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Local-contrastive-learning machine with both generalization and adversarial robustness: A statistical physics analysis

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 109-123页

作者： Mingshan xie yuchen Wang Haiping Huang PMI Lab School of Physics Sun Yat-sen University Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Sun Yat-sen University

Distinct from human cognitive processing, deep neural networks trained by backpropagation can be easily fooled by adversarial examples. To design a semantically meaningful representation learning, we discard backpropagation, and instead, propose a local contrastive learning, where the representations for the inputs bearing the same label shrink(akin to boson) in hidden layers,while those of different labels repel(akin to fermion). This layer-wise learning is local in nature, being biologically plausible.A statistical mechanics analysis shows that the target fermion-pair-distance is a key parameter. Moreover, the application of this local contrastive learning to MNIsT benchmark dataset demonstrates that the adversarial vulnerability of standard perceptron can be greatly mitigated by tuning the target distance, i.e., controlling the geometric separation of prototype manifolds.

关键词： machine learning statistical mechanics adversarial robustness neural networks

FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： yuhui Kou Zongxue Jin yusong yuan Bo Ma Wenyong xie Na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina National Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen xie Liu Changqing Xu Da-Jian Wu ying Cheng Xiao-Jun Liu school of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPEs). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

study on the hydrogen absorption properties of a yGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang xie Wenjiao Zhou Huan Tong Dawen yang Anjia Zhang yuan Wu Xiping song state Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the yGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(Δs)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the yGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Deciphering deformation mechanisms of hierarchical dual-phase CrCoNi coatings

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Journal of Materials science & Technology 2020年第4期39卷 7-13页

作者： s.J.Tsianikas y.Chen Z.xie school of Mechanical Engineering The University of AdelaideAdelaideSA5005Australia Centre for Advanced Thin Film Materials and Device Faculty of Materials and EnergySouthwest UniversityChongqing400715China school of Engineering Edith Cowan UniversityWA6027Australia

Hierarchical Cr Co Ni medium entropy alloy(MEA)thin films with a dual-phase face-centred cubic(FCC)and hexagonal closed-packed(HCP)nanostructure were prepared on M2 steel substrates by closed field unbalanced magnetron *** tests show an ultra-high hardness of 9.5 GPa,attributable to large amounts of innate planar defects(i.e.,growth twins and stacking faults)impeding dislocation motion in the coatings.A deep analysis of undeformed and post-mortem samples reveals grain refinement as the dominant deformation mechanism in FCC dominated regions,while phase transformation and shear banding played major roles in regions occupied by HCP *** grain refinement was facilitated by twin/matrix lamellae,with dislocations piling up and arranging into interconnecting grain *** shear banding was accelerated by innate planar defects in the HCP phase due to a lack of slip *** particular interest is the observation of HCP→FCC phase transformation,which was catalysed by deformation-induced grain reorientation with innate stacking faults acting as embryos to grow the FCC *** results of this work suggest that multiple deformation pathways could be activated in Cr Co Ni coatings with assistance of growth defects,thereby imparting these technically important coatings appreciable ductility.

关键词： Medium entropy alloys sputter deposition Grain refinement shear banding Phase transformation

single-cell transcriptomic profiling reveals ZEB1-mediated regulation in microglial subtypes and the impact of exercise on neuroinflammatory responses

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Traditional Medicine Research 2025年第2期10卷 55-64页

作者： Jin-Fang Wu yi-sheng Chen yu-Chun xie Department of Rehabilitation Medicine Jiangsu Province Geriatric HospitalNanjing 210024China Fujian Key Laboratory of Toxicant and Drug Toxicology Medical CollegeNingde Normal UniversityNingde 352100China Central Laboratory Jiangsu Province Geriatric HospitalNanjing 210024China

Background:This study aims to identify distinct cellular subtypes within brain tissue using single-cell transcriptomic analysis,focusing on specific biomarkers that differentiate cell types and the effects of traditional and exercise ***:Four samples were analyzed:older control(OC),older exercise(OE),younger control(yC),and younger exercise(yE).single-cell RNA sequencing was used to distinguish cellular subtypes through their biomarker *** visualization included violin and t-sNE plots to illustrate biomarker expression across cell clusters such as oligodendrocytes,microglia,and ***,BV2 cells were exposed to amyloid-beta fragments to simulate Alzheimer’s disease,assessing the impact of exercise-induced cellular ***:Distinct cellular subtypes were identified:oligodendrocytes(MBP,st18),microglia(Dock8),and astrocytes(Aqp4,Gpc5).sample OE was predominantly oligodendrocytes,while yE had more astrocytes,inhibitory neurons,and Canal-Retzius *** showed a significant presence of Olfm3+ganglion ***1 gene knockout revealed changes in sMAD family gene expression,which regulate *** stress levels were also ***:This profiling enhances our understanding of brain cellular functions and interactions,potentially informing targeted therapies in neurological *** may influence brain cell immune responses and cell death pathways by regulating specific gene expressions,offering new insights for treating neuroinflammation and degeneration.

关键词： single-cell transcriptomics brain tissue cellular subtypes biomarker expression neuronal diversity

DsC AND TEM sTUDy OF ULTRA HIGH sTRENGTH ALUMINUM ALLOy

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Acta Metallurgica sinica(English Letters) 2004年第4期17卷 554-559页

作者： G.s.xie y.Zeng H.Ding Hunan Electric Power Test & Research Institute Changsha 410007 ChinaMaterial Department Central South University Changsha 410083 ChinaMaterial Department Wuhan University Wuhan 430072 China

In this paper, the effect of RRA treatment on the microstructure evolution of a high strength aluminum alloy was investigated using DsC, TEM and sADP technology. The results show that the precipitation resulting from RRA is extremely fine and distributed homogeneously in the grains, being slightly coarser and more stable than that of T6 temper. While, the grain-boundary precipitation is very close to that of the alloy at T73 temper, being coarse and discontinuous. High retrogression temperature and long retrogression time leads to a more stable microstructure after re-aging.

关键词： DsC TEM RRA Al-Zn-Mg-Cu alloy

Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin xie yuanhui Guo yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma Xin Chen Chingping Wong state Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China school of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China school of Materials science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode self-powered sensor

Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke xie Meng XIA Huarong CHENG Anyu LIU yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency