p47phox, the phagocyte NADPH oxidase/NOX2 organizer: structure, phosphorylation and implication in diseases

Phagocytes such as neutrophils play a vital role in host defense against microbial pathogens. The anti-microbial function of neutrophils is based on the production of superoxide anion (O₂^•-), which generates other microbicidal reactive oxygen species (ROS) and release of antimicrobial peptides and proteins. The enzyme responsible for O₂^•- production is called the NADPH oxidase or respiratory burst oxidase. This multicomponent enzyme system is composed of two transmembrane proteins (p22phox and gp91phox, also called NOX2, which together form the cytochrome b₅₅₈) and four cytosolic proteins (p47phox, p67phox, p40phox and a GTPase Rac1 or Rac2), which assemble at membrane sites upon cell activation. NADPH oxidase activation in phagocytes can be induced by a large number of soluble and particulate agents. This process is dependent on the phosphorylation of the cytosolic protein p47phox. p47phox is a 390 amino acids protein with several functional domains: one phox homology (PX) domain, two src homology 3 (SH3) domains, an auto-inhibitory region (AIR), a proline rich domain (PRR) and has several phosphorylated sites located between Ser303 and Ser379. In this review, we will describe the structure of p47phox, its phosphorylation and discuss how these events regulate NADPH oxidase activation.     

Synthesis and characterization of thermally stable,high‐modulus polyimides containing benzimidazole moieties

A series of novel benzimidazole‐containing aromatic polyimides were prepared from synthesized 5,4′‐diamino‐2‐phenyl benzimidazole (DAPBI), and commercial dianhydrides by the conventional two‐step polymerization. The obtained films were amorphous and could afford flexible, transparent, and tough films with excellent thermal and mechanical properties. They showed high levels of tension strength of up to 234 MPa, modulus of up to 5.6 GPa without any stretching. According to thermal stability measurements, the glass‐transition temperatures of the polymers were observed between 329 and 425 °C. The 5% weight‐loss temperatures of most polyimides were above 600 °C in nitrogen. Excellent properties of these polyimides were proved to be attributed to the rigid‐rod structure and hydrogen bond of intermacromolecular. SAXS and SEM results showed self‐molecular orientation caused the formation of rod‐like extended conformations. It was demonstrated that high degree of supramolecular order led to the increase of thermal stability and mechanical properties of the polyimide films. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2024–2031, 2009     

Delay model of glucose-insulin systems: Global stability and oscillated solutions conditional on delays

Recently P. Palumbo, S. Panunzi and A. De Gaetano analyzed a delay model of the glucose-insulin system. They proved its persistence, the existence of a unique positive equilibrium point, as well as the local stability of this point. In this paper we consider further the uniform persistence of such equilibrium solutions and their global stability. Using the omega limit set of a persistent solution and constructing a full time solution, we also investigate the effect of delays in connection with the behavior of oscillating solutions to the system. The model is shown to admit global stability under certain conditions of the parameters. It is also shown that the model admits slowly oscillating behavior, which demonstrates that the model is physiologically consistent and actually applicable to diabetological research.     

Fuzzy代数与Fuzzy商代数

本文更深入地讨论了Ｆｕｚｚｙ代数，Ｆｕｚｚｙ理想的性质，定义了Ｆｕｚｚｙ商代数，并证明了代数Ｙ关于代数Ｚ的同态ｆ－１［Ｏｚ］的Ｆｕｚｚｙ商代数与代数Ｚ同构等性质。     

偶氮苯液晶薄膜相位共轭的光学记录研究

利用间并四波混频研究了一种偶氮苯液昌聚合物的相位共轭和光学记录特性，在近共振条件下，用低功率Ｎｄ：ＹＡＧ倍频激光得到高效率的相位共轭光和高阶衍射光，当光强达到１０Ｗ／ｃｍ＾２量级时，薄膜显示出光记录效应，即在撒掉写入光之后，相位共轭波并不消失，进一步大光强到１０＾３Ｗ／ｃｍ＾２量级时，出现三组分别只与前向泵浦光，后向泵浦光和信号有关的高阶衍射光。其中观察到第三阶衍射光，且在撒掉任两束光后，所剩一束     

由自锁模钛宝石激光器产生19fs脉冲

由自锁模钛宝石激光器产生１９ｆｓ脉冲林位株，赖天树，陈毓川，郑向阳，徐杏绍，莫党（中山大学物理系，广州５１０２７５）自锁模钛宝石激光器是９０年代发展起来的新型固体可调谐激光器，它以其激光频谱调谐范围宽、能够产生飞秒级短脉冲、输出功率高、装置简单和工作...