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Quantum Algorithm for Boolean Equation Solving and Quantum Algebraic Attack on Cryptosystems

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Journal of Systems Science & Complexity 2022年第1期35卷 373-412页

作者： chen yu-ao Gao Xiao-Shan Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

This paper presents a quantum algorithm to decide whether a Boolean equation system F has a solution and to compute one if F does have solutions with any given success *** runtime complexity of the algorithm is polynomial in the size of F and the condition number of certain Macaulay matrix associated with *** a consequence,the authors give a polynomial-time quantum algorithm for solving Boolean equation systems if their condition numbers are polynomial in the size of *** authors apply the proposed quantum algorithm to the cryptanalysis of several important cryptosystems:The stream cipher Trivum,the block cipher AES,the hash function SHA-3/Keccak,the multivariate public key cryptosystems,and show that they are secure under quantum algebraic attack only if the corresponding condition numbers are *** leads to a new criterion for designing such cryptosystems which are safe against the attack of quantum computers:The corresponding condition number.

关键词： Block cipher AES Boolean equation solving condition number hash function SHA3/Keccak HHL algorithm MPKC polynomial system solving quantum algorithm stream cipher Trivum

Laureatcs of TKK Young Scientist Awards 2016

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Bulletin of the Chinese Academy of Sciences 2016年第2期30卷 77-79页

作者： chen yu'ao

Under the mentorship of Prof. PAN Jianwei, chen received his master＇s degree from the University of Science and Technology of China （USTC） in 2004 and his Ph.D. degree from the University of Heidelberg in 2008. He then joined the QUANTUM group at the University of Mainz as a postdoctoral researcher and subsequently moved with the group to Max- Planck Institute for Quantum Optics and the Ludwig- Maximilians University,

关键词：青年科学家中国科技大学博士学位硕士学位量子光学潘建伟海德堡研究员

Di-and tri-methylation of histone H3K36 play distinct roles in DNA double-strand break repair

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Science China(Life Sciences) 2024年第6期67卷 1089-1105页

作者： Runfa chen Meng-Jie Zhao yu-Min Li ao-Hui Liu Ru-Xin Wang yu-Chao Mei Xuefeng chen Hai-Ning Du Hubei Key Laboratory of Cell Homeostasis College of Life SciencesTaiKang Center for Life and Medical SciencesFrontier Science Center for Immunology and MetabolismHubei Clinical Research Center of Emergency and ResuscitationEmergency Center of Zhongnan HospitalWuhan UniversityWuhan 430072China Hubei Key Laboratory of Cell Homeostasis College of Life SciencesTaiKang Center for Life and Medical SciencesFrontier Science Center for Immunology and MetabolismWuhan UniversityWuhan 430072China

Histone H3 Lys36(H3K36)methylation and its associated modifiers are crucial for DNA double-strand break(DSB)repair,but the mechanism governing whether and how different H3K36 methylation forms impact repair pathways is ***,we unveil the distinct roles of H3K36 dimethylation(H3K36me2)and H3K36 trimethylation(H3K36me3)in DSB repair via non-homologous end joining(NHEJ)or homologous recombination(HR).Yeast cells lacking H3K36me2 or H3K36me3 exhibit reduced NHEJ or HR efficiency.y Ku70 and Rfa1 bind H3K36me2-or H3K36me3-modified peptides and chromatin,*** these interactions impairs y Ku70 and Rfa1 recruitment to damaged H3K36me2-or H3K36me3-rich loci,increasing DNA damage sensitivity and decreasing repair ***,H3K36me2-enriched intergenic regions and H3K36me3-enriched gene bodies independently recruit y Ku70 or Rfa1 under DSB ***,human KU70 and RPA1,the homologs of y Ku70 and Rfa1,exclusively associate with H3K36me2 and H3K36me3 in a conserved *** findings provide valuable insights into how H3K36me2 and H3K36me3 regulate distinct DSB repair pathways,highlighting H3K36 methylation as a critical element in the choice of DSB repair pathway.

关键词： histone H3K36 methylation Ku70 RPA non-homologous end joining homologous recombination

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Spray pyrolysis-derived W-doped MoSe_(2)/rGO paper-like microspheres:optimization of microstructure and mesostructure for enhanced lithium storage

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Rare Metals 2024年第7期43卷 3019-3031页

作者： Wei Wang Jun-yu chen Jie Ouyang Hong Yin ao-Jie Li Liang chen Jun-Lin Huang yu-Can Zhu Gang-Yong Li Zhao-Hui Hou Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and TechnologyYueyang 414006China School of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang414006China Hunan Province Key Laboratory of Materials Surface&Interface Science and Technology Material Science and Engineering SchoolCentral South University of Forestry and TechnologyChangsha 410004China International Iberian Nanotechnology Laboratory(INL) AvMestre Jose Veiga4715-330 BragaPortuga

Two-dimensional MoSe_(2) is a promising candidate for lithium-ion battery ***,its conductivity and lithium storage volumetric effect still need to be *** this work,W-doped MoSe_(2)/rGO paper-like microspheres are successfully prepared through ultrasonic spray pyrolysis,achieving optimization at both the microstructure and mesostructure to enhance the lithium storage performance of the ***,by utilizing the similar two-dimensional structure between MoSe_(2) and rGO,self-assembly is achieved through spray pyrolysis,resulting in a well-defined van der Waals heterostructure at the interface on the microscale,enhancing the electron and ion transfer capability of the ***,the mesoscale paper-like microsphere morphology provides additional volume expansion buffering ***,W-doping not only increases the interlayer spacing of MoSe_(2)(0.73 nm),thereby reducing the diffusion resistance of Li+,but also allow for the modulation of the energy band structure of the *** functional theory(DFT)calculations confirm that W-doped MoSe_(2)/rGO exhibits the narrowest bandgap(0.892 eV).Therefore,the composite demonstrates excellent lithium storage performance,maintaining a specific capacity of 732.9 mAh·g^(-1)after 300 cycles at a current density of 1 A·g^(-1).

关键词： Molybdenum selenide Heterostructure Microspheres Li-ion batteries Kinetics

Polyolefin vitrimers bearing acetoacetate functionality

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Science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang yue Liu Wenmin Pang ao chen Min chen Chinese Academy of Sciences (CAS) Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization

Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： yu Zhang Hong-yu Zhang Ran Xia Si-ao Jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

Cluster-Based Massive Access for Massive MIMO Systems

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China Communications 2024年第1期21卷 24-33页

作者： Shiyu Liang Wei chen Zhongwen Sun ao chen Bo Ai State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong UniversityBeijing 100091China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100091China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong UniversityBeijing 100091China Key Laboratory of Railway Industry of Broadband Mobile Information Communications Beijing Jiaotong UniversityBeijing 100091China Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing Jiaotong UniversityBeijing 100091China School of Information Engineering Zhengzhou UniversityZhengzhou 450001China

Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in *** this paper,a novel cluster-based massive access method is proposed for massive multiple input multiple output *** exploiting the angular domain characteristics,devices are separated into multiple clusters with a learned cluster-specific dictionary,which enhances the identification of active *** detected active devices whose data recovery fails,power domain nonorthogonal multiple access with successive interference cancellation is employed to recover their data via *** results show that the proposed scheme and algorithm achieve improved performance on active user detection and data recovery.

关键词： compressive sensing dictionary learning multiuser detection random access

Flavor mixing and solution structures in Dyson–Schwinger equations for a two-flavor system

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Communications in Theoretical Physics 2024年第10期76卷 64-77页

作者： Xue-ao Chao yu-xin Liu Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Collaborative Innovation Center of Quantum Matter Center for High Energy Physics Peking University

We solved the Dyson–Schwinger(DS) equations for a two-flavor system with symmetry to study its flavor mixing effects. Initially, we employed the point interaction model and bare vertex approximation to reveal the structure of the solutions. Using the point interaction model, the DS equations can be solved analytically, and we found that these solutions can be classified into three groups, each forming an ellipse. These solutions exhibit SO(2) symmetry, while the original SU(2)symmetry at the Lagrangian level is dynamically broken to SO(2), corresponding to the emergence of flavor mixing effects. However, this flavor mixing effect does not manifest in the final physical *** utilizing the system's SO(2) symmetry, we can diagonalize the propagators of the DS equations,eliminating the flavor mixing effect but causing the originally degenerate masses at the Lagrangian level to split. These mass eigenstates have identical quantum numbers but different masses. If we can correspond these to quark particles of different generations, we can explain why the three generations of quarks have different masses and obtain the corresponding quark mass spectrum. Finally, we provide the corresponding numerical results using a more realistic interaction model.

关键词： dynamic symmetry breaking Dyson-Schwinger equation flavor change mass splitting

Original article： Arthroscopic treatment for osteochondral lesions of the talus： analysis of outcome predictors

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Chinese Medical Journal 2010年第3期 296-300页

作者： GUO Qin-wei HU yue-lin JIao chen yu Chang-long ao Ying-fang Institute of Sports Medicine Peking University Third Hospital Beijing 100191 China

Background Compared with traditional arthrotomy procedures, arthroscopic treatment for osteochondral lesions of the talus has some advantages. However, there has been considerable debate about the outcome predictors for this surgical technique. This study aimed to investigate the outcomes of arthroscopic treatment for osteochondral lesions of the talus, and analyze its outcome predictors. Methods Clinical data of 48 patients with osteochondral lesions of the talus who underwent ankle arthroscopy were studied. Arthroscopic debridement was performed on all patients, and microfracture was also performed in 36 cases. Scores on a subjective satisfaction questionnaire, visual analog scale （VAS） for pain, and the American Orthopedic Foot ＆ Ankle Society （aoFAS） ankle and hindfoot scores were obtained before and after surgery. Results Five patients lost to follow up. The other forty-three patients, 8 of whom were athletes, were followed up for an average of 23.9 months. The average aoFAS post-operative score was 90.16±9.96, compared with 70.81±6.96 before surgery （t=9.353, P 〈0.001）. The VAS pain score after the operation （2.51±2.45） was significantly lower than that before the operation （6.95±.40）（t=8.647, P 〈0.001 ）. Of the 43 patients, 35 （81.4%） had good or excellent results. There was no significant difference in outcome between the medial and lateral groups （z=0.205, P=0.838）, while a better outcome was found with lesions smaller than 10 mm than those with larger lesions （z=2.199, P=0.028）. Age, sex, athletic profession and location of the lesion did not significantly correlate with outcomes. Conclusions Arthroscopic treatment is effective and safe for osteochondral lesions of the talus. A strong correlation was found between the size of the lesion and successful outcome.

关键词： osteochondral lesion talus arthroscopy