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31.
《Electrophoresis》2017,38(3-4):507-512
LIF detection often requires labeling of analytes with fluorophores; and fast fluorescent derivatization is valuable for high‐throughput analysis with flow‐gated CE. Here, we report a fast fluorescein‐labeling scheme for amino acid neurotransmitters, which were then rapidly separated and detected in flow‐gated CE. This scheme was based on the reaction between primary amines and o‐phthalaldehyde in the presence of a fluorescent thiol, 2‐((5‐fluoresceinyl)aminocarbonyl)ethyl mercaptan (FACE‐SH). The short reaction time (<30 s) was suited for on‐line mixing and derivatization that was directly coupled with flow‐gated CE for rapid electrophoretic separation and sensitive LIF detection. To maintain the effective concentration of reactive FACE‐SH, Tris(2‐carboxyethyl)phosphine was added to the derivatization reagents to prevent thiol loss due to oxidation. This labeling scheme was applied to the detection of neurotransmitters by coupling in vitro microdialysis with online derivatization and flow‐gated CE. It is also anticipated that this fluorophore tagging scheme would be valuable for on‐chip labeling of proteins retained on support in SPE. 相似文献
32.
《Journal of computational chemistry》2017,38(6):389-394
pyMolDyn is an interactive viewer of atomic systems defined in a unit cell and is particularly useful for crystalline and amorphous materials. It identifies and visualizes cavities (vacancies, voids) in simulation cells corresponding to all seven 3D Bravais lattices, makes no assumptions about cavity shapes, allows for atoms of different size, and locates the cavity centers (the centers of the largest spheres not including an atom center). We define three types of cavity and develop a method based on the split and merge algorithm to calculate all three. The visualization of the cavities uses the marching cubes algorithm. The program allows one to calculate and export pair distribution functions (between atoms and/or cavities), as well as bonding and dihedral angles, cavity volumes and surface areas, and measures of cavity shapes, including asphericity, acylindricity, and relative shape anisotropy. The open source Python program is based on GR framework and GR3 routines and can be used to generate high resolution graphics and videos. © 2016 Wiley Periodicals, Inc. 相似文献
33.
The toughness of a (noncomplete) graph G is the minimum value of t for which there is a vertex cut A whose removal yields components. Determining toughness is an NP‐hard problem for general input graphs. The toughness conjecture of Chvátal, which states that there exists a constant t such that every graph on at least three vertices with toughness at least t is hamiltonian, is still open for general graphs. We extend some known toughness results for split graphs to the more general class of 2K2‐free graphs, that is, graphs that do not contain two vertex‐disjoint edges as an induced subgraph. We prove that the problem of determining toughness is polynomially solvable and that Chvátal's toughness conjecture is true for 2K2‐free graphs. 相似文献
34.
Viscosity Approximation Methods for Generalized Multi-Valued Nonexpansive Mappings with Applications
AbstractIn this article, we study viscosity approximation methods for generalized multi-valued nonexpansive mappings and we present some new results related to strong convergence, variational inequality, convex optimization, split and common split feasibility problems (SFPs). Some numerical computations are also presented to illustrate our results. 相似文献
35.
Charles Paquette 《代数通讯》2013,41(12):4617-4626
Let k be a field, Q a quiver with countably many vertices and I an ideal of kQ such that kQ/I is a spectroid. In this note, we prove that there is no almost split sequence ending at an indecomposable not finitely presented representation of the bound quiver (Q, I). We then get that an indecomposable representation M of (Q, I) is the ending term of an almost split sequence if and only if it is finitely presented and not projective. The dual results are also true. 相似文献
36.
Wolfgang Rump 《代数通讯》2013,41(8):2808-2824
Let R be a complete discrete valuation ring with quotient field K, and let Λ be an R-order in a semisimple K-algebra. For an indecomposable Λ-lattice E, a sublattice Bi E satisfying Rad E ? Bi E is defined, and it is shown that the middle term H of an almost split sequence τE ? H ? E can be obtained by an amalgamation of E/Bi E with E′/τE for a suitable overlattice E′ of τE. The method is bound to dim R = 1. 相似文献
37.
Vladimir I. Levenshtein 《Designs, Codes and Cryptography》1997,12(2):131-160
A system of (Boolean) functions in
variables is called randomized if the functions preserve the property of their variables to be independent and uniformly distributed random variables. Such a system is referred to as
-resilient if for any substitution of constants for any
variables, where 0 i t, the derived system of functions in
variables will be also randomized. We investigate the problem of finding the maximum number
of functions in
variables of which any
form a
-resilient system. This problem is reduced to the minimization of the size of certain combinatorial designs, which we call split orthogonal arrays. We extend some results of design and coding theory, in particular, a duality in bounding the optimal sizes of codes and designs, in order to obtain upper and lower bounds on
. In some cases, these bounds turn out to be very tight. In particular, for some infinite subsequences of integers
they allow us to prove that
,
,
,
,
. We also find a connection of the problem considered with the construction of unequal-error-protection codes and superimposed codes for multiple access in the Hamming channel. 相似文献
38.
Dongfang Li Hongyu Qin Xiujun Cheng Fengyan Wu 《Mathematical Methods in the Applied Sciences》2016,39(8):1935-1944
In this study, a parameterized split Newton method is derived by using the accelerating technique. Convergence and error estimates of the method are obtained. In practical application, the proposed method can give a better result in view of computational CPU time. Numerical examples on several partial differential equations are shown to illustrate our findings. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
39.
Some subgradient extragradient type algorithms for solving split feasibility and fixed point problems 下载免费PDF全文
In this paper, we consider the split feasibility problem (SFP) in infinite‐dimensional Hilbert spaces and propose some subgradient extragradient‐type algorithms for finding a common element of the fixed‐point set of a strict pseudocontraction mapping and the solution set of a split feasibility problem by adopting Armijo‐like stepsize rule. We derive convergence results under mild assumptions. Our results improve some known results from the literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
40.
The purpose of this paper is to introduce a split generalized mixed equilibrium problem (SGMEP) and consider some iterative sequences to find a solution of the generalized mixed equilibrium problem such that its image under a given bounded linear operator is a solution of another generalized mixed equilibrium problem. We obtain some weak and strong convergence theorems. 相似文献