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41.
Zelong Gong Xuefeng Gao Qingqing Yang Jingxian Lun Hansen Xiao Jiayu Zhong Hong Cao 《Molecules (Basel, Switzerland)》2022,27(13)
Enterovirus 71 (EV71) is a dominant pathogenic agent that may cause severe central nervous system (CNS) diseases among infants and young children in the Asia-pacific. The inflammasome is closely implicated in EV71-induced CNS injuries through a series of signaling pathways. However, the activation pathway of NLRP3 inflammasome involved in EV71-mediated CNS injuries remains poorly defined. In the studies, EV71 infection, ERK1/2 phosphorylation, and activation of NLRP3 are abolished in glioblastoma cells with low vimentin expression by CRISPR/Cas9-mediated knockdown. PD098059, an inhibitor of p-ERK, remarkably blocks the vimentin-mediated ERK1/2 phosphorylation in EV71-infected cells. Nuclear translocation of NF-κB p65 is dependent on p-ERK in a time-dependent manner. Moreover, NLRP3 activation and caspase-1 production are limited in EV71-infected cells upon the caffeic acid phenethyl ester (CAPE) administration, an inhibitor of NF-κB, which contributes to the inflammasome regulation. In conclusion, these results suggest that EV71-mediated NLRP3 inflammasome could be activated via the VIM-ERK-NF-κB pathway, and the treatment of the dephosphorylation of ERK and NF-κB inhibitors is beneficial to host defense in EV71-infected CNS. 相似文献
42.
Computer-generated binary holograms are written on a polished copper surface using single 800-nm, 120-fs pulses from a 1-kHz-repetition-rate laser system. The hologram efficiency (i.e. the power in the holographic reconstructed image relative to the incoming laser power) is investigated for different laser-structuring parameters. Theoretical diffraction grating efficiencies for a binary amplitude grating show good agreement with the experimental measurements for diameters of the laser-formed holes below the pitch. Modelling based on straightforward geometrical arguments is used to find the optimal hole size. For a coverage (i.e. relative laser-structured area) of ~43 %, the efficiency reaches ~10 %, which corresponds to a relative power transferred to one reconstructed image of ~20 %. The efficiency as a function of pitch (for fixed coverage) is fairly constant from 2 to 6 μm. 相似文献
43.
44.
M. Fechner F. Reichert N.-O. Hansen K. Petermann G. Huber 《Applied physics. B, Lasers and optics》2011,102(4):731-735
Polarization dependent ground state absorption, excited state absorption and emission cross sections of Pr,?Mg:SrAl12O19 are determined in the visible and ultraviolet spectral region. It is shown that excited state absorption to the 4f5d configuration does neither occur on the pump wavelength in the blue region nor on any of the visible laser transitions. Efficient laser action at 643.5?nm is demonstrated with slope efficiencies of up to 47% with respect to the absorbed pump power. Output powers up to 75?mW are achieved by pumping with an InGaN laser diode at 444?nm. 相似文献
45.
46.
T.P. Leervad Pedersen J. Skov Jensen J. Chevallier O. Hansen J.M. Jensen B. Bech Nielsen A. Nylandsted Larsen 《Applied Physics A: Materials Science & Processing》2005,81(8):1591-1593
The synthesis of evenly distributed Ge nanoclusters in plasma-enhanced chemical-vapour-deposited (PE-CVD) SiO2 thin films containing 8 at. % Ge is reported. This is of importance for the application of nanoclusters in semiconductor
technology. The average diameter of the Ge nanoclusters can be controlled in the range of 3–6 nm by variation of the annealing
parameters. Using a combination of transmission electron microscopy and Raman-scattering spectroscopy, the nanoclusters were
shown to be crystalline. However, photoluminescence measurements showed no light emission that could be definitively correlated
to the presence of the nanoclusters.
PACS 61.82.Rx; 78.67.Bf; 81.07.Bc 相似文献
47.
New experimental data for the transmission loss of plenum chambers are compared to results obtained using several different and well known prediction models. Results for transmission loss as a function of frequency in 1/3 octave bands are presented for a series of plenum chamber configurations of various sizes and interior acoustical treatments. In the experimental work the transmission loss was determined from simultaneous measurements at two upstream and two downstream microphones. 相似文献
48.
Stefano Bernardi J. S. Hansen Federico Frascoli B. D. Todd Carl P. Dettmann 《Journal of statistical physics》2012,148(6):1156-1169
We analyze the dynamics of a gas particle moving through a nanopore of adjustable width with particular emphasis on ergodicity. We give a measure of the portion of phase space that is characterized by quasiperiodic trajectories which break ergodicity. The interactions between particle and wall atoms are mediated by a Lennard-Jones potential, so that an analytical treatment of the dynamics is not feasible, but making the system more physically realistic. In view of recent studies, which proved non-ergodicity for systems with scatterers interacting via smooth potentials, we find that the non-ergodic component of the phase space for energy levels typical of experiments, is surprisingly small, i.e. we conclude that the ergodic hypothesis is a reasonable approximation even for a single particle trapped in a nanopore. Due to the numerical scope of this work, our focus will be the onset of ergodic behavior which is evident on time scales accessible to simulations and experimental observations rather than ergodicity in the infinite time limit. 相似文献
49.
Á. Nemcsics L. Tóth L. Dobos Ch. Heyn A. Stemmann A. Schramm H. Welsch W. Hansen 《Superlattices and Microstructures》2010
Self-assembled strain-free quantum dot (QD) structures were grown on AlGaAs surface by the droplet epitaxal method. The QDs were developed from pure Ga droplets under As pressure. The QDs were investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM). Both techniques show that the QDs are very uniform in size and their distribution on the surface is also homogeneous. The high resolution cross-sectional TEM investigation shows perfect lattice matching between the QD and the substrate, and also the faceting of the side walls of QD can be identified exactly by lattice planes. Analytical TEM (elemental mapping by EELS) unambiguously identifies the presence of Al in the QD. 相似文献
50.