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北京十三陵中元古代串岭沟期地质事件的探索

地质论评 2000年第4期46卷 400-406页

作者：宋天锐和政军丁孝忠张巧大中国地质科学院地质研究所北京100037

宏观、微观和地球化学研究结果证明在北京十三陵中元古界长城系串沟组有地质事件层。宏观标志包括一系列地震滑塌、砂体液化、层内错断和角砾化构造等;微观标志包括火山晶屑、火山玻璃的假像、显微层内错位等。地球化学资料表明,Re、Os... 详细信息

宏观、微观和地球化学研究结果证明在北京十三陵中元古界长城系串沟组有地质事件层。宏观标志包括一系列地震滑塌、砂体液化、层内错断和角砾化构造等;微观标志包括火山晶屑、火山玻璃的假像、显微层内错位等。地球化学资料表明,Re、Os及其同位素和Ir含量异常,某些稀有元素含量的对比等等,都有可能说明地质事件引起了异常现象的出现。笔者认为串岭沟组的地质事件是由于燕山裂陷槽形成早期的火山活动及由其引发的地震事件产生的。根据北京十三陵串岭沟组地质事件记录的研究,对比蓟县、宽城和曲阳等地的剖面后,笔者认为十三陵地区的串岭沟组相当于蓟县串岭沟组的上部层位。此外,串岭沟组出现火山—地震事件可能导致常州沟组后生动物遗迹化石的延续性被破坏;串岭沟组和常州沟组泥岩中有可能存在自生独居石,自生独居石为U,Th-Pb法同位素测年提供可能。

关键词：地质事件元古界串岭沟组北京十三陵

北京十三陵元古宙大红峪组含事件信息的沉积岩研究

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岩石矿物学杂志 2000年第4期19卷 323-332页

作者：宋天锐和政军丁孝忠张巧大中国地质科学院地质研究所北京100037

北京十三陵元古宙大红峪组在不足 4km的距离内岩相急剧变化 ,实为国内外罕见。从东至西 ,泰陵剖面由灰色角砾硅化岩 +黑色粉砂凝灰页岩 +黄色含长石石英砂岩组成 ,山顶剖面由不纯砂岩 +泥质白云岩组成 ,德胜口剖面由泥质白云岩 +石英砂... 详细信息

北京十三陵元古宙大红峪组在不足 4km的距离内岩相急剧变化 ,实为国内外罕见。从东至西 ,泰陵剖面由灰色角砾硅化岩 +黑色粉砂凝灰页岩 +黄色含长石石英砂岩组成 ,山顶剖面由不纯砂岩 +泥质白云岩组成 ,德胜口剖面由泥质白云岩 +石英砂岩 +层凝灰岩组成。本文仅对泰陵剖面大红峪组的三种岩石进行系统研究。宏观、微观特征、地球化学和同位素地球化学分析数据表明 :泰陵剖面大红峪组的灰色角砾硅化岩和黑色粉砂凝灰页岩是受火山 -地震事件影响形成的沉积岩 ,而覆盖其上的黄色含长石石英砂岩形成于正常滨海环境中。最后提出大红峪组含事件信息的沉积岩形成模式图。

关键词：元古宙大红峪组事件信息地球化学沉积岩

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车载低温绝热气瓶结构强度和振动疲劳分析

低温与超导 2024年第6期52卷 58-64,102页

作者：郝朝阳丁华李沐泽陶昶景罗晓钟刘宏伟江苏大学汽车与交通工程学院镇江212013 张家港中集圣达因低温装备有限公司张家港215600

以车载低温绝热气瓶为研究对象,液氢为低温介质,在气瓶安全层面,探讨了制动过程中液体晃动与结构耦合产生的附加动压对气瓶结构影响,考虑温度的情况下,采用应力线性化准则对气瓶关键部位进行了强度评估。在可靠性层面,分析了气瓶在行驶... 详细信息

以车载低温绝热气瓶为研究对象,液氢为低温介质,在气瓶安全层面,探讨了制动过程中液体晃动与结构耦合产生的附加动压对气瓶结构影响,考虑温度的情况下,采用应力线性化准则对气瓶关键部位进行了强度评估。在可靠性层面,分析了气瓶在行驶过程中路面激励下的共振和振动疲劳失效问题。研究表明:制动减速度和液体对内筒体壁面冲击力呈正相关,且在充装率为70%时,液体晃动对内筒体壁面冲击力达到峰值;在热应力影响下气瓶变形增加97%,最大应力增加19%;气瓶在空载下固有频率大于40 Hz,在考虑低温介质和预应力时,气瓶固有频率低于国标允许的40 Hz;振动疲劳易发生在前后支撑处,高于国家标准646 020次,车载低温绝热气瓶在满载时强度和疲劳满足要求。

关键词：低温绝热气瓶应力分析振动疲劳数值模拟

定制式解剖接骨板系统固定Vancouver BⅠ型股骨假体周围骨折的生物力学分析

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中国组织工程研究 2024年第24期28卷 3807-3813页

作者：王佳琦罗晓中童祎鲁晓波石维祥周欣吴刚丁勇张才东自贡市第四人民医院骨科中心关节与创伤外科四川省自贡市643000 西南医科大学附属医院骨与关节外科四川省泸州市646000

背景:目前锁定接骨板结合钢丝或钢缆治疗股骨假体周围骨折时近端常采用单皮质固定,稳定性不强,且接骨板近端与股骨无法达到解剖贴合,而定制式解剖接骨板系统(customized anatomical plate system,CAPS)可有效解决这一问题。目的:探讨CAP... 详细信息

背景:目前锁定接骨板结合钢丝或钢缆治疗股骨假体周围骨折时近端常采用单皮质固定,稳定性不强,且接骨板近端与股骨无法达到解剖贴合,而定制式解剖接骨板系统(customized anatomical plate system,CAPS)可有效解决这一问题。目的:探讨CAPS固定Vancouver BⅠ型股骨假体周围骨折的生物力学强度。方法:选取1006例股骨CT薄层扫描数据导入MIMICS 21.0版本软件中建立股骨三维重建模型,设为股骨三维重建组;选取56根完整的人体股骨标本设为股骨标本组,两组进行股骨解剖外形测量并进行结果比较,两组结果无明显差异则根据测量结果在MIMICS 21.0软件和NX11.0软件中设计CAPS大致外形;选取8对冰冻人体股骨制作Vancouver BⅠ型股骨假体周围骨折模型,双源CT薄层扫描左侧8根股骨假体周围骨折模型获取数据,将数据传入上述设计软件确定CAPS模型,再依托器械公司最终制作8套CAPS;8对骨折模型编号1-8,左侧采用CAPS固定(CAPS组),右侧采用金属锁定接骨板系统-大型锁定板固定(爪钢板组),L1-L4、R1-R4行垂直加载测试和垂直短周期加载测试,L5-L8、R5-R8行四点弯曲测试和水平短周期加载测试。垂直加载测试和四点弯曲测试收集弯曲载荷、弯曲位移、弯曲应变,采用2种短周期测试收集应变位移,比较2种接骨板的最大载荷、最大位移、抗弯刚度及短周期抗移位能力。结果与结论:①股骨三维重建组与股骨标本组各长度及角度指标比较,差异均无显著性意义(P>0.05),可依据测量结果结合软件设计个体化CAPS;②垂直加载测试中,CAPS组比爪钢板组可承受的最大载荷高(P=0.015)、出现最大弯曲位移小(P=0.014)、抗弯刚度高(P=0.005);③四点弯曲测试中,CAPS组比爪钢板组可承受的最大载荷高(P=0.023)、抗弯刚度高(P=0.005),弯曲位移差异不显著(P=0.216>0.05);④垂直短周期加载测试中CAPS组平均弯曲位移(0.23±0.10)mm显著小于爪钢板组(0.44±0.02)mm(P0.05);⑥提示CAPS具有个体化解剖性,固定Vancouver BⅠ型股骨假体周围骨折更稳固,对临床治疗有一定的指导意义。

关键词：股骨假体周围骨折定制式解剖接骨板系统生物力学股骨解剖形态 Vancouver分型

Digital and global lithologic mapping of the Moon at a 1:2,500,000 scale

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Science Bulletin 2022年第20期67卷 2050-2054,M0003页

作者： Jian Chen Zongcheng Ling Jianzhong Liu Shengbo Chen xiaozhong ding Jianping Chen Weiming Cheng Bo Li Jiang Zhang Lingzhi Sun Changqing Liu Haijun Cao Xiangyu Bi Li Liu Sheng Wan Xiaobin Qi Zixu Zhao Dijun Guo Jinzhu Ji Jingwen Liu Juntao Wang Ke Zhang Jingyi Zhang Pengju Sun Kai Zhu Tianqi Lu Congzhe Wu Kunying Han Kejuan Xu Ming Jin Ying Wang Cheng Zhang Jiayin Deng Yang Song Ziyuan Ouyang Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesSchool of Space Science and PhysicsShandong UniversityWeihai 264209China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China Center for Lunar and Planetary Science Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Geoexploration Science and Technology Jilin UniversityChangchun 130000China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Hawai’i Institute of Geophysics and Planetology Department of Earth SciencesUniversity of Hawai’i at ManoaHonolulu HI 96826USA National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Mining Inner Mongolia University of TechnologyHohhot 010051China University of Chinese Academy of Sciencess Beijing 100049China

Scientific knowledge of lunar lithologies was first acquired in the *** space race between the United States(U.S.)and Soviet Union has promoted numerous manned and robotic lunar exploration *** datasets from these missions,the first series of lunar geologic maps was prepared and published by the *** Survey(USGS)The definition of lunar geological features in these maps was mostly based on morphological characteristics but lacked lithological constraints owing to the incompleteness of the compositional datasets *** two decades of silence,a new era of lunar exploration began in the 1990s when the Galileo spacecraft flew by the Moon during its gravity-assisted *** very successful orbital missions,the Clementine and Lunar Prospector(LP),provided the first global geochemical and mineralogical(multispectral,gamma ray,neutron,etc.)datasets of the lunar surface.

关键词：美国地质勘探局物质成分编研地质综合研究月球表面数据资料 20世纪90年代以来分类体系

Electric field-driven building blocks for introducing multiple gradients to hydrogels

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Protein & Cell 2020年第4期11卷 267-285页

作者： Gang Xu Zhaozhao ding Qiang Lu Xiaoyi Zhang xiaozhong Zhou Liying Xiao Guozhong Lu David L K aplan Department of Orthopedics The Second Affiliated Hospital of Soochow UniversitySuzhou 215000China Department of Bums and Plastic Surgery Engineering Research Center of the Ministry of Education for Wound Repair TechnologyThe Affiliated Hospital of Jiangnan UniversityWuxi 214041China National Engineering Laboratory for Modern Silk&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow UniversitySuzhou 215123China Department of Orthopedics Affiliated Hospital of Xuzhou Medical UniversityLianyungang 222061China Department of Biomedical Engineering Tufts UniversityMedfordMA 02155USA

Gradient biomaterials are considered as preferable matrices for tissue engineering due to better simulation of native *** introduction of gradient cues usually needs special equipment and complex process but is only effective to limited *** of multiple gradients in the hydrogels remains ***,betasheet rich silk nanofibers(BSNF)were used as building blocks to introduce multiple gradients into different hydrogel systems through the joint action of crosslinking and electric *** blocks migrated to the anode along the electric field and gradually stagnated due to the solution-hydrogel transition of the systems,finally achieving gradient distribution of the blocks in the formed *** gradient distribution of the blocks could be tuned easily through changing different factors such as solution viscosity,which resulted in highly tunable gradient of mechanical *** blocks were also aligned under the electric field,endowing orientation gradient *** cargos could be loaded on the blocks and form gradient cues through the same crosslinking-electric field *** building blocks could be introduced to various hydrogels such as Gelatin and NIPAM,indicating the *** niches with multiple gradient cues could be achieved through the ***-based hydrogels with suitable mechanical gradients were fabricated to control the osteogenesis and ***-osteogenic gradient transition was obtained,which stimulated the ectopic osteochondral tissue regeneration in *** versatility and highly controllability of the strategy as well as multifunction of the building blocks reveal the applicability in complex tissue engineering and various interfacial tissues.

关键词： silk building blocks gradients hydrogel tissue regeneration

Sema4C participates in myogenic differentiation in vivo and in vitro through the p38 MAPK pathway

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Sema4C participates in myogenic differentiation in vivo and ...

In vivo evaluation of urokinase-loaded hollow nanogels for sonothrombolysis on suture embolization-induced acute ischemic stroke rat model

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Haitao WU,Xuan WANG,Shuhong LIU,Yan WU,Tong ZHAO,Xiaoping CHEN,Lingling ZHU,Yanrui WU,Xuefeng ding,xiaozhong PENG,Jiangang YUAN,Xiaomin WANG,Wenhong FAN,Ming FAN Department of Brain Protection & Plasticity Research,Beijing Institute of Basic Medical Sciences,Taiping Road 27, Beijing 100850,China Department of Physiology,Capital University of Medical Sciences,Beijing 100054,China State Key Lab of Molecular Biology,Institute of Basic Medical Sciences,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100005,China

＜正＞Sema4C is a member of transmembrane semaphorin proteins which regulate axonal guidance in the developing nervous *** expression of Sema4C was dramatically induced not only during differentiation of C2C12 mouse myoblasts,but also during injury-induced skeletal muscle regeneration.C2C12 cells stably or transiently expressing Sema4C both showed increased myogenic differentiation reflected by accelerated myotube formation and expression of muscle-specific *** of Sema4C elicited p38 phosphorylation directly,and the effects of Sema4C during myogenic differentiation could be abolished by the p38a-specific inhibitor *** of Sema4C by siRNA transfection during C2C12 myoblasts differentiation could suppress the phosphorylation of p38 followed by dramatically diminished myotube ***4C could activate the myogenin promoter during myogenic differentiation. This activation could be abolished by p38 inhibitor *** together,these observations reveal novel functional potentialities of Sema4C which suggest that Sema4C promotes terminal myogenic differentiation in a p38 MAPK-dependent manner,r 2007 Elsevier *** rights reserved.

关键词： Sema4C C2C12 Muscle regeneration Myogenesis Differentiation siRNA p38 MAPKs

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Bioactive Materials 2018年第1期3卷 102-109页

作者： Yuming Teng Haiqiang Jin ding Nan Mengnan Li Chenghe Fan Yuanyuan Liu Pu Lv Wei Cui Yongan Sun Hongjun Hao xiaozhong Qu Zhenzhong Yang Yining Huang Department of Neurology Peking University First HospitalBeijing 100034China State Key Laboratory of Polymer Physics and Chemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Materials and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

The urokinase-type plasminogen activator(uPA)loaded hollow nanogels(nUK)were synthesized by a one-step reaction of glycol chitosan and aldehyde capped poly(ethylene oxide).The resultant formulation is sensitive to diagnostic ultrasound(US)of 2 ***,we evaluated the in vivo sonothrombolysis performance of the nUK on acute ischemic stroke rat model which was established by suture embolization of middle cerebral artery(MCA).Via intravenous(i.v.)administration,the experimental data prove a controlled release of the therapeutic protein around the clots under ultrasound stimulation,leading to enhanced thrombolysis efficiency of the nUK,evidenced from smaller infarct volume and better clinical scores when compared to the *** of free uPA no matter with or without US ***,the preservation ability of the nanogels not only prolonged the circulation duration of the protein,but also resulted in the better blood-brain barrier protection of the nUK formulation,showing no increased risk on the hemorrhagic transformation than the *** work suggests that the nUK is a safe sonothrombolytic formulation for the treatment of acute ischemic stroke.

关键词： Hollow nanogel Ultrasound responsive Urokinase delivery Thrombolysis In vivo evaluation

劳动力匹配、收入分配与资本主义积累的社会结构稳定性

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世界经济 2019年第8期42卷 3-24页

作者：杨小忠丁晓钦南京财经大学经济学院江苏省南京市210046 上海财经大学马克思主义学院

资本主义积累的社会结构(SSA)演进应以劳资关系为研究核心。本文回归到马克思经典理论,用剩余价值率作为判断 SSA稳定与否的标准,在劳动力匹配模型下分析收入分配、剩余价值率与 SSA之间的内在关系。本文发现,长期来看,资本主义 SSA都... 详细信息

资本主义积累的社会结构(SSA)演进应以劳资关系为研究核心。本文回归到马克思经典理论,用剩余价值率作为判断 SSA稳定与否的标准,在劳动力匹配模型下分析收入分配、剩余价值率与 SSA之间的内在关系。本文发现,长期来看,资本主义 SSA都是不稳定的,资本主义灭亡的命运不会因 SSA能缓解资本积累和经济萧条而改变。这主要是因为资本主义对社会福利的损害是以减少岗位、降低工人分配比例和工资为代价的,要提升资本主义的产出,须增强工人组织能力和采取集体工资的谈判方式,而这又危及资本主义体系稳定。因此,SSA的不稳定来自资本主义制度对抗性劳资关系的不可调和,根源于生产资料私人所有制。

关键词：劳动力匹配积累的社会结构剩余价值率资本有机构成