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921.
Dr. Qicai Xiao Dr. Wei Du Dr. Xiao Dong Dr. Shubo Du Sing Yee Ong Dr. Guanghui Tang Dr. Changyu Zhang Dr. Fen Yang Prof. Dr. Lin Li Prof. Dr. Liqian Gao Prof. Dr. Shao Q. Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(47):12207-12214
Mitochondria are key organelles that perform vital cellular functions such as those related to cell survival and death. The targeted delivery of different types of cargos to mitochondria is a well-established strategy to study mitochondrial biology and diseases. Of the various existing mitochondrion-transporting vehicles, most suffer from poor cytosolic entry, low delivery efficiency, limited cargo types, and cumbersome preparation protocols, and none was known to be universally applicable for mitochondrial delivery of different types of cargos (small molecules, proteins, and nanomaterials). Herein, two new cell-penetrating, mitochondrion-targeting ligands (named MitoLigand) that are capable of effectively “tagging” small-molecule drugs, native proteins and nanomaterials are disclosed, as well as their corresponding chemoselective conjugation chemistry. Upon successful cellular delivery and rapid endosome escape, the released native cargos were found to be predominantly localized inside mitochondria. Finally, by successfully delivering doxorubicin, a well-known anticancer drug, to the mitochondria of HeLa cells, we showed that the released drug possessed potent cell cytotoxicity, disrupted the mitochondrial membrane potential and finally led to apoptosis. Our strategy thus paves the way for future mitochondrion-targeted therapy with a variety of biologically active agents. 相似文献
922.
Shao Su Xinpan Wei Yuanyuan Guo Yiling Zhong Yuanyuan Su Qing Huang Chunhai Fan Yao He 《Particle & Particle Systems Characterization》2013,30(4):326-331
A new kind of silicon nanowire (SiNWs)‐based nanoelectrode assembly, a gold‐nanoparticle‐decorated silicon nanowire array (AuNPs@SiNWsAr), is employed for the construction of high‐performance electrochemical sensors. Significantly, the electrochemical nanosensors are capable of sensitive detection of various electroactive molecules (e.g., dopamine (DA), ascorbic acid (AA), hydrogen peroxide (H2O2), and glucose). Further, DA molecules loaded on the surface of AuNPs@SiNWsAr preserve stable high electroactivity overnight without special protection, while free DA molecules may lose their biological activity due to severe oxidization in ambient environment. These findings may offer new opportunities for the design of high‐performance electrochemical nanosensors with high sensitivity and robust stability. 相似文献
923.
<正>Low-dielectric-constant poly(acetoxystyrenezhi-co-octavinyl-polyhedral oligomeric silsesquioxane)(PAS-POSS) organicinorganic hybrid nanocomposite was successfully synthesized via one-step free radical polymerization and characterized by FTIR,high-resolution ~1H NMR,~(29)Si NMR,DSC,TGA,AFM,spectroscopic elhpsometry and dielectric constants measurements. The results show T_g and T_(dec) were elevated dramatically due to the incorporation of inorganic POSS cores.Spectroscopic ellipsometry and dielectric constants measurement display the incorporation of POSS into PAS homopolymer can apparently reduce the dielectric constant of materials due to the increase of relative porosity of the hybrid nanocomposites. 相似文献
924.
This paper proposes a block Arnoldi method for parameterized model order reduction. This method works when design parameters have only low-rank impacts on the system matrix. The method preserves all design parameters in the reduced model and is easy to implement. Numerical results show that the block Arnoldi process outperforms some existing methods up to a factor of ten. 相似文献
925.
C. H. Yao S. F. Zhao J. R. Li Y. W. Mu J. G. Wan M. Han G. H. Wang 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(2):197-205
The lowest-energy geometries and electronic-structure properties have been
obtained for AlnHn (n=1-10) clusters within the
density-functional theory using the generalized gradient approximation for
the exchange correlation potential. The resulting geometries show that the
hydrogen atoms tend to occupy outside positions and no hollow positions are
found. The subunit Aln of AlnHn (n=1-5) have little
distortion, in comparison with corresponding pure Aln cluster, whereas
the subunit Aln have large distortion from n=6. The stability has been
investigated by analyzing the binding energy per atom and the second
difference in energy, indicating that Al8H8 exhibit higher
stability than others. The bonding property has been analyzed by calculating
the Mulliken charges and Al–H distances. The calculated energy gap between
the highest occupied molecular orbital and the lowest unoccupied molecular
orbital (HOMO-LUMO), the vertical ionization potential, and the vertical
electron affinity also confirm that Al8H8 is a stable cluster. The
density of states (DOS) shows that AlnHn exhibit changes from
molecular-like (Al1H1) to band-like structure (Al10H10)
as n increases. 相似文献
926.
Y.-K. Kuo S.-H. Yen M.-W. Yao M.-C. Tsai M.-L. Chen B.-T. Liou 《Applied physics. B, Lasers and optics》2008,93(2-3):497-506
In this work, the multiple-quantum-well InGaAsN laser structures with indirect-GaAsP and direct-GaAsN barriers are investigated by using LASTIP simulation program. We vary the quantum-well number, from 1 to 5, to find appropriate barrier material for InGaAsN laser structures. The simulation results show that InGaAsN laser structure has higher characteristic temperature regardless of what quantum-well number is if the indirect-GaAsP barrier is utilized. Furthermore, for InGaAsN laser structure, the usage of indirect-GaAsP barrier is beneficial for reducing the threshold current when the quantum-well number is from 1 to 2 and the usage of direct-GaAsN barrier is beneficial for reducing the threshold current when the quantum-well number is from 3 to 5. 相似文献
927.
Zhongbing Huang Xiaoming Liao Yunqing Kang Guangfu Yin Yadong Yao 《Journal of colloid and interface science》2009,330(2):399-403
Why is it that drops do not slip down inclined thin fibers or spider silks? The possible explanation is based on the existence of fiber size, which causes a sustaining force that pins these drops. Following this explanation, the drop remains in equilibrium until a critical value of the sustaining force is reached. We suggest an alternative analyses, from the point of view of the inclined fiber at which the drop slips down is predicted. This result does not depend explicitly on silk surface roughness, but only on the drop size and surface tensions. 相似文献
928.
Bangben Yao 《Tetrahedron letters》2008,49(37):5385-5388
In the presence of triflic anhydride, sulfonylation of arenes with sulfonamides proceeded smoothly in Cl2CHCHCl2 at 80-140 °C, which gave rise to the desired products in good to excellent yields. 相似文献
929.
This work presents a theoretical analysis for the Black–Scholes equation. Given a terminal condition, the analytical solution of the Black–Scholes equation is obtained by using the Adomian approximate decomposition technique. The mathematical technique employed in this work also has significance in studying some other problems in finance theory. 相似文献
930.
This is a continuation of the article(Comm.Partial Differential Equations 26(2001)965).In this article,the authors consider the one-dimensional compressible isentropic Navier-Stokes equations with gravitational force,fixed boundary condition,a general pressure and the density-dependent viscosity coefficient when the viscous gas connects to vacuum state with a jump in density.Precisely,the viscosity coefficient μ is proportional to ρ^θ and 0〈θ〈1/2,where ρ is the density,and the pressure P=P(ρ)is a general pressure.The global existence and the uniqueness of weak solution are proved. 相似文献