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51.
Liang Chen Yu Fan Jieru Qiu Dr. Régis Laurent Jin Li Prof. Dr. Jérôme Bignon Prof. Dr. Serge Mignani Prof. Dr. Anne-Marie Caminade Prof. Dr. Xiangyang Shi Prof. Dr. Jean-Pierre Majoral 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5903-5910
First-in-class CuII and AuIII metaled phosphorus dendrons were synthesized and showed significant antiproliferative activity against several aggressive breast cancer cell lines. The data suggest that the cytotoxicity increases with reducing length of the alkyl chains, whereas the replacement of CuII with AuIII considerably increases the antiproliferative activity of metaled phosphorus dendrons. Very interestingly, we found that the cell death pathway is related to the nature of the metal complexed by the plain dendrons. CuII metaled dendrons showed a potent caspase-independent cell death pathway, whereas AuIII metaled dendrons displayed a caspase-dependent apoptotic pathway. The complexation of plain dendrons with AuIII increased the cellular lethality versus dendrons with CuII and promoted the translocation of Bax into the mitochondria and the release of Cytochrome C (Cyto C). 相似文献
52.
We report the experimental observation of new resonances in saturated absorption spectra of a J = 1 to J = 0 transition of Ne atoms in a static magnetic field. These resonances, which are distinct from the well-known Zeeman and cross-over resonances, result from the modification of stimulated Raman processes by the simultaneous resonant saturation of an optical transition. The light-shifts of the various resonances are also studied. 相似文献
53.
Benoit Roberge Serge Jandl Agung A. Nugroho Thomas T. M. Palstra Le D. Tung Geetha Balakrishnan 《Journal of Raman spectroscopy : JRS》2015,46(11):1157-1160
The coexistence at low temperature in YVO3 and LaVO3 of two competing phases with defined orbital and spin orientations is studied by Raman spectroscopy. The temperature evolution of the phonons indicates that phase coexistence, due to strain in YVO3 and fluctuations in LaVO3, is not restricted to small R ionic radius in RVO3 compounds. Also, a typical temperature at 50 K is inferred from the temperature dependence of the intensities in LaVO3. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
54.
We study sequences of empirical measures of Euler schemes associated to some non-Markovian SDEs: SDEs driven by Gaussian processes with stationary increments. We obtain the functional convergence of this sequence to a stationary solution to the SDE. Then, we end the paper by some specific properties of this stationary solution. We show that, in contrast to Markovian SDEs, its initial random value and the driving Gaussian process are always dependent. However, under an integral representation assumption, we also obtain that the past of the solution is independent of the future of the underlying innovation process of the Gaussian driving process. 相似文献
55.
This paper deals with a control-constrained linear-quadratic optimal control problem governed by the Stokes equations. It
is concerned with situations where the gradient of the velocity field is not bounded. The control is discretized by piecewise
constant functions. The state and the adjoint state are discretized by finite element schemes that are not necessarily conforming.
The approximate control is constructed as projection of the discrete adjoint velocity in the set of admissible controls. It
is proved that under certain assumptions on the discretization of state and adjoint state this approximation is of order 2
in L
2(Ω). As first example a prismatic domain with a reentrant edge is considered where the impact of the edge singularity is counteracted
by anisotropic mesh grading and where the state and the adjoint state are approximated in the lower order Crouzeix-Raviart
finite element space. The second example concerns a nonconvex, plane domain, where the corner singularity is treated by isotropic
mesh grading and state and adjoint state can be approximated by a couple of standard element pairs. 相似文献
56.
Serge Haroche 《Hyperfine Interactions》1998,114(1-4):87-101
A Rydberg atom coupled to a single field mode in a high Q superconducting cavity is an ideal tool to perform experiments testing the most puzzling aspects of the quantum theory. The coupling between the atom and the field is either resonant or dispersive. In the resonant case, quantum Rabi oscillations in the vacuum or in a small coherent field injected in the cavity are observed. The analysis of these signals reveals in a striking way the quantization of the field. Quantum Rabi oscillations are also used to produce entanglement between successive atoms crossing the cavity. Dispersive atom-field coupling is used to prepare coherent superpositions of field states with different phases (Schrödinger cat states). The progressive decoherence of these states is studied by measuring correlations between the energies of pairs of atoms sent through the cavity with a variable delay between them. These experiments provide fundamental tests of quantum theory and shed light on the transition from quantum to classical in mesoscopic systems. 相似文献
57.
Termination criteria for the iterative solution of bound-constrained optimization problems are examined in the light of backward
error analysis. It is shown that the problem of determining a suitable perturbation on the problem’s data corresponding to
the definition of the backward error is analytically solvable under mild assumptions. Moreover, a link between existing termination
criteria and this solution is clarified, indicating that some standard measures of criticality may be interpreted in the sense
of backward error analysis. The backward error problem is finally considered from the multicriteria optimization point of
view and some numerical illustration is provided. 相似文献
58.
Xiaoyu Liu Serge Guillas Ming-Jun Lai 《Journal of computational and graphical statistics》2016,25(4):1176-1194
Gaussian fields (GFs) are frequently used in spatial statistics for their versatility. The associated computational cost can be a bottleneck, especially in realistic applications. It has been shown that computational efficiency can be gained by doing the computations using Gaussian Markov random fields (GMRFs) as the GFs can be seen as weak solutions to corresponding stochastic partial differential equations (SPDEs) using piecewise linear finite elements. We introduce a new class of representations of GFs with bivariate splines instead of finite elements. This allows an easier implementation of piecewise polynomial representations of various degrees. It leads to GMRFs that can be inferred efficiently and can be easily extended to nonstationary fields. The solutions approximated with higher order bivariate splines converge faster, hence the computational cost can be alleviated. Numerical simulations using both real and simulated data also demonstrate that our framework increases the flexibility and efficiency. Supplementary materials are available online. 相似文献
59.
Galtchouk Leonid I. Pergamenshchikov Serge M. 《Statistical Inference for Stochastic Processes》2022,25(1):127-158
Statistical Inference for Stochastic Processes - We consider drift estimation problems for high dimension ergodic diffusion processes in nonparametric setting based on observations at discrete... 相似文献
60.
Summary. We consider the heat equation in a smooth domain of R
with Dirichlet and Neumann boundary conditions. It is solved by using its integral formulation with double-layer potentials,
where the unknown , the jump of the solution through the boundary, belongs to an anisotropic Sobolev space. We approximate by the Galerkin method and use a prewavelet basis on , which characterizes the anisotropic space. The use of prewavelets allows to compress the stiffness matrix from to when N is the size of the matrix, and the condition number of the compressed matrix is uniformly bounded as the initial one in the
prewavelet basis. Finally we show that the compressed scheme converges as fast as the Galerkin one, even for the Dirichlet
problem which does not admit a coercive variational formulation.
Received April 16, 1999 / Published online August 2, 2000 相似文献