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Exceptional Early Jurassic fossils with leathery eggs shed light on dinosaur reproductive biology

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National Science Review 2024年第6期11卷 146-158页

作者： Fenglu Han Yilun Yu Shukang Zhang Rong Zeng Xinjin Wang Huiyang Cai Tianzhuang Wu Yingfeng Wen Sifu Cai Chun Li Rui Wu Qi Zhao Xing Xu School of Earth Sciences China University of Geosciences (Wuhan) Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences University of Chinese Academy of Sciences Guizhou Provincial Museum Guizhou Provincial institute of cultural relics and Archaeology Pingba institute of cultural relics Administration Centre for Vertebrate Evolutionary Biology Yunnan University

Our understanding of pre-Cretaceous dinosaur reproduction is hindered by a scarcity of evidence within fossil records. Here we report three adult skeletons and five clutches of embryo-containing eggs of a new sauropodomorph from the Lower Jurassic of southwestern China, displaying several significant reproductive features that are either unknown or unlike other early-diverging sauropodomorphs, such as relatively large eggs with a relatively thick calcareous shell formed by prominent mammillary cones, synchronous hatching and a transitional prehatching posture between the crocodilians and living birds. Most significantly,these Early Jurassic fossils provide strong evidence for the earliest known leathery eggs. Our comprehensive quantitative analyses demonstrate that the first dinosaur eggs were probably leathery, elliptical and relatively small, but with relatively long eggshell units, and that along the line to living birds, the most significant change in reptilian egg morphology occurred early in theropod evolution rather than near the origin of Aves.

关键词： dinosaur sauropodomorph Jurassic embryo egg evolution reproductive behavior

Feeding prehistoric coastal community:A study of marine faunal remains at the Jingtoushan site

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Science China Earth Sciences 2024年第5期67卷 1574-1590页

作者： Endong WU Guoping SUN Ying ZHANG School of Culture History and LanguageAustralian National UniversityCanberra 2600Australia Zhejiang Provincial institute of cultural relics and Archaeology Hangzhou 310012China National Centre for Archaeology Beijing 100013China

This article examines the abundant marine mollusc,and fish remains at the Jingtoushan shell midden(8,300 to7,800 cal a BP)in Zhejiang Province,China,to investigate the fishing economy,community development,the palaeoenvironment,and their interactions among the prehistoric populations in the lower Yangtze River Basin and southeastern coastal *** also attempts to explore the prosperity and decline of coastal settlements in China during the Neolithic Age and the potential reasons for their rise and fall,*** on the ecological and biological principles of marine animals,standard zooarchaeological methods and radiocarbon dating analysis are used for sampling,identification,measurement,and *** show that at least 11 mollusc taxa and 14 fish taxa can be identified from the Jingtoushan faunal *** ancient Jingtoushan residents possibly lived in a settlement close to the coast and engaged in inshore and offshore fishing,hunting,and gathering as their primary subsistence strategies,with low-level rice cultivation as a supplementary means of ***,the changes in the coastal environment could be one of the reasons why the Jingtoushan residents abandoned their *** research contributes to Chinese Neolithic archaeology with new evidence of the exploitation of marine resources around 8000 a BP in the eastern coastal areas and the relationship between Neolithic community development and environmental changes.

关键词： Neolithic Age Marine faunal remains Fishing economy Palaeoenvironment Community development

Nondestructive Nonlinear Optical Microscopy Revealed the Blackening Mechanism of Ancient Chinese Jades

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Research 2024年第3期2023卷 391-399页

作者： Yaxin Chen Rong Wang Minbiao Ji State Key Laboratory of Surface Physics and Department of Physics Human Phenome InstituteAcademy for Engineering and TechnologyKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)Yiwu Research Institute of Fudan UniversityFudan UniversityShanghai 200433China Department of cultural Heritage and Museology Fudan UniversityShanghaiChina

Jade is most valued in Chinese culture since ancient times. For unearthed jade artifacts, the alteration color resulting from weathering effects and human activities provides information for cultural heritage conservation, archaeology, and history. Currently, the noninvasive 3-dimensional characterization of jade artifacts with high chemical and spatial resolution remains challenging. In this work, we applied femtosecond pump–probe microscopy and second harmonic generation microscopy techniques to study the black alteration of an ancient jade artifact of the late Spring and Autumn period (546 to 476 BC). The direct cause of the “mercury alteration” phenomena was discovered to be the conversion of metacinnabar from buried cinnabar in the tomb. Furthermore, a 3-dimensional optical reconstruction of the black alteration was achieved, providing a high-resolution method for analyzing the blackening mechanism without the need of sample damage. Our approach opens up new opportunities to extract microscopic spatiochemical information for a broad range of alteration colors in jade artifacts.

关键词： pump Nonlinear buried

The earliest evidence for a microblade adaptation in the remote,high altitude regions of the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1561-1573页

作者： Yingshuai JIN Xiaoling ZHANG Shejiang WANG Junyi GE Wei HE Wa DA Yunyao TAN Ziyi YANG Christopher MORGAN Xing GAO institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China cultural relics Conservation institute of the Xizang Autonomous Region Lhasa 850000China Nagqu Culture and Tourism Bureau Nagqu 852000China University of Nevada Reno 89557USA

Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the *** microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the *** timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains *** this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior *** analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North *** Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 *** date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the *** together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.

关键词： The interior of Tibetan Plateau Nwya Devu locality 3 Microblade Early Holocene High altitude adaption

Prehistoric Jade Artifacts of China

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China Book International 2024年第2期 92-97页

作者： Mou Yongkang Fang Xiangming 不详 Zhejiang Provincial institute of cultural relics and Archaeology Zhejiang Archaeological Society Zheijiang cultural relics Appraisal Committee

In this book,*** Yongkang,a senior figure in Zhejiang archaeology,revisits the concept of the"Jade Age."Centered on the theme of prehistoric jade artifacts,he explores their distribution areas,carving techniques,historical context of assembly,the emergence and combination of ceremonial jade sets,and their symbolic meanings,asserting that ancient jade is a crucial medium for exploring Eastern ideological forms.

关键词： Eastern historic symbolic

Status and trends in the stability of the three largest ice shelves in Antarctica

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Science China Earth Sciences 2024年第8期67卷 2615-2632页

作者： Rongxing LI Guojun LI Lu AN Menglian XIA Da LV Yuan CHENG Aiguo ZHAO Tian CHANG Xiangbin CUI Shengkai ZHANG Shijie LIU Yixiang TIAN Weian WANG Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China College of Surveying and Geo-informatics Tongji UniversityShanghai 200092China Postdoctoral Research Station of Shanghai Surveying and Mapping institute Shanghai 200063China Key Laboratory of Spatial-temporal Big Data Analysis and Application of Natural Resources in Megacities Shanghai 200063China institute for Conservation of cultural Heritage School of Cultural Heritage and Information ManagementShanghai UniversityShanghai 200444China Polar Research institute of China Shanghai 200136China Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China

The Ross,Filchner-Ronne,and Amery ice shelves are the three largest ice shelves in Antarctica,playing a crucial role in supporting the Antarctic ice ***,current studies on the stability of the three largest ice shelves primarily focus on singular or limited factors,lacking a comprehensive assessment of multiple *** systematically and in-depth study the stability and trend of the three largest ice shelves,we comprehensively collected and analyzed key parameters,including elevation changes,basal melting,surface meltwater,major rifts propagation rate,suture zones,ice front area change rate,grounding lines,ice velocity,and mass ***,we selected the collapsed Larsen B Ice Shelf(LBIS),the rapidly changing and structurally weakened Pine Island Ice Shelf(PIIS),and the accelerating Totten Ice Shelf(TIS)as reference ice *** comparing and analyzing the key parameters between these reference ice shelves and the three largest ice shelves,we find the status and trends in the stability of the *** findings reveal that most key parameters of the three largest ice shelves present relatively minor variations compared to those of the reference ice ***,50%of the parameters are smaller than those of the accelerating TIS,88%are smaller than those of the rapidly changing PIIS,and all parameters are smaller than those of the collapsed ***,after analyzing parameters that are not smaller than those of the TIS,it is observed that they remain in a stable ***,the three largest ice shelves are currently undergoing natural changes that do not threaten their stability in the short ***,the evolution of the ice shelves under global climate change remains uncertain,making long-term observation and monitoring essential to assess their impact on sea level rise.

关键词： Three largest ice shelves in Antarctica Key parameters Remote sensing monitoring Ice shelf stability Sea level change

Layerwise third-order shear deformation theory with transverse shear stress continuity for piezolaminated plates

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Chinese Journal of Aeronautics 2024年第9期37卷 490-505页

作者： Yingshan GAO Shunqi ZHANG Wei HU Songyun MA Bernd MARKERT School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China Key Laboratory of Silicate cultural relics Conservation(Shanghai University) Ministry of EducationShanghai 20044China institute of General Mechanics RWTH Aachen UniversityAachen 52062Germany

Regarding laminated structures,an electromechanically coupled Finite Element(FE)model based on Layerwise Third-Order Shear Deformation(LW-TOSD)theory is proposed for sta-tic and dynamic ***-TOSD ensures the continuity of in-plane displacements and trans-verse shear *** current LW-TOSD can be applied to arbitrary multi-layer laminated structures with only seven Degrees of Freedom(DOFs)for each element node and eliminates the use of the shear correction ***,a shear penalty stiffness matrix is constructed to sat-isfy artificial constraints to optimize the structural shear strain.A dynamic finite element model is obtained based on LW-TOSD using the Hamilton's ***,the accuracy of the current model is validated by comparing with literature and ABAQUS ***,this study carries out numerical investigations of piezolaminated structures for different width-to-thickness ratios,length-to-width ratios,penalty stiffness matrix,boundary conditions,electric fields and dynamics.

关键词： Laminated structures Piezolaminated structures Third-order shear deformation theory Shear stress continuity Electromechanically coupled

Qujialing relics Site:Testament to Civilization in Middle Reaches of Yangtze River

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China News Release 2024年第6期 102-105页

作者： Tao Yang the Hubei Provincial institute of cultural relics and Archaeology (HICA)

China released a list of the top 10 archaeological findings of 2023 on March 22,2024,with the Qujialing relics site in central China's Hubei Province listed as one of *** Qujialing relics site dates back between 5,900 and 4,200 years and is a major Neolithic relics *** in the transition belt between the southern foothills of Dahong Mountain and the Jianghan Plain,with Qujialing at its core,the site occupies an area of approximately 2.84 million square meters,integrating over 10 spots,including Yinjialing,Zhongjialing and Zhongziba.

关键词： Yangtze Middle listed

Ordered mesoporous nanofibers mimicking vascular bundles for lithium metal batteries

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National Science Review 2024年第5期11卷 291-302页

作者： Xiaohang Zhu Mengmeng Liu Fanxing Bu Xin-Yang Yue Xiang Fei Yong-Ning Zhou Anqi Ju Jianping Yang Pengpeng Qiu Qi Xiao Chao Lin Wan Jiang Lianjun Wang Xiaopeng Li Wei Luo State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional Materials College of Materials Science and Engineering Donghua University institute for Conservation of cultural Heritage Shanghai University Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong University Department of Materials Science Fudan University

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene（PS） homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

关键词： ordered mesoporous nanofibers electrospinning oriented micelles lithium metal batteries