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Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang liu Mingjun liu Xing liu yuan liu Zhu liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan liu Heyang liu Huaqiu liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan yang Xiongtao yang Yanji yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

儿童进行性骨化性纤维发育不良关节病变15例临床分析

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中华儿科杂志 2017年第7期55卷 519-522页

作者：朱佳柳媛杨洋赖建铭苏改秀康闽李胜男周志轩吴凤岐首都儿科研究所附属儿童医院风湿免疫科北京100020 首都儿科研究所附属儿童医院放射科北京100020

目的总结临床诊断的15例进行性骨化性纤维发育不良（FOP）临床特点，分析FOP引起的关节病变特征。方法收集2005年5月至2016年12月首都儿科研究所附属儿童医院住院并临床诊断的15例FOP患儿的病历资料，并进行电话随访，其中2例失访。将... 详细信息

目的总结临床诊断的15例进行性骨化性纤维发育不良（FOP）临床特点，分析FOP引起的关节病变特征。方法收集2005年5月至2016年12月首都儿科研究所附属儿童医院住院并临床诊断的15例FOP患儿的病历资料，并进行电话随访，其中2例失访。将住院和随访资料进行病例观察性回顾性分析，采用Pearson相关性分析法进行相关因素分析。结果15例患儿中，男8例，女7例，起病年龄2（1～6）岁，确诊年龄6（4～9）岁。15例患儿均有足拇趾的短小、外翻畸形及局部骨性包块形成的临床特征。人组时出现关节病变共12例，受累部位依次为：颈椎8例、肩关节7例、髋关节5例、肘关节4例、腕关节3例、下颌关节2例、腰椎2例。确诊年龄和确诊时病程与关节受累数目呈正相关（r=0．523、0．628，P=0．045、0．012）。关节影像学改变轻微。13例接受电话随访，随访时平均病程6（3～7）年。11例病情没有进一步进展，2例病情逐渐加重。3例应用药物治疗对关节病变均无效。结论FOP关节受累原因是异位骨化引起的关节融合。FOP引起关节病变的特点为多关节受累、功能障碍突出，而影像学改变轻。随着患儿年龄增长、病程延长，受累关节数目逐渐增加。

关键词：肌炎,骨化性关节炎儿童随访研究

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li Xue-yuan liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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增施CO_2对温室番茄结果期叶片光合特性的影响

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生态学杂志 2018年第5期37卷 1398-1402页

作者：张振花孙胜刘洋李靖袁宏霞郑金英邢国明山西农业大学园艺学院山西太谷030801

针对日光温室冬春季生产CO_2匮缺严重的现象,以不增施CO_2[(400±25)μmol·mol^(-1)(C0)]为对照,研究增施不同浓度CO_2[(600±25)μmol·mol^(-1)(C_1)、(800±25)μmol·mol^(-1)(C_2)、(1000±25)μmol·mol^(-1)(C_3)]对番茄‘兴海12号’结果期光合色素、净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、胞间CO_2浓度(C_i)以及水分利用率(WUE)等光合特性的影响,旨在明确北方地区日光温室番茄结果期适宜的CO_2浓度,为番茄的生产实践提供理论依据。结果表明:增施不同浓度CO_2后,番茄结果期叶片光合色素含量均明显增加;P_n、C_i和WUE显著提高;G_s和T_r显著下降;且CO_2浓度为(1000±25)μmol·mol^(-1)时效果最佳。增施(1000±25)μmol·mol^(-1)CO_2能有效改善番茄结果期叶片光系统、增强其光合作用,有利于番茄的生长发育。

关键词：番茄 CO2浓度结果期光合特性

基于大型底栖动物完整性指数与综合生物指数的水生态评价

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中国环境科学 2024年第3期44卷 1476-1486页

作者：姚琦黎明杰麻林唐哲朱熠刘阳圆蔡永久燕文明张又李宽意河海大学水灾防御全国重点实验室江苏南京210098 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室江苏南京210008 湖南省水利厅湖南长沙410007 湖南省水文水资源勘测中心湖南长沙410007

针对不同流域部分生物指数评价标准并不统一的问题,利用熵权法构建综合生物指数(CBI)统一模糊评价标准,同时计算底栖动物完整性指数进行评价结果验证.以2021年秋季和2022年春季东洞庭湖10个监测点的数据为基础,通过对25个候选参数逐步筛... 详细信息

针对不同流域部分生物指数评价标准并不统一的问题,利用熵权法构建综合生物指数(CBI)统一模糊评价标准,同时计算底栖动物完整性指数进行评价结果验证.以2021年秋季和2022年春季东洞庭湖10个监测点的数据为基础,通过对25个候选参数逐步筛选,选出M3(软体动物分类单元数)、M9(耐污类群相对丰度)、M13(BI指数)和M22(Shannon-Wiener指数)4个秋季核心参数以及M6(摇蚊个体相对丰度)、M13、M16(BPI指数)和M24(Margalef指数)4个春季核心参数,采用比值法统一量纲后累加计算底栖动物完整性指数,再对BPI、FBI、Shannon-Wiener、BMWP指数客观定权后计算CBI指数划分出5个状态进行对比,结果表明:B-IBI指数和CBI指数均得出靠近出湖河道点位较为健康,湖体点位多为一般和较差,整体秋季健康状况略好于春季,六门闸附近为极差状态,可能是因为该区域是东洞庭湖的闸口之一,常年关闭导致水体流动性较差,开闸放水后沉积物中的淤泥会释放污染物使得湖区总氮超标,进而影响了大型底栖动物的完整性.CBI指数与B-IBI指数以及COD_(Mn)、TLI(∑)指数等相关分析结果良好,表明利用综合生物指数和底栖动物完整性指数结合能为东洞庭湖的水生态健康评价提供参考.

关键词：大型底栖动物生物完整性指数熵权法水生态健康东洞庭湖

冲击点火反应过程中RDX基PBX炸药的热辐射特性

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高压物理学报 2025年第1期39卷 44-52页

作者：施鑫辉杨雷杨雪康洪亮袁文硕刘福生西南交通大学物理科学与技术学院高温高压物理研究所四川成都610031

研究冲击波流场中聚合物黏结炸药的热辐射特性可能是获取相关物质组分温度数据的重要途径。利用二级轻气炮加载技术、瞬态辐射测温方法及粒子速度剖面测量技术,探讨了聚合物黏结炸药/氟化锂窗口界面的热辐射特性及其与界面压力之间的相... 详细信息

研究冲击波流场中聚合物黏结炸药的热辐射特性可能是获取相关物质组分温度数据的重要途径。利用二级轻气炮加载技术、瞬态辐射测温方法及粒子速度剖面测量技术,探讨了聚合物黏结炸药/氟化锂窗口界面的热辐射特性及其与界面压力之间的相关性;同时,还优化了聚合物黏结炸药样品制备方法,显著抑制了包裹气体和界面间隙发光背景,给出了界面辐亮度数据及界面温度数据。结果表明,在连续2次冲击加载过程中,界面温度随时间衰减特征与反应产物的等熵膨胀行为密切相关,界面温度反映了界面处产物温度的演化行为,为直接观测点火反应和起爆释能期间非均质复合炸药的反应产物温度数据提供了一种可行的技术途径。

关键词：聚合物黏结炸药冲击加载界面热辐射点火反应等熵膨胀界面温度

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V-uniform ergodicity for fluid queues

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 82-91页

作者： liu yuan-yuan LI yang School of Mathematics and Statistics New Campus Central South University

In this paper, we show that a positive recurrent ?uid queue is automatically V-uniformly ergodic for some function V ≥ 1 but never uniformly ergodic. This reveals a similarity of ergodicity between a ?uid queue and a quasi-birth-and-death process. As a byproduct of V-uniform ergodicity, we derive computable bounds on the exponential moments of the busy period.

关键词： fluid queues QBD processes ergodicity the extended generator

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao yuan Jun-Bo yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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肺乳头状腺瘤1例并文献复习

中国临床医学影像杂志 2022年第11期33卷 828-830页

作者：刘远洋李琰李祥宇杜运袁金巧唐艳隆大理大学第一附属医院云南大理671000

肺乳头状腺瘤是一种罕见的肿瘤,这种肿瘤细胞缺乏明显的异型、有丝分裂以及Ki-67的高表达,所以通常被认为是一种良性的肿瘤,且不伴有复发及肺内转移。本例旨在应用影像学、组织学、免疫组织化学,对1例右肺中叶伴左肺转移的乳头状腺瘤进... 详细信息

肺乳头状腺瘤是一种罕见的肿瘤,这种肿瘤细胞缺乏明显的异型、有丝分裂以及Ki-67的高表达,所以通常被认为是一种良性的肿瘤,且不伴有复发及肺内转移。本例旨在应用影像学、组织学、免疫组织化学,对1例右肺中叶伴左肺转移的乳头状腺瘤进行报道和文献复习。

关键词：腺瘤病,肺体层摄影术,X线计算机