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Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年

作者： Yan YE Lei ZHANG Can CHEN Shan CHANG Yuhao YI Qinglai feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) Department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of natural Resources Chengdu University of Technology Second Geological Brigade of Hubei Geological Bureau College of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. Yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in South China, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, South China show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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Constructing quasi-2D perovskite to collect hot carriers to reduce open-circuit voltage loss for efficient inverted perovskite solar cells

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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu Yang feng Chunming Yang Lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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AsyCo: an asymmetric dual-task co-training model for partial-label learning

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Science China(Information Sciences) 2025年

作者： Beibei LI Yiyuan ZHENG Beihong JIN Tao XIANG Haobo WANG Lei feng College of Computer Science Chongqing University State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences University of Chinese Academy of Sciences School of Software Technology Zhejiang University School of Computer Science and Engineering Nanyang Technological University

Partial-label learning (PLL) is a typical problem of weakly supervised learning, where each training instance is annotated with a set of candidate labels. Self-training PLL models achieve state-of-the-art performance but suffer from error accumulation problems caused by mistakenly disambiguated instances. Although co-training can alleviate this issue by training two networks simultaneously and allowing them to interact with each other, most existing co-training methods train two structurally identical networks with the same task, i.e., are symmetric, rendering it insufficient for them to correct each other due to their similar limitations. Therefore, in this paper, we propose an asymmetric dual-task co-training PLL model called AsyCo,which forces its two networks, i.e., a disambiguation network and an auxiliary network, to learn from different views explicitly by optimizing distinct tasks. Specifically, the disambiguation network is trained with a self-training PLL task to learn label confidence, while the auxiliary network is trained in a supervised learning paradigm to learn from the noisy pairwise similarity labels that are constructed according to the learned label confidence. Finally, the error accumulation problem is mitigated via information distillation and confidence refinement. Extensive experiments on both uniform and instance-dependent partially labeled datasets demonstrate the effectiveness of AsyCo.

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Isospin-conserving hadronic decay of the D_(s1)(2460) into D_(s)π^(+)π^(-)

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Communications in Theoretical Physics 2023年第5期75卷 119-127页

作者： Meng-na Tang Yong-hui Lin feng-Kun Guo Christoph Hanhart Ulf-G.Meißner CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics Universität BonnD-53115 BonnGermany Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Institute for Advanced Simulation and Institut für Kernphysik Forschungszentrum JülichD-52425 JülichGermany Tbilisi State University 0186 TbilisiGeorgia

The internal structure of the charm-strange mesons D_(s0)^(*)(2317)and D_(s1)(2460)are the subject of intensive *** widths are small because they decay dominantly through isospinbreaking hadronic channels D_(s0)^(*)(2317)^(+)→D_(s)^(+)π^(0) and D _(s1)(2460)^(+)→D_(s)^(*+)π^(0).The D_(s1)(2460)can also decay into the hadronic final states D_(s)^(+)ππ,conserving *** that case there is,however,a strong suppression from phase *** study the transition D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)in the scenario that the D_(s1)(2460)is a D^(*)K hadronic *** ππ final state interaction is taken into account through dispersion *** find that the ratio of the partial widths of the Γ(D_(s1)(2460)^(+)→D_(s)^(+)π^(+)π^(-)) / Γ(D_(s1)(2460)^(+)→D_(s)^(*+)π^(0))obtained in the molecular picture is consistent with the existing experimental *** interestingly,we demonstrate that theπ+π−invariant mass distribution shows a double bump structure,which can be used to disentangle the hadronic molecular picture from the compact state picture for the D_(s1)(2460)^(+).Predictions on the B_(s1)^(0)→B_(s)^(0)π^(+)π^(-)are also made.

关键词： hadronic molecule isospin symmetry heavy quark flavor symmetry

Schemes for Generating Different Nonlinear Schrodinger Integrable Equations and Their Some Properties

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 579-600页

作者： Yu-feng ZHANG Hai-feng WANG na BAI School of Mathematics China University of Mining and TechnologyXuzhou 221116China School of Computer Science and Technology China University of Mining and TechnologyXuzhou 221116China

In the paper,we want to derive a few of nonlinear Schrodinger equations with various formats and investigate their properties,such as symmetries,single soliton solutions,multi-soliton solutions,and so *** of all,we propose an efficient and straightforward scheme for generating nonisospectral integrable hierarchies of evolution equations for which a generalized nonisospectral integrable Schrodinger hierarchy(briefly GNISH)singles out,from which we get a derivative nonlinear Schrodinger equation,a generalized nonlocal Schrodinger integrable system and furthermore we investigate the symmetries and conserved qualities of the ***,we apply the dbar method to obtain a generalized nonlinear Schr?dinger-Maxwell-Bloch(GNLS-MB)equation and its hierarchy by introducing a generalized Zakhrov-Shabat spectral problem,whose soliton solutions and gauge transformations are obtained.

关键词： nonisospectral integrable hierarchy Schroodinger equation symmetry

Hepatocellular carcinoma after ablation:The imaging follow-up scheme

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World Journal of Gastroenterology 2013年第6期19卷 797-801页

作者： Lin-na Liu hui-Xiong Xu Yi-feng Zhang Jun-Mei Xu Department of Medical Ultrasound Shanghai Tenth People's Hospital Tenth People's Hospital of Tongji University

Percutaneous ablation using thermal or chemical methods has been widely used in the treatment of hepatocellular carcinoma (HCC).Nowadays,contrast-enhanced imaging modalities such as computed tomography (CT),magnetic resonance imaging (MRI),and contrast-enhanced ultrasound (CEUS) are widely used to evaluate local treatment response after ablation *** is gaining increasing attention due to its characteristics including real-time scanning,easy performance,lack of radiation,wide availability,and lack of allergy *** studies have documented that CEUS is comparable to CT or MRI in evaluating local treatment efficacy within 1 mo of ***,little information is available regarding the role of CEUS in the followup assessment after first successful ablation *** et al found that in comparison with contrastenhanced computed tomography (CECT),the sensitivity,specificity,positive predictive value,negative predictive value and overall accuracy of CEUS in detecting local tumor progression (LTP) were 67.5%,97.4%,81.8%,94.4% and 92.3%,respectively,and were 77.7%,92.0%,92.4%,76.7% and 84.0%,respectively for the detection of new intrahepatic *** concluded that the sensitivity of CEUS in detecting LTP and new intrahepatic recurrence after ablation is relatively low in comparison with CECT,and CEUS cannot replace CECT in the follow-up assessment after percutaneous ablation for *** results are meaningful and instructive,and indicated that in the follow-up period,the use of CEUS alone is not *** this commentary,we discuss the discordance between CT and CEUS,as well as the underlying mechanisms *** propose the combined use of CT and CEUS which will reduce false positive and negative results in both *** also discuss future issues,such as an evidence-based ideal imaging follow-up scheme,and a cost-effectiveness analysis of this imaging follow-up scheme.

关键词： Hepatocellular carcinoma Radiofrequency ablation Ethanol ablation Contrast-enhanced ultrasound Follow-up Treatment response Computed tomography

A Zone Plate as a Tunable Terahertz Filter

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Chinese Physics Letters 2010年第6期27卷 97-99页

作者： feng hui WANG Li Laboratory of Optical Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190

A broadband tunable terahertz filter based on a zone plate is demonstrated in our terahertz time domain spec- trometer. The central bandpass frequency covers the whole spectral range of the terahertz wave emitted from a ZnTe emitter, from 0.5 THz to 2.5 THz, and can be tuned continuously by simply moving the zone plate along the terahertz beam path. The peak transmission is about 40% and the bandwidth varies from 0.16 THz to 0.25 THz at different bandpass frequencies when the aperture size is kept constant.

关键词： Zoning A Zone Plate Tunable Terabertz Filter

In situ formed three-dimensional (3D) lithium-boron(Li-B) alloy as a potential anode for next-generation lithium batteries

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Rare Metals 2021年第12期40卷 3494-3500页

作者： Hai-feng Huang Yi-na Gui Fu Sun Zhi-Jian Liu hui-Long Ning Chen Wu Li-Bao Chen State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China

The practical application of the lithium anode in lithium metal batteries(LMBs) has been hindered by the uncontrollable growth of lithium dendrite and the high volumetric change during cycling. Herein, the in situ formed three-dimensional(3D) lithium-boron(Li-B) alloy is suggested as an excellent alternative to the Li metal, in which the 3D Li B skeleton can mitigate the growth of Li dendrites and volumetric change. In this study, the Li-B alloy anodes with different B contents were manufactured by high-temperature melting. It was found that the boron content had a significant effect on the electrochemical performance of the Li-B alloy. The Li-B alloy with the least B content(10 wt%, 10LiB) demonstrated the lowest overpotential of 0.0852 V after 300 h and the lowest interface resistance. However, the full cell with 15LiB as the anode displayed the best cycling performance of 115 m Ah·g^(-1) after 100 cycles with a columbic efficiency greater than 97%. The obtained results suggest that the in situ formed three-dimensional Li-B alloy anode can be an excellent alternative to the Li anode via tuning B contents for next-generation high energy density LMBs.

关键词： Li-B alloy 3D skeleton Solid electrolyte interface(SEI) Anode Lithium metal battery

负载黑米花色苷的纳米颗粒对Caco-2细胞损伤的保护作用

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食品科学 2025年第3期46卷 102-109页

作者：刘雅琪周娜冯蒙蒙艾欣赵磊赵亮北京工商大学老年营养与健康教育部重点实验室北京市食品添加剂工程技术研究中心北京100048 菏泽职业学院山东菏泽274002

为提高黑米花色苷(black rice anthocyanins,BRA)的稳定性和生物活性,本研究利用牛血清白蛋白(bovine serum albumin,BSA)和京尼平(genipin,GP)制备负载BRA的纳米颗粒(BRA-BSAGP),并分析BSAGP与BRA的相互作用,探究BRA-BSAGP在模拟胃肠道消化环境中的释放特性,以及对葡聚糖硫酸钠(dextran sulfate sodium,DSS)诱导Caco-2细胞损伤的改善效果及作用机制。结果表明,BRA-BSA_(GP)形态呈较均一的球形,其BRA包埋率为(81.10±0.08)%;傅里叶变换红外光谱和X射线衍射分析结果显示,BRA被成功包埋在BSA中。体外胃肠道释放实验证实BRA-BSA_(GP)纳米颗粒能够有效减缓BRA的释放,在模拟空腹和进食状态下最终释放量仅分别为22.51%和20.10%。细胞实验结果表明,BRA-BSAGP显著提高了DSS诱导损伤的Caco-2细胞的存活率,并增加了紧密连接蛋白(Claudin-1、Occludin和ZO-1)的表达水平。本研究结果可为BRA的应用和开发缓解溃疡性结肠炎损伤的功能性食品提供理论依据。

关键词：黑米花色苷牛血清白蛋白京尼平 Caco-2细胞