Nanoparticle-Decorated Biomimetic Extracellular Matrix for Cell Nanoencapsulation and Regulation

Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN²). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN² is a promising platform for advancing cell-based applications.     

Uniqueness of Generalized Solutions for a Quasilinear Degenerate Parabolic System

In this paper we study the uniqueness of generalized solutions for a class of quasilinear degenerate parabolic systems arising from dynamics of biological groups. The results obtained give an answer to a problem posed by A.S. Kalashnikov [1].     

A Usual G‐Protein‐Coupled Receptor in Unusual Membranes

G‐protein‐coupled receptors (GPCRs) are the largest family of membrane‐bound receptors and constitute about 50 % of all known drug targets. They offer great potential for membrane protein nanotechnologies. We report here a charge‐interaction‐directed reconstitution mechanism that induces spontaneous insertion of bovine rhodopsin, the eukaryotic GPCR, into both lipid‐ and polymer‐based artificial membranes. We reveal a new allosteric mode of rhodopsin activation incurred by the non‐biological membranes: the cationic membrane drives a transition from the inactive MI to the activated MII state in the absence of high [H⁺] or negative spontaneous curvature. We attribute this activation to the attractive charge interaction between the membrane surface and the deprotonated Glu134 residue of the rhodopsin‐conserved ERY sequence motif that helps break the cytoplasmic “ionic lock”. This study unveils a novel design concept of non‐biological membranes to reconstitute and harness GPCR functions in synthetic systems.     

双波长分光光度法测定阿丙沙星可溶性粉中阿莫西林、盐酸环丙沙星的含量

应用双波长分光光度法测定阿丙沙星可溶性粉中阿莫西林、盐酸环丙沙星的含量。以pH=5．0的磷酸盐缓冲液为溶剂,在波长229、248、315、400nm处进行测定,阿莫西林的浓度在5．130～25．650μg／mL、盐酸环丙沙星的浓度在4．888～24．440μg／mL范围内分别与其吸光度差值呈良好的线性关系。阿莫西林的回收率为99．30％～100．19％,测定结果的相对标准偏差为0．60％～1．00％(n=5),盐酸环丙沙星的回收率为99．30％～99．86％,测定结果的相对标准偏差为0．84％～1．02％(n=5)。     

Syntheses of MO2 (M=Si, Ce, Sn) nanoparticles by solid-state reactions at ambient temperature

Nano oxides (SiO₂, CeO₂, SnO₂) were successfully synthesized by solid-state reactions at ambient temperature. The nanoparticles were characterized by X-ray powder diffraction, TEM, BET, and TGA-DTA. The SiO₂ particles were also investigated using IR spectra. Effects of calcination on the nanoparticles were studied in this paper. The solid-state reaction technique is a convenient, inexpensive and an effective preparation method of monodisperse oxide nanoparticles in high yield. The mechanisms of the formation of nano materials by solid-state reactions at ambient temperature were primarily investigated.     

Spectrum structure and decay rate estimates on the Landau equation with Coulomb potential

In this paper we first deduce the estimates on the linearized Landau operator with Coulomb potential and then analyze its spectrum structure by using semigroup theory and linear operator perturbation theory. Based on these estimates, we give the precise time decay rate estimates on the semigroup generated by the linearized Landau operator so that the optimal time decay rates of the nonlinear Landau equation follow. In addition, we present a similar result for the non-angular cutoff Boltzmann equation with soft potentials.

     

高分辨NMR中的整形脉冲技术及其应用

在NMR技术中,射频(rf)脉冲的形状一般是描述施加于NMR样品的射频脉冲的振幅和相位与时间的关系。本文拟就射频脉冲的一般形状,基于NMR实验中广泛采用的类型及其优点和局限性等诸多问题作一概括评述,本文还将阐述NMR的实验能力对于谱仪硬件的依赖性,以及讨论借助Varian Unity谱仪系统实施脉冲整形的各种可能选择。     

高功率微波辐射场功率阵列测量装置研制

基于高功率微波辐射场分布积分方法,通过衰减、延迟、合路等技术手段,研制了一套高功率微波辐射场功率阵列测量实验装置。该装置仅利用一台示波器就可以同时测得16个不同点处的高功率微波辐射场波形,由此得到不同点处的功率密度,在辐射天线方向图旋转对称的条件下,利用编写的程序可以迅速求得单次、短脉冲高功率微波源的空间辐射功率,并在X波段相对论返波管高功率微波源功率测试中得到应用,为高功率微波功率测量特别是单次HPM功率测量,提供了一种新的功率测量阵列装置。     

Uncertain linguistic Bonferroni mean operators and their application to multiple attribute decision making

In this paper, we investigate the multiple attribute decision making (MADM) problems with uncertain linguistic information. Motivated by the ideal of Bonferroni mean and geometric Bonferroni mean, we develop two aggregation techniques called the uncertain linguistic Bonferroni mean (ULBM) operator and the uncertain linguistic geometric Bonferroni mean (ULGBM) operator for aggregating the uncertain linguistic information. We study its properties and discuss its special cases. For the situations where the input arguments have different importance, we then define the uncertain linguistic weighted Bonferroni mean (ULWBM) operator and the uncertain linguistic weighted geometric Bonferroni mean (ULWGBM) operator, based on which we develop two procedures for multiple attribute decision making under the uncertain linguistic environments. Finally, a practical example is given to verify the developed approach and to demonstrate its practicality and effectiveness.