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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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Structural biology revolution led by technical breakthroughs in cryo-electron microscopy

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Chinese Physics B 2018年第5期27卷 49-58页

作者： chang-cheng Yin Department of Biophysics College of Basic Medicine Peking University Health Science Center Peking University Beijing 100191 China

Recent technical breakthroughs in cryo-electron microscopy（cryo-EM） revolutionized structural biology, which led to the 2017 Nobel Prize in chemistry being awarded to three scientists, Jacques Dubochet, Joachim Frank, and Richard Henderson, who made groundbreaking contributions to the development of cryo-EM. In this review, I will give a comprehensive review of the developmental history of cryo-EM, the technical aspects of the breakthrough in cryo-EM leading to the structural biology revolution, including electron microscopy, image recording devices and image processing algorithms,and the major scientific achievements by Chinese researchers employing cryo-EM, covering protein complexes involved in or related to gene expression and regulation, protein synthesis and degradation, membrane proteins, immunity, and ***, I will give a perspective outlook on the development of cryo-EM in the future.

关键词： cryo-electron microscopy (cryo-EM) structural biology protein molecular machinery

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循环加载与卸围压组合扰动下红砂岩损伤破裂与渗透特性

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岩土工程学报 2025年第1期47卷 48-56页

作者：姚玮俞缙周先齐常方强常旭厦门理工学院土木工程与建筑学院福建厦门361024 华侨大学福建省隧道与城市地下空间工程技术研究中心福建厦门361021

为探究深地工程开挖诱导岩体损伤破裂及渗透性演化规律,开展了同步测定波速与渗透率的循环加载与卸围压组合扰动三轴试验,研究了不同条件下红砂岩的损伤与渗透性演化规律。结果表明:①岩石在不同组合扰动阶段具有不同的应力应变曲线形态... 详细信息

为探究深地工程开挖诱导岩体损伤破裂及渗透性演化规律,开展了同步测定波速与渗透率的循环加载与卸围压组合扰动三轴试验,研究了不同条件下红砂岩的损伤与渗透性演化规律。结果表明:①岩石在不同组合扰动阶段具有不同的应力应变曲线形态,其末端形态取决于在何种扰动阶段破坏,初始应力比为决定组合扰动诱发岩石破坏难易的主要因素;②总峰值轴向应变随初始应力比增大而增大,其中组合扰动轴向应变占比始终较低,总峰值体积应变绝对值随初始应力比增大而先增大后减小,其中组合扰动体积应变占比较高;③在初始加载阶段,波速增大,渗透率降低,在组合扰动阶段,波速下降,渗透率增加,且损伤与体积应变近似呈线性关系,损伤与渗透率随扰动次数增加均呈先慢后快的增长趋势,且拐点分别近似在一条直线上;④岩石在组合扰动卸围压阶段破坏为单剪切破坏模式,在组合扰动循环加载阶段破坏为共轭剪切破坏模式;⑤双高(高初始应力比与高初始围压)条件将显著加剧岩体开挖失稳破坏风险。

关键词：深地工程组合扰动力学特性损伤渗透性

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Synergistic effect of fatty liver and smoking on metabolic syndrome

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World Journal of Gastroenterology 2009年第42期15卷 5334-5339页

作者： po-Hsin Chiang Tsui-Yen chang Jong-Dar Chen Department of Family Medicine Shin Kong Wu Ho-Su Memorial Hospital#95 Wen Chang RoadShih LinTaipei 111TaiwanChina School of Medicine Fu Jen Catholic University#510 Chung Cheng RoadHsinchuangTaipei 242TaiwanChina

AIM:To investigate the association of fatty liver and smoking on metabolic syndrome and its ***:This cross-sectional study enrolled participants who attended annual health screening at Shin Kong Wu Ho-Su Memorial Hospital from January to December 2005.A total of 3455(1981 men and 1474 women) subjects were included in final *** liver was diagnosed using abdominal ultrasonography by trained *** modified National Cholesterol Education Program Adult Treatment Panel Ⅲ was used to define metabolic *** associations between smoking,fatty liver and metabolic syndrome were analyzed using multiple logistic ***:Subjects with fatty liver,and who smoked tobacco,had the highest odds ratios(ORs) for high waist circumference [OR,4.5(95% CI:3.3-6.1) ,P poprotein cholesterol(HDL-C) [OR,8.3(95% CI:6.1-11.3) ,P ponents,especially for hypertriglyceridemia and low serum HDL-C.

关键词： Smoking Fatty liver Synergistic effect Metabolic syndrome

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基于双车接触点响应残差的桥梁模态参数识别方法研究

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工程力学 2025年第1期42卷 199-208页

作者：陈诚张静杜昌骏杨栋贺文宇合肥工业大学土木与水利工程学院合肥230009 广州大学工程抗震研究中心广州510006 工程抗震减震与结构安全教育部重点实验室广州510006

针对“车辆扫描法”在桥梁模态参数识别过程中存在对路面粗糙度和车辆速度过于敏感等问题，提出一种新的基于接触点响应的车辆扫描法识别桥梁模态参数(频率和振型)。在考虑相位差的前提下对两车的接触点响应作差，利用该残差识别结构各... 详细信息

针对“车辆扫描法”在桥梁模态参数识别过程中存在对路面粗糙度和车辆速度过于敏感等问题，提出一种新的基于接触点响应的车辆扫描法识别桥梁模态参数(频率和振型)。在考虑相位差的前提下对两车的接触点响应作差，利用该残差识别结构各阶模态频率以及对应的模态振型;给出了基于双车接触点响应残差进行桥梁模态参数识别的流程，通过数值算例验证了其可行性，并系统讨论了车辆速度、质量以及路面粗糙度等因素对识别结果的影响。数值结果表明：该文所提出的方法简单有效，能够在有效剔除路面粗糙度影响的前提下准确识别桥梁结构的模态参数。

关键词：桥梁工程模态参数识别接触点响应车-桥耦合振动路面粗糙度

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Code Transform Model Producing High-Performance Program

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Computer Modeling in Engineering & Sciences 2021年第10期129卷 253-277页

作者： Bao Rong chang Hsiu-Fen Tsai po-Wen Su Department of Computer Science and Information Engineering National University of KaohsiungKaohsiungTaiwan Department of Fragrance and Cosmetic Science Kaohsiung Medical UniversityKaohsiungTaiwan

This paper introduces a novel transform method to produce the newly generated programs through code transform model called the second generation of Generative Pre-trained Transformer(GPT-2)reasonably,improving the program execution performance ***,a theoretical estimation in statistics has given the minimum number of generated programs as required,which guarantees to find the best one within *** proposed approach can help the voice assistant machine resolve the problem of inefficient execution of application *** addition to GPT-2,this study develops the variational Simhash algorithm to check the code similarity between sample program and newly generated program,and conceives the piecewise longest common subsequence algorithm to examine the execution’s conformity from the two programs mentioned *** code similarity check deducts the redundant generated programs,and the output conformity check finds the best-performing generative *** addition to texts,the proposed approach can also prove the other media,including images,sounds,and *** a result,the newly generated program outperforms the sample program significantly because the number of code lines reduces 27.21%,and the program execution time shortens 24.62%.

关键词： Newly generated programs GPT-2 predetermined generative programs variational Simhash algorithm piecewise longest common subsequence

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Matched glass-to-Kovar seals in N_2 and Ar atmospheres

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 874-882页

作者： cheng-hsien Kuo Pi-ying cheng chang-pin Chou Department of Mechanical Engineering Chiao Tung University

The oxidation of Kovar alloy was investigated, the wetting and spreading behavior of hard and soft glasses on Kovar alloy were studed by using the sessile drop method, and the quality and the seal strength of glass-Kovar seals were tested. The experimental results indicated that the preoxidation of Kovar alloy for approximately 10 min at 700℃ in air resulted in excellent adherence in glass-Kovar seals. The wetting and spreading behavior of glass on preoxidized Kovar alloy were superior to that on nonoxidized Kovar alloy. The wetting ability of ASF110 glass, at 950℃ and 980℃ in Ar and N2 atmospheres, was significantly superior to that of ASF200R and ASF700 glasses. The seal quality of the glass-preoxidized Kovar seal was superior to that of the glass-nonoxidized Kovar seal. The shear strength of the ASFll0 glass-preoxidized Kovar seal, which was prepared at 980℃ for 20 min in an Ar atmosphere, was approximately 3.9 MPa.

关键词： Kovar alloy glass sealing argon nitrogen oxidation wetting

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IMAGE SEGMENTATION BY PIECEWISE CONSTANT MUMFORD-SHAH MODEL WITHOUT ESTIMATING THE CONSTANTS

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Journal of Computational Mathematics 2006年第3期24卷 435-443页

作者： Xue-cheng Tai chang-hui Yao CIPR Department of Mathematics University of Bergen Norway Department of Mathematics University of Bergen Norway

In this work, we try to use the so-called Piecewise Constant Level Set Method （PCLSM） for the Mumford-Shah segmentation model. For image segmentation, the Mumford-Shah model needs to find the regions and the constant values inside the regions for the segmen- tation. In order to use PCLSM for this purpose, we need to solve a minimization problem using the level set function and the constant values as minimization variables. In this work, we test on a model such that we only need to minimize with respect to the level set function, i.e., we do not need to minimize with respect to the constant values. Gradient descent method and Newton method are used to solve the Euler-Lagrange equation for the minimization problem. Numerical experiments are given to show the efficiency and advantages of the new model and algorithms.

关键词： PCLSM Image Segmentation Mumford-Shah model.

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Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

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D-DeepoCSORT: multi-object tracking algorithm based on LiDAR and monocular camera

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Optoelectronics Letters 2025年

作者： HE Xiao REN Shuai LIU chang SHI Lei School of Information Engineering， chang'an University School of Control of Robotic and Autonomous Systems， University of California Berkeley

Multi-object tracking is a fundamental problem in computer vision， and DeepoCSORT， due to its reliance on the 2D image position information of targets， tends to exhibit prediction drift. To enhance the tracking stability of DeepoCSORT， this paper proposes a novel multi-sensor data fusion-based multi-object tracking method. Specifically， we build upon the DeepoCSORT foundation and additionally integrate target velocity information directly measured by LiDAR. The introduction of this velocity information is conducted from three perspectives: firstly， during data association， a penalty term is constructed based on the differences in target velocities to constrain generating matches with consistent velocities; secondly， using LiDAR velocity for initialization and online updating of the velocity state within the tracker， making tracking predictions more stable; thirdly， controlling the degree of dependence on velocity information by adjusting the process noise covariance matrix. Evaluation results on the KITTI dataset demonstrate that compared to the original DeepoCSORT， the proposed improved multi-source heterogeneous information fusion method significantly enhances tracking performance， with maximum improvements of 3.35， 3.26， and 3.71 on the HOTA， MOTA， and IDF1 metrics， respectively. This study provides an effective approach to building a more stable and accurate multi-object tracking system.

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