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排序方式: 共有221条查询结果,搜索用时 15 毫秒
81.
Andrew E. Howery Shelley Elvington Sherwin J. Abraham Kee-Hyun Choi Sierra Dworschak-Simpson Sabrina Phillips Christopher M. Ryan R. Lea Sanford Jonas Almqvist Kevin Tran Thomas A. Chew Ulrich Zachariae Olaf S. Andersen Julian Whitelegge Kimberly Matulef Justin Du Bois Merritt C. Maduke 《Chemistry & biology》2012,19(11):1460-1470
Highlights? OADS is a known small-molecule inhibitor of a CLC antiporter ? OADS specifically inhibits the ClC-ec1 antiporter but not the ClC-1 channel ? Photoaffinity labeling and mass spectrometry have localized OADS binding to two discrete sites ? The unique binding mode and lipid dependence of OADS suggest potential mechanisms of action 相似文献
82.
Wee Chew 《Journal of Raman spectroscopy : JRS》2011,42(1):36-47
A methodology of multivariate chemometric techniques based on the information‐theoretic approach was applied for elucidating chemical reaction information from a Raman data array R m×ν that arises from in situ reaction monitoring. This reaction‐induced dynamic dataset R m×ν can be contaminated by random cosmic ray spikes found in the midst of characteristic spectral variations associated with the disappearance or emergence of Raman active reactants, intermediates and products. Such spurious cosmic spikes were identified and removed using a novel and fast numerical approach based on maximum and minimum spectral entropy principles while preserving the genuine reaction‐induced spectral variations. Subsequently, the band‐target entropy minimization (BTEM) algorithm, a minimum spectral entropy based self‐modeling curve resolution technique, was applied to recover the pure component spectra of Raman active chemical species. Information gain through the chemometric analyses was calculated using information entropies with base 2 logarithm. This sequence of information‐theoretic chemometric analyses (or transinformations) was successfully tested on the reaction spectral data obtained from alcoholysis of acetic anhydride, which contains four Raman active chemical species. It is envisioned that this series of multivariate statistical analyses will be useful in chemical reaction studies and process analytical technology (PAT) applications that utilize in situ Raman spectroscopy to monitor transient dynamic changes in chemical concentrations, and also in Raman microscopy/imaging data containing spatial variations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
83.
84.
The potential of electrospun pullulan/dextran (P/D) nanofibers (average diameter = 323 nm) for vascular tissue engineering applications is explored. The mechanical properties of the nanofibers are of the same order of magnitude as that of human arteries (Young's modulus ≈0.88 MPa; tensile strength ≈0.35 MPa). It is demonstrated that the nanofiber topography enables cell adhesion and that the endothelial phenotype is maintained on the nanofibers. Moreover, P/D nanofibers support a stable confluent monolayer of endothelial cells over 14 d. SMCs seeded on nanofibers display similar levels of alpha smooth muscle actin and a lower proliferation rate than cells on 2D cultures. The observations suggest that nanofibers promote a shift to a quiescent contractile phenotype in SMCs.
85.
By introducing an additional hydrogen bond to hydrogen bond interaction in the force field of the CSAW (Conditioned Self-Avoiding
Walk) model, we investigate into the mechanism of antiparallel β-sheet formation based on the folding of a short polyalanine in gas phase. Through our numerical simulation, we detect the
possible presence of a transient helix during β-sheet formation, whose presence is shown to have slowed the formation of β-sheets by an order of magnitude. While we observe the mechanisms of nucleation, zipping and induction that drives the formation
of a β-sheet, we uncover a new mechanism that involves transient β-turns and short β-sheets during the formation of long β-sheets. Our results have enabled us to provide an overview on the mechanisms of β-sheet formation via two main folding pathways: slow folding through the intermediate state of transient helix, and fast folding
from the nucleation of β-turn. 相似文献
86.
87.
Norwahyu Jusoh Thiam Leng Chew Kok Keong Lau Azmi Mohd Shariff 《Separation & Purification Reviews》2016,45(4):321-344
In the early stage of membrane technology development in gas separation, utilization of polymeric membranes has gained attention due to their robustness and ease of fabrication. However, the performance of polymeric membranes is limited by the trade-off between permeability and selectivity. Meanwhile, inorganic membrane is capable to exhibit great enhancement in separation performance but unfortunately its fabrication process is hard and costly. Thus, development of mixed matrix membranes (MMMs) by incorporating inorganic fillers into the polymer matrix has become a potential alternative to overcome the limitations of polymeric and inorganic membranes in gas separation. Nevertheless, fabrication of defect-free MMMs with improved separation performance and without compromising the mechanical and thermal stability is extremely difficult and challenging. In the current review paper, various types of inorganic fillers for MMMs fabrication and recent reported efforts to tailor the underlying problems on MMMs fabrication were discussed. The future outlook to advance the performance of MMMs in gas separation especially for CO2/CH4 separation was highlighted. 相似文献
88.
The development of an interactive simulation program generator which is available on micro and mainframe computers is outlined. The generator forms part of a simulation environment being researched into and constructed by a group of researchers at the London School of Economics. The generated programs are written in Pascal, using a suite of routines which assume a three-phase structure for simulation programs. Experiences of modelling using such a simulation modelling environment are outlined, as well as details of related research and future research plans. 相似文献
89.
A New Differential Lattice Boltzmann Equation and Its Application to Simulate Incompressible Flows on Non-Uniform Grids 总被引:1,自引:0,他引:1
A new differential lattice Boltzmann equation (LBE) is presented in this work, which is derived from the standard LBE by using Taylor series expansion only in spatial direction with truncation to the second-order derivatives. The obtained differential equation is not a wave-like equation. When a uniform grid is used, the new differential LBE can be exactly reduced to the standard LBE. The new differential LBE can be applied to solve irregular problems with the help of coordinate transformation. The present scheme inherits the merits of the standard LBE. The 2-D driven cavity flow is chosen as a test case to validate the present method. Favorable results are obtained and indicate that the present scheme has good prospects in practical applications. 相似文献
90.
In vivo sodium-23 magnetic resonance surface coil imaging: Observing experimental cerebral ischemia in the rat 总被引:2,自引:0,他引:2
Michael E. Moseley Ph.D. Wil M. Chew B.S. Merry C. Nishimura B.S. Todd L. Richards Ph.D. Joseph Murphy-Boesch Ph.D. Gregory B. Young Ph.D. Thomas M. Marschner Ph.D. Lawrence H. Pitts M.D. Thomas L. James Ph.D. 《Magnetic resonance imaging》1985,3(4):383-387
Sodium-23 magnetic resonance imaging can be used to detect and assess experimental cerebral ischemia in the rat. An imaging technique utilizing a surface coil is described to produce sodium magnetic resonance images of good quality and resolution within 10 min. A novel method of hemispheric occlusion showed edema in the right brain of the rat head within 3 hr after injury. The edema was especially pronounced by 12 hr with effects in the right brain, eye and surrounding muscle evident. 相似文献