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101.
Zhangping Xiao Deng Chen Fabian Mulder Shanshan Song Petra E. van der Wouden Dr. Robbert H. Cool Prof. Dr. Barbro N. Melgert Prof. Dr. Gerrit J. Poelarends Prof. Dr. Frank J. Dekker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(1):e202103030
Macrophage migration inhibitory factor (MIF) and its homolog MIF2 (also known as D-dopachrome tautomerase or DDT) play key roles in cell growth and immune responses. MIF and MIF2 expression is dysregulated in cancers and neurodegenerative diseases. Accurate and convenient detection of MIF and MIF2 will facilitate research on their roles in cancer and other diseases. Herein, we report the development and application of a 4-iodopyrimidine based probe 8 for the selective labeling of MIF and MIF2. Probe 8 incorporates a fluorophore that allows in situ imaging of these two proteins. This enabled visualization of the translocation of MIF2 from the cytoplasm to the nucleus upon methylnitronitrosoguanidine stimulation of HeLa cells. This observation, combined with literature on nuclease activity for MIF, enabled the identification of nuclease activity for MIF2 on human genomic DNA. 相似文献
102.
In functional magnetic resonance imaging (fMRI), the general linear model test (GLMT) is widely used for brain activation detection. However, the GLMT relies on the assumption that the noise corrupting the data is Gaussian distributed. Because the majority of fMRI studies employ magnitude image reconstructions, which are Rician distributed, this assumption is invalid and has significant consequences in case the signal-to-noise ratio (SNR) is low. In this study, we show that the GLMT should not be used at low SNR. Furthermore, we propose a generalized likelihood ratio test for magnitude MR data that has the same performance compared to the GLMT for high SNR, but performs significantly better than the GLMT for low SNR. 相似文献
103.
We report measurements of the streaming current, an electrical current generated by a pressure-driven liquid flow, in individual rectangular silica nanochannels down to 70 nm in height. The streaming current is observed to be proportional to the pressure gradient and increases with the channel height. As a function of salt concentration, it is approximately constant below approximately 10 mM, whereas it strongly decreases at higher salt. Changing the sign of the surface charge is found to reverse the streaming current. The data are best modeled using a nonlinear Poisson-Boltzmann theory that includes the salt-dependent hydration state of the silica surface. 相似文献
104.
Recrystallization of the anthelmintic drug mebendazole from propionic acid yields a 1:1 molecular complex which crystallizes in the triclinic system space group
, a = 5.928(2), b = 11.066(2), c = 14.337(6)Å, = 94.89(3), = 101.56(3), = 96.18(2)°, and Z = 2 complex units in the unit cell. An x-ray diffraction study revealed an R
2
2
(8) hydrogen bonding system in the complex, involving the unprotonated imidazole N and amide N–H function of the drug and the acid carboxylic group. Complex molecules form centrosymmetric dimers by intermolecular N–H···O hydrogen bonding involving the protonated imidazole N atom and the benzoyl O atom of the drug molecule. 相似文献
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108.
H. Dekker 《Optics Communications》1976,16(1):12-15
The most probable laser mode amplitudes are calculated on the basis of the stationary momentum space solution of the Fokker-Planck equation for a continuum mode laser oscillator, which has been derived in a previous paper. Using Fourier transform techniques the expression is transformed from momentum space to configuration space, such that an integral equation results for the most probable field configuration. The kernel is calculated explicitly and the earlier presented Ginzburg-Landau equation for the laser field is recovered together with its boundary condition. 相似文献
109.
Dr. Tehila S. Koblenz Henk L. Dekker Prof. Dr. Chris G. de Koster Prof. Dr. Piet W. N. M. van Leeuwen Prof. Dr. Joost N. H. Reek 《化学:亚洲杂志》2011,6(9):2444-2462
Self‐assembly and characterization of novel heterodimeric diphosphine capsules formed by multiple ionic interactions and composed of one tetracationic diphosphine ligand and one complementary tetraanionic calix[4]arene are described. Encapsulation of a palladium atom within a diphosphine capsule is achieved successfully by using the metal complex of the tetracationic diphosphine ligand for the assembly process. In this templated approach to metal encapsulation, the transition‐metal complex is an integrated part of the capsule with the transition metal located inside the capsule and is not involved in the assembly process. We present two approaches for capsule assembly by mixing solutions of the precharged building blocks in methanol and mixing solutions of the neutral building blocks in methanol. The scope of the diphosphine capsules and the metallodiphosphine capsules is easily extended by applying tetracationic diphosphine ligands with different backbones (ethylene, diphenyl ether, and xanthene) and cationic binding motifs (p‐C6H4‐CH2‐ammonium, m‐C6H4‐ammonium, and m‐C6H4‐guanidinium). These tetracationic building blocks with different flexibilities and shapes readily associate into capsules with the proper capsular structure, as is indicated by 1H NMR spectroscopy, 1D NOESY, ESI‐MS, and modeling studies. 相似文献
110.
A quantitative measure is proposed to evaluate and optimize the design of quantitative atomic resolution TEM experiments. It aims at precise measurement of unknown structure parameters. Specifically, the proposed measure quantifies the statistical precision with which positions of atom columns can be estimated. The optimal design is then given by the combination of microscope settings for which this precision is highest. The proposed measure is also used to find out if new instrumental developments improve the precision as compared to existing methods. 相似文献