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The Important Roles of Water in Protein Folding:an Approach by Single Molecule Force Spectroscopy

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Chinese Journal of Polymer Science 2018年第3期36卷 379-384页

作者： bo cheng Shu-xun Cui School of Mechanical Engineering North University of ChinaTaiyuan 030051China Key Lab of Advanced Technologies of Materials Ministry of Education of ChinaSouthwest Jiaotong UniversityChengdu 610031China

The single-chain elasticity of a completely unfolded protein （027）8, modules of human cardiac titin） is studied in different liquid environments by the atomic force microscopy （AFM）-based single molecule force spectroscopy （SMFS）. The experimental results show that there is a clear deviation between the force curves obtained in the aqueous and nonaqueous environments. Such a deviation can be attributed to the additional energy consumed by the rearrangement of the bound water molecules around the chain of the completely unfolded （I27）s chain upon stretching in aqueous solution, which is very similar to the partial dehydration process from a denatured/unfolded to a native/folded protein. Through the analysis of the free energy changes involved in protein folding, we conclude that it is due to the weak disturbance of water molecules and the special backbone structures of proteins that the self-assembly of proteins can be achieved in physiological conditions. We speculate that water is likely to be an important criterion for the selection of self-assembling macromolecules in the prebiotic chemical evolution.

关键词： SMFS Protein Folding Water

Experimental Study on the Wavelengths of Two-Dimensional and Three-Dimensional Freak Waves

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China Ocean Engineering 2023年第1期37卷 154-164页

作者： CUI cheng PAN Wen-bo National Engineering Research Center for Port Hydraulic Construction Technology M.O.T.Tianjin Research Institute of Water Transport EngineeringTianjin 300456China

Freak waves are commonly characterized by strong-nonlinearity, and the wave steepness, which is calculated from the wavelength, is a measure of the degree of the wave nonlinearity. Moreover, the wavelength can describe the locally spatial characteristics of freak waves. Generally, the wavelengths of freak waves are estimated from the dispersion relations of Stokes waves. This paper concerns whether this approach enables a consistent estimate of the wavelength of freak waves. The two-(unidirectional, long-crested) and three-dimensional(multidirectional, shortcrested) freak waves are simulated experimentally through the dispersive and directional focusing of component waves, and the wavelengths obtained from the surface elevations measured by the wave gauge array are compared with the results from the linear, 3rd-order and 5th-order Stokes wave theories. The comparison results suggest that the 3rd-order theory estimates the wavelengths of freak waves with higher accuracy than the linear and 5th-order theories. Furthermore, the results allow insights into the dominant factors. It is particularly noteworthy that the accuracy is likely to depend on the wave period, and that the wavelengths of longer period freak waves are overestimated but the wavelengths are underestimated for shorter period ones. In order to decrease the deviation, a modified formulation is presented to predict the wavelengths of two-and three-dimensional freak waves more accurately than the 3rd-order dispersion relation, by regression analysis. The normalized differences between the predicted and experimental results are over 50% smaller for the modified model suggested in this study compared with the 3rd-order dispersion relation.

关键词： freak wave rogue wave wavelength three-dimension directional spread multidirectional wave

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： xu Jian-Qiang MA Zhao-Peng cheng Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

SOME INVERSE OPTIMIZATION PROBLEMS ON NETWORK

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Journal of Systems Science & Complexity 2013年第3期26卷 350-364页

作者： xu cheng xu Xiaoming School of Management University of Shanghai for Science and Technology College of Mathematics Qingdao University

In this paper,the authors consider some inverse problems on network,such as the inverse transport problems with gains(IGTP) and the inverse linear fractional minimum cost flow problem(IFFP).Firstly,the authors give the mathematics model of(IGTP) and an efficient method of solving it under l_1 norm;Secondly,taking advantage of the optimality conditions,the authors consider the(IFFP) and give a simple method of solving ***,an numerical example test is also developed.

关键词： Dual problem fractional minimum cost flow problem gain network inverse problem.

电针内关、神门穴对海洛因依赖者稽延性戒断症状疗效观察

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上海针灸杂志 2011年第12期30卷 804-806页

作者：梁艳黄寅程波许静宗蕾上海中医药大学附属岳阳中西医结合医院上海200437

目的观察和分析针刺不同穴位对海洛因依赖者稽延性戒断症状的干预效果,为科研、临床筛选针刺治疗海洛因依赖稽延性症状的特异穴位提供临床依据。方法将60例男性海洛因依赖者随机分为对照组、针刺1组、针刺2组,采用稽延性戒断症状评分量... 详细信息

目的观察和分析针刺不同穴位对海洛因依赖者稽延性戒断症状的干预效果,为科研、临床筛选针刺治疗海洛因依赖稽延性症状的特异穴位提供临床依据。方法将60例男性海洛因依赖者随机分为对照组、针刺1组、针刺2组,采用稽延性戒断症状评分量表和汉密尔顿焦虑量表观察各组患者治疗前、治疗过程中及治疗3星期后的变化。结果针刺1组、针刺2组在控制稽延性戒断症状上与对照组相比有统计学差异(P0.05)。结论针刺可有效缓解海洛因依赖者稽延期戒断症状和精神焦虑症状;治疗海洛因依赖者稽延期诸症时,内关穴与神门穴具有同样显著疗效,并且神门穴对于心神的异常具有更快更好的显效趋势。

关键词：电针穴,内关穴,神门物质禁断综合征海洛因依赖

Gluing Affine Vortices

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Acta Mathematica Sinica,English Series 2024年第1期40卷 250-312页

作者： Guang bo xu Department of Mathematics Rutgers UniversityHill Center-Busch Campus 110 Frelinghuysen RoadPiscatawayNJ 08854-8019USA

We provide an analytical construction of the gluing map for stable affine vortices over the upper half plane with the Lagrangian boundary *** result is a necessary ingredient in studies of the relation between gauged ... 详细信息

关键词： Affine vortices gauged linear sigma model adiabatic limit symplectic reduction

Multiple Positive Solutions for Semi-positone m-point boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 419-426页

作者： cheng-bo Zhai cheng Yang School of Mathematical Science Shanxi University Shanxi 030006 China Business College of Shanxi University Shanxi 030031 China

In this article, we establish the existence of at least two positive solutions for the semi-positone m-point boundary value problem with a parameter u （t）＋ λf （t, u） = 0, t ∈ （0, 1）, u （0） = sum （biu （ξ i ）） from i=1 to m-2, u（1）= sum （aiu（ξ i ）） from i=1 to m-2, where λ 〉 0 is a parameter, 0 〈 ξ 1 〈 ξ 2 〈 ··· 〈 ξ m 2 〈 1 with 0 〈sum ai from i=1 to m-2 〈 1, sum bi from i=1 to m-2 =1 b i 〈 1, a i , b i ∈ [0, ∞） and f （t, u） ≥ M with M is a positive constant. The method employed is the Leggett-Williams fixed-point theorem. As an application, an example is given to demonstrate the main result.

关键词： Multiple positive solutions cone semi-positone m-point boundary value problem,concave functional parameter

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun xu Yue Li Jun Sun Shuyuan Du Xinpeng Di Yuguang Yang bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

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Construction and validation of prognostic model based on autophagy-related lncRNAs in gastric cancer

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BIOCELL 2022年第1期46卷 97-109页

作者： MENGQIU cheng WEI CAO GUODONG CAO XIN xu bo CHEN Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei230022China Anhui Medical University Hefei230022China

Gastric cancer(GC)is one of the most common cancer *** emerging evidence indicates that autophagy-related long non-coding RNA(lncRNA)plays an important role in the progression of GC,the prognosis of GC based on autophagy is still *** Cancer Genome of Atlas stomach adenocarcinoma(TCGA-STAD)dataset was downloaded and separated into a training set and a testing set ***,24 autophagy-related lncRNAs were found strongly associated with the survival of the TCGA-STAD dataset.11 lncRNAs were selected to build the risk score model through the least absolute shrinkage and selection operator(LASSO)*** patient got a risk score(RS),and patients were separated into a high-risk group and a low-risk group due to the median *** multivariate Cox analysis showed that the RS could be an independent prognosis *** Kaplan-Meier survival analysis and the Receiver Operating Characteristic(ROC)curve indicated the model had an excellent prediction *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis revealed that the mRNAs in the prognostic network were mainly involved in the autophagy and ubiquitin-like protein ligase *** Set Enrichment Analysis(GSEA)analysis uncovered that the differentially expressed genes(DEGs)in the high-risk group partially participated in the ECM receptor interaction and other signaling *** results indicated that the risk score model based on the autophagy-related lncRNAs performed well in the prediction of prognosis for patients with GC.

关键词： Gastric cancer Prognosis Autophagy Nomogram Long non-coding RNAs