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991.
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Local Tb theorems with L p type testing conditions, which are not scale invariant, have been studied widely in the case of the Lebesgue measure. In the non-homogeneous world local Tb theorems have only been proved assuming scale invariant (L ∞ or BMO) testing conditions. In this paper, for the first time, we overcome these obstacles in the non-homogeneous world, and prove a nonhomogeneous local Tb theorem with L 2 type testing conditions. This paper is in the setting of the vertical and conical square functions defined using general measures and kernels. On the technique side, we demonstrate a trick of inserting Calderón–Zygmund stopping data of a fixed function into the construction of the twisted martingale difference operators. This built-in control of averages is an alternative to Carleson embedding. 相似文献
996.
Adamou Koko Dang Conrad Bertrand Tabi Henri Paul Ekobena Fouda Timoleon Crepin Kofané 《International journal of quantum chemistry》2015,115(1):34-41
DNA nonlinear charge transport is addressed in a combined Holstein–Su–Schrieffer–Heeger (HSSH) model. In the adiabatic approximation the dynamics of the system is shown to be governed by a modified discrete nonlinear Schrödinger (MDNLS) equation, where charge‐lattice coupling parameters are obvious. Attention is paid to the effective coupling parameter, , between charge and internal molecular vibrations, which importantly influences the stability/instability features of the plane wave, solution to the MDNLS equation. Region of instability are remarkably reduced, therefore predicting that increasing could progressively quench charge transport. This is confirmed by numerical simulations on the generic HSSH model, where only the charge density is excited and drives the dynamics of the global system. Polarons, as well as longitudinal and transversal nonlinear waves, are obtained and the dependence of charge transport on DNA conformation is discussed. Accordingly, the longtime evolution of the found polarons is studied and we observe a progressive extinction of its temporal evolution as increases. © 2014 Wiley Periodicals, Inc. 相似文献
997.
Olivier Terrier Sbastien Dilly Andrs Pizzorno Dominika Chalupska Jana Humpolickova Even Boua Francis Berenbaum Stphane Quideau Bruno Lina Bruno Fve Frdric Adnet Michle Sabbah Manuel Rosa-Calatrava Vincent Marchal Julien Henri Anny Slama-Schwok 《Molecules (Basel, Switzerland)》2021,26(9)
There is an urgent need for specific antiviral treatments directed against SARS-CoV-2 to prevent the most severe forms of COVID-19. By drug repurposing, affordable therapeutics could be supplied worldwide in the present pandemic context. Targeting the nucleoprotein N of the SARS-CoV-2 coronavirus could be a strategy to impede viral replication and possibly other essential functions associated with viral N. The antiviral properties of naproxen, a non-steroidal anti-inflammatory drug (NSAID) that was previously demonstrated to be active against Influenza A virus, were evaluated against SARS-CoV-2. Intrinsic fluorescence spectroscopy, fluorescence anisotropy, and dynamic light scattering assays demonstrated naproxen binding to the nucleoprotein of SARS-Cov-2 as predicted by molecular modeling. Naproxen impeded recombinant N oligomerization and inhibited viral replication in infected cells. In VeroE6 cells and reconstituted human primary respiratory epithelium models of SARS-CoV-2 infection, naproxen specifically inhibited viral replication and protected the bronchial epithelia against SARS-CoV-2-induced damage. No inhibition of viral replication was observed with paracetamol or the COX-2 inhibitor celecoxib. Thus, among the NSAID tested, only naproxen combined antiviral and anti-inflammatory properties. Naproxen addition to the standard of care could be beneficial in a clinical setting, as tested in an ongoing clinical study. 相似文献
998.
We describe several families of Lagrangian submanifolds in complex Euclidean space which are H-minimal, i.e. critical points of the volume functional restricted to Hamiltonian variations. We make use of various constructions involving planar, spherical and hyperbolic curves, as well as Legendrian submanifolds of the odd-dimensional unit sphere. 相似文献
999.
Lyes Bidi Simone Mattei Eugen Cicala Henri Andrzejewski Philippe Le Masson Jeanne Schroeder 《Optics & Laser Technology》2011,43(3):537-545
While hybrid laser welding and coating processes involve a large number of physical phenomena, it is currently impossible to predict, for a given set of influencing factors, the shape of the molten zone and the history of temperature fields inside the parts. This remains true for complex processes, such as the hybrid laser/MIG welding process, which consists in combining a laser beam with a MIG torch. The gains obtained result essentially from the synergy of the associated processes: the stability of the process, the quality of the seam realized, and the productivity are increased. This article shows how, by means of a reduced number of experiments (8), it is possible to predict the shape of the molten zone and the temperature field inside parts, for a given window of influencing factors. This method consists in combining the method of exploratory experimental designs with a numerical modelling of the thermal phenomena that occurs during the process, by using the ‘heat equivalent source” approach [1], [2], [3], [4]. Two validations of this method have been carried out: the first for a set of parameters inside the experimental design, and the other for a set of parameters that lies outside the experimental design, but inside the domain investigated. 相似文献
1000.
A two‐dimensional numerical simulation solving unsteady incompressible Navier–Stokes equations is used to study the natural varicose instability of a plane jet in the Reynolds number range of 100–900. A transient train of vortices is observed at the beginning of the computation. It disappears yielding a steady flow. This flow is then used at the basis for forced excitation in order to study the space time development of instability. A Reynolds number dependant behaviour is observed which implies that viscosity directly affects the vortex dynamics. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献