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We introduce a class of matrix-valued radial basis functions (RBFs) of compact support that can be customized, e.g. chosen to be divergence-free. We then derive and discuss error estimates for interpolants and derivatives based on these matrix-valued RBFs. 相似文献
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Influence of Ligand Architecture on Oxidation Reactions by High‐Valent Nonheme Manganese Oxo Complexes Using Water as a Source of Oxygen 下载免费PDF全文
Prasenjit Barman Dr. Anil Kumar Vardhaman Dr. Bodo Martin Svenja J. Wörner Dr. Chivukula V. Sastri Prof. Dr. Peter Comba 《Angewandte Chemie (International ed. in English)》2015,54(7):2095-2099
Mononuclear nonheme MnIV?O complexes with two isomers of a bispidine ligand have been synthesized and characterized by various spectroscopies and density functional theory (DFT). The MnIV?O complexes show reactivity in oxidation reactions (hydrogen‐atom abstraction and sulfoxidation). Interestingly, one of the isomers (L1) is significantly more reactive than the other (L2), while in the corresponding FeIV?O based oxidation reactions the L2‐based system was previously found to be more reactive than the L1‐based catalyst. This inversion of reactivities is discussed on the basis of DFT and molecular mechanics (MM) model calculations, which indicate that the order of reactivities are primarily due to a switch of reaction channels (σ versus π) and concomitant steric effects. 相似文献
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Carbohydrate‐Based Nanocarriers Exhibiting Specific Cell Targeting with Minimum Influence from the Protein Corona 下载免费PDF全文
Biao Kang Patricia Okwieka Susanne Schöttler Svenja Winzen Dipl.‐Chem. Jens Langhanki Dr. Kristin Mohr Prof. Dr. Till Opatz Dr. Volker Mailänder Prof. Dr. Katharina Landfester Dr. Frederik R. Wurm 《Angewandte Chemie (International ed. in English)》2015,54(25):7436-7440
Whenever nanoparticles encounter biological fluids like blood, proteins adsorb on their surface and form a so‐called protein corona. Although its importance is widely accepted, information on the influence of surface functionalization of nanocarriers on the protein corona is still sparse, especially concerning how the functionalization of PEGylated nanocarriers with targeting agents will affect protein corona formation and how the protein corona may in turn influence the targeting effect. Herein, hydroxyethyl starch nanocarriers (HES‐NCs) were prepared, PEGylated, and modified on the outer PEG layer with mannose to target dendritic cells (DCs). Their interaction with human plasma was then studied. Low overall protein adsorption with a distinct protein pattern and high specific affinity for DC binding were observed, thus indicating an efficient combination of “stealth” and targeting behavior. 相似文献
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Srividya Ganapathy Svenja Kratz Que Chen Klaas J. Hellingwerf Huub J.M. de Groot Kenneth J. Rothschild Willem J. de Grip 《Photochemistry and photobiology》2019,95(4):959-968
Archaerhodopsin‐3 (AR3) is a member of the microbial rhodopsin family of hepta‐helical transmembrane proteins, containing a covalently bound molecule of all‐trans retinal as a chromophore. It displays an absorbance band in the visible region of the solar spectrum (λmax 556 nm) and functions as a light‐driven proton pump in the archaeon Halorubrum sodomense. AR3 and its mutants are widely used in neuroscience as optogenetic neural silencers and in particular as fluorescent indicators of transmembrane potential. In this study, we investigated the effect of analogs of the native ligand all‐trans retinal A1 on the spectral properties and proton‐pumping activity of AR3 and its single mutant AR3 (F229S). While, surprisingly, the 3‐methoxyretinal A2 analog did not redshift the absorbance maximum of AR3, the analogs retinal A2 and 3‐methylamino‐16‐nor‐1,2,3,4‐didehydroretinal (MMAR) did generate active redshifted AR3 pigments. The MMAR analog pigments could even be activated by near‐infrared light. Furthermore, the MMAR pigments showed strongly enhanced fluorescence with an emission band in the near‐infrared peaking around 815 nm. We anticipate that the AR3 pigments generated in this study have widespread potential for near‐infrared exploitation as fluorescent voltage‐gated sensors in optogenetics and artificial leafs and as proton pumps in bioenergy‐based applications. 相似文献
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Paul J. Ganssle Hyun D. Shin Dr. Scott J. Seltzer Dr. Vikram S. Bajaj Dr. Micah P. Ledbetter Prof. Dmitry Budker Dr. Svenja Knappe Dr. John Kitching Prof. Alexander Pines 《Angewandte Chemie (International ed. in English)》2014,53(37):9766-9770
Nuclear magnetic resonance (NMR) relaxometry and diffusometry are important tools for the characterization of heterogeneous materials and porous media, with applications including medical imaging, food characterization and oil‐well logging. These methods can be extremely effective in applications where high‐resolution NMR is either unnecessary, impractical, or both, as is the case in the emerging field of portable chemical characterization. Here, we present a proof‐of‐concept experiment demonstrating the use of high‐sensitivity optical magnetometers as detectors for ultra‐low‐field NMR relaxation and diffusion measurements. 相似文献