Coherent Excitation of Sodium Chloride Nanoparticles

We register stimulated low-frequency Raman scattering (SLFRS) caused by laser-pulse interaction with nanoparticle acoustic vibrations in an ethanol suspension of sodium chloride nanoparticles and measure the SLFRS conversion efficiency and threshold. Frequency shifts of scattered light from the exciting light frequency are situated in the gigahertz range. We show that the frequency shifts increase with decrease in the nanoparticle sizes.     

面向并行设计的局部特征识别技术研究

为支持在并行设计过程中设计特征模型到加工特征模型的逐步转换，提出了局部特征识别的方法．在并行设计中，设计特征模型和加工特征模型通过面名历史图共享零件的实体模型，设计特征的变动通过局部特征识别自动地转换为相应的加工特征．局部特征识别是由基于最小条件子图特征识别方法改进来的，它以零件的局部区域为识别对象，通过搜索匹配局部区域构成的边界模式，识别出该局部区域中所包含的加工特征．局部特征识别方法的特点是只对设计中发生变动的区域进行识别．     

Wavy fronts in reaction-diffusion systems with cross advection

Using a field-theoretic approach, we systematically generalize the usual semiclassical approximation for a harmonically trapped ideal Bose gas in such a way that its range of applicability is essentially extended. With this we can analytically calculate thermodynamic properties even for small particle numbers. In particular, it now becomes possible to determine the critical temperature as well as the temperature dependence of both heat capacity and condensate fraction in low-dimensional traps, where the standard semiclassical approximation is not even applicable.     

Synthesis of Highly Selective Submicromolar Microcystin‐Based Inhibitors of Protein Phosphatase (PP)2A over PP1

Research and therapeutic targeting of the phosphoserine/threonine phosphatases PP1 and PP2A is hindered by the lack of selective inhibitors. The microcystin (MC) natural toxins target both phosphatases with equal potency, and their complex synthesis has complicated structure–activity relationship studies in the past. We report herein the synthesis and biochemical evaluation of 11 MC analogues, which was accomplished through an efficient strategy combining solid‐ and solution‐phase approaches. Our approach led to the first MC analogue with submicromolar inhibitory potency that is strongly selective for PP2A over PP1 and does not require the complex lipophilic Adda group. Through mutational and structural analyses, we identified a new key element for binding, as well as reasons for the selectivity. This work gives unprecedented insight into how selectivity between these phosphatases can be achieved with MC analogues.     

Editorial

Editorial

Editorial     

Variational principles and the effect of a cutoff on population pattern size

The relation between pattern size and maximum population density is obtained for the stationary state of populations living in a refuge surrounded by a hostile environment. The population dynamics is described by reaction–diffusion equations whose kinetic terms display a cutoff. The latter takes into account the discreteness of the population when the population density is small. We employ a variational principle for the nonlinear eigenvalue problem to obtain lower bounds for the pattern length. Numerical solutions display excellent agreement with our analytical results.