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Diffusion tensor imaging of the hippocampus reflects the severity of hippocampal injury induced by global cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2022年第4期17卷 838-844页

作者： Wen-Zhu Wang Xu liu zheng-Yi Yang Yi-zheng Wang hai-Tao Lu China Rehabilitation Science Institute School of Rehabilitation MedicineCapital Medical UniversityBeijing Bo’ai HospitalChina Rehabilitation Research CenterBeijingChina Beijing Key Laboratory of Neural Injury and Rehabilitation BeijingChina Department of Rehabilitation Medicine Beijing Friendship HospitalCapital Medical UniversityBeijingChina Brainnetome Center Institute of AutomationChinese Academy of SciencesBeijingChina

At present,predicting the severity of brain injury caused by global cerebral ischemia/reperfusion injury(GCI/RI)is a clinical *** such an injury,clinical indicators that can directly reflect neurological dysfunction are *** change in hippocampal microstructure is the key to memory formation and *** tensor imaging is a highly sensitive tool for visualizing injury to hippocampal *** hippocampal microstructure,brain-derived neurotrophic factor(BDNF),and tropomyosin-related kinase B(Trk B)levels are closely related to nerve injury and the repair process after GCI/RI,whether these indicators can reflect the severity of such hippocampal injury remains *** address this issue,we established rat models of GCI/RI using the four-vessel occlusion *** tensor imaging parameters,BDNF,and Trk B levels were correlated with modified neurological severity *** results revealed that after GCI/RI,while neurological function was not related to BDNF and Trk B levels,it was related to hippocampal fractional *** findings suggest that hippocampal fractional anisotropy can reflect the severity of hippocampal injury after global GCI/*** study was approved by the Institutional Animal Care and Use Committee of Capital Medical University,China(approval ***-2015-139)on November 9,2015.

关键词： brain-derived neurotrophic factor diffusion tensor imaging fractional anisotropy value global cerebral ischemia/reperfusion injury hippocampus Trk B

On the Downshift of Wave Frequency for Bragg Resonance

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China Ocean Engineering 2022年第1期36卷 76-85页

作者： PENG Ji TAO Ai-feng FAN Jun zheng Jin-hai liu Yu-ming Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China Quality Supervision Department China Renewable Energy Engineering InstituteBeijing 100120China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridge 02139USA

For surface gravity waves propagating over a horizontal bottom that consists of a patch of sinusoidal ripples,strong wave reflection occurs under the Bragg resonance *** critical wave frequency,at which the peak reflection coefficient is obtained,has been observed in both physical experiments and direct numerical simulations to be downshifted from the well-known theoretical *** has long been speculated that the downshift may be attributed to higher-order rippled bottom and free-surface boundary effects,but the intrinsic mechanism remains *** a regular perturbation analysis,we derive the theoretical solution of frequency downshift due to third-order nonlinear effects of both bottom and free-surface *** is found that the bottom nonlinearity plays the dominant role in frequency downshift while the free-surface nonlinearity actually causes frequency *** frequency downshift/upshift has a quadratic dependence in the bottom/free-surface *** bottom leads to a larger frequency downshift relative to the monochromatic *** addition,direct numerical simulations based on the high-order spectral method are conducted to validate the present *** theoretical solution of frequency downshift compares well with the numerical simulations and available experimental data.

关键词： gravity surface wave Bragg resonance frequency downshift regular perturbation analysis

Optimized design of LED freeform lens for uniform circular illumination

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第12期13卷 929-936页

作者： Peng liu Reng-mao WU Zhen-rong zheng hai-feng LI Xu liu State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

An optimization method is proposed for designing an LED freeform lens which produces a uniform circular pattern with high energy *** method is composed of three main aspects:design of the initial guess,parameterization of the freeform surface,and construction of the merit *** initial guess is created by solving an ordinary differential equation *** approach of selecting optimization points is introduced for parameterization of the freeform *** merit function is constructed by use of the irradiance uniformity and the efficiency of the *** examples are given,and the results show that the irradiance distribution is well controlled with a maximum uniformity(the relative standard deviation of irradiance,RSD) of 0.0122 and a maximum efficiency of 93.88%.This optimization method can be generalized to design freeform lenses with different lighting patterns or without rotational symmetry.

关键词： Illumination design Lenses Light emitting diode(LED) Non-imaging optics

Study on superprism effect in the multilayer optical thin film stack

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光学精密工程 2005年第4期13卷 454-458页

作者： SUN Xue-zheng GU Pei-fu CHEN hai-xing JIN Bo LI hai-feng liu Xu State Key Laboratory of Modern Optical Instrumentations Zhejiang University Hangzhou 310027 China

Researches show that multilayer optical thin film stack can exhibit superprism effect due to their large abnormal dispersions. We investigated and simulated this effect numerically in a 1-D non-periodic film structure-Fabry-Perot filters (FPF), which possess drastic change in phase and large group delay around wavelength of peak transmittance, and fabricated this device to realize remarkable superprism effect. We tested experimentally with the maximum spatial separation shift up to 65 μm, and the experimental result is in good agreement with the theory. Compared with the traditional prism, the total thickness of our structure is only 3.3 μm, and our prism shows a stronger angular resolution of 1.8°/nm.

关键词：薄膜涂覆技术多层膜 FPF

Enhanced ignition behavior of reactive material projectiles impacting fuel-filled tank

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Defence Technology（防务技术） 2019年第4期15卷 533-540页

作者： Shu-bo liu Ying Yuan Yuan-feng zheng Chao Ge hai-fu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Reactive material projectiles can be an extremely efficient lethality enhancement technology that incorporates the defeat mechanisms of chemical energy and kinetic *** paper presents such a research on the enhanced ignition behavior of reactive material projectiles impacting a fuel-filled ***,the ignition process description of the fuel-filled tank impacted by inert metal and reactive material projectiles is ***,ballistic impact experiments are performed to investigate the ignition effects of the fuel-filled tank impacted by reactive material versus tungsten alloy projectiles with mass *** fuel tank used for the experiments is a cylindrical steel casing structure filled with aviation kerosene and sealed with aluminum cover plates on both ends using screw *** experimental results indicate that,compared with impacts from tungsten alloy projectiles,there is dramatically enhanced structural damage to the fuel-filled tank and an enhanced ignition effect caused by reactive material projectile ***,an analytical model is developed,by which the effects of the aluminum cover plate thickness on critical structural failure energy of the fuel-filled tank and the total energy of the reactive material projectile deposited into the fuel-filled tank are *** analysis shows a good agreement with the experiments.

关键词： Reactive materials Fuel-filled tank Chemical energy release Ignition mechanism

导梁法在刚构桥边跨现浇段施工中的应用与设计分析

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价值工程 2021年第16期40卷 167-168页

作者：文明建梁成立段永凤王鹏刘海证云南省建设投资控股集团有限公司市政总承包部昆明650500 云南省建筑工程设计院有限公司昆明650500

连续刚构桥墩高较高,边跨现浇段长度一般在6-8m,根据墩高情况,多采用托架法、复合支架法、甚至满堂支架法等进行浇筑施工。本文以元蔓高速蛮板2号大桥为背景,基于工程实际,通过对比分析,最终选用上下导梁作为主要受力主梁,配合纵横分配... 详细信息

连续刚构桥墩高较高,边跨现浇段长度一般在6-8m,根据墩高情况,多采用托架法、复合支架法、甚至满堂支架法等进行浇筑施工。本文以元蔓高速蛮板2号大桥为背景,基于工程实际,通过对比分析,最终选用上下导梁作为主要受力主梁,配合纵横分配梁行程的受力系统,采用有限元软件Midas Civil进行集体受力分析,最终表明受力系统可靠,并运用于现场施工,望对类似工程提供参考。

关键词：边跨现浇段上下导梁法有限元分析

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骨钙素减轻糖尿病大鼠血-视网膜屏障的损伤

现代生物医学进展 2011年第13期11卷 2416-2418页

作者：张全鹏周利红刘政海劳梅丽海南医学院解剖学教研室海南海口571101 中南大学基础医学院解剖学与神经生物学系湖南长沙410013 南华大学医学院解剖学系湖南衡阳421001

目的:研究骨钙素(Osteocalcin)对链脲佐菌素诱导的糖尿病大鼠血-视网膜屏障的影响。方法:取健康SD大鼠24只,随机分为正常对照组、糖尿病1月(DM1)组、糖尿病骨钙素干预(DM1+OCGY)组。尾静脉注射STZ建立DM模型,成模后DM1+OCGY组腹腔注射... 详细信息

目的:研究骨钙素(Osteocalcin)对链脲佐菌素诱导的糖尿病大鼠血-视网膜屏障的影响。方法:取健康SD大鼠24只,随机分为正常对照组、糖尿病1月(DM1)组、糖尿病骨钙素干预(DM1+OCGY)组。尾静脉注射STZ建立DM模型,成模后DM1+OCGY组腹腔注射骨钙素(2.57 ***-.1d-1),DM1组腹腔注射等量生理盐水,1个月后处死动物。用伊文思蓝方法检测大鼠血-视网膜屏障的改变。结果:造模1月后大鼠视网膜血管渗透性显著增加,共聚焦显微镜显示红色荧光斑点主要分布在视网膜血管周围,给予骨钙素后,红色荧光斑点明显减少,进一步定量显示1M糖尿病大鼠视网膜伊文思蓝含量为57.4±8.7μg.g-1,骨钙素能够改变这种变化,DM1+OCGY组伊文思蓝含量为26.1±3.8μg.g-1。结论:骨钙素能抑制糖尿病视网膜病的血管渗漏,对糖尿病引起的血-视网膜屏障破坏有保护作用。

关键词：骨钙素血-视网膜屏障伊文思蓝糖尿病视网膜病

Study on the Propagation and Focusing Mechanism of Long Waves over A Submerged Atoll

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China Ocean Engineering 2023年第2期37卷 204-217页

作者： FU Dan-juan liu Bi-jin zheng Jin-hai WANG Gang CHEN Bi-qin School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China hainan Institute Zhejiang UniversitySanya 572025China Key Laboratory of Coastal Disaster and Protection Ministry of EducationHohai UniversityNanjing 210098China Fujian Polytechnic of Information Technology Fuzhou 350003China

An analytical solution for long waves propagating over a submerged atoll is established. The atolls involved in this study are annular coral reefs with large lagoons in the middle, and the expression of the cross section is a trinomial function of the radial distance, i.e., h=ar(2s)-br~s+h_0, where s is the positive rational number. This analytical solution extends the theory by Wang et al.(2018) as s is no longer limited to s=2/m, where m is the positive integer. In addition, by adjusting the terrain parameters properly, the analytic solution can be degenerated to describe the wave propagation over topography with a hump or pit. According to the relationship between wave rays and wave energy, the distribution characteristics and formation mechanism of energy over the topography are expounded. When the lagoon is non-existent, all wave rays converge at the x-axis, which results in an abrupt amplification of the wave amplitude around the convergence point. When a lagoon is mounted on the top of the atoll, the rays are scattered due to the refraction of the lagoon, and only some rays converge at the symmetrical axis and the ridges on both sides,which results in the amplification of wave amplitudes in these areas.

关键词： long waves analytic solution wave scattering submerged atoll wave propagation

THREE-DIMENSIONAL NUMERICAL MODELLING OF SUBMERGED DIKE ALIGNMENT IN CURVED ESTUARINE CHANNEL

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Journal of Hydrodynamics 2005年第5期17卷 601-606页

作者： zheng Jin-hai liu Ying-qi YAN Yi-xin ZHU Yu-liang Research Institute of Coastal and Ocean Engineering Hohai University Nanjing 210098 China

Submerged dikes were frequently built in curved estuarine channels to improve navigational conditions. A three-dimensional numerical model of tidal motions was developed to simulate flows through the submerged dike alignment in curved estuarine reach of complex bathymetry on the basis of satisfactory calibrations. Through the analysis of the morphological characteristics of the curved channel of the Huangpu River mouth in the Yangtze River Delta, a submerged dike alignment project was examined. The effect of the navigation channel improvement project and its influence on the flow regimes, the navigational conditions, the flood control and the operating conditions of harbours within the adjacent water area were evaluated, and the technical feasibility of the navigation channel improvement scheme was demonstrated.

关键词： submerged dike alignment three-dimensional numerical model curved estuarine channel morphological analysis