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The Effects of electromagnetic pulse on the Protein Levels of Tight Junction Associated-Proteins in the Cerebral Cortex,Hippocampus,Heart,Lung,and Testis of Rats

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Biomedical and Environmental Sciences 2011年第4期24卷 438-444页

作者： QIU LianBo CHEN Chen DING GuiRong ZHOU Yan ZHANG MengYao Department of Blood Transfusion Xijing HospitalFourth Military Medical UniversityXi'an 710032ShannxiChina Department of Radiation Medicine Faculty of Preventive MedicineFourth Military Medical UniversityXi'an 710032ShannxiChina Department of Chemistry School of PharmacyFourth Military Medical UniversityXi'an 710032ShannxiChina

Objective To investigate changes in the expression of tight junction （TJ） proteins in the cerebral cortex,hippocampus,heart,lung,and testes of rats after exposure to electromagnetic pulse （EMP）.Methods Eighteen adult male Sprague-Dawley rats were divided into sham and exposure groups.The exposure groups received EMP at 200 kV/m for 200 pulses with a repetition rate of 1 Hz.The expression of TJ proteins （ZO-1,occludin,actin） in the several organs was examined by western blotting.Results ZO-1 levels in the cerebral cortex decreased 1 h and 3 h after EMP exposure compared with sham group （P0.05）.No significant difference was observed for occludin and actin.ZO-1 levels in the hippocampus increased 1 h and 3 h post-exposure （P0.05）,and occludin decreased after 3 h （P0.05）;however,actin was unaffected.ZO-1 levels in the heart increased 3 h post-exposure （P0.05）,occludin decreased 3 h post-exposure （P0.05）,and actin increased 1 h and 3 h post-exposure （P0.05）.ZO-1,occludin and actin levels in the lung decreased compared with those in the sham group （P0.05）.ZO-1 and occludin levels in the testes decreased 1 h and 3 h post-exposure （P0.05）,but actin showed no significant change.Conclusion Exposure to EMP altered the expression levels of TJ proteins,particularly ZO-1,in the organs of adult male rats,which may induce changes in barrier structure and function.

关键词： electromagnetic pulse Tight junction ZO-1 Occludin Actin

Detrimental Effect of electromagnetic pulse Exposure on Permeability of In Vitro Blood-brain-barrier Model

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Biomedical and Environmental Sciences 2013年第2期26卷 128-137页

作者： ZHOU Jia Xing DING Gui Rong ZHANG Jie ZHOU Yong Chun ZHANG Yan Jun GUO Guo Zhen Department of Radiation Medicine Preventive Medicine CollegeFourth Military Medical University

Objective To study the effect of electromagnetic pulse （EMP） exposure on permeability of in vitro blood-brain-barrier （BBB） model. Methods An in vitro BBB model, established by co-culturing brain microvascular endothelial cells （BMVEC） and astroglial cells （AC） isolated from rat brain, was exposed to EMP at 100 kV/m and 400 kV/m, respectively. Permeability of the model was assayed by measuring the transendothelial electrical resistance （TEER） and the horseradish peroxidase （HRP） transmission at different time points. Levels of BBB tight junction-related proteins were measured at O, 1, 2, 4, 8, 12, 16, 20, 24 h after EMP exposure by Western blotting. Results The TEER level was lower in BBB model group than in control group at 12 h after EMP, exposure which returned to its normal level at 24 h. The 24 h recovery process was triphasic and biphasic respectively after EMP exposure at 100 kV/m and 400 kV/m. Following exposure to 400 kV/m EMP, the HRP permeability increased at 1-12 h and returned to its normal level at 24 h. Western blotting showed that the claudin-5 and ZO-1 protein levels were changed after EMP exposure. Conclusion EMP exposure at 100 kV/m and 400 kV/m can increase the permeability of in vitro BBB model and BBB tight junction-related proteins such as ZO-1 and claudin-5 may change EMP-induced BBB permeability.

关键词： electromagnetic pulse Blood-brain-barrier Permeability TEER HRP ZO-1 Claudin-5

Effects of electromagnetic pulse on Bone Metabolism of Mice in vivo

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Biomedical and Environmental Sciences 2009年第6期22卷 518-521页

作者： KANG-CHU LI SHI-RONG MA GUI-RONG DING YAO GUO GuO-ZHEN GUO Department of Radiation Medicine Fourth Military Medical University Xi 'an 710032 Shaanxi China Department of Pathology Fourth Military Medical University Xi'an 710032 Shaanxi China

Objective To study the effects of electromagnetic pulse （EMP） on bone metabolism of mice in vivo. Methods Twenty-four male BALB/c mice were divided into a control group and 2 experimental groups （n=8）. The whole-body of mice in experimental groups were exposed to 50 kV/m and 400kV/m EMP, 400 pulses daily for 7 consecutive days at 2 seconds intervals. Alkaline phosphotase （ALP） activity, serum calcium concentration and osteocalcin level and trabecular bone volume （BV/TV, %） were measured immediately after EMP exposure by biochemical, ELISA and morphological methods. Results The ALP activity, serum calcium concentration and osteocalcin level and BV/TV in experimental groups remained unchanged after EMP exposure. Conelusion Under our experimental conditions, EMP exposure cannot affect bone metabolism of mice in vivo.

关键词： electromagnetic pulse Alkaline phosphotase Serum calcium Osteocalcin Trabecular bone volume

Influence of the external component on the damage of the bipolar transistor induced by the electromagnetic pulse

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Journal of Semiconductors 2010年第7期31卷 49-52页

作者：席晓文柴常春任兴荣杨银堂马振洋王婧 Key Laboratory of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices School of MicroelectronicsXidian University

A study on the influence of the external resistor and the external voltage source during the injection of the electromagnetic pulse（EMP） into the bipolar transistor（BJT） is carried out.Research shows that the increase of the external resistor R_b at base makes the burnout time of the device decrease slightly,the increase of the external voltage source V_（be） at base can aid the damage of the device when the magnitude of the injecting voltage is relatively low and has little influence when the magnitude is sufficiently high causing the device appearing the PIN structure damage,and the increase of the external resistor R_e can remarkably reduce the voltage drops added to the device and improve the durability of the device.In the final analysis,the effect of the external circuit component on the BJT damage is the influence on the condition which makes the device appear current-mode second breakdown.

关键词： electromagnetic pulse bipolar transistor current-mode second breakdown external component

Effect of electromagnetic pulse Exposure on Brain Micro Vascular Permeability in Rats

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Biomedical and Environmental Sciences 2009年第3期22卷 265-268页

作者： GUI-RONG DING KANG-CHU LI XIAO-WU WANG YONG-CHUN ZHOU LIAN-BO QIU JUAN TAN SHENG-LONG XU AND GUO-ZHEN GUO Department of Radiation Medicine Faculty of Preventive MedicineFourth Military Medical UniversityXi’an 710032ShaanxiChina

Objective To observe the effect of electromagnetic pulse (EMP) exposure on cerebral micro vascular permeability in rats. Methods The whole-body of male Sprague-Dawley rats were exposed or sham exposed to 200 pulses or 400 pulses (1 Hz) of EMP at 200 kV/m. At 0.5, 1, 3, 6, and 12 h after EMP exposure, the permeability of cerebral micro vascular was detected by transmission electron microscopy and immunohistochemistry using lanthanum nitrate and endogenous albumin as vascular tracers, respectively. Results The lanthanum nitrate tracer was limited to the micro vascular lumen with no lanthanum nitrate or albumin tracer extravasation in control rat brain. After EMP exposure, the lanthanum nitrate ions reached the tight junction, basal lamina and pericapillary tissue. Similarly, the albumin immunopositive staining was identified in pericapillary tissue. The changes in brain micro vascular permeability were transient, the leakage of micro vascular vessels appeared at 1 h, and reached its peak at 3 h, and nearly recovered at 12 h, after EMP exposure. In addition, the leakage of micro vascular was more obvious after exposure of EMP at 400 pulses than after exposure of EMP at 200 pulses. Conclusion Exposure to 200 and 400 pulses (1 Hz) of EMP at 200 kV/m can increase cerebral micro vascular permeability in rats, which is recoverable.

关键词： electromagnetic pulse Permeability Cerebral micro vascular Rats

Analysis of the damage threshold of the GaAs pseudomorphic high electron mobility transistor induced by the electromagnetic pulse

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Chinese Physics B 2016年第8期25卷 458-462页

作者：席晓文柴常春刘阳杨银堂樊庆扬史春蕾 Key Laboratory of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University

An electromagnetic pulse（EMP）-induced damage model based on the internal damage mechanism of the Ga As pseudomorphic high electron mobility transistor（PHEMT） is established in this paper. With this model, the relationships among the damage power, damage energy, pulse width and signal amplitude are investigated. Simulation results show that the pulse width index from the damage power formula obtained here is higher than that from the empirical formula due to the hotspot transferring in the damage process of the device. It is observed that the damage energy is not a constant, which decreases with the signal amplitude increasing, and then changes little when the signal amplitude reaches up to a certain level.

关键词： PHEMT electromagnetic pulse damage threshold empirical formula

electromagnetic pulse Protection Technique and Safety Management of Electric Power System

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Electromagnetic Pulse Protection Technique and Safety Manage...

Spatial and temporal evolution of electromagnetic pulses generated at Shenguang-Ⅱseries laser facilities

2004安全科学与技术国际会议

作者： CHENG Zhongqing1 2 WANG Yanwen1 JIANG Haibo2 & LIU Kejian1 (1 Graduate Student College China University of Mining and Technology Beijing 100083 China) (2 Navy Energy Conservation Technology Research Center Naval University of Engineering Tianjin 300450 China)

electromagnetic pulse (EMP) is generated by natural or man-made source. EMP can disturb and destroy the electronic and electrical system. It is necessary to electromagnetically harden and to improve e

关键词： electromagnetic pulse protection safety management electric power system

来源： cnki会议评论

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Plasma Science and Technology 2021年第11期23卷 35-41页

作者：何强友康宁任磊田超王传珂张智猛刘东晓杨雷刘会亚孙明营朱宝强周维民李廷帅 School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731People's Republic of China National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800People's Republic of China Laser fusion research center Chinese Academy of Engineering PhysicsMianyang 621900People's Republic of China

The distribution and sources of EMPs produced at Shenguang-Ⅱ(SG-Ⅱ)series laser facilities are systematically investigated.The results indicate that the EMP amplitudes in the SG-Ⅱps PW laser are very strong,one order higher than those from the SG-Ⅱlaser facility.EMPs outside the target chamber decrease exponentially with the distance from the measuring points to the target chamber center at the two laser facilities.Moreover,EMPs can be remarkably reduced when the picosecond laser together with the nanosecond laser is incident to targets compared to the SG-Ⅱps PW laser alone.The resulting conclusions are expected to offer experimental supports for further effective EMPs shielding design and achievement in high-power laser facilities.

关键词： laser electromagnetic pulse target intensity

Distortion Evaluation of EMP Sensors Using Associated-Hermite Functions

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Computers, Materials & Continua 2023年第1期74卷 1093-1105页

作者： Rupo Ma Siping Gao College of Command and Control Engineering Army Engineering UniversityNanjing210007China Department of Computer Information and Cyber Security Jiangsu Police InstituteNanjing210031China Department of Electrical and Computer Engineering National University of Singapore119260Singapore

electromagnetic pulse(EMP)is a kind of transient electromagnetic phenomenon with short rise time of the leading edge and wide spectrum,which usually disrupts communications and damages electronic equipment and system.It is challenging for an EMP sensor to measure a wideband electromagnetic pulse without distortion for the whole spectrum.Therefore,analyzing the distortion of EMP measurement is crucial to evaluating the sensor distortion characteristics and correcting the measurement results.Waveform fidelity is usually employed to evaluate the distortion of an antenna.However,this metric depends on specific signal waveforms,thus is unsuitable for evaluating and analyzing the distortion of EMP sensors.In this paper,an associated-hermite-function based distortion analysis method including system transfer matrices and distortion rates is proposed,which is general and independent from individual waveforms.The system transfer matrix and distortion rate can be straightforwardly calculated by the signal orthogonal transformation coefficients using associated-hermite functions.Distortion of a sensor vs.frequency is then visualized via the system transfer matrix,which is convenient in quantitative analysis of the distortion.Measurement of a current probe,a coaxial pulse voltage probe and a B-field sensor were performed,based on which the feasibility and effectiveness of the proposed distortion analysis method is successfully verified.

关键词： electromagnetic pulse associated-hermite functions system transfer matrix distortion rate