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81.
Richard Kuan-Lin Lee Tian-Neng Li Sui-Yuan Chang Tai-Ling Chao Chun-Hsien Kuo Max Yu-Chen Pan Yu-Ting Chiou Kuan-Ju Liao Yi Yang Yi-Hsuan Wu Chen-Hao Huang Hsueh-Fen Juan Hsing-Pang Hsieh Lily Hui-Ching Wang 《International journal of molecular sciences》2022,23(7)
Entry inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are urgently needed to control the outbreak of coronavirus disease 2019 (COVID-19). This study developed a robust and straightforward assay that detected the molecular interaction between the receptor-binding domain (RBD) of viral spike protein and the angiotensin-converting enzyme 2 (ACE2) receptor in just 10 min. A drug library of 1068 approved compounds was used to screen for SARS-CoV2 entry inhibition, and 9 active drugs were identified as specific pseudovirus entry inhibitors. A plaque reduction neutralization test using authentic SARS-CoV-2 virus in Vero E6 cells confirmed that 2 of these drugs (Etravirine and Dolutegravir) significantly inhibited the infection of SARS-CoV-2. With molecular docking, we showed that both Etravirine and Dolutegravir are preferentially bound to primary ACE2-interacting residues on the RBD domain, implying that these two drug blocks may prohibit the viral attachment of SARS-CoV-2. We compared the neutralizing activities of these entry inhibitors against different pseudoviruses carrying spike proteins from alpha, beta, gamma, and delta variants. Both Etravirine and Dolutegravir showed similar neutralizing activities against different variants, with EC50 values between 4.5 to 5.8 nM for Etravirine and 10.2 to 22.9 nM for Dolutegravir. These data implied that Etravirine and Dolutegravir may serve as general spike inhibitors against dominant viral variants of SARS-CoV-2. 相似文献
82.
L.M. Wang Ching-Yu ChangShau-Tin Yeh Shinn Wei ChenZi An Peng Shun Chang BairD.S. Lee F.C. LiaoY.K. Kuo 《Ceramics International》2012,38(2):1167-1174
The synthesis and transport properties of n-type thermoelectric oxide (ZnO)mIn2O3 (ZmIO) ceramics prepared by conventional solid-state reaction method have been reported. It is found that the transport properties of ZmIO ceramics are very sensitive to the post-annealing temperature as well as the zinc content m. The resistivity of Z5IO annealed at 1400 °C decreases by more than 2 orders of magnitude in comparison with that of Z5IO annealed at 1200 °C, while the resistivities of Z6IO compounds annealed at 1250 and 1350 °C are more than 3 orders of magnitude larger than that of Z6IO annealed at 1300 °C. All the ZmIO compounds annealed at 1300 °C show electron-type conduction with a lowest resistivity at m = 6. It is suggested that the oxygen defects or vacancies in the InO2 layers play a major role on the carrier scattering mechanism, and the observed temperature-dependent resistivity for Z5IO and Z6IO compounds can be satisfactorily described by the variable-range hopping conduction. Furthermore, it is found that the values of Seebeck coefficient for ZmIO are also very sensitive to the zinc content m. The dimensionless figure of merit of 0.0045 at 300 K for m = 6 has been obtained. 相似文献
83.
Transesterification cure in coatings can be catalyzed by an alkoxide which is formed during bake by the combination of an epoxide with a nucleophile. Support for transesterification cure in the presence of epoxides and nucleophiles has been provided by FTIR evolved gas analysis (EGA/FTIR) and thermal gravimetric analysis (TGA). Effective nucleophiles include tertiary amines, certain inorganic nucleophiles like cyanide, hydroxide and azide, and quaternary ammonium salts. Quaternary ammonium carboxylates are particularly effective nucleophile sources for this cure chemistry, especially those that have better thermal stability. EGA/FTIR was used to demonstrate differences in the thermal stability of quaternary ammonium salts, and these differences were correlated with differences in cure at higher bake temperatures. Transesterification cure of hydroxyl functional acrylics can provide greatly improved impact resistance if the acrylics are blended with polyesters. Dynamic mechanical analysis (DMA) has shown differences between acrylic and acrylic-polyester blends which may help to explain the differences in impact resistance. 相似文献
84.
85.
Polycarbonate (PC) nanofibers are prepared using the air blowing‐assisted electrospinning process. The effects of air blowing pressure and PC solution concentration on the physical properties of fibers and the filtration performance of the nanofiber web are investigated. The air blowing‐assisted electrospinning process produces fewer beads and smaller nanofiber diameters compared with those obtained without air blowing. Uniform PC nanofibers with an average fiber diameter of about 0.170 μm are obtained using an applied voltage of 40 kV, an air blowing pressure of 0.3 MPa, a PC solution concentration of 16%, and a tip‐to‐collection‐screen distance (TCD) of 25 cm. The filtration efficiency improvement of the air blowing‐assisted electrospun web can be attributed to the narrow distribution of fiber diameter and small mean flow pore size of the electrospun web. Performance results show that the air blowing‐assisted electrospinning process can be applied to produce PC nanofiber mats with high‐quality filtration. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
86.
Synthesis and characterizations of a vinyl-terminated benzoxazine monomer and its blending with polyhedral oligomeric silsesquioxane (POSS) 总被引:4,自引:0,他引:4
Benzoxazine was synthesized through the Mannich condensation of phenol, formaldehyde, and primary amines through ring-opening polymerization. Polybenzoxazines are phenolic-like materials that possess dimensional and thermal stability, and they release no toxic byproducts during their polymerization. To further improve the thermal stability of polybenzoxazines, a hydrosilane-functionalized polyhedral oligomeric silsesquioxane (H-POSS) was incorporated into the vinyl-terminated benzoxazine monomer (VB-a) which we then subjected to ring-opening polymerization. In addition, we also prepared hybrids from a non-reactive POSS (IB-POSS) and VB-a. The glass transition temperature (Tg) of a regular polymerized VB-a (i.e. PVB-a) is 307 °C, while the hybrid containing 5 wt% of H-POSS is 333 °C. The IB-POSS modified PVB-a hybrids, in general, results in lower Tg than the pure PVB-a due to poor missibility. 相似文献
87.
An amphoteric water‐soluble copolymer, that is, polyacrylamide/(α‐N,N‐dimethyl‐N‐acryloyloxyethyl)ammonium ethanate (PAAM/DAAE) was synthesized and it showed the ability to disperse BaTiO3 (BT) particles in aqueous solutions. In this work, the effect of molecular weight of this polymer on the dispersing properties was further examined. The results indicate that the effectiveness of three polymer samples with different molecular weights in the dispersion of BT particles is P2 (Mw = 1.1 × 105) > P1 (Mw = 1.2 × 104) > P3 (Mw = 3.0 × 105). Apparently, P2 is most effective in dispersing the particles, reducing the viscosity of the suspensions, and obtaining highest green and sintered densities. This is attributed to the highest adsorption of this polymer onto BT powder, and causes strongest electrostatic and steric repulsions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 886–891, 2006 相似文献
88.
提出了一种基于颜色特征的运动目标匹配方法。通过颜色直方图定义了运动目标的主颜色区域,并依据最大隶属度原则建立RGB三维彩色空间主颜色区域信息的模糊子集,最后采用模糊相似匹配原理对匹配目标与待匹配目标模糊集的模糊隶属度函数和贴近度函数进行比较,得出匹配结果。实验结果表明,该方法在解决视频监控中运动目标匹配问题时是可行且可靠的。 相似文献
89.
Kuo‐Chen Huang 《Journal of the Society for Information Display》2010,18(5):368-375
Abstract— The effects of velocity (3, 5, and 7 cm/sec), stimulus color (red, green, and blue), and background luminance (20–80% white, in increments of 15%) on minimal legible size of dynamic Chinese characters, were examined. Participants were divided into low‐vision, severely myopic, and normal‐vision groups. They were asked to recognize the stimulus Chinese characters, which were presented with varying velocity on a screen. Analysis showed that the minimal legible size was significantly greater for those in the low‐vision and severely myopic groups than for those in the normal‐vision group, and the minimal legible size for the low‐vision group was greater than that for the severely myopic group. The minimal legible size was significantly greater when the stimuli were green than when they were red or blue; however, no significant difference was found between green and blue stimuli or between blue and red ones. An effect was observed for background luminance: a higher ratio of white in the gray background yielded a smaller minimal legible size than did a lower ratio of white. Additionally, velocity significantly affected the minimal legible size: a velocity of 3 cm/sec resulted in lower minimal legible size than did a velocity of 7 cm/sec. Results have implications for electronic text information design or icon design for visually impaired individuals. 相似文献
90.
Li P.-Y. Sheybani R. Gutierrez C. A. Kuo J. T. W. Meng E. 《Journal of microelectromechanical systems》2010,19(1):215-228