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1.
Prof. Dr. Francisco Melo Leonardo Caballero Esteban Zamorano Natalia Ventura Camilo Navarro Irving Doll Prof. Dr. Pedro Zamorano Prof. Dr. Alberto Cornejo 《Chemphyschem》2021,22(6):526-532
Parkinson's disease is a neurodegenerative disorder involving a functional protein, α-synuclein, whose primary function is related to vesicle trafficking. However, α-synuclein is prone to form aggregates, and these inclusions, known as Lewy bodies, are the hallmark of Parkinson's disease. α-synuclein can alter its conformation and acquire aggregating capacity, forming aggregates containing β-sheets. This protein's pathogenic importance is based on its ability to form oligomers that impair synaptic transmission and neuronal function by increasing membrane permeability and altering homeostasis, generating a deleterious effect over cells. First, we establish that oligomers interfere with the mechanical properties of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) membrane, as demonstrated by nanoindentation curves. In contrast, nanoindentation revealed that the α-synuclein monomer's presence leads to a much more resistant lipid bilayer. Moreover, the oligomers’ interaction with cell membranes can promote lactate dehydrogenase (LDH) release, suggesting the activation of cytotoxic events. 相似文献
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In this Note we give a necessary and sufficient condition for the spectral controllability from one simple node of a general network of strings that undergoes transversal vibrations in a sufficiently large time. This condition asserts that no eigenfunction vanishes identically on the string that contains the controlled node. The proof combines the Beurling–Malliavin's theorem and an asymptotic formula for the eigenvalues of the network. The optimal control time may be characterized as twice the sum of the lengths of all the strings of the network. To cite this article: R. Dáger, E. Zuazua, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 545–550. 相似文献
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When an organization solves a portfolio problem with public projects evaluated by multiple criteria, in which the economic dimension is not essential or not well characterized, the classical methods are not useful. We propose a non-linear preference model developed from normative Value Theory and using fuzzy sets to model some sources of imprecision. This model can be considered as a generalization of the classical approaches. However, the optimization problem is very complex in order to be solved with non-linear programming techniques. Therefore, the model is exploited by an evolutionary algorithm, able to achieve a strong improvement of the quality of solution. 相似文献
6.
Enrique Fernández-Cara Sergio Guerrero Oleg Yurievich Imanuvilov Jean-Pierre Puel 《Comptes Rendus Mathematique》2004,338(5):375-380
This Note deals with the controllability of Stokes and Navier–Stokes systems with distributed controls with support in possibly small subdomains. We first present a new global Carleman inequality for the solutions to Stokes-like systems that leads to the null controllability at any time T>0. Then, we present a local result concerning exact controllability to trajectories of the Navier–Stokes system. To cite this article: E. Fernández-Cara et al., C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
7.
Antonio Guirado Enrique LópezSánchez Raquel Andreu Andrés Zapata 《Tetrahedron letters》2004,45(10):2075-2076
The first method for the synthesis of the title compounds has been established involving a stereoselective electrochemical diacylation process. The cathodic reductions of monothiobenzils in an aprotic medium, under constant potential, in the presence of twofold molecular amounts of aroyl chlorides provide previously unknown (Z)-α-benzoyloxy-β-benzoythiostilbenes in high to quantitative yields. 相似文献
8.
On a Definitizable Analog of the Trigonometric Moment Problem Generating an Indefinite Toeplitz Form
We prove the existence of an integro-polynomial representation for a sequence of numbers such that there exists a difference operator mapping this sequence to a sequence that generates the solvable trigonometric moment problem. A similar result related to the power moment problem was given in [12]. 相似文献
9.
G. Garcia-Belmonte J. Bisquert L. M. Navarro J. R. Jurado F. M. B. Marques 《Ionics》1995,1(5-6):377-383
In ionic conductors, long range-migrating charges are a main cause of polarization processes. This has complicated, up to
date, the study of ionic thermocurrents (ITC) in solid electrolytes. However, the method is appealing, as it probes directly
charge-formation phenomena that are important both from a scientific point of view and for applications.
This work reports on the observation of ITC in solid electrolytes. Under appropriate experimental conditions, the ITC response
of a zirconia sample electroded with platinum is a reproducible one, thus opening the way to a new characterization method
that may complement other well established methods, such as Impedance Spectroscopy and a number of electrochemical techniques.
The general trends of the response, which is composed of two well resolved ITC peaks, is discussed. One of them, taking place
at higher temperatures, conforms to the standard shape of a first order kinetics depolarization process.
Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, Sept. 10–16, 1995 相似文献
10.