铁氧体多层结构电波吸收体的研究

用三种不同磁导率μｉ的铁氧体基复合电波吸收材料制成双层结构电波吸收体,在７～１２ＧＨｚ频段Ａ～ｆ曲线与单层基本相似,存在两个吸收峰,但第二峰移向高频,吸收量Ａ由２０ｄＢ增至３７ｄＢ;在吸收介质层与反射板之间以及在两个介质层之间涂以介电型介质膜,使第一吸收峰移向高频,吸收量分别增至２９ｄＢ和２７ｄＢ;对其作用机理进行探讨。     

Plectonema boryanum作为外源质粒受体的筛选及其原生质球的制备与再生

对三种丝状蓝藻株系（ＰｈｏｒｍｉｄｉｕｍＬｕｒｉｄｕｍ，Ｐｈｏｒｍｉｄｉｕｍｆａｖｅｏｌａｒｕｍ和Ｐｌｅｃｔｏｎｅｍａｂｏ－ｒｙａｍｕｍ）的研究结果表明：Ｐ，ｂｏｒｙａｎｕｍ因无明显限制性内切核酸酶活性可作为受体进一步研究，对其原生质球的释出和新细胞再生的最适条件分析表明：０．１％溶菌酶作用的最适时间为２ｈ温度为３５℃，ｐＨ为７．０～７．５（０．８ｍｏｌ／Ｌ的甘露醇为最适渗透稳定剂）。这些条件适合于在ＢＧ－１１液体中释放原生质球及固体培养基上新细胞的再生。     

Application and realization of hierarchical network planning based on Web

Making use of Microsoft Visual Studio. NET platform, hierarchical network planning is realized in working procedure time-optimization of the construction by TBM. and hierarchical network graph of the construction by TBM is drawn based on browser. Then the theory of system realization is discussed, six components of system that can be reused are explained emphatically. The realization of hierarchical network panning in Internet provides available guarantee for controlling rate of progress in large-scale or middle-sized projects.     

Effects of calcineurin on LTP of rats <Emphasis Type="Italic">in vivo</Emphasis>

Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus. Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic CN plays a role in the induction of LTP in the hippocampus of the rats.     

MDC1 is coupled to activated CHK2 in mammalian DNA damage response pathways

Forkhead-homology-associated (FHA) domains function as protein-protein modules that recognize phosphorylated serine/threonine motifs. Interactions between FHA domains and phosphorylated proteins are thought to have essential roles in the transduction of DNA damage signals; however, it is unclear how FHA-domain-containing proteins participate in mammalian DNA damage responses. Here we report that a FHA-domain-containing protein-mediator of DNA damage checkpoint protein 1 (MDC1; previously known as KIAA0170)--is involved in DNA damage responses. MDC1 localizes to sites of DNA breaks and associates with CHK2 after DNA damage. This association is mediated by the MDC1 FHA domain and the phosphorylated Thr 68 of CHK2. Furthermore, MDC1 is phosphorylated in an ATM/CHK2-dependent manner after DNA damage, suggesting that MDC1 may function in the ATM-CHK2 pathway. Consistent with this hypothesis, suppression of MDC1 expression results in defective S-phase checkpoint and reduced apoptosis in response to DNA damage, which can be restored by the expression of wild-type MDC1 but not MDC1 with a deleted FHA domain. Suppression of MDC1 expression results in decreased p53 stabilization in response to DNA damage. These results suggest that MDC1 is recruited through its FHA domain to the activated CHK2, and has a critical role in CHK2-mediated DNA damage responses.     

A CORBA-Based Multidatabase System——Panorama Project

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Involvement of nitric oxide in the signal transduction of salicylic acid regulating stomatal movement

The effects and the relationship between sali-cylic acid(SA)and nitric oxide(NO) on Vicia faba L.stomatal movement were studied.The results here showed that exogenous SA and NO induced stomatal closure,100μmol/L SA induced a rapid and striking NO increase in the cytosol of guard cells.This phenomenon was largely prevented by 2000μmol/L 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide(PTIO),a specific NO scavenger,and 25μmol/L N^G-nitro-L-Arg-methyl eater (L-NAME),an inhibitor of NO synthase(NOS) in mammalian cells that also inhibits plant NOS.In addition,SA-induced stomatal closure was largely prevented by PTIO and L-NAME.These results provide evidence that guard cells generate NO in response to SA via NOS-like activity,and that such NO production is required for full stomatal closure in response to SA.H-(1,2,4)-oxadiazole-[4,3-α]quinoxalin-l-one(ODQ),an inhibitor of guanylate cyclase,and nicotinamide,an antagonist of cADPR production,inhibited the effects of SA-and NO-induced stomatal closure.It suggests that both cGMP and cADPR might mediate the signal transduction of SA and NO-induced stomatal closure.     

多波长光谱法检测乙烯火焰中温度和碳黑生成

提出用光谱仪测量轴对称扩散火焰在800~950 nm波长范围的单色辐射强度,用阿贝尔逆变换从单色辐射强度中求解出源项H,再根据火焰复折射率函数与波长的关系,从源项H中同时计算出火焰温度和碳黑体积分数.光谱仪用黑体炉进行标定,对乙烯扩散火焰中部和上部的进行了检测,给出了火焰温度和碳黑体积份额沿半径的分布,检测结果与光学法相比具有较小误差,表明该方法是可行的.     

浅谈公路旧桥的加固

作者根据近年对超限运输桥梁及大中型桥梁的加固实践经验,介绍了公路旧桥各组成部分的加固方法和施工措施。     

生态观对区域发展规划的方法论研究

概括分析了生态足迹和区域发展规划的概念、理论及发展背景,并对其理论的国内外演变历程加以详细论述,尤其是对生态足迹模型理论做了深入的探析.在此基础上,通过分析生态观对经济发展产生的作用、生态观为区域规划带来的影响以及区域规划为生态经济的发展带来的条件,来完成生态观对区域发展规划的方法论研究,以期为制定区域经济及区域可持续发展政策提供理论支持.