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1.
Unexpected benzimidazole ring formation from a quinoneimide species in the presence of ammonium acetate as supporting electrolyte used in the coupling of electrochemistry with mass spectrometry
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2.
Denis Kudryavtsev Anastasia Isaeva Daria Barkova Ekaterina Spirova Renata Mukhutdinova Igor Kasheverov Victor Tsetlin 《Molecules (Basel, Switzerland)》2021,26(5)
Slow-channel congenital myasthenic syndromes (SCCMSs) are rare genetic diseases caused by mutations in muscle nicotinic acetylcholine receptor (nAChR) subunits. Most of the known SCCMS-associated mutations localize at the transmembrane region near the ion pore. Only two SCCMS point mutations are at the extracellular domains near the acetylcholine binding site, α1(G153S) being one of them. In this work, a combination of molecular dynamics, targeted mutagenesis, fluorescent Ca2+ imaging and patch-clamp electrophysiology has been applied to G153S mutant muscle nAChR to investigate the role of hydrogen bonds formed by Ser 153 with C-loop residues near the acetylcholine-binding site. Introduction of L199T mutation to the C-loop in the vicinity of Ser 153 changed hydrogen bonds distribution, decreased acetylcholine potency (EC50 2607 vs. 146 nM) of the double mutant and decay kinetics of acetylcholine-evoked cytoplasmic Ca2+ rise (τ 14.2 ± 0.3 vs. 34.0 ± 0.4 s). These results shed light on molecular mechanisms of nAChR activation-desensitization and on the involvement of such mechanisms in channelopathy genesis. 相似文献
3.
Synthesis,Electronic Properties and WOLED Devices of Planar Phosphorus‐Containing Polycyclic Aromatic Hydrocarbons
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Dr. François Riobé Rózsa Szűcs Dr. Pierre‐Antoine Bouit Dr. Denis Tondelier Bernard Geffroy Fátima Aparicio Julia Buendía Prof. Luis Sánchez Prof. Régis Réau Prof. László Nyulászi Prof. Muriel Hissler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6547-6556
We describe the synthesis and the physical properties of polyaromatic hydrocarbons (PAHs) containing a phosphorus atom at the edge. In particular, the impact of the successive addition of aromatic rings on the electronic properties was investigated by experimental (UV/Vis absorption, fluorescence, cyclic voltammetry) and theoretical studies (DFT). The physical properties recorded in solution and in the solid state showed that the P‐containing PAHs exhibit properties expected for an emitter in white organic light‐emitting diodes (WOLEDs). 相似文献
4.
T.S. Khlebnicova V.G. Isakova A.V. Baranovsky E.V. Borisov F.A. Lakhvich 《Journal of fluorine chemistry》2006,127(12):1564-1569
A one-pot synthesis of 2-perfluoroalkanoylcyclohexane-1,3-diones via C-acylation of cyclohexane-1,3-diones with N-perfluoroacylimidazole as an acylating agent is reported. A reaction was examined with isolated N-trifluoroacetylimidazole and with N-perfluoroacylimidazoles generated in situ from perfluorocarboxylic acid anhydrides or perfluorocarboxylic acids. 相似文献
5.
In this paper, we obtain a nonlinear Poisson structure and two first integrals in the problem of the plane motion of a circular cylinder and n point vortices in an ideal fluid. This problem is a priori not Hamiltonian; specifically, in the case n= 1 (i.e., in the problem of the interaction of a cylinder with a vortex) it is integrable. 相似文献
6.
We obtain exponential upper bounds for tails of distributions of generalized L-statistics based on a sample from an exponential distribution. We prove the asymptotic normality of generalized L-statistics based on a sample from the uniform distribution on [0,1] and of L-statistics with decomposed kernels (without any restrictions on the sample distribution type). 相似文献
7.
Ab initio calculations showed that the tetrachlorodibenzo-para-dioxin radical cations (TCDD RCs) with a planar structure have two steady states with asymmetric dioxin cycles. The activation barriers between these states are up to 2 kcal/mole, so that the RCs may be regarded as being structurally nonrigid within the dioxin cycle. The 2,3,7,8-TCDD RC is more stable than the 1,4,6,9-TCDD RC, the energy difference being 5.2 kcal/mole. The adiabatic ionization potential of 2,3,7,8-TCDD (7.54 eV) is 0.1 eV smaller than the corresponding potential of 1,4,6,9-TCDD. These factors account for the increased hemoproteide affinity and hence increased biological activity of 2,3,7,8-TCDD. 相似文献
8.
Consider the problem of rolling a dynamically asymmetric balanced ball (the Chaplygin ball) over a sphere. Suppose that the
contact point has zero velocity and the projection of the angular velocity to the normal vector of the sphere equals zero.
This model of rolling differs from the classical one. It can be realized, in some approximation, if the ball is rubber coated
and the sphere is absolutely rough. Recently, J. Koiller and K. Ehlers pointed out the measure and the Hamiltonian structure
for this problem. Using this structure we construct an isomorphism between this problem and the problem of the motion of a
point on a sphere in some potential field. The integrable cases are found.
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9.
Siegfried Grossmann Denis Jérome Antonio Paoletti 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):447
We mourn the death of Professor Dr. Gilbert Grynberg, April 17, 1948 - January 27, 2003. We have lost an excellent and highly esteemed scientist, an outstanding character and a good friend. He has been a very active colleague in the merger of Zeitschrift für Physik and Journal de Physique in the early days. As one of the Co-Editors-in-Chief of The European Physical Journal D, from its start, he has formed the scienti.c standards of EPJ. Untiringly he has served our Journal with greatest dedication. We are grateful that he has been with us. The editorial board and o.ce of EPJ B Siegfried Grossmann, Denis Jérome, Antonio Paoletti 相似文献
10.
A theoretical study of the electron dynamics in image potential states on Cu(1 0 0) surfaces with different types of adsorbates is presented. Scattering of the image state electron by an adsorbate induces inter-band and intra-band transitions leading respectively to the population decay and to the dephasing of the image state. We compare results obtained with low coverage (typically 1 adsorbate atom per 1000 surface atoms) Cs, Ar, and a model electronegative adsorbates. As follows from our results, Cs adsorbates lead to both appreciable dephasing and decay, while electronegative adsorbates mostly affect the dephasing rate. The effect of low coverage Ar adsorbates is small, consistent with their neutrality. 相似文献