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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-Heng Du Yong-min shi State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences School of Earth and Space Sciences Peking University

In this study, a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed. “Pore-throat solidity”, which is analogous to particle solidity, and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are introduced. Additionally, the “pore-throat combination” and “pure pore” are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff point. When the discrete grid set is recognized as a pore-throat combination, Legendre ellipse fitting and minimum Feret diameter are used. When the pore and throat grid sets are identified as pure pores, the pore diameter can be directly calculated. Using the new method, the analytical results for the physical parameters and pore radius agree well with most prior studies. The results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano scales. The new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

Generating diverse clothed 3D human animations via a generative model

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Computational Visual Media 2024年第2期10卷 261-277页

作者： min shi Wenke Feng Lin Gao Dengming Zhu School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

Data-driven garment animation is a current topic of interest in the computer graphics industry.Existing approaches generally establish the mapping between a single human pose or a temporal pose sequence,and garment deformation,but it is difficult to quickly generate diverse clothed human animations.We address this problem with a method to automatically synthesize dressed human animations with temporal consistency from a specified human motion label.At the heart of our method is a twostage strategy.Specifically,we first learn a latent space encoding the sequence-level distribution of human motions utilizing a transformer-based conditional variational autoencoder(Transformer-CVAE).Then a garment simulator synthesizes dynamic garment shapes using a transformer encoder-decoder architecture.Since the learned latent space comes from varied human motions,our method can generate a variety of styles of motions given a specific motion label.By means of a novel beginning of sequence(BOS)learning strategy and a self-supervised refinement procedure,our garment simulator is capable of efficiently synthesizing garment deformation sequences corresponding to the generated human motions while maintaining temporal and spatial consistency.We verify our ideas experimentally.This is the first generative model that directly dresses human animation.

关键词： Transformer garment animation conditional variational autoencoder(CVAE) computer graphics

Moderate Deviations for Parameter Estimation in the Fractional Ornstein–Uhlenbeck Processes with Periodic Mean

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1308-1324页

作者： Hui JIANG shi min LI Wei Gang WANG School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China The People's Bank of China Operations Ofice of Nanjing Branch Nanjing 210016P.R.China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018P.R.China

In this paper,we study the asymptotic properties for the drift parameter estimators in the fractional Ornstein-Uhlenbeck process with periodic mean function and long range dependence.The Cremér-type moderate deviatio... 详细信息

关键词： Cramér-type moderate deviation fractional Ornstein-Uhlenbeck process parameter estimation multiple Wiener-Ito integrals

Molecular regulation of the key specialized metabolism pathways in medicinal plants

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Journal of Integrative Plant Biology 2024年第3期66卷 510-531页

作者： min shi Siwei Zhang Zizhen Zheng Itay Maoz Lei Zhang Guoyin Kai Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and TransformationSchool of Pharmaceutical SciencesJinhua AcademyZhejiang Chinese Medical UniversityHangzhou 310053China Department of Postharvest Science Agricultural Research OrganizationVolcani CenterRishonLeZion 7505101Israel Department of Pharmaceutical Botany School of PharmacyNaval Medical UniversityShanghai 200433China

The basis of modern pharmacology is the human ability to exploit the production of specialized metabolites from medical plants,for example,terpenoids,alkaloids,and phenolic acids.However,in most cases,the availability of these valuable compounds is limited by cellular or organelle barriers or spatio-temporal accumulation patterns within different plant tissues.Transcription factors(TFs)regulate biosynthesis of these specialized metabolites by tightly controlling the expression of biosynthetic genes.Cutting-edge technologies and/or combining multiple strategies and approaches have been applied to elucidate the role of TFs.In this review,we focus on recent progress in the transcription regulation mechanism of representative high-value products and describe the transcriptional regulatory network,and future perspectives are discussed,which will help develop high-yield plant resources.

关键词： biosynthesis medicinal plants omics secondary metabolism transcription factors

Dissolved organic matter accelerates microbial degradation of 17 alpha-ethinylestradiol in the presence of iron mineral

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Journal of Environmental Sciences 2024年第5期139卷 364-376页

作者： Huan He min shi Xiaoxia Yang Juhong Zhan Yanting Lin Ziwei Guo Zhicheng Liao Chaochao Lai Xiaomin Ren Bin Huang Xuejun Pan Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control Kunming 650500China Research Institute for Environmental Innovation(Suzhou)Tsinghua Suzhou 215163China

Dissolved organic matter(DOM)and iron minerals widely existing in the natural aquatic environment can mediate the migration and transformation of organic pollutants.However,the mechanism of interaction between DOM and iron minerals in the microbial degradation of pollutants deserves further investigation.In this study,the mechanism of 17 alphaethinylestradiol(EE2)biodegradation mediated by humic acid(HA)and three kinds of iron minerals(goethite,magnetite,and pyrite)was investigated.The results found that HA and iron minerals significantly accelerated the biodegradation process of EE2,and the highest degradation efficiency of EE2(48%)was observed in the HA-mediated microbial system with pyrite under aerobic conditions.Furthermore,it had been demonstrated that hydroxyl radicals(HO·)was the main active substance responsible for the microbial degradation of EE2.HO·is primarily generated through the reaction between hydrogen peroxide secreted by microorganisms and Fe(II),with aerobic conditions being more conducive.The presence of iron minerals and HA could change the microbial communities in the EE2 biodegradation system.These findings provide new information for exploring the migration and transformation of pollutants by microorganisms in iron-rich environments.

关键词： Dissolved organic matter Iron mineral 17 alpha-ethinylestradiol Biodegradation

Development and validation of a nomogram for predicting in-hospital mortality of intensive care unit patients with liver cirrhosis

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World Journal of Hepatology 2024年第4期16卷 625-639页

作者： Xiao-Wei Tang Wen-Sen Ren Shu Huang Kang Zou Huan Xu Xiao-min shi Wei Zhang Lei shi Mu-Han Lü Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Nuclear Medicine and Molecular Imaging Key Laboratory The Affiliated Hospital of Southwest Medical UniversityLuzhou 646099Sichuan ProvinceChina Department of Gastroenterology Lianshui People’Hospital of Kangda College Affiliated to Nanjing Medical UniversityHuaian 223499Jiangsu ProvinceChina

BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality rate.AIM To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver cirrhosis.METHODS We extracted demographic,etiological,vital sign,laboratory test,comorbidity,complication,treatment,and severity score data of liver cirrhosis patients from the Medical Information Mart for Intensive Care IV(MIMIC-IV)and electronic ICU(eICU)collaborative research database(eICU-CRD).Predictor selection and model building were based on the MIMIC-IV dataset.The variables selected through least absolute shrinkage and selection operator analysis were further screened through multivariate regression analysis to obtain final predictors.The final predictors were included in the multivariate logistic regression model,which was used to construct a nomogram.Finally,we conducted external validation using the eICU-CRD.The area under the receiver operating characteristic curve(AUC),decision curve,and calibration curve were used to assess the efficacy of the models.RESULTS Risk factors,including the mean respiratory rate,mean systolic blood pressure,mean heart rate,white blood cells,international normalized ratio,total bilirubin,age,invasive ventilation,vasopressor use,maximum stage of acute kidney injury,and sequential organ failure assessment score,were included in the multivariate logistic regression.The model achieved AUCs of 0.864 and 0.808 in the MIMIC-IV and eICU-CRD databases,respectively.The calibration curve also confirmed the predictive ability of the model,while the decision curve confirmed its clinical value.CONCLUSION The nomogram has high accuracy in predicting in-hospital mortality.Improving the included predictors may help improve the prognosis of patients.

关键词： Liver cirrhosis Intensive care unit Nomogram Predicting model Mortality

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-Bin Liu Shen Huang Ding-Chao Tian Lai-min shi Shan-Bi Peng He Zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD

Amino acids TORC(talk) to anabolism through uncharged tRNA

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Science China Life Sciences 2024年第8期 1775-1776页

作者： Zhen-Zhen Ma shi-min Zhao The Obstetrics & Gynecology Hospital of Fudan University State Key Laboratory of Genetic EngineeringShanghai Key Laboratory of Metabolic Remodelling and HealthFudan University

Anabolism is essential for proliferation as well as to replenish dysfunctional macromolecules in cells.Due to that both substantial building blocks and energy are required for anabolism,cells must double check whether these prerequisites are met before deciding to start anabolism.Amino acids are building blocks of protein synthesis,their sufficiency in cells is closely monitored by several mechanisms,which all are linked to protein synthesis.

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枢纽型社会组织高质量参与基层治理的影响因素与实现路径

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社会政策研究 2024年第2期35卷 107-118,135,136页

作者：张冉石敏华东师范大学公共管理学院华东师范大学社会组织与社会治理创新研究中心

在街镇社区层面,枢纽型社会组织在党和政府与一般性社会组织间扮演着枢纽桥梁角色,为增强基层治理效能提供了动力来源与创新载体。借助于上海市25个街镇级社会组织服务中心样本,本文采用模糊集定性比较分析方法,分析了经济发展水平、政... 详细信息

在街镇社区层面,枢纽型社会组织在党和政府与一般性社会组织间扮演着枢纽桥梁角色,为增强基层治理效能提供了动力来源与创新载体。借助于上海市25个街镇级社会组织服务中心样本,本文采用模糊集定性比较分析方法,分析了经济发展水平、政府支持力度、社会组织互动、社会关系链接、组织硬件基础和组织软件条件等组合下枢纽型社会组织高质量参与基层治理的影响因素和实现路径。研究结果显示:(1)组织硬件基础是枢纽型社会组织高质量参与基层治理的必要条件;(2)枢纽型社会组织高质量参与基层治理具有资源赋能型、社会撬动型、复合推进型、内外协同型四种“殊途同归”的实现路径。本研究丰富了社会组织理论研究,研究结论可为地方因地制宜地推进枢纽型社会组织高质量参与基层治理提供有益的借鉴。

关键词：枢纽型社会组织社会组织服务中心基层治理组态分析

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知识分类视角下晚清西学汇编中物理知识的表达与认知

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自然辩证法研究 2024年第2期40卷 110-116页

作者：杨诗敏聂馥玲郭世荣内蒙古师范大学科学技术史研究院呼和浩特010022

如何理解两种文化相遇时“本土”与“域外”之间的知识融通是探讨近代中国西学东渐的重要议题。透过晚清西学汇编对物理知识的本土回应或可发现问题的关键。这些汇编资料再次选择与重述已有西学译书,对传入知识进行二度创造。其中的知... 详细信息

如何理解两种文化相遇时“本土”与“域外”之间的知识融通是探讨近代中国西学东渐的重要议题。透过晚清西学汇编对物理知识的本土回应或可发现问题的关键。这些汇编资料再次选择与重述已有西学译书,对传入知识进行二度创造。其中的知识分类呈现出新知与旧识之间的往还,反映出时人对物理知识的认知。西学汇编对传入物理知识再生产的复杂历史情节,显示晚清中国学者对物理学的认识不止由器物上升到学理,还有着以“艺”描述其知识属性,以“测量”“格物”概括其知识领域的尝试。解析西学汇编对物理知识的调适与回应,也是审视晚清物理学本土化的主旨所在。

关键词：晚清西学汇编知识分类百科全书物理学