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基于无监督学习方法的细胞膜内单分子扩散运动分析:胆固醇对模型膜和活细胞膜流动性的不同影响

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物理学报 2024年第18期73卷 278-288页

作者：谭金鹏张婉婷徐成卢雪梅朱文圣杨恺元冰东北师范大学数学与统计学院长春130024 松山湖材料实验室东莞523808 苏州大学物理科学与技术学院软凝聚态物理及交叉研究中心苏州215006 苏州城市学院光学与电子信息学院苏州215104 苏州大学前沿材料物理与器件省高校重点实验室苏州215006

单分子运动追踪是研究软物质体系尤其是生命体系动力学过程和分子相互作用的重要方法,但如何理解生命体系中单分子运动行为的复杂性仍是一个巨大的挑战.针对这一问题,本工作提出了一种可对单分子轨迹进行高效识别和分类的、基于无监督... 详细信息

单分子运动追踪是研究软物质体系尤其是生命体系动力学过程和分子相互作用的重要方法,但如何理解生命体系中单分子运动行为的复杂性仍是一个巨大的挑战.针对这一问题,本工作提出了一种可对单分子轨迹进行高效识别和分类的、基于无监督学习的“两步归类法”:首先利用熵约束最小二乘法对扩散轨迹的受限程度进行区分,继而通过统计检验将非受限轨迹划分为亚扩散、正常扩散和超扩散等不同运动模式类型.利用该方法,本工作解析了DOPC模型细胞膜和活细胞膜内的单分子扩散运动特征,揭示了胆固醇成分对二者的差异影响.结果显示:模型膜和活细胞膜均包含多种不同的扩散模式;在DOPC模型膜体系中,胆固醇成分会阻碍膜内的分子扩散运动,且阻碍程度与胆固醇含量正相关;在活细胞体系中,分子运动速率显著低于模型膜体系,并且,胆固醇的去除会进一步减慢分子扩散速率.本研究有助于从单分子运动角度深入理解生物分子运动行为的复杂性及其对体系环境的依赖性.

关键词：单分子运动无监督学习模型细胞膜胆固醇

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金属机械部件的疲劳损伤机制与寿命预测模型

模具技术 2024年第3期 1-7页

作者：程丽琴万茸程艳刘楠西安高新科技职业学院陕西西安713700 西安理工大学高科学院陕西西安713700

基于裂纹萌生与扩展的机制及金属部件疲劳损伤的各种主要因素,结合模具行业的特点和需求,开发了一种基于深度学习的寿命预测模型。仿真结果表明,该模型在预测模具金属部件的寿命方面具有较高的精度和可靠性。这对于模具制造和运行企业而... 详细信息

基于裂纹萌生与扩展的机制及金属部件疲劳损伤的各种主要因素,结合模具行业的特点和需求,开发了一种基于深度学习的寿命预测模型。仿真结果表明,该模型在预测模具金属部件的寿命方面具有较高的精度和可靠性。这对于模具制造和运行企业而言,不仅有助于他们更深入地理解金属部件的疲劳损伤行为,更能帮助他们准确预测部件的寿命,从而进行更为合理的工程设计和优化。

关键词：金属机械部件疲劳损伤机制寿命预测模型深度学习

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型壳加热温度对单晶高温合金显微组织及“雀斑”形成的影响

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Transactions of Nonferrous Metals Society of China 2024年第4期34卷 1191-1203页

作者：王志成李嘉荣刘世忠杨万鹏王效光北京航空材料研究院先进高温结构材料重点实验室北京100095

利用所设计的阶梯试样进行定向凝固试验和模拟,研究定向凝固过程型壳加热温度对单晶高温合金铸件显微组织和“雀斑”形成的影响。分析糊状区的温度场及形貌。结果表明,升高型壳加热温度,一次和二次枝晶间距减小,糊状区液相的渗透率和对... 详细信息

利用所设计的阶梯试样进行定向凝固试验和模拟,研究定向凝固过程型壳加热温度对单晶高温合金铸件显微组织和“雀斑”形成的影响。分析糊状区的温度场及形貌。结果表明,升高型壳加热温度,一次和二次枝晶间距减小,糊状区液相的渗透率和对流通道的宽度降低,“雀斑”形成倾向性降低,“雀斑”宽度减小,“雀斑”区域枝晶碎片减少。此外,随着型壳加热温度的升高,糊状区液相冷却速率增加,糊状区熔体的冷却时间减少,液体流动对枝晶的破碎程度得到削弱,这进一步降低单晶高温合金铸件“雀斑”形成的倾向性。

关键词：单晶高温合金 “雀斑”形成型壳加热温度定向凝固数值模拟

Vortical structures and wakes of a sphere in homogeneous and density stratified fluid

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Journal of Hydrodynamics 2021年第2期33卷 207-215页

作者： Liu-shuai Cao Feng-lai Huang cheng Liu De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil Engi-neeringShanghai Jiao Tong UniversityShanghai 200240China Ocean College Zhejiang UniversityZhoushan 316021China

Vortical structures and wakes of bluff bodies in homogenous and stratified environment are common and important in ocean *** on the Boussinesq approximation,a thermocline model is proposed to deal with the variable density stratified fluid,and implemented in the commercial software Simcenter STAR-CCM+*** improved delayed detached eddy simulation(IDDES)modeling method is adopted to resolve the coherent vortical structures and turbulent wakes precisely and *** conditions consisting of one homogenous and three stratified fluid cases with different density gradient past a sphere at Reynolds number 3700 are *** show that density stratification has a great impact on the vortical structures,the vertical motion is suppressed and internal waves will be induced and propagated,which is very different with that of homogenous *** the stratification strength increases,the vortical structures are gradually flattened,the asymmetry and anisotropy between vertical and horizontal motions are enhanced.

关键词： Vortical structures wakes sphere homogenous stratified fluid

A nonlinear dynamic macro-element for demand assessment of bridge substructures subjected to ship collision

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第11期12卷 826-836页

作者： Wei FAN wan-cheng YUAN Mi ZHOU IState Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China 2Department of Civil Engineering Purdue University West Lafayette 47907 USA Key Laboratory for Old Bridge Detection and Reinforcement Technology of Ministry of Transportation Chang＇an University Xi ＇an 710064 China

For the dynamic demand assessment of bridge structures under ship impact loading,it may be prudent to adopt analytical models which permit rapid analysis with reasonable ***,a nonlinear dynamic macro-element is proposed and implemented to quantify the demand of bridge substructures subjected to ship *** the proposed nonlinear macro-element,a combination of an elastic-plastic spring and a dashpot in parallel is employed to describe the mechanical behavior of ship-bows with strain rate *** on the analytical model using the proposed macro-element,a typical substructure under 5000 deadweight tonnage(DWT) ship collision is *** analyses indicate that the responses of the structure using the nonlinear macro-element agree with the results from the high resolution model,but the efficiency and feasibility of the proposed method increase significantly in practical ***,comparisons between some current design codes(AASHTO,JTGD60-2004,and TB10002.1-2005) and the developed dynamic analysis method suggest that these design codes may be improved,at least to consider the effect of dynamic amplification on structural demand.

关键词： Nonlinear macro-element Ship-bridge collision P-a curve Dynamic demand Design codes

酱酒1、2轮次窖池不同醅层微生态结构与酸性化合物组成解析及其相关性预测

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食品科学 2024年第4期45卷 88-95页

作者：万旗钰程玉鑫黄永光佘荣书邓昌伟左乾程贵州大学酿酒与食品工程学院贵州省发酵工程与生物制药重点实验室贵州贵阳550025 贵州省酣客君丰酒业有限公司贵州仁怀564500

以酱香白酒酿造过程中1、2轮次上、中、底层窖池酒醅为研究对象,采用高通量测序技术偶联超高效液相色谱等方法解析酒醅中微生物群系结构、酸类化合物结构及其酸类化合物分布与微生物群系相关性,进一步揭示其内在机制。结果表明,2轮次酒... 详细信息

以酱香白酒酿造过程中1、2轮次上、中、底层窖池酒醅为研究对象,采用高通量测序技术偶联超高效液相色谱等方法解析酒醅中微生物群系结构、酸类化合物结构及其酸类化合物分布与微生物群系相关性,进一步揭示其内在机制。结果表明,2轮次酒醅总酸含量大于1轮次;7种酸类化合物在窖池不同时空径向的分布规律不同;1、2轮次酒醅中乳酸和乙酸含量占比较大。1、2轮次绝对优势细菌属为Limosilactobacillus,优势真菌属为Saccharomyces和Candida,且随发酵时间延长,微生物群系结构差异显著。总酸和酸类化合物含量与Limosilactobacillus、Schizosaccharomyces、Zygosaccharomyces、Candida和Kazachstania相对丰度呈正相关,与Lactobacillus、Saccharomyces、Paecilomyces和Torulaspora相对丰度呈负相关。本研究揭示了酱香白酒1、2轮次窖池酒醅不同时空径向的酸度及酸类化合物与微生物群落间的相关性,可为进一步阐明酱香白酒窖池发酵机理提供理论参考。

关键词：酱香型白酒酒醅酸类化合物微生物群落相关性

Numerical simulations of multi-layer-liquid sloshing by multiphase MPS method

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Journal of Hydrodynamics 2021年第5期33卷 938-949页

作者： Xiao Wen Wei-wen Zhao De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this paper,a multiphase moving particle semi-implicit(MPS)method is developed by introduction of various multiphase models into the original MPS method for single-phase flows,and is then applied to the numerical simulations of two-layer-liquid and three-layer-liquid sloshing in a 2-D rectangular tank under different external *** validate the accuracy of the present multiphase MPS method,the qualitative and quantitative results,including wave profiles,interface elevations and impact pressures,are compared with experimental data and other numerical results,which show a good *** particular,the evolutions of free surface and phase interfaces are compared and an obvious discrepancy is found,indicating that the phase interfaces may suffer from complex deformations while the free surface keeps relatively ***,the different modes of phase interface are observed under different excitation ***,the violent sloshing of a three-layer-liquid system is simulated and the phenomenon of internal wave breaking is well captured,which mainly benefitted from the Lagrangian basis of MPS method and its advantage in multiphase flows with complex ***,the three-layer-liquid sloshing with a vertical baffle are simulated to investigate the suppressing effect of baffle on multi-layer-liquid sloshing.

关键词： Moving particle semi-implicit(MPS) multiphase flows multi-layer-liquid liquid sloshing

PopFlow:a novel flow management scheme for SDN switch of multiple flow tables based on flow popularity

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Frontiers of Computer Science 2020年第6期14卷 111-122页

作者： cheng wanG Kyung Tae KIM hee Yong YOUN College of Electrical and Computer Engineering Sungkyunkwan UniversitySuwon 16419Korea College of Software Sungkyunkwan UniversitySuwon 16419Korea

Pipeline processing is applied to mutiple flow tables(MFT)in the switch of software-defined network(SDN)to increase the throughput of the ***,the processing time of each flow increases as the size or number of flow tables gets *** this paper we propose a novel approach called PopFlow where a table keeping popular flow entries is located up front in the pipeline,and an express path is provided for the flow matching the table.A Markov model is employed for the selection of popular entries considering the match latency and match frequency,and Queuing theory is used to model the flow processing time of the existing MFT-based schemes and the proposed *** simulation reveals that the proposed scheme substantially reduces the flow processing time compared to the existing schemes,and the diference gets more significant as the flow arrival rate increases.

关键词： edge computing SDN pipeline processing PopFlow match frequency and latency markov model-based prediction

Kidney injury molecule-1:a novel entry factor for SARS-CoV-2

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Journal of Molecular Cell Biology 2021年第3期13卷 159-160页

作者： cheng wan Chun Zhang Department of Nephrology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Renal involvement occurs frequently among patients with coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),and acute kidney injury(AKI)is associated with poor prognosis and mortality of *** potential mechanisms of AKI include direct virulence of SARS-CoV-2 and indirect mechanisms such as hyperinflammation,hypercoagulation,and unspecific kidney injury factors(Gabarre et al.,2020).

关键词： acute Kidney involvement