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China Geology 2024年第1期7卷 1-11页

作者： Chang li Fu Wang Peng Yang Fei-cui Wang Yun-zhuang Hu Yan-lin Zhao li-zhu Tian Rui-bin Zhao Tianjin Center(North China Center of Geoscience Innovation) China Geological Survey(CGS)Tianjin 300170China Tangshan Hydrological Survey and Research Center of Heibei Province Tangshan063000China Key Laboratory of Coast Geo-Environment China Geological SurveyCGSTianjin 300170China Tianjin Key Laboratory of Coast Geological Processes and Environmental Safety Tianjin 300170China

This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s *** interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software ***,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST *** show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and *** total carbon storage is assessed at 2.11×10^(6) t,with specific regional data *** since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in *** important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove *** study is poised to guide future mangroverelated investigations and conservation strategies.

关键词： Mangrove Wetland Carbon storage Ecological conservation ArcGIS software platform Restoration InVEST model Quantitative analysis Coastal zone of China

当归芍药散治疗非酒精性脂肪性肝病作用机制研究现状

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中医药临床杂志 2024年第5期36卷 982-986页

作者：陈旭李秀园李爽陈婕天津中医药大学天津301617 天津中医药大学第二附属医院天津300250

随着人们生活水平的提高和饮食习惯的改变,非酒精性脂肪性肝病(NAFLD)逐渐成为世界上最常见的慢性肝病之一。其发病率呈逐年上升的趋势,因其发病机制较为复杂,尚不明确,目前未有特效的治疗药物,因此,寻找安全、高效、经济的NAFLD治疗药... 详细信息

随着人们生活水平的提高和饮食习惯的改变,非酒精性脂肪性肝病(NAFLD)逐渐成为世界上最常见的慢性肝病之一。其发病率呈逐年上升的趋势,因其发病机制较为复杂,尚不明确,目前未有特效的治疗药物,因此,寻找安全、高效、经济的NAFLD治疗药物迫在眉睫。与具有快速降脂作用的西药相比,中药因其具有多靶点、多通道作用机制等独特优势,在NAFLD的治疗中越来越受到关注。NAFLD的中医病机为肝脾失调、痰瘀互结。当归芍药散源于《金匮要略》,具有调和肝脾、祛湿消痰、活血化瘀之效,与该病病机相契合。当归芍药散已被证明通过调节各种途径来治疗NAFLD,包括改善肠道菌群、抗氧化应激、调节肠肝轴、减轻炎症反应等。中药因其具有多靶点、多通道作用机制对治疗NAFLD有独特优势,而当归芍药散药物组成多样,药理作用复杂,难以了解调控NAFLD的具体机制,目前缺少当归芍药散的临床试验研究,组成药物的剂量与配比问题无明确规定,当归芍药散诱导的肝毒性和肾毒性也需进一步探讨。因此,文章通过检索与整理相关文献,对当归芍药散治疗NAFLD的作用机制和实验数据及临床研究结果进行归纳和分析,总结了当归芍药散治疗NAFLD的优势与不足,为今后中医药进一步开展包括当归芍药散在内的深入实验研究及后续临床运用和推广提供思路和展望。

关键词：当归芍药散非酒精性脂肪性肝病作用机制研究现状

Luminescent metal-halide perovskites:fundamentals,synthesis,and light-emitting devices

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Science China Chemistry 2024年第6期67卷 1776-1838页

作者： Kang Wang Jeong Hui Kim Jie Yang Xiaoke liu Yixuan Dou Yuxuan li Weijian Tao Haiyun Dong Haiming Zhu Kaifeng Wu li Na Quan Feng Gao Jianpu Wang Letian Dou Yong Sheng Zhao Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China Davidson School of Chemical Engineering Purdue UniversityWest LafayetteIN47907USA School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)&School of Flexible Electronics(Future Technologies)Nanjing Tech University(NanjingTech)Nanjing211816China department of Physics Linköping UniversityLinköping58183Sweden department of Chemistry Virginia TechBlacksburgVA24060USA State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China department of Chemistry Zhejiang UniversityHangzhou310058China Changzhou University Changzhou213164China department of Chemistry Purdue UniversityWest LafayetteIN47907USA

Metal-halide perovskites have garnered considerable research attention as highly efficient light emitters in recent years due to their outstanding optoelectronic properties with remarkable tunability and excellent solution *** advancements have been achieved in the development of novel halide perovskites,and the exploitations of these materials in lightemitting *** review comprehensively outlines recent breakthroughs in metal-halide perovskites,encompassing the rational design of perovskite materials with tunable light emission properties,the controllable growth of single crystal for a deeper understanding of their structure-property relationships,as well as the fundamental insights into the photophysics and carrier dynamics in perovskite ***,it provides an overview of recent applications of perovskite materials in high-performance light-emitting diodes(LEDs)and lasers.

关键词： metal-halide perovskites perovskite luminescent materials perovskite synthesis excited-state processes perovskite light-emitting diodes perovskite lasers

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Subtraction of liposome signals in cryo-EM structural determination of protein-liposome complexes

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Chinese Physics B 2024年第8期33卷 569-577页

作者：李首卿李明王玉梅李雪明 Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Protein Sciences of Ministry of Education School of Life SciencesTsinghua UniversityBeijing 100084China State Key Laboratory of Membrane Biology School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua–Peking Joint Center for life Sciences Beijing 100084China Beijing Frontier Research Center for Biological Structure Beijing 100084China School of life Sciences Tsinghua UniversityBeijing 100084China Beijing Branch of Songshan Lake Materials Laboratory Beijing 100190China

Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong signal of liposomes under cryo-EM imaging conditions often interferes with the structural determination of the embedded membrane ***,we propose a liposome signal subtraction method based on single-particle two-dimensional(2D)classification average images,aimed at enhancing the reconstruction resolution of membrane *** analyzed the signal distribution characteristics of liposomes and proteins within the 2D classification average images of protein–liposome complexes in the frequency *** on this analysis,we designed a method to subtract the liposome signals from the original particle *** the subtraction,the accuracy of single-particle three-dimensional(3D)alignment was improved,enhancing the resolution of the final 3D *** demonstrated this method using a PIEZO1-proteoliposome dataset by improving the resolution of the PIEZO1 protein.

关键词： cryo-EM protein–liposome complexes liposome signal subtraction 2D classification averaging

Fracture propagation and evolution law of indirect fracturing in the roof of broken soft coal seams

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International Journal of Coal Science & Technology 2024年第1期11卷 78-102页

作者： Haifeng Zhao Pengyue li Xuejiao li Wenjie Yao College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China Oil and Gas Exploration Company Shanxi Yanchang Petroleum(Group)Co.LTDYan’an716000China

Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible *** this work,the No.5 coal seam in the Hancheng block was taken as the research *** on the findings of true triaxial hydraulic fracturing experiments and field pilot under this technology and the cohesive element method,a 3D numerical model of indirect fracturing in the roof of broken soft coal seams was established,the fracture morphology propagation and evolution law under different conditions was investigated,and analysis of main controlling factors of fracture parameters was conducted with the combination weight method,which was based on grey incidence,analytic hierarchy process and entropy weight *** results show that“士”-shaped fractures,T-shaped fractures,cross fractures,H-shaped fractures,and“干”-shaped fractures dominated by horizontal fractures were *** parameter combinations can form different fracture *** the coal seam permeability is lower and the minimum horizontal principal stress difference between layers and fracturing fluid injection rate are both larger,it tends to form“士”-shaped *** the coal seam permeability and minimum horizontal principal stress between layers and perforation position are moderate,cross fractures are easily *** fracture parameters have different main controlling *** factors of perforation location,fracturing fluid injection rate and viscosity are the dominant factors of hydraulic fracture shape *** study can provide a reference for the design of indirect fracturing in the roof of broken soft coal seams.

关键词： Indirect fracturing Roof of coal seam Fracture propagation and evolution Coalbed methane Cohesive element method Combination weight method

Type Synthesis of Fully decoupled Three Translational Parallel Mechanism with Closed-Loop Units and High Stifness

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 231-247页

作者： Shihua li Sen Wang Haoran li Yongjie Wang shuang Chen Hebei Provincial Key Laboratory of Parallel Robot and Mechatronic Systems Yanshan UniversityQinhuangdao 066004China

In order to solve the problem of weak stifness of the existing fully decoupled parallel mechanism, a new synthesis method of fully decoupled three translational (3T) parallel mechanisms (PMs) with closed-loop units and high stifness is proposed based on screw theory. Firstly, a new criterion for the full decoupled of PMs is presented that the reciprocal product of the transmission wrench screw matrix and the output twist screw matrix of PMs is a diagonal matrix, and all elements on the main diagonal are nonzero constants. The forms of the transmission wrench screws are determined by the criterion. Secondly, the forms of the actuated and unactuated screws can be obtained according to their relationships with the transmission wrench screws. The basic decoupled limbs are generated by combination of the above actuated and unactuated screws. Finally, a closed-loop units construction method is investigated to apply the decoupled mechanisms in a better way on the high stifness occasion. The closed-loop units are constructed in the basic decoupled limbs to generate a high-stifness fully decoupled 3T PM. Kinematic and stifness analyses show that the Jacobian matrix is a diagonal matrix, and the stifness is obviously higher than that of the coupling mechanisms, which verifes the correctness of the proposed synthesis method. The mechanism synthesized by this method has a good application prospect in vehicle durability test platform.

关键词： Screw theory Three translational parallel mechanism Full decoupled Closed-loop units High stifness

人参皂苷Re与5种环糊精主客体包合过程研究

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中成药 2024年第1期46卷 60-64页

作者：王伟赵鸿双吴天元李铮陆勃帆李慧吴巍长春中医药大学吉林省人参科学研究院吉林长春130117

目的考察人参皂苷Re与阿尔法环糊精、贝塔环糊精、伽马环糊精、羟丙基贝塔环糊精、羟丙基伽马环糊精的主客体包合过程。方法下载5种环糊精结构,采用双层ONIOM[B3LYP/6-31G(d):PM3]方法模拟包合过程,Materials studio软件进行分子动力学... 详细信息

目的考察人参皂苷Re与阿尔法环糊精、贝塔环糊精、伽马环糊精、羟丙基贝塔环糊精、羟丙基伽马环糊精的主客体包合过程。方法下载5种环糊精结构,采用双层ONIOM[B3LYP/6-31G(d):PM3]方法模拟包合过程,Materials studio软件进行分子动力学模拟(MD),分析分子间作用力,饱和水溶液法测定人参皂苷Re溶解度。结果不同环糊精均可与人参皂苷Re自发反应生成包合物,最优构象均为从环糊精的大口端伸向小口端。人参皂苷Re能贯穿于贝塔环糊精、伽马环糊精空腔中,而其他3种环糊精只能将该成分部分包合,并且包合过程均为自发的吸热反应,包合能力依次为伽马环糊精>贝塔环糊精>羟丙基伽马环糊精>羟丙基贝塔环糊精>阿尔法环糊精。范德华力是主要驱动力,大于氢键与疏水作用力。人参皂苷Re在37℃下的溶解度高于25℃下,伽马环糊精对该成分溶解性最强,可增加至9.59~11.18倍。结论伽马环糊精是人参皂苷Re最理想的包合材料。本实验明确了主客体分子的包合分子机制,能为该类超分子药物的定量构效关系探讨提供理论依据与实验参考。

关键词：人参皂苷Re 环糊精主客体包合过程

High-performance piezoresistive sensors based on transfer-free large-area PdSe_(2) films for human motion and health care monitoring

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InfoMat 2024年第1期6卷 139-149页

作者： Rui Zhang Jie lin Tao He Jiafang Wu Zhuojun Yang liwen liu Shaofeng Wen Yimin Gong Haifeng Lv Jing Zhang Yi Yin Fangjia li Changyong Lan Chun li State Key Laboratory of Electronic Thin Films and Integrated devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengduthe People's Republic of China School of Physics University of Electronic Science and Technology of ChinaChengduthe People's Republic of China Sichuan Academy of Medical Sciences and Sichuan People's Hospital Chengduthe People's Republic of China School of Medicine University of Electronic Science and Technology of ChinaChengduthe People's Republic of China

Two-dimensional transition metal dichalcogenides(TMDs)are needed in highperformance piezoresistive sensors due to their strong strain-induced bandgap modification and thereby large gauge ***,integrating a conventional high-temperature chemical vapor deposition(CVD)-grown TMD with a flexible substrate necessitates a transfer process that inevitably degrades the sensing properties of the TMDs and increases the overall fabrication *** present a high-performance piezoresistive strain sensor that employs largearea PdSe_(2) films grown directly on polyimide(PI)substrates via plasma-assisted selenization of a sputtered Pd *** reliable strain transfer from the substrate to the PdSe_(2) film ensures an outstanding strain-sensing capability of the ***,the sensors have a gauge factor of up to315±2.1,a response time under 25 ms,a detection limit of 8×10^(-6),and an exceptional stability of over 104 loadingunloading *** attaching the sensors to the skin surface,we demonstrate their application for measuring physiological parameters in health care monitoring,including motion,voice,and arterial pulse ***,using the PdSe_(2) film sensor combined with deep learning technology,we achieved intelligent recognition of artery temperature from arterial pulse signals with only a 2%difference between predicted and actual *** excellent sensing performance,together with the advantages of low-temperature fabrication and simple device structure,make the PdSe_(2) film sensor promising for wearable electronics and health care sensing systems.

关键词： layered crystal PdSe_(2) piezoresistive effect strain sensor

多胎妊娠减胎术临床特征及妊娠结局分析——历时12年的队列研究

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中华生殖与避孕杂志 2024年第8期44卷 784-790页

作者：李莉李妍仪杨蕊范蒙洁杨硕李嘉宋颖潘宁宁田甜马彩虹李蓉刘平乔杰北京大学第三医院妇产科生殖医学中心女性生育力促进全国重点实验室国家妇产疾病临床医学研究中心(北京大学第三医院)辅助生殖教育部重点实验室(北京大学)生殖内分泌与辅助生殖技术北京市重点实验室北京

目的分析多胎妊娠减胎术患者的妊娠结局及影响活产的因素, 为减胎策略提供参考依据。方法回顾性队列研究纳入2009年1月1日至2020年12月31日期间于北京大学第三医院妇产科生殖医学中心进行多绒毛膜性多胎妊娠减胎术的患者, 分析患者临床... 详细信息

目的分析多胎妊娠减胎术患者的妊娠结局及影响活产的因素, 为减胎策略提供参考依据。方法回顾性队列研究纳入2009年1月1日至2020年12月31日期间于北京大学第三医院妇产科生殖医学中心进行多绒毛膜性多胎妊娠减胎术的患者, 分析患者临床特征, 随访妊娠结局, 分为活产组(n=1 555)和非活产组(n=205), 并应用多因素logistic回归分析影响活产的因素。并进一步亚组分析, 将多胎妊娠分为双绒毛膜双羊膜囊、三胎妊娠、四胎及以上多胎妊娠三组。结果纳入1 925例多胎妊娠减胎病例, 完成妊娠结局随访1 760例。数据显示12年来减胎多胎类型中双绒毛膜双羊膜囊增多, 经腹减胎比例逐年增加, 年减胎患者活产率波动于83%～94%。四胎及以上多胎妊娠减胎后活产率[75.8%(72/95)]分别低于双绒毛膜双羊膜囊减胎后[90.0%(796/884), P<0.001]、双绒毛膜三羊膜囊减胎后[89.9%(241/268), P<0.001]和三绒毛膜三羊膜囊减胎后[86.9%(446/513), P=0.005]。经腹部超声引导下减胎术后活产率[91.4%(655/717)]分别高于经阴道氯化钾(KCl)胎心搏动区注射减胎后活产率[84.9%(304/358), P=0.001]及经阴道胚胎抽吸减胎后活产率[87.0%(596/685), P=0.009], 经阴道KCl胎心搏动区注射减胎与经阴道抽吸减胎活产率差异无统计学意义(P=0.351)。减胎术后保留单胎的患者活产率[89.7%(1 062/1 184)]高于保留双胎患者[85.6%(493/576), P=0.012]。在调整了年龄、助孕方式、多胎类型、保留胚胎数等混杂因素后, 中孕期经腹部超声引导下减胎为活产率的保护因素(P=0.040, OR=1.604, 95%CI:1.021～2.519)。结论随移植策略的改变, 双绒毛膜双羊膜囊妊娠减胎比例增加, 中孕期经腹部超声引导下减胎术的比例增加, 经腹部减胎可能是多胎妊娠减胎术更好的选择;早孕期经阴道抽吸减胎法与KCl胎心搏动区注射法减胎妊娠结局相似;四胎及以上多胎妊娠减胎后妊娠结局较差, 临床上需严格控制胚胎移植数目, 规范诱导排卵方案。

关键词：多胎妊娠多胎妊娠减胎术经阴道多胎妊娠减胎术经腹部多胎妊娠减胎术妊娠结局

加味逍遥散通过肝癌外泌体影响神经细胞突起的研究

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时珍国医国药 2024年第3期35卷 597-601页

作者：黎如霜刘晓明李妞妞秦秋云夏猛广西中医药大学基础医学院广西南宁530200

目的探讨加味逍遥散是否通过外泌体对神经细胞突起的发育发挥调节影响作用。方法采用体外神经细胞、星形胶质细胞非接触式共培养系统模拟体内中枢系统神经细胞和星形胶质细胞相互交错,相互影响的联系,后加入肝癌细胞来源外泌体、经加... 详细信息

目的探讨加味逍遥散是否通过外泌体对神经细胞突起的发育发挥调节影响作用。方法采用体外神经细胞、星形胶质细胞非接触式共培养系统模拟体内中枢系统神经细胞和星形胶质细胞相互交错,相互影响的联系,后加入肝癌细胞来源外泌体、经加味逍遥散含药血清干预后的肝癌细胞来源外泌体,通过比较二者对神经细胞-星形胶质细胞共培养系统中神经细胞树突的长度、分支,兴奋性突触及相关突触蛋白的数量等的影响。结果经肝癌细胞来源外泌体干预的神经细胞树突的长度、分支,兴奋性突触及相关突触蛋白的数量均较空白组减少,而经过加味逍遥散含药血清干预后的肝癌细胞外泌体可显著增加共培养系统中神经细胞的树突长度、分支,兴奋性突触及相关突触蛋白的数量。结论加味逍遥散对肝癌来源外泌体造成的神经细胞突起的异常损伤具有修复和保护作用,即加味逍遥散可能通过外泌体途径干预和修复受损的神经细胞。

关键词：加味逍遥散肝癌来源外泌体神经细胞突起