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681.
Recently, Jack polynomials have been proposed as natural generalizations of Zk Read–Rezayi states describing non-Abelian fractional quantum Hall systems. These polynomials are conjectured to be related to correlation functions of a class of W-conformal field theories based on the Lie algebra Ak−1. These theories can be considered as non-unitary solutions of a more general series of CFTs with Zk symmetry, the parafermionic theories. Starting from the observation that some parafermionic theories admit unitary solutions as well, we show, by computing the corresponding correlation functions, that these theories provide trial wavefunctions which satisfy the same clustering properties as the non-unitary ones. We show explicitly that, although the wavefunctions constructed by unitary CFTs cannot be expressed as a single Jack polynomial, they still show a fine structure where the mathematical properties of the Jack polynomials play a major role. 相似文献
682.
Coralie Assailly Clarisse Bridot Dr. Amélie Saumonneau Paul Lottin Dr. Benoit Roubinet Dr. Eva-Maria Krammer Francesca François Federica Vena Dr. Ludovic Landemarre Dr. Dimitri Alvarez Dorta Dr. David Deniaud Dr. Cyrille Grandjean Dr. Charles Tellier Dr. Sagrario Pascual Dr. Véronique Montembault Dr. Laurent Fontaine Dr. Franck Daligault Dr. Julie Bouckaert Dr. Sébastien G. Gouin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(9):3142-3150
Bacterial sialidases (SA) are validated drug targets expressed by common human pathogens such as Streptococcus pneumoniae, Vibrio cholerae, or Clostridium perfringens. Noncovalent inhibitors of bacterial SA capable of reaching the submicromolar level are rarely reported. In this work, multi- and polyvalent compounds are developed, based on the transition-state analogue 2-deoxy-2,3-didehydro-N-acetylneuraminic (DANA). Poly-DANA inhibits the catalytic activity of SA from S. pneumoniae (NanA) and the symbiotic microorganism B. thetaiotaomicron (BtSA) at the picomolar and low nanomolar levels (expressed in moles of molecules and of DANA, respectively). Each DANA grafted to the polymer surpasses the inhibitory potential of the monovalent analogue by more than four orders of magnitude, which represents the highest multivalent effect reported so far for an enzyme inhibition. The synergistic interaction is shown to operate exclusively in the catalytic domain, and not in the flanked carbohydrate-binding module (CBM). These results offer interesting perspectives for the multivalent inhibition of other SA families lacking a CBM, such as viral, parasitic, or human SA. 相似文献
683.
684.
R. Almairac J. L. Prefaut M. Galtier C. Benoit A. Montaner H. J. Lauter 《Molecular Crystals and Liquid Crystals》2013,570(3-4):177-191
Abstract The scattering law ζ(ω) of TTF—TCNQ at 77K has been measured between 35 and 455 meV (280-3670cm?1) by inelastic neutron scattering. The data have been corrected for background then deconvoluted by a resolution function established for the spectrometer INI-B (I.L.L.) and for a powder sample. They are finally compared to the infrared and Raman measurements available. 相似文献
685.
686.
Eva Harth Anton Bosman Didier Benoit Brett Helms Jean M.J. Frchet Craig J. Hawker 《Macromolecular Symposia》2001,174(1):85-92
The tolerance of living free radical procedures to reactive functional groups, coupled with their ability to prepare well‐defined random and block copolymers is demonstrated by the use of novel α‐hydrogen alkoxyamine derivatives instead of the traditional TEMPO‐based systems. This refinement in the nitroxide structure overcomes many limitations typically associated with TEMPO and has permitted a dramatic increase in the range of monomers, which can be polymerized under controlled conditions. The ability to prepare well‐defined multi‐arm star polymers from a variety of alkoxyamine terminated vinyl and non‐vinyl linear polymers are major benefits when compared to traditional living procedures, such as anionic polymerizations. 相似文献
687.
Albert Johner Henry Benoit Jean-Franois Joanny 《Macromolecular theory and simulations》1995,4(1):45-51
The molecular weight of a Gaussian polymer chain can be obtained from the intercept of the asymptote in a plot of the inverse structure factor 1/S(q) as a function of the square of the wave vector q2. Using an ϵ expansion and scaling arguments, we show that in a good solvent the situation is more complex and that the molecular weight determination is difficult to justify. The corrections to the asymptotic behavior of the structure factor at large wave vector involve several terms that are difficult to separate experimentally. This is qualitatively explained by the nonuniform swelling of a polymer chain in a good solvent due to the existence of the chain ends. 相似文献
688.