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基于RIP1/RIP3/MLKL通路研究桑色素对缺血性脑卒中大鼠神经元坏死性凋亡的影响及作用机制
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作者 张超 李瑞青 +4 位作者 张丹莉 吕转 马素娜 吴新 任彬彬 《中草药》 北大核心 2025年第16期5847-5855,共9页
目的基于受体相互作用蛋白激酶1(receptor interacting protein kinase 1,RIP1)/RIP3/混合谱系激酶结构域样蛋白(mixed lineage kinase domain-like protein,MLKL)通路探讨桑色素对缺血性脑卒中(ischemic stroke,IS)大鼠神经元坏死性凋... 目的基于受体相互作用蛋白激酶1(receptor interacting protein kinase 1,RIP1)/RIP3/混合谱系激酶结构域样蛋白(mixed lineage kinase domain-like protein,MLKL)通路探讨桑色素对缺血性脑卒中(ischemic stroke,IS)大鼠神经元坏死性凋亡的影响。方法采用改良Zea-Longa法建立IS大鼠模型,将造模成功的大鼠随机分为模型组及桑色素低、高剂量(15、30 mg/kg)组和依达拉奉(1.35 mL/kg)组、桑色素(30 mg/kg)+重组蛋白RIP1(recombinant protein RIP1,rRIP1,8μg/kg)组,每组10只,另取10只正常大鼠作为假手术组。给予药物干预1周后,对大鼠进行神经功能损伤评分,测定脑梗死面积比;检测血清中炎症因子水平;采用苏木素-伊红(hematoxylin eosin,HE)和Nissl染色检测脑组织病理变化及神经元数目;采用免疫组化法检测脑组织小胶质细胞数量;采用免疫荧光法检测脑组织神经元核抗原(neuronal nucleoprotein,NeuN)表达;采用TUNEL染色检测神经元细胞凋亡情况;采用qRT-PCR检测脑组织B细胞淋巴瘤-2(B-cell lymphoma-2,Bcl-2)、Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)、活化的半胱氨酸天冬氨酸蛋白酶-3(cleaved cystein-asparate protease-3,cleaved Caspase-3)m RNA表达;采用Western blotting检测脑组织RIP1/RIP3/MLKL通路相关蛋白表达。结果与模型组比较,桑色素组神经功能损伤评分及血清中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-1β(interleukin-1β,IL-1β)水平和脑梗死面积百分比、脑组织小胶质细胞数、神经元细胞凋亡率显著降低(P<0.05),血清中IL-10水平、神经元数和NeuN表达显著升高(P<0.05),脑组织Bax m RNA表达、磷酸化RIP1(phosphorylated RIP1,p-RIP1)/RIP1、RIP3、MLKL蛋白表达水平显著下调(P<0.05),cleaved Caspase-3、Bcl-2 mRNA表达显著上调(P<0.05)。rRIP1可以显著逆转桑色素对IS大鼠的保护作用(P<0.05)。结论桑色素通过抑制RIP1/RIP3/MLKL通路改善IS大鼠神经元坏死性凋亡。 展开更多
关键词 缺血性脑卒中 桑色素 rip1/rip3/MLKL信号通路 神经元 坏死性凋亡
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RIP3参与的线粒体DNA-cGAS-STING信号通路在HK-2细胞缺氧-复氧模型中的作用
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作者 孔亚坤 王焕 +4 位作者 尹俊杰 熊承云 吴苏豫 张莹 赵建林 《郑州大学学报(医学版)》 北大核心 2025年第5期603-608,共6页
目的:探究RIP3参与的线粒体DNA(mtDNA)-cGAS-STING信号通路在HK-2缺氧-复氧(H-R)细胞模型中的作用机制。方法:构建H-R细胞模型,取对数生长期HK-2细胞,于无葡萄糖和血清的特殊培养基中缺氧培养3、6和12 h后复氧,同时设置对照组,采用MTT... 目的:探究RIP3参与的线粒体DNA(mtDNA)-cGAS-STING信号通路在HK-2缺氧-复氧(H-R)细胞模型中的作用机制。方法:构建H-R细胞模型,取对数生长期HK-2细胞,于无葡萄糖和血清的特殊培养基中缺氧培养3、6和12 h后复氧,同时设置对照组,采用MTT法检测细胞存活率,Western blot检测RIP3、cGAS、STING、TBK1、IRF3、IFN-α、IFN-β、TNF-α、IL-1β、NF-κB蛋白表达水平,RT-qPCR检测RIP3、cGAS、STING mRNA表达水平。细胞转染及加入RU.521(cGAS抑制剂)、Mito-TEMPO(线粒体ROS特异性清除剂)和溴化乙锭(EtBr)验证cGAS-STING信号通路激活机制,免疫荧光染色法测定mtDNA水平。结果:与对照组相比,H-R 3、6、12组细胞存活率均降低,mtDNA-cGAS-STING信号通路中相关蛋白RIP3、cGAS、STING、TBK1、IRF3、IFN-α、IFN-β、TNF-α、IL-1β、NF-κB及RIP3、STING mRNA表达水平均上升,H-R 6、12组cGAS mRNA表达水平均上升(P<0.05)。与H-R 12+si-NC组相比,H-R 12+si-cGAS组细胞存活率升高,RIP3、cGAS、STING mRNA表达水平均降低;与H-R 12组相比,H-R 12+RU.521组与H-R 12+Mito-TEMPO组RIP3、cGAS、STING、TBK1、IRF3、IFN-β和IL-1β蛋白表达水平均降低(P<0.05)。H-R处理12 h可增加胞质双链DNA且其与线粒体共定位,而EtBr处理可减少胞质mtDNA(P<0.05)。结论:H-R可影响HK-2细胞活力及mtDNA-cGAS-STING信号通路,cGAS在其中起重要作用,且胞质mtDNA对cGAS-STING轴有调节作用。 展开更多
关键词 缺氧-复氧 HK-2细胞 rip3 线粒体DNA-cGAS-STING信号通路
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HUMAN-IMITATING INTELLIGENT CONTROL AND TRIPLE INVERTED-PENDULUM 被引量:4
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作者 Zhang Minglian Hao Jiankang He Weidong (305, Department of Automatic Control, Beijing University of Aeronautics and Astronautics, Beijing, China, 100083)Sun Changling(Department of Automation, Tsinghua University, Beijing, China, 100084) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第2期135-146,共12页
A 'Human-Imitating Intelligent Control Theory' with 'generalized reduction' and 'Human Imitating' concepts as its kernel is proposed. And a world puzzlein the control circles is solved successf... A 'Human-Imitating Intelligent Control Theory' with 'generalized reduction' and 'Human Imitating' concepts as its kernel is proposed. And a world puzzlein the control circles is solved successfully based on this theory. The puzzle is thewell-known 'triple inverted pendulum control' using a SINGLE motor. A human-imitating intelligent technique to control inverted pendulum is here described. The success. ful experimental results show that our control objective can be achieved without a precise mathematical model of the plant. Finally, general principles of designing complexautomatic control systems based on the human-imitating intelligent control theory areconcluded. 展开更多
关键词 artificial intelligence pendulumS automatic control control systems design
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加味柴胡疏肝汤激活RIP1/RIP3/MLKL信号通路抑制癫痫小鼠海马细胞坏死性凋亡 被引量:1
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作者 谢苗莹 曾榕 +5 位作者 吴琼 陈江玮 梁霜 钟洁 罗玉珍 刁丽梅 《中华中医药学刊》 北大核心 2025年第4期144-148,I0030,共6页
目的探究加味柴胡疏肝汤通过RIP1/RIP3/MLKL通路对癫痫小鼠的调控作用。方法将60只KM小鼠随机分为空白组、模型组、加味柴胡疏肝汤低剂量组、加味柴胡疏肝汤中剂量组、加味柴胡疏肝汤高剂量组、卡马西平组。采用盐酸匹罗卡品制备癫痫模... 目的探究加味柴胡疏肝汤通过RIP1/RIP3/MLKL通路对癫痫小鼠的调控作用。方法将60只KM小鼠随机分为空白组、模型组、加味柴胡疏肝汤低剂量组、加味柴胡疏肝汤中剂量组、加味柴胡疏肝汤高剂量组、卡马西平组。采用盐酸匹罗卡品制备癫痫模型,予加味柴胡疏肝汤19.52、39.04、78.08 g/(kg·d),卡马西平30 mg/(kg·d),连续灌胃2周,观察小鼠一般情况;脑电波情况;苏木素-伊红(HE)染色观察病理形态学改变;原位末端转移酶标记技术(TUNEL)检测神经细胞凋亡率;实时定量反转录聚合酶链式反应(qRT-PCR)及蛋白质印迹(Western Blot)检测小鼠海马组织RIP1、RIP3、MLKL、TNF-α、IL-1β、IL-6的mRNA和蛋白表达水平。结果与空白组相比,模型组小鼠体质量明显降低;脑电图可以明显观测到连续发作的痫样波;HE染色可见较多神经元固缩,细胞体积减小,形态呈不规则状,胞核、胞质分界不清,染色加深;凋亡细胞阳性率明显提高;RIP1、RIP3、MLKL、TNF-α、IL-1β、IL-6mRNA和蛋白的相对表达量明显增高。各组经药物治疗之后,小鼠体质量较模型组稍有增加;脑电波痫性放电频次及强度明显减少;加味柴胡疏肝汤中剂量、加味柴胡疏肝汤高剂量组、卡马西平组凋亡细胞阳性率明显低于模型组,差异有统计学意义;加味柴胡疏肝汤高剂量组、卡马西平组的RIP1、RIP3、MLKL、TNF-α、IL-1β、IL-6mRNA和蛋白的相对表达量明显低于模型组,差异具有统计学意义。结论加味柴胡疏肝汤可能通过RIP1/RIP3/MLKL信号通路发挥抗癫痫作用。 展开更多
关键词 加味柴胡疏肝汤 癫痫 rip1/rip3/MLKL信号通路 坏死性凋亡
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Bilinear Model Proposal for Seismic Analysis Using Triple Friction Pendulum (TFP) Bearings
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作者 Iván Delgado Roberto Aguiar Pablo Caiza 《Open Journal of Civil Engineering》 2017年第1期14-31,共18页
An analytical model is presented for seismic analysis of triple friction pendulum bearings and validated using 81 bearing tests, each subjected to three cycles, with a duration of 12 seconds and using 250, 200 and 100... An analytical model is presented for seismic analysis of triple friction pendulum bearings and validated using 81 bearing tests, each subjected to three cycles, with a duration of 12 seconds and using 250, 200 and 100 tons vertical loads. The main objective is to develop formulas for bilinear behavior using maximum, average and minimum friction coefficients to check which is the closest to the real behavior in the laboratory tests and comparatives curves plotting to observe the standard derivation. Parameters such as friction coefficients, effective stiffness, damping factor and vibration periods are analyzed to understand the structural behavior of the TPF bearings. 展开更多
关键词 TripLE FRICTION pendulum Bearings
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麻黄碱调节RIP1/RIP3/MLKL信号通路对OGD/R诱导的神经元损伤的影响
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作者 李鹏 李爱歆 郭思佳 《中国免疫学杂志》 北大核心 2025年第9期2161-2165,2171,共6页
目的:探究麻黄碱调节受体相互作用蛋白1/受体相互作用蛋白3/混合谱系激酶结构域样蛋白(RIP1/RIP3/MLKL)信号通路对氧糖剥夺/复氧(OGD/R)诱导的神经元损伤的影响。方法:通过缺氧复氧构建OGD/R细胞模型;将人皮质神经元HCN细胞分为对照组... 目的:探究麻黄碱调节受体相互作用蛋白1/受体相互作用蛋白3/混合谱系激酶结构域样蛋白(RIP1/RIP3/MLKL)信号通路对氧糖剥夺/复氧(OGD/R)诱导的神经元损伤的影响。方法:通过缺氧复氧构建OGD/R细胞模型;将人皮质神经元HCN细胞分为对照组、模型组(OGD/R组)、麻黄碱组(800μg/ml)、Compound 6i组(RIP1激活剂Compound 6i,0.94μmol/L)、麻黄碱+Compound 6i组(800μg/ml麻黄碱+0.94μmol/L Compound 6i)、Nec-1组(RIP1特异性抑制剂Nec-1,5μmol/L)、麻黄碱+Nec-1组(800μg/ml麻黄碱+5μmol/L Nec-1);CCK-8法检测HCN细胞增殖;DCFH-DA法检测HCN细胞ROS水平;流式细胞术检测HCN细胞凋亡;ELISA检测TNF-α、IL-6水平;Western blot检测HCN细胞中RIP1/RIP3/MLKL信号通路及凋亡蛋白表达。结果:与对照组比较,OGD/R组HCN细胞ROS水平、细胞凋亡率、p-MLKL、RIP3、Bax、IL-6、TNF-α、RIP1表达显著升高,A450值、Bcl-2蛋白显著降低(P<0.05);与OGD/R组比较,麻黄碱组、Nec-1组HCN细胞ROS水平、细胞凋亡率、p-MLKL、RIP3、Bax、IL-6、TNF-α、RIP1表达显著降低,A450值、Bcl-2蛋白显著升高,Compound 6i组趋势与之相反(P<0.05);Compound 6i可减弱麻黄碱改善OGD/R诱导的神经元损伤的作用,Nec-1可增强麻黄碱改善OGD/R诱导的神经元损伤的作用。结论:麻黄碱通过抑制RIP1/RIP3/MLKL信号通路减轻OGD/R诱导的神经元损伤。 展开更多
关键词 麻黄碱 rip1/rip3/MLKL OGD/R 增殖 凋亡 神经元
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Simulation of a Triple Inverted Pendulum Based on Fuzzy Control
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作者 Wei Chen Nkurunziza Theodomile 《World Journal of Engineering and Technology》 2016年第2期267-272,共6页
The inverted pendulum is a classic problem in dynamics and control theory and is widely used as a benchmark for testing control algorithms. This paper studies the use of fuzzy control method to study the stability con... The inverted pendulum is a classic problem in dynamics and control theory and is widely used as a benchmark for testing control algorithms. This paper studies the use of fuzzy control method to study the stability control problem of a triple inverted pendulum system. By the linear model of the system, the feedback weight matrix of the LQR optimal control and the feedback parameters of the linear optimal control are designed to determine the parameters of the fuzzy controller. The simulation results show that the proposed method can achieve the stability control of the three stage inverted pendulum, and has good dynamic performance with simple parameter selection. 展开更多
关键词 Triple Inverted pendulum Fuzzy Control LQR Matlab Simulation
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基于NOD1/RIP2/NF-κB信号通路探讨“秩边透水道”针法对原发性痛经大鼠的镇痛作用 被引量:4
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作者 金旭 张艳林 +5 位作者 常博雅 任佳 郝健亨 曹玉霞 王海军 冀来喜 《中国针灸》 北大核心 2025年第2期209-216,共8页
目的:观察“秩边透水道”针法对原发性痛经(PD)大鼠核苷酸结合寡聚化结构域1(NOD1)/受体相互作用蛋白2(RIP2)/核转录因子κB(NF-κB)信号通路相关蛋白和促炎细胞因子表达的影响,探讨其缓解PD疼痛的可能机制。方法:将30只SPF级雌性SD大鼠... 目的:观察“秩边透水道”针法对原发性痛经(PD)大鼠核苷酸结合寡聚化结构域1(NOD1)/受体相互作用蛋白2(RIP2)/核转录因子κB(NF-κB)信号通路相关蛋白和促炎细胞因子表达的影响,探讨其缓解PD疼痛的可能机制。方法:将30只SPF级雌性SD大鼠(动情周期正常)随机分为空白组、模型组和针刺组,每组10只。模型组和针刺组大鼠采用苯甲酸雌二醇联合缩宫素腹腔注射法制备PD模型,针刺组大鼠在造模同时予“秩边透水道”针法干预,每次20 min,每天1次,连续10 d。于第11天观察各组大鼠腹腔注射缩宫素注射液30 min内扭体反应(扭体潜伏期、扭体次数、扭体评分);HE染色法观察大鼠子宫组织形态;ELISA法检测大鼠血清前列腺素E_(2)(PGE_(2))、前列腺素F_(2α)(PGF_(2α))、白细胞介素(IL)-1β、IL-18、环氧合酶-2(COX-2)、肿瘤坏死因子-α(TNF-α)含量;Western blot法检测各组大鼠子宫组织NOD1、RIP2、NF-κB p65、磷酸化核转录因子κB p65(p-NF-κB p65)蛋白表达;实时荧光定量PCR法检测各组大鼠子宫组织NOD1、RIP2、NF-κBp65m RNA表达。结果:与空白组比较,模型组大鼠扭体潜伏期延长(P<0.01),扭体次数增加及扭体评分升高(P<0.01);子宫内膜上皮细胞大量变性、坏死,子宫内膜严重水肿且大范围脱落,伴有中性粒细胞浸润;血清PGE2含量降低(P<0.01),血清PGF2α、IL-1β、IL-18、COX-2、TNF-α含量升高(P<0.01);子宫组织NOD1、RIP2、NF-κBp65、p-NF-κBp65蛋白表达及NOD1、RIP2、NF-κB p65 mRNA表达升高(P<0.01)。与模型组比较,针刺组大鼠扭体潜伏期延长(P<0.01),扭体次数减少及扭体评分降低(P<0.01);子宫内膜上皮组织少量变性、坏死,子宫内膜轻度水肿,少有中性粒细胞浸润;血清PGE2含量升高(P<0.01),血清PGF2α、IL-1β、IL-18、COX-2、TNF-α含量降低(P<0.01);子宫组织NOD1、RIP2、NF-κB p65、p-NF-κB p65蛋白表达及NOD1、RIP2、NF-κB p65 mRNA表达降低(P<0.05,P<0.01)。结论:“秩边透水道”针法能够缓解PD大鼠的疼痛症状,其作用机制可能与抑制PD大鼠子宫组织中NOD1/RIP2/NF-κB信号通路的活性,进而减轻其炎性反应有关。 展开更多
关键词 原发性痛经 针刺 秩边透水道 NOD1/rip2/NF-κB信号通路 炎性反应 疼痛
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基于NOD1介导的RIP2/NF-κB信号通路探讨眼针改善脑缺血再灌注损伤大鼠神经元自噬性损伤的作用机制
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作者 张新宇 马贤德 +4 位作者 樊程程 王奡 徐畅 王哲 张威 《中国中医药信息杂志》 2025年第12期106-112,共7页
目的 观察眼针干预对脑缺血再灌注损伤(CIRI)大鼠大脑皮质核苷酸结合寡聚化结构域受体1(NOD1)及其介导的RIP2/NF-κB信号通路相关蛋白和自噬相关蛋白表达的影响,探究眼针缓解CIRI的可能机制。方法 将SPF级雄性Wistar大鼠随机分为空白对... 目的 观察眼针干预对脑缺血再灌注损伤(CIRI)大鼠大脑皮质核苷酸结合寡聚化结构域受体1(NOD1)及其介导的RIP2/NF-κB信号通路相关蛋白和自噬相关蛋白表达的影响,探究眼针缓解CIRI的可能机制。方法 将SPF级雄性Wistar大鼠随机分为空白对照组12只、假手术组12只、造模组36只,采用改良线栓法建立CIRI模型,将造模组随机分为模型组、眼针组、穴区外组,每组12只。采用Longa评分法评价大鼠神经功能缺损情况,TTC染色观察大鼠脑梗死情况,HE染色观察缺血区脑组织形态,电镜观察缺血区脑组织自噬小体形成情况,RT-qPCR检测缺血区大脑皮质NOD1、受体相互作用蛋白2(RIP2)、核因子-κB(NF-κB)p65 mRNA表达,Western blot检测缺血区大脑皮质NOD1、RIP2、NF-κB p65及自噬相关蛋白表达。结果 与假手术组比较,模型组大鼠神经功能缺损评分显著升高(P<0.01),脑梗死体积显著增加(P<0.01),缺血区脑组织可见典型筛网状梗死灶和多个自噬小体,缺血区大脑皮质NOD1、RIP2、NF-κB p65 mRNA表达显著升高(P<0.01),NOD1、RIP2、p-NF-κB p65、Beclin1、LC3Ⅱ/LC3Ⅰ、ATG5蛋白表达显著升高(P<0.01),p62蛋白表达显著降低(P<0.01);与模型组比较,眼针组大鼠神经功能缺损评分显著降低(P<0.01),脑梗死体积显著缩小(P<0.01),缺血区脑组织筛网状梗死灶面积明显减小,自噬小体数量减少,缺血区大脑皮质NOD1、RIP2、NF-κB p65 mRNA表达显著降低(P<0.01),NOD1、RIP2、p-NF-κB p65、Beclin1、LC3Ⅱ/LC3Ⅰ、ATG5蛋白表达显著降低(P<0.01),p62蛋白表达显著升高(P<0.01)。穴区外组各指标差异无统计学意义。结论 眼针可减轻CIRI大鼠神经元损伤,其作用机制可能与抑制NOD1介导的RIP2/NF-κB信号通路激活,进而减轻神经元自噬有关。 展开更多
关键词 眼针 脑缺血再灌注损伤 核苷酸结合寡聚化结构域受体1 rip2/NF-κB信号通路 自噬 大鼠
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Metformin Induces Non-small Cell Lung Cancer Cells Apoptosis Depending on AMPK-mediated RIP1 Downregulation
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作者 LI Min SHI Shao-Qing ZHENG Yuan-Yuan 《中国生物化学与分子生物学报》 北大核心 2025年第4期551-559,共9页
The incidence and mortality rate of lung cancer rank among the highest worldwide,severely endangering human health and life.Metformin,an anti-diabetes drug,has been shown to elicit anticancer activities in various tum... The incidence and mortality rate of lung cancer rank among the highest worldwide,severely endangering human health and life.Metformin,an anti-diabetes drug,has been shown to elicit anticancer activities in various tumors.However,its underlying mechanisms remain elusive.In this work,we explore the role of receptor-interacting protein 1(RIP1)which plays a crucial role in the process of cell death,in metformin-induced anticancer activities in lung cancer.Metformin inhibits lung cancer cell proliferation in a dose-dependent manner and promotes apoptotic cell death,as evidenced by metformin-induced PARP and caspase cleavage.Furthermore,the pan-caspase inhibitor z-VAD-fmk reverses metformin-induced cell death.Western blot and qPCR results suggest that metformin markedly downregulates RIP1 expression without affecting its mRNA and ubiquitination levels(0 vs 80 mmol/L,100%vs 20%,100%vs 15%).Additionally,co-immunoprecipitation and immunofluorescence results reveal that metformin may suppress RIP1 expression in an Hsp70-dependent manner,as metformin promotes Hsp70 degradation,and Hsp70 endogenously interacts with RIP1.Subsequent CCK-8,flow cytometry,and Western blot analyses suggest that metformin decreases Hsp70/RIP1 expression through AMPK/PKA/GSK-3βaxis.Consistently,results from a subcutaneous transplant tumor model indicate that metformin retards tumor growth without affecting mouse body weight.Collectively,these data highlight the part of RIP1 in metformin-induced anticancer activities in lung cancer in vitro and in vivo,providing novel strategy for lung cancer administration. 展开更多
关键词 lung cancer METFORMIN receptor-interacting protein 1(rip1) heatshockprotein70(Hsp70) AMP-activated protein kinas(AMPK)
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Gravity well-inspired double friction pendulum system for bridges under pulse-like near-fault earthquakes
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作者 Sasa Cao Osman E.Ozbulut 《Resilient Cities and Structures》 2025年第1期83-100,共18页
When a coin is tossed to a gravity well,it will spiral instead of falling directly to the center.Inspired by this phenomenon,a gravity well-inspired double friction pendulum system(GW-DFPS)is developed to extend the l... When a coin is tossed to a gravity well,it will spiral instead of falling directly to the center.Inspired by this phenomenon,a gravity well-inspired double friction pendulum system(GW-DFPS)is developed to extend the length of sliding trajectories of bridge superstructures during pulse-like near-fault earthquakes.As a result,a greater amount of energy will be dissipated due to the frictional sliding of the isolators.The GW-DFPS consists of a spherical surface and an outer surface described by a 1/x or logarithmic function to build gravity well.Full-scale isolators were fabricated and their response was characterized considering various parameters such as the friction material of slider,surface roughness of sliding surfaces,and applied vertical loads.Additionally,a finite element model of the isolator was created using the experimental test data.Numerical simulations were performed on a case-study bridge structure isolated using both a conventional DFPS system and the proposed GW-DFPS systems.The experimental results reveal that the proposed isolators exhibit stable response under vertical loads varying from 200 kN to 1000 kN with a negative stiffness response when the isolator slides at the outer sliding surface.The numerical simulations of the selected bridge structure demonstrate that the GW-DFPS significantly extends the sliding trajectory lengths of the superstructure during half of the earthquake pulses,resulting in increased energy dissipation during this interval.The kinetic energies of the bridge isolated by GW-DFPS are consistently lower than those of the bridge isolated by the other two kinds of isolators,resulting lower shear forces on the bridge. 展开更多
关键词 Friction pendulum bearing Gravity well TRAJECTORY EARTHQUAKES BRIDGES
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益母草碱通过调节RIP1-RIP3-MLKL通路改善心肌缺血/再灌注损伤大鼠坏死性凋亡
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作者 李明芳 唐碧波 +1 位作者 杨才进 刘超权 《中国免疫学杂志》 北大核心 2025年第8期1879-1884,共6页
目的:探讨益母草碱(Leo)通过调节受体相互作用蛋白1(RIP1)-受体相互作用蛋白3(RIP3)-混合谱系激酶结构域样蛋白(MLKL)通路对心肌缺血/再灌注(MIR)损伤大鼠坏死性凋亡的影响。方法:随机取15只大鼠作为假手术组(Sham),其余大鼠结扎左冠状... 目的:探讨益母草碱(Leo)通过调节受体相互作用蛋白1(RIP1)-受体相互作用蛋白3(RIP3)-混合谱系激酶结构域样蛋白(MLKL)通路对心肌缺血/再灌注(MIR)损伤大鼠坏死性凋亡的影响。方法:随机取15只大鼠作为假手术组(Sham),其余大鼠结扎左冠状动脉前降支构建MIR模型后随机分为MIR组、Leo组(15 mg/kg)、Compound 6i组(1 mg/kg RIP1-RIP3-MLKL通路激活剂Compound 6i)、Leo+Compound 6i组(15 mg/kg Leo+1 mg/kg Compound 6i),每组15只。MIR组和Sham组注射等量生理盐水。超声心电图观察心功能指标;ELISA检测心肌损伤指标及炎症因子水平;HE染色观察心脏病理损伤情况;TTC染色检测心肌梗死面积;TUNEL染色检测细胞凋亡;Western blot检测RIP1-RIP3-MLKL通路蛋白表达。结果:Sham组大鼠心肌细胞完整,排列有序;MIR组心肌细胞排列紊乱和肿胀,肌原纤维收缩,肌膜被破坏,较Sham组射血分数(EF)及心输出量(CO)水平显著降低(P<0.05),Mb、cTnⅠ、CK-Mb含量、IL-6、IL-18水平、心肌梗死面积、心肌细胞凋亡率、RIP1、RIP3及MLKL蛋白水平显著升高(P<0.05);与MIR组相比较,Leo组细胞排列杂乱和水肿现象改善,EF、CO水平显著升高(P<0.05),Mb、cTnⅠ、CK-Mb含量、IL-6、IL-18水平、心肌梗死面积、心肌细胞凋亡率、RIP1、RIP3及MLKL蛋白水平显著降低(P<0.05),而Compound 6i组趋势相反;Leo+Compound 6i组与MIR组心肌组织结构相似,Compound 6i消除了Leo对MIR大鼠的心脏保护作用。结论:Leo可能通过下调RIP1-RIP3-MLKL通路缓解MIR大鼠心肌细胞坏死性凋亡,进而对MIR起治疗效果。 展开更多
关键词 益母草碱 rip1-rip3-MLKL通路 心肌缺血再灌注 坏死性凋亡
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Precision assessment of micro-thruster performance: A comparative study of indium field emission electric propulsion thrust measurement methods with a force-feedback pendulum
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作者 Bo-Song Cai Yan Shen +5 位作者 Yuan Zhong Jian-Ping Liu Yu-Qing Wang Zhu Li Liang-Cheng Tu Shan-Qing Yang 《Chinese Physics B》 2025年第4期132-141,共10页
Accurate thrust assessment is crucial for characterizing the performance of micro-thrusters.This paper presents a comprehensive evaluation of the thrust generated by a needle-type indium field emission electric propul... Accurate thrust assessment is crucial for characterizing the performance of micro-thrusters.This paper presents a comprehensive evaluation of the thrust generated by a needle-type indium field emission electric propulsion(In-FEEP)micro-thruster using three methods based on a pendulum:direct thrust measurement,indirect plume momentum transfer and beam current diagnostics.The experimental setup utilized capacitive displacement sensors for force detection and a voice coil motor as a feedback actuator,achieving a resolution better than 0.1μN.Key performance factors such as ionization and plume divergence of ejected charged particles were also examined.The study reveals that the high applied voltage induces significant electrostatic interference,becoming the dominant source of error in direct thrust measurements.Beam current diagnostics and indirect plume momentum measurements were conducted simultaneously,showing strong agreement within a deviation of less than 0.2N across the operational thrust range.The results from all three methods are consistent within the error margins,verifying the reliability of the indirect measurement approach and the theoretical thrust model based on the electrical parameters of In-FEEP. 展开更多
关键词 MICRO-THRUSTER field emission thrust stand micro-thrust measurement calibration pendulum
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Development of a Two-Dimensional Hydrodynamic Model to Simulate Rip Currents in the Bai Dai-Cam Ranh Coast, Vietnam
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作者 Ngo Nam Thinh Nguyen Thi Bay 《Journal of Environmental & Earth Sciences》 2025年第4期203-216,共14页
Rip currents are a significant threat to swimmers worldwide,responsible for numerous drowning incidents each year.In Vietnam,Bai Dai Beach in Cam Ranh Bay,Khanh Hoa Province,has experienced an increase in drowning eve... Rip currents are a significant threat to swimmers worldwide,responsible for numerous drowning incidents each year.In Vietnam,Bai Dai Beach in Cam Ranh Bay,Khanh Hoa Province,has experienced an increase in drowning events due to rip currents in recent years.To address this issue,a comprehensive study was conducted based on developing a depth-averaged 2D hydrodynamic model to simulate rip currents in the Bai Dai-Cam Ranh coast.The HYDIST-2D numerical model was applied to simulate the rip current evolution in space and time for the study area.The results showed that the HYDIST-2D numerical model can accurately predict the location,magnitude,and microstructure of rip currents,including rip current speed,width,and length.The simulation results revealed that the rip current speed is greater during the low tide phase,with an average speed of 0.5 m s^(-1),while during high tide,the rip current speed is lower,around 0.1–0.8 m s^(-1).The width and length of the rip current also vary with the tide phase,with a wider and longer rip current observed during the low tide phase.The results also showed that the rip current speed and microstructure are influenced by the wave features,tide current,and bathymetry of the study area.The present study provides valuable insights into the dynamics of rip currents in the Bai Dai-Cam Ranh coast.The findings can be used to support the management of bathing activities and provide early warnings for potential risks associated with rip currents. 展开更多
关键词 HYDIST Model SWIMMERS rip Hydrodynamic Factors Breaking Waves
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Pendulum routes in the Northeast Passage:design and economic analysis
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作者 HU Maixiu CHEN Yingying 《Advances in Polar Science》 2025年第3期191-202,共12页
Global warming has made the regular operation of Arctic routes possible.This study selects hub ports based on infrastructure conditions and sea ice status,and then designs two pendulum route solutions for the Northeas... Global warming has made the regular operation of Arctic routes possible.This study selects hub ports based on infrastructure conditions and sea ice status,and then designs two pendulum route solutions for the Northeast Passage according to the distance between hub ports and ice-covered areas.We employ an evaluation framework combining annual profit metrics with discounted net present value(NPV)analysis,conducting probabilistic economic assessments through Monte Carlo simulations(20,000 iterations).Key findings indicate that(1)both solutions demonstrate>90%probability of economic viability and(2)Solution I′,with hub ports closer to ice-covered areas than those in Solution II,yields 5.02%higher mean annual profit and 4.69%greater NPV.The results indicate that pendulum routes in the Northeast Passage can achieve economic benefits by enabling year-round regular operations.Moreover,shorter shipping distances between hub ports and ice-covered areas enhance economic viability. 展开更多
关键词 Northeast Passage(NEP) pendulum shipping route shipping economy Monte Carlo simulation
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基于HCL的RIP路由环路实验设计与分析
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作者 王永生 杜彬彬 +1 位作者 张龙杰 王浩栋 《数字技术与应用》 2025年第5期76-78,共3页
路由信息协议(Routing Information Protocol,RIP)是中小型计算机网络常用的路由协议,也是一种重要的基于距离矢量(Distance-Vector)算法的路由协议。本文利用华三HCL(H3C Cloud Lab)网络仿真软件,设计环状拓扑结构实验网络,配置网络路... 路由信息协议(Routing Information Protocol,RIP)是中小型计算机网络常用的路由协议,也是一种重要的基于距离矢量(Distance-Vector)算法的路由协议。本文利用华三HCL(H3C Cloud Lab)网络仿真软件,设计环状拓扑结构实验网络,配置网络路由协议RIP,抓取RIP数据报文,跟踪分析网络路由环路生成。通过实验及协议数据报分析,观察路由环路动态变化,有助于深入理解RIP防止路由环路机制,提高路由故障排查能力。 展开更多
关键词 路由信息协议 H3C Cloud Lab rip HCL
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An Inverted Pendulum System Control with Fuzzy Linear Quadratic Regulator Method:Experimental Validation
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作者 Tayfun Abut 《Computers, Materials & Continua》 2025年第11期4023-4042,共20页
In this study,a dynamic model for an inverted pendulum system(IPS)attached to a car is created,and two different control methods are applied to control the system.The designed control algorithms aim to stabilize the p... In this study,a dynamic model for an inverted pendulum system(IPS)attached to a car is created,and two different control methods are applied to control the system.The designed control algorithms aim to stabilize the pendulum arms in the upright position and the car to reach the equilibrium position.Grey Wolf Optimization-based Linear Quadratic Regulator(GWO-LQR)and GWO-based Fuzzy LQR(FLQR)control algorithms are used in the control process.To improve the performance of the LQR and FLQR methods,the optimum values of the coefficients corresponding to the foot points of the membership functions are determined by the GWO algorithm.Both a graphic and a numerical analysis of the outcomes are provided.In the comparative analysis,it is observed that the GWO-based FLQR method reduces the settling time by 22.58% and the maximum peak value by 18.2% when evaluated in terms of the angular response of the pendulum arm.Furthermore,this approach outperformed comparable research in the literature with a settling time of 2.4 s.These findings demonstrate that the suggested GWO-based FLQR controlmethod outperforms existing literature in terms of the time required for the pendulum arm to reach equilibrium. 展开更多
关键词 Fuzzy-linear quadratic regulator control grey wolf optimization algorithm inverted pendulum system linear quadratic regulator real-time control
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Calibration of Elastic-Plastic Degradation Model for 40Cr Steel Applied in Finite Element Simulation of Shear Pins of Friction Pendulum Bearings
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作者 Mianyue Yang Huasheng Sun Weigao Sheng 《Computers, Materials & Continua》 2025年第11期2749-2761,共13页
The shear pin of the friction pendulum bearing(FPB)can be made of 40Cr steel.In conceptual design,the optimal cut-off point of the shear pin is predetermined,guiding the design of bridges isolated by FPBs to maximize ... The shear pin of the friction pendulum bearing(FPB)can be made of 40Cr steel.In conceptual design,the optimal cut-off point of the shear pin is predetermined,guiding the design of bridges isolated by FPBs to maximize their isolation performance.Current researches on the shear pins are mainly based on linear elastic models,neglecting their plasticity,damage,and fracture mechanical properties.To accurately predict its cutoff behavior,the elastic-plastic degradationmodel of 40Cr steel is indeed calibrated.For this purpose,the Ramberg-Osgoodmodel,the Bao-Wierzbicki damage initiation criterion,and the linear damage evolution criterion were selected to develop the elastic-plastic degradation model of 40Cr.Subsequently,parameter calibration of this model was performed through uniaxial tensile tests on two sets of six smooth,round bars with different diameters.Following this,finite element simulations were conducted for the pure shear test of grade 10.9 high-strength bolts made of 40Cr steel,aiming to verify the elasticplastic degradation model.The results showed that the failure modes and force-displacement curves simulated by the finite element method were in good agreement with the test results.Moreover,the error between the primary characteristic parameters(initial stiffness,peak load,fracture displacement,and absorbed energy)obtained by finite element calculation and the test values was within 15%.These results demonstrated that the calibration elastic-plastic degradation model of 40Cr steel can predict the cutoff of the shear pin. 展开更多
关键词 Friction pendulum bearing shear pin 40Cr steel elastic-plastic degradationmodel uniaxial tensile test parameters calibration
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RIP套管在运行中的问题及处理
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作者 葛乃军 《内江科技》 2025年第1期8-10,110,共4页
主要探讨了RIP套管在运行中的问题及处理方法。首先介绍了RIP套管的基本结构和工作原理,并阐述了其在电力系统中的重要性和应用范围;然后详细分析了RIP套管在运行过程中可能遇到的问题,如温度升高、电压过大、湿度变化等,接着提出解决方... 主要探讨了RIP套管在运行中的问题及处理方法。首先介绍了RIP套管的基本结构和工作原理,并阐述了其在电力系统中的重要性和应用范围;然后详细分析了RIP套管在运行过程中可能遇到的问题,如温度升高、电压过大、湿度变化等,接着提出解决方案,包括合理的材料选择、制造工艺改进以及严格的检测和维护措施等,以期对未来的研究方向提供参考。 展开更多
关键词 rip 湿度变化 维护措施 问题及处理 套管 制造工艺改进 解决方案 运行过程
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二体微振动在晶格振动教学中的应用
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作者 樊志琴 李瑞 胡克凡 《物理通报》 2026年第1期6-9,共4页
晶格振动是一个非常庞大的多自由度体系的简谐振动问题.从分析力学中的二体微振动耦合振子和双单摆入手,从简至繁地逐步阐明晶格振动中的简正坐标、简正振动与正交变换等一些概念及其物理意义.
关键词 耦合振子 双单摆 正交变换 简正振动 简正坐标
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