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Supercoiled DNA Minicircles under Double-strand Breaks

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Chinese Journal of Polymer Science 2024年第9期42卷 1353-1359,I0007页

作者： Ye-Peng Qiao Chun-lai Ren National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China

Understanding how supercoiled DNA releases intramolecular stress is essential for its functional ***,the molecular mechanism underlying the relaxation process remains insufficiently *** we employed MD simulations based on the oxDNA2 model to investigate the relaxation process of a 336-base pair supercoiled minicircular DNA under double-strand breaks with two fixed *** simulations show that the conformational changes in the DNA occur continuously,with intramolecular stress release happening abruptly only when the DNA chain traverses the breakage *** relaxation process is influenced not only by the separation distance between the fixed ends but also their ***,we observe an inhibitory effect on the relaxation characterized by small angles,where short terminal loops impede DNA conformational adjustments,preserving the supercoiled *** findings elucidate the intricate interplay between DNA conformational change,DNA motion and intramolecular stress release,shedding light on the mechanisms governing the relaxation of supercoiled DNA at the molecular level.

关键词： Supercoiled DNA DNA minicircle DNA relaxation oxDNA model MD simulation

Nanostructured Mn-based oxides as high-performance cathodes for next generation Li-ion batteries

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Journal of Energy Chemistry 2021年第8期30卷 547-571,I0012页

作者： Guodong Hao Qinzhi lai Hongzhang Zhang School of Chemistry and Chemical Engineering Mudanjiang Normal UniversityMudanjiang 157011China Department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China Division of Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Mn-based oxides have been regarded as a promising family of cathode materials for high-performance lithium-ion batteries,but the practical applications have been limited because of severe capacity deterioration(such as Li Mn O_(2)and Li Mn_(2)O_(4))as well as further complications from successive structure changes during cycling,low initial coulombic efficiency(such as Li-rich cathode)and oxidization of organic carbonate solvents at high charge potential(such as Li Ni0.5 Mn1.5 O4).Large amounts of efforts have been concentrated on resolving these issues towards practical applications,and many vital progresses have been carried ***,the primary target of this review is focused on different proposed strategies and breakthroughs to enhance the rate performance and cycling stability of nanostructured Mn-based oxide cathode materials for Li-ion batteries,including morphology control,ion doping,surface coatings,composite *** combination of delicate architectures with conductive species represents the perspective ways to enhance the conductivity of the cathode materials and further buffer the structure transformation and strain during *** last,based on the elaborated progress,several perspectives of Mn-based oxide cathodes are summarized,and some possible attractive strategies and future development directions of Mn-based oxide cathodes with enhanced electrochemical properties are *** review will offer a detailed introduction of various strategies enhancing electrochemical performance and give a novel viewpoint to shed light on the future innovation in Mn-based oxide cathode materials,which benefits the design and construction of high-performance Mn-based oxide cathode materials in the future.

关键词： Mn-based oxide Cathode material Electrochemical property Modification

Epigenetic regulation of drug metabolism and transport

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Acta Pharmaceutica Sinica B 2015年第2期5卷 106-112页

作者： lai Peng Xiaobo Zhong Department of Pharmaceutical Sciences School of Pharmacy University of Connecticut Key Laboratory of System Biomedicine Center for Comparative Biomedicine Institute of Systems BiomedicineShanghai Jiao Tong University

The drug metabolism is a biochemical process on modification of pharmaceutical substances through specialized enzymatic systems. Changes in the expression of drug-metabolizing enzyme genes can affect drug metabolism. Recently, epigenetic regulation of drug-metabolizing enzyme genes has emerged as an important mechanism. Epigenetic regulation refers to heritable factors of genomic modifications that do not involve changes in DNA sequence. Examples of such modifications include DNA methylation, histone modifications, and non-coding RNAs. This review examines the widespread effect of epigenetic regulations on genes involved in drug metabolism, and also suggests a network perspective of epigenetic regulation. The epigenetic mechanisms have important clinical implications and may provide insights into effective drug development and improve safety of drug therapy.

关键词： Drug metabolism DNA methylation Epigenetics Histone modification Non-coding RNA Transporter

Manipulating metal-sulfur interactions for achieving high-performance S cathodes for room temperature Li/Na-sulfur batteries

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Carbon Energy 2021年第2期3卷 253-270页

作者： Ying-Ying Dai Chun-Mei Xu Xiao-Hao Liu Xiang-Xi He Zhuo Yang Wei-Hong lai Li Li Yun Qiao Shu-Lei chou School of Environmental and Chemical Engineering Shanghai UniversityShanghaiChina Institute for Superconducting&Electronic Materials Innovation CampusUniversity of WollongongWollongongNew South WalesAustralia

Rechargeable lithium/sodium-sulfur batteries working at room temperature(RT-Li/S,RT-Na/S)appear to be a promising energy storage system in terms of high theoretical energy density,low cost,and abundant resources in *** are,thus,considered as highly attractive candidates for future application in energy storage ***,the solubility of sulfur species,sluggish kinetics of lithium/sodium sulfide compounds,and high reactivity of metallic anodes render these cells *** a consequence,metal-sulfur batteries present low reversible capacity and quick capacity loss,which hinder their practical *** to address these issues regarding S cathodes are critical to the increase of their performance and our fundamental understanding of RT-Li/S and RT-Na/S battery ***-sulfur interactions,recently,have attracted considerable attention,and there have been new insights on pathways to high‐performance RT-Li/Na sulfur batteries,due to the following factors:(1)deliberate construction of metal-sulfur interactions can enable a leap in capacity;(2)metal-sulfur interactions can confine S species,as well as sodium sulfide compounds,to stop shuttle effects;(3)traces of metal species can help to encapsulate a high loading mass of sulfur with high‐cost efficiency;and(4)metal components make electrodes more *** this review,we highlight the latest progress in sulfide immobilization via constructing metal bonding between various metals and S ***,we summarize the storage mechanisms of Li/Na as well as the metal-sulfur interaction ***,the current challenges and future remedies in terms of intact confinement and optimization of the electrochemical performance of RT-Li/Na sulfur systems are discussed in this review.

关键词： electrochemical mechanism metal-sulfur interactions room temperature Li/Na sulfur batteries S-confinement strategy

Accountable attribute-based authentication with fine-grained access control and its application to crowdsourcing

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Frontiers of Computer Science 2023年第1期17卷 205-218页

作者： Peng LI Junzuo lai Yongdong WU College of Information Science and Technology Jinan UniversityGuangzhou 510632China

We introduce a new notion called accountable attribute-based authentication with fine-grained access control (AccABA), which achieves (i) fine-grained access control that prevents ineligible users from authenticating;(ii) anonymity such that no one can recognize the identity of a user;(iii) public accountability, i.e., as long as a user authenticates two different messages, the corresponding authentications will be easily identified and linked, and anyone can reveal the user’s identity without any help from a trusted third party. Then, we formalize the security requirements in terms of unforgeability, anonymity, linkability and traceability, and give a generic construction to fulfill these requirements. Based on AccABA, we further present the first attribute-based, fair, anonymous and publicly traceable crowdsourcing scheme on blockchain, which is designed to filter qualified workers to participate in tasks, and ensures the fairness of the competition between workers, and finally balances the tension between anonymity and accountability.

关键词： fine-grained access control anonymous authentication accountability fairness crowdsourcing blockchain

Regulation Method for Torque-Angle Characteristics of Rotary Electric-Mechanical Converter Based on Hybrid Air Gap

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 100-110页

作者： Bin Meng Yongjiang lai Xinguo Qiu Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of EducationZhejiang University of TechnologyHangzhouChina

The torque-angle characteristics of electric-mechanical converters are important determinants of the quality of electrohydraulic proportional control *** is far more difficult for a rotary electric-mechanical converter(REMC)to obtain flat torque-angle characteristics than traditional proportional solenoid,greatly influencing the promotion and application of rotary valves for electrohydraulic proportional control systems.A simple and feasible regulation method for the torque-angle characteristics of REMCs based on a hybrid air gap is *** regulation is performed by paralleling an additional axial air gap with the original radial air gap to obtain a flat torque-angle characteristic and increase output *** comparison,prototypes of REMCs based on hybrid and radial air gaps were manufactured,and a special test rig was *** torque-angle characteristics under different excitation currents and step responses were studied by magnetic circuit analysis,finite element simulation,and experimental *** experimental results were consistent with the theoretical *** was shown that REMCs based on a hybrid air gap can obtain a flat torque-angle characteristic with further optimizing of key structural parameters and also increase output *** regulation method provides a new approach for the design of proportional rotary electromechanical converters.

关键词： Rotary valve Rotary electric-mechanical converter Torque-angle characteristic Hybrid air gap Axial air gap Radial air gap

Epsilon-near-zero or mu-near-zero materials composed of dielectric photonic crystals

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Science China(Information Sciences) 2013年第12期56卷 148-157页

作者： LUO Jie lai Yun Wave-Functional Materials Lab Department of Physics Soochow University

We theoretically demonstrate that at certain frequencies two-dimensional dielectric photonic crystals(PCs)may be regarded as either epsilon-near-zero or mu-near-zero *** show that the transmission through a slab of such materials upon normal incidence is normally non-unity and decays with slab ***,when the incident angle increases slightly,the transmittance experiences a dramatic increase due to the Brewster *** combination of the tunneling and resonance efects makes such materials good candidates for almost perfect bending waveguides and cloaking in *** zero index also enables applications of focusing and directive *** last,the distinction between the single-zero and double-zero media is *** all of the above results,the numerical simulations perfectly match with theoretical predictions from the efective medium analysis.

关键词： photonic crystal epsilon-near-zero material mu-near-zero material efective medium transmission properties Brewster efect

A Sequential Partial Optimization Algorithm for Design of Near Linear-Phase IIR Digital Differentiators

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Chinese Journal of Electronics 2019年第5期28卷 968-977页

作者： MENG Hailong lai Xiaoping YI Huoping Key Lab for IOT and Information Fusion Technology of Zhejiang Hangzhou Dianzi University Institute of Information and Control Hangzhou Dianzi University

The linear phase is a major characteristic of digital differentiators in many signal processing applications. This study presents a sequential partial optimization method for designing a fullband infinite impulse response digital differentiator with a near linear phase. To achieve a near linear phase, the group delay is treated as an optimization variable, and the maximum phase error is minimized within a constrained *** each iteration of the algorithm, in addition to the whole numerator and group delay, only one secondorder denominator factor is optimized. The necessary and sufficient stability triangles are applied to insure the stability of the differentiators, and the Gauss-Newton strategy is used to handle the nonconvexity of the design problems. Design examples show that the proposed method outperforms several state-of-the-art methods in terms of the maximum phase deviation from the desired linear phase.

关键词： Digital differentiator Linear phase Sequential partial optimization Gauss-Newton strategy Mathematical programming

Study on microscale adhesion between solid surfaces with scanning probe

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Science China(Technological Sciences) 2013年第12期56卷 2934-2952页

作者： lai TianMao HUANG Ping School of Mechanical and Automotive Engineering South China University of Technology

The adhesion between two parallel solid surfaces is of great interest with the rapid development of micro-nano devices and *** adhesion forces between a flat tip with a diameter^1.7μm and some surface have been determined by recording the force-displacement curves with an atomic force microscope(AFM).The flat tip is used to prevent wear and mimic the adhesion between two parallel *** free energy of the solid surface is calculated by the contact angles between the probe liquids and the *** adhesion force between parallel solid surfaces cannot be predicted by the theory of thermodynamic surface free *** adhesion measurements were carried out under ambient conditions,in a nitrogen-filled glove box,under distilled water,and under potassium chloride(KCl)*** outcome shows that the real contact area without the applied load is only a small proportion of the apparent contact *** measurement stability and repeatability of adhesion by the AFM depend on the surface characterization,measurement methods and the *** different environments,there are different interactions and factors affecting the adhesion force,and the dominant interactions and factors may be different *** various interactions and factors are mutually coupled to determine the final adhesion force.

关键词： micro-scale adhesion force atomic force microscope force-displacement curve flat tip surface free energy