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The Weng'an biota and the Ediacaran radiation of multicellular eukaryotes

National Science Review 2014年第4期1卷 498-520页

作者： Shuhai Xiao A.d.Muscente Lei Chen Chuanming Zhou james d.schiffbauer Andrew d.Wood Nicholas F.Polys Xunlai Yuan department of Geosciences Virginia Polytechnic Institute and State University State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute ofGeology and Paleontology Chinese Academy of Sciences department of Geological Sciences University of Missouri Advanced Research Computing Virginia Polytechnic Institute and State University

The rise of multicellularity represents a major evolutionary transition and it occurred independently in multiple eukaryote *** simple multicellular organisms may have evolved in the Mesoproterozoic Era or even earlier,complex multicellular eukaryotes began to diversify only in the Ediacaran Period,just before the Cambrian ***,the Ediacaran fossil record can provide key paleontological evidence about the early radiation of multicellular eukaryotes that ultimately culminated in the Cambrian *** Ediacaran Weng’an biota in South China hosts exceptionally preserved eukaryote fossils,including various acanthomorphic acritarchs,pseudoparenchymatous thalli,tubular microfossils,and spheroidal fossils such as Megasphaera,Helicoforamina,Spiralicellula,and *** of these fossils have been interpreted as multicellular eukaryotes,although alternative interpretations have also been *** this review,we critically examine these various interpretations,focusing particularly on Megasphaera,which has been variously interpreted as a sulfur-oxidizing bacterium,a unicellular protist,a mesomycetozoean-like holozoan,a volvocine green alga,a stem-group animal,or a crown-group *** conclude that Megasphaera is a multicellular eukaryote with evidence for cell-to-cell adhesion,a lexible membrane unconstrained by a rigid cell wall,spatial cellular diferentiation,germ–soma separation,and programmed cell *** features are inconsistent with the bacterium,unicellular protist,and mesomycetozoean-like holozoan ***,the surviving hypotheses,particularly the stem-group animal and algal interpretations,should be further tested with additional *** Weng’an biota also hosts cellularly diferentiated pseudoparenchymatous thalli with specialized reproductive structures indicative of an ainity with lorideophyte red *** other Weng’an fossils reviewed here may also be multicellular eukaryotes,although direct cellular evidenc

关键词： Ediacaran Period doushantuo Formation Weng’an biota multicellularity eukaryotes animals algae

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中元古代汝阳群化石细胞核状结构研究

中元古代汝阳群化石细胞核状结构研究

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全国微体古生物学分会第九届会员代表大会暨第十四次学术年会、全国化石藻类专业委员会第七届会员代表大会暨第十五次学术讨论会

作者：庞科唐卿肖书海 james d.schiffbauer 姚锦仙袁训来万斌陈雷欧志吉现代古生物学和地层学国家重点实验室中国科学院南京地质古生物研究所 department of Geosciences Virginia Polytechnic Institute and State University department of Geological Sciences University of Missouri 北京大学生命科学学院

真核生物的起源是生物进化历程上重大的里程碑之一,但早期真核生物的化石记录非常稀少且具有争议性。细胞大小曾经被当做判断是否为真核生命的一个有用的指标,但真核细胞和原核细胞大小之间也存在着相当大的重叠范围,使得细胞大小不能... 详细信息

真核生物的起源是生物进化历程上重大的里程碑之一,但早期真核生物的化石记录非常稀少且具有争议性。细胞大小曾经被当做判断是否为真核生命的一个有用的指标,但真核细胞和原核细胞大小之间也存在着相当大的重叠范围,使得细胞大小不能单独地作为真核生命的确切证据。最近细胞壁超微结构越来越多地被用来当做真核生命的证据。来自华北地台南缘汝阳群的碳质压膜疑源类化石Shuiyousphaeridium macroreticulatum、dictyosphaera delicata被广泛地认为是早期真核生物的代表。这两类分子是汝阳群中数量

关键词：核状结构细胞内含物中元古代汝阳群

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Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.james J.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

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Competitive interactions and coexistence of sympatric flagship carnivores in Asia

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Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin LI Jiayu LU Xiaoyi SHI Li’an dUO james L.d.SMITH Tianming WANG Tianjin Key Laboratory of Conservation and Utilization of Animal diversity College of Life SciencesTianjin Normal UniversityTianjinChina department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key Laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National Forestry and Grassland Administration Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard BeijingChina

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(***)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and *** and ungulate density were the most important predictors in regulating the coexistence *** and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial *** addition,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad ***-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition

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Time-Aware LSTM Neural Networks for dynamic Personalized Recommendation on Business Intelligence

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Tsinghua Science and Technology 2024年第1期29卷 185-196页

作者： Xuan Yang james A.Esquivel Graduate School Angeles University FoundationAngeles City 2009Philippines Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyWeifang 262700China

Personalized recommendation plays a critical role in providing decision-making support for product and service analysis in the field of business ***,deep neural network-based sequential recommendation models gained considerable ***,existing approaches pay litle attention to users'dynamically evolving interests,which are influenced by product attributes,especially product *** overcome these challenges,we propose a dynamic personalized recommendation model:***,we first embed product information and attribute information into a unified data ***,we exploit long short-term memory(LsTM)networks to characterize sequential behavior over multiple time periods and seize evolving interests by hierarchical LSTM ***,similarity values between users are measured through pairwise interest features,and personalized recommendation lists are generated.A series of experiments reveal the superiority of the proposed method compared withotheradvanced methods.

关键词： personalized recommendations evolving interests embedding LsTM networks

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Probing turbulence in galaxies with fast radio burst scintillation

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： james M.Cordes department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-known phenomenon observed from pulsars in the Milky *** comprises intensity variations *** and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISM)on scales as small as~100 *** density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

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LSTM Network-Based Adaptation Approach for dynamic Integration in Intelligent End-Edge-Cloud Systems

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Tsinghua Science and Technology 2024年第4期29卷 1219-1231页

作者： Xuan Yang james A.Esquivel Graduate School Angeles University FoundationAngeles City 2009Philippinesand also with Shandong Provincial University Laboratory for Protected HorticultureWeifang University of Science and TechnologyWeifang 262700China Graduate School Angeles University FoundationAngeles City 2009Philippines

Edge computing, which migrates compute-intensive tasks to run on the storage resources of edge devices, efficiently reduces data transmission loss and protects data privacy. However, due to limited computing resources and storage capacity, edge devices fail to support real-time streaming data query and processing. To address this challenge, first, we propose a Long Short-Term Memory (LSTM) network-based adaptive approach in the intelligent end-edge-cloud system. Specifically, we maximize the Quality of Experience (QoE) of users by automatically adapting their resource requirements to the storage capacity of edge devices through an event mechanism. Second, to reduce the uncertainty and non-complete adaption of the edge device towards the user’s requirements, we use the LSTM network to analyze the storage capacity of the edge device in real time. Finally, the storage features of the edge devices are aggregated to the cloud to re-evaluate the comprehensive capability of the edge devices and ensure the fast response of the user devices during the dynamic adaptation matching process. A series of experimental results show that the proposed approach has superior performance compared with traditional centralized and matrix decomposition based approaches.

关键词： quality of experience data query end-edge-cloud Long Short-Term Memory(LSTM)networks

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Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： K james Jintu KIM Heuy dong department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAd-IT Korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

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Functionalization of cellulose carbon dots with different elements(N,B and S)for mercury ion detection and anti-counterfeit applications

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Chinese Chemical Letters 2024年第7期35卷 355-359页

作者： Xiaoning Li Quanyu Shi Meng Li Ningxin Song Yumeng Xiao Huining Xiao Tony d.james Lei Feng Second Affiliated Hospital of dalian Medical University Dalian 116023China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science and EngineeringNorth China Electric Power UniversityBaoding 071003China department of Chemical Engineering and Limerick Pulp&Paper Centre University of New Brunswick15 Dineen DriveFredericton NB E3B 5A3Canada department of Chemistry University of BathBath BA27AYUnited Kingdom School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Mercury ion(Hg^(2+)),as one of the most toxic heavy metal ions,accumulates easily in the environment,which can generate potential hazards to the ecosystem and human *** effectively detect and remove Hg^(2+),we fabricated four types of carbon dots(Cds)using carboxymethyl nanocellulose as a carbon source doped with different elements using a hydrothermal *** the Cds exhibited a strong fluorescence emission,excitation-dependent emission and possessed good water ***,the four fluorescent Cds were used for Hg^(2+)recognition in aqueous solution,where the Cds-N exhibited better sensitivity and selectivity for Hg^(2+)detection,with a low limit of detection of 8.29×10^(-6)mol/*** was determined that the fluorescence quenching could be ascribed to a photoinduced charge-transfer processes between Hg^(2+)and the *** addition,the Cds-N were used as a smart invisible ink for anticounterfeiting,information encryption and ***,the Cds-N were immersed into a cellulose(CMC)-based hydrogel network to prepare fluorescent hydrogels capable of simultaneously detecting and adsorbing Hg^(2+).We anticipate that this research will open possibilities for a green method to synthesize fluorescent Cds for metal ion detection and fluorescent ink production.

关键词： Carbon dots Functional groups Hg^(2+)detection Mechanism Anti-counterfeiting

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Event-triggered sliding mode control of linear repetitive processes and its application in metal rolling process

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Science China(Information Sciences) 2024年第3期67卷 167-181页

作者： Xinyu LV Yugang NIU james LAM Key Laboratory of Smart Manufacturing in Energy Chemical Process (East China University of Science and Technology) Ministry of Education department of Mechanical Engineering The University of Hong Kong

This paper investigates the design problem of a sliding mode controller for linear repetitive processes(LRPs) with a finite pass length on each pass. Under limited communication resources, an eventtriggered mechanism is implemented from the sensors to the controller, whose triggered sequence is consistent with the evolution direction of LRPs. To periodically orchestrate communication between the controller and actuator, a round-robin scheduling mechanism is established based on the pass length. A sliding function involving the state and pass profile is constructed, and the sliding mode controller is designed using triggered states and pass profile signals. Feasible controller gains are attained to ensure the stability of the resultant closed-loop system. Finally, the proposed strategy is implemented for a multi-roll metal rolling process.

关键词： event-triggered mechanism linear repetitive processes metal rolling process round-robin scheduling sliding mode control

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