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Effect and mechanism of on-chip electrostatic discharge protection circuit under fast rising time electromagnetic pulse
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作者 Mao Xinyi Chai Changchun +3 位作者 Li Fuxing Lin Haodong Zhao Tianlong Yang Yintang 《强激光与粒子束》 CAS CSCD 北大核心 2024年第10期44-52,共9页
The electrostatic discharge(ESD)protection circuit widely exists in the input and output ports of CMOS digital circuits,and fast rising time electromagnetic pulse(FREMP)coupled into the device not only interacts with ... The electrostatic discharge(ESD)protection circuit widely exists in the input and output ports of CMOS digital circuits,and fast rising time electromagnetic pulse(FREMP)coupled into the device not only interacts with the CMOS circuit,but also acts on the protection circuit.This paper establishes a model of on-chip CMOS electrostatic discharge protection circuit and selects square pulse as the FREMP signals.Based on multiple physical parameter models,it depicts the distribution of the lattice temperature,current density,and electric field intensity inside the device.At the same time,this paper explores the changes of the internal devices in the circuit under the injection of fast rising time electromagnetic pulse and describes the relationship between the damage amplitude threshold and the pulse width.The results show that the ESD protection circuit has potential damage risk,and the injection of FREMP leads to irreversible heat loss inside the circuit.In addition,pulse signals with different attributes will change the damage threshold of the circuit.These results provide an important reference for further evaluation of the influence of electromagnetic environment on the chip,which is helpful to carry out the reliability enhancement research of ESD protection circuit. 展开更多
关键词 fast rising time electromagnetic pulse damage effect electrostatic discharge protection circuit damage location prediction
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Effects of Slow Release Fertilizer on the Yield and Nutrient Use Efficiency of Carnation and Its Environmental Protection Effect 被引量:4
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作者 杜彩艳 段宗颜 +1 位作者 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第4期571-575,共5页
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyl... [Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture. 展开更多
关键词 Slow release fertilizer CARNATION YIELD Nutrient use efficiency Environmental protection effect
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Mechanical analysis of effective pressure relief protection range of upper protective seam mining 被引量:10
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作者 Yin Wei Miao Xiexing +1 位作者 Zhang Jixiong Zhong Sijian 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期537-543,共7页
This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the develo... This paper analyzes the control mechanism of coal and gas outbursts and proposes the concept of an effective pressure relief protection range, based on the stress relief of the underlying coal-rock mass and the development of a plastic zone. Also this study developed a stress change and fracture development model of the underlying coal-rock mass. In addition, the stress and depth of fracture of any point in the floor were deduced with the application of Maple Calculation Software. The specific engineering parameters of the Pingdingshan No. 12 colliery were applied to determine the relationship between the depth of fracture in the floor and the mining height. The pressure-relief principle of the underlying coal-rock mass was analyzed while varying the mining height of the upper protective seam. The findings indicate that as the depth of fracture in the floor increases, the underlying coal-rock mass experiences a limited amount of pressure relief, and the pressure relief protection range becomes narrower.Additionally, the stress distribution evolves from a ‘‘U" shape into a ‘‘V" shape. A 2.0 m mining height of protective seam situates the outburst-prone seam, Ji_(15), within the effective pressure relief protection range. The fracture development and stress-relief ratio rises to 88%, ensuring the pressure-relief effect as well as economic benefits. The measurement data show that: after mining the upper protective seam, the gas pressure of Ji_(15) dropped from 1.78 to 0.35 MPa, demonstrating agreement between the engineering application and the theoretical calculation. 展开更多
关键词 Upper protective seam Principle of pressure relief effective protection range Gas pressure
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Implementation Effect of Farmland Protection in Urumqi-Changji Economic Zone,China 被引量:2
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作者 LI Jiang-nan 《Asian Agricultural Research》 2010年第7期30-34,38,共6页
A multi-level evaluation index system is established with farmland protection as the target layer,farmland quantity,farmland quality andfarmland sustainable development as the criterion layer.And the index layer inclu... A multi-level evaluation index system is established with farmland protection as the target layer,farmland quantity,farmland quality andfarmland sustainable development as the criterion layer.And the index layer includes the quantity change of farmland,per capita farmland area,multiple cropping index,total grain yield,unit grain yield,per capita grain security coefficient,and unit machinery dynamical input.Both expert eval-uation method and factor analysis method are used to determine the weight of index.According to the data in farmland area,grain yield and eco-nomic development in Urumqi-Changji Economic Zone in the years 1996-2007,a comprehensive evaluation model of intensive farmland use inUrumqi-Changji Economic Zone is established after data standardization.The overall implementation effect of farmland protection policy is ana-lyzed by integrating the farmland quantity,farmland quality and sustainable development.Result shows that implementation effect of farmland pro-tection shows an upward trend in general in Urumqi-Changji Economic Zone in the years 1996-2007,with a fluctuation in the years 2000-2003and a stable rising phase from 2004 till now.The maximum value is 0.779 in the year 2007;the minimum value is 0.242 in the year 1996;and themean value in the years 1996-2007 is 0.454.Farmland protection at first strictly controls the farmland quantity,then pays attention to farmlandquality,and finally focuses on the sustainable use of farmland. 展开更多
关键词 Farmland protection Implementation effect Urumqi-Changji Economic Zone China
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Effectiveness Evaluation of the Construction of the Natural Forest Resources Protection Project in Haikou Forest Farm of Kunming
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作者 ZHANG Zhihong WANG Yating +1 位作者 CHEN Jinlong YAN Yi 《Journal of Landscape Research》 2018年第2期42-44,共3页
The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, fo... The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, forest pests, and money management was briefed. Achievements made in the implementation of natural forest protection project in Haikou Forest Farm were analyzed, and problems existing in the project as well as corresponding countermeasures were expounded. 展开更多
关键词 Haikou Forest Farm Natural forest protection project effectiveness evaluation SUGGESTION
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Effects of Lead on pH and Temperature-Dependent Substrate-Activation Kinetics of ATPase System and its Protection by Thiol Compounds in Rat Brain
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作者 B.RAJANNA C.S.CHETTY +1 位作者 T.C.STEWART S.RAJANNA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第4期441-451,共11页
Lead (Pb) inhibited the activities of Na+ -K+ ATPase (IC50= 2.0×10^(-6) M), K + -Para-Nitrophenyl phosphatase (PNPPase) (IC50= 3.5×10^(-6) M) and [3H]-ouabain binding (IC50 = 4.0×10^(-5) M) in rat brain... Lead (Pb) inhibited the activities of Na+ -K+ ATPase (IC50= 2.0×10^(-6) M), K + -Para-Nitrophenyl phosphatase (PNPPase) (IC50= 3.5×10^(-6) M) and [3H]-ouabain binding (IC50 = 4.0×10^(-5) M) in rat brain P2 fraction. A variable temperature or pH significantly elevated the inhibition of Na+-K+ ATPase by Pb in buffered acidic, neutral and alkaline pH ranges. Noncompetitive inhibition with respect to activation of Na+ -K+ ATPase by ATP was indicated by a variation in Vmax values with no significant changes in Km values at any temperature studied. In the presence of Pb, for Na+ -K+ ATPase at pH 6.5 and 8.5, Vmax was decreased with an increase in Km values suggesting a mixed type of inhibition. Sulfhydryl agents such as dithiothreitol (DTT) and cvsteine (Cyst), but not glutathione (GSH) offered varied levels of protection against Pb-inhibition of Na + -K+ ATPase at pH 7.5 and 8.5. The present data suggest that inhibition of Na+ -K+ ATPase by Pb is both temperature and pH-dependent. These results also indicate that Pb inhibited Na + -K + ATPase by interfering with phosphorylation of enzyme molecule and dephosphorylation of the enzyme-phosphoryl complex and exerted an effect similar to that of SH-blocking agents. 展开更多
关键词 effects of Lead on pH and Temperature-Dependent Substrate-Activation Kinetics of ATPase System and its protection by Thiol Compounds in Rat Brain ATPASE PH
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Study on Effective Measures of Environmental Protection for Sustainable Development of Tourism Industry in the World Natural Heritage Wulingyuan
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作者 YangMeixia ZhouGuohai 《Ecological Economy》 2005年第2期83-88,共6页
In the course of exploiting its tourist resources and developing tourism industry in the early days in Wulingyuan, the government did not pay enough attention and no forceful measures were taken to control the environ... In the course of exploiting its tourist resources and developing tourism industry in the early days in Wulingyuan, the government did not pay enough attention and no forceful measures were taken to control the environment. As a result, a series of problems are produced. By analyzing the relationship between the tourism development in Wulingyuan scenic area and its environmental evolution, the paper exposes the basic reason why these environmental problems are produced, and according to the requirement of developing tourism, the paper puts forward some effective measures to reasonably control the distribution of the tourists flow and to protect tourist resources as well as the environment, so as to achieve the sustainable development of the area. 展开更多
关键词 effective measures tourism sustainable development environmental protection Wulingyuan.
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Research on the Copyright Protection Technology of Digital Clothing Effect Diagram
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作者 Yongqiang Chen Lihua Peng 《国际计算机前沿大会会议论文集》 2017年第1期182-184,共3页
As a kind of digital clothing design works,digital clothing effect diagram shows fast and roughly designer intent expression and needs protection of digital copyright protection technology.A novel digital clothing eff... As a kind of digital clothing design works,digital clothing effect diagram shows fast and roughly designer intent expression and needs protection of digital copyright protection technology.A novel digital clothing effect diagram copyright protection scheme and some algorithms based on digital image watermark technology are proposed,used by two-dimensional chaotic encryption watermark generation algorithm to generate watermark data,watermark embedding algorithm twice using genetic algorithm to obtain the optimal embedding position and embedding strength,and watermark verification algorithm to determine the copyright ownership.Experimental results and analyses show that the proposed scheme and algorithms have the feasibility and effectiveness. 展开更多
关键词 CLOTHING effect DIAGRAM DIGITAL COPYRIGHT protection Image WATERMARK PHOTOSHOP
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The Effect of Evidence-based Management on Occupational Protection of Nurses Who Perform Chemotherapy
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作者 Liping Yang 《Journal of Clinical and Nursing Research》 2021年第4期8-11,共4页
Objective:The study was to explore the effect of evidence-based management in occupational protection for nurses who perform chemotherapy.Methods:40 chemotherapy nurses were selected,20 of them were included in the ex... Objective:The study was to explore the effect of evidence-based management in occupational protection for nurses who perform chemotherapy.Methods:40 chemotherapy nurses were selected,20 of them were included in the experimental group for evidence-based management,and the other 20 were included in the control group for routine management.Results:Compared with the control group,there were significantly fewer adverse nursing events in the experimental group,and P<0.05.Conclusion:The effect of evidence-based management in occupational protection of nurses who perform chemotherapy is significant. 展开更多
关键词 Evidence-based management Nurses who perform chemotherapy The effect of occupational protection
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Thermal features of Qinghai-Tibet Railway Embankment with Crushed-stone Slope Protection in Permafrost Regions
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作者 Guoyu Li,Ning Li,Wei Ma,Huijun Jin,Yu Sheng State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science,Lanzhou 730000,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期58-58,共1页
The Embankment with Crushed-Stone Slope Protection(ECSSP) in permafrost regions is an effective measure to cool subgrade and protect permafrost.It can mitigate the engineering hazards of the Qinghai-Tibet railway in t... The Embankment with Crushed-Stone Slope Protection(ECSSP) in permafrost regions is an effective measure to cool subgrade and protect permafrost.It can mitigate the engineering hazards of the Qinghai-Tibet railway in the permafrost regions. Considering the influence of the noctumal cold air during summer months in Qinghai-Tibet Plateau。 展开更多
关键词 Qinghai-Tibet railway EMBANKMENT with crushed-stone SLOPE protection mechanisms of cooling effect THERMAL REGIME heat flow
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AlO_x/LiF composite protection layer for Cr-doped(Bi,Sb)_2Te_3 quantum anomalous Hall films
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作者 欧云波 冯洋 +7 位作者 冯硝 郝镇齐 张立果 刘畅 王亚愚 何珂 马旭村 薛其坤 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期10-14,共5页
We have realized robust quantum anomalous Hall samples by protecting Cr-doped(Bi,Sb)2Te3 topological insulator films with a combination of LiF and A1Ox capping layers.The AlOx/LiF composite capping layer well keeps ... We have realized robust quantum anomalous Hall samples by protecting Cr-doped(Bi,Sb)2Te3 topological insulator films with a combination of LiF and A1Ox capping layers.The AlOx/LiF composite capping layer well keeps the quantum anomalous Hall states of Cr-doped(Bi,Sb)2Te3 films and effectively prevent them from degradation induced by ambient conditions.The progress is a key step towards the realization of the quantum phenomena in heterostructures and devices based on quantum anomalous Hall system. 展开更多
关键词 quantum anomalous Hall effect AlOx LiE protection layer
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Review of Groundwater Protection and Management in China
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作者 刘丹 张爱平 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期266-274,共9页
This review begins with an introduction of groundwater resources in China and their distribution characteristic,followed by an elaboration of the exploitation and utilization of groundwater and the negative environmen... This review begins with an introduction of groundwater resources in China and their distribution characteristic,followed by an elaboration of the exploitation and utilization of groundwater and the negative environmental effects from groundwater overexploitation, and a description of the existing groundwater protection and management measures. At last, the existing problems in groundwater protection and management, with some suggestions, are presented. 展开更多
关键词 GROUNDWATER Negative environmental effect UTILIZATION protection MANAGEMENT
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Tele-Protection Implementation Using IEEE 1588 Precision Time Protocol in Colombian High Power Substations 被引量:1
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作者 Hermes Eslava Luis Alejandro Rojas Danny Pineda 《Journal of Power and Energy Engineering》 2015年第4期23-28,共6页
Optical fiber has been used as typical physical transmission medium in Colombian high power substations for effective communication between substations and control centers. However, suita- ble transmissions of tele-pr... Optical fiber has been used as typical physical transmission medium in Colombian high power substations for effective communication between substations and control centers. However, suita- ble transmissions of tele-protection services continues to be a challenging area in the electrical- supply sector since link stability as well as various performance tests suggest that link recurrence requirements still exhibit limitations when using Metroethernet networks in this context. At pre- sent, improvements have been achieved via proprietary protocols such as Mirrored Bits, which matches the performance of a tele-protection link transmission under normal operation conditions. However, this imposes commercial limitations on the Colombian electrical-supply sector since proprietary protocols hinder fair competition among manufacturers. This is the rationale behind conducting trials with precision time protocol as it is defined in IEEE 1588 standard. The main purpose is to validate whether, under real operation conditions, it is possible to substitute such tele-protection links via Metroethernet networks, yet considering a standard protocol that allows incorporating various pieces of equipment from different manufacturers into the system as well as providing common benefits derived from using this type of communication networks. The present work provides technical results obtained after conducting various simulated tele-trigger tests, including stress tests, where results-stability validation occurs through network-saturation simulations. These saturation conditions are achieved by incorporating additional traffic, which involves several switching events over link paths and permits validating tele-protection-response timing when specifically using IEEE 1588 precision time protocol. Based on the aforementioned reasons as well as on the resulting benefits, a series of laboratory tests have been defined in order to evaluate delay and availability on tele-protection services when transported over IP networks. 展开更多
关键词 METRO ETHERNET IEEE 1588 IEC 61850 Tele-protection effective Communications Tele-Trigger Simulations
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Conclusions on the Implementation of Regulation of the National Significant Seismic Monitoring and Protection Regions from 1996 to 2012 in the Chinese Mainland
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作者 Chao Hongtai Gao Mengtan +7 位作者 Li Bo Chen Shijun Liang Kaili Ma Yuxiang Wang Feng Wu Guochun Lang Cong Wu Xinyan 《Earthquake Research in China》 CSCD 2015年第1期8-20,共13页
The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.T... The regulation of the National Significant Seismic Monitoring and Protection Regions(NSSMPR for short) is defined by the Law of the Peoples Republic of China on Protecting Against and Mitigating Earthquake Disasters.The first stage of implementation of the regulation of NSSMPR in the Chinese mainland was finished from 1996 to 2005.The second stage is being carried on from 2006 to 2020.With the support of the National Social Science Foundation,this paper follows up and evaluates the implementation of the regulation of NSSMPR from 1996 to 2012 in the Chinese mainland.Based on analysis of earthquake examples and investigation data,we find that the effect of disaster mitigation is good,and on this basis,some suggestions are proposed to improve the regulation of NSSMPR. 展开更多
关键词 The National Significant Seismic Monitoring and protection Regions Legalregulation effect and progress Measures on protecting against andmitigating earthquake disasters
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Protective effects of baffles with different positions,row spacings,heights on debris flow impact
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作者 SUN Xinpo CHEN Min +5 位作者 BI Yuzhang ZHENG Lu CHE Chi XU Ao TIAN Zijian JIANG Zheyuan 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2352-2367,共16页
The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural haza... The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural hazards such as landslides and mudslides.This study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow protection.Debris flow velocity and kinetic energy variations were studied through single-factor experiments.Suitable baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris flow.Subsequently,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of baffles.The research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their energy.When the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition area.Similarly,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition area.Through orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>h.When the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>h.The experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9. 展开更多
关键词 Debris flow BAFFLE Protective effect Discrete element
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Study on the effect of four kinds of raw materials in hypertonic dehydration cell model
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作者 Yuanyuan Gao Qidan Tan +3 位作者 Chencan Cao Haifeng Chen Yuying Jia Lei Liu 《日用化学工业(中英文)》 CAS 北大核心 2024年第10期1218-1226,共9页
It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The ... It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The safety mass concentrations of four raw materials were screened by detecting cell viability,and the secretion of hyaluronic acid(HA)was determined using the ELISA method.The expression of HaCaT barrier function related genes(OVOL1,EREG,TGM1,TGM2,IVL,IRF6,THBS1,CASP14)was detected at the mRNA level to explore the regulatory effect of four raw materials on these genes.The results demonstrate that pretreatment with the four kinds of raw materials could increase the cell viability after hyperosmotic dehydration,promote the secretion of HA,and improve the expression of barrier function related genes after hyperosmotic dehydration,among which panthenol and Calendula officinalis L.are better.The results show that the four raw materials have a certain protective effect on the hyperosmotic dehydration cell model,which provides data support for its application in cosmetics. 展开更多
关键词 hypertonic dehydration cell model protective effect barrier repair efficacy evaluation of cosmetics soothing ingredients
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Preliminary study on the protective effect of electroacupuncture Neiguan acupoint pretreatment on rats with myocardial ischemia-reperfusion injury:role of the miR-214-3p/NCX1 axis
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作者 Hai-Long Fan Ya-Qin Liu +4 位作者 Li-Li Jiang Qi-Rong Li Li-Li Niu Li-Zhen Yang Fu-Ran Du 《Integrative Medicine Discovery》 2024年第27期1-11,共11页
Background:Ischemia-reperfusion can worsen myocardial damage and increase the risk of death.Studies have revealed that ischemic preconditioning provides the best endogenous protection against myocardial ischemia-reper... Background:Ischemia-reperfusion can worsen myocardial damage and increase the risk of death.Studies have revealed that ischemic preconditioning provides the best endogenous protection against myocardial ischemia-reperfusion injury(MIRI),and the principle of electroacupuncture(EA)preconditioning is comparable to that of myocardial ischemic preconditioning adaption.Our earlier research demonstrated that EA pretreatment inhibits the expression of calmodulin-dependent protein kinase IIδ(CaMKIIδ),sodium/calcium exchanger 1(NCX1),and cyclophilin D,hence providing protection against MIRI.However,the exact mechanism is still unknown.The expression of NCX1 mRNA is directly regulated by microRNA-214(miR-214).Moreover,it suppresses the levels of CaMKIIδand cyclophilin D.Whether these variables contribute to EA preconditioning to improve MIRI needs to be investigated,though.This study aimed to preliminarily determine whether EA pretreatment ameliorates MIRI by modulating the miR-214-3p/NCX1 axis.Methods:We used a rat MIRI model to investigate the effect of EA pretreatment on MIRI and the expression of miR-214-3p.In addition,adenovirus injection inhibited miR-214-3p expression in the rat MIRI model,and the influence of EA pretreatment towards MIRI was observed in the context of blocked miR-214-3p expression.Both the myocardial histological abnormalities and the alterations in the ST segment of the rat electrocardiogram were analyzed.NCX1 mRNA,cyclophilin D,and CaMKIIδexpression levels were also analyzed.Results:EA pretreatment improved MIRI.In rats with MIRI,EA administration increased miR-214-3p expression while decreasing NCX1 mRNA,cyclophilin D,and CaMKIIδproteins in cardiac tissues.The beneficial effect of EA pretreatment against MIRI was reversed,coupled with elevated levels of NCX1 mRNA,cyclophilin D,and CaMKIIδprotein expression,when an adenovirus injection disrupted the expression of miR-214-3p.Conclusions:Our findings preliminarily show that EA pretreatment inhibits the expression of NCX1 mRNA,cyclophilin D,and CaMKIIδproteins via miR-214-3p,hence exerting MIRI protection. 展开更多
关键词 myocardial ischemia-reperfusion injury miR-214-3p NCX1 ELECTROACUPUNCTURE protective effect
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Acute Toxicity of Jinchuan Formula Plum Wine Extract and Its Protective Effect on Mice with Liver Injury
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作者 Hairong ZHONG Yun TENG +1 位作者 Limin LI Yuan LIU 《Medicinal Plant》 2024年第2期30-32,37,共4页
[Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal do... [Objectives]To investigate the acute toxicity and hepatoprotective effect of Jinchuan formula plum wine extract on mice,determine its safety range,and evaluate its hepatoprotective effect.[Methods]The median lethal dose(LD_(50))was determined by acute toxicity test with the toxic reaction and mortality of mice as indexes.Sixty Kunming mice were randomly divided into 6 groups:normal control group,model group(ConA-induced liver injury model),Jinchuan formula plum wine high,medium and low dose groups(1.0,0.5,0.25 g/kg)and silybin group(0.1 g/kg).The levels of ALT,AST,LDH in serum and TG,VLDL in liver were measured.After HE staining,the pathological changes of liver tissue in mice were observed,and the liver protective effect of Jinchuan formula plum wine extract was analyzed and evaluated.[Results]LD_(50)was 11.18 g/kg,and the 95%confidence limit of LD_(50)was 10.31-12.05 g/kg.The high-dose group of Jinchuan formula plum wine extract could significantly reduce the serum ALT and AST activities of ConA-induced liver injury mice(P<0.05).[Conclusions]Jinchuan formula plum wine extract is relatively safe,and also has a protective effect on liver injury. 展开更多
关键词 Jinchuan formula plum wine extract Acute toxicity test ConA-induced liver injury Liver protective effect
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Protective effect of Solanum Nigrum Linn green fruit ethanolic extract on alcoholic liver injury in mice
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作者 Xiaoli Wang Ning Wang +1 位作者 Nan Yang Xiaoshu Zhang 《Journal of Polyphenols》 2024年第3期91-97,共7页
Alcoholic liver injury is a liver disease caused by excessive alcohol consumption,which can lead to chronic liver disease death.Solanum Nigrum Linn taste bitter,cold,has the effect of clearing heat and detoxification,... Alcoholic liver injury is a liver disease caused by excessive alcohol consumption,which can lead to chronic liver disease death.Solanum Nigrum Linn taste bitter,cold,has the effect of clearing heat and detoxification,promoting blood and detumescence.Solanum Nigrum Linn fruit contains a variety of antioxidant enzymes,can remove the body produced by aerobic metabolism harmful substances.In this paper,a model of alcohol-induced liver injury in C57BL/6 mice was established to evaluate the protective effect of Solanum Nigrum Linn green fruit(SNGF)ethanolic extract on alcohol-induced liver injury.H&E staining and oil red O(ORO)staining showed that hepatic lobules were clearly demarcated,vacuoles were significantly reduced and lipid droplets were reduced in SNGF ethanolic extract treatment group.Serum levels of TC,TG,LDH,TBA,AKP,ALT and AST were decreased in the SNGF ethanolic extract treatment group,and SNGF ethanolic extract could clear reactive oxygen species(ROS)in time.MDA content was signifi cantly decreased after SNGF ethanolic extract treatment,while superoxide dismutase(SOD)and GSH-Px contents were increased after SNGF ethanolic extract treatment.These results suggest that SNGF ethanolic extract has a protective effect on alcohol-induced liver injury. 展开更多
关键词 Solanum Nigrum Linn green fruit ethanolic extract alcoholic liver injury protective effect
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基于无人机果树冠层卷吸效应的窄弧扇形防漂移喷嘴设计
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作者 李毅轩 赵耀辉 汪星星 《农机化研究》 北大核心 2025年第1期79-86,共8页
针对植保无人机对果树冠层喷洒易产生的药液漂移问题,结合植保无人机对果树喷洒时产生的卷吸效应和扇形喷嘴雾化原理,设计了一种窄弧扇形喷嘴结构,并通过对不同冠层压力损失系数下的喷洒过程进行仿真分析,得到最佳防漂移的窄弧扇形喷嘴... 针对植保无人机对果树冠层喷洒易产生的药液漂移问题,结合植保无人机对果树喷洒时产生的卷吸效应和扇形喷嘴雾化原理,设计了一种窄弧扇形喷嘴结构,并通过对不同冠层压力损失系数下的喷洒过程进行仿真分析,得到最佳防漂移的窄弧扇形喷嘴结构参数。研究结果表明:喷嘴内径增大,液膜与液带结构趋于稳定,液滴分布均匀,沉积率呈先降后升趋势;冠层压力损失系数降低,粒径频谱宽度减小,但沉积率总体提高;对较厚冠层果树植保时,选择内径1.3 mm、狭缝宽度0.15 mm的喷嘴,防漂移性能较好;对较薄冠层果树植保时,选择内径1.03 mm、狭缝宽度0.2 mm的喷嘴,防漂移性能较好;采用窄弧扇形喷嘴的液滴频谱宽度>0.7,沉积率>94.1%。 展开更多
关键词 植保无人机 窄弧扇形喷嘴 卷吸效应 防漂移性能
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