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Hitching a ride to the top:peroxisomes fuel cilium with cholesterol

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Science China(Life Sciences) 2021年第3期64卷 478-481页

作者： Jie Luo yuan-bin liu Bao-Liang Song Hubei Key Laboratory of Cell Homeostasis College of Life SciencesWuhan UniversityWuhan 430072China

Primary cilium,which protrudes from the cell,is a microtubule-based structure ensheathed by a highly specialized plasma membrane(PM).It serves as a signaling hub for sensing and transducing various external stimuli including fluids,light,odorants as well as extracellular *** various signal transduction pathways that act through the primary cilium,the Hedgehog(Hh)pathway draws the most attention owing to its essential role in vertebrate development and its intimate link to carcinogenesis(Bangs and Anderson,2017).The major components of the Hh pathway include the secreted ligand Hh,two transmembrane proteins Patched(Ptch)and Smoothened(Smo),and the transcription factor glioma-associated oncogene(Gli).Ptch is the receptor for Hh which,in the absence of Hh,resides at the primary cilium and prevents ciliary localization and activation of *** Hh binding,however,Ptch is suppressed and displaced from the ciliary *** permits Smo to enter the primary cilium and initiate a cascade of events that lead to the activation of Gli transcription factors and transcription of downstream target genes.

关键词： ilium carcinogenesis specialized

Simultaneous measurement of distance and speed using frequency-modulated continuous-wave self-mixing interferometry and all-phase fast Fourier transform

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Chinese Optics Letters 2024年第7期22卷 29-34页

作者： Jinyuan yuan bin liu School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China SECTE University of WollongongWollongong NSW 2522Australia

In this work,we propose a method using frequency-modulated continuous-wave(FMCW)self-mixing interferometry(SMI)and all-phase fast Fourier transform(APFFT)for simultaneous measurement of speed and *** offers superior accuracy in frequency determination by mitigating issues like the fence effect and spectrum leakage,contributing to the high-accuracy measurement for speed and *** simulations and experiments have demonstrated relative errors at the levels of 10^(−4) and 10^(−3) for distance and speed measurements,***,factors impacting measurement performance have been *** proposed method provides a high-performance and cost-effective solution for distance and speed measurements,applicable across scientific research and various industrial domains.

关键词： self-mixing interferometry frequency-modulated continuous-wave interferometry all-phase fast Fourier transform measurement of distance and speed.

Linear/branched Block Polyethylene Produced by a-Diimine Nickel(Ⅱ)Catalyst and Bis(phenoxy-imine)Zirconium binary Catalyst System in the Presence of Diethyl Zinc

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Chinese Journal of Polymer Science 2021年第12期39卷 1581-1589页

作者： Ding-Ding Zhao Yan-Hui Hou Ke-Ning Zong Mi-Mi Cui bin-yuan liu Min Yang Hebei Key Laboratory of Functional Polymers Institute of Polymer Science and EngineeringHebei University of TechnologyTianjin 300130China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin 300160China

In order to promote development of linear/branched block polyethylenes based on new catalytic systems,we synthesized a novel *** nickel(Ⅱ)complex with isopropyl substituents on ortho-N-aryl and hydroxymethyl phenyl substituents on para-Naryl *** activity of a-dimine nickl(Ⅱ)catalyst was 3.02x10^(6)g-mol_(ni)^(-1)·h^(-1) at 70℃,and resultant polyethylene possessed 135/1000C *** linear/branched block polyethylenes were synthesized from ethylene polymerization catalyzed by the a-dimine nicke(Ⅱ)complex/bis(phenoxy-imine)zirconium in the presence of diethyI *** the addition of ZnEtz(from 0 to 400),the melting peak of resultant polyethylene changed from a single melting peak to bimodal melting *** molecular weights of resultant polyethylene ranging from 26.8 kg/mol to 17.1 kg/mol and PDI values varying gradually from 24.4 to 15.2 were obtained vla adjusting ZnEt;*** molar ratio of two *** addition,the branching degree of the polyethylene increased from 13/1000C to 56/1000 with the increase of the proportion of a dimine nickel(Ⅱ)*** this binary catalyst system,the reaction temperature of chain shutting polymerization can be carried out at 70℃,which is more conducive to industrial application.

关键词： Chain shuttling polymerization Linear/branched block polyethylene a-Diimine nickel Bis(phenoxy-imine)zirconium Ethylene

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin yuan Lin ZHOU Jia-sheng liu Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

Dewetting Kinetics of Thin Polymer Films with Different Architectures:Effect of Polymer Adsorption

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Chinese Journal of Polymer Science 2018年第8期36卷 984-990页

作者： Li-Na Wang Huan-Huan Zhang Lin Xu bin-yuan liu Tong-Fei Shi Shi-Chun Jiang Li-Jia An School of Materials Science and Engineering Tianjin University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Laboratory of Surface Physics and Chemistry Guizhou Education University Department of Polymer Science and Engineering Hebei University of Technology

We have investigated the influence of the adsorption process on the dewetting behavior of the linear polystyrene film （LPS）, the 3-arm star polystyrene film （3SPS） and the ring polystyrene film （RPS） on the silanized Si substrate. Results show that the adsorption process greatly influences the dewetting behavior of the thin polymer films. On the silanized Si substrate, the 3SPS chains exhibit stronger adsorption compared with the LPS chains and RPS chains; as a result, the wetting layer forms more easily. For LPS films, with the decrease of annealing temperature, the kinetics of polymer film changes from exponential behavior to slip dewetting. As a comparison, the stability of 3SPS and RPS films switches from slip dewetting to unusual dewetting kinetic behavior. The adsorbed nanodroplets on the solid substrate play an important role in the dewetting kinetics by reducing the driving force of dewetting and increase the resistant force of dewetting. Additionally, Brownian dynamics （BD） simulation shows that the absolute values of adsorption energy （ε） gradually increase from linear polymer （-0.3896） to ring polymer （-0.4033） and to star polymer （-0.4264）, which is consistent with the results of our adsorption experiments.

关键词： Thin polymer film Star polystyrene Ring polystyrene Dewetting Adsorption

Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： bin Wang yuan Lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Thermostable α-Diimine Nickel Complexes with Substituents on Acenaphthequinone-backbone for Ethylene Polymerization

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Chinese Journal of Polymer Science 2020年第11期38卷 1214-1220,I0007页

作者： Rui-Fang Zhang Yan-Hui Hou Xu-Ling Wei Ding-Ding Zhao Mi-Mi Cui Fei-Fan Zhai Xiang-liu Li bin-yuan liu Min Yang Hebei Key Laboratory of Functional Polymers Tianjin Key Laboratory of Chemical Process SafetyInstitute of Polymer Science and EngineeringHebei University of TechnologyTianjin 300130China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin 300160China Lanzhou Petrochemical Research Center Petrochemical Research Institute of CNPCLanzhou 730060China

In order to promote the thermostability of a-diimine nickel complex by ligand backbone structure,a series of α-diimine nickel complexes with substituents on acenaphthequinone backbone were synthesized and used as catalysts for ethylene *** the hydroxyethyl phenoxyl group was introduced to the acenaphthequinone-backbone,the thermal stability and activity of the catalyst could be significantly *** catalytic activity of complex C2[5-(4-(2-hydroxyethyl)phenoxyl)-N,N-bis(2,6-diisopropyl)acenaphthylene-1,2-diimine]nickel(Ⅱ)dibromide with isopropyl substituents on N-aryl reached 8.2×10^6g/(molNi·h)at 70℃and 2 *** activity of[5-(4-(2-hydroxyethyl)phenoxyl)-N,N-bis(2,6-dibenzhydryl-4-menthylphenyl)acenaphthylene-1,2-diimine]nickel(Ⅱ)dibromide(C3)still maintained at 6.7×10^5 g/(molNi·h)at 120℃.Compared with C3 containing bulky dibenzhydryl substituents,the activity of C2 was sensitive to the change of the polymerization ***,the polyethylenes obtained from complex C3 had lower branching ***,the molecular weight could reach 971 kg/mol,which is almost 5 times as much as that of the polyethylene obtained from complex C2.

关键词： α-Diimine nickel Ethylene polymerization Thermostability Ligand backbone structure

Cross-diffusion induced Turing instability of Hopf bifurcating periodic solutions in the reaction-diffusion enzyme reaction model

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International Journal of Biomathematics 2024年第4期17卷 133-150页

作者： Haicheng liu Wenshuo yuan bin Ge Jihong Shen College of Mathematical Sciences Harbin Engineering University Harbin 150001 HeilongjiangP.R.China

Aiming at the spatial pattern phenomenon in biochemical reactions,an enzyme-reaction Sporns-Seelig model with cross-diffusion is chosen as study *** the central manifold theory,normal form method,local Hopf bifurcation theorem and perturbation theory,we study Turing instability of the spatially homogeneous Hopf bifurcation periodic *** last,the theoretical results are verified by numerical simulations.

关键词： Sporns-Seelig model diffusion Hopf bifurcation periodic solutions Turing instability

Multidomain Hybrid Direct DG and Central Difference Methods for Viscous Terms in Hyperbolic-Parabolic Equations

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 1-36页

作者： Weixiong yuan Tiegang liu bin Zhang Kui Cao Kun Wang LMIB and School of Mathematical Sciences Beihang UniversityBeijing 100191China

A class of multidomain hybrid methods of direct discontinuous Galerkin(DDG)methods and central difference(CD)schemes for the viscous terms is pro-posed in this *** conservative and nonconservative coupling modes are *** treat the shock wave,the nonconservative coupling mode automatically switch to conservative coupling mode to preserve the conservative property when discontinuities pass through the artiﬁcial *** maintain the accuracy of the hybrid methods,the Lagrange interpolation polynomials and their derivatives are reconstructed to handle the coupling cells in the DDG subdomain,while the values of ghost points for the CD subdomain are calculated by the approximate polynomials from the DDG *** linear stabilities of these methods are demonstrated in detail through von-Neumann *** multidomain hybrid DDG and CD meth-ods are then extended to one-and two-dimensional hyperbolic-parabolic *** results validate that the multidomain hybrid methods are high-order ac-curate in the smooth regions,robust for viscous shock simulations and capable to save computational cost.

关键词： Direct discontinuous Galerkin central difference schemes multidomain hybrid methods viscous terms hyperbolic-parabolic equations