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EGB761改善缺血性脑卒中模型小鼠的认知功能障碍并降低小胶质细胞激活

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中国药理学通报 2024年第10期40卷 1872-1878页

作者：王华张驰张小广河南大学第一附属医院神经内科河南开封475000 河南科技大学基础医学与法医学院河南洛阳471000 河南大学第一附属医院神经外科河南开封475000

目的探讨EGB761对缺血性脑卒中后小鼠的认知功能障碍的改善作用及相关机制。方法将72只小鼠随机均分为4组(n=18):假手术组、模型组、低和高剂量EGB761治疗组。利用线栓法构建大脑中动脉闭塞/再灌注(MCAO/R)小鼠模型,其中低和高剂量EGB76... 详细信息

目的探讨EGB761对缺血性脑卒中后小鼠的认知功能障碍的改善作用及相关机制。方法将72只小鼠随机均分为4组(n=18):假手术组、模型组、低和高剂量EGB761治疗组。利用线栓法构建大脑中动脉闭塞/再灌注(MCAO/R)小鼠模型,其中低和高剂量EGB761组于MCAO/R术后分别给予50 mg·kg^(-1)和150 mg·kg^(-1)EGB761,每天1次,持续28天。TTC染色测量脑梗死体积;用改良神经功能评分(mNSS)表评估小鼠神经功能;水迷宫实验评估小鼠的学习认知功能;NeuN和TUNEL共染色检测神经元凋亡;Iba1免疫荧光染色评估小胶质细胞激活情况;Western blot检测TLR4、p-IKKɑ和NF-κB蛋白的表达水平。结果与模型组相比,低和高剂量EGB761组小鼠的脑梗死体积明显缩小(P<0.01),神经功能及学习认知功能明显改善(P<0.01),凋亡神经元百分比明显降低(P<0.01),小胶质细胞活化(P<0.01),TLR4、p-IKKɑ和NF-κB表达明显下降(P<0.05)。高剂量治疗组比低剂量治疗组疗效明显。结论EGB761可改善MACO/R小鼠的神经功能障碍和认知功能障碍,其机制可能与降低神经元凋亡,并可抑制TLR4/NF-κB通路减少小胶质细胞的过度激活有关。

关键词： EGB761 缺血性脑卒中小鼠认知功能障碍神经元小胶质细胞 TLR4/NF-κB通路

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不锈钢支架熔模铸造工艺优化

铸造 2024年第2期73卷 257-261页

作者：张晓光仓欣蕾彭彬辽宁工业大学机械工程与自动化学院辽宁锦州121001

通过ProCAST软件对除草机不锈钢支架进行熔模铸造的数值模拟,预测铸件缩孔缺陷分布情况,并对其浇注系统进行改善。利用正交试验对铸件的工艺参数进行研究,通过分析获得工艺参数的最佳方案。对该结果进行数值仿真以及实际铸造,发现铸件... 详细信息

通过ProCAST软件对除草机不锈钢支架进行熔模铸造的数值模拟,预测铸件缩孔缺陷分布情况,并对其浇注系统进行改善。利用正交试验对铸件的工艺参数进行研究,通过分析获得工艺参数的最佳方案。对该结果进行数值仿真以及实际铸造,发现铸件缺陷明显减少,这为不锈钢支架的生产提供了参考。

关键词：熔模铸造 ProCAST 不锈钢支架正交试验

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无人机灭火弹饰盖模流分析及注塑模具设计

塑料科技 2024年第4期52卷 121-126页

作者：张晓光程志超孟枭李顾学辽宁工业大学机械工程与自动化学院辽宁锦州121001

以无人机灭火弹的饰盖为研究对象,利用Moldflow软件从灭火弹饰盖的填充时间、流动前沿温度、熔接痕、气穴、翘曲变化五个方面对两种浇口设计方案进行对比分析,得到最优的浇口方案,并对两种冷却系统进行模流分析,得到较优的冷却系统。经... 详细信息

以无人机灭火弹的饰盖为研究对象,利用Moldflow软件从灭火弹饰盖的填充时间、流动前沿温度、熔接痕、气穴、翘曲变化五个方面对两种浇口设计方案进行对比分析,得到最优的浇口方案,并对两种冷却系统进行模流分析,得到较优的冷却系统。经锁模力的数值计算和模流分析,选择符合成型要求的注射机,然后运用正交试验优化工艺参数,从而降低饰盖的体积收缩率,通过对塑件总体温度分布和剪切速率与体积分布进行验证,最终得到优化后的注塑模具结构。结果表明:通过Moldflow软件分析和正交试验,可提高无人机灭火弹饰盖模具的设计效率和质量,且优化后的注塑模具结构合理,工作可靠,可以有效减少试模的成本,满足生产需求。实验为类似模具的设计提供了参考。

关键词：灭火弹饰盖模流分析正交试验注塑模具

A rare case of isolated non-compaction right ventricular myocardium

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Chinese Medical Journal 2009年第14期122卷 1718-1720页

作者： zhang xiao-juan ZHI guang HOU Hai-jun ZHOU xiao Cardiology Ward. Chinese PLA General Hospital. Beijing 100853 China

Isolated right ventricular noncompaction （IRNC） is a rare congenital cardiomyopathy resulting from an arrest in normal endomyocardial embryogenesis. The clinical syndrome includes systolic and diastolic dysfunction： some cases may have ventricular arrhythmias. We report a case of a female with the diagnosis of right ventricular non-compaction myocardium （RVNC） with normal left ventricular systolic function. To the best of our knowledge, there have been no reports of isolated ventricular non-compaction involving only the right ventricular before 2008. and there have only been described in very few cases of newborns and adult patients.

关键词： cardiomyopathies heart failure: echocardiography

积石山M_(S)6.2级地震诱发的黄土滑坡对山地光伏的影响研究

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价值工程 2024年第20期43卷 132-135页

作者：王海兵张效广甘肃省水利水电勘测设计研究院有限责任公司兰州730030

2023年12月18日23时59分,积石山县发生6.2级地震。研究区距震中约32km,本次地震对研究区影响烈度达Ⅵ度,引发了较多滑坡,对研究区内的山地光伏电站造成严重的经济损失。为此,本文对研究区地震诱发的滑坡发育机理进行了分析,为此类灾害... 详细信息

2023年12月18日23时59分,积石山县发生6.2级地震。研究区距震中约32km,本次地震对研究区影响烈度达Ⅵ度,引发了较多滑坡,对研究区内的山地光伏电站造成严重的经济损失。为此,本文对研究区地震诱发的滑坡发育机理进行了分析,为此类灾害风险预防提供了借鉴和参考。并在结论中得到了评估和减轻此类地质灾害风险的启示。

关键词：黄土滑坡积石山地震滑坡变形特征发育机理山地光伏

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Permeation of dimethyl sulfoxide into articular cartilage at subzero temperatures

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第3期13卷 213-220页

作者： Shao-zhi zhang xiao-yi YU guang-ming CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Osteochondral allografting has been proved to be a useful method to treat diseased or damaged areas of joint surfaces. Operational long-term stocks of grafts which supply a buffer between procurement and utilization would contribute to the commercialization or industrialization of this technology. Vitrification has been thought to be a promising method for successful preservation of articular cartilage （AC）, but high concentration cryoprotectants （CPAs） are used which may cause high cellular toxicity. An effective way to reduce CPA toxioity is to increase CPA concen- tration gradually while the temperature is lowered. Understanding the mechanism of （31~A permeation at subzero temperatures is important for designing the cryopreservation protocol. In this research, the permeation of dimethyl sulfoxide （MezSO） in ovine AC at subzero temperatures was studied experimentally. Pretreated AC discs were ex- posed in Me2SO solutions for different time （0, 5, 15, 30, 50, 80, and 120 min） at three temperature levels （-10, -20, and -30℃）. The Me2SO concentration within the tissue was determined by ultraviolet （UV） spectrophotometry. The diffusion coefficients were estimated to be 0.85×10-6, 0.48×10-8, and 0.27×10-6 cm2/s at -10, -20, and -,30℃, respectively, and the corresponding activation energy was 29.23 kJ/mol. Numerical simulation was performed to com- pare two Me2SO addition protocols, and the results demonstrated that the total loading duration could be effectively reduced with the knowledge of permeation kinetics.

关键词： Articular cartilage Vitrification Dimethyl sulfoxide Permeation Diffusion coefficient Subzero temperature

NUMERICAL SIMULATION OF 2D HORIZONTAL COOLING WATER DISCHARGE IN GENERALIZED CURVILINEAR COORDINATE

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Journal of Hydrodynamics 2006年第1期18卷 91-96页

作者： XIE Zuo-tao zhang xiao-feng TAN guang-ming YANG Fang-li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072 China

2D horizontal model is one of the major mathematical methods for the research on cooling water discharge from the power plant. In this paper, the shallow water equations are transformed under the generalized curvilinear coordinate system and the elliptic differential equations are used to generate curvilinear grids, so a model in generalized curviline ar coordinate is presented to simulate 2D horizontal cooling water, Governing equations of the model are discretized by finite volume method, and non-staggered grids and SIMPLE algorithm are introduced to simplify the program during the discretization. This model is used to simulate the movement of cooling water in a simplified meandering channel and a natural channel, calculating results indicate this model can correctly reflect the movement rules of cooling water, which verifies the model can be applied in engineering practice.

关键词： cooling water generalized curvilinear coordinate non-staggered grids numerical simulation SIMPLE algorithm

An Inverse Electromagnetic Scattering Method for One-Dimensional Inhomogeneous Media

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Chinese Physics Letters 2011年第1期28卷 82-85页

作者： LIN Zhi-Wei XU Xin zhang xiao-Juan FANG guang-You Key Laboratory for Electromagnetic Radiation and Detection Technology Institute of Electronics Chinese Academy of Sciences Beijing 100190

A frequency-domain inversion scheme for reconstructing the permittivity profile of one-dimensional inhomoge- neous media is proposed. The generalized reflection coefficients and the generalized transmission coefficients of the inhomogeneous media are used as the input data of the inverse model. A Newton-like iterative algorithm known as the generalized pulse-spectrum technique with the Tikhonov regularization is applied to solve the in- verse problem. Novel boundary conditions are proposed for the inverse problem and therefore the permittivity at the boundary of the inhomogeneous media is not required as prior knowledge. The choice of frequency points of the frequency-domain method is also investigated. Numerical examples are carried out to validate the inversion technique. Good agreements between the reconstructed profiles and the true profiles are shown.

关键词： Mathematical physics Accelerators beams and electromagnetism

Electromagnetic Scattering and Inverse Scattering of Layered Media with a Slightly Rough Surface

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Chinese Physics Letters 2011年第1期28卷 86-89页

作者： LIN Zhi-Wei XU Xin zhang xiao-Juan FANG guang-You Key Laboratory for Electromagnetic Radiation and Sen ~ing Technology Institute o1 Electronics Chinese Academy ot Sciences Beijing 100190

An electromagnetic （EA1） scattering model for layered media covered by a 3D infinite rough surface and the corresponding inversion technique are investigated. The work aims at remote sensing the surface roughness and dielectric constant for different depths of bear soil through radar measurement data. The forward problem is carried out by the wave decomposition method. The small perturbation method （SPM） and EM boundary conditions are employed to solve the integral equations introduced by the wave decomposition method. The second-order SPM solution of the scatteringfield is involved in the computation of the forward problem for the first time. The backseattering coefficients of multiple frequencies, multiple angles and multiple polarizations are employed to create a nonlinear optimization problem. A genetic algorithm is introduced to help the inversion procedure approaeh to the global minimum of the cost function. Examples are carried out to validate the inversion technique. The inverion results show good agreement with the forward problem with given parameters and pose good tolerance to the input data with the additive white Gaussian noise.

关键词： INVERSE scattering transform SURFACE roughness ELECTROMAGNETIC wave scattering LAYER structure (Solids) DIELECTRICS RANDOM noise theory