稳态检测技术在公路路基结构中检测抗变形能力的应用

本文针对目前现场对路基进行抗变形检测技术的缺陷,提出了一种适用于现场的稳态检测技术,指出了评定路基抗变形能力的新指标,并在此基础上研究路基在抵抗变形方面的匹配关系并进行分析计算,对于指导路基设计和现场质量控制都具有现实意义。     

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.     

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.     

FULLY AUTOMATIC FRAMEWORK FOR SEGMENTATION OF BRAIN MRI IMAGE

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

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.     

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.