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121.
Li Y Shi L Qin LX Qu LL Jing C Lan M James TD Long YT 《Chemical communications (Cambridge, England)》2011,47(15):4361-4363
A green fluorescent protein chromophore inspired chemosenor for Zn(2+) was designed and synthesized. A Zn(2+) specific fluorescence enhancement was observed due to restricted rotation between the 1,10-phenanthroline and imidazolone moieties. 相似文献
122.
Wei Hu Taotao Qiang Chenchen Li Longfang Ren Fei Cheng Baoshuai Wang Mingli Li Xinjian Song Tony D. James 《Chemical science》2022,13(37):11140
Small-molecule near-infrared (NIR) imaging facilitates deep tissue penetration, low autofluorescence, non-invasive visualization, and a relatively simple operation. As such it has emerged as a popular technique for tracking biological species and events. However, the small Stokes shift of most NIR dyes often results in a low signal-to-noise ratio and self-quenching due to crosstalk between the excitation and emission spectra. With this research, we developed a NIR-based fluorescent probe WD-HOCl for hypochlorous acid (HOCl) detection using the NIR dye TJ730 as the fluorophore, which exhibits a large Stokes shift of 156 nm, with no crosstalk between the excitation and emission spectra. It contains acyl hydrazide as the responsive group and a pyridinium cation as the mitochondria-targeting group. The fluorescence intensity of WD-HOCl was enhanced by 30.1-fold after reacting with HOCl. Imaging studies performed using BV-2 cells indicated that WD-HOCl could be used for endogenous HOCl detection and imaging in living cells exposed to glucose and oxygen deprivation/reperfusion. Finally, we demonstrated that inhibiting the expression of NOX2 reduced the HOCl levels and the severity of oxidative stress during stroke in a mouse model.Small-molecule near-infrared (NIR) imaging facilitates deep tissue penetration, low autofluorescence, non-invasive visualization, and a relatively simple operation. 相似文献
123.
Mathematical Programming - A clutter is k-wise intersecting if every k members have a common element, yet no element belongs to all members. We conjecture that, for some integer $$k\ge 4$$ , every... 相似文献
124.
Readily available arabinose-derived 4-uloses, containing a tunable butane-2,3-diacetal as the steric sensor, displayed increasing enantioselectivity (up to 93% ee) with the size of the acetal alkyl group in catalytic asymmetric epoxidation of trans-disubstituted and trisubstituted alkenes. 相似文献
125.
Tony E. Smith 《Applied mathematics and computation》1984,14(1):35-62
A set of necessary and sufficient conditions is established for the representability of choice probabilities by additive random utility models with generalized extreme value (GEV) distributions of utilities. These conditions yield an operational testing procedure for GEV-representability which does not require explicit construction of the underlying distribution of utilities. In addition, this characterization of GEV models reveals a number of their underlying behavioral features. 相似文献
126.
We present a transpose-free version of the nonsymmetric scaled Lanczos procedure. It generates the same tridiagonal matrix
as the classical algorithm, using two matrix–vector products per iteration without accessing AT. We apply this algorithm to obtain a transpose-free version of the Quasi-minimal residual method of Freund and Nachtigal
[15] (without look-ahead), which requires three matrix–vector products per iteration. We also present a related transpose-free
version of the bi-conjugate gradients algorithm.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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129.
Journal of the Operational Research Society - 相似文献
130.