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Theory and classification of mass extinction causation

National Science Review 2024年第1期11卷 16-36页

作者： Thomas J.Algeo Jun Shen State Key laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(e.***.solar flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle changes.In this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial during the Late Ordovician and Late Devonian events,

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

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Microbes in mass extinction: an accomplice or a savior?

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National Science Review 2024年第1期11卷 12-15页

作者： Genming Luo Deng Liu Hao Yang China University of geosciences (Wuhan) State Key laboratory of Geobiology and Environmental Geology

Microbes include various types of organisms that are invisible to the naked eye,e.g. bacteria, archaea and microeukaryotes. Although the precise number remains largely unknown, microbes are recognized as the unseen majority of our biosphere [1]. As a group of organisms classified by body size, microbes cover a considerable spectrum of metabolisms,

关键词： AFTERMATH

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Mass extinctions, their causes and consequences: an interview with Douglas H.Erwin and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng Xie State Key laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public alike.NSR spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

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Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin

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Journal of Ocean University of China 2024年第3期23卷 643-653页

作者： GUO Kun ZHAI Shikui FAN Di ZHANG Xia ZHANG Yu ZHU Zhimin Laoshan laboratory Qingdao 266237China Key laboratory of Submarine geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Key laboratory of Submarine geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental margin.The clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and Ti.The clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the magma.The calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 kbar.The geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of clinopyroxene.Combined with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust.

关键词： trace elements clinopyroxenes southern Okinawa Trough seafloor spreading back-arc basin

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Bioinspired 3D flexible devices and functional systems

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National Science Review 2024年第3期11卷 271-295页

作者： Xu Cheng Zhangming Shen Yihui Zhang applied Mechanics laboratory Department of Engineering Mechanics Tsinghua University laboratory of Flexible Electronics Technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration.Intractable challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

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Auto-Detection Method Using Convolution Neural Network for Bottom-Simulating Reflectors

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Journal of Ocean University of China 2024年第3期23卷 683-694页

作者： XU Haowei XING Junhui YANG Boxue LIU Chuang Key laboratory of Submarine geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

In studies on gas hydrate,bottom-simulating reflectors(BSR)are used to determine the potential hydrate-bearing sedimentary layers.Usually,BSR detection is performed manually by experienced interpreters.Therefore,a method for implementing an auto-matic BSR detection process should be established.In this study,we develop a novel architecture for BSR characterization using the convolutional neural network(CNN)technique.We propose the use of Stokes’transform(ST)to obtain a time-frequency spectrum for the input of CNN.ST fully uses the frequency content of the seismic data,and a part of the 3D seismic data collected from the Blake Ridge is utilized to train the CNN.Synthetic seismic records with variable signal-to-noise ratios(SNR),as well as Blake Ridge seismic data,were used to validate the detection effect of the CNN.Results show that the CNN trained by this method exhibits excellent performance in noise-resistant testing and achieves an accuracy of more than 89% in field seismic data detection.

关键词： BSR CNN Stocks’transform gas hydrate Blake Ridge

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Yolk-shell FeSe_(2)@CoSe_(2)/FeSe_(2) heterojunction as anode materials for sodium-ion batteries with high rate capability and stability

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Journal of Materials Science & Technology 2024年第5期172卷 185-195页

作者： Liuyang Zhang Bicheng Zhu Difa Xu Zibao Qian Ping Xie Tao Liu Jiaguo Yu laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Hunan Key laboratory of applied Environmental Photocatalysis Changsha UniversityChangsha 410022China State Key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Sodium-ion batteries are promising candidates for large-scale grid storage systems and other applications.Their foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion batteries.It is still challenging to explore desirable anode material.In this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and selenisation.The FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the heterostructure.Moreover,it delivers high performance(510 mAh g^(-1)at 0.2 A g^(-1)),superior rate capa-bility(90%retention at 5 A g^(-1)),and good long-time cycling stability(78%capacity retention after 1800 cycles at a high current density of 2 A g^(-1)).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent performance.Namely,a ca-pacity of 272 mAh g^(-1)(at 1 A g^(-1))within the operating voltage from 1 to 3.8 V can be obtained.This work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.

关键词： Cobalt-iron selenide Heterojunctions Sodium storage Anode material Full battery

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Multiscale control of MnO2 growth via [WO6]-perturbed[MnO6] assembly toward a favorable balance between capacitance and rate performance

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Rare Metals 2024年第4期43卷 1658-1671页

作者： Jin-Kang Liu Tian-Shuo Yang Zhi-Bin Ren Adekunle-Adedapo Obisanya Xin-Yi Tan Yan-Di Rao Jun-Shuang Zhou Fa-Ming Gao Jian-Ren Wang Hebei Key laboratory of applied Chemistry Yanshan University

Although pseudocapacitive manganese dioxide（MnO2） integrates the high-power merit of carbonaceous materials with the high-energy merit of battery-type materials,it still has a long way to go in achieving a more satisfactory balance of higher energy and power density,and in decoupling the relationship of structural characteristics with energy storage performance.To realize such goals,a bottom-up [WO6]-perturbed [MnO6] assembly strategy has been developed here due to their similar structure,yet mismatched lattice parameters.This facile protocol is capable of finely controlling the morphology and crystal structure of MnO2by adjusting its internal[WO6] concentration.Therefore,the as-prepared WxMnO2is treated as an ideal platform to scrutinize the correlations of the structure with the energy storage performance.The operando Raman spectra and finite element analysis have fully demonstrated the superiority of the locally ordered defects-enriched structure of W0.02-MnO2,which could reach a favorable balance between the ion diffusion equilibrium time and the number of active sites.As a result,the W0.02-MnO2is able to deliver a high capacitance of 292 F·g-1at a current density of 1 A·g-1and a remarkable rate performance with a 60% capacity retention at a current density of 50 A·g-1.The further unveiled structure-performance relationship provides a guideline for the design of better pseudocapacitive energy storage devices.

关键词： Supercapacitors Pseudocapacitive materials MnO 2 Tungsten doping Crystal structure regulation

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Introducing urea into tirapazamine derivatives to enhance anticancer therapy

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National Science Review 2024年第4期11卷 245-253页

作者： Yajun Xu Jianlin Lv Chaoying Kong Ya Liu Kun Wang Zhaohui Tang Xuesi Chen Key laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of applied Chemistry and Engineering University of Science and Technology of China

Tirapazamine（TPZ） has been approved for multiple clinical trials relying on its excellent anticancer potential.However,as a typical hypoxia-activated prodrug（HAP）,TPZ did not exhibit survival advantages in Phase Ⅲ clinical trials when used in combination therapy due to the insufficient hypoxia levels in patients' tumors.In this study,to improve the therapeutic effects of TPZ,we first introduced urea to synthesize a series of urea-containing derivatives of TPZ.All urea-containing TPZ derivatives showed increased hypoxic cytotoxicity（9.51-30.85-fold） compared with TPZ,while maintaining hypoxic selectivity.TPZP,one of these derivatives,showed 20-fold higher cytotoxicity than TPZ while maintaining a similar hypoxic cytotoxicity ratio.To highly efficiently deliver TPZP to the tumors and reduce its side effects on healthy tissues,we further prepared TPZP into a nanodrug with fibrin-targeting ability:FT11-TPZP-NPs.CA4-NPs,a vascular disrupting agent,was used to increase the fibrin level within tumors and exacerbate tumor hypoxia.By being combined with CA4-NPs,FT11-TPZP-NPs can accumulate in the hypoxia-aggravated tumors and activate sufficiently to kill tumor cells.After a single-dose treatment,FT11-TPZP-NPs+CA4-NPs showed a high inhibition rate of 98.1% against CT26 tumor models with an initial volume of ～480 mm3and four out of six tumors were completely eliminated;it thereby exerted a significant antitumor effect.This study provides a new strategy for improving the therapeutic effect of TPZ and other HAPs in anticancer therapy.

关键词： tirapazamine vascular disrupting agent hypoxia-activated prodrug combretastatin A4 urea

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Modularized viromimetic polymer nanoparticle vaccines(VPNVaxs) to elicit durable and effective humoral immune responses

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National Science Review 2024年第3期11卷 200-214页

作者： Zichao Huang Xinyu Zhuang Liping Liu Jiayu Zhao Sheng Ma Xinghui Si Zhenyi Zhu Fan Wu Ningyi Jin Mingyao Tian Wantong Song Xuesi Chen Key laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences School of applied Chemistry and Engineering University of Science and Technology of China Changchun Veterinary Research Institute Chinese Academy of Agricultural Sciences Jilin Biomedical Polymers Engineering laboratory State Key laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Virus-like particle(VLP) vaccines had shown great potential during the COVID-19 pandemic, and was thought to be the next generation of antiviral vaccine technology due to viromimetic structures. However,the time-consuming and complicated processes in establishing a current recombinant-protein–based VLP vaccine has limited its quick launch to the out-bursting pandemic. To simplify and optimize VLP vaccine design, we herein report a kind of viromimetic polymer nanoparticle vaccine(VPNVax), with subunit receptor-binding domain(RBD) proteins conjugated to the surface of polyethylene glycol-b-polylactic acid(PEG-b-PLA) nanoparticles for vaccination against SARS-CoV-2. The preparation of VPNVax based on synthetic polymer particle and chemical post-conjugation makes it possible to rapidly replace the antigens and construct matched vaccines at the emergence of different viruses. Using this modular preparation system, we identified that VPNVax with surface protein coverage of 20%–25% had the best immunostimulatory activity, which could keep high levels of specific antibody titers over 5 months and induce virus neutralizing activity when combined with an aluminum adjuvant. Moreover, the polymer nano-vectors could be armed with more immune-adjuvant functions by loading immunostimulant agents or chemical chirality design. This VPNVax platform provides a novel kind of rapidly producing and efficient vaccine against different variants of SARS-CoV-2 as well as other viral pandemics.

关键词： vaccine polymer nanomaterials SARS-CoV-2

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