A tabu thresholding algorithm for arc crossing minimization in bipartite graphs

1996

Acyclic directed graphs are commonly used to model complex systems. The most important criterion to obtain a readable map of an acyclic graph is that of minimizing the number of arc crossings. In this paper, we present a heuristic for solving the problem of minimizing the number of arc crossings in a bipartite graph. It consists of a novel and easier implementation of fundamental tabu search ideas without explicit use of memory structures (a tabu thresholding approach). Computational results are reported on a set of 250 randomly generated test problems. Our algorithm has been compared with the two best heuristics published in the literature and with the optimal solutions for the test proble…

Novel acrylamido monomers with higher hydrophilicity and improved hydrolytic stability: III. DNA separations by capillary electrophoresis in poly(N-a…

1996

Separation of DNA fragments in a novel polymer network, consisting of N-acryloylaminopropanol (AAP) is reported. The performance of this novel monomer, as a sieving liquid polymer in capillary zone electrophoresis, was evaluated. In 50 microns ID capillaries, an 8% solution of poly (AAP) can afford apex-resolution of the 123/124 bp adjacent pair of DNA fragments in marker V, typically unresolved in any poly (acrylamide) formulation. It is proposed that the distal-OH group in the AAP molecule can form transient H-bonds with the DNA double helix. Molecular modeling shows a meandering structure for poly (AAP), lacing the walls of half a cylinder, with kinks protruding at regular intervals, pot…

High Resolution Mass Spectrometry of Light Ions in a Penning Trap

1996

Longitudinal contribution to the alignment polarization of quarks produced in e + e - -annihilation: an O (α s ) effect

1996

We calculate the longitudinal contribution to the alignment polarization Pl of quarks produced in e+e− annihilation. In the Standard Model, the longitudinal alignment polarization vanishes at the Born term level and thus receives its first non-zero contribution from the O(αs) tree graph process. We provide analytical and numerical results for the longitudinal alignment polarization of massless and massive quarks, in particular for the recently discovered top quark.

Les modèles météorologiques de méso-échelle

1996

National audience

Static freezing transition at a finite temperature in a quasi-one-dimensional deuteron glass.

1996

The dipolar freezing process of a quasi-one-dimensional betaine deuteron glass was studied using linear and nonlinear dielectric spectroscopy. The linear response as measured for frequencies $5\mathrm{mHz}l\ensuremath{\nu}l200\mathrm{MHz}$ was analyzed using the recently invented $\ensuremath{\delta}$ plot, providing evidence for a static freezing transition near 30 K. Measurements of the ergodic to nonergodic transition as well as of the incipient divergence of the nonlinear susceptibility yield independent confirmation of this quasistatic freezing transition temperature. The critical exponent describing the nonlinear behavior is found to be $\ensuremath{\gamma}\phantom{\rule{0ex}{0ex}}=\p…

Estimation des flux de surface à l'échelle régionale

1996

National audience

Spontaneous breakdown of CP in left-right symmetric models

1996

We show that it is possible to obtain spontaneous CP violation in the minimal $SU(2)_L \times SU(2)_R \times U(1)_{B-L}$, i.e. in a left right symmetric model containing a bidoublet and two triplets in the scalar sector. For this to be a natural scenario, the non-diagonal quartic couplings between the two scalar triplets and the bidoublet play a fundamental role. We analyze the corresponding Higgs spectrum, the suppression of FCNC's and the manifestation of the spontaneous CP phase in the electric dipole moment of the electron.

Magnetic Field-Induced Fano Profiles in the Absorption Coefficient of Semiconductors

1996

A strongly asymmetric, Fano-like resonance profile has been found for magneto-absorption in the states of hot free electron-hole pairs scattered by defects in bulk semiconductors. The renormalization of the absorption profile, compared to that expected from the bare density of states in a high magnetic field, follows from a quasi-one-dimensional character of electronic excitations. The results are valid for absorption by the electronic states of large Landau quantum number where the Coulomb interaction should play a minor role. The resonance shape is in a good qualitattive agreement with experimental observations.

The structure and phase transition of tris(n-propylammonium) enneachlorodiantimonate (III),

1996

The crystal structure of at 298 K has been determined (monoclinic, space group Cc, a = 19.464(2) ?, b = 17.736(2) ?, c = 8.116(2) ?, , Z = 4). The structure consists of one-dimensional polyanionic chains extended along the c-axis, and n-propylammonium cations located in elongated cavities formed by polyanions. The cations are connected to chlorine atoms by hydrogen bonds. Differential scanning calorimetry, the temperature dependence of the lattice parameters and static electric permittivity studies revealed a first-order phase transition at K of an `order - disorder' type. It is related to the ordering of n-propylammonium cations that occurs on decreasing the temperature. Debye-like dispers…

Purification and characterisation of a plasmin-sensitive surface protein of Staphylococcus aureus.

1996

Certain methicillin-resistant Staphylococcus aureus strains contain a 230-kDa cell-wall protein which is not present on the surface of other staphylococci. The presence of this 230-kDa protein is associated with a negative test result in commercial assays designed to detect fibrinogen-binding proteins and/or protein A on the staphylococcal surface. We have purified and partially characterised the 230-kDa protein from a lysostaphin digest of a non-agglutinating methicillin-resistant S. aureus strain. Partial amino acid sequence data obtained from the purified protein did not reveal any significant similarities to known proteins which indicates that the protein is novel. The 230-kDa protein w…

Amino acid substitutions enhancing thermostability of Bacillus polymyxa beta-glucosidase A

1996

Mutations enhancing the thermostability of β-glucosidase A of Bacillus polymyxa, a family 1 glycosyl hydrolase, have been obtained after hydroxylamine mutagenesis of a plasmid containing the bglA gene, transformation of Escherichia coli with the mutagenized plasmid, and identification of transformant colonies that showed β-glucosidase activity after a thermal treatment that inactivated the wild-type enzyme. Two additive mutations have been characterized that cause replacement of glutamate at position 96 by lysine and of methionine at position 416 by isoleucine respectively. The thermoresistant mutant enzymes showed increased resistance to other denaturing agents, such as pH and urea, while …

Réserve de propriété. Plan de cession englobant un bien vendu avec réserve de propriété, Engagement du cessionnaire de faire son affaire personnelle …

1996

International audience; (Com. 17 mai 1994, SECI c/ Creusot-Loire et autre).

Action en responsabilité exercée par le représentant des créanciers. Action en réparation du préjudice collectif des créanciers, Compensation des dom…

1996

International audience; (Com. 28 mars 1995, Naudin et a. c/ Soc Case Poclain)

The application of the photoacoustic transmittance oscillations for determining elastic constants in gallium and indium selenides

1996

Transmittance periodic oscillations are observed in GaSe and InSe on excitation with optical pulses. Such oscillations are explained in terms of photoacoustic generation of dilatational waves, which become resonant within the crystal. Spectral analysis of those oscillations in samples of different thickness has led to an accurate determination of the longitudinal acoustic‐wave velocity along the crystallographic axis c. Julio.Pellicer@uv.es ; Chantal.Ferrer@uv.es ; Vicente.Munoz@uv.es

Article 40. Créance née entre le jugement arrêtant le plan de cession et la liquidation judiciaire consécutive à la résolution du plan de cession, Or…

1996

International audience; (Com. 6 déc. 1994, Guyot ès qual. c/ Banque Paribas)

Déclaration et vérification des créances. Extinction de la créance pour forclusion. Exception opposable par le donneur d'aval (oui)

1996

International audience; (Com. 25 oct. 1994, URSSAF de Montreuil c/ Babinard et autre)

Déclaration et vérification des créances. Relevé de forclusion, Irrecevabilité de l'appel-nullité du débiteur dessaisi

1996

International audience; (Com. 14 mars 1995, Mme Saada c/ Caisse de crédit mutuel des professionnel de santé de Provence ; Com. 28 juin 1994, Guinne c/ Soc. Noblier)

Human HepG2 and rat Fao hepatic-derived cell lines show different responses to ciprofibrate, a peroxisome proliferator: analysis by flow cytometry.

1996

Abstract Peroxisome proliferators, and especially hypolipidemic drugs such as ciprofibrate, are known to be hepatocarcinogens in rodents, but their effect in humans is controversial. In an attempt to investigate the effects of ciprofibrate at a cellular level, the analysis of individual whole cells was performed by flow cytometry on samples from two hepatic-derived cell lines: the rat Fao cell line and the human HepG2 cell line. The increase of light scatter signals in rat Fao cells treated for 3 days with ciprofibrate at 250 μMwas related to modifications of intrinsic cellular parameters, such as size and cytoplasmic granularity. Conversely, no variations appeared in human HepG2-treated ce…

Purification and Characterization of the Soluble Interleukin-6 Receptor from Human Plasma and Identification of An Isoform Generated through Alternat…

1996

The soluble human interleukin-6 receptor (shIL6R) was purified from human plasma. In a single immunoaffinity purification step a 140000-fold enrichment with a yield of 95% was achieved. A subsequent IL-6 affinity chromatography resulted in a homogeneous receptor preparation but only in a yield of less than 5%. The biological activity of the soluble receptor was clearly demonstrated by its ability to induce the synthesis of the acute-phase protein α1-antichymotrypsin in HepG2 cells stably transfected with IL-6. Upon gel filtration, the native shIL6R showed an apparent molecular mass of 93 kDa. Analysis by SDS/PAGE revealed an apparent molecular mass of 65 kDa for the soluble receptor. Deglyc…

In murine 3T3 fibroblasts, different second messenger pathways resulting in the induction of NO synthase II (iNOS) converge in the activation of tran…

1996

Transcription factor NF-kappaB is essential for the induction of nitric oxide synthase (NOS) II (iNOS) by bacterial lipopolysaccharide in murine macrophages (Xie, Q. W., Kashiwabara, Y., and Nathan, C. (1994) J. Biol. Chem. 269, 4705-4708). In 3T3 fibroblasts, agents other than cytokines are efficacious inducers of NOS II expression. In addition to cytokines such as interferon-gamma or tumor necrosis factor-alpha, protein kinase C-stimulating agents such as tetradecanoylphorbol-13-acetate, or cyclic AMP-elevating agents such as forskolin and 8-bromo-cAMP markedly increased NOS II mRNA (measured by Sl nuclease and RNase protection analyses), NOS II protein (determined by Western blotting), a…

Interstitial-oxygen-atom diffusion in MgO.

1996

configuration is the ~111! dumbbell centered at a regular oxygen site, whereas face-centered and cube-centered configurations are higher in energy by 1.45 eV and 3.57 eV, respectively. The~111! configuration isclose in energy to the ~110! configuration, which allows the dumbbell to rotate easily on a lattice site. In allthese four cases the interstitial oxygen atom attracts considerable additional electron density from its nearestregular O

The integral‐direct coupled cluster singles and doubles model

1996

An efficient and highly vectorized implementation of the coupled cluster singles and doubles (CCSD) model using a direct atomic integral technique is presented. The minimal number of n6processes has been implemented for the most time consuming terms and point group symmetry is used to further reduce operation counts and memory requirements. The significantly increased application range of the CCSD method is illustrated with sample calculations on several systems with more than 500 basis functions. Furthermore, we present the basic trends of an open ended algorithm and discuss the use of integral prescreening. © 1996 American Institute of Physics.

Optical properties of silver halide fibres: ageing effects

1996

The relation between the structure of fibres extruded from mixed silver halides and their IR optical losses and luminescence properties is studied. The recently established ageing effect of the considerable growth of mean grain size of the fibre's polycrystalline structure (typically from 20 to 1000 nm in two years) is correlated with IR and luminescence measurements. IR spectra measured in the interval show growth of the concentrations of molecular impurities. The luminescence measurements are used for the characterization of the fibre's structure ordering. The luminescence decay kinetics is analysed theoretically in terms of the diffusion-controlled recombination of spatially well-correla…

Measures of the galaxy clustering

1996

A brief introduction is given to some aspects of the statistical description of the luminous matter distribution. I review the features of the redshift surveys that arise in the statistical analysis of the galaxy clustering. Special topics include intensity functions, correlation functions, correlation integrals, multifractals and multiscaling.

Multiscaling

1996

We introduce the unbiased way statisticians look at the 2--point correlation function and study its relation to multifractal analysis. We apply this method to a simulation of the distribution of galaxy clusters in order to check the dependence of the correlation dimension on the cluster richness.

Precise lifetime determination of the metastable 3d 2 D 5/2 level in Ca + by "electron shelving"

1996

Ca+ ions confined as a cloud in a Paul trap were excited and cooled by radiation from two lasers, tuned to the 4s2S1/2 − 4p2P1/2 and 4p2P1/2 − 3d2D3/2 transitions. The strong fluorescence of these lines disappears when we excite the ions simultaneously by a third laser on the 3d2D3/2 − 4p2P3/2 line because of population trapping in the metastable 3d2D5/2 state, into which the 4p2P3/2 level decays. From the time dependence of the fluorescence after blocking the third laser we determined the lifetime of the 3d2D5/2 level. Our result of τ = 1064(17) ms improves earlier results and agrees with the value recently computed by Liaw using the Brueckner approximation.

Friedreich's Ataxia: Autosomal Recessive Disease Caused by an Intronic GAA Triplet Repeat Expansion

1996

International audience; Friedreich's ataxia (FRDA) is an autosomal recessive, degenerative disease that involves the central and peripheral nervous systems and the heart. A gene, X25, was identified in the critical region for the FRDA locus on chromosome 9q13. This gene encodes a 210-amino acid protein, frataxin, that has homologs in distant species such as Caenorhabditis elegans and yeast. A few FRDA patients were found to have point mutations in X25, but the majority were homozygous for an unstable GAA trinucleotide expansion in the first X25 intron.

Environmental NMR: Fast-field-cycling Relaxometry

1996

Fast-field-cycling (FFC) NMR relaxometry deals with the variation of the spin–lattice relaxation times (T1) in a complex system, as the strength of the applied magnetic field is changed. Information about molecular dynamics can be achieved. Until now, only model theories for FFC NMR relaxometry have been developed for polymer and material sciences. Just a few applications have been performed in the environmental sciences. These mainly deal with soil porosity, rock permeability, biomass transformations, and natural organic matter dynamics. Further, FFC NMR relaxometry can also be applied to monitor the environmental fate of contaminants, to understand the dynamics of nutrients at the soil–pl…

The molecular structure of N-hydroxyurea

1996

Ab initio calculations were performed on the tautomers and conformers of N-hydroxyurea using a 6-31G** basis set. The minimum-energy structures have been found and the importance of the intramolecular hydrogen bond as the stabilizing factor was pointed out. © 1996 John Wiley & Sons, Inc.

New leptoquark mechanism of neutrinoless double beta decay

1996

A new mechanism for neutrinoless double beta ($\znbb$) decay based on leptoquark exchange is discussed. Due to the specific helicity structure of the effective four-fermion interaction this contribution is strongly enhanced compared to the well-known mass mechanism of $\znbb$ decay. As a result the corresponding leptoquark parameters are severely constrained from non-observation of $\znbb$-decay. These constraints are more stringent than those derived from other experiments.

Measurement of the Longitudinal, Transverse, and Longitudinal-Transverse Structure Functions in theH2(e,e′p)nReaction

1996

We have separated the longitudinal ({ital f}{sub 00}), transverse ({ital f}{sub 11}), and longitudinal-transverse interference ({ital f}{sub 01}) structure functions in the {sup 2}H({ital e},{ital e}{prime}{ital p}){ital n} reaction at {ital q}{searrow}{parallel}{approx_equal} 400 MeV/{ital c} and {omega}{approx_equal}110 MeV. A nonrelativistic calculation which includes effects due to final state interactions, meson exchange currents, and isobar configurations agrees with the measured {ital f}{sub 11} and {ital f}{sub 01} but overpredicts {ital f}{sub 00} by 25{percent} (2{sigma}). The data are also compared to the results of previous structure function measurements. {copyright} {ital 1996…

Formation of a Porous Zirconium Oxo Phosphate with a High Surface Area by a Surfactant-Assisted Synthesis

1996

Dimensionality Dependence of the Metal-Insulator Transition in the Anderson Model of Localization

1996

The metal-insulator transition is investigated by means of the transfer-matrix method to describe the critical behavior close to the lower critical dimension 2. We study several bifractal systems with fractal dimensions between 2 and 3. Together with 3D and 4D results, these data give a coherent description of the dimensionality dependence of the critical disorder and the critical exponent in terms of the spectral dimension of the samples. We also show that the upper critical dimension is probably infinite, certainly larger than 4.

Molecular Structure of a Gypsy Element of Drosophila Subobscura (Gypsyds) Constituting a Degenerate Form of Insect Retroviruses

1996

We have determined the nucleotide sequence of a 7.5 kb full-size gypsy element from Drosophila subobscura strain H-271. Comparative analyses were carried out on the sequence and molecular structure of gypsy elements of D.subobscura (gypsyDs), D.melanogaster (gypsyDm) and D.virilis (gypsyDv). The three elements show a structure that maintains a common mechanism of expression. ORF1 and ORF2 show typical motifs of gag and pol genes respectively in the three gypsy elements and could encode functional proteins necessary for intracellular expansion. In the three ORF1 proteins an arginine-rich region was found which could constitute a RNA binding motif. The main differences among the gypsy element…

Stereochemistry of Organic Compounds. VonE. L. Eliel undS. H. Wilen. Wiley, Chichester, 1994. 1267 S. geb. 80.00 S/Broschur 29.95 £. – ISBN 0-471-016…

1996