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Continued evolution of the Eurasian avian-like H1N1 swine influenza viruses in China

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Science China(Life Sciences) 2023年第2期66卷 269-282页

作者： Fei Meng Yan Chen zuchen song Qiu Zhong Yijie Zhang Chuanling Qiao Cheng Yan Huihui Kong Liling Liu Chengjun Li Huanliang Yang Hualan Chen State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China

Animal influenza viruses continue to pose a threat to human public health. The Eurasian avian-like H1N1(EA H1N1) viruses are widespread in pigs throughout Europe and China and have caused human infections in several countries, indicating their pandemic potential. To carefully monitor the evolution of the EA H1N1 viruses in nature, we collected nasal swabs from 103,110pigs in 22 provinces in China between October 2013 and December 2019, and isolated 855 EA H1N1 viruses. Genomic analysis of 319 representative viruses revealed that these EA H1N1 viruses formed eight different genotypes through reassortment with viruses of other lineages circulating in humans and pigs, and two of these genotypes(G4 and G5) were widely distributed in *** studies indicated that some strains have become highly pathogenic in mice and highly transmissible in ferrets via respiratory droplets. Moreover, two-thirds of the EA H1N1 viruses reacted poorly with ferret serum antibodies induced by the currently used H1N1 human influenza vaccine, suggesting that existing immunity may not prevent the transmission of the EA H1N1 viruses in humans. Our study reveals the evolution and pandemic potential of EA H1N1 viruses and provides important insights for future pandemic preparedness.

关键词： H1N1 influenza immunity

三峡地区寒武系纽芬兰统岩家河组小壳化石研究进展

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地学前缘 2020年第6期27卷 104-115页

作者：郭俊锋强亚琴韩健宋祖晨王文哲张志飞长安大学地球科学与资源学院西部矿产资源与地质工程教育部重点实验室陕西西安710054 现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所) 江苏南京210008 西北大学地质学系大陆动力学国家重点实验室陕西西安710069

埃迪卡拉纪—寒武纪转换时期小壳化石的突然出现是世人瞩目的重要演化事件之一,它见证了动物的爆发式快速演化过程,标志着以两侧对称动物为特征的寒武纪生态系统的开始。湖北三峡地区寒武系纽芬兰统岩家河组处于幸运阶—第二阶这一关键... 详细信息

埃迪卡拉纪—寒武纪转换时期小壳化石的突然出现是世人瞩目的重要演化事件之一,它见证了动物的爆发式快速演化过程,标志着以两侧对称动物为特征的寒武纪生态系统的开始。湖北三峡地区寒武系纽芬兰统岩家河组处于幸运阶—第二阶这一关键层段,是研究上述问题的理想地区之一。岩家河组小壳化石研究最近取得的进展,为寒武系纽芬兰统幸运阶/第二阶界线的标定,和寒武纪早期软体动物和刺胞动物的演化及个体发育提供了重要的化石依据,本文对其进行了总结。全球界线层型剖面和点位(GSSP)寒武系第二阶底界划分标志的Watsonella crosbyi和Aldanella attleborensis在岩家河组第5段底部的同时出现,意味着岩家河组第5段已归属寒武系第二阶。这两类软体动物化石均广泛分布于华南、蒙古、西伯利亚和北美等大陆碳酸盐岩相寒武系第二阶地层中,它们均是定义寒武系第二阶底界的有力竞争者。另外,***壳顶下方一对肌肉附着结构的发现提供了重要的软组织结构信息,证实了***为内腹型壳,归属为未扭曲的软体动物太阳女神螺类。新发现六方锥石类Septuconularia yanjiaheensis具侧向压扁、两辐射对称的、14个等大锥面的围鞘,是迄今所描述的六方锥石类中锥面数最多的类型。根据横肋疏密程度,围鞘由下向上可分为三部分,可能代表胚胎期、幼年期和成年期不同的生长阶段。Septuconularia显然由寒武系幸运阶Hexaconularia通过扇面扩增演变而来,证明Hexaconularia可能是Arthrochites和Septuconularia之间的中间过渡类型。新发现的橄榄蛋类Octapyrgites elongatus与幸运阶Olivooides和Quadrapyrgites十分相似,围鞘由方形的壳顶区和波纹状倒宝塔形的远顶区组成。然而Octapyrgites只有8个口折叶,有别于具12个口折叶的Quadrapyrgites。通过与幸运期水母类多种对称方式对比,发现在寒武系第二阶橄榄蛋类数量减少和五辐射对称骨状壳类缺失,表明在幸运期/第二期转换时期,底栖固着型的刺胞动物水母类多样性发生了明显衰落,甚至部分绝灭,而同期的两侧对称动物则迅速辐射演化。

关键词：岩家河组小壳化石第二阶纽芬兰统三峡地区

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华南寒武纪早期刺胞动物演化框架

地学前缘 2020年第6期27卷 67-78页

作者：韩健郭俊锋欧强宋祖晨刘平郝文静孙洁王星西北大学地质学系大陆动力学国家重点实验室与早期生命与环境陕西省重点实验室陕西西安710069 长安大学地球科学与资源学院西部矿产资源与地质工程教育部重点实验室陕西西安710054 中国地质大学(北京)生物地质与环境地质国家重点实验室早期生命演化实验室北京100083 青岛海洋地质研究所山东青岛266071

刺胞动物是华南寒武纪早期海洋生态系统的重要组成部分,针对这类化石的研究有助于深入了解寒武纪多幕式爆发事件。本文主要根据寒武纪早期扬子板块陕南宽川铺生物群、湖北岩家河生物群以及澄江生物群产出的刺胞动物,探讨刺胞动物在寒武... 详细信息

刺胞动物是华南寒武纪早期海洋生态系统的重要组成部分,针对这类化石的研究有助于深入了解寒武纪多幕式爆发事件。本文主要根据寒武纪早期扬子板块陕南宽川铺生物群、湖北岩家河生物群以及澄江生物群产出的刺胞动物,探讨刺胞动物在寒武纪早期的演化框架,取得了以下初步认识。截至目前,所发现的寒武纪早期刺胞动物绝大多数都属于水母超纲,珊瑚纲的化石记录在寒武系幸运阶、第二阶保存较为罕见。其中寒武系幸运阶刺胞动物的化石记录全部属于底栖类型,体型小,且具有多种类型的身体辐射对称形式,绝大多数类型可以确定属于直接发育。第二阶刺胞动物仍以底栖固着类型为主,体形增大,仅见两、四辐射对称形式;而寒武系第三阶刺胞动物仍有底栖固着类型,但游泳的水母开始出现,体型增大明显,代表水母冠群的出现,以及世代交替的复杂生命周期的正式建立。从幸运阶到第三阶刺胞动物体型明显增大,可能与海水氧气含量增加有关。在寒武纪大爆发的背景下,刺胞动物的分异度和丰度在寒武系幸运阶就已经达到顶峰,然后在第二阶、第三阶开始衰减,这种变化可能与两侧对称动物辐射演化有关。华南刺胞动物的化石记录表明,寒武纪大爆发并非纯粹的一幕式爆发,其中充斥着一系列生物群的替代甚至灭绝事件。

关键词：宽川铺生物群岩家河生物群澄江生物群刺胞动物水母生命周期寒武纪演化

Establishing the vector-meson-exchange dominance for the short range interactions of light quarks

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Science China(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 194-195页

作者： Bing-song Zou Department of Physics Tsinghua University CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences Southern Center for Nuclear-Science Theory (SCNT) Institute of Modern Physics Chinese Academy of Sciences

Understanding the interactions between constituent quarks is one of the fundamental and challenging problems in hadron physics. At present, the constituent quark models have achieved great success in describing the properties of hadrons, whereas some long-standing disputes remain, especially for the short range interactions between constituent quarks. In exploring the dynamic mechanism between u/d quarks, it is found that the one gluon exchange and/or vector meson exchange induced interactions may dominate the short range interactions [1].

关键词： quark exchange meson

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峡东寒武纪第二期三管缠绕形壳Anabarites ***的螺旋手性

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地质学报 2024年第7期98卷 2025-2040页

作者：彭佳欣赵晓芳郭俊锋强亚琴宋祖晨孙洁韩健长安大学地球科学与资源学院西部矿产资源与地质工程教育部重点实验室陕西西安710054 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069

在现生生物和化石记录中螺旋手性十分常见,然而,其发生机制一直悬而未决,尤其是寒武纪早期小壳化石。阿纳巴管类(anabaritids)是一类广布于寒武纪纽芬兰世地层中呈明显三辐射对称的管状化石,前人对该类化石中螺旋扭转属种的研究大多仅... 详细信息

在现生生物和化石记录中螺旋手性十分常见,然而,其发生机制一直悬而未决,尤其是寒武纪早期小壳化石。阿纳巴管类(anabaritids)是一类广布于寒武纪纽芬兰世地层中呈明显三辐射对称的管状化石,前人对该类化石中螺旋扭转属种的研究大多仅限于形态描述,其手性机制讨论甚少。本文依托湖北宜昌寒武系纽芬兰统岩家河组中111枚右手螺旋手性的小壳化石——Anabarites ***,探讨该类化石右手螺旋模式生长机制,认为螺旋扭转原因并非外部环境所致(水流变化、埋藏作用、科里奥利力),而应从生物自身因素(功能形态学、分子发育生物学)出发探究其固定的右旋不对称性机制。

关键词：螺旋手性功能形态学分子发育生物学 Anabarites cf.tripartitus 寒武系第二阶

Bilinear magnetoelectric resistance induced by spin Hall effect

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Science China Materials 2025年第2期68卷 687-688页

作者： Ruiyue Chu Cheng song School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Magnetoresistance(MR)is a fundamental transport phenomenon crucial for reading magnetic *** also plays a key role in understanding how time-reversal symmetry breaking affects electrical *** discoveries of anisotropic MR[1],giant MR[2],tunneling MR[3],and spin Hall magnetoresistance[4]have driven the development of diverse spintronic devices used in data storage,computing,and sensing ***,these MR effects do not scale linearly with the electric field(and thus,electric current).Recently,nonlinear MR,which scales specifically with the electric current(Ic),has been *** magnetic/non-magnetic bilayers,unidirectional spin Hall magnetoresistance(USMR)[5]shows a linear dependence on Ic,with voltage scaling quadratically with the applied electric field,due to interfacial spin-dependent and electron-magnon scattering mechanisms.

关键词： breaking symmetry linearly

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth Sciences 2025年第1期68卷 270-296页

作者： song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China CAS Center of Excellence in Comparative Planetary Studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Disordered hyperuniformity and thermal transport in monolayer amorphous carbon

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 145-152页

作者： Nianjie Liang Yuxi Wang Bai song Department of Energy and Resources Engineering Peking UniversityBeijing 100871China Department of Advanced Manufacturing and Robotics Peking UniversityBeijing 100871China

Disordered hyperuniformity(DHU)is a recently discovered novel state of amorphous systems characterized by strongly suppressed density fluctuations at large length scales as in crystalline materials,which offers great potential for achieving unusual mechanical,electronic,and photonic ***,despite the fundamental and technological importance of thermal transport in amorphous solids,the effect of DHU remains largely ***,we theoretically study thermal transport in a class of two-dimensional DHU materials—monolayer amorphous carbon(MAC).Beginning with a perfect graphene lattice,we continuously apply Stone-Wales transformations to generate a series of MAC models with varied degrees of disorder and defects,which are quantified through comprehensive structural analysis including the so-called hyperuniformity index(H),where a smaller H indicates a higher degree of ***,we conduct molecular dynamics simulations to obtain the thermal conductivity(κ).A significant correlation between the thermal transport behavior and degree of hyperuniformity is observed,with the room-temperatureκdecreasing from 26.3 to 5.3 W m^(-1)K^(-1)while H is tuned from 0.0004 to ***,two distinct transport regimes are identified,including a nearly-DHU regime at small H(<0.005)whereκdrops sharply and a non-DHU region at larger H whereκbecomes relatively ***-resolved analysis reveals longer lifetime and higher participation ratio for the heat carriers in nearly-DHU MAC,implying that the hidden long-range correlations could support extended modes that enhance *** work highlights the impact of DHU on the thermal properties of amorphous materials and represents a conceptual advancement that is worthy of future exploration.

关键词： disordered hyperuniformity thermal transport amorphous material two-dimensional monolayer amorphous carbon

Unifying Fixed Time and Prescribed Time Control for Strict-Feedback Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 347-355页

作者： Xiang Chen Yujuan Wang Yongduan song the State Key Laboratory of Power Transmission Equipment & System Security and New Technology and School of Automation Chongqing University IEEE

This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output(MIMO)nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and non-vanishing uncertainties make the prescribed-time control problem become much more nontrivial. The solution to address the challenges mentioned above involves incorporating a prescribed-time filter, as opposed to a finite-time filter, and formulating a prescribed-time Lyapunov stability lemma(Lemma 5). The prescribed-time Lyapunov stability lemma is based on time axis shifting time-varying yet bounded gain, which establishes a novel link between the fixed-time and prescribed-time control method. This allows the restriction condition that the time-varying gain function must satisfy as imposed in most exist prescribed-time control works to be removed. Under the proposed control method, the desire trajectory is ensured to closely track the output of the system in prescribed time. The effectiveness of the theoretical results are verified through numerical simulation.

关键词： Prescribed-time control prescribed-time filter robust control state feedback strict-feedback systems