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Carbon Sequestration in Two Alpine Soils on the Tibetan Plateau

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Journal of Integrative Plant Biology 2009年第9期51卷 900-905页

作者： Yu-Qiang Tian xing-liang xu Ming-Hua Song Cai-Ping Zhou Qiong Gao Hua Ouyang College of Resources Science & Technology State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 China

Soil carbon sequestration was estimated in a conifer forest and an alpine meadow on the Tibetan Plateau using a carbon- 14 radioactive label provided by thermonuclear weapon tests （known as bomb-^14C）. Soil organic matter was physically separated into light and heavy fractions. The concentration spike of bomb-^14C occurred at a soil depth of 4 cm in both the forest soil and the alpine meadow soil. Based on the depth of the bomb-^14C spike, the carbon sequestration rate was determined to be 38.5 g C/m^2 per year for the forest soil and 27.1 g C/m^2 per year for the alpine meadow soil. Considering that more than 60% of soil organic carbon （SOC） is stored in the heavy fraction and the large area of alpine forests and meadows on the Tibetan Plateau, these alpine ecosystems might partially contribute to ＂the missing carbon sink＂.

关键词： alpine soils bomb carbon carbon sequestration soil organic carbon.

Collective Movement Simulation:Methods and Applications

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Machine Intelligence Research 2024年第3期21卷 452-480页

作者： Hua Wang xing-Yu Guo Hao Tao Ming-liang xu School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou450001China Engineering Research Center of Intelligent Swarm Systems Ministry of EducationZhengzhou450001China National Supercomputing Center in Zhengzhou Zhengzhou450001China China Ship Development and Design Center Wuhan430060China

Collective movement simulations are challenging and important in many areas,including life science,mathematics,physics,information science and public *** this survey,we provide a comprehensive review of the state-of-the-art techniques for collective movement *** start with a discussion on certain concepts to help beginners understand it more ***,we analyze the intelligence among different collective objects and the emphasis in different ***,we classify existing collective movement simulation methods into four categories according to their effects,namely versatility,accuracy,dynamic adaptability,and assessment feedback ***,we introduce five applications of layout optimization,emergency control,dispatching,unmanned systems,and other derivative ***,we summarize possible future research directions.

关键词： Collective movement simulation multiple objects multiple discipline simulation effect collective intelligence

Enhanced Flexoelectricity in Barium Titanate-Cellulose Composite Thin Films

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Acta Mechanica Solida Sinica 2024年第4期37卷 521-527页

作者： Wensi xing Hongyu Cao Xin Zhang xu liang Jianwei Song Shengping Shen Chemomechanics and Intelligent Media Laboratory State Key Laboratory for Strength and Vibration of Mechanical StructuresSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China

Biopolymers,the potential flexoelectric materials,are environment-friendly,degradable,lightweight,cost-effective,and possess remarkable processing properties catering to the requirements of advanced ***,the flexoelectric coefficient of biopolymers is normally much weaker than that of ceramic materials,limiting their potential applications for designing high-performance green electromechanical coupling *** improve the flexoelectric response in biopolymers,we composited barium titanate(BTO)with 2,2,6,6-tetramethylpiperidine-1-oxyl-oxidized cellulose nanofibrils(TOCNF)to enhance the flexoelectric response of *** to the high permittivity and flexoelectric effect of BTO,the relative dielectric constant and flexoelectric coefficient of 33.3 wt%BTO-TOCNF films reached 30.94@1 kHz and 50.05±1.88 nC/m@1 Hz,which were almost 172 times and 27 times higher than those of TOCNF,*** composite thin film contains high dielectric constant and flexoelectric coefficient,as well as excellent *** study provided a straightforward and efficient method for improving the flexoelectric effect of biopolymers,and demonstrated its great potential applications in flexoelectric-based devices.

关键词： Flexoelectricity Cellulose BaTiO_(3) Composite Thin films

Small-scale switch in cover-perimeter relationships of patches indicates shift of dominant species during grassland degradation

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Journal of Plant Ecology 2020年第6期13卷 704-712页

作者： Ming-Hua Song Johannes HCCornelissen Yi-Kang Li xing-liang xu Hua-Kun Zhou Xiao-Yong Cui Yan-Fen Wang Rong-Yan xu Qi Feng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Systems Ecology Department of Ecological ScienceFaculty of Earth and Life SciencesVU UniversityDe Boelelaan 10851081 HV AmsterdamThe Netherlands College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and ResearchPlant Science Research CenterShanghai Chenshan Botanic GardenShanghai 201602China Key Laboratory of Ecohydrology of Inland River Basin Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Aims Grasslands are globally threatened by climate changes and unsustainable land-use,which often cause transitions among alternative stable states,and even catastrophic transition to *** vegetation patch configurations have been shown to signify such transitions at large spatial ***,we demonstrate how small-scale patch configurations can also indicate state *** The whole spatial series of degradation successions were chosen in alpine grasslands characterized as seven typical *** numbers,and perimeter and cover of each patch were recorded using adjacent quadrats along transects in each type of the *** abundance within each patch was *** Findings Across seven grazing-induced degradation stages in the world’s largest expanse of grassland,from dense ungrazed turf to bare black-soil crust,patch numbers and perimeters first increased as patch cover *** and perimeters then decreased rapidly beyond an intersection point at 68%of initial continuous vegetation *** this point,the vegetation fluctuated back and forth between the sedge-dominated grassland breaking-up phase and the forb-dominated phase,suggesting impending shift of grassland *** study thus demonstrates how ground-based small-scale vegetation surveys can provide a quantitative,easy-to-use signals for vegetation degradation,with promise for detecting the catastrophic transition to desertification.

关键词： grassland degradation state transition Tibetan Plateau trade-off vegetation patchiness

Surface diffraction beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 47-57页

作者： Yue-liang Gu xu Zheng xing-Min Zhang Bin Zhao Guang-Zhi Yin Da-Ming Zhu Yuan-He Sun xing-Yu Gao Xiao-Long Li Shanghai Advanced Research Institute Chinese Academy of Sciences239 Zhangheng RoadPudong DistrictShanghai201204China

BL02U2 of the Shanghai Synchrotron Radiation Facility is a surface diffraction beamline with a photon flux of 5.5×10^(12) photons/s at 10 keV and a beam size of 160µm×80µm at the sample *** is dedicated to studying surfaces(solid-vacuum,solid-gas)and interfaces(solid-solid,solid-liquid,and liquid-liquid)in nanoscience,condensed matter,and soft matter systems using various surface scattering techniques over an energy range of 4.8-28 keV with transmission and reflection ***,BL02U2 has a high energy resolution,high angular resolution,and low beam divergence,which can provide excellent properties for X-ray diffraction experiments,such as grazing incident X-ray diffraction,X-ray reflectivity,crystal truncation rods,and liquid X-ray *** of in situ environments can also be provided for the samples *** paper describes the setup of the new beamline and its applications in various fields.

关键词： Surface and interface Beamline Surface diffraction Microstructure

Dynamic interwell connectivity analysis of multi-layer waterflooding reservoirs based on an improved graph neural network

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Petroleum Science 2024年第2期21卷 1062-1080页

作者： Zhao-Qin Huang Zhao-xu Wang Hui-Fang Hu Shi-Ming Zhang Yong-xing liang Qi Guo Jun Yao School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Exploration and Development Research Institute Shengli OilfieldSINOPECDongying257015ShandongChina

The analysis of interwell connectivity plays an important role in the formulation of oilfield development plans and the description of residual oil distribution. In fact, sandstone reservoirs in China's onshore oilfields generally have the characteristics of thin and many layers, so multi-layer joint production is usually adopted. It remains a challenge to ensure the accuracy of splitting and dynamic connectivity in each layer of the injection-production wells with limited field data. The three-dimensional well pattern of multi-layer reservoir and the relationship between injection-production wells can be equivalent to a directional heterogeneous graph. In this paper, an improved graph neural network is proposed to construct an interacting process mimics the real interwell flow regularity. In detail, this method is used to split injection and production rates by combining permeability, porosity and effective thickness, and to invert the dynamic connectivity in each layer of the injection-production wells by attention *** on the material balance and physical information, the overall connectivity from the injection wells,through the water injection layers to the production layers and the output of final production wells is established. Meanwhile, the change of well pattern caused by perforation, plugging and switching of wells at different times is achieved by updated graph structure in spatial and temporal ways. The effectiveness of the method is verified by a combination of reservoir numerical simulation examples and field example. The method corresponds to the actual situation of the reservoir, has wide adaptability and low cost, has good practical value, and provides a reference for adjusting the injection-production relationship of the reservoir and the development of the remaining oil.

关键词： Graph neural network Dynamic interwell connectivity Production-injection splitting Attention mechanism Multi-layer reservoir

DMF-scMT-seq linking methylome and transcriptome within single cells with digital microfluidics

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Science China Chemistry 2024年第6期67卷 2070-2078页

作者： xing xu Xi Zeng Xin Lin Shiyan Lin Shanshan liang Tian Tian Rui Su Jia Song Chaoyong Yang Collaborative Innovation Center of Chemistry for Energy Materials The MOE Key Laboratory of Spectrochemical Analysis and InstrumentationState Key Laboratory of Physical Chemistry of Solid SurfacesDepartment of Chemical BiologyCollege of Chemistry and Chemical EngineeringThe First Affiliated Hospital of Xiamen UniversityXiamen UniversityXiamen361005China Institute of Molecular Medicine Renji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China Chemistry and Materials Science College Shanghai Normal UniversityShanghai200234China Chemistry and Biomedicine Innovation Center(ChemBIC) School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Single-cell joint analysis of methylome and transcriptome reveals how the methylation regulates the transcriptional ***,traditional bench-top protocols for single-cell DNA methylation and RNA transcription co-detection are laborintensive,cost-ineffective and ***,we establish the DMF-sc MT-seq,a highly-efficient and cost-effective method to simultaneously analyze single-cell DNA methylation and transcriptional activity based on digital *** MT-seq automates the workflow of single-cell isolation,cellular hypotonic lysis,nucleic acid separation and methylome/transcriptome library construction in a contactless and addressable *** system ensures high accuracy(R>0.85),high gene detection ability(14,697 genes per cell at 4 million sequencing depth),and high CpG coverage(677,198 CpG sites per cell at 1million sequencing depth).By using DMF-sc MT-seq,the relationship of DNA methylation and RNA transcription under different genomic contexts is *** further apply DMF-sc MT-seq to study the dynamics of transcription regulation with methylation-inhibiting anti-tumor Decitabine,and identify the methylated promoter/gene body driven genes in response to Decitabine ***-sc MT-seq facilitates the construction of the correlation of DNA methylation and transcriptional activity at the single-cell level in a flexible,sensitive and accurate way,which is anticipated to be a powerful tool in studying single-cell biological systems.

关键词： single-cell analysis digital microfluidics methylome sequencing transcriptome sequencing

Intensive management enhances mycorrhizal respiration but decreases free-living microbial respiration by affecting microbial abundance and community structure in Moso bamboo forest soils

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Pedosphere 2024年第2期34卷 508-519页

作者： Wenhao JIN Jiangfei GE Shuai SHAO Liyuan PENG Jiajia xing Chenfei liang Junhui CHEN Qiufang xu Hua QIN State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China School of Environmental and Resource Sciences Zhejiang A&F UniversityHangzhou 311300China

Intensive management is known to markedly alter soil carbon(C)storage and turnover in Moso bamboo forests compared with extensive ***,the effects of intensive management on soil respiration(RS)components remain *** study aimed to evaluate the changes in different RScomponents(root,mycorrhizal,and free-living microorganism respiration)in Moso bamboo forests under extensive and intensive management practices.A1-year in-situ microcosm experiment was conducted to quantify the RScomponents in Moso bamboo forests under the two management practices using mesh screens of varying *** results showed that the total RSand its components exhibited similar seasonal variability between the two management *** with extensive management,intensive management significantly increased cumulative respiration from mycorrhizal fungi by 36.73%,while decreased cumulative respiration from free-living soil microorganisms by 8.97%.Moreover,the abundance of arbuscular mycorrhizal fungi(AMF)increased by 43.38%,but bacterial and fungal abundances decreased by 21.65%and 33.30%,respectively,under intensive *** management practices significantly changed the bacterial community composition,which could be mainly explained by soil pH and available *** fungi and intensive management affected the interrelationships between bacterial *** equation modeling indicated that intensive management changed the cumulative RSby elevating AMF abundance and lowering bacterial *** concluded that intensive management reduced the microbial respiration-derived C loss,but increased mycorrhizal respiration-derived C loss.

关键词： arbuscular mycorrhizal fungi extensive management microbial co-occurrence network root respiration soil organic C soil respiration structural equation model

HgaNets:Fusion of Visual Data and Skeletal Heatmap for Human Gesture Action Recognition

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Computers, Materials & Continua 2024年第4期79卷 1089-1103页

作者： Wuyan liang Xiaolong xu School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210023China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210023China

Recognition of human gesture actions is a challenging issue due to the complex patterns in both visual andskeletal features. Existing gesture action recognition (GAR) methods typically analyze visual and skeletal data,failing to meet the demands of various scenarios. Furthermore, multi-modal approaches lack the versatility toefficiently process both uniformand disparate input ***, in this paper, an attention-enhanced pseudo-3Dresidual model is proposed to address the GAR problem, called HgaNets. This model comprises two independentcomponents designed formodeling visual RGB (red, green and blue) images and 3Dskeletal heatmaps, *** specifically, each component consists of two main parts: 1) a multi-dimensional attention module forcapturing important spatial, temporal and feature information in human gestures;2) a spatiotemporal convolutionmodule that utilizes pseudo-3D residual convolution to characterize spatiotemporal features of gestures. Then,the output weights of the two components are fused to generate the recognition results. Finally, we conductedexperiments on four datasets to assess the efficiency of the proposed model. The results show that the accuracy onfour datasets reaches 85.40%, 91.91%, 94.70%, and 95.30%, respectively, as well as the inference time is 0.54 s andthe parameters is 2.74M. These findings highlight that the proposed model outperforms other existing approachesin terms of recognition accuracy.

关键词： Gesture action recognition multi-dimensional attention pseudo-3D skeletal heatmap