一种新颖的自动调压交流稳压电源

提出了一种新型无触点有载调压变压器,分析了它的工作原理,并提出采用该新型变压器组成自动调压交流稳压电源的新思路     

Contextual regularity and complexity of neuronal activity: From stand‐alone cultures to task‐performing animals

Precursors of the superior information processing capabilities of our cortex can most probably be traced back to simple invertebrate systems. Using a unique set of newly developed neuronal preparations and state‐of‐the‐art analysis tools, we show that insect neurons have the ability to self‐regulate the information capacity of their electrical activity. We characterize the activity of a distinct population of neurons under progressive levels of structural and functional constraints: self‐formed networks of neuron clusters in vitro; isolated ex vivo ganglions; in vivo task‐free, and in vivotask‐forced neuronal activity in the intact animal. We show common motifs and identify trends of increasing self‐regulated complexity. This important principle may have played a key role in the gradual transition from simple neuronal motor control to complex information processing. © 2004 Wiley Periodicals, Inc. Complexity 9: 25–32, 2004     

On mixed Abelian groups with periodic groups of automorphisms

In the paper, sufficient conditions for the splittability of mixed Abelian groups with periodic automorphism groups are established. Classes of mixed splittable Abelian groups with perfect holomorphs are distinguished. Translated fromMaternaticheskie Zametki, Vol. 61, No. 4, pp. 483–493, April, 1997. Translated by A. I. Shtern     

测定苷甲对ERK激酶活性影响的三种方法比较

细胞外信号调节蛋白激酶(ERK)在细胞生长、分裂、恶性转化、凋亡等过程中起重要作用.土贝母苷甲(下称苷甲)是从传统中药土贝母块茎中分离出来的一种三萜皂苷.该研究分别用放射自显影、液闪和蛋白免疫印迹法检测苷甲对ERK激酶活性的影响.结果表明,苷甲能快速激活ERK.三种检测ERK激酶活性的方法各有短长.     

Riemann积分中几个常用的可积充分条件的统一

根据教学实践,提出用正规函数的可积性统一Riemann积分常用的几个可积充分条件的观点,用Darboux理论证明了正规函数的可积性．     

实用农作物生长调控专家系统的设计与实现

介绍了农作物生长调控专家系统的设计原理、开发原则、开发环境,系统组成和结构设计,并以农业专家系统开发平台为PAID4.0为开发平台,给出了实用农作物生长调控专家系统的设计实例.     

正则区域的对数导数单叶性内径

研究了单位圆到正则区域的共形映射的对数导数,讨论了对数导数范数的一些性质,得到了带凸角的正则区域在对数导数意义下的单叶性内径的一个下界估计,并推导出椭圆内部区域的对数导数意义下的单叶性内径为1.     

ERK_(1,2)抑制剂联合5-FU对B16细胞增殖和凋亡的影响

目的:观察ERK_(1,2)抑制剂联合5-Fu对B16细胞增殖和凋亡的影响,并探讨作用机制.方法:用MTT法观察ERK_(1,2)抑制剂、5-FU和联合用药对细胞增殖的抑制作用,流式细胞仪检测细胞凋亡率,用RT-PCR观察ERK_(1,2)抑制剂、5-Fu和联合用药对bcl-2和caspase-9的表达的影响.结果:ERK_(1,2)抑制剂联合5-Fu组在抑制细胞增殖,诱导细胞凋亡,均较对照组、单独用药组作用增强,并且下调bcl-2和上调easpase-9的表达.结论:ERK_(1,2)抑制剂联合5-Fu有协同抑制B16细胞增殖,促进凋亡的作用,其机制可能与诱导细胞凋亡,下调bcl-2和上调caspase-9的表达有关.     

TH—SZB型数字系统设计实验箱电源保护电路的改进

对TH—SZB型数字系统设计实验箱直流电源保护部分存在的不足进行了分析,提出了一种新型电源保护的方法,利用该方法对实验箱直流稳压电源的过流保护电路进行了改造,改造后的实验箱大大减少了实验过程中的意外损失,并提高了工作效率。     

On electrophoresis of a pH‐regulated nanogel with ion partitioning effects

The electrophoresis of a polyelectrolyte nanoparticle, whose charge condition depends on the salt concentration and pH of the suspended medium as well as the dielectric permittivity difference, is analyzed. The present nonlinear model for the electrophoresis of this pH‐regulated polyelectrolyte (PE) particle is based on the consideration of full set of governing equations of fluid and ion transport coupled with the equation for electric field. The Born energy of the ions are incorporated to account for the difference in the dielectric permittivity of the PE and the electrolyte. The governing equations are computed numerically through a control volume approach. The nonlinear effects are highlighted by comparing with the existing linear model as well as results based on the first‐order perturbation analysis valid for a weak applied field. The ion partitioning effect arising due to the difference in self energy of ions between the two media, have a strong impact on the mobility of the PE. The ion partitioning effect attenuates the penetration of counterions in the PE, which enhances the electric force and hence, results in a larger mobility of the PE. The nonlinear effects due to the double layer polarization and relaxation are intensified due to the ion partitioning effect. The ion partitioning effect influences the association/dissociation of PE functional group by tuning the hydrogen/hydroxide ions. Present study shows that the ion partitioning effect is profound for higher salt concentration and/or higher volume density of PE functional groups.