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New Benthic Fossils from the Late Ediacaran Strata of Southwestern China

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 311-323页

作者： liU Junping li Ming tang Feng ZHAO Jiangtai SONG Sicun zhou Ying SONG Xiaohan REN liudong School of Earth Science and Resources China University of GeosciencesBeijing 10083China Yunnan Institute of Geological Survey Kunming 650216China Chinese Academy of Geological Sciences Beijing 10037China Key Laboratory for Stratigraphy and Paleontology MNRCBeijing 10037China School of Earth Science and Engineering Nanjing UniversityNanjing 210093China Department of Earth Sciences University College LondonLondon WC1E 6BTU.K. CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdaoShandong 266071China Institute of Geology Chinese Academy of Geological SciencesBeijing 10037China

The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,China,is marked by copious macrofossils at the apex of the Ediacaran *** fauna features benthic algae with varied holdfasts and other fossils of indeterminate taxonomic affinity and is compositionally unique compared to the Shibantan and Gaojiashan biotas of the Dengying *** the Miaohe and Wenghui biotas of the Doushantuo Fm.,elsewhere in *** novel benthic saccular macroalgal fossil,named here Houjiashania yuxiensis *** ***.,from the Jiangchuan Biota is based on fossils that are sausage-shaped,elongate,tubular,ranging from 0.3 to 4 cm in length,and up to 0.8 cm in *** terminus is blunt and rounded to an obtuse angle,the other is bent with a spread-out surface resembling a holdfast,suggesting a three-dimensional ***,stipe-shaped outgrowths,likely vestiges of sessile saccular life forms,are prevalent in macroalgal fossils of analogous size and shape,as well as present brown algae Scytosiphonaceae,such as Colpomenia and *** new findings augment the diversity of benthic algae,such as those known from the Early Neoproterozoic Longfengshan Biota in North *** benthic algal macrofossils in the Jiucheng *** to knowledge of Late Ediacaran metaphyte diversification and offer more clues about the evolutionary positioning of primitive *** co-occurrence of numerous planktonic and benthic multicellular algae and planktonic microbes might have facilitated ecologically the more extensive later Cambrian explosion evidenced by the Chengjiang Biota in Yunnan.

关键词： paleophytology benthic saccular algae algal evolution Neoproterozoic Jiucheng Member Jiangchuan Biota Yunnan Province

Characteristics and genesis of shoal facies reservoir of the Lower Ordovician Tongzi Formation in southeastern Sichuan Basin,China

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Petroleum 2024年第3期10卷 427-439页

作者： Ruiqing Tao Hao tang Wei Yan Yading li Qianwen Mo ling li li zhou Tao Ma Jinbiao An Guoliang Xiao Xiucheng Tan Southwest Petroleum University Division of Key Laboratory of Carbonate ReservoirsCNPCChengdu610500China Research Institute of Exploration and Development PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Exploration Division PetroChina Southwest Oil and Gas Field CompanyChengdu610051China College of Geosciences China University of Petroleum(Beijing)Beijing102200China Chuanzhong Oil and Gas Geological Research Institute PetroChina Southwest Oil and Gas Field CompanySuining629000China

The Lower Ordovician Tongzi Formation containing abundant shoal sediments is the most promising stratum for the petroleum exploration in the Sichuan ***,the current studies mainly focus on the central part of the Basin,the systematic analysis of the southeastern part with well-developed shoal facies is *** paper aims to clarify the characteristics and genesis of the Tongzi Formation reservoir in Southeastern Sichuan Basin,following an analysis of sedimentary facies within the sequence stratigraphic *** research shows that the main types of reservoir rocks are oolitic,intraclastic and bioclastic *** the reservoir spaces consist mainly of intergranular(dissolved)pores,intercrystalline(dissolved)pores,intragranular dissolved pores and *** them,intergranular pores account for the highest proportion,which is followed by intragranular dissolved *** addition,most throats are necking and flaky which mainly connect intergranular and intercrystalline pores,*** diagenetic sequence shows that penecontemporaneous karst well improved the porosity of the reservoir in the early-stage although the cementation and compaction reduced parts of *** reservoir formation is associated with the tectonic-depositional settings,diageneses and terrigenous *** and submerged uplifts,forming in the early Ordovician amalgamation between Yangtze and Cathaysia blocks,accumulated shoal sediments as the material basis for the reservoir *** karst forming intragranular dissolved pores and the dolomitization aiding grainstones to resist the pressure solution are the key to increasing porosity and preserving *** absence of terrigenous contamination prevented intergranular pores from being strongly cemented,which resulted in the reservoir difference between the central and southeastern Sichuan *** study can be used as a reference for the further exploration of Ordovician

关键词： Reservoir characteristics Reservoir genesis Tongzi formation Lower ordovician Southeastern Sichuan Basin

User Churn Prediction Hierarchical Model Based on Graph Attention Convolutional Neural Networks

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China Communications 2024年第7期21卷 169-185页

作者： Mei Miao tang Miao zhou Long School of Economics and Management Beijing Jiaotong UniversityBeijing 100044China School of Automotive and Rail Transit Nanjing Institute of TechnologyNanjing 211167China Nanjing Intelligent Aviation Research Institute Co. LtdNanjing 210014China

The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among *** the same time,users'consumption preferences and choices are *** churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new *** conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various ***,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic *** prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same *** work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned *** main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud ***,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages ***,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and *** summary,the churn

关键词： cloud-edge cooperative framework GAT-CNN self-attention and graph convolution models subscriber churn prediction

Epigenetic regulators as the foundation for molecular classification of colorectal cancer

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Cancer Biology & Medicine 2024年第7期21卷 547-552页

作者： Zhenyu liu Xin zhou Fuchou tang School of life Sciences Biomedical Pioneering Innovation CenterDepartment of General SurgeryThird HospitalPeking UniversityBejing 100871China Bejing Advanced Innovation Center for Genomics(ICG) Ministry of Education Key Laboratory of Cell Proliferation and DifferentiationBeijing 100871China Peking University Third Hospital Cancer Center Bejing 100191China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100871China

Colorectal cancer (CRC) accounts for approximately 10% of newly diagnosed cancer cases and cancer-related deaths worldwide~1. The identification of molecular subtypes of CRCs has significantly advanced treatment strat... 详细信息

关键词： cancer colorectal cases

Positive definiteness of real quadratic forms resulting from the variable-step L1-type approximations of convolution operators

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Science China Mathematics 2024年第2期67卷 237-252页

作者： Hong-lin liao Tao tang Tao zhou School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Division of Science and Technology BNU-HKBU United International CollegeZhuhai 519087China SUSTech International Center for Mathematics Shenzhen 518055China NCMIS&LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

The positive definiteness of real quadratic forms with convolution structures plays an important rolein stability analysis for time-stepping schemes for nonlocal operators. In this work, we present a novel analysistool to handle discrete convolution kernels resulting from variable-step approximations for convolution *** precisely, for a class of discrete convolution kernels relevant to variable-step L1-type time discretizations, weshow that the associated quadratic form is positive definite under some easy-to-check algebraic conditions. Ourproof is based on an elementary constructing strategy by using the properties of discrete orthogonal convolutionkernels and discrete complementary convolution kernels. To our knowledge, this is the first general result onsimple algebraic conditions for the positive definiteness of variable-step discrete convolution kernels. Using theunified theory, we obtain the stability for some simple nonuniform time-stepping schemes straightforwardly.

关键词： discrete convolution kernels positive definiteness variable time-stepping orthogonal convolution kernels complementary convolution kernels

In situ formed Mg(BH_(4))_(2) for improving hydrolysis properties of MgH_(2)

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Journal of Magnesium and Alloys 2024年第3期12卷 1204-1214页

作者： Yongyang Zhu Mili liu liming Zeng Yin Wang Daifeng Wu Rui li Qing zhou Renheng tang Fangming Xiao Institute of Resources Utilization and Rare Earth Development Guangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510641China

The hydrolysis of MgH_(2) delivers high hydrogen capacity(15.2 wt%),which is very attractive for real-time hydrogen ***,the formation of a surface passivation Mg(OH)_(2) layer and the large excess of H_(2)O required to ensure complete hydrolysis are two key challenges for the MgH_(2) hydrolysis ***,a low-cost method is reported to synthesize MgH_(2)@Mg(BH_(4))_(2) composite via ball-milling MgH_(2) with cheap and widely available B_(2)O_(3)(or B(OH)_(3)).By adding small amounts of B_(2)O_(3),the in-situ formed Mg(BH_(4))_(2) could significantly promote the hydrolysis of MgH_(2).In particular,the MgH_(2)–10 wt%B_(2)O_(3) composite releases 1330.7 mL·g^(−1) H_(2)(close to 80%theoretical hydrogen generation H_(2))in H_(2)O and 1520.4 mL·g^(−1) H_(2)(about 95%)in 0.5 M MgCl_(2) in 60 min at 26℃ with hydrolysis rate of 736.9 mL·g^(−1)·min^(−1) and 960.9 mL·g^(−1)·min^(−1) H_(2) during the first minute of the hydrolysis,*** addition,the MgCl_(2) solution allows repeated use by filtering and exhibits high cycle stability(20 cycles),therefore leading to much reduced capacity loss caused by the excess H_(2)*** show that by introducing B_(2)O_(3) and recycling the 0.5 M MgCl_(2) solution,the system hydrogen capacity can approach 5.9 wt%,providing a promising hydrogen generation scheme to supply hydrogen to the fuel cells.

关键词： Hydrolysis MgH_(2) Mg(BH_(4))_(2) Hydrogen generation B_(2)O_(3) MgCl_(2)

Peroxidase-like nanozyme based microenvironment-responsive injectable hydrogel for bacteria-infected wound healing

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Science China Technological Sciences 2024年第10期67卷 3247-3260页

作者： zhou Wei li XiaNan tang MengCheng PAN lingFeng WANG BeiBei ZHANG Hao ZHANG Han WANG ShiBo KONG XiangDong Institute of Smart Biomaterial Materials School of Materials Science and EngineeringZhejiang University of Science & Technology Zhejiang-Mauritius Joint Research Center for Biomaterials and Tissue Engineering Zhejiang University of Science & Technology

Hydrogel stands out as one of the most attractive wound dressings due to its excellent moisturizing properties and capacity to absorb wound exudates. However, conventional hydrogel dressings often lack responsiveness to the microenvironment, merely acting as protective barriers for the wound. Consequently, they exhibit limited effectiveness in preventing infection and facilitating wound repair. To address these problems, we have developed a multifunctional injectable hydrogel, CF/MS@HG, based on peroxidase-like nanozymes, aiming at rapidly healing bacterial-infected wounds. The hydrogel is mainly composed of oxidized sodium alginate, aminated gelatin, and polylysine, encapsulating MIL-101(CuFe) NPs(CF) and manganese selenide nanoparticles(MnSe2NPs, or MS NPs). After injection, the complex rapidly gelatinizes at the infected wound site through a Schiff base reaction. In vitro experiments have demonstrated the hydrogel's strong adhesion and self-healing ***, CF exhibiting peroxidase(POD)-like activity, catalyzes in situ hydrogen peroxide(H2O2) to generate highly toxic hydroxyl radicals(·OH) within the wound microenvironment, inducing oxidative damage to bacteria. Meanwhile, MS decomposes into H2Se in the slightly acidic wound microenvironment, disrupting bacterial metabolism and inhibiting *** addition of polylysine further enhances the hydrogel's antibacterial properties. In vivo experiments have shown that the hydrogel exhibits excellent biological safety and significantly promotes wound healing. This multifunctional smart hydrogel holds great promise for the treatment of bacterial-infected wounds.

关键词： peroxidase-like nanozyme manganese selenide injectable hydrogel bacterial infection wound healing

Recent advances in heterogeneous hydrosilylation of unsaturated carbon-carbon bonds

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Chinese Chemical Letters 2024年第6期35卷 71-85页

作者： Heng Yang Zhijie zhou Conghui tang Feng Chen School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The hydrosilylation of unsaturated carbon-carbon bonds is one of the most critical reactions in silicone industrial *** homogeneous Speier's catalyst,Karstedt's catalyst,and other noble metal-based catalysts are widely ***,simplifying the separation of the homogeneous catalyst from reaction products and reducing the high cost of precious metals is still *** review describes the recent development of heterogeneous catalysts for alkene,alkyne,and allene hydrosilylations,which can effectively solve problems in homogeneous hydrosilylation.

关键词： Hydrosilylation Heterogeneous catalysis Alkenes Alkynes Silanes

Improved catalytic performance of CO_(2) electrochemical reduction reaction towards ethanol on chlorine-modified Cu-based electrocatalyst

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Nano Research 2024年第5期17卷 3761-3768页

作者： Yifan liu Hehua tang Yitian zhou Bo-lin lin School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Effective electrochemical conversion of CO_(2) to value-added liquid multi-carbon products driven by renewable energy is a promising approach to alleviate excessive CO_(2) emission and achieve large-scale renewable energy ***,the selectivity and catalytic activity towards liquid multi-carbon products of CO_(2) electroreduction reaction are still unsatisfactory due to the sluggish C-C coupling process and the formation of complex oxygen-containing ***,designing and fabricating highly effective electrocatalysts is crucial for practical applications in this ***,we developed Cl-modified Cu catalyst(Cu-Cl)for efficient electrochemical reduction of CO_(2) to *** optimal Faradaic efficiency and partial current density of ethanol on the Cu-Cl sample reached 26.2%and 343.2 mA·cm^(-2) at-0.74 V(*** hydrogen electrode(RHE)),which were 1.66 and 1.76 times higher than those of the catalyst without Cl decoration,outperforming those in most previously reported *** functional theory(DFT)calculations revealed that the Cl-modified Cu surface suppressed the parasitic hydrogen evolution reaction(HER)and reduced the energy barrier for the C-C coupling process,making the formation of key intermediates favorable for ethanol ***,the decoration of Cl on the Cu surface facilitated ethanol formation.

关键词： CO_(2)electrochemical reduction halogen chlorine Cu-based catalysts ethanol multi-carbon products