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On Klein tunneling of low-frequency elastic waves in hexagonal topological plates

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1139-1154页

作者： Yuxin YAO Yuansheng MA fang HONG Kai ZHANG Tingting WANG haijun PENG Zichen DENG School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical University State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

Incident particles in the Klein tunnel phenomenon in quantum mechanics can pass a very high potential barrier. Introducing the concept of tunneling into the analysis of phononic crystals can broaden the application prospects. In this study, the structure of the unit cell is designed, and the low frequency(< 1 k Hz) valley locked waveguide is realized through the creation of a phononic crystal plate with a topological phase transition interface. The defect immunity of the topological waveguide is verified,that is, the wave can propagate along the original path in the cases of impurities and disorder. Then, the tunneling phenomenon is introduced into the topological valley-locked waveguide to analyze the wave propagation, and its potential applications(such as signal separators and logic gates) are further explored by designing phononic crystal plates. This research has broad application prospects in information processing and vibration control,and potential applications in other directions are also worth exploring.

关键词： topological metamaterial elastic wave Klein tunneling valley-locked waveguide O347.4 + 1 74J05

Design of switched linear systems in the presence of actuator saturation and L-infinity disturbances

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控制理论与应用（英文版） 2010年第3期8卷 333-343页

作者： Liang LU Zongli LIN haijun fang Department of Automation Shanghai/iao Tong University Shanghai 200030 China Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 Charlottesville VA 22904-4743 USA MKS Instrument 100 Highpower Road Rochester NY 14623 USA

This paper considers the problem of disturbance tolerance/rejection of a switched system resulting from a family of linear systems subject to actuator saturation and E-infinity disturbances. For a given set of linear feedback gains, a given switching scheme and a given bound on the E-infinity norm of the disturbances, conditions are established, in terms of linear or bilinear matrix inequalities, under which a set of a certain form is invariant for a given switched linear system in the presence of actuator saturation and E-infinity disturbances, and the closed-loop system possesses a certain level of disturbance rejection capability. With these conditions, the design of feedback gains and switching scheme can be formulated and solved as constrained optimization problems. Disturbance tolerance is measured by the largest bound on the disturbances for which the trajectories starting from a given set remain bounded. Disturbance rejection is measured either by the E-infinity norm of the system output or by the system＇s ability to steer its state into and/or keep it within a small neighborhood of the origin. In the event that all systems in the family are identical, the switched system reduces to a single system under a switching feedback law. Simulation results show that such a single system under a switching feedback law could have stronger disturbance tolerance/rejection capability than a single linear feedback law can.

关键词： Actuator saturation Disturbance rejection Disturbance tolerance L-infinity performance Set invariance Switched systems

Effect on serum metabolomics of rats with premature ovarian insufficiency by Zhibian(BL54) through Shuidao(ST28) acupuncture

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Journal of Traditional Chinese Medicine 2024年第4期44卷 722-733页

作者： YAN Jing FENG Huimin QIU fang WANG haijun YIN Luyun JIN Xiaofei ZHAO Jiyu WANG Hongyang YAN Xiaoqin Second Clinical College of Shanxi University of Traditional Chinese Medicine Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese Medicine Department of Cervical and Lumbar Vertebral Diseases Jinzhong Hospital Affiliated to Shanxi University of Traditional Chinese Medicine

OBJECTIVE: To analyze the serum metabolic targets of the "Zhibian(BL54) through Shuidao(ST28)" acupuncture technique in cyclophosphamide(CTX)-induced premature ovarian insufficiency(POI) model rats and to elucidate the potential molecular mechanism of acupuncture in improving POI. METHODS: We used an intraperitoneal injection of CTX to establish the POI rat model(POI group) and compared serum hormone levels and ovarian histopathological changes to evaluate the effect of the Zhibian(BL54) through Shuidao(ST28) technique(ZS + POI group) on ovarian function. Then, nontargeted metabolomics was performed using rat serum by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF/MS). RESULTS: After acupuncture intervention, the serum hormone levels and ovarian pathological morphology of POI rats were effectively improved. Moreover, UPLC-Q-TOF/MS results showed that the ZS+POI group showed a significant reversal of the levels of 6 differential metabolites. Among them, the levels of four serum metabolic markers, divanillyltetrahydrofuran ferulate, trans-ferulic acid, tryptamine, and neuraminic acid, increased significantly. Further analysis of biological effects showed that all metabolites were involved in the regulation of reproductive hormone levels and antioxidant and antiapoptotic effects. CONCLUSIONS: The "Zhibian(BL54) through Shuidao(ST28)" acupuncture method may improve the ovarian function of POI rats by regulating serum metabolite markers to exert antioxidant and antiapoptotic effects, which provides a theoretical basis for the clinical application of acupuncture in the treatment of POI.

关键词： Zhibian (BL54) through Shuidao (ST28) acupuncture metabolomics premature ovarian insufficiency ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry

Blood circulation activating effect of Sanqi(Radix Notoginseng) on venous thromboembolism rats

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Journal of Traditional Chinese Medicine 2021年第5期41卷 753-761页

作者： ZHU Chen JIANG Huifang ZHOU Xiaqing ZHANG Zhirong WU Yu fang haijun WANG Lingcong Department ICU of the First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006China Department of Hematology Tongde Hospital of Zhejiang ProvinceHangzhou 310012China Department Orthopaedics of the First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006China Department Dental of the First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006China

OBJECTIVE:To explore the blood circulation activating effect and mechanism of Sanqi(Radix Notoginseng)in vivo,using a venous thromboembolism(VTE)rat ***:We established the VTE rat model,and then intervened with low molecular weight hepa-rin(LMWH),as well as low,medium and high doses of Sanqi(Radix Notoginseng),to observe the blood circulation activating effect of Sanqi(Radix Notoginseng)on VTE ***:After the treatment with high concentrations of Sanqi(Radix Notoginseng),the pulmonary thromboembolism was alleviated,and the lower limb thrombosis was markedly ***,the expression quantities of plasma activated partial thromboplastin time,prothrombin time and D-dimer,as well as endothelin,von Willebrand factor,and plasminogen activator inhibitor-1 in thrombosis segment tissues were markedly down-regulated;while those of nitric oxide and tissue-type plasminogen activator were *** low and medium concentration Sanqi(Radix Notoginseng)treatment,no obvious improvement was observed in each ***,the high concentration Sanqi(Radix Notoginseng)showed comparable efficacy to the positive drug ***:This data suggests that high concentration of Sanqi(Radix Notoginseng)is effective in preventing and treating VTE.

关键词： venous thromboembolism blood circulation heparin,low-molecular-weight Sanqi(Radix Notoginseng)

Probing the Galactic Halo with RR Lyrae Stars. VI. The Radial Velocity Curve Templates of RRc Stars

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Research in Astronomy and Astrophysics 2024年第7期24卷 121-137页

作者： Yue Huang Min fang Gaochao Liu Xianzhong Zheng Sarah Ann Bird Yang Huang Jianrong Shi Jiangtao Wang Huawei Zhang haijun Tian Haotong Zhang College of Science China Three Gorges University Center for Astronomy and Space Sciences China Three Gorges University Purple Mountain Observatory Chinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China School of Astronomy and Space Science University of Chinese Academy of Sciences CAS Key Laboratory of Optical Astronomy National Astronomical Observatories Department of Astronomy School of PhysicsPeking University Kavli Institute for Astronomy and Astrophysics Peking University School of Sciences Hangzhou Dianzi University

We present radial velocity（RV） curve templates of RR Lyrae first-overtone（RRc） stars constructed with the Mg I b triplet and Hα lines using time-domain Medium-Resolution Survey spectra of seven RRc stars from Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST） Data Release 9. Additionally, we derive the relation between the stellar RV curve amplitudes and g-band light curve amplitudes from Zwicky Transient Facility（ZTF）public survey. For those RRc stars without ZTF g-band light curves, we provide the conversions from the light curve amplitudes in ZTF r-and i-bands, Gaia G-band, and V-band from the All-Sky Automated Survey for Supernovae to those in ZTF g-band. We validate our RV curve templates using the RRc star SV Scl and find the uncertainties of systemic RV are less than 2.11 km s-1and 6.08 km s-1based on the Mg I b triplet and Hα lines,respectively. We calculate the systemic RVs of 30 RRc stars using the RV curve templates constructed with the Mg I b triplet and Hα lines and find the systemic RVs are comparable with each other. This RV curve template will be particularly useful for obtaining the systemic RV of RRc using the LAMOST spectroscopy.

关键词： Stars stars: variables: RR Lyrae techniques: radial velocities

Ultratough Yet Dynamic Crystalline Poly(thiourethane)Network Directly from Low Viscosity Precursors

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CCS Chemistry 2024年第3期6卷 682-692页

作者： haijun Feng Yi Sheng Guancong Chen Binjie Jin Zizheng fang Bo Yang Xiaorui Zhou Wenxuan Wu Tao Xie Ning Zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310058 Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310027

Thermosets based on direct curing of multifunctional monomers offer processing flexibility that thermoplastics cannot ***,this type of thermoset is typically amorphous since it is difficult to meet the stringent requirement of long-range molecular regularity for ***,we report here a crystallizable poly(thiourethane)thermoset synthesized directly from the curing of low-viscosity liquid precursors that does not employ any *** crystalline nature results in superior toughness,comparable to commercial high-density polyethylene,in sharp contrast to the brittleness of the typical,rigid,glassy thermoset *** that,the network polymer exhibits shape-memory behavior in which the crystalline transition is utilized for temporary shape fixing/recovery whereas the dynamic thiourethane bonds can be activated for bond exchange as a mechanism for complex shape *** with these combined features represent attractive options for demanding engineering applications due to their high performance and multifunctinality.

关键词： thermosets crystalline polymer thiourethane thermadapt

Efficacy of Sanqi(Radix Notoginseng)in treating cerebral hemorrhage in rats with traumatic brain injury

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Journal of Traditional Chinese Medicine 2021年第2期41卷 262-269页

作者： JIANG Tao ZHOU Xiaqing JIANG Huifang YING Rongbiao ZHANG Zhirong CAI Danli WU Yu fang haijun WANG Lingcong Department of Neurosurgery of the First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006China Department of Intensive Care Unit of the First Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310006China Department of Hematology Tongde Hospital of Zhejiang ProvinceHangzhou 310012China Department of Surgical Oncology Tumor Hospital of TaizhouWenling 317502China

OBJECTIVE:To evaluate the protective efficacy of Sanqi(Radix Notoginseng)on cerebral hemorrhage in a rat model of traumatic brain injury(TBI)by investigating plasminogen activator inhibitor-1(PAI-1),tissue-type plasminogen activator(t-PA),nuclear factor-κB(NF-κB,p-p65),nitric oxide(NO),endothelin(ET),cluster differentiation(CD61CD62),and ***:The free-fall method was used to create a rat model of ***-eight rats were randomly divided into six groups:the blank group,sham group,model group,low-dose Sanqi(Radix Notoginseng)group,middle-dose Sanqi(Radix Notoginseng)group,and high-dose Sanqi(Radix Notoginseng)*** 24 h after the model was created,we investigated brain MRI,brain tissue morphology using HE staining,flow cytometry,and immunohistochemical ***:Cerebral hemorrhage was aggravated in TBI rats(observed in brain specimens,brain MRI,and brain tissue HE).Cerebral immunohistochemistry results demonstrated that the expression of t-PA,PAI-1 and p-p65 increased significantly in TBI rats,while t-PA/PAI-1 had a significant *** addition,CD61CD62,D2D,and ET were significantly increased in TBI rats,and PT and APTT were significantly prolonged;in contrast,NO was significantly ***(Radix Notoginseng)decreased cerebral hemorrhage in TBI rats(observed in brain MRI and brain tissue HE),and increased t-PA/PAI-1,CD61CD62 *** also significantly decreased the expression of t-PA,PAI-1,and p-p65 in brain immunohistochemistry and significantly decreased PT,APTT,D2D,and ***,there were no differences in NO between the model group and the Sanqi(Radix Notoginseng)***:Sanqi(Radix Notoginseng)can decrease the expression of p-p65,increase t-PA/PAI-1,and stem traumatic intracranial hemorrhage in a TBI rat model.

关键词： Sanqi(Radix Notoginseng) Brain injuries,traumatic Plasminogen activator inhibitor-1 Tissue-type plasminogen activator p-p65

社会保险费强制征缴的现实之需、实施困境及其应对

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北京理工大学学报（社会科学版） 2019年第3期21卷 166-173页

作者：房海军武汉大学法学院湖北武汉430072

社会保险费的强制征缴既是社会保险强制性的体现,也是保费征收主体履行法定职责,维护社保基金安全的机制保障,更是实现社保征缴规范化,保障参保人社保权利的应然要求。中国当前社保费率过高、普遍化的低基数缴费、职工参保动力不足以及... 详细信息

社会保险费的强制征缴既是社会保险强制性的体现,也是保费征收主体履行法定职责,维护社保基金安全的机制保障,更是实现社保征缴规范化,保障参保人社保权利的应然要求。中国当前社保费率过高、普遍化的低基数缴费、职工参保动力不足以及保费补缴困难是落实社保费强制征缴机制的主要困境。困境之源在于社保制度设计存在以下问题:社保转制以及扩面中政府财政责任缺位、费基的变相调整导致社保基数难以做实、缴费与待遇关联性弱降低了参保群体社保遵从度以及社保补缴实体内容立法缺失。透过政府财政责任归位降低社保费率、缴费基数的法定化、权利义务相一致的制度激励机制构建以及保费补缴主体与补缴时效的法律明确,可实现困境突破,最终确保社保费强制征缴机制的落实。

关键词：社会保险费强制征缴社保费率缴费基数社保补缴

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稀溶液中大幅拉伸高分子单链的弛豫动力学

高等学校化学学报 2024年第4期45卷 134-141页

作者：姚宁王海军李江涛顾芳廖琦河北大学化学与材料科学学院保定071002 河北大学河北省化学生物学重点实验室保定071002 河北大学药物化学与分子诊断教育部重点实验室保定071002 中国科学院北京化学研究所北京100190

针对大幅拉伸的高分子单链在Θ溶剂和良溶剂中的弛豫过程,分别通过解析理论和分子动力学模拟方法研究了弛豫动力学.对比研究发现,相对于研究高分子链在平衡态下的弛豫动力学(利用有关物理量的自关联函数),本文的非平衡态方法可以明确地... 详细信息

针对大幅拉伸的高分子单链在Θ溶剂和良溶剂中的弛豫过程,分别通过解析理论和分子动力学模拟方法研究了弛豫动力学.对比研究发现,相对于研究高分子链在平衡态下的弛豫动力学(利用有关物理量的自关联函数),本文的非平衡态方法可以明确地揭示弛豫时间与简正模式之间标度行为的动态演化.结果表明,相关的物理量在弛豫初期均受到非平衡态的影响,而在较长时间后,高分子链的弛豫动力学则与平衡态下的结果相吻合;在高分子链的最长弛豫时间与链长的标度关系方面,平衡态和非平衡态两种方法的研究结果也一致.研究结果表明,高分子链在非平衡态下的短时和长时弛豫动力学可以更加细致地阐明弛豫全过程,给出更加丰富的结构-特征关系,从而为深入探讨高分子链的非平衡弛豫提供可借鉴的线索.

关键词：高分子单链弛豫动力学简正模式弛豫时间