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Weighted Composition Operators from the Bloch Spaces to Weighted Hardy Spaces on Bounded Symmetric Domains

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Chinese Annals of Mathematics,Series B 2023年第2期44卷 289-298页

作者： Lei LI Xiao WANG School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China

Let BE be a bounded symmetric domain realized as the unit open ball of JB^(*)-triples.The authors will characterize the bounded weighted composition operator from the Bloch space B(BE)to weighted Hardy space Hv∞in terms of Kobayashi distance.The authors also give a sufficient condition for the compactness,and also give the upper bound of its essential norm.As a corollary,they show that the boundedness and compactness are equivalent for composition operator fromB(BE)to H∞(BE),when is a finite dimension JB^(*)-triple.Finally,they show the boundedness and compactness of weighted composition operators from B(BE)to Hv,0∞(BE)are equivalent when is a finite dimension JB^(*)-triple.

关键词： Weighted composition operators Bloch functions Holomorphic func-tions Bounded symmetric domains Kobayashi distance

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大足宝顶山石刻造像性质初探

敦煌学辑刊 2022年第1期1卷 105-115页

作者：雷玉华李春华西南民族大学旅游与历史文化学院四川成都610072 西南民族大学民族博物馆四川成都610072

目前许多学者认为,川渝安岳———大足地区分布着的一批佛教石刻造像是四川密宗造像,简称“川密”造像;其中最醒目的题材是柳本尊行化图,其核心区域就是大足宝顶山的大、小佛湾,教主是唐末五代的柳本尊、南宋的赵本尊。但从宝顶山石刻... 详细信息

目前许多学者认为,川渝安岳———大足地区分布着的一批佛教石刻造像是四川密宗造像,简称“川密”造像;其中最醒目的题材是柳本尊行化图,其核心区域就是大足宝顶山的大、小佛湾,教主是唐末五代的柳本尊、南宋的赵本尊。但从宝顶山石刻的内容看,更多是华严、禅宗、净土等雕刻,柳本尊的立雪断臂等修行方式也来自禅宗,铭文中“六代祖师传密印”也是指禅宗六祖。而且晚唐至宋,正是禅宗发展壮大、合并其它宗派的时期,立雪、断臂类修行故事也正流行,柳本尊正是活动在这个时间范围内。从图像内容、经文、铭文等各方面看,有理由认为柳本尊所传之法实为融合了华严、净土等思想的禅宗,赵智凤教派其实继自禅宗;至明清时期复兴之后,仍为禅宗。

关键词：宝顶山造像性质密宗禅宗

ENERGY AND QUADRATIC INVARIANTS PRESERVING METHODS FOR HAMILTONIAN SYSTEMS WITH HOLONOMIC CONSTRAINTS

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Journal of Computational Mathematics 2023年第1期41卷 107-132页

作者： Lei LI Dongling Wang School of Mathematical Sciences Institute of Natural SciencesMOE-LSCShanghai Jiao Tong UniversityShanghai 200240China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China

We introduce a new class of parametrized structure–preserving partitioned RungeKutta(α-PRK)methods for Hamiltonian systems with holonomic constraints.The methods are symplectic for any fixed scalar parameterα,and are reduced to the usual symplectic PRK methods like Shake-Rattle method or PRK schemes based on Lobatto IIIA-IIIB pairs whenα=0.We provide a new variational formulation for symplectic PRK schemes and use it to prove that theα-PRK methods can preserve the quadratic invariants for Hamiltonian systems subject to holonomic constraints.Meanwhile,for any given consistent initial values(p0,q0)and small step size h>0,it is proved that there existsα∗=α(h,p0,q0)such that the Hamiltonian energy can also be exactly preserved at each step.Based on this,we propose some energy and quadratic invariants preservingα-PRK methods.Theseα-PRK methods are shown to have the same convergence rate as the usual PRK methods and perform very well in various numerical experiments.

关键词： Hamiltonian systems Holonomic constraints symplecticity Quadratic invariants Partitioned Runge-Kutt methods

Dynamic mechanical characteristics of NdFeB in electromagnetic brake

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Defence Technology（防务技术） 2023年第1期19卷 111-125页

作者： Lei LI Guo-lai Yang li-qun Wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina

With the continuous development of artillery,the disadvantages of hydraulic recoil brakes gradually appear.At the same time,the appearance of high-performance Nd Fe B permanent magnet makes it possible to apply electromagnetic braking technology to recoil mechanism.In this paper,prototype tests of a certain artillery were carried out to verify the feasibility of the electromagnetic brake(EMB)and obtain the electromagnetic braking force.Due to the brittleness of Nd Fe B,in order to eliminate the worry about the safety of EMB,SHPB experiments of Nd Fe B were carried out.Then,based on the assumption of uniform crack distribution,the law of crack propagation and damage accumulation was described theoretically,and the damage constitutive model suitable for brittle materials was proposed by combining the Zhu-Wang-Tang(ZWT)equation.Finally,the numerical simulation model of the artillery prototype was established and through calculation,the dynamic mechanical characteristics of Nd Fe B in the prototype were analyzed.The calculation results show that the strength of Nd Fe B can meet the requirements of the use in the working process.From the perspective of damage factor,the damage value of the permanent magnet on the far right is larger,and the damage value of the inner ring gradually decreases to the outer ring.

关键词： Electromagnetic brake Sintered NdFeB Damage constitutive Dynamic mechanical characteristics

Metal-based nanoparticles for cardiovascular disease diagnosis and therapy

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Particuology 2023年第1期72卷 94-111页

作者： Lei LI Yun Zeng Gang liu State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics Center for Molecular Imaging and Translational MedicineSchool of Public HealthXiamen UniversityXiamen 361102China Department of Pharmacy Xiamen Medical CollegeXiamen 361023China

Cardiovascular diseases (CVDs) are the most prominent cause of disability and mortality in the world. Although there have been a variety of therapeutic options for the management of CVDs, most of the traditional therapeutic strategies could not sufficiently stop or reduce the progression of these diseases and may result in some side effects. With the advance in nanotechnology, a number of metal-based nanoparticles have been developed and shown promising potentials in the treatment of CVDs. In this review, we provide a comprehensive review of researches on recent development of metal-based nanoparticles in diagnosis and therapy in CVDs as biomedical materials. We also discuss the challenges in the clinical translation and potential risks in their application of CVD therapy. Based on the ongoing research and applications, we can conclude metal-based nanoparticles are expected to become potential therapeutics for the treatment of CVDs. But their application is still in its infancy and much more efforts should be made to enforce a clinical breakthrough.

关键词： Metal-based nanoparticles Nanomedicine Cardiovascular diseases Diagnosis Therapy

Superfluid λ transition in charged AdS black holes

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Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 29-36页

作者： Ning-Chen Bai Lei LI Jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu 610065China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringYibin 643000China

We observe a superfluid λ transition in the P-V criticality of charged Ad S black holes,within a holographic extended thermodynamics that considers the variation of Newton’s constant G.We calculate the critical exponents and find that they coincide with those of a superfluid transition in liquid4He and the Bose-Einstein condensation of hard-sphere Bose gas.Moreover,the independence of entropy and thermodynamic volume in the holographic framework allows us to construct a well-defined Ruppeiner metric.The associated scalar curvature suggests that the black holes show similar microscopic interactions with the hard-sphere Bose gas,where the superfluid(condensed)phase is dominated by repulsive interactions,while the normal(gas)phase is dominated by attractive interactions.These findings might provide us with new insights into the quantum aspect of charged Ad S black holes.

关键词： black hole thermodynamics holography superfluid phase transition Ruppeiner geometry

Secondary Parkinson disease caused by breast cancer during pregnancy: A case report

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World Journal of Clinical Cases 2019年第23期7卷 4052-4056页

作者： Lei LI Department of Obstetrics and Gynecology Peking Union Medical College Hospital

BACKGROUND Paraneoplastic neurological syndrome manifesting as secondary Parkinson disease caused by breast cancer is extremely rare.CASE SUMMARY We report a 39-year-old primipara of 31 gestational weeks,who presented with worsening tremors,facial stiffness and speech disfluencies,and decreased limb strength.Thorough physical examinations and auxiliary tests suggested secondary Parkinson’s disease,but the pathogenesis was unknown.During the cesarean section at the 31 weeks plus 6 d,an exploration and liver biopsy revealed a metastatic,poorly differentiated adenocarcinoma.The positron emission tomography and immunohistochemical analysis confirmed a breast ductal carcinoma of stage IV.To our knowledge,only two reports have documented the association between the breast cancer and the Parkinson disease,and neither occurred in pregnant women.CONCLUSION Our case alerts the secondary Parkinson disease as the possible presentation of breast cancer,the most common malignancy during pregnancy.

关键词： Secondary Parkinson disease Breast neoplasms Pregnancy Case report

Dynamic stiffness characteristics of aero-engine elastic support structure and its effects on rotor systems:mechanism and numerical and experimental studies

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 221-236页

作者： Lei LI Zhong LUO Kaining liU Jilai ZHOU School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern UniversityShenyang 110819China Foshan Graduate School of Innovation Northeastern UniversityFoshan 528312Guangdong ProvinceChina

The support structure of a rotor system is subject to vibration excitation,which results in the stiffness of the support structure varying with the excitation frequency(i.e.,the dynamic stiffness).However,the dynamic stiffness and its effect mechanism have been rarely incorporated in open studies of the rotor system.Therefore,this study theoretically reveals the effect mechanism of dynamic stiffness on the rotor system.Then,the numerical study and experimental verification are conducted on the dynamic stiffness characteristics of a squirrel cage,which is a common support structure for aero-engine.Moreover,the static stiffness experiment is also performed for comparison.Finally,a rotor system model considering the dynamic stiffness of the support structure is presented.The presented rotor model is used to validate the results of the theoretical analysis.The results illustrate that the dynamic stiffness reduces the critical speed of the rotor system and may lead to a new resonance.

关键词： dynamic stiffness squirrel cage rotor system dynamic characteristic critical speed

The multiple fronts of conquering cancer

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Science China(life Sciences) 2017年第10期60卷 1055-1057页

作者： Lei LI Department of Experimental Radiation Oncology The University of Texas MD Anderson Cancer Center Houston TX 77030 USA

Understanding and treating since tumors dawn have been a long journey when for mankind the of and the 1st century the Greek terms the'carcinoma''onco-'emerged not to the attempted document end recognition War of tumors.the It was until of World using II when first and chemotherapy succeeded was nitrogen mustard in curtailing the tumor burden and of a lymphoma 1946).patient(Gilman,types 1963;

关键词：抗癌症癌症治疗手术切除靶向治疗免疫疗法放射治疗肿瘤淋巴瘤