the successive reaction zones suggests a positive oxygen-fugacity gradient from the serpentinite to the marble (-6 < FMQ < -1), mediated through a CH4- and H2-bearing aqueous intergranular fluid
Asteroid (99942) Apophis: new predictions of Earth encounters for this potentially hazardous asteroid

Reproduced with permission. Copyright ESO.International audienceContext. The potentially hazardous asteroid (99942) Apophis, previously designated 2004 MN4, is emblematic of the study of asteroids that could impact the Earth in the near future. Orbit monitoring and error propagation analysis are mandatory to predict the probability of an impact and, furthermore, its possible mitigation. Several aspects for this prediction have to be investigated, in particular the orbit adjustment and prediction updates when new astrometric data are available. Aims: We analyze Apophis orbit and provide impact predictions based on new observational data, including several orbit propagations. Methods: New astrometric data of Apophis have been acquired at the Pic du Midi one-meter telescope (T1m) during March 2011. Indeed, this asteroid was again visible from ground-based stations after a period of several years of unfavorable conjunction with the Sun. We present here the original astrometric data and reduction, and the new orbit obtained from the adjustment to all data available at Minor Planet Center (until March 2011). Results: We present a new sketch of keyholes and impacts for the next century. Additionally, we discuss observational errors, astrometric reduction, orbit adjustment, and adequacy of the dynamical model used. Based on observations made at Pic du Midi station and data from IAU-MPC
Interaction between normal fault slip and erosion on relief evolution: Insights from experimental modelling

International audienceThe growth of relief in active tectonic areas is mainly controlled by the interactions between tectonics and surface processes (erosion and sedimentation). The study of long-lived morphologic markers formed by these interactions can help in quantifying the competing effects of tectonics, erosion and sedimentation. In regions experiencing active extension, river-long profiles and faceted spurs (triangular facets) can help in un- derstanding the development of mountainous topography along normal fault scarps. In this study, we devel- oped analogue experiments that simulate the morphologic evolution of a mountain range bounded by a normal fault. This paper focuses on the effect of the fault slip rate on the morphologic evolution of the foot- wall by performing three analogue experiments with different fault slip rates under a constant rainfall rate. A morphometric analysis of the modelled catchments allows comparing with a natural case (Tunka half- graben, Siberia). After a certain amount of fault slip, the modelled footwall topographies of our models reaches a dynamic equilibrium (i.e., erosion balances tectonic uplift relative to the base level) close to the fault, whereas the topography farther from the fault is still being dissected due to regressive erosion. We show that the rates of vertical erosion in the area where dynamic equilibrium is reached and the rate of re- gressive erosion are linearly correlated with the fault throw rate. Facet morphology seems to depend on the fault slip rate except for the fastest experiment where faceted spurs are degraded due to mass wasting. A stream-power law is computed for the area wherein rivers reach a topographic equilibrium. We show that the erosional capacity of the system depends on the fault slip rate. Finally, our results demonstrate the pos- sibility of preserving convex river-long profiles on the long-term under steady external (tectonic uplift and rainfall) conditions
Arsenic uptake by gypsum and calcite: Modeling and probing by neutron and x-ray scattering

Proceedings of the Eighth International Conference on Neutron ScatteringInternational audienceHere we report on two structural studies performed on As-doped gypsum (CaSO4 2H2O) and calcite (CaCO3), using neutron (D20-ILL) and x-ray (ID11-ESRF) diffraction data and EXAFS (BM8-ESRF). The aim of this study is to determine whether As gets into the bulk of gypsum and calcite structures or is simply adsorbed on the surface. Different mechanisms of substitution are used as hypotheses. The combined Rietveld analysis of neutron and x-ray diffraction data shows an expansion of the unit cell volume proportional to the As concentration within the samples. DFT-based simulations confirm the increase of the unit cell volume proportional to the amount of carbonate or sulphate groups substituted. Interpolation of the experimental Rietveld data allows us to distinguish As substituted within the structure from that adsorbed on the surface of both minerals
Joint source-channel coding: secured and progressive transmission of compressed medical images on the Internet

International audienceThe joint source-channel coding system proposed in this paper has two aims: lossless compression with a progressive mode and the integrity of medical data, which takes into account the priorities of the image and the properties of a network with no guaranteed quality of service. In this context, the use of scalable coding, Locally Adapted Resolution (LAR) and a discrete and exact Radon transform, known as the Mojette transform, meets this twofold requirement. In this paper, details of this joint coding implementation are provided as well as a performance evaluation with respect to the reference CALIC coding and to unequal error protection using Reed-Solomon codes