Neuronal growth inhibitory factor inhibits pheochromocytoma PC12 in vitro

Neuronal growth inhibitory factor (GIF), named Metallothioneins-Ⅲ (MT-Ⅲ), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochromocytoma PC12 by the MTT (Thiazolyl blue) reduction assay. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for detecting neuronal growth inhibitory activity of GIF. Recombinant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhibiting PC12 may be that PC12 have some properties of cholinergic neuron. It must play an important role in discovering the mechanism of GIF’s neuronal growth inhibitory activity.     

Lyapunov exponents for synchronous 12-lead ECG signals

The Lyapunov exponents of synchronous 12-lead ECG signals have been investigated for the first time using a multi-sensor (electrode) technique. The results show that the Lyapunov exponents computed from different locations on the body surface are not the same, but have a distribution characteristic for the ECG signals recorded from coronary artery disease (CAD) patients with sinus rhythms and for signals from healthy older people. The maximum Lyapunov exponent L1 of all signals is positive. While all the others are negative, so the ECG signal has chaotic characteristics. With the same leads, L1 of CAD patients is less than that of healthy people, so the CAD patients and healthy people can be classified by L1, L1 therefore has potential values in the diagnosis of heart disease.     

12-Hydroxy-E-γ-bisabolene,a new sesquiterpene alcohol from a Caribbean sea whip of the genusPseudopterogorgia (Gorgonacea,Cnidaria)

Summary A new sesquiterpene alcohol, 12-hydroxy-E--bisabolene, is reported from an undescribed Caribbean sea whip of the genusPseudopterogorgia. The structure of this new alcohol was established based upon spectral analyses and through chemical interconversions.Acknowledgment. This research was supported by NOAA, Office of Sea Grant, Department of Commerce, under grant NA80AA-D-00120, and in part by the California State Resources Agency, project R/MP-22. The U.S. Government is authorized to reproduce and distribute reprints. We wish to acknowledge the mass spectral support provided by the Bioorganic Biomedical Mass Spectrometry Resource Center, University of California, San Francisco (A.L. Burlingame, Director) which is supported through NIH grant RR00719.     

Na5YSi4O12的合成方法比较及其离子导电性质研究

应用交流阻抗谱技术，测定了对用不同方法合成的钠快离子导体Na5YSi4O12纯相的离子电导和离子活化能．用扫描电子显微镜对样品烧结体表面进行了观察，对用溶胶——凝胶法和传统的固相反应法合成的Na5YSi4O12快离子导体与用微波法合成的导体相比，后者具有较好的界面效应和特异的聚集态、缺陷和微结构，从而导致离子导电电活化能下降．     

In-situ Mg77Cu12Zn5Y6 bulk metallic glass matrix composite with extraordinary plasticity

Mg base BMG alloys have attracted a great deal of attention for its low density and relative low cost. To date, BMG alloys with millimeter scale have been fab- ricated by using conventional copper cast and die cast method in Mg-Ni-Ce[1], Mg-Ni-La[2], Mg-C…     

USB接口的现场总线硬件研究

随着现场总线技术和计算机与外设接口技术的发展，建立现场总线网络节点和监控计算机之间可靠的通讯连接更加重要。本文提出了一种使用USB接口实现CAN总线网络与计算机连接的方案，并结合设计实例，论述了系统硬件构成和固件的设计方法。     

密度泛函研究Pb_(12)团簇的结构和电子性质

用密度泛函理论研究了Pb12团簇几种异构体的原子结构和电子性质,发现基态是形变二十面体笼结构,而完好的高对称性(Ih)二十面体结构是能量非常接近基态的亚稳态.高对称性团簇形成稀疏离散的电子态密度和大的电子能隙.     

活性炭固载杂多酸催化合成乙酸松油酯

以针剂碳为载体负载磷钨酸,催化合成乙酸松油酯。通过XRD晶相分析、N2吸附和酸性表征(NH3-TPD)对催化剂进行表征。分析磷钨酸/针剂碳催化合成乙酸松油酯的催化性能,讨论合成α-乙酸松油酯的适宜工艺条件。结果表明:该固载杂多酸催化合成乙酸松油酯,具有催化活性高、生产工艺简单、催化剂容易回收并可多次重复使用等优点。     

磷钨酸掺杂聚苯胺催化合成丁醛1,2-丙二醇缩醛

以磷钨酸掺杂聚苯胺H3PW12O40/Pan为催化剂,对以丁醛和1,2-丙二醇为原料合成丁醛1,2-丙二醇缩醛的反应条件进行了研究.实验表明:磷钨酸掺杂聚苯胺催化剂H3PW12O40/Pan是合成丁醛1,2-丙二醇缩醛的良好催化剂,较系统地研究了醛醇摩尔比、催化剂用量、反应时间诸因素对收率的影响.最佳反应条件为:n(丁醛):n(1,2-丙二醇) =1:1.2,催化剂用量为反应物料总质量的0.5%,环己烷为带水剂,反应时间50 min.上述条件下,丁醛1,2-丙二醇缩醛的收率可达87.9%.