Showing papers by "Pierre-and-Marie-Curie University published in 1982"
469 citations
TL;DR: In this article, the authors used field analyses together with interpretation of aerial photographs, orbital imagery and Sea-Beam data to define more accurately the geometry of fault systems in the Hellenic arc.
386 citations
TL;DR: In this article, it was shown that self-consistent calculations of the electronic charge density in large periodic cells containing a single displaced atom provide all the information needed for ab initio determination of force constants, phonon dispersion curves, effective charges, and the static dielectric constant.
Abstract: It is shown that self-consistent calculations of the electronic charge density in large periodic cells containing a single displaced atom provide all the information needed for ab initio determination of force constants, phonon dispersion curves, effective charges, and the static dielectric constant. Results are presented for GaAs.
316 citations
TL;DR: The Streckeisen QAP diagram discriminates four characteristic type series among the large variety of granitoids associated in intrusions as discussed by the authors, which integrate varied compositions from basic to acid terms.
255 citations
TL;DR: It is concluded that the uptake of nitrate does not discriminate among nitrogen isotopes and isotopic fractionation was null.
Abstract: Nitrogen isotope fractionation by Pearl Millet ( Pennisetum americanum L. and P. mollissimum L.) grown on nitrate was associated with nitrate reductase activity. Fractionation was evidenced at the step of nitrate reduction when the substrate-to-enzyme ratio was high (possibly saturating for the active sites of the nitrate reductase enzyme), for instance in young seedlings having a low nitrate reductase activity or in seedlings grown on high nitrate concentration. When the substrate concentration was low (and, hence, the active sites of the enzyme were possibly not saturated), the isotopic discrimination could only be associated with the uptake of nitrate into the cell. In that case, isotopic fractionation was null. It is concluded that the uptake of nitrate does not discriminate among nitrogen isotopes.
243 citations
TL;DR: In this article, macroscopic entropy balance equations for components, momentum and energy are established for a multiphase flow with diffusion, chemical reactions, heat transfer and exchanges of components between phases in a porous medium.
229 citations
TL;DR: The Friedel sum rule for impurities is related to the Luttinger requirement that the volume of the Fermi surface of a crystal is independent of interactions as discussed by the authors.
Abstract: The Friedel sum rule for impurities is related to the Luttinger requirement that the volume of the Fermi surface of a crystal is independent of interactions. As a consequence important results derived by use of the Friedel sum rule, e.g., the $T\ensuremath{\rightarrow}0$ properties of the Kondo problem, can be extended to periodic cases. Considered explicitly are the remarkable consequences for Fermi surfaces and Fermi-liquid properties of periodic Kondo and mixed-valence systems.
222 citations
TL;DR: In this paper, the Garsia-Rodemich-Rumsey lemma was used to obtain improvements of the Burkholder-Davis-Gundy inequalities for continuous martingales.
219 citations
TL;DR: In this article, the generalized Einstein equations derived from the Lagrangian were investigated and an approximate solution without singularity was constructed using the method of matched asymptotic expansions.
Abstract: We investigate the generalized Einstein equations derived from the Lagrangian which is an arbitrary function ofR. The importance of the saturation phenomenon is underlined, which may replace the role of a cosmological constant. The spherically symmetric homogeneous model is analyzed in more detail, and an approximate solution without singularity is constructed using the method of matched asymptotic expansions.
197 citations
TL;DR: In this article, the authors present results from extensive Monte Carlo simulations of the fluid phase of the two-dimensional classical one-component plasma (OCP) and compare these results to those obtained for a planar system with screened Coulomb interactions and periodic boundary conditions.
Abstract: We present results from extensive Monte Carlo simulations of the fluid phase of the two-dimensional classical one-component plasma (OCP). The difficulties associated with the infinite range of the logarithmic Coulomb interaction are eliminated by confining the particles to the surface of a sphere. The results are compared to those obtained for a planar system with screened Coulomb interactions and periodic boundary conditions; in this case the infinite tail of the Coulomb interaction is treated as a perturbation. The “exact” simulation results are used to test various approximate theories, including a semiempirical modification of the hypernetted-chain (HNC) integral equation. The OCP freezing transition is located at a couplingγ= e2/kBT−140.
193 citations
TL;DR: In this article, a model for nucleon-antinucleon annihilation which is of short range but is state (energy, spin, isospin,...) dependent as dictated by the calculation of annihilation diagrams is presented.
Abstract: A model has been constructed for nucleon-antinucleon annihilation which is of short range but is state (energy, spin, isospin, ...) dependent as dictated by the calculation of annihilation diagrams. This model fulfills general theoretical requirements and, at the same time, provides a good fit of the presently available pp-bar experimental data; better than the existing models which are state independent but effectively long ranged. The present results contradict the generally accepted claim that fitting the pp-bar data requires an effective long-ranged annihilation potential.
TL;DR: In this article, the authors reviewed a number of artefactual limitations in the current EXAFS analysis and suggested an efficient correction of the effects of X-ray leakage is suggested whereas the presence or the elimination of harmonics can be assessed by monitoring the reproducibility of the edge jump when calibrated metallic foils of different nature are inserted behind the sample.
Abstract: This paper is reviewing a number of artefactual limitations in the current EXAFS analysis. In conventional absorption measurements, the major sources of errors are the transmission of harmonics by the monochromator and inevitable leakages of radiation around or through the sample. The consequences are an alteration of the amplitude of the signal but also some harmonic distortion of the EXAFS oscillations and a systematic perturbation of the measured Debye-Waller terms. An efficient correction of the effects of X-ray leakage is suggested whereas the presence or the elimination of harmonics can be assessed by monitoring the reproducibility of the edge jump when calibrated metallic foils of different nature are inserted behind the sample. The basic analysis developed for absorption measurements has been successively extended to the case of REFLEXAFS and various emission techniques : X-ray fluorescence/scattering, optical luminescence and total electron yield. It became possible to rationalize a number of experimental observations and to determine appropriate operating conditions.
TL;DR: Equations giving the intensity, the divergence, and the radius of the modified beam are derived in simple practical form for experimentalists and show that, even in the case of negligible power losses through the aperture, the diffracted beam characteristics may appreciably differ from those of the incident beam.
Abstract: A Gaussian beam weakly diffracted by a circular aperture can be approximated in the far field by another Gaussian beam with slightly different characteristics. Equations giving the intensity, the divergence, and the radius of the modified beam are derived in simple practical form for experimentalists. These approximated formulas show that, even in the case of negligible power losses through the aperture, the diffracted beam characteristics may appreciably differ from those of the incident beam. In a first approximation, diffraction effects may be ignored only if the ratio a/r(0) of the aperture radius a to the l/e intensity beam radius r(0) in the aperture plane is larger than 3.
TL;DR: In this article, the role of partial melting in the uniform lithospheric stretching model of continental margin formation is explored and the implications for the existence of deep continental margin basins on thinned continental crusts are examined.
Abstract: The role of partial melting in the uniform lithospheric stretching model of continental margin formation is explored. It is shown that the transition from continental lithosphere stretching to oceanic accretion is most probably controlled by the production of a significant amount of partial melting in the asthenosphere immediately below the lithosphere, which requires stretching factors larger than 3. It is also shown that, at stretching factors exceeding 2, the law of subsidence is significantly changed by the presence of partial melt in the underlying asthenosphere. The implications for the existence of deep continental margin basins on thinned continental crusts are examined. The Armorican deep continental margin basin is taken as an example.
TL;DR: In this paper, a generalization of the XXZ model where the spin takes n + 1 values, and the hamiltonian is not parity invariant, is presented, where the diagonalization problem is solved exactly by the use of the n nested Bethe ansatz.
TL;DR: In this paper, two oxydes doubles, K 4 Nb 6 O 17 and K 2 Rb 2 Nb6 O 17, 5H 2 O, ont ete synthetises en monocristaux.
TL;DR: In this article, the major and trace elements of several lherzolite-type bodies were investigated and it was shown that these bodies have undergone a rather complex series of events including successive partial meltings and subsequent differentiation of the melts produced.
Abstract: Major and trace elements of several lherzolite-type bodies—at Lherz–Freychinede (French Pyrenees), Beni-Bouchera (Morocco), Lanzo (Italian Alps)—have been investigated. Quantitative model analysis of the element distributions shows that these bodies have undergone a rather complex series of events including successive partial meltings and subsequent differentiation of the melts produced. These events are related to the geodynamic evolution of these bodies within the upper mantle, and thus illustrate the multi-stage history of mantle material.
TL;DR: In rape seed, low temperatures and low light intensities increase the level of linoleic acid at the expense of oleic acid biosynthesis without change in plant growth.
TL;DR: In this paper, a distinction is made between C-type granites (crustal) and M-type (mantle or mixed i.e., crustal + mantle) granites.
TL;DR: In this article, the definition of l'integrale stochastique par rapport a un processus gaussien generalise donnee par Skorohod was presented.
TL;DR: In this paper, a more functional role of lipids was proposed and it was suggested that specific arrangements of components necessary for the functioning of the light reactions of photosynthesis can be regulated to a large extent by the lipid content of the membrane.
TL;DR: Improved values for the excitation rate coefficients of the Ti xxi resonance line, the intercombination lines, and the forbidden line, and new theoretical results on the wavelengths and transition probabilities for berylliumlike satellites due to transitions of the type 1${s}^{2}$2lnl'-1s2p2l''nl''' with n=2\char21{}4 have been calculated.
Abstract: K\ensuremath{\alpha} x-ray spectra of heliumlike titanium, Ti xxi, from Tokamak Fusion Test Reactor (TFTR) plasmas have been observed with a high-resolution crystal spectrometer and have been used as a diagnostic of central plasma parameters The data allow detailed comparison with recent theoretical predictions for the Ti xxi heliumlike lines and the associated satellite spectrum in the wavelength range from 26000 to 26400 A\r{} Improved values for the excitation rate coefficients of the Ti xxi resonance line, the intercombination lines, and the forbidden line, and new theoretical results on the wavelengths and transition probabilities for berylliumlike satellites due to transitions of the type 1${s}^{2}$2lnl'-1s2p2l''nl''' with n=2\char21{}4 have been calculated
TL;DR: In this article, the Bethe-ansatz equations of the chiral-invariant Gross-Neveu model are reduced to a simple form in which the parameters of the vacuum solution have been eliminated.
TL;DR: An extragenic suppressor mutation, mim2–1, which compensates yeast mitochondrial mutants deficient in splicing of the cytochrome b gene, has been mapped and sequenced and evolution and regulatory connections between homologous introns of nonhomologous genes are discussed.
Abstract: An extragenic suppressor mutation, mim2-1, which compensates yeast mitochondrial mutants deficient in splicing of the cytochrome b gene, has been mapped and sequenced. The mutation is due to a single G leads to A transition in the long open reading frame of the fourth intron of the oxidase subunit one gene. It causes the replacement of a glutamic codon by a lysine codon and the expression of a novel mRNA maturase active in splicing. Evolution and regulatory connections between homologous introns of nonhomologous genes are discussed.
Stanford University1, CERN2, Harvard University3, Vanderbilt University4, General Electric5, University of California, Santa Barbara6, Hewlett-Packard7, Lawrence Berkeley National Laboratory8, Fermilab9, Alcatel-Lucent10, University of Paris11, IBM12, University of California, Berkeley13, Pierre-and-Marie-Curie University14, Université Paris-Saclay15, Massachusetts Institute of Technology16, University of Illinois at Urbana–Champaign17
TL;DR: In this article, the authors measured multihadron production in e+e− annihilation at center-of-mass energies between 2.6 and 7.8 GeV and found that the total hadronic cross section was approximately 2.7 times the cross section for the production of muon pairs at c.m.
Abstract: Measurements of multihadron production in e+e− annihilation at center-of-mass energies between 2.6 and 7.8 GeV are presented. Aside from the narrow resonances ψ(3095) and ψ(3684), the total hadronic cross section is found to be approximately 2.7 times the cross section for the production of muon pairs at c.m. energies below 3.7 GeV and 4.3 times the muon-pair cross section at c.m. energies above 5.5 GeV. Complicated structure is found at intermediate energies. Charged-particle multiplicities and inclusive momentum distributions are presented.
TL;DR: In this paper, a detailed bathymetric investigation was performed in four zones of the Hellenic trench system in 1978, using the multi-narrow beam echo-sounder "Sea-Beam" on R.V. "Jean Charcot", and the results showed that compressional structures affect the sedimentary cover of the outer wall and trench whereas extensional tectonics is present on the inner wall.
TL;DR: New data on the ultrastructural features of the elasmoid scales of Carassius auratus have been obtained by use of rapid freezing with subsequent freeze-substitution in anhydrous solvents, compared with the results obtained using conventional aqueous fixatives.
Abstract: New data on the ultrastructural features of the elasmoid scales ofCarassius auratus have been obtained by use of rapid freezing with subsequent freeze-substitution in anhydrous solvents. These are compared with the results obtained using conventional aqueous fixatives. The external layer of the scales is composed of randomly oriented collagen fibres. In the first stages of mineralization, mineral deposits are located in the interfibrillary substance where dense granules appear to be active sites of mineralization. Spheritic mineralization occurs in this layer. The fibrillary plate is composed of two kinds of collagen fibres. Most of them are organized in lamellae forming the “plywood-like structure”. They are thicker than the so-called “TC fibres”, which are oriented from the basal part towards the superficial layer. These TC fibres are involved in the first stages of mineral deposition in the fibrillary plate where inotropic mineralization occurs. The mineral phase is almost always located in the interfibrillary matrix in both layers of the elasmoid scale. In this respect, teleost scales differ from those described so far in other lower vertebrates.
TL;DR: In this paper, the pore texture of Raney-nickel was determined by impedance measurements carried out over a wide frequency range and the impedance obtained could be characterized by three resistances, R, Re and Rt and one capacitor C. R is the high frequency limit of the electrode impedance, and is equal to the electrolyte resistance between the reference capillary tip and the upper surface of catalyst layer.
TL;DR: A phospholipid transfer protein has been purified 125-fold from maize seedlings and a labelled phosphatidylcholine-protein complex was obtained after chromatofocusing, suggesting that the protein acts by carrying phosphorus from a membrane toward another one.