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991.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(39):12848-12851
Covalent surface immobilization of proteins for binding assays is typically performed non‐specifically via lysine residues. However, receptors that either have lysines near their binding pockets, or whose presence at the sensor surface is electrostatically disfavoured, can be hard to probe. To overcome these limitations and to improve the homogeneity of surface functionalization, we adapted and optimized three different enzymatic coupling strategies (4′‐phosphopantetheinyl transferase, sortase A, and asparaginyl endopeptidase) for biolayer interferometry surface modification. All of these enzymes can be used to site‐specifically and covalently ligate proteins of interest via short recognition sequences. The enzymes function under mild conditions and thus immobilization does not affect the receptors’ functionality. We successfully employed this enzymatic surface functionalization approach to study the binding kinetics of two different receptor–ligand pairs. 相似文献
992.
This research is devoted to the modeling of high-speed rectilinear penetration of a rigid axisymmetric body (impactor with a flat bluntness) into an elastic–plastic media with account for its rotation about the axis of symmetry. The body has an arbitrary shape of the meridian. The resistance to the motion is represented as the sum of the body drag and the contribution of friction. The dynamic system governing the body motion is derived and the qualitative and numerical analysis of the projectile movement and perforation of a slab are performed. The problem of shape optimization of impactor with a flat bluntness is studied using evolutionary algorithm. 相似文献
993.
994.
Jiu Ding 《Linear and Multilinear Algebra》2013,61(2):119-127
A classical perturbation result for nonsingular systems of linear algebraic equations is extended to general consistent systems under any norm. An optimal perturbation result is also obtained for general linear least squares problems under a Euclidean norm. 相似文献
995.
Xingzhi Zhan 《Linear and Multilinear Algebra》2013,61(2):191-194
We pose some problems on the Hadamard product and singular values of matrices. 相似文献
996.
《偏微分方程通讯》2013,38(7-8):1117-1132
Barrier type boundary conditions are modeled for describing the substance diffusion in a medium when obstacles in the medium are considered. The existence of solutions of parabolic and elliptic differential equations with barrier boundary condition is presented in this paper. 相似文献
997.
Utilisation of γ-allyl ester protection of glutamates provides a convenient route to the synthesis of Z-Glu-OBut, Tr-Glu-OBut and (Boc)2-Glu-OBut. 相似文献
998.
《合成通讯》2013,43(7):1095-1101
Abstract The intermolecular reductive coupling of 1,1-diaryl-2,2-dicyanoethylenes or 1,1-diaryl-2-cyano-2-ethoxycarbonylethylenes with substituted benzalazines induced by samarium diiodide was studied. Functionalized 2,3-dihydropyrroles were prepared in good yields under neutral and mild conditions. 相似文献
999.
We use lookback time versus redshift data from galaxy clusters (Capozziello et al., 2004 [9]) and passively evolving galaxies (Simon et al., 2005 [62]), and apply a Bayesian prior on the total age of the Universe based on WMAP measurements, to constrain dark energy cosmological model parameters. Current lookback time data provide interesting and moderately restrictive constraints on cosmological parameters. When used jointly with current baryon acoustic peak and Type Ia supernovae apparent magnitude versus redshift data, lookback time data tighten the constraints on parameters and favor slightly smaller values of the nonrelativistic matter energy density. 相似文献
1000.
Bruno Deschamps 《Journal of Number Theory》2010,130(12):2658-2670
In this article we give an infinite number of good initial values for the Lucas–Lehmer sequence. 相似文献