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黄芩素可缓解蛛网膜下腔出血后神经元的铁死亡

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中国组织工程研究 2025年第1期29卷 52-57页

作者：朱婷岳婷婷崔悦鲁悦李伟杭春华南京中医药大学鼓楼临床医学院江苏省南京市210008 南京大学医学院附属鼓楼医院神经外科江苏省南京市210008

背景:铁死亡是一种区别于凋亡、坏死等新型细胞程序性死亡的方式,主要由累积的脂质过氧化引起,已被证实参与蛛网膜下腔出血后的病理过程。黄芩素是一种铁螯合剂,能够抑制脂质过氧化反应,但其在蛛网膜下腔出血后早期脑损伤中缓解神经元... 详细信息

背景:铁死亡是一种区别于凋亡、坏死等新型细胞程序性死亡的方式,主要由累积的脂质过氧化引起,已被证实参与蛛网膜下腔出血后的病理过程。黄芩素是一种铁螯合剂,能够抑制脂质过氧化反应,但其在蛛网膜下腔出血后早期脑损伤中缓解神经元铁死亡的作用仍未明确。目的:探讨黄芩素治疗蛛网膜下腔出血后对神经元铁死亡的影响及机制。方法:提取孕16-17 d C57BL/6L胎鼠大脑皮质神经元细胞,运用血红蛋白刺激原代神经元模拟体外蛛网膜下腔出血模型。采用CCK-8法检测5,15,25,50,100μmol/L黄芩素作用24 h后原代神经元细胞的活力,确定黄芩素的最适浓度。然后将原代神经元细胞分为对照组、血红蛋白组、血红蛋白+黄芩素组,利用试剂盒检测细胞内活性氧和丙二醛水平,RT-PCR检测铁死亡相关标记物PTGS2、SLC7A11、谷胱甘肽过氧化物酶4的mRNA表达;进一步将原代神经元细胞分为对照组、SLC7A11抑制剂Erastin组、血红蛋白组、血红蛋白+黄芩素组、血红蛋白+黄芩素+Erastin组,Western blot检测铁死亡相关标记物SLC7A11和谷胱甘肽过氧化物酶4的蛋白表达。结果与结论:(1)选取25μmol/L黄芩素作为后续实验浓度;(2)与血红蛋白组相比,血红蛋白+黄芩素组丙二醛和活性氧水平显著下降(P <0.05);(3)与血红蛋白组相比,血红蛋白+黄芩素组PTGS2的m RNA表达显著下降,SLC7A11和谷胱甘肽过氧化物酶4的m RNA表达显著升高(P <0.000 1);(4)SLC7A11抑制剂Erastin能在一定程度上逆转黄芩素改善的铁死亡作用(P <0.05);(5)结果表明,黄芩素可通过SLC7A11/GPX4通路缓解蛛网膜下腔出血后神经元细胞的铁死亡。

关键词：蛛网膜下腔出血黄芩素铁死亡神经元 Erastin 小鼠

Advance in the understanding of vasovagal syncope in children and adolescents

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World Journal of Pediatrics 2021年第1期17卷 58-62页

作者： Hong-Xia li Lu Gao yue yuan Department of Cardiology National Center for Children's HealthBeijing Children's HospitalCapital Medical UniversityBeijingChina

Background Vasovagal syncope(VVS)accounts for 60-80% of cases of neurally mediated *** results from acute orthostatic intolerance and recurrent syncopal attacks,which can seriously affect an individual's quality of *** addition,some children even experience trauma during ***,it is particularly important to clarify the pathogenesis of *** aim of our study is to reveal the latest research progress of *** sources literature that involved the pathogenesis of VVS were selected from Cochrane library(1990-2019),EMBASE(1991-2019)and PubMed(1968-2019)*** Hypovolemia,autonomic dysfunction,vasomotor dysfunction,baroreceptor reflex abnormalities,endothelial dys-function,serotonin surges,and gut microbiota were involved in the underlying mechanism of *** VVS is not always a benign *** aspects were involved in its ***-Jarish reflex,dysfunction of the autonomic nervous system,genetic factors and so on played important roles in VVS;however,the mecha-nism remains unclear.

关键词： Autonomic nervous system Bezold-Jarish reflex Children Genetic pathogenesis Vasovagal syncope

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent from sewage treatment plant

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 299-310页

作者： Xinshu liu Xiaoman Su Sijie Tian yue li Rongfang yuan Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Department of Environmental Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment ***(O_(3))is often used in water *** study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of *** changes in NOM components during ozonation were also *** was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and *** hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the *** mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation *** NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct *** dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like *** study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.

关键词： Sulfamethoxazole Ozonation Natural organic matters Secondary effluent Degradation mechanism

Adaptive security control of time-varying constraints nonlinear cyber-physical systems with false data injection attacks

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Journal of Control and Decision 2024年第1期11卷 50-59页

作者： yue-Ming Wang yuan-Xin li Department of Science Liaoning University of TechnologyJinzhouPeople’s Republic of China

In this article,an adaptive security control scheme is presented for cyber-physical systems(CPSs)suffering from false data injection(FDI)attacks and time-varying state ***,an adaptive bound estimation mechanism is introduced in the backstepping control design to mitigate the effect of FDI ***,to solve the unknown sign time-varying statefeedback gains aroused by the FDI attacks,a type of Nussbaum function is employed in the adaptive security ***,by constructing a barrier Lyapunov function,it can be ensured that all signals of controlled system are bounded and the time-varying state constraints are not ***,the provided simulation examples demonstrate the effectiveness of the proposed controller.

关键词： Neural networks backstepping technology false data injection(FDI)attacks nonlinear cyber-physical systems controls

一种近红外光谱定量分析软件预测性能评价方法

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光谱学与光谱分析 2025年第1期45卷 213-221页

作者：李蓉郝璐袁洪福何桂梅邓天龙杜彪龚丽岳欣天津科技大学海洋与环境学院天津300457 天津市滨海新区环境创新研究院天津300457 中国环境科学研究院北京100012 北京易兴元石化技有限公司北京101300 中国石油大学(北京) 北京102249

常用的多元分析模型评价指标尚缺乏评价近红外分析软件多项重要预测性能指标的能力,成为近红外光谱仪预测性能以及实际近红外应用中模型适用性评价的痛点。为此,旨在发展一种近红外定量分析软件预测性能的评价方法。以近红外测定汽油烯... 详细信息

常用的多元分析模型评价指标尚缺乏评价近红外分析软件多项重要预测性能指标的能力,成为近红外光谱仪预测性能以及实际近红外应用中模型适用性评价的痛点。为此,旨在发展一种近红外定量分析软件预测性能的评价方法。以近红外测定汽油烯烃浓度为研究对象,收集了192个国Ⅵ汽油样品,包括92#、95#和98#;采集其近红外光谱;按照GB/T 30519-2014测定其烯烃浓度作为参考值,分别使用两种不同的多元分析软件(1种是偏最小二乘(PLS)建模软件,另1种是非PLS的软件),建立了两个校正模型。研究发现,与参考值相比,PLS模型对低浓度样品预测值呈正偏差,高浓度的呈负偏差,即“均值化”现象。常用的模型预测性能评价指标尚不能评价模型预测值的均值化程度,也不能评价:(1)预测值与参考值偏差大于参考方法再现性的样本占比,(2)模型泛化能力。本文针对上述问题,提出了4项新评价指标包括均值化指数(AE)、预测偏差超限值样本占比(Ratio)、异常样本预测偏差(DAS)和孤立样品预测偏差(DIS)。综合常用的评价指标和新评价指标(共12项),对仪器选型的近红外光谱定量分析软件预测性能的评价、实际近红外分析应用中模型适用性的评价均具有实际意义,对近红外分析学术研究也具参考意义。

关键词：近红外光谱多元分析模型评价近红外分析软件评价汽油烯烃浓度

Supporting multi-user real-time VBR video service using dynamic bandwidth management based on prediction

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 64-71页

作者： XU Zhi-yuan li Hui LU yue-ming JI yue-feng Key Laboratory of Optical Communications and lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia ***,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic *** support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management *** scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management *** addition,to support multi-user application,an adjustment priorities classified strategy is also put ***,a test-bed based on this management scheme is *** experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.

关键词： dynamic bandwidth management MDI QoS real-time time-domain adaptive linear predictor VBR video

3D stress simulation and parameter design during twin-roll casting of 304 stainless steel based on the Anand model

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 666-673页

作者： Jing Guo yuan-yuan liu li-gang liu yue Zhang Qing-xiang Yang State Key Laboratory of Metastable Materials Science & Technology Yanshan University Nanjing Iron & Steel Co. School of Material Science and Engineering University of Science and Technology Beijing

This study first investigated cracks on the surface of an actual steel strip. Formulating the Anand model in ANSYS software, we then simulated the stress field in the molten pool of type 304 stainless steel during the twin-roll casting process. Parameters affecting the stress distribution in the molten pool were analyzed in detail and optimized. After twin-roll casting, a large number of transgranular and intergranular cracks resided on the surface of the thin steel strip, and followed a tortuous path. In the molten pool, stress was enhanced at the exit and at the roller contact positions. The stress at the exit decreased with increasing casting speed and pouring temperature. To ensure high quality of the fabricated strips, the casting speed and pouring temperature should be controlled above 0.7 m/s and 1520℃, respectively.

关键词： stainless steel strip metal roll casting stress surface cracks numerical analysis

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin yuan Weicheng Kong Pengcheng Xia yuanrong li yuewei Chen Nian liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

A simple and convenient method for the synthesis of S-aryl phosphorothioates catalyzed by cesium hydroxide

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Chinese Chemical Letters 2013年第12期24卷 1103-1105页

作者： yue-Jun Ouyang yuan-yuan li Ning-Bo li Xin-Hua Xu Department of Chemistry and Chemical Engineering Huaihua University College of Chemistry and Chemical Engineering Hunan University

In the presence of a catalytic amount of cesium hydroxide, the corresponding S-aryl phosphorothioates can he obtained by the reactions of dialkyl phosphites with diaryldisulfides in excellent yields at room temperature, using DMSO as a solvent. The reaction mechanism was discussed. The method provides a new and expedient path for the preparation of $-aryl phosphorothioates.

关键词： Cesium hydroxide Diaryldisulfides O O-Dialkyl-S-arylphosphorothioates