异丙酚对大鼠海马CAI区自发性兴奋性突触后电流的影响

目的:研究异丙酚对大鼠海马CA1区自发性兴奋性突触后电流(sEPSC)的影响。方法:断头法分离Wistar大鼠(13~19 d)海马半脑,用切片机切出400μm厚度的海马脑片,全细胞膜片钳记录CA1区锥体神经元sEPSC。20张脑片分为两组:脂肪乳剂组(n=10)和异丙酚组(n=10)。两组细胞稳定10~15 min后,加入90μl脂肪乳剂或异丙酚(相当于100μmol/L),记录40 min sEPSC。膜钳制电压为-70 mV。结果:100μmol/L异丙酚降低sEPSC的频率达68.1%,降低sEPSC的幅值达29.1%,缩短sEPSC的半衰期达49.3%;另外,异丙酚缩短sEPSC的上升时间达29.1%,减少曲线下面积达74.7%。结论:异丙酚通过影响突触前膜递质释放和突触后膜受体功能两个因素抑制兴奋性突触活动

鲢鱼放养控制北京城市河湖水华试验研究

介绍了利用鲢鱼控制北京城市河湖水华的试验研究,通过不同放养密度(0、17、51和103 g/m3)的现场围隔试验,对鲢鱼放养对水体水质和浮游生物的影响进行了分析。研究结果表明,鲢鱼放养使有鱼围隔中浮游生物量极低,从而使浮游植物基本不受浮游动物影响,而直接受鱼类影响;同时,中等密度(51 g/m3)的鲢鱼放养使水华蓝藻和微小藻的生长均得到了有效抑制,使藻类生物量最低。

抚仙湖外来黄颡鱼种群的年龄和生长特征

黄颡鱼(Pelteobagrusfulvidraco)是近年被无意引入到抚仙湖的外来鱼类,自2002年以来在渔获物中已形成了较为稳定的产量。根据2002年9月至2005年5月采集的708尾标本对抚仙湖黄颡鱼种群的年龄和生长特征进行了研究。以脊椎骨作为年龄鉴定的材料,表明种群的年龄分别为雌性0+-5+龄6个龄组和雄性0+-7+龄8个龄组组成;拟合的VonBertalanffy生长参数为雄性L∞=294·68mm,k=0·2476/y,t0=-0·0298y,W∞=209·93g;雌性L∞=257·13mm,

实验条件下生态修复过程中微型生物群落演替研究

在实验室恒流-修复微生态系统中,通过健康水体来对武汉东湖污染程度不同的水体进行持续替换,以模拟受不同程 度污染胁迫的自然水体恢复过程。其间定期测定微型生物群落的各种结构和功能参数,通过其变动机制和规律,再现修复过程中微 型生物群落的演替过程,并从生态学角度提出了东湖5个受到不同程度污染水体得到修复的换水率。

东湖紫外光敏感磷与可酶解磷的分布及其相互关系

初步讨论了武汉东湖不同工作站中紫外光敏感磷 (UVSP)与可酶解磷 (PHP)的季节变化以及间隙水中二者和碱性磷酸酶活性 (APA)的存在及其相互关系 间隙水中PHP与UVSP的存在 ,说明湖泊沉积物亦为间接有效的磷库 紫外光照射可显著提高间隙水中o P的浓度 ,却明显抑制溶解态碱性磷酸酶 (APase)的活性 ,这一结果未能支持UVSP释放o P的过程仍遵从酶促机制的假说 .

Determination of the surface area of common carp, Cyprinus carpio L.

A wrap method adaptation combined with AutoCAD2005 and Scion Image for Windows were used to determine the surface area of a fish. Compared with the corresponding r(2) and F of many models, the most accurate formula: S = 752.15W(0.675) (r(2) = 0.999, F = 18362.94, P < 0.0001) for estimating the surface area of common carp was obtained. Similarly, the fin formula: S = 1834.12W(0.708) (r(2) = 0.992, F = 2690.47, P < 0.0001) was also obtained for the same purpose. It was proven that these two formulae gave good estimates of surface and fin areas of four strains of common carp: Yellow-river carp, fancy carp, mirror carp and Xingguo red carp.

Fabrication and characterization of TO packaged high-speed laser modules - art. no. 682407

Various high-speed laser modules are fabricated by TO-Packaged processes, such as FP laser modules, DFB laser modules, and VCSEL modules. Furthermore,, the resonance among the circuit elements provides an approach to compensating the TO packaging parasitics, and improving the frequency response of the devices. The detailed equivalent circuit model is established to investigate both the laser diode and packaging comprehensively. The small-signal modulation bandwidths of the TO packaged FP laser, DFB laser and the VCSEL modules are more than 10, 9.7 and 8 GHz, respectively.

Evaluating the effect of dislocation on the photovoltaic performance of metamorphic tandem solar cells

The photovoltaic conversion efficiency for monolithic GaInP/GaInAs/Ge triple-junction cell with various bandgap combination (300 suns, AM1.5d) was theoretically calculated. An impressive improvement on conversion efficiency was observed for a bandgap combination of 1.708, 1.194, and 0.67 eV. A theoretical investigation was carried out on the effect of dislocation on the metamorphic structure's efficiency by regarding dislocation as minority-carrier recombination center. The results showed that only when dislocation density was less than 1.6x10(6) cm(-2), can this metamorphic combination exhibit its efficiency advantage over the fully-matched combination. In addition, we also briefly evaluated the lattice misfit dependence of the dislocation density for a group of metamorphic triple-junction system, and used it as guidance for the choice of the proper cell structure.

Light-excited structural instability of a-Si : H.

With the accumulation of experimental data, it has been recognized by many that the light-induced metastable change of a-Si:H, Staebler-Wronski effect (SWE), may be related to a structural instability of the whole a-Si:H network. However, direct evidence of such a structural change is still lacking. In the present paper, the efforts of our laboratory in this direction will be reviewed, including the light-induced changes of Si-H bond absorption, low frequency dielectric response, and an apparent photo-dilation effect.

基于UML和模型检测的安全模型验证方法

安全策略的形式化分析与验证随着安全操作系统研究的不断深入已成为当前的研究热点之一.文中在总结前人工作的基础上,首次提出一种基于UML和模型检测器的安全模型验证方法.该方法采用UML将安全策略模型描述为状态机图和类图,然后利用转换工具将UML图转化为模型检测器的输入语言,最后由模型检测器来验证安全模型对于安全需求的满足性.作者使用该方法验证了DBLP和SLCF模型对机密性原则的违反.