Showing papers by "Centre national de la recherche scientifique published in 1984"
TL;DR: In this article, a metallic solid with long-range orientational order, but with icosahedral point group symmetry, which is inconsistent with lattice translations, was observed and its diffraction spots are as sharp as those of crystals but cannot be indexed to any Bravais lattice.
Abstract: We have observed a metallic solid (Al-14-at.%-Mn) with long-range orientational order, but with icosahedral point group symmetry, which is inconsistent with lattice translations. Its diffraction spots are as sharp as those of crystals but cannot be indexed to any Bravais lattice. The solid is metastable and forms from the melt by a first-order transition.
5,702 citations
TL;DR: In this paper, the authors present a different representation, in which frequency shifts are replaced by dilations, and the resulting "voice transform" and "cycle-octave transform" are briefly described from the mathematical point of view and illustrated by numerical examples.
1,352 citations
TL;DR: A general formalism for the description of configurational cluster functions in multicomponent systems is developed and a new interpretation of the Cluster Variation Method as a self-consistency relation on the renormalized cluster energies is presented.
Abstract: A general formalism for the description of configurational cluster functions in multicomponent systems is developed. The approach is based on the description of configurational cluster functions in terms of an orthogonal basis in the multidimensional space of discrete spin variables. The formalism is used to characterize the reduced density matrices (or cluster probability densities) and the free energy functional obtained in the Cluster Variation Method approximation. For the particular representation chosen, the expectation values of the base functions are the commonly used multisite correlation functions. The latter form an independent set of variational parameters for the free energy which, in general, facilitates the minimization procedure. A new interpretation of the Cluster Variation Method as a self-consistency relation on the renormalized cluster energies is also presented.
1,341 citations
TL;DR: In this paper, moments of the velocity structure function up to the eighteenth order were calculated, primarily with a view to establish accurately the dependence on the order of the inertial range power-law exponent and to draw conclusions about the distribution of energy transfer in the Inertial range.
Abstract: Measurements are presented of the velocity structure function on the axis of a turbulent jet at Reynolds numbers Rλ ≤ 852 and in a turbulent duct flow at Rλ = 515. Moments of the structure function up to the eighteenth order were calculated, primarily with a view to establish accurately the dependence on the order of the inertial range power-law exponent and to draw conclusions about the distribution of energy transfer in the inertial range. Adequate definition of the probability density of the structure function was achieved only for moments of order n ≤ 10. It is shown, however, that, although the values of moments of n > 10 diverges from their true values, the dependence of the moment of the structure function on the separation r is still given to a fair accuracy for moments up to n ≈ 18. The results demonstrate that the inertial-range power-law exponent is closely approximated by a quadratic dependence on the power which for lower-order moments (n [lsim ] 12) would be consistent with a lognormal distribution. Higher-order moments diverge, however, from a lognormal distribution, which gives weight to Mandelbrot's (1971) conjecture that ‘Kolmogorov's third hypothesis’ is untenable in the strict sense. The intermittency parameter μ, appearing in the power-law exponent, has been determined from sixth-order moments 〈(δμ)6〉 ∼ r2−μ to be μ = 0.2 ± 0.05. This value coincides with that determined from non-centred dissipation correlations measured in identical conditions.
934 citations
TL;DR: An early rebound (before 5.5 yr) is followed by a significantly higher adiposity level than a later rebound (after 7 yr), which is observed whatever the subject's adiposity at 1 yr.
882 citations
TL;DR: In this paper, the Hartree-Fock-Bogolyubov theory of nuclei in the coordinate representation is considered and the HFB equation for the Skyrme effective interaction is solved.
723 citations
TL;DR: In this paper, the general coupling of nN = 2 Maxwell super-multiplets to N = 2 supergravity in five spacetime dimensions was constructed. But the authors only considered the case that the scalar field manifold is symmetric.
720 citations
TL;DR: Coesite was reported for the first time from the Caledonide orogen as discussed by the authors, and it occurs as inclusions in clinopyroxene in the dolomite-eclogite at Grytting, Norway, and provides valuable new evidence to support the hypothesis of extremely high pressure in certain Norwegian eclogites.
Abstract: Coesite is reported for the first time from the Caledonide orogen. It occurs as inclusions in clinopyroxene in the dolomite-eclogite at Grytting, Norway, and provides valuable new evidence to support the hypothesis of extremely high pressure (≥30 kbar) in certain Norwegian eclogites. This finding has implications for the geodynamics and kinetics of the concepts of microscale intracrystalline tectonic overpressure and of macroscale local or regional tectonic overpressure, and for the hypotheses of subduction and obduction involving a more than 100km vertical component of transport.
706 citations
TL;DR: In this paper, a review of recent electron microscope observations relating to the carbonization and graphitization of a variety of carbonaceous precursors is made and the different behaviors of graphitizing and non-graphitizing carbons are elucidated, and the effect of sulphur as a crosslinker is determined.
666 citations
TL;DR: Palynology provides information about Pliocene and early Pleistocene vegetation and climate evolution in the north-west Mediterranean area in relation to high northern latitude climatic trends as mentioned in this paper.
Abstract: Palynology provides information about Pliocene and early Pleistocene vegetation and climate evolution inthe north-west Mediterranean area in relation to high northern latitude climatic trends. An important change occurred approximately 3.2 Myr ago with the appearance of the Mediterranean climatic rhythm (summer drought) causing the individualization of the modern Mediterranean floral elements. Quaternary-type mediterranean climatic fluctuations started approximately 2.3 Myr ago (early Glacial) causing the Mediterranean-type of vegetational organization.
651 citations
TL;DR: The changes in women's position are related to their role in production, social status in the place of origin, employment opportunities in the receiving areas for men as well as women, and finally, migration patterns and reasons for migration.
Abstract: Migrant women from poor countries represent a labor supply which is at once the most vulnerable flexible and at least in the beginning the least demanding. They are incorporated into sexually segregated labor markets at the lowest stratum in high-tech industries or at the cheapest sectors in labor intensive industries. They bear the brunt of the ideology of racism and an insecure political and legal status as all migrants do which along with gender discrimination and class exploitation contribute to their vulnerability. For instance after the 1974 halt on further labor immigration the Western European receiving countries imposed either a complete ban or waiting periods for entry into the labor market for the spouces who joined migrants already in these countries. This regulation concerned non-EEC citizens mostly women. In the absence of legitimate employment opportunities these women turned to illegal employment. For employers there are obvious advantages in hiring illegal labor--tax violation flexibility and non-application of labor legislation. Legally these women are defined as dependents in keeping with the Western ideology where man is the breadwinner whether this dependency is real or not. Thus there stay is linked to the legal status of their migrant husbands. The work of native and migrant women do not always conform to the prevailing definition of work and therefore not often recognized as an economic activity in data collection. In the process of migration and incorporation into waged employment women may experience either increased exploitation or may gain greater independence and an awareness that their situation can be changed. The changes in womens position are a function of the socioeconomic and cultural context in which they take place and are related to their role in production social status in the place of origin employment opportunities in the receiving areas for men as well as women and finally migration patterns and reasons for migration. Migration tends to be treated as a phenomenon involving young males seeking economic betterment. There is need for better understanding of migration of women.
TL;DR: The complete nucleotide sequence of the mouse 28S rRNA gene is determined and it is indicated that the potential for major variations in size during the evolution has been restricted to a unique set of a few sites within a largely conserved secondary structure core.
Abstract: We have determined the complete nucleotide sequence (4712 nucleotides) of the mouse 28S rRNA gene. Comparison with all other homologs indicates that the potential for major variations in size during the evolution has been restricted to a unique set of a few sites within a largely conserved secondary structure core. The D (divergent) domains, responsible for the large increase in size of the molecule from procaryotes to higher eukaryotes, represent half the mouse 28S rRNA length. They show a clear potential to form self-contained secondary structures. Their high GC content in vertebrates is correlated with the folding of very long stable stems. Their comparison with the two other vertebrates, xenopus and rat, reveals an history of repeated insertions and deletions. During the evolution of vertebrates, insertion or deletion of new sequence tracts preferentially takes place in the subareas of D domains where the more recently fixed insertions/deletions were located in the ancestor sequence. These D domains appear closely related to the transcribed spacers of rRNA precursor but a sizable fraction displays a much slower rate of sequence variation.
TL;DR: Most continuous antigenic determinants of tobacco mosaic virus protein, myoglobin and lysozyme correspond to those surface regions in the protein structure, as determined by X-ray crystallography, which possess a run of high-temperature factors along the polypeptide backbone, that is, a high segmental mobility.
Abstract: Most continuous antigenic determinants of tobacco mosaic virus protein (TMVP), myoglobin and lysozyme correspond to those surface regions in the protein structure, as determined by X-ray crystallography, which possess a run of high-temperature factors along the polypeptide backbone, that is, a high segmental mobility. The mobility of an antigenic determinant may make it easier to adjust to a pre-existing antibody site not fashioned to fit the exact geometry of a protein. The correlation found between temperature factors and antigenicity is better than that between hydrophilicity and antigenicity.
TL;DR: The complete amino acid sequence (703 amino acid residues) of human lactotransferrin has been determined and prediction of the secondary structure of the two homologous moieties of human dairy product has been performed.
Abstract: The complete amino acid sequence (703 amino acid residues) of human lactotransferrin has been determined. The location of the disulfide bridges has also been investigated. Computer analysis established internal homology of the two domains (residues 1 - 338 and residues 339 - 703). Each domain contains a single iron-binding site and a single glycosylation site (asparagine residues 137 and 490) located in homologous positions. Prediction of the secondary structure of the two homologous moieties of human lactotransferrin has also been performed. The present results allowed a series of comparisons to be made with human serum transferrin and hen ovotransferrin.
TL;DR: Experimental evidence and speculation relative to chemical messages exchanged by Drosophila during courtship and mating are reviewed, and emphasis is put on female aphrodisiacs, as they clearly participate in sex and species recognition.
Abstract: Experimental evidence and speculation relative to chemical messages exchanged byDrosophila during courtship and mating are reviewed. Only the speciesD. melanogaster andD. simulans are considered in detail. Emphasis is put on female aphrodisiacs, as they clearly participate in sex and species recognition. All the aphrodisiac molecules described are unsaturated long-chain hydrocarbons, and position 7 for a double bond seems important in both species. InD. melanogaster, only females are able to make 7,11-dienes, compounds which stimulate males of this species to court. InD. simulans, 7-tricosene plays a similar role but is produced by both sexes as well as maleD. melanogaster. In both species, polymorphism is shown for these molecules. Their biosynthesis is also considered and both preliminary biochemical and genetic data are introduced. Male-specific compounds which regulate male and female behaviors are also reviewed. For example,cis-vaccenyl acetate inhibits male courtship; one or two peptides control the female's receptivity and egg laying. Such compounds are transferred from males to females together with sperm.
TL;DR: In this article, a review examines recent developments in the use of life stories (i.e., oral, autobiographical narratives), placing particular emphasis on work done in continental Europe.
Abstract: This review examines recent developments in the use of life stories (i.e. oral, autobiographical narratives), placing particular emphasis on work done in continental Europe. Two main trends are identified. The first focuses primarily upon the symbolic in social life and meaning in individual lives. Ways of collecting and analyzing life stories within this perspective (e.g. the narrative interview, objective hermeneutics) are described. The second main trend considers interviewees as informants-in ethnographic fashion. The aim is to get accurate descriptions of the interviewees' life trajectories in social contexts, in order to uncover the patterns of social relations and the special processes that shaped them. The emphasis here is on comparison, on searching for negative cases, and on reaching the point of saturation whereby the sociologist's mental representation of given patterns may be generalized to a whole social milieu. The first trend is now developing faster in Germany and the Anglo-Saxon countries, while the second attracts more attention in the Latin countries of Europe and America. Because life stories are put to multiple uses, no standard methodology is expected to appear in the near future. But several well-tested ways of collecting, analyzing, and publishing life stories should emerge. Life stories are shown to be a rich ground for the formulation of substantive theories, which are conceived of as interpretations rather than as scientific explanations. Different ways of assessing the validity of interpretations are mentioned. Work done with
TL;DR: It appears that the interactions between calcium ions and cell walls play a key role in plant physiology and calcium can significantly affect this factor, the density of non-diffusible charges.
Abstract: . From this brief review it appears that the interactions between calcium ions and cell walls play a key role in plant physiology. Calcium ions are involved in many mechnisms: for example, stabilization of cell wall structures, acidic growth, ion exchange properties, control of the activities of wall enzymes. All these properties originate from the tight binding of calcium ions to the pectins present in the cell walls. The factor most important for controlling wall behaviour is the density of non-diffusible charges and, due to its high affinity, calcium can significantly affect this factor. We also discuss the theoretical ion exchange models in relation to the specific role of calcium ions.
TL;DR: In this article, the authors give the solution of the inverse problem in seismic exploration using the Kirchhoff migration and the circle summation model, which can be obtained using an iterative algorithm.
Abstract: This is the first of a series of papers giving the solution of the inverse problem in seismic exploration. The acoustic approximation is used together with the assumption that the velocity field has the form
. The forward problem is then linearized (thus neglecting multiple reflected waves) and the inverse problem of estimating δ is set up. Its rigorous solution can be obtained using an iterative algorithm, each step consisting of a classical Kirchhoff migration (hyperbola summation) plus a classical forward modeling step (circle summation).
TL;DR: In this paper, a system of spins with quenched random mfimte ranged p-spin interactions for p -* co is studied and the model is solved exactly either by a direct mlcrocanomcal argument, or through the introduction of rephcas and Pansl's ultrametnc ansatz for symmetry breaking, or by means of TAP mean field equat,ons.
TL;DR: The final effort of the CLIMAP project was a study of the last interglaciation, a time of minimum ice volume some 122,000 yr ago coincident with the Substage 5e oxygen isotopic minimum.
TL;DR: In this paper, the authors compared the 13C/12C ratios of Upper Holocene benthic foraminiferal tests (genera Cibicides and Uvigerina) of deep sea cores from various world ocean basins.
TL;DR: Using the correlogram and variance spectral density, the time series of rainfall and discharge of a hydrological system are analysed in a descriptive way differing from the traditional method as discussed by the authors.
01 Jan 1984
TL;DR: A systematic method for the design of systolic arrays that may be used for algorithms that can be expressed as a set of uniform recurrent equations over a convex set D of Cartesian coordinates.
Abstract: We describe a systematic method for the design of systolic arrays. This method may be used for algorithms that can be expressed as a set of uniform recurrent equations over a convex set D of Cartesian coordinates. Most of the algorithms already considered for systolic implementation may be represented in this way. The methods consists of two steps: finding a timing-function for the computations that is compatible with the dependences introduced by the equations, then mapping the domain D onto another finite set of coordinates, each representing a processor of the systolic array, in such a way that concurrent computations are mapped onto different processors. The scheduling and mapping functions meet conditions that allow the full automation of the method. The method is exemplified on the convolution product and the matrix product.
TL;DR: In this article, the role of surface forces on deformation and adherence of metal microcontacts is reviewed and the condition of existence of each mode as a function of the five parameters involved (Young's modulus, elastic limit, surface energy, radius of curvature and load).
TL;DR: In this article, a compilation of working values and sample description for 170 international reference samples of mainly silicate rocks end minerals is presented, with 14 pages for the main text and 73 pages for four appendices.
Abstract: 1984 compilation of working values and sample description for 170 international reference samples of mainly silicate rocks end minerals.
Working values and sample description for 170 international rock and mineral reference samples are presented in B7 pages, with 14 pages for the main text and 73 pages for the four appendices. Appendix I presents working values for 170 reference samples in 19 pages, each page containing data on 10 samples, in general. Data on each sample are given in five colored blocks, the first block for 15 major and minor elements and the other four for 66 trace elements, whenever such data were available. Working values for each element are arranged, in ascending order, in Appendix II (39 pages). Brief sample description of each sample (numbered 001 to 170) and References form respectively Appendix III and IV. This compilation is published as a special issue of Geostandards Newsletter (July 19841, with the financial support of UNESCO and the International Association of Geochemistry and Cosmochemistry.
RESUME
Compilation (1984) des valeurs de travail et la description dea echantillms pour 170 echantillms internationaux de reference principalement des roches silicatees et des mineraux.
Des valeurs de travail (“working values”) et la description des echantillons pour 170 echantillons internationaux de roches et mineraux sont presentes dens 87 pages avec 14 pages pour le texte principal et 73 pages pour les quatre annexes. L'Annexe I contient des valeurs de travail pour 170 echantillons de reference reparties sup 19 pages, avec cheque page en generale, contenent des donnees sup dix echantillons. Les donnees sur cheque echantillon sont consignees dens cinq blocs colories, le premier bloc pour 15 elements majeurs et mineurs et les quatre autres pour 66 elements en traces. Lea valeurs de travail pour cheque element sont presentees, dens l'ordre ascendant, dens 1'Annexe II (39 pages). Une description breve dc cheque echantillon, numerote de 001 a 170, et les References forment respectivement 1'Annexe III et IV. Cette compilation est publiee comme un numero special du Geostandards Newsletter (Juillet 1984), avec le concours financier de l'UNESCO et l'Association Internationale de la Geochimie et Cosmochimie.
TL;DR: In this paper, a tripartite molecule with a long-lived photodriven charge-separated state of relatively high potential is formed from an excited singlet state in accordance with the above principles.
Abstract: The key steps in the photosynthetic conversion of light to chemical potential energy include not only photodriven charge separation, but also prevention of the back-reaction (charge recombination). Although the first of these steps has been achieved in several biomimetic solar energy conversion systems, retarding the back-reaction has proved more difficult. This may be accomplished by rapidly moving the electron, the hole, or both away from the site of excitation to more stabilizing environments. In photosynthetic membranes, the electron is transferred sequentially over several closely coupled molecules, including tetrapyrroles and quinones1–3. In semiconductor/liquid interfacial systems both the electron and the hole migrate following excitation4,5. We now report that substantial slowing of the back-reaction has been achieved with a tripartite molecule in which a long-lived photodriven charge-separated state of relatively high potential is formed from an excited singlet state in accordance with the above principles. This molecular triad (compound I) consists of a tetraarylporphyrin covalently linked to both a carotenoid and a quinone. In solution, excitation of the porphyrin moiety by visible light results in the rapid (<100 ps) formation of a transient species C+.−P−Q−−., with a lifetime on the μs time scale and an energy more than 1 eV above the ground state.
TL;DR: The pattern of similarities between these odorants, as delineated with the aid of correlation coefficient computation, factor analysis and non-hierarchical taxonomy, confirms the reality of several odorant groups previously suggested and describes their cross-relationships.
TL;DR: In this article, the kinetics of the p-benzoquinone/hydroquinone Q/QH2 couple on a platinum electrode were analysed on the basis of the theory presented earlier (E Laviron, J Electroanal Chem, 146 (1983) 15) for the nine-member square scheme when the protonations are assumed to be at equilibrium.
TL;DR: DNA sequences of four human class II histocompatibility antigen α chain DNA sequences are presented and compared to DRα and to mouse I-Aα and I-Eα sequences, suggesting possible mechanisms for the generation of polymorphism and the evolution of the DR, DC and SB families.
Abstract: DNA sequences of four human class II histocompatibility antigen alpha chain DNA sequences (derived from cDNA and genomic clones representing DC1 alpha, DC4 alpha, DX alpha and SB alpha) are presented and compared to DR alpha and to mouse I-A alpha and I-E alpha sequences. These data suggest possible mechanisms for the generation of polymorphism and the evolution of the DR, DC and SB families.
TL;DR: The serological cross-reactivity between Y. enterocolitica serotype O:9 and the lipopolysaccharides of Vibrio cholerae and Brucella species can now be related to the presence of N-acylated 4-amino-4,6-dideoxy-alpha-D-mannopyranosyl residues in their respective O-antigenic chains.
Abstract: The phenol-phase soluble cellular lipopolysaccharide isolated by the phenol/water extraction method from Yersinia enterocolitica serotype O:9 cells was shown by hydrolytic, periodate oxidation, methylation and nuclear magnetic resonance studies to be an S-type lipopolysaccharide with a linear O-antigenic polysaccharide of 1,2-linked 4,6-dideoxy-4-formamido-alpha-D-mannopyranosyl units. The serological cross-reactivity between Y. enterocolitica serotype O:9 and the lipopolysaccharides of Vibrio cholerae and Brucella species can now be related to the presence of N-acylated 4-amino-4,6-dideoxy-alpha-D-mannopyranosyl residues in their respective O-antigenic chains.