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Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： yifan Miao Li Zhao yajun Zhang Zhe yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

Influence of the velocity barrier on the massive Dirac electron transport in a monolayer MoS2 quantum structure

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Frontiers of physics 2020年第3期15卷 113-121页

作者： X.-J.Hao R.-y.yuan J.-J.Jin y.Guo Center for Theoretical Physics Department of PhysicsCapital Normal UniversityBeijing100048China Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing100084China Collaborative Innovation Center of Quantum Matter BeijingChina

Using the transfer matrix method,spin-and valley-dependent electron transport properties modulated by the velocity barrier were studied in the normal/ferromagnetic/normal monolayer MoS2 quantum *** on Snell’s Law in optics,we define the velocity barrier asξ=v2/v1 by changing the Fermi velocity of the intermediate ferromagnetic region to obtain a deflection condition during the electron transport process in the *** results show that both the magnitude and the direction of spin-and valley-dependent electron polarization can be regulated by the velocity barrier.−100%polarization of spin-and valley-dependent electron can be achieved forξ>1,while 100%polarization can be obtained forξy transport always occur at a large incident *** addition,the spin-and valley-dependent electron transport considerably depends on the length kFL and the gate voltage U(x)of the intermediate ferromagnetic *** findings provide an effective method for designing novel spin and valley electronic devices.

关键词： velocity barrier monolayer MoS2 spin valley polarization

Corrosion protection of NiNb metallic glass coatings for 316SS by magnetron sputtering

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Journal of Materials Science & Technology 2021年第20期79卷 88-98页

作者： L.Jiang Z.Q.Chen H.B.Lu H.B.Ke y.yuan y.M.Dong X.K.Meng School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China Institute of Materials Engineering National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210009China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China Institute of Materials Engineering Nanjing UniversityNantong 226019China College of Chemistry and Chemical Engineering Nantong UniversityNantong 226019China

Metallic glasses(MGs)appear as promising anti-corrosion coating materials due to their microstructural and physicochemical ***,we proposed magnetron sputtered NiNb thin film MG coatings(MGCs)with different structures and compositions for corrosion protection of 316 stainless steel in an aggressive saline *** properties of monolayered Ni_(50)Nb_(50) and Ni_(60)Nb_(40),as well as the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40)(at.%)MGCs,were characterized in terms of morphology and microstructural properties,as well as the anticorrosion *** the NiNb MGCs presented compact structure and the monolayered coatings exhibited preferable adhesion properties in comparison with the multilayered *** electrochemical tests and XPS results imply that the monolayered Ni_(50)Nb_(50) MGC with high Nb content resisted corrosion mainly due to the formation of stable passive film that contained abundant Nb_(2)O_(5) species,whereas the Ni_(60)Nb_(40) MGC with high Ni content showed week corrosion protection performance during long-term service due to the dissolution of Ni cations and the devastation of the coating *** with bit worse adhesion and more vulnerable Ni_(60)Nb_(40) layers,the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40) MGC possessed comparable corrosion resistance with the monolayered Ni_(50)Nb_(50) MG coating,which remained stable even after 32 days of *** performance should be ascribed to the combined eff;ect of the repassivation property for the sub-layers,the hindrance of propagation paths of micro-defects,and the obstruction of corrosive species by interfaces in the multilayered coating.

关键词： Magnetron sputtering NiNb Metallic glasses Multilayer Corrosion protection

Origin of Symmetry Breaking and Confinement in Conducting Polymers with Ring Structures

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Communications in Theoretical Physics 2007年第2X期48卷 366-368页

作者： yuan yuan Thomas F. george SUN Xin Research Center for Quantum Manipulation Fudan University Shanghai 200433 China National Lab of Infrared Physics Shanghai 200083 China Office of the Chancellor and Center for Molecular Electronics Departments of Chemistry & Biochemistry and Physics & Astronomy Univ.ersity of Missouri-St. Louis St. Louis Missouri 63121 USA

A model to describe the main features of conjugated polymers with ring structures, such as polythiophene and polypyrrole, is constructed. It is shown that the origin of the symmetry breaking and confinement of a solit... 详细信息

关键词： polymer branch hopping symmetry breaking confinement

小世界、结构洞与城市创新的网络机制:来自长三角城市群的证据

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管理工程学报 2025年第2期39卷 14-26页

作者：袁燕吴妍杨大鹏浙江科技大学经济与管理学院浙江金融职业学院电子商务与新消费研究院中共浙江省委党校工商管理教研部

近年来,创新网络作为区域和城市创新驱动力的重要性得到了广泛关注。一些研究将网络关系视为知识在城市内和城市间传播的渠道,并通过网络分析视角洞察城市创新的结构和动态。然而,城市创新的网络机制,特别是数字经济发展背景下的数字赋... 详细信息

近年来,创新网络作为区域和城市创新驱动力的重要性得到了广泛关注。一些研究将网络关系视为知识在城市内和城市间传播的渠道,并通过网络分析视角洞察城市创新的结构和动态。然而,城市创新的网络机制,特别是数字经济发展背景下的数字赋能城市创新能力提升机制还有待进一步研究。本文利用长三角城市群26个城市2009年—2018年联合申请专利数据构建了城市创新网络,探讨了网络结构属性——小世界和结构洞对城市创新能力的影响。结果表明,小世界与城市创新能力呈“倒U型”关系,数字经济发展水平正向调节了二者之间的“倒U型”关系,结构洞对城市创新能力具有正向影响。本文厘清了创新网络结构对城市创新能力的影响,回应了以往研究关于小世界和结构洞对创新影响的理论争议,为区域创新的理论研究提供了新颖性观点,深化了对城市群创新发展规律的认识,对推进中国城市群协同创新具有重要意义。

关键词：创新网络城市创新能力专利合作数字经济

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Asymptotic Properties of a Modified Semi-Parametric MLE in Linear Regression with Right-Censored Data

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Acta Mathematica Sinica,English Series 2002年第2期18卷 405-416页

作者： WONG george y.C. Strang Cancer Prevention Center.428 E 72nd Street.New york.Ny 10021.USA

Consider a linear regression model y=β'X+*** y may be right censored and the cdf F+o of e is *** show that a modified semi-parametric *** by .is strongly consistent under certain regularity *** F_o is discontinuous,then P(≠βi.o.)=0, which means that P(=βif the sample size is large)=*** latter property has not been reported for the existing *** contrast,most estimators,such as the Buckley-James estimator and M-estimators .satisfy that P(≠βi.o.)=1.

关键词： Consistency Super-efficiency Semi-parametric MLE

Mathematical modelling of axonal microtubule bundles under dynamic torsion

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Applied Mathematics and Mechanics(English Edition) 2018年第6期39卷 829-844页

作者： J.y.WU Hong yuan L.y.LI MOE Key Laboratory of Disaster Forecast and Control in Engineering Institute of Applied MechanicsJinan University School of Engineering University of Plymouth

Owing to its viscoelastic nature, axon exhibits a stress rate-dependent me- chanical behavior. An extended tension-shear chain model with Kelvin-Voigt viscoelas- ticity is developed to illustrate the micromechanical behavior of the axon under dynamic torsional conditions. Theoretical closed-form expressions are derived to predict the de- formation, stress transfer, and failure mechanism between microtubule （MT） and tau protein while the axon is sheared dynamically. The results obtained from the present an- alytical solutions demonstrate how the MT-tau interface length, spacing between the tau proteins, and loading rate affect the mechanical properties of axon. Moreover, it is found that the MTs are more prone to rupture due to the contributions from the viscoelastic effects. Under the torsional force, the MTs are so long that the stress concentrates at the loaded end where axonal MTs will break. This MT-tau protein dynamics model can help to understand the underlying pathology and molecular mechanisms of axonal injury. Additionally, the emphasis of this paper is on the micromechanical behavior of axon, whereas this theoretical model can be equally applicable to other soft or hard tissues, owning the similar fibrous structure.

关键词： torsion biocomposite diffuse axonal injury (DAI) Kelvin-Voigt viscoelas-tic model dynamic response tension-shear chain model

Pathogenesis of Thrombocytopenia in Chronic HCV Infection:A Review

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Journal of Clinical and Translational Hepatology 2020年第2期8卷 184-191页

作者： Sarah Rawi george y Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

A large proportion of patients with chronic hepatitis C have associated thrombocytopenia (TCP). Due to bleeding risks, TCP, when severe, can limit diagnostic and therapeutic procedures, treatments, and increases risk of complications, especially excessive bleeding. It is important to understand the mechanisms that cause TCP in order to manage it. In general, TCP can be due to increased destruction or decreased production. Proposed mechanisms of increased destruction include autoantibodies to platelets and hyper-splenism with sequestration. Proposed mechanisms of de-creased production include virus-induced bone marrow suppression and decreased TPO production. Autoantibodies directed against platelet surface antigens have demonstrated an inverse correlation with platelet counts. Hypersplenism with sequestration involves the interaction of portal hyper-tension, splenomegaly, and platelet destruction. Decreased production mechanisms involve appropriate and inappropri-ate levels of TPO secretion. There is limited evidence to support viral-induced bone marrow suppression. In contrast, there is strong evidence to support low levels of TPO in liver failure as a major cause of TCP. TPO-agonists, specifically eltrombopag, have been shown in hepatitis C patients to increase platelet counts without reducing portal hypertension or splenomegaly. We conclude that TCP in hepatitis C virus-induced liver disease is often multifactorial, but an under-standing of the mechanisms can lead to judicious use of new drugs for treatment.

关键词： Thrombocytopenia Chronic hepatitis Autoantibodies Hypersplenism Thrombopoietin

Crystal Structure of Arabidopsis thaliana Dawdle Forkhead-Associated Domain Reveals a Conserved Phospho-Threonine Recognition Cleft for Dicer-Like 1 Binding

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Molecular Plant 2013年第4期6卷 1290-1300页

作者： Satoru Machida y.Adam yuan Department of Biological Sciences and Centre for Bioimaging Sciences National University of Singapore 14 Science Drive 4 Singapore 117543 Singapore Temasek Lifesciences Laboratory National University of Singapore 1 Research Link Singapore 117604 Singapore Mechanobiology Institute National University of Singapore T-lab Building 5A Engineering Drive 1 Singapore 117411 Singapore

Dawdle （DDL） is a microRNA processing protein essential for the development of Arabidopsis. DDL contains a putative nuclear localization signal at its amino-terminus and forkhead-associated （FHA） domain at the carboxyl-termi- nus. Here, we report the crystal structure of the FHA domain of Arabidopsis Dawdle, determined by multiple-wavelength anomalous dispersion method at 1.7-A resolution. DDL FHA structure displays a seven-stranded 13-sandwich architec- ture that contains a unique structural motif comprising two long anti-parallel strands. Strikingly, crystal packing of the DDL FHA domain reveals that a glutamate residue from the symmetry-related DDL FHA domain, a structural mimic of the phospho-threonine, is specifically recognized by the structurally conserved phospho-threonine binding cleft. Consistently with the structural observations, co-immuno-precipitation experiments performed in Nicotiana benthami- ana show that the DDL FHA domain co-immuno-precipitates with DCL1 fragments containing the predicted pThr＋3（lle/ Val/Leu/Asp） motif. Taken together, we count the recognition of the target residue by the canonical binding cleft of the DDL FHA domain as the key molecular event to instate FHA domain-mediated protein-protein interaction in plant miRNA processing.

关键词： Arabidopsis DCL1 Arabidopsis DDL forkhead-associated domain phospho-threonine microRNA processing.