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Re-entry gliding vehicle trajectory prediction based on maneuver detection
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作者 HU Yudong PANG Maofeng +1 位作者 DU Qingfeng GAO Changsheng 《Journal of Systems Engineering and Electronics》 2026年第1期9-17,共9页
Re-entry gliding vehicles exhibit high maneuverability,making trajectory prediction a key factor in the effectiveness of defense systems.To overcome the limited fitting accuracy of existing methods and their poor adap... Re-entry gliding vehicles exhibit high maneuverability,making trajectory prediction a key factor in the effectiveness of defense systems.To overcome the limited fitting accuracy of existing methods and their poor adaptability to maneuver mode mutations,a trajectory prediction method is proposed that integrates online maneuver mode identification with dynamic modeling.Characteristic parameters are extracted from tracking data for parameterized modeling,enabling real-time identification of maneuver modes.In addition,a maneuver detection mechanism based on higher-order cumulants is introduced to detect lateral maneuver mutations and optimize the use of historical data.Simulation results show that the proposed method achieves accurate trajectory prediction during the glide phase and maintains high accuracy under maneuver mutations,significantly enhancing the prediction performance of both three-dimensional trajectories and ground tracks. 展开更多
关键词 trajectory prediction re-entry gliding vehicle maneuver mode identification maneuver detection
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Curcumin attenuates pressure overload-induced cardiac fibrosis in mice via modulating the miR-29b/HDAC4 axis
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作者 Yu Xiang Ying Lv +2 位作者 Xiao-Xiang Liu Bo-Tao Li Jing Liu 《Asian Pacific Journal of Tropical Biomedicine》 2026年第2期59-67,I0001,I0002,共11页
Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low... Objective:To investigate the antifibrotic effects of curcumin in a transverse aortic constriction(TAC)mouse model and elucidate its molecular mechanisms.Methods:Male C57BL/6 mice underwent TAC and received vehicle,low-dose curcumin(50 mg/kg),high-dose curcumin(200 mg/kg),high-dose curcumin plus a scrambled control antagomir,or high-dose curcumin plus anti-miR-29b treatments.Cardiac function was assessed by echocardiography.Fibrosis was evaluated by histology,collagen volume fraction,and hydroxyproline content.Expression of miR-29b,HDAC4,and fibrosis-related markers(Col1a1,Col3a1,TGF-β1)was measured by quantitative RT-PCR and Western blotting assays.Myocardial procollagen type I carboxy-terminal propeptide was determined by ELISA,and HDAC4-specific enzymatic activity was assayed using a fluorogenic kit.Results:Curcumin improved cardiac function,reduced fibrosis,restored miR-29b expression,and suppressed HDAC4 expression and activity in a dose-dependent manner.Furthermore,curcumin decreased myocardial procollagen type I carboxy-terminal propeptide levels,confirming reduced collagen synthesis.Anti-miR-29b administration partially abrogated the antifibrotic and cardioprotective effects of curcumin.Conclusions:Curcumin attenuates pressure overload-induced cardiac fibrosis and dysfunction in a TAC mouse model via modulation of the miR-29b/HDAC4 axis and suppression of collagen synthesis. 展开更多
关键词 CURCUMIN Cardiac fibrosis MiR-29b HDAC4 Heart failure Pressure overload
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Remission of iron overload in adipose tissue of obese mice by fatty acid-modified polyoxovanadates
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作者 Kun Chen Yu-Rong Qin +1 位作者 Sheng-Qiu Liu Rou-Ling Chen 《Rare Metals》 2025年第1期461-471,共11页
Iron overload has been evidenced to contribute to obesity-associated metabolic disorders,including insulin resistance.Strategies to reduce iron levels might help manage the metabolic complications associated with obes... Iron overload has been evidenced to contribute to obesity-associated metabolic disorders,including insulin resistance.Strategies to reduce iron levels might help manage the metabolic complications associated with obesity.Here,it is demonstrated that the specific accumulation of oleic acid-modified polyoxovanadates(OPOVs)in adipose tissue leads to the reduction of iron concentrations in adipocytes in mice fed with a high-fat diet(HFD).Conjugation of oleic acids to polyoxovanadates enables tissue-specific depletion of iron from white adipose tissue(WAT)by OPOVs,protecting mice from HFD-induced obesity and obesity-associated metabolic deteriorations.Glucose tolerance and insulin sensitivity are improved in OPOV-treated mice,which demonstrates that the OPOV-induced iron depletion can reverse the metabolic degeneration caused by HFD-induced obesity.Furthermore,a decrease in expression of the marker genes of iron overload suggests the participation of OPOVs in maintaining iron homeostasis and a potential medical application of vanadium clusters in targeting the iron overload caused by obesity.These findings underscore the potential of vanadate-based clusters tailored to address the complex interplay between iron metabolism and metabolic health. 展开更多
关键词 POLYOXOVANADATES Lipophilic conjugation Obesity Iron overload Insulin resistance
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Combinatorial approach to treat iron overload cardiomyopathy in pediatric patients with thalassemia-major: A systematic review and meta-analysis
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作者 Moaz Safwan Mariam Safwan Bourgleh +1 位作者 Aseel Alsudays Khawaja Husnain Haider 《World Journal of Cardiology》 2025年第2期93-102,共10页
BACKGROUND Iron overload cardiomyopathy is a significant cause of morbidity and mortality in transfusion-dependent thalassemia patients.Standard iron chelation therapy is less efficient in alleviating iron accumulatio... BACKGROUND Iron overload cardiomyopathy is a significant cause of morbidity and mortality in transfusion-dependent thalassemia patients.Standard iron chelation therapy is less efficient in alleviating iron accumulation in many organs,especially when iron enters the cells via specific calcium channels.AIM To validate our hypothesis that adding amlodipine to the iron chelation regimen is more efficient in alleviating myocardial iron overload.METHODS Five databases,including PubMed,Cochrane Library,Embase,ScienceDirect,and ClinicalTrials.gov,were systematically searched,and three randomized controlled trials involving 144 pediatric patients with transfusion-dependent thalassemia were included in our meta-analysis based on the predefined eligibility criteria.The quality of the included studies was assessed based on the Cochrane collab-oration tool for bias assessment.The primary outcome assessed was myocardial-T2 and myocardial iron concentration,while the secondary results showed serum ferritin level,liver iron concentration,and treatment adverse outcomes.Weighted mean difference and odds ratio were calculated to measure the changes in the estimated treatment effects.RESULTS During the follow-up period,Amlodipine treatment significantly improved cardiac T2 by 2.79 ms compared to the control group[95%confidence interval(CI):0.34-5.24,P=0.03,I2=0%].Additionally,a significant reduction of 0.31 in myocardial iron concentration was observed with amlodipine treatment compared to the control group[95%CI:-0.38-(-0.25),P<0.00001,I2=0%].Liver iron concentration was slightly lower in the amlodipine group by-0.04 mg/g,but this difference was not statistically significant(95%CI:-0.33-0.24,P=0.77,I2=0%).Amlodipine also showed a non-significant trend toward a reduction in serum ferritin levels(-328.86 ng/mL,95%CI:-1212.34-554.62,P=0.47,I2=90%).Regarding safety,there were no significant differences between the groups in the incidence of gastrointestinal upset,hypotension,or lower limb edema.CONCLUSION Amlodipine with iron chelation therapy significantly improved cardiac parameters,including cardiac-T2 and myocardial iron,in patients with transfusion-dependent thalassemia without causing significant adverse events but enhancing the efficacy of iron chelation therapy. 展开更多
关键词 AMLODIPINE CARDIOMYOPATHY Iron overload Randomized controlled trials THALASSEMIA
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Numerical study on the failure characteristics and reinforcement effects of shield segmental linings subjected to localized overload
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作者 Long ZHOU Zhiguo YAN Mengqi ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第10期950-966,共17页
When only a portion of the shield lining structures in a full-line tunnel are overloaded,their bearing and failure characteristics are significantly different from those in the full-line overloaded case.In existing st... When only a portion of the shield lining structures in a full-line tunnel are overloaded,their bearing and failure characteristics are significantly different from those in the full-line overloaded case.In existing studies,one or several segmental lining rings have been studied,with overload applied to selected lining rings to analyze the performance evolution of the lining structures;however,this approach fails to reveal the bearing and failure characteristics of shield lining rings under localized overload.To address this research gap,we employ 3D finite element modeling to investigate the mechanical performance and failure mechanisms of shield segmental linings under localized overload conditions,and compare the results with full-line overload scenarios.Additionally,the impact of reinforcing shield segmental linings with steel rings is studied to address issues arising from localized overloads.The results indicate that localized overloads lead to significant ring joint dislocation and higher stress on longitudinal bolts,potentially causing longitudinal bolt failure.Furthermore,the overall deformation of lining rings,segmental joint opening,and stress in circumferential bolts and steel bars is lower compared to full-line overloads.For the same overload level,the convergence deformation of the lining under full-line overload is 1.5 to 2.0 times higher than that under localized overload.For localized overload situations,a reinforcement scheme with steel rings spanning across two adjacent lining rings is more effective than installing steel rings within individual lining rings.This spanning ring reinforcement strategy not only enhances the structural rigidity of each ring,but also limits joint dislocation and reduces stress on longitudinal bolts,with the reduction in maximum ring joint dislocation ranging from 70%to 82%and the reduction in maximum longitudinal bolt stress ranging from 19%to 57%compared to reinforcement within rings. 展开更多
关键词 Shield segmental lining Localized overload Failure characteristics Steel ring reinforcement
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Three-body cooperative active defense guidance law with overload constraints:A small speed ratio perspective
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作者 Shuangxi LIU Zehuai LIN +3 位作者 Yichong WANG Wei HUANG Binbin YAN Yong LI 《Chinese Journal of Aeronautics》 2025年第2期226-243,共18页
In air combat,one effective way to counter an incoming missile attacking an aircraft is to launch a defense missile compared with traditional passive defense strategies such as decoy and electronic countermeasures.To ... In air combat,one effective way to counter an incoming missile attacking an aircraft is to launch a defense missile compared with traditional passive defense strategies such as decoy and electronic countermeasures.To address this issue,this paper proposes a three-body cooperative active defense guidance law with overload constraints from the perspective of a small speed ratio.First,a cooperative guidance-oriented model for active defense is established and linearized to provide a foundation for the design of the guidance law.Then,the essential quantity known as Zero-Effort-Miss(ZEM)is analyzed during the engagement process.In order to minimize the influence of inaccurate estimates of remaining flight time in the ZEM,the concept of Zero-Effort-Velocity(ZEV)is introduced.Subsequently,utilizing the sliding mode control method,the guidance law is designed by selecting the ZEM and ZEV as sliding mode surfaces,combined with the fast power reaching law,and its finite-time stability is analyzed using the Lyapunov method.Furthermore,to quantitatively evaluate the performance of the proposed active defense guidance law,the interception rendezvous angle index is introduced.The proposed active defense guidance law considers integrating information from the incoming missile,aircraft,and defense missile with fewer simplifications and assumptions,and ensures that the aircraft is effectively protected with less overload required for the defense missile.Finally,simulation experiments demonstrate the effectiveness and adaptability of the proposed active defense guidance law. 展开更多
关键词 Three-body active defense Cooperative guidance Guidance law overload constraint Small speed ratio Sliding mode control
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The Protective Effects of Quercetin on Ferritinophagy in Alcoholic-Induced Liver Iron Overload
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作者 You Jin Hong-mei Zeng +6 位作者 Chan Peng Jie Huang Shi-ting Huang Qian Zhang Hao-bin Yang Ping Yao Lan Ni 《Current Medical Science》 2025年第5期1148-1159,共12页
Objective Iron overload resulting from chronic alcohol consumption may aggravate liver damage,and the potential mechanisms involving ferritinophagic flux and the role of naturally occurring quercetin in alcohol-induce... Objective Iron overload resulting from chronic alcohol consumption may aggravate liver damage,and the potential mechanisms involving ferritinophagic flux and the role of naturally occurring quercetin in alcohol-induced liver disease remain unclear.Methods Adult male C57BL/6J mice were iso-calorically pair-fed with ethanol-containing Lieber De Carli liquid diets according to a chronic-plus-binge ethanol feeding protocol with either quercetin(100 mg/kg.bw)or iron-rich/limited treatment for 12 weeks,and liver damage,as well as the underlying mechanisms of lysosome-dependent ferritinophagy,was explored,following the study of ethanol-incubated HepG2 cells with specific pharmacological reagents or gene regulation in vitro.Results Chronic-plus-binge ethanol feeding led to an increase in the hepatosomatic ratio,hepatic lipid accumulation and triglyceride(TG)content of the mice and induced the release of alanine aminotransferase(ALT),aspartate transaminase(AST),and serum TG levels,which were normalized partially by quercetin treatment or iron limitation but worsened by iron supplementation.Similar findings were observed in vitro.Moreover,quercetin intervention alleviated iron deposition,inhibited the upregulation of p62 and downregulation of nuclear receptor coactivator 4(NCOA4)and microtubule-associated protein 1 light chain 3(LC3)-II,and blocked the colocalization of NCOA4 and ferritin heavy chain and the nuclear translocation of forkhead box protein O1(FOXO1)induced by ethanol.These effects were also observed when the cells were subjected to iron limitation but were abolished by iron supplementation,NCOA4 transfection,or AS1842856,a FOXO1 inhibitor.Conclusion Quercetin ameliorates secondary iron overload and subsequent liver damage caused by alcohol abuse by maintaining ferritinophagic flux and lysosome function via the FOXO1-TFEB NCOA4 signaling pathway. 展开更多
关键词 Alcoholic liver disease Iron overload QUERCETIN Ferritinophagy Nuclear receptor coactivator 4 Transcription factor EB
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基于SOR模型视角的多模态信息过载对驾驶行为的影响机制研究
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作者 孙丽璐 胡小伟 赵娟 《西南大学学报(自然科学版)》 北大核心 2026年第3期197-208,共12页
车载信息系统(in-vehicle information system,IVIS)通过多功能整合提升驾驶便利性,但多模态信息过载可能加剧认知负荷超额并威胁行车安全。为探究信息过载对危险驾驶行为的动态影响机制,基于刺激-有机体-反应(Stimulus-Organism-Respon... 车载信息系统(in-vehicle information system,IVIS)通过多功能整合提升驾驶便利性,但多模态信息过载可能加剧认知负荷超额并威胁行车安全。为探究信息过载对危险驾驶行为的动态影响机制,基于刺激-有机体-反应(Stimulus-Organism-Response,SOR)模型引入驾驶信息需求作为调节变量,在此基础上构建视觉/听觉信息过载、认知负荷、驾驶意图与行为的理论框架。基于438名中国电动汽车用户的横断面调查数据并结合结构方程建模的数据分析表明,视觉与听觉信息过载显著正向影响认知负荷,且直接驱动不安全驾驶意图。同时,中介分析表明,信息过载可以通过认知负荷和驾驶意图间接影响驾驶行为。驾驶信息需求负向调节不安全驾驶意图向行为的转化,驾驶信息需求越高的驾驶员,越易主动抑制危险驾驶行为的外化。本研究将驾驶信息需求纳入SOR框架,揭示了多模态信息过载的差异化机制,弥补了个体差异研究的不足,也为IVIS开发方与整车制造商提供了可行的优化路径,包括抬头显示屏(head-up display,HUD)信息筛选优先级策略、认知负荷监测。 展开更多
关键词 刺激-有机体-反应模型 多模态信息过载 认知负荷 结构方程模型 驾驶行为
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级联失效下考虑节点过载的作业车间云网络鲁棒性研究
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作者 单子丹 侯成 +1 位作者 陈佳鑫 邹昕彤 《计算机集成制造系统》 北大核心 2026年第1期241-257,共17页
为进一步探究级联失效下作业车间生产节点的故障传播及其对车间整体鲁棒性的影响,以复杂网络视角对节点过载下作业车间云网络的结构特性与演化行为进行分析。从生产设备过载失效、设备负荷上限以及按工序关系强度负载重分配3方面出发,... 为进一步探究级联失效下作业车间生产节点的故障传播及其对车间整体鲁棒性的影响,以复杂网络视角对节点过载下作业车间云网络的结构特性与演化行为进行分析。从生产设备过载失效、设备负荷上限以及按工序关系强度负载重分配3方面出发,提出一种考虑节点过载状态的作业车间云网络级联失效模型。以某生产车间为例,利用蓄意攻击和随机攻击的方式验证模型的有效性,并与经典的BA、ER网络作对比,运用数值仿真揭示各关键参数对级联失效下不同网络的鲁棒性影响。研究结果表明:相较于蓄意攻击,作业车间云网络在面对随机攻击时具有更强的鲁棒性。当负载可调参数和可调忍耐参数值一定时,通过调整作业车间云网络级联失效中过载节点的负载分布参数,可以得到较优的参数分配选择范围,从而遏制作业车间云网络级联故障的进一步扩散。不仅为级联失效下复杂网络鲁棒优化研究开拓了新领域,也为作业车间韧性的提升及可持续发展提供了新思路。 展开更多
关键词 级联失效 节点过载 作业车间 网络鲁棒性
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面向家庭电气火灾的交流线路故障模拟系统设计与试验验证
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作者 刘涛 魏宗峰 +2 位作者 郭宇航 唐海军 姜文涛 《消防科学与技术》 北大核心 2026年第1期21-27,34,共8页
电气火灾频发与交流线路故障密切相关,其中接地故障、过载运行及短路等隐性或突发性故障因传统监测手段存在响应滞后、风险识别精度不足等问题,成为火灾防治的难点。为此,本研究构建面向电气火灾防治的交流线路故障模拟系统,集成短路、... 电气火灾频发与交流线路故障密切相关,其中接地故障、过载运行及短路等隐性或突发性故障因传统监测手段存在响应滞后、风险识别精度不足等问题,成为火灾防治的难点。为此,本研究构建面向电气火灾防治的交流线路故障模拟系统,集成短路、过载、接地故障3类典型故障模块,并建立多源信号同步采集与分析平台。试验结果表明,短路故障能量释放呈现显著相位依赖性,电压上升沿短路时释放能量达158.8 J,较电压下降沿工况高249.8%;无漏保接地故障在3 A持续电流下局部迅速升温,存在火灾风险;过载试验揭示了导线线径、电流强度与温升速率间的非线性耦合关系,1.5 mm^(2)导线在56 A过载时温升速率达3.32℃/s,远超2.5 mm^(2)导线同工况表现。基于试验数据并区分保护状态构建火灾风险等级评价体系:在无保护条件下,无漏保接地故障风险高于过载运行;在有保护条件下,短路故障因产生瞬时电弧伴随高能量释放,成为主要火灾隐患,而接地故障则能被漏电保护有效及时切断。研究成果可为火灾预警阈值设定、故障反演分析及火灾物证鉴定提供数据支撑,对提升电气系统主动防火能力具有重要实践价值。 展开更多
关键词 电气火灾 接地故障 过载运行 短路故障 多源信号同步采集
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高过载永磁电机瞬态温度场建模与分析
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作者 史涔溦 娄群健 +2 位作者 颜冬 邱建琪 史婷娜 《电工电能新技术》 北大核心 2026年第1期21-28,共8页
机器人关节电机运行于高过载工况时,绕组端部短时高温升会危害电机绕组绝缘,对永磁电机运行性能及可靠性带来隐患。本文针对一台带有绕组端部环氧灌封结构的永磁电机在高过载工况下的瞬态短时高温升,提出了一种基于集总参数热网络(LPTN... 机器人关节电机运行于高过载工况时,绕组端部短时高温升会危害电机绕组绝缘,对永磁电机运行性能及可靠性带来隐患。本文针对一台带有绕组端部环氧灌封结构的永磁电机在高过载工况下的瞬态短时高温升,提出了一种基于集总参数热网络(LPTN)法的瞬态等效热网络建模方法。该方法考虑了环氧比热容随时间的变化,并计及了各个节点的等效热容,采用有限差分法推导了瞬态温度迭代计算公式。采用所提出的模型及计算方法,针对样机4倍过载短时运行工况,分别计算了自然对流及绕组端部环氧灌封两种冷却方式下的瞬时温升特性,与计算流体力学(CFD)方法的仿真结果进行了对比验证;此外,采用所建立的模型分析了环氧热导率、过载时长占比对温度特性的影响。最终通过样机过载温升实验,证明了所提出瞬态热网络建模方法的合理性和瞬态温度计算方法的准确性。 展开更多
关键词 高过载永磁电机 瞬态等效热网络 环氧树脂灌封 冷却结构
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CAC范式下健康信息过载对个体数字囤积行为的影响机理
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作者 张坤 谷晶晶 +1 位作者 李力 翟运开 《图书馆论坛》 北大核心 2026年第1期126-137,共12页
文章旨在揭示健康信息过载对个体数字囤积行为的影响,以完善数字囤积行为研究理论体系,为用户焦虑情绪纾解、数字囤积行为纠偏等提供理论与实践参考。文章以CAC理论为基本框架,构建健康信息过载对数字囤积行为的影响模型,并借助结构方... 文章旨在揭示健康信息过载对个体数字囤积行为的影响,以完善数字囤积行为研究理论体系,为用户焦虑情绪纾解、数字囤积行为纠偏等提供理论与实践参考。文章以CAC理论为基本框架,构建健康信息过载对数字囤积行为的影响模型,并借助结构方程模型和人工神经网络方法深入分析健康信息过载对个体数字囤积行为的影响机理。研究发现,数字囤积行为表现为个体对健康信息的过度获取和删除困难;健康信息过载情境下的焦虑情绪表现为错失焦虑、信息焦虑和健康焦虑,且健康信息过载对错失焦虑、信息焦虑和健康焦虑具有显著正向影响;情感维度下的错失焦虑对健康焦虑和过度获取、删除困难均有显著正向影响,信息焦虑显著正向影响错失焦虑和健康焦虑,而健康焦虑对过度获取、删除困难也均有显著正向影响。 展开更多
关键词 信息过载 数字囤积 数字行为 焦虑情绪 CAC理论
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铁代谢紊乱对多囊卵巢综合征的影响及中药治疗研究进展
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作者 韩冰 柴美伶 +2 位作者 王昕 李品 陈旭 《中国处方药》 2026年第5期115-120,共6页
多囊卵巢综合征(PCOS)是一种涉及内分泌与代谢功能紊乱的综合性疾病,其发病机制是遗传易感性与环境因素的交互作用,临床以排卵障碍、高雄激素血症及卵巢多囊形态为特征性表现。近年来,铁代谢异常在PCOS病理进程中的作用机制逐渐成为研... 多囊卵巢综合征(PCOS)是一种涉及内分泌与代谢功能紊乱的综合性疾病,其发病机制是遗传易感性与环境因素的交互作用,临床以排卵障碍、高雄激素血症及卵巢多囊形态为特征性表现。近年来,铁代谢异常在PCOS病理进程中的作用机制逐渐成为研究热点,研究表明铁过载可通过诱发胰岛素抵抗、脂代谢异常、高雄激素血症、氧化应激及慢性炎症反应等多重途径参与疾病的发生发展。本文系统梳理铁代谢紊乱与PCOS病理特征间的分子关联机制,并从调节铁稳态角度切入,对中药单体及中药复方在改善PCOS患者内分泌代谢异常方面的潜在作用靶点进行系统总结。通过整合现代药理学研究成果与中医“整体调控”理论优势,为构建基于铁代谢调控的中医药干预PCOS新策略提供理论依据和研究思路。 展开更多
关键词 多囊卵巢综合征 铁代谢 铁过载 中医药治疗 代谢异常
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黄芩素通过激活Keap1/Nrf2/HO-1通路减轻铁过载引起的心肌细胞损伤
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作者 龙兴江 覃娇凤 黄贤贵 《中国临床新医学》 2026年第1期83-90,共8页
目的探讨黄芩素(BAL)对铁过载引起心肌细胞损伤的保护作用机制。方法通过200μmol/L柠檬酸铁(FC)干预心肌细胞H9c224 h构建铁过载细胞模型。分析不同浓度BAL(3、10、30μmol/L)对铁过载的心肌细胞的保护作用,以及抑制Kelch-样ECH相关蛋... 目的探讨黄芩素(BAL)对铁过载引起心肌细胞损伤的保护作用机制。方法通过200μmol/L柠檬酸铁(FC)干预心肌细胞H9c224 h构建铁过载细胞模型。分析不同浓度BAL(3、10、30μmol/L)对铁过载的心肌细胞的保护作用,以及抑制Kelch-样ECH相关蛋白1(Keap1)/核因子E2相关因子2(Nrf2)/血红素加氧酶-1(HO-1)通路(经HO-1抑制剂SnPP或Nrf2抑制剂ML385处理)对BAL保护心肌细胞作用的影响。通过CCK-8法检测细胞活力,通过实时定量聚合酶链反应(RT-qPCR)检测炎症因子肿瘤坏死因子α(TNF-α)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)的表达水平,通过DCFH-DA荧光探针检测活性氧(ROS)水平,采用免疫荧光染色检测4-羟基壬烯醛(4-HNE)表达情况。通过试剂盒检测氧化应激指标丙二醛(MDA)、谷胱甘肽(GSH)表达水平以及铁含量。通过Western blot实验检测Keap1/Nrf2/HO-1通路相关蛋白以及铁死亡相关蛋白表达水平。结果BAL可提高铁过载H9c2细胞的活力,降低炎症因子TNF-α、IL-1β和IL-6以及氧化应激指标ROS、4-HNE的表达水平,使MDA表达水平降低,GSH表达水平升高,干预效果呈剂量依赖性。经BAL干预后,铁过载H9c2细胞铁沉积减少,铁死亡相关蛋白溶质载体家族7成员11(SLC7A11)、谷胱甘肽过氧化物酶4(GPx4)、溶质载体家族3成员2(SLC3A2)蛋白表达升高,环氧化酶2(COX-2)蛋白表达降低。Western blot实验结果显示,BAL激活Keap1/Nrf2/HO-1通路,抑制Keap1蛋白表达,促进Nrf2、HO-1蛋白表达,干预效果呈剂量依赖性。经SnPP或ML385处理后,BAL对铁过载H9c2细胞的保护作用减弱,细胞活力降低,炎症因子表达升高,氧化应激和脂质过氧化增强,铁沉积增多,铁死亡增强。结论BAL可能通过激活Keap1/Nrf2/HO-1通路而减轻铁过载引起的心肌细胞损伤。 展开更多
关键词 黄芩素 铁过载 心肌细胞 氧化应激 Keap1/Nrf2/HO-1通路 铁死亡
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Overloading of Landing Based on the Deformation of the Lunar Lander 被引量:16
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作者 陈金宝 聂宏 +1 位作者 张明 汪岸柳 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第1期43-47,共5页
Along with the progress of sciences and technologies, a lot of explorations are taken in many countries or organizations in succession. Lunar, the natural satellite of the earth, become a focus of the space discovery ... Along with the progress of sciences and technologies, a lot of explorations are taken in many countries or organizations in succession. Lunar, the natural satellite of the earth, become a focus of the space discovery again recently because of its abundant resource and high value in use. Lunar exploration is also one of the most important projects in China. A primary objective of the probe in lunar is to soft-land a manned spacecraft on the lunar surface. The soft-landing system is the key composition of the lunar lander. In the overall design of lunar lander, the analysis of touchdown dynamics during landing stage is an important work. The rigid-flexible coupling dynamics of a system with flexible cantilevers attached to the main lander is analyzed. The equations are derived from the subsystem method. Results show that the deformations of cantilevers have considerable effect on the overloading of the lunar lander system. 展开更多
关键词 lunar lander rigid-flexible coupling DEFORMATION overloadING
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基于微信平台的数字囤积行为对用户信息焦虑的影响机制研究
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作者 陈兰杰 吴兰冰 《四川图书馆学报》 2026年第1期55-64,共10页
文章通过对23名微信用户进行半结构化访谈,运用扎根理论对文本进行编码与分析,构建了数字囤积与信息焦虑间的动态模型,揭示了微信平台中数字囤积行为对用户信息焦虑的影响机制。研究发现,数字囤积行为受风险规避、技术驱动、情感驱动、... 文章通过对23名微信用户进行半结构化访谈,运用扎根理论对文本进行编码与分析,构建了数字囤积与信息焦虑间的动态模型,揭示了微信平台中数字囤积行为对用户信息焦虑的影响机制。研究发现,数字囤积行为受风险规避、技术驱动、情感驱动、认知驱动与任务驱动五大动因驱动,并在短期内可通过“存储即掌控”认知缓解焦虑;长期则因信息过载、功能限制及管理惰性形成“数字迷雾”,反而加剧焦虑。数字囤积行为对焦虑存在双向影响:平台与用户习惯匹配时可带来安全感,失配则强化焦虑。 展开更多
关键词 数字囤积 信息焦虑 信息过载 数字迷雾
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资源保存理论视角下企业绿色人力资源管理对员工绿色行为的双刃剑效应研究
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作者 张喆 张赟 李光亚 《管理工程学报》 北大核心 2026年第1期175-188,共14页
在职场中,激发员工绿色行为对企业响应国家双碳政策、实现碳减排至关重要。绿色人力资源管理日益受到学者与业界关注。企业实施绿色人力资源管理对员工绿色行为有何影响?基于资源保存的理论视角,本文同时关注绿色人力资源管理对员工绿... 在职场中,激发员工绿色行为对企业响应国家双碳政策、实现碳减排至关重要。绿色人力资源管理日益受到学者与业界关注。企业实施绿色人力资源管理对员工绿色行为有何影响?基于资源保存的理论视角,本文同时关注绿色人力资源管理对员工绿色行为的促进作用、潜在的负面影响及其具体机制。基于资源保存理论,本文提出,感知绿色人力资源管理通过员工绿色自我效能感(资源增益路径)和感知角色过载(资源减损路径)两条中介路径对员工绿色行为产生双刃剑式影响,且员工调节定向(提升定向和预防定向)对上述资源增益和减损路径起调节作用。多时段、多来源(领导-员工配对)的实证调研(N=306)支持了本文的研究假设。本文的结论对企业绿色管理实践具有重要启示。 展开更多
关键词 绿色人力资源管理 员工绿色行为 绿色自我效能感 感知角色过载 调节定向
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大质量飞船返回舱竖直着陆缓冲特性研究
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作者 何青松 滕海山 +4 位作者 牟金岗 雷江利 武士轻 竺梅芳 赵淼 《航天器工程》 北大核心 2026年第1期70-78,共9页
为研究大质量(5000~10000 kg)返回舱着陆缓冲特性,文章以我国新一代载人飞船返回舱为研究对象,开展了返回舱竖直着陆缓冲试验,建立了返回舱竖直着陆缓冲理论解析模型,编制了返回舱竖直着陆缓冲特性计算程序,考察了参数变化对返回舱着陆... 为研究大质量(5000~10000 kg)返回舱着陆缓冲特性,文章以我国新一代载人飞船返回舱为研究对象,开展了返回舱竖直着陆缓冲试验,建立了返回舱竖直着陆缓冲理论解析模型,编制了返回舱竖直着陆缓冲特性计算程序,考察了参数变化对返回舱着陆缓冲性能的影响。研究结果表明:排气口面积对返回舱着陆缓冲性能影响十分显著,排气口面积越大,返回舱的缓冲过载峰值越小;气囊初始充气压力越大和气囊初始温度的对着陆缓冲过载影响相对较小,初始充气压力越大,着陆缓冲过载峰值越小,气囊初始温度减小,着陆缓冲过载略微增加;排气过载阈值总体上对返回舱着陆缓冲性能影响较小;返回舱竖直着陆缓冲特性理论模型计算结果与试验结果符合较好,验证了理论模型的可靠性。 展开更多
关键词 返回舱 着陆缓冲 理论解析 缓冲过载
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输血相关循环超负荷临床诊治的专家共识(2026版)
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作者 中国输血协会临床输血学专业委员会《输血相关循环超负荷临床诊治的专家共识(2026版)》编写组 周吉成 +87 位作者 王学锋 谢珏 钱宝华 黄远帅 于洋 于天为 马现君 王娟 王也 王宝燕 王晓刚 王秋实 王海燕 王娅婕 韦海春 尹文 甘佳 付丹晖 白振杰 乐爱平 达珍 刘小信 刘贵年 汤朝晖 安贵鹏 阮钧 苏茜 李倩 李玲 李芳 李慧 李海宏 李尊严 杨莉 吴巨峰 沈长新 张婵 张琦 张晓萍 张光文 陆华 陈伟 陈青 陈静 陈进凡 陈秉宇 陈凤花 林甲进 林陆韬 罗军 周妮嫱 周华友 周树生 庞德 庞洁 郑佳 郑昌成 居敏 赵阳 赵燕 胡芃 胡俊华 查占山 洪强 浑守永 祝丽丽 袁长玲 莫善晓 夏文强 高强 郭晓纲 唐长玖 唐晓峰 黄凯 黄华华 黄维维 曹荣祎 梁敏兰 蓝梅 蔡晓红 谭斌 谭彬宾 樊瑞军 潘健 潘常瑜 燕备战 魏玉萍 魏亚明 《临床输血与检验》 2026年第1期1-8,51,共9页
输血相关循环超负荷(transfusion-associated circulatory overload,TACO)是一种严重的输血并发症。中国输血协会临床输血学专业委员会组织我国包括输血科、血液科、心血管内科、呼吸科及重症医学科等领域的专家学者制订了《输血相关循... 输血相关循环超负荷(transfusion-associated circulatory overload,TACO)是一种严重的输血并发症。中国输血协会临床输血学专业委员会组织我国包括输血科、血液科、心血管内科、呼吸科及重症医学科等领域的专家学者制订了《输血相关循环超负荷临床诊治的专家共识(2026版)》,该共识就TACO相关的辅助检查、诊断与鉴别诊断、预防及治疗策略提出了专家共识意见,以便进一步提高我国TACO的诊治水平。 展开更多
关键词 输血相关循环超负荷 血液成分 肺水肿 呼吸困难
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基于模型完整性与卡尔曼滤波的电缆线路纵联保护原理
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作者 常文豪 张沛超 +2 位作者 季亮 范春菊 刘中平 《电工电能新技术》 北大核心 2026年第2期111-122,共12页
电缆线路广泛用于海上风电并网系统和城市电网中,其分布电容会影响差动保护的性能。为此,本文提出一种基于模型完整性与卡尔曼滤波的电缆线路纵联保护新原理。首先建立电缆线路的T型等效时域分相模型,然后利用卡尔曼滤波器动态递推的特... 电缆线路广泛用于海上风电并网系统和城市电网中,其分布电容会影响差动保护的性能。为此,本文提出一种基于模型完整性与卡尔曼滤波的电缆线路纵联保护新原理。首先建立电缆线路的T型等效时域分相模型,然后利用卡尔曼滤波器动态递推的特点,对线路两端电流和电容电流进行实时状态估计,进而提出基于线路模型完整性的新型保护判据。最后,在PSCAD/EMTDC中搭建110 kV电缆线路模型,并与常规差动保护进行对比验证。结果表明,在区外故障时,本文所提保护原理能准确估计线路电容电流,提高了保护安全性;在区内故障时,保护具有良好速动性和灵敏性,在线路重载情况下能耐受100Ω过渡电阻;对于同步误差、线路参数误差以及采样值异常,本保护原理均有一定抵抗能力。 展开更多
关键词 电缆线路 纵联保护 卡尔曼滤波 状态估计 模型完整性 重载高阻接地故障
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