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排序方式: 共有1051条查询结果,搜索用时 31 毫秒
1.
Dr. Chenge Li Dr. Alison G. Tebo Marion Thauvin Marie-Aude Plamont Prof. Dr. Michel Volovitch Dr. Xavier Morin Prof. Dr. Sophie Vriz Prof. Dr. Arnaud Gautier 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(41):18073-18079
Far-red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we describe the generation of frFAST (far-red Fluorescence Activating and absorption Shifting Tag), a 14-kDa monomeric protein that forms a bright far-red fluorescent assembly with (4-hydroxy-3-methoxy-phenyl)allylidene rhodanine (HPAR-3OM). As HPAR-3OM is essentially non-fluorescent in solution and in cells, frFAST can be imaged with high contrast in presence of free HPAR-3OM, which allowed the rapid and efficient imaging of frFAST fusions in live cells, zebrafish embryo/larvae, and chicken embryos. Beyond enabling the genetic encoding of far-red fluorescence, frFAST allowed the design of a far-red chemogenetic reporter of protein–protein interactions, demonstrating its great potential for the design of innovative far-red emitting biosensors. 相似文献
2.
3.
François Bolley Arnaud Guillin Cédric Villani 《Probability Theory and Related Fields》2007,137(3-4):541-593
We establish quantitative concentration estimates for the empirical measure of many independent variables, in transportation
distances. As an application, we provide some error bounds for particle simulations in a model mean field problem. The tools
include coupling arguments, as well as regularity and moment estimates for solutions of certain diffusive partial differential
equations. 相似文献
4.
In this paper we introduce and study a weakened form of logarithmic Sobolev inequalities in connection with various others
functional inequalities (weak Poincaré inequalities, general Beckner inequalities, etc.). We also discuss the quantitative
behaviour of relative entropy along a symmetric diffusion semi-group. In particular, we exhibit an example where Poincaré
inequality can not be used for deriving entropic convergence whence weak logarithmic Sobolev inequality ensures the result.
相似文献
5.
6.
Yu Yang Maya Belghazi Arnaud Lagadec David J. Miller Steven B. Hawthorne 《Journal of chromatography. A》1998,810(1-2):149-159
The intermolecular interactions between organic solutes and sorbent matrices under subcritical water conditions have been investigated at a pressure of 50 bar and temperatures ranging from 50 to 250°C. Both polar and nonpolar organics (chlorophenols, amines, n-alkanes, and polycyclic aromatic hydrocarbons) and five different sorbent matrices (glass beads, alumina, Florisil, silica-bonded C18, and polymeric XAD-4 resins) were used. From the same matrix, the polar solutes always eluted at lower temperatures, while the moderately polar and nonpolar solutes only eluted at higher temperatures. Similar to matrix effects previously observed using supercritical carbon dioxide, the sorbent type greatly influenced the elution efficiency under subcritical water conditions. Lower temperatures are sufficient to elute a particular solute from glass beads, alumina, and Florisil, but higher temperatures (less polar water) are needed to elute the same solute from silica-bonded C18. The highest temperatures were required to elute aromatic organics from XAD-4. These matrix effects demonstrate that, while low temperature water can break inert or dipole interactions between solutes and glass beads, alumina, and Florisil, higher temperature water is required to interrupt the van der Waals attractions between solutes and silica-bonded C18, and even higher temperatures needed to overcome the π-electron interactions between aromatic solutes and XAD-4. 相似文献
7.
The rates of self-exchange electron transfer in the trimethylphosphine complex of cytochrome c have been measured by an NMR technique over a large range of ionic strengths. The rate constant is 1.56 x 10(4) M(-)(1) s(-)(1) at 23 degrees C (&mgr; = 0.34 M) at pH 6.9. Dependence on ionic strength of the rate constant is treated by van Leeuwen theory. Extrapolation of the rate constant to infinite ionic strength gives a rate constant of 3.9 x 10(5) M(-)(1) s(-)(1). This rate constant is compared with others reported for myoglobin and cytochrome b(5)(). The values for these systems range over 2 orders of magnitude with myoglobin-PMe(3) < cytochrome b(5)() < cytochrome c-PMe(3) < cytochrome c. Analysis of the data in terms of Marcus theory gives a reorganization energy, lambda, for self-exchange of 0.75 eV mol(-)(1) for cytochrome c-PMe(3). Substitution of Met-80 by PMe(3) appears to influence only weakly the rearrangement barrier to electron transfer. 相似文献
8.
Jo?o L M Santos Arnaud Clausse José L F C Lima M L M F S Saraiva António O S Rangel 《Analytical sciences》2005,21(4):461-464
A new flow methodology exploiting the multi-pumping approach was developed for the spectrophotometric determination of ambroxol hydrochloride in pharmaceutical preparations. The flow manifold was implemented by using, exclusively, multiple solenoid-actuated micro-pumps, which acted simultaneously as sample insertion, solutions propelling and reagents commutation units. Linear calibration plots were obtained over an ambroxol concentration ranging from 10 to 200 mg l(-1) (r.s.d. < 0.5%, n = 15) and a sampling rate of about 60 samples per hour (flow rate = 1.92 ml min(-1), sample volume = 80 microl). 相似文献
9.
The solvolysis in acid solution of allylic halides and acetates of methylenecyclopropanes and cyclopropylmethanes does not lead to ring opening when there is an ethoxycarbonyl substituent on the ring methylene. Only the cyclopropenyl derivative is obtained. A study of the electronic structure and the geometry of the possible allylic cation intermediate has been carried out using the MNDO method. In addition, the influence of the substituents on the ring opening of this cation has beeen examined. It appears that the ring opening is disfavoured upon substitution of an alkyl group by alkoxymethyl on the ring methylene group. 相似文献
10.
Zouhair Asfari Rym Abidi Françoise Arnaud Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(2):163-169
The template synthesis of copper(II) phthalocyanine by the condensation of dicyanobenzene within the supercages of Cu(II) exchanged X and Y type zeolites was studied using differential scanning calorimetry. The exotherms for intrazeolite and surface complexation have been resolved. These thermal events exhibit a dependence on the copper loading and hydration level which has been interpreted as a pressure effect. 相似文献