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81.
Despite phenomenal clinical success, the efficacy of platinum anticancer drugs is often compromised due to inherent and acquired drug resistant phenotypes in cancers. To circumvent this issue, we designed two heterobimetallic platinum (II)-ferrocene hybrids that display multi-pronged anticancer action. In cancer cells, our best compound, 2 , platinates DNA, produces reactive oxygen species, and has nucleus, mitochondria, and endoplasmic reticulum as potential targets. The multi-modal mechanism of action of these hybrid agents lead to non-apoptotic cell death induction which enables circumventing apoptosis resistance and significant improvement in platinum cross resistance profile. Finally, in addition to describing detail mechanistic insights, we also assessed its stability in plasma and demonstrate anticancer efficacy in an in vivo A2780 xenograft model. Strikingly, compared to oxaliplatin, our compound displays better tolerability, safety profile and efficacy in vivo.  相似文献   
82.
The propagation and interaction between ion acoustic multi-solitons in an unmagnetized multicomponent plasma consisting of fluid hot ions, positrons and both hot and cold electrons, are investigated by employing the extended Poincare–Lighthill–Kuo(PLK) method. Two different Kortewege-de Vries(K-dV) equations are derived. The Hirota's method is applied to get the K-dV multi-solitons solution. The phase shift due to the overtaking and head- on collision of the multi-solitons is obtained.  相似文献   
83.
The present work attempts to identify the roles of flow and geometric variables on the scaling factor which is a necessary parameter for modeling the apparent viscosity of non-Newtonian fluid in porous media. While idealizing the porous media microstructure as arrays of circular and square cylinders, the present study uses multi-relaxation time lattice Boltzmann method to conduct pore-scale simulation of shear thinning non-Newtonian fluid flow. Variation in the size and inclusion ratio of the solid cylinders generates wide range of porous media with varying porosity and permeability. The present study also used stochastic reconstruction technique to generate realistic, random porous microstructures. For each case, pore-scale fluid flow simulation enables the calculation of equivalent viscosity based on the computed shear rate within the pores. It is observed that the scaling factor has strong dependence on porosity, permeability, tortuosity and the percolation threshold, while approaching the maximum value at the percolation threshold porosity. The present investigation quantifies and proposes meaningful correlations between the scaling factor and the macroscopic properties of the porous media.  相似文献   
84.
For the p-variate Poisson mean, under the sum of weighted squared error losses, weights being reciprocals of variances, a class of proper Bayes minimax estimates dominating the usual estimate, namely the sample mean is produced. An example is given to illustrate this. The interrelation of our results with those of Clevenson and Zidek is pointed out.  相似文献   
85.
Ni‐diamond composite coatings with high concentration and uniform distribution of diamond particles were prepared by using sediment co‐deposition (SCD) technique from Watts‐type electrolyte without any additives. The surface and cross‐section morphology was evaluated by optical microscope (OM) and scanning electron microscopy (SEM). It was demonstrated that the Ni‐monolayer diamond composite coatings ~40 ± 5 µm was successfully prepared by the new developed setup for SCD technique. Using this new developed setup, high concentration and uniform distribution of diamond particles of Ni‐monolayer diamond composite coatings were easily fabricated. The wear resistance and cutting performance of obtained composite coatings were also investigated. The results revealed that anti‐wear and cutting performance is superior to those prepared via conventional co‐electrodeposition (CED) technique and pure Ni coatings. In the SCD process, with the increasing diamond content, the wear resistance is approximately the same, and the cutting performance decreases. Therefore, not only the diamond particle content is responsible for the wear resistance and cutting performance, the distribution of diamond particles is also very important factor. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The paper reports a detailed analysis of the chaotic dynamics of a theoretical model of a time delayed semi conductor laser. The periodic, quasi-periodic and chaotic nature is investigated with phase-plots, bifurcation analysis and lyapunov exponents. The effect of the system when induced by colored and bounded sine-Wiener noise has been examined extensively. The nature of the noise-induced propagating waves is investigated with the help of wavelet power spectra. It has been observed that the additive noise can suppress the chaotic dynamics of the system. Also the system is more chaotic in the presence of multiplicative noise. Moreover, the additive and multiplicative noise can modulate the output power upto a certain level, with constant input parameters.  相似文献   
89.
A convenient synthesis of azidomethyl-ruthenocene and its use in the covalent labelling of amino acids, peptides and a peptide nucleic acid (PNA) monomer derivative by Cu(I) catalyzed azide-alkyne coupling (Cu-AAC, "click chemistry") are described.  相似文献   
90.
Mesoporous iron phosphate (FePO4) was synthesized through assembly of polymeric micelles made of asymmetric triblock co‐polymer (polystyrene‐b‐poly‐2‐vinylpyridine‐b‐ethylene oxide; PS‐PVP‐PEO). The phosphoric acid solution stimulates the formation of micelles with core–shell‐corona architecture. The negatively charged PO43? ions dissolved in the solution strongly interact with the positively charged PVP+ units through an electrostatic attraction. Also, the presence of PO43? ions realizes a bridge between the micelle surface and the metal ions. The removal of polymeric template forms the robust framework of iron phosphate with 30 nm pore diameter and 15 nm wall thickness. Our method is applicable to other mesoporous metal phosphates by changing metal sources. The obtained materials were fully characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), N2 adsorption–desorption, Raman spectroscope, and other techniques.  相似文献   
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