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81.
Dr. Jérémie Topin Claire A. de March Dr. Landry Charlier Prof. Dr. Catherine Ronin Prof. Dr. Serge Antonczak Dr. Jérôme Golebiowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10227-10230
A joint approach combining free‐energy calculations and calcium‐imaging assays on the broadly tuned human 1G1 olfactory receptor is reported. The free energy of binding of ten odorants was computed by means of molecular‐dynamics simulations. This state function allows separating the experimentally determined eight agonists from the two non‐agonists. This study constitutes a proof‐of‐principle for the computational deorphanization of olfactory receptors. 相似文献
82.
Markus Suta Flavie Lavoie‐Cardinal Claudia Wickleder 《Angewandte Chemie (International ed. in English)》2020,59(27):10949-10954
Inorganic hosts, such as SrB4O7 or certain nitrides, intrinsically stabilize Eu2+ even when the dopant is an Eu3+‐based precursor and reducing conditions are not employed in the synthesis. Although this concept is well known in the synthesis of phosphorescent materials, the mechanistic details are scarcely understood. Herein, we demonstrate that trapped charge carriers, such as color centers, can also act as redox partners to stabilize certain oxidation states of activators. Eu‐activated CsMgCl3 and CsMgBr3 are used as examples. Upon doping with EuCl3 and in the absence of reducing conditions during the synthesis, dominant cyan or green luminescence from Eu2+ ions was observed. Photoluminescence spectroscopy at 10 K revealed that the reduction is correlated to color centers localized at defects. Although defects are typically undesired in phosphors, we have shown that their role may be underestimated and they could be used on purpose in the preparation of selected inorganic phosphors. 相似文献
83.
QIU Ping NI Yong-nian KOKOT Serge 《高等学校化学研究》2007,23(1):14-17
IntroductionOrganophosphorus pesticides( OPPs) are widelyused in agriculture as insecticides, but they are foundto contaminate agricultural products such as fruits andvegetables to variable extents. Because of their toxicproperties[1,2]and the potential r… 相似文献
84.
85.
The rheological properties of two model suspensions using a Newtonian polymeric matrix are presented and discussed in light of results presented in the literature. It is shown that particle-particle interactions in concentrated suspensions are responsible for a gel-type behavior at very small strain and strain hardening at a critical strain. Suspensions of concentrated colloidal particles in a Newtonian matrix behave like typical viscoelastic molten polymers, but the properties are strongly dependent on the solids dispersion, and strain at small strain. A simple rheological model is proposed to describe the shear viscosity of these suspensions. 相似文献
86.
87.
Philip N Klein Serge A Plotkin Satish Rao Éva Tardos 《Journal of Algorithms in Cognition, Informatics and Logic》1997,22(2):241-269
In this paper we consider theSteiner multicutproblem. This is a generalization of the minimum multicut problem where instead of separating nodepairs, the goal is to find a minimum weight set of edges that separates all givensetsof nodes. A set is considered separated if it is not contained in a single connected component. We show anO(log3(kt)) approximation algorithm for the Steiner multicut problem, wherekis the number of sets andtis the maximum cardinality of a set. This improves theO(t log k) bound that easily follows from the previously known multicut results. We also consider an extension of multicuts to directed case, namely the problem of finding a minimum-weight set of edges whose removal ensures that none of the strongly connected components includes one of the prespecifiedknode pairs. In this paper we describe anO(log2 k) approximation algorithm for this directed multicut problem. Ifk ? n, this represents an improvement over theO(log n log log n) approximation algorithm that is implied by the technique of Seymour. 相似文献
88.
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
89.
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
90.
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