Effects of rhubarb extracts on hyperexcitability of hippocampal CA1 neurons after fluid percussion injury

Objective To investigate the effects of rhubarb extracts, i.e. rhein and emodin, on the neuronal hyperexcitability and synaptic transmission, and to ,further reveal the mechanism of the secondary brain damage. Methods The fluid percussion injury （FPI） rat model and extracellular recording method were used. The evoked field potentials by stimulating Schaffer collaterals were collected from the ipsilateral （impact side） and the contralateral hippocampal CA1 areas of rat in vitro . And the field potentials, including the field excitatory postsynaptic potential and the population spike, were analyzed. Results After the impact was performed on the rat parietal cortex, the evoked field potentials in the ipsilateral hippocampus CA1 area were enhanced obviously. Rhubarb extracts reduced the slope of the field excitatory postsynaptic potential and the number of the population spike significantly while rhein and emodin increased the latency of the population spike obviously. Conclusion Rhubarb extracts, i.e. rhein and emodin, can depress the neuronal hyperexcitability, which suggests that rhein and emodin play an important role in protecting the central nervous system from neuronal damage after traumatic brain injury. FPI produces hyperexcitability of hippocampal CA1 neurons, probably by enhancing excitatory synaptic transmission.     

NONINVASIVE DETECTION OF BRAIN ACTIVITY VARIATION UNDER DIFFERENT DEPTH OF ANESTHESIA BY EEG COMPLEXITY

Objective To detect the change of brain activity under different depth of anesthesia （DOA） noninvasively. A,fethods The Lempel-Ziv complexity C（n） was used to analyze EEG and its four components （delta, theta, alpha, beta）, which was recorded from SD rats under different DOA. The relationship between C（n） and DOA was studied. Results The C（n） of EEG will decrease while the depth of anesthesia increasing and vice versa. It can be used to detect the change of DOA sensitively. Compared with power spectrum, the change of C（n） is opposite to that of power spectrum. Only the C （n） of delta rhythm has obvious variations induced by the change of DOA, and the variations of delta is as similar as the EEG＇s. Conclusion The study shows that the desynchronized EEG is replaced by the synchronized EEG when rat goes into anesthesia state from awake, that is just the reason why complexity and power spectrum appear corresponding changes under different DOA. C（n） of delta rhythm dynamic change leads to the change of EEG, and the delta rhythm is the dominant rhythm during anesthesia for rats.     

单节护壁掘进深度对护壁工作机理的影响研究

STS管幕结合洞桩法在国内首次被用于沈阳地铁奥体中心站.采用有限差分软件建立三维数值模型,重点研究了人工挖孔桩每节不同掘进深度对桩外围的变形、弯矩和剪力的影响.研究结果表明:随着每节掘进深度的增加,单节土体的最大变形量也随之增大,单节挖孔最大位移值出现在每节的3/4处;在0~5m的开挖深度范围内,掘进距离的改变对剪力变化值影响不大;随着开挖深度的增大,护壁所受剪力逐渐增大,剪力最大值出现在开挖6~8m范围内,剪力值达到17~18kN.     

FULLY AUTOMATIC FRAMEWORK FOR SEGMENTATION OF BRAIN MRI IMAGE

Automaticbraintissuesegmentationfrommag neticresonanceimages(MRI)isofgreatimportance forresearchandclinicalstudyofmuchneurological pathology.Duringthepastdecade,theMRIhashad agreatimpactonthediagnosticimagingofmosthu manorgansystem.Thesegmentationofbrai…     

基于立体视觉技术的磨粒显微测量方法

铁谱分析在航空发动机运行状态监控和故障诊断中有着极其重要的实际应用价值，准确获取铁谱磨粒的几何参数是进行有效分析的关键。但到目前为止，铁语磨粒的三维尺寸特别是厚度的测量仍然没有一套经济有效的方法，据此对基于立体视觉的磨粒显微测量方法做了长期的研究，并提出相应的软硬件系统和实现方法，初步解决了磨粒的三维测量问题。该方法根据双目立体视觉的深度感知机理，利用光学显微镜模拟体视模式进行光学成像，并辅助相应的匹配方法和计算方法来处理像对，获取微粒的厚度尺寸，并根据高度分布重建磨粒的表面形态。该方法达到了较好的实验效果，数据和模型结果均实现预期目标。     

RESEARCH OF GENETIC POLYMORPHISM OF 5-HTT IN CHILDHOOD AUTISM

Objective To reveal the relationship between the 5-HTTLPR and the Chinese Han nationality children with CA, compared the distribution of the 5-HTTLPR between the Han Chinese children with CA and healthy Han Chinese children , and analyzed the association between the 5-HTTLPR and clinical symptoms of the Han Chinese children with CA. Methods Genomic DNAs of fifty subjects including 25 autistic children and 25 controls were extracted from blood samples. PCR amplification using Oligonucleotide primers flanking 5-HTTLPR was performed. Results① Three kinds of alleles including the S （short） allele, the L （long） allele and the VL allele were found , and the 5-HTTLPR genotypes shown were S/S, L/L, S/L and L/VL. ②Allele frequencies did not differ significantly in patient groups in comparison with the control sample. No significant difference was identified between the observed 5-HTTLPR genotype distribution of the patient groups and control group. ③The distribution of homozygons and heterozygous subjects between the two groups differed significantly. ④ The genotypes of the 5-HTTLPR polymorphism correlated significantly with the Body Movement Factor. ⑤ The allele frequency of healthy Han Chinese population and that of healthy Japanese population were similar. The frequency of S allele in not only autistic subjects but also healthy children in this study was considerably more than that in Caucasians and the frequency of L allele in our subjects decreased correspondingly. Conclusion ① A significant difference in the allele frequency between the Han Chinese and Caucasian populations was found. ② The genotypes of the 5-HTTLPR polymorphism correlated significantly with the Body Movement Factor of the patients. ③ The homozygote and the L allele were positively relevant to CA and they might be the risk factors of CA. The heterozygote and the S allele were negatively relevant to CA and they might be the protective factors of CA.     

限制水域船舶纵向下水的动力学分析

为了对限制水域内船舶纵向下水运动进行完整而准确的预报,考虑兴波阻力、粘性阻力、锚链力、钢缆力、水流力、横向侧推力的动力效应以及不对称水域等因素对下水运动的影响,针对下水各阶段建立了船体运动模型,提出了一种较为完善的限制水域内下水运动理论计算方法.采用该方法对一艘45000吨化学品/成品油轮的下水运动进行了预报,并与实船下水测试结果进行了比较分析.结果表明,此方法可以较好地模拟船舶下水运动,为分析和判断船舶下水的安全性提供了依据.