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Formation reconfiguration in restricted three body problem

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Acta Mechanica Sinica 2007年第3期23卷 321-328页

作者： Shengping gong junfeng Li Hexi Baoyin Yunfeng Gao School of Aerospace Tsinghua UniversityBeijing 100084 China

Reconfiguration of formation flying around a halo orbit of the Sun-Earth restricted three body system is investigated with impulse maneuvers. For a short time reconfiguration, the two-impulse maneuver is investigated with both analytical and numerical methods and the Beginning-Ending （BE） method is proven to be an energy-optimal one of all two-impulse （TI） reconfigurations, and the energy consumption of BE is independent of the position of the chief spacecraft, and decreases with the reconfiguration time. Then, genetic algorithm is adopted to optimize the energy consumption. The results show that the optimal energy increases with radius difference between the initial and final orbits, and decreases with the reconfiguration time.

关键词： Three body problem Halo orbit Formation reconfiguration Formation flying

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实用临床医药杂志 2024年第10期28卷 136-140页

作者：龚俊峰张燕罗琰琨山西医科大学第五临床医学院肾内科山西太原030001

新型冠状病毒感染(COVID-19)可诱发患者凝血功能障碍,且与血栓并发症(微血管血栓形成、静脉血栓栓塞、脑卒中)风险升高相关。在维持性血液透析患者中,COVID-19相关凝血功能障碍及血栓并发症的发生风险将进一步升高。本文综述维持性血液... 详细信息

新型冠状病毒感染(COVID-19)可诱发患者凝血功能障碍,且与血栓并发症(微血管血栓形成、静脉血栓栓塞、脑卒中)风险升高相关。在维持性血液透析患者中,COVID-19相关凝血功能障碍及血栓并发症的发生风险将进一步升高。本文综述维持性血液透析患者COVID-19相关高凝状态及血栓并发症的发病机制,以期为该疾病的诊治提供参考依据。

关键词：维持性血液透析新型冠状病毒感染严重急性呼吸综合征冠状病毒2型凝血血栓

华南沿海地区白垩纪花岗岩多期构造裂缝发育特征及其对潜山勘探的指示

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地球科学 2024年第7期49卷 2570-2588页

作者：孙侨阳邓洪旦纪沫龚俊峰董方孙思瑶王云龙于志泉浙江大学地球科学学院浙江杭州310058 教育部含油气盆地构造研究中心浙江杭州310058 中海石油(中国)有限公司北京研究中心北京100027

裂缝的分布特征对花岗岩储层研究具有重要作用.结合无人机遥感技术和野外调查对华南沿海地区白垩纪花岗岩露头的构造裂缝进行数字化识别和定量研究.分析表明:研究区主要发育NE20°~40°和SE100°~140°两组裂缝,NE向裂缝形成时间早于SE... 详细信息

裂缝的分布特征对花岗岩储层研究具有重要作用.结合无人机遥感技术和野外调查对华南沿海地区白垩纪花岗岩露头的构造裂缝进行数字化识别和定量研究.分析表明:研究区主要发育NE20°~40°和SE100°~140°两组裂缝,NE向裂缝形成时间早于SE向;多期构造变形会显著提高裂缝网络的连通度和面密度,连通度高值区广泛分布,面密度高值区集中分布在辉绿岩脉侵入区和断裂带内部;构造裂缝网络的线密度、面密度和连通度与断裂带规模呈正相关.构建了华南沿海地区白垩纪花岗岩多期构造裂缝的发育模式,指出断裂带和辉绿岩脉侵入区等裂缝交汇部位有利于形成优势储层,为海域花岗岩潜山的勘探开发提供重要指示.

关键词：花岗岩储层构造裂缝裂缝网络无人机遥感拓扑几何分析构造地质学

The Exhumation History of North Qaidam Thrust Belt Constrained by Apatite Fission Track Thermochronology:Implication for the Evolution of the Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 870-883页

作者： CHENG Xiaogan LIN Xiubin WU Lei CHEN Hanlin XIAO Ancheng gong junfeng ZHANG Fengqi YANG Shufeng School of Earth Sciences Zhejiang UniversityHangzhou 310027ZhejiangChina Research Center for Structures in Oil-and Gas-Bearing Basins Ministry of EducationHangzhou 310027ZhejiangChina

Determining the spatio-temporal distribution of the deformation tied to the India-Eurasian convergence and the impact of pre-existing weaknesses on the Cenozoic crustal deformation is significant for understanding how the convergence between India and Eurasia contributed to the development of the Tibetan Plateau. The exhumation history of the northeastern Tibetan Plateau was addressed in this research using a new apatite fission track （AFT） study in the North Qaidam thrust belt （NQTB）. Three granite samples collected from the Qaidam Shan pluton in the north tied to the Qaidam Shan thrust, with AFT ages clustering in the Eocene to Miocene. The other thirteen samples obtained from the Luliang Shan and Yuka plutons in the south related to the Luliang Shan thrust and they have showed predominantly the Cretaceous AFT ages. Related thermal history modeling based on grain ages and track lengths indicates rapid cooling events during the Eocene-early Oligocene and since late Miocene within the Qaidam Shan, in contrast to those in the Cretaceous and since the Oligocene-Miocene in the Luliang Shan and Yuka region. The results, combined with published the Cretaceous thermochronological ages in the Qaidam Shan region, suggest that the NQTB had undergo rapid exhumation during the accretions along the southern Asian Andean-type margin prior to the India-Eurasian collision. The Cenozoic deformation initially took place in the North Qaidam thrust belt by the Eocene, which is consistent with the recent claim that the deformation of the northeastern Tibetan Plateau initiated in the Eocene as a response to continental collision between India and Eurasia. The immediate deformation responding to the collision is tentatively attributed to the preexisting weaknesses of the lithosphere, and therefore the deformation of the northeastern Tibetan Plateau should be regarded as a boundary-condition-dependent process.

关键词： apatite fission track Qaidam Shan Luliang Shan North Qaidam thrust belt Tibetan plateau

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熔窑后期熔化引起微小气泡的治理

玻璃 2024年第4期51卷 44-46页

作者：陈德成宫俊峰谭利关岭雷佳武汉长利新材料科技股份有限公司武汉430090 秦皇岛经济技术开发区民生保障局秦皇岛066000

浮法工艺是成熟工艺,很多板面气泡根据分布、大小等特点较容易找到原因并快速采取相应措施,但板面杂乱无章的微小气泡由于产生原因很多,逐一排除时会因为时间较长而影响产质量。就目前具体生产中遇到的因熔化原因引起的微小气泡的整治... 详细信息

浮法工艺是成熟工艺,很多板面气泡根据分布、大小等特点较容易找到原因并快速采取相应措施,但板面杂乱无章的微小气泡由于产生原因很多,逐一排除时会因为时间较长而影响产质量。就目前具体生产中遇到的因熔化原因引起的微小气泡的整治过程进行分析,通过逐一排查,探究原因,为浮法玻璃生产中气泡的来源提供思考和借鉴。

关键词：气泡浮法玻璃澄清熔化控制

动态对比增强磁共振成像联合人工智能预测乳腺癌新辅助化疗疗效的价值分析

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中国医学装备 2024年第4期21卷 55-59页

作者：龚俊峰王永杰丁宇薛周沈高耀上海新华医院崇明分院医学影像科上海202150

目的:探讨基于人工智能(AI)技术动态对比增强磁共振成像(DCE-MRI)预测乳腺癌新辅助化疗疗效的价值。方法:收集2018年1月至2020年12月上海新华医院崇明分院收治的进行新辅助化疗治疗的89例乳腺癌患者,依据治疗效果将其分为有效组(36例)... 详细信息

目的:探讨基于人工智能(AI)技术动态对比增强磁共振成像(DCE-MRI)预测乳腺癌新辅助化疗疗效的价值。方法:收集2018年1月至2020年12月上海新华医院崇明分院收治的进行新辅助化疗治疗的89例乳腺癌患者,依据治疗效果将其分为有效组(36例)和无效组(53例),新辅助化疗前和第4疗程结束后进行DCE-MRI检查,绘制时间-信号强度曲线,测定容量转移常数(K^(trans))、速率常数(K^(ep))以及血管外间隙容积比(V_(e))。扩充原始DCE-MRI图像,提取包含病灶的感兴趣区域,运用深度卷积神经网络进行卷积运算,通过训练集获得分类模型。绘制受试者工作特征(ROC)曲线,选择ROC曲线下面积(AUC)最高的验证集模型作为最终模型,以测试集评价模型性能。结果:化疗后,DCE-MRI检查,有效组患者K^(trans)(0.67±0.15)、K^(ep)(1.22±0.24)显著小于无效组,ΔK^(trans)(1.51±0.18)、ΔK^(ep)(2.31±0.26)显著大于无效组,差异均有统计学意义(t=23.072、20.016;P<0.05);ΔK^(trans)、ΔK^(ep)及ΔV_(e)预测乳腺癌新辅助化疗疗效的AUC分别为0.814、0.839和0.432,三者联合检测的灵敏度、特异度及AUC分别为89.93%、83.48%和0.845,预测价值高于单项检测。DCEMRI-AI模型对乳腺癌新辅助化疗疗效具有较高的预测效能,其训练集、验证集及测试集的AUC分别为0.897、0.869和0.859。在训练集和验证集中,DCE-MRI-AI模型和DCE-MRI模型对乳腺癌新辅助化疗疗效的预测效能差异具有统计学意义(Z_(训练集)=2.435,P<0.05;Z_(验证集)=2.147,P<0.05)。结论:AI技术应用于DCE-MRI有助于提高对乳腺癌新辅助化疗疗效的预测效能,为治疗及预后评估提供可靠数据,具有临床应用价值。

关键词：乳腺癌新辅助化疗动态对比增强磁共振成像(DCE-MRI) 人工智能(AI) 卷积神经网络疗效评价

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Evidences of rapid erosion driven by climate in the Yarlung Zangbo (Tsangpo) Great Canyon,the eastern Himalayan syntaxis

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Chinese Science Bulletin 2011年第11期56卷 1123-1130页

作者： YU XiangJiang JI JianQing gong junfeng SUN DongXia QING JianChun WANG LiNing ZHONG DaLai ZHANG ZhiCheng Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Climate and tectonism are both particularly intense in the Yarlung Zangbo (Tsangpo) Great Canyon in the eastern Himalayan syntaxis,which is characterized by the most rapid landscape evolution of anywhere in the ***,the eastern Himalayan syntaxis is one of the best locations to study the interactions between climate and *** paper investigates the cooling ages of the Doxong La-Baibung profile using apatite fission track (AFT) dating on 11 bedrock samples at elevations ranging from 4210 to 710 *** are topographic,climatic,metamorphic,and thermochronological gradients in the profile,providing good conditions to study interactions between climate and *** ages ranged from 4.6±0.6 Ma to 1.7±0.3 Ma,and the mean fission track lengths ranged from 11.0 to 12.4 μ*** was found that the cooling rates revealed by AFT ages increased with decreasing ***,the tendency of the cooling rates revealed by the 40 Ar-39 Ar ages was different from that indicated by the AFT ***,for most districts of the eastern Himalayan syntaxis,the compiled AFT age distribution correlates well with the annual average precipitation,indicating the coupling of the cooling and erosion rates of the near-surface rock and *** geothermal history modeling results indicate an obvious increase in the cooling and erosion rate between 1.0 and 0.5 *** age is consistent with other research findings for this time,when the vapor channel of the Yarlung Zangbo Great Canyon began to take *** evidences suggest that climate,especially precipitation,has acting as a key factor influencing the rapid cooling and erosion in the Yarlung Zangbo Great Canyon since 1-0.5 Ma.

关键词：东喜马拉雅构造结雅鲁藏布江大峡谷雅鲁藏布大峡谷侵蚀速率气候证据年平均降水量冷却年龄

Injectable cartilage matrix hydrogel loaded with cartilage endplate stem cells engineered to release exosomes for non-invasive treatment of intervertebral disc degeneration

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Bioactive Materials 2022年第9期7卷 29-43页

作者： Liwen Luo junfeng gong Zhouguang Wang Yao Liu Jiaming Cao Jinghao Qin Rui Zuo Hongyu Zhang Shuai Wang Ping Zhao Di Yang Mengjie Zhang Yanqiu Wang junfeng Zhang Yue Zhou Changqing Li Bing Ni Zhiqiang Tian MingHan Liu Department of Orthopaedics Xinqiao HospitalArmy Medical University(Third Military Medical University)ChongqingChina Institute of Immunology PLAArmy Medical University(Third Military Medical University)ChongqingChina Molecular Pharmacology Research Center School of Pharmaceutical ScienceWenzhou Medical UniversityWenzhou325000ZhejiangChina Department of Orthopaedics The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhou325000ZhejiangChina Department of Pharmacy Daping HospitalArmy Medical University(Third Military Medical University)ChongqingChina Institute of Geophysics and Geomatics China University of GeosciencesWuhanChina Department of Emergency Second Affiliated Hospital of Chongqing Medical UniversityChongqingChina Institute of Pathology and Southwest Cancer Center Southwest HospitalArmy Medical University(Third Military Medical University)ChongqingChina State Key Laboratory of Silkworm Genome Biology Biological Science Research CenterSouthwest UniversityChongqingChina Department of Pathophysiology College of High Altitude Military MedicineArmy Medical UniversityChongqingChina Key Laboratory of Extreme Environmental Medicine Ministry of Education of ChinaArmy Medical University(Third Military Medical University)ChongqingChina Institute of Hepatopancreatobiliary Surgery Chongqing General HospitalUniversity of Chinese Academy of SciencesChongqingChina

Low back pain,mainly caused by intervertebral disc degeneration(IVDD),is a common health problem;however,current surgical treatments are less than ***,it is essential to develop novel non-invasive surgical methods for IVDD ***,we describe a therapeutic strategy to inhibit IVDD by injecting hydrogels modified with the extracellular matrix of costal cartilage(ECM-Gels)that are loaded with cartilage endplate stem cells(CESCs).After loaded with CESCs overexpressing Sphk2(Lenti-Sphk2-CESCs)and injected near the cartilage endplate(CEP)of rats in vivo,ECM-Gels produced Sphk2-engineered exosomes(Lenti-Sphk2-Exos).These exosomes penetrated the annulus fibrosus(AF)and transported Sphk2 into the nucleus pulposus cells(NPCs).Sphk2 activated the phosphatidylinositol 3-kinase(PI3K)/p-AKT pathway as well as the intracellular autophagy of NPCs,ultimately ameliorating *** study provides a novel and efficient non-invasive combinational strategy for IVDD treatment using injectable ECM-Gels loaded with CESCs that express Sphk2 with sustained release of functional exosomes.

关键词： Intervertebral disc degeneration Engineered exosomes Hydrogels Extracellular matrix of costal cartilage Sphingosine kinase 2

Developmental Patterns and Gender Differences of Vocal Production in Marmoset Monkeys

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Neuroscience Bulletin 2024年第1期40卷 133-138页

作者： Ruixin An Chaocheng Lu Chen Wang Liangtang Chang junfeng Huang Fan Jiang Tian-Le Xu Neng gong Center for Brain Science Shanghai Children's Medical CenterShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Anatomy and Physiology Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Critical Care Medicine Huashan HospitalFudan University12 Middle Wulumuqi RoadShanghai 200040China Institute of Neuroscience Key Laboratory of Primate NeurobiologyCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China Lingang Laboratory Shanghai 200031China Shanghai Center for Brain Science and Brain-Inspired Technology Shanghai 201210China

Dear Editor,The common marmoset(Callithrix jacchus),a small New World monkey species,is considered an ideal non-human primate model for studying the evolution and neural mechanism of vocal behavior due to their rich call repertoire and vocal communication[1-3].Especially,the early vocal development of marmoset monkeys has attracted much attention,because newborn marmosets have been shown to exhibit a vocal development *** two months after birth,marmosets'vocalizations undergo dramatic changes from cries to adult-like mature calls,a process that is influenced not only by inner physical maturation but also by parental care and feedback[4].

关键词： parental birth Pattern