Showing papers by "École Normale Supérieure published in 1980"
TL;DR: Four assumptions are discussed in the chapter, in order to understand Compliance and Conversion, in which a consistent minority can exert an influence to the same extent as a consistent majority and that the former will generally have a greater effect on a deeper level, while the latter often has less at that level.
Abstract: Publisher Summary The chapter discusses two types of social behavior: compliance and conversion. Four assumptions are discussed in the chapter, in order to understand Compliance and Conversion. The four assumptions present a picture in which a consistent minority can exert an influence to the same extent as a consistent majority, and that the former will generally have a greater effect on a deeper level, while the latter often has less, or none, at that level. These assumptions allow formulating some interesting and verifiable predictions: (1) Conversion is produced by a minority's consistent behavior; (2) The conversion produced by a minority implies a real change of judgments or opinions; (3) The more intense the conflict generated by the minority, the more radical is the conversion; (4) At least where perceptions are involved, conversion is more pronounced when the influence source is absent. The chapter presents a certain number of facts that substantiate these predictions and make them more plausible. Experimental studies are also mentioned wherein preliminary results, direct and indirect influences, conflict and conversion behavior, minority influence, majority influence and compliance are discussed. Final observation indicates convergence between the elements of the proposed theory and the experimental illustrations of conversion behavior.
608 citations
TL;DR: In this article, a general definition of symmetries of gauge fields is proposed and a method developed for constructing symmetric fields for an arbitrary gauge group, where scalar fields occur naturally in the formalism and pure gauge theory reduces to a Higgs model in lower dimensions.
Abstract: A general definition of symmetries of gauge fields is proposed and a method developed for constructing symmetric fields for an arbitrary gauge group. Scalar fields occur naturally in the formalism and the pure gauge theory reduces to a Higgs model in lower dimensions.
567 citations
TL;DR: This paper derives several basic or abstract algorithms, already given in Ref. 1, and studies their convergence properties in the framework of i infinite-dimensional convex programming.
Abstract: The auxiliary problem principle allows one to find the solution of a problem (minimization problem, saddle-point problem, etc.) by solving a sequence of auxiliary problems. There is a wide range of possible choices for these problems, so that one can give special features to them in order to make them easier to solve. We introduced this principle in Ref. 1 and showed its relevance to decomposing a problem into subproblems and to coordinating the subproblems. Here, we derive several basic or abstract algorithms, already given in Ref. 1, and we study their convergence properties in the framework of i infinite-dimensional convex programming.
385 citations
TL;DR: A highly sensitive and simple photothermal scheme for determining optical absorptions in condensed matter samples and a comparison with thermal lens effect is given.
Abstract: We present a highly sensitive and simple photothermal scheme for determining optical absorptions in condensed matter samples. {alpha}l values as low as 10{sup -7} and 10{sup -8} were measured for thin films and coatings and for liquids, respectively. A comparison with thermal lens effect is given, and the experimental factors limiting our sensitivity are discussed.
313 citations
TL;DR: In the intertropical cold dry phase from ∼20,000 to 12,500 yr BP, the aggrading Nile was a braided, highly seasonal river as mentioned in this paper, and with a headwaters change to warmer, wetter conditions, it became an incised, sinuous, suspended load river.
Abstract: During the intertropical cold dry phase from ∼20,000 to 12,500 yr BP, the aggrading Nile was a braided, highly seasonal river. With a headwaters change to warmer, wetter conditions, it became an incised, sinuous, suspended load river. Overflow from Lake Victoria and severe floods in Egypt heralded the change in Nile regime.
266 citations
TL;DR: In this paper, the authors formulate on-shell 11-dimensional supergravity in superspace and express its equations of motion in terms of purely geometrical quantities, where all torsion and curvature components are solved by a single superfield, totally antisymmetric in its (flat vector) indices.
227 citations
TL;DR: In this paper, the effects of influence attempts by a majority and by a minority were examined on both a manifest response level and a latent perceptual level, and it was predicted that the subject's judgment of the chromatic afterimage would be modified when the influence agent represented a minority.
179 citations
177 citations
TL;DR: R-banding of lymphocytes and fibroblasts from 11 patients with ataxia telangiectasia showed rearrangements of chromosomes 7 and/or 14 in about 7% of the cells, and pericentric inversion of chromosome 7 was the most frequent, and the paracentric inversions of chromosome 14 not very rare.
Abstract: The R-banding of more than 1100 lymphocytes and fibroblasts from 11 patients with ataxia telangiectasia (AT) showed rearrangements of chromosomes 7 and/or 14 in about 7% of the cells. Among these rearrangements, pericentric inversion of chromosome 7 was the most frequent, and the paracentric inversion of chromosome 14 not very rare. These inversions are believed to be fairly specific of AT, and their absence in the previously reported literature may be due to technical problems. Inversions were also observed in the lymphocytes of presumed heterozygote carriers with a lower frequency, and may be of some help for the detection of healthy heterozygote carriers of the AT gene.
166 citations
TL;DR: The 40Ar-39Ar method has been applied to high pressure (HP) white micas from the Gran Paradiso crystalline massif and from the overthrust Schistes Lustres of its western slope.
Abstract: The40Ar-39Ar method has been applied to high pressure (HP) white micas from the Gran Paradiso crystalline massif and from the overthrust Schistes Lustres of its western slope. Preliminary petrographic and microanalytical investigation of the phengite micas showed that their celadonite-content decreases with time (from Si3.65 to Si3.05), and that less foliated samples are the most suitable for the metastable persistence of the high celadonite-content of the early HP stage during subsequent metamorphic evolution.
150 citations
TL;DR: In this article, a synthese stereospecifique du p-tolylsulfinyl acetate de t-butyle is described, which permet de realiser, par une condensation du type aldol, des syntheses asymetriques de β-hydroxyacides avec des rendements chimiques de l'ordre de 80% and des taux d'induction generalementeleves (80a90%).
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TL;DR: The N = 8 supergravity as mentioned in this paper is a work done in collaboration with B. Julia and S. Ferrara, who brought the trip through superspace in 11 dimensions under the direction of S Ferrara to return to ordinary 4 dimensional space-time.
Abstract: After the trip through superspace in 11 dimensions under the direction of S. Ferrara, 1 I am supposed to bring you back to ordinary 4 dimensional space-time by presenting to you the N = 8 supergravity, a work done in collaboration with B. Julia2.
TL;DR: Intracellular records were obtained from axons of second order vestibular neurons in, and around, the left abducens nucleus in alert cats implanted with stimulating electrodes on both Vestibular nerves and the left VIth nerve.
Abstract: Intracellular records were obtained from axons of second order vestibular neurons in, and around, the left abducens nucleus in alert cats implanted with stimulating electrodes on both vestibular nerves and the left VIth nerve. Twelve secondary vestibular neurons were identified by their increase in firing rate with horizontal head rotation to the left and/or increasing eye position to the right. Following HRP injection, somatic location, axonal trajectory and termination sites were determined. Each of the above cells collateralized extensively in the abducens nucleus in a fashion consistent with their being either inhibitory (n = 7; left) or excitatory (n = 6; right) vestibular neurons in the disynaptic horizontal vestibulo-ocular reflex pathway. These vestibular neurons also arborized extensively in other posterior brainstem eye-movement related areas as well as sending an axon to the spinal cord.
TL;DR: A new type of time correlation analysis of resonance fluorescence is presented in this paper, where a strontium atomic beam is excited by a 28-AA{}A-off-resonance laser.
Abstract: A new type of time correlation analysis of resonance fluorescence is presented. A strontium atomic beam is excited by a 28-\AA{}A-off-resonance laser. The photons of the two sidebands of the fluorescence triplet are shown to be emitted in a well-defined time order. A simple interpretation of this effect is given which implies a quantum jump of the atom from the lower to the upper state through a multiphoton process.
TL;DR: In this paper, the Wilson loop operator in quantum chromodynamics is interpreted as a string creation operator, and a method is developed to study its renormalization properties from the QCD Heisenberg equations of motion, which linearizes in a short-range approximation.
TL;DR: In this article, the superpartner of the massless spin-3 2 goldstino is axially coupled to leptons and quarks, and neutrino scattering experiments restrict its mass to less than 300 MeV/c2, approximately.
TL;DR: The existence of reliable and flexible FORTRAN programs for integer linear programming has recently enabled the development of very efficient algorithms for the travelling salesman problem, which can be used for the solution of the m-salesmen problem.
Abstract: The existence of reliable and flexible FORTRAN programs for integer linear programming has recently enabled the development of very efficient algorithms for the travelling salesman problem. The main characteristic of these algorithms is the relaxation of most of the constraints of the problem during its solution. The same approach can be used for the solution of the m-salesmen problem in which m salesmen starting from the same city must visit only once n cities at minimum cost. The number of salesmen can be fixed in advance or allowed to vary, upper and lower bounds set on the number of salesmen and even fixed costs associated with the salesmen. The results obtained so far are very encouraging. Problems of up to 100 cities have been solved optimally for the m-travelling salesmen case and other more complex problems are currently under study.
TL;DR: In this paper, the authors studied the quantitative determination and depth profiling of fluorine in the surface region of various substrates using nuclear reaction microanalysis, where different cross sections and excitation functions for the reaction 19 F(p, α 0 ) 16 O were investigated in great detail, especially in the vicinity of resonances.
TL;DR: In this article, the A 0 = 0 gauge formulation of Yang-Mills theories is discussed with the aid of the Feynman propagation kernel and the equivalence with the Coulomb-gauge formulation is proved.
TL;DR: In this paper, the authors performed experiments on the onset of turbulence in liquid 4He, as a function of the Prandtl number (0.4 Pr 0.8), for a series of cells of confined geometry with two convective rolls.
Abstract: 2014 We have performed experiments on the onset of turbulence in liquid 4He, as a function of the Prandtl number (0.4 Pr 0.8), for a series of cells of confined geometry with two convective rolls. For a low value of Pr the dynamic behaviour is similar to our previous studies, i.e. two frequencies followed by lock-in and subharmonic bifurcations of the lowest frequency, before the onset of turbulence. For high values of Pr a new frequency appears before onset of the Busse oscillatory instability. We associate this new regime with a change of the convective roll structure, perhaps due to the skewed varicose instability predicted by Busse, which gives a three dimensional character to the roll geometry. Various approaches to turbulence are then observed. In some cases the onset of turbulence is intermittent in time; in some others a regime with three frequencies exists before the onset of turbulence. All the results are strongly dependent on the roll wavenumber, in qualitative agreement with the Busse theory. J. Physique LETTRES 41 (1980) L-515 L-518
TL;DR: In this paper, a free-exciton gas is studied as a function of generated particle density in O at 1.5 K. A line-shape analysis of the subsequent recombination shows a gradual evolution, from a classical regime at low density, to a highly quantum-statistical one with chemical potential.
Abstract: A free-exciton gas is studied as a function of generated particle density in ${\mathrm{Cu}}_{2}$O at 1.5 K. A line-shape analysis of the subsequent recombination shows a gradual evolution, from a classical regime at low density, to a highly quantum-statistical one with chemical potential $\ensuremath{\mu}\ensuremath{\simeq}0$.
TL;DR: A new method for analyzing complex queueing networks is proposed: the isolation method, which studies packet switching networks with finite buffer size at each node.
Abstract: In this paper a new method for analyzing complex queueing networks is proposed: the isolation method. As an example, we study packet switching networks with finite buffer size at each node.
TL;DR: In this paper, a model of the V${\mathrm{O}}_{2}$ phase transition which incorporates both electron-electron and electron-lattice interactions and accounts for the presence of two $d$ bands overlapping at the Fermi level of the metallic phase is presented.
Abstract: We present a model of the V${\mathrm{O}}_{2}$ phase transition which incorporates both electron-electron and electron-lattice interactions and accounts for the presence of two $d$ bands (${\ensuremath{\pi}}^{*}$ and ${d}_{\ensuremath{\parallel}}$) overlapping at the Fermi level of the metallic phase. Attention is given to the crystallographic symmetry change at the transition and to the properties of the associated order parameter. To take into account electron-electron interaction, we use the functional-integral treatment of the Hubbard Hamiltonian. Then, to account for the electron-lattice interaction, the center of gravity and the shape of the $d$ bands are chosen so as to depend explicitly on the lattice distortion. Finally spin-spin interactions are described in terms of an Ising-like model. This treatment leads to a free energy expression which, at a given temperature, depends on two variational parameters: the mean amplitude of the local moment $\ensuremath{\mu}$ and the amplitude of the lattice distortion $\ensuremath{\eta}$. Minimization of the free energy with respect to $\ensuremath{\eta}$ and $\ensuremath{\mu}$ leads to the temperature dependence of these quantities. The transition which is a first-order one, appears to be driven by electron correlations which, below the transition temperature, stabilize a distorted phase with paired local magnetic moments on the vanadium sites and a density of states gap between the lower Hubbard ${d}_{\ensuremath{\parallel}}$ and the ${\ensuremath{\pi}}^{*}$ band. Our model lends itself to discussion of the magnetic susceptibility which, in the insulating phase, is governed by the pairing of the local magnetic moments, induced by the electron-lattice interaction. Using accepted values of the electronic structure parameters, we find a fairly quantitative agreement with experiment. We account for all the features of the ferroelastic, metal-insulator transition of V${\mathrm{O}}_{2}$.
TL;DR: This culture system seems to be very well suited for studies on the cellular regulation of the high molecular weight forms of AChE, and does not seem to be focally distributed on the surface of the myotubes.
01 Jan 1980
TL;DR: The bioconversions of nitriles and primary amides have a practical interest for the production of optically active α-hydroxy acids and for the preparation of highly pure amides and acids as mentioned in this paper.
Abstract: The bioconversions of nitriles and primary amides have a practical interest for the production of optically active α-hydroxy — or α-amino acids and for the preparation of highly pure amides and acids. The appropriate chemical hydrolyses are generally not suitable for such syntheses.
TL;DR: It is demonstrated that, in T28 stationary cells, the cellular G4 form is associated with the plasma membrane, whereas the G1 form is intracellular, suggesting, in agreement with previous observations, that GI is a metabolic precursor of G4.
Abstract: Studies were carried out on the polymorphism of acetylcholinesterase (AChE, EC 3.1.1.7) in a neuroblastoma x sympathetic ganglion cell hybrid cell line (T28) and its parental clone (N18TG2). These cells contain the tetrameric (G4, 10S), dimeric (G2, 6.5S) and monomeric (G1, 4S) forms of AchE, but not the collagen-tailed A12(16S) form of the sympathetic ganglion. Three variants of these forms could be distinguished on the basis of their solubility properties: (i) secreted forms which do not interact with the detergent Triton X-100; (ii) cellular forms which may be solubilized in detergent-free buffer and which interact reversibly with Triton X-100; (iii) cellular forms which require detergent for solubility, and aggregate in its absence. By using a nonpenetrating inhibitor, we demonstrated that, in T28 stationary cells, the cellular G4 form is associated with the plasma membrane, whereas the G1 form is intracellular. During induction of AChE activity in T28 cells, the relative proportion of the G4 form increases, suggesting, in agreement with previous observations, that G1 is a metabolic precursor of G4. The evolution of AChE molecular forms released into the culture medium closely resembles that of the cellular forms. The preferential accumulation of the G4 molecules does not simply depend on the cellular level of G1. It is favoured by culture conditions which promote morphological differentiation, but does not require the actual extension of neurites. T28 cells as well as other neuroblastoma-derived cells appear to be useful experimental materials to investigate the regulatory mechanisms underlying the maturation of AChE globular forms.
TL;DR: In this paper, the conditions for the formation of core-shell structures for triblock copolymers Cop A-B-C, having three sequences of different types, in this case, poly(styrene-b-isoprene)-b-methyl methacrylate, were given.
Abstract: New morphologies, especially “core-shell” and multilayered structures (“onion structure”) have been obtained for polymer blends containing block copolymers. For triblock copolymers Cop A-B-C, having three sequences of different types, in this case, poly(styrene-b-isoprene-b-methyl methacrylate), the conditions are given for the formation of core-shell structures. A scheme is presented showing the structures of the mesomorphic phases, as a function of the composition of the copolymer. Multilayered and core-shell structures have also been obtained by a suitable combination of two diblock copolymers, Cop A-B, i.e., poly(styrene-b-isoprene), with a corresponding homopolymer, i. e., polystyrene. One of the copolymers can act as an emulsifier for the second one forming the dispersed phase of the blend. An extension of the classical mesomorphic structures is presented, and it is shown that the emulsifying effect of block copolymers is quite general.
TL;DR: HAL as mentioned in this paper is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not, which may come from teaching and research institutions in France or abroad, or from public or private research centers.
Abstract: HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. UNE EXPERIENCE DE RAYLEIGH-BENARD DE GEOMETRIE REDUITE ; MULTIPLICATION, ACCROCHAGE ET DEMULTIPLICATION DE FREQUENCES A. Libchaber, J. Maurer
TL;DR: In this article, the authors studied the asymptotic behavior of the charge fluctuations in infinite classical systems of charged particles, and showed that if the fluctuations are not extensive, then they are necessarily of the order of the surface.
Abstract: We study the asymptotic behavior of the charge fluctuations 〈(Q
Λ − 〈(Q
Λ〉)2〉 in infinite classical systems of charged particles, and show, under certain clustering assumptions, that if the charge fluctuations are not extensive, then they are necessarily of the order of the surface ¦∂λ¦. Moreover, when the canonical sum rules that are typical for equilibrium states of particles interacting with long-range forces hold true, we prove a central limit theorem for the normalized charge variable ¦∂λ¦−1/2(〈(Q
Λ − 〈(Q
Λ〉)) in two and three dimensions. In one dimension, the probability distribution of the charge itself converges. The latter case is illustrated by the example of the one-dimensional Coulomb gas.