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Characteristics of Paleontological Communities in Surface Sediments of the Southern South China Sea and Their Paleoclimatic and Paleoenvironmental Significance

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Journal of Earth Science 2024年第1期35卷 144-154页

作者： Jing Zhao Li Zhang Xiaoyan Wang Jinglian Ge Min Xu Wei Chen mao luo Qianyong Liang Qiuhua Yu Shuaibing luo Wenkun Qie Key Laboratory of Marine Mineral Resoures Ministry of Natural ResourcesGuangzhou Marine Geological SurveyChina Geological SurveyGuangzhou 511458China National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Understanding the spatial and temporal distribution of different paleontological communities in the southern South China Sea(SCS)is fundamental to explore its paleoclimatic and paleoenvironmental changes.In this study,foraminifera,pollen and diatoms from 100 surface sediment samples covering 40000 km^(2) of sea floor in the southern SCS were comprehensively investigated in terms of their assemblage and distribution.The results showed the existence of abundant foraminifera and pollen in most of the samples,although diatom communities were relatively scarce.Foraminifera were dominated by G.sacculifer,G.menardii,G.ruber,while diatoms were characterized by T.simonsenii,T.nitzschioides and T.longissima,indicating a typical tropical marine environment.The pollen assemblages showed a better reflection of montane rainforest,tropical rainforest and mangrove.The spatial differences among foraminifera assemblages may indicate the effect of water depth and a warmer environment in the southeast part of the study area,while the spatial patterns of diatom and pollen assemblages imply the influence of coastal current.Our study also noted that the compositions of paleontological communities in the SCS can vary significantly in a short distance,and synthesized studies on multiple biological groups are needed to reconstruct the Quaternary climate and the oceanographic environment.

关键词： southern South China Sea sediments foraminifera diatom pollen

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Permian integrative stratigraphy,biotas,paleogeographical and paleoclimatic evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1107-1151页

作者： Shuzhong SHEN Yichun ZHANG Dongxun YUAN Haipeng XU Qi JU Hua ZHANG Quanfeng ZHENG mao luo Zhangshuai HOU State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Nanjing 210049China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China

The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical changes.The supercontinent Pangea was formed to its maximum during this interval,hampering a global east-to-west trending equatorial warm ocean current.Meanwhile,a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea,and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic transition.Stratigraphy and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan Plateau.Widely distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics,reflecting these blocks’different paleolatitude settings and drifting histories.The Himalaya Tethys Zone south to the Yarlung Zangbo suture zone,located in the northern Gondwanan margin,yields fossil assemblages characterized by cold-water organisms throughout the Permian,and was affliated to those of the Gondwanaland.Most of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian(Middle Permian)to Early Triassic in age.These exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions,suggesting that they most probably represent seamount deposits in the Neo-Tethys Ocean.During the Asselian to Sakmarian(Cisuralian,also Early Permian),the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian,and contained typical Gondwana-type cold-water faunas.By the middle Cisuralian(~290-280 Ma),the Cimmerian microcontinents rifted off from the Gondwanaland,and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian Plate.Two slices of microcontinents are discerned as a result of such all

关键词： Permian Tethys Ocean Qinghai-Tibetan Plateau Biotas Paleogeography

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Paleontology Knowledge Graph for Data-Driven Discovery

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Journal of Earth Science 2024年第3期35卷 1024-1034页

作者： Yiying Deng Sicun Song Junxuan Fan mao luo Le Yao Shaochun Dong Yukun Shi Linna Zhang Yue Wang Haipeng Xu Huiqing Xu Yingying Zhao Zhaohui Pan Zhangshuai Hou Xiaoming Li Boheng Shen Xinran Chen Shuhan Zhang Xuejin Wu Lida Xing Qingqing Liang Enze Wang School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Centre for Research and Education on Biological Evolution and Environment Nanjing UniversityNanjing 210023China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China School of the Earth Sciences and Resources China University of GeosciencesBeijing 100083China

A knowledge graph(KG)is a knowledge base that integrates and represents data based on a graph-structured data model or topology.Geoscientists have made efforts to construct geosciencerelated KGs to overcome semantic heterogeneity and facilitate knowledge representation,data integration,and text analysis.However,there is currently no comprehensive paleontology KG or data-driven discovery based on it.In this study,we constructed a two-layer model to represent the ordinal hierarchical structure of the paleontology KG following a top-down construction process.An ontology containing 19365 concepts has been defined up to 2023.On this basis,we derived the synonymy list based on the paleontology KG and designed corresponding online functions in the OneStratigraphy database to showcase the use of the KG in paleontological research.

关键词： paleontology knowledge graph ontology synonymy list OneStratigraphy big data ge-ology.

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重大传染病疫情下基于服务水平的疫苗分配及储备研究

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管理工程学报 2024年第2期38卷 232-242页

作者：冯春蒋雪周鑫昕罗茂西南交通大学交通运输与物流学院四川成都610031

为缓解重大传染病疫情下疫苗的短缺现状,本文结合传染病模型(susceptible-infected-recovered-deceased,SIRD)考虑疫苗需求与疫区医院收治容量的关系,以期望短缺数最小为目标建立疫苗分配模型,推导分析了最佳服务水平和储备量,并给出了... 详细信息

为缓解重大传染病疫情下疫苗的短缺现状,本文结合传染病模型(susceptible-infected-recovered-deceased,SIRD)考虑疫苗需求与疫区医院收治容量的关系,以期望短缺数最小为目标建立疫苗分配模型,推导分析了最佳服务水平和储备量,并给出了不同情形下疫苗的最优分配方案。此外,通过数值模拟,进一步探究了紧急调配成本、资金预算、需求变化、疫区数量以及疫区间相关性等外生变量带来的影响,验证了模型推导结果,为疫苗分配和储备策略提供了科学依据。研究发现:疫苗接种有助于促进病毒感染曲线平坦化和降低疫情峰值,从而减轻医疗系统超负荷运转的现象,降低因感染而死亡的人数;在不考虑储备疫苗的情况下,无论需求的不确定性程度如何,为每个地区提供同等的服务水平有利于最小化疫苗期望短缺量;考虑储备疫苗的情况下,向需求波动幅度较大的疫区提供更高的服务水平可以减少期望短缺,但疫区数量较多时,为每个疫区提供同等服务水平更具公平性,即使会导致疫苗的次优覆盖;是否考虑储备疫苗取决于紧急调配成本、预算的高低以及疫区需求情况等。

关键词：重大传染病需求不确定疫苗分配服务水平 SIRD模型

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黎曼流形上的粒子群运动模型

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四川大学学报（自然科学版） 2024年第3期61卷 62-68页

作者：唐伦潇蔚涛罗懋康四川大学数学学院成都610064

自然界中生物群的协同运动模式多种多样,运动空间的复杂性对该多样性起着关键作用.为描述生物群的协调运动,人们基于欧氏空间提出了多种粒子群运动模型.然而,这些模型往往只能描述简单的运动模式.本文基于Morse势和黎曼流形提出了一个... 详细信息

自然界中生物群的协同运动模式多种多样,运动空间的复杂性对该多样性起着关键作用.为描述生物群的协调运动,人们基于欧氏空间提出了多种粒子群运动模型.然而,这些模型往往只能描述简单的运动模式.本文基于Morse势和黎曼流形提出了一个新模型,该模型可以描述任意运动空间中的群体运动,且易于工程实现.本文分别以球面、环面、Möbius带及类丘陵曲面为代表仿真分析了黎曼曲面的紧致性、亏格、可定向性及高斯曲率等性质对模型的影响.结果显示,紧致性导致粒子群聚合得更加紧密对称,非零亏格导致群体中粒子的运动速度趋于一致并阻止粒子群形成类涡流形态,不可定向性导致粒子群在任何条件下都趋于分散,而高斯曲率对粒子群运动行为的影响较小.此外,本文还研究了当曲面包含一个、两个及三个障碍物时模型的输出,结果显示,当势强度足够大时,粒子群能够趋向目标,也能包围目标或绕行障碍物.综上,相比已有模型,该模型能够描述更为丰富的运动模式.

关键词：粒子群协同运动黎曼流形迴避

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Exceptionally Preserved Conodont Natural Assemblages from the Middle Triassic luoping Biota,Yunnan Province,China:Implications for Architecture of Conodont Feeding Apparatus

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Journal of Earth Science 2023年第6期34卷 1762-1776页

作者： Jinyuan Huang Carlos Martinez-Perez Qiyue Zhang Kexin Zhang mao luo Wen Wen Changyong Zhou Xiao Min Zhixin Ma Tao Xie Michael J.Benton Philip C.J.Donoghue Chengdu Center China Geological Survey(Geosciences Innovation Center of Southwest China)Chengdu 610081China Cavanilles Institute of Biodiversity&Evolutionary Biology University of Valencia46980 ValenciaSpain Institute of Geological Survey China University of GeosciencesWuhan 430074China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China School of Ocean Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences University of BristolBristol BS81TQUK

Articulated natural assemblages contain direct evidence of the element numbers,morphologies,positions and structures for reconstructing the feeding apparatuses of conodont animals,but these kind of materials are very rare in fossil records.Here we report ten new conodont natural assemblages from Member II of the Guanling Formation in luoping County,eastern Yunnan Province,southwestern China.These assemblages were obtained from the fossil-bearing layers of the luoping Biota,dated to the early Middle Triassic Anisian stage(Pelsonian substage).These fossiliferous laminated limestones mainly consist of calcites and dolomites,with platy clay minerals and pyrites as subordinate components,indicating that the conodont assemblages were preserved in a lower energy and anoxic sedimentary environment.The new natural assemblages preserve the primary collapse orientations of the Nicoraella feeding apparatus from the luoping Biota,showing the relative original positions of the S,M and P elements,that could be further used to refine the architecture of this apparatus in space variable M elements and the position unclear P1 elements.Integrating previously reported three-dimensional and bilaterally symmetrical fused clusters,we statistically analyze the size of the positional homogenous elements within different sized materials,in particular S4,S3,or S2 elements,indicates that elements ontogenic changes do not affect the apparatus architecture.Architecture of Nicoraella apparatus remains stable in the process of ontogeny,so our reconstructed model is credible.It is the first time that ample types of materials have been used to restore a conodont apparatus within one genus,namely natural assemblages(articulated and disarticulated),fused clusters(articulated,disarticulated,compressed,and relatively three-dimensional),and abundant discrete elements,respectively.These materials together record the most complete information on architecture in the gondolelloid apparatuses,thus enabling us to reconstruct a reliable fifteen-element appar

关键词： conodont natural assemblage architecture fused cluster size variation limestone MiddleTriassic southwestern China

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A branching heuristic for SAT solvers based on complete implication graphs

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Science China(Information Sciences) 2019年第7期62卷 170-182页

作者： Fan XIAO Chu-Min LI mao luo Felip MANYA Zhipeng Lü Yu LI School of Computer Science Huazhong University of Science and Technology Modélisation Information et Systèmes (MIS) University of Picardie Jules Verne

The performance of modern conflict-driven clause learning(CDCL) SAT solvers strongly depends on branching heuristics. State-of-the-art branching heuristics, such as variable state independent decaying sum(VSIDS) and learning rate branching(LRB), are computed and maintained by aggregating the occurrences of the variables in conflicts. However, these heuristics are not sufficiently accurate at the beginning of the search because they are based on very few conflicts. We propose the distance branching heuristic, which,given a conflict, constructs a complete implication graph and increments the score of a variable considering the longest distance between the variable and the conflict rather than the simple presence of the variable in the graph. We implemented the proposed distance branching heuristic in Maple LCM and Glucose-3.0, two of the best CDCL SAT solvers, and used the resulting solvers to solve instances from the application and crafted tracks of the 2014 and 2016 SAT competitions and the main track of the 2017 SAT competition. The empirical results demonstrate that using the proposed distance branching heuristic in the initialization phase of Maple LCM and Glucose-3.0 solvers improves performance. The Maple LCM solver with the proposed distance branching heuristic in the initialization phase won the main track of the 2017 SAT competition.

关键词： SAT branching heuristic conflict-driven clause learning implication graph

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Great Paleozoic-Mesozoic Biotic Turnings and Paleontological Education in China: A Tribute to the Achievements of Professor Zunyi Yang

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Journal of Earth Science 2018年第4期29卷 721-732页

作者： Zhong-Qiang Chen Laishi Zhao Xiangdong Wang mao luo Zhen Guo State Key Laboratory of Biogeology and Environmental Geology China University of SciencesWuhan State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan School of Life and Environmental Sciences (Melbourne Burwood Campus) Deakin University

Professor Zunyi Yang is a pioneer paleontologist who established the earliest Paleontological education and research in China, and has contributed his lifetime to promotion of Chinese paleontological education and researches as well as the studies on the Permian-Triassic （P-Tr） mass extinction and its possible causes. Yang has studied six fossil clades and trace fossils, together with his colleagues, he has established 6 new species of cephalopods, 1 new genus and 15 new species of gastropods, 8 new genera and 31 new species of bivalves, 17 new genera and 66 new species of brachiopods, 1 new genus and 4 new species of ophiuroids, 2 new genera and 7 new species of triopsids （Crustacea）, and 3 new ichnogenera and 7 new ichnospeeies of trace fossils. Yang led the 2nd IGCP working on the P-Tr mass extinction in the world. His group＇s excellent works on basic stratigraphy and paleontology enable the GSSP of P-~r boundary （PTB） to be ratified in China. Yang＇s earlier works on three-episode extinction pattern and volcanism-causing extinction hypothesis are also highlighted here to show how their first-hand data and initiative hypothesis have influenced the current and ongoing debates on the P-Tr crisis and possible causation. Yang school＇s extinction pattern is reviewed here, and their 2nd phase of extinction is marked by a dramatic loss in biodiversity, pointing to a widely accepted mass extinction. The 3rd extinction is characterized by ecological collapse of ecosystem structures and disappearance of the PTB microbialite ecosystem, while the 1st extinction （also prelude extinction） is indicated by the collapses of deep-water and reef ecosystems. Updated studies show that the volcanic ashes near the PTB originated from silicic, subduction-related igneous activity with little or no basaltic input. This subduction zone activity is related to closure of the Paleo-Tethys Ocean, and the intensity and frequency of the volcanic activity appear to increase near the P-Tr extinction interval. Hg anomalies （Hg/TOC ratios and Hg i

关键词： Professor Zunyi Yang IGCP project Permian-Triassic boundary mass extinction South China.

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Microbially Induced Carbonate Precipitation in a Middle Triassic Microbial Mat Deposit from Southwestern China:New Implications for the Formational Process of Micrite

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Journal of Earth Science 2021年第3期32卷 633-645页

作者： mao luo Jitao Chen Wenkun Qie Jinyuan Huang Qiyue Zhang Changyong Zhou Wen Wen State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PalaeoenvironmentChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Institute of Geological Survey China University of GeosciencesWuhan 430074China Chengdu Center of China Geological Survey Chengdu 610081China

Lime mud(i.e.,micrite)is a major component of carbonate deposits.Various mechanisms(biotic versus abiotic)have been proposed for the formation of lime mud in Earth’s history.However,the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be resolved.Herein we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province,southwestern China.Morphological features,together with previous geobiological investigations,suggest that the laminated lime mudstones represent the former presence of microbial mats.These lime mudstones consist mainly of calcite,dolomite and quartz,with clay minerals and pyrites as subordinate components.In particular,micro-analysis shows copious nano-globules(65–878 nm)and capsule-shaped nano-rods in laminations.These low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances(EPS).Nano-sized globules coalesce to form semi-euhedral micrite crystals.We suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local micro-environment.As an intermediate,these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process.

关键词： nano-globule EPS micrite microbial mat Middle Triassic luoping Biota

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基于生物信息学筛选食管鳞状细胞癌生物标志物

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西部医学 2024年第7期36卷 943-950页

作者：文婷罗茂康敏西南医科大学附属医院消化内科四川泸州646000 西南医科大学药物研究中心四川泸州646000

目的应用生物信息学筛选食管鳞状细胞癌(ESCC)组织中差异表达的microRNA(miRNA)并预测其靶基因,分析生物学功能。方法收集西南医科大学附属医院2021年6月—2022年2月期间的20对食管鳞状细胞癌癌组织和癌旁正常配对组织标本。通过GEO数... 详细信息

目的应用生物信息学筛选食管鳞状细胞癌(ESCC)组织中差异表达的microRNA(miRNA)并预测其靶基因,分析生物学功能。方法收集西南医科大学附属医院2021年6月—2022年2月期间的20对食管鳞状细胞癌癌组织和癌旁正常配对组织标本。通过GEO数据库下载ESCC miRNA表达谱芯片数据,利用R软件limma包进行归一化,筛选差异表达miRNA;利用在线工具Kaplan-meier Plotter对差异表达miRNA进行生存分析。通过qRT-PCR验证与生存率相关的差异miRNA在ESCC组织中的表达;利用TargetScan和miRDB预测靶基因,应用DAVID对靶基因进行GO功能注释和KEGG通路富集分析;通过STRING和Cytoscape构建PPI网络鉴定核心基因并构建miRNA-mRNA网络图;最后利用UALCAN评估核心基因在食管癌中的表达。结果与癌旁正常组织相比,hsa-miR-93、hsa-miR-130b、hsa-miR-18a、hsa-miR-23b在ESCC组织中表达上调;而hsa-miR-1、hsa-miR-133b、hsa-miR-378a在ESCC组织中表达下调。其中3种下调miRNA在ESCC组织中的表达较癌旁正常组织有显著差异(P<0.01)。核心基因HNRNPK、HNRNPU、DHX15、MATR3、HNRNPA3在食管癌中的表达明显上调,且与hsa-miR-1密切相关。结论ESCC癌组织中miRNA存在差异表达,miRNA可能通过作用靶基因间接参与调控相关的生物功能和通路,从而影响ESCC的发生发展。

关键词：食管鳞状细胞癌 microRNA 生物标志物基因生物信息学分析

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