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Quantum electrodynamics experiments with colliding petawatt laser pulses

High power Laser Science and Engineering 2019年第1期7卷 74-81页

作者： I. C. E. turcu B. Shen D. Neely G. Sarri K. A. tanaka p. McKenna S. p. D. Mangles t.-p. yu W. Luo X.-L. Zhu Y. Yin StFC Rutherford Appleton Laboratory Central Laser Facility School of Electronic Science and Engineering Nanjing University ELI-Np Extreme Light Infrastructure – Nuclear physics National Institute of Physics and Nuclear Engineering (IFIN HH) State Key Laboratory of High Field Laser physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences School of physical Science and technology ShanghaiTech University Shanghai Normal University School of Mathematics and physics Queen’s University Belfast SUpA Department of physics University of Strathclyde the John Adams Institute for Accelerator Science Imperial College London Department of physics National University of Defense Technology School of Nuclear Science and technology University of South China Key Laboratory for Laser plasmas (MOE) School of Physics and Astronomy Shanghai Jiao Tong University

A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt(pW)and even 100 pW, capable of reaching intensities of 1023 W/cm^2 in the laser focus. these ultra-high intensities are nevertheless lower than the Schwinger intensity IS= 2.3×1029 W/cm^2 at which the theory of quantum electrodynamics(QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. to enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding pW laser pulses is being adopted. theoretical simulations predict strong QED effects with colliding laser pulses of 10 pW focused to intensities 10^(22) W/cm^2.

关键词： colliding petawatt laser pulses electron-positron pairs creation nonlinear Breit-Wheeler process petawatt laser facilities quantum electrodynamics

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Betatron-like resonance in ultra-intense laser mass-limited foil interaction

Betatron-like resonance in ultra-intense laser mass-limited ...

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第七届全国青年计算物理学术会议

作者： t p yu Z M Sheng A pukhov Y Yin H B Zhuo Y Y Ma X H Xu F Q Shao C t Zhou College of Science National University of Defense Technology State Key Laboratory of High performance Computing National University of Defense Technology Key Laboratory for Laser plasmas (MoE) and Department of physics Shanghai Jiao Tong University Institut fr theoretische physik I Heinrich-Heine-Universitt Düsseldorf Institute of Applied physics and Computational Mathematics

With the help of three-dimensional particle-in-cell simulations, we study the electron dynamics in radiation pressure acceleration of a mass-limited foil target. When a mass-limited foil is irradiated by a circularly polarized laser pulse, the wing parts of the laser overtake the foil from the foil boundaries. In the laser propagation direction, electrons are significantly accelerated by the laser radiation pressure. In the laser polarization direction, electrons are subjected to a strong radial space-charge force and oscillate in the overtaking laser *** their combined actions, electrons execute a betatron-like oscillation and a spatially helix electron bunch is thus formed. A simple analytical model is proposed for interpreting the high electron energies and large oscillating amplitudes. It is shown that, when the electron oscillation frequency coincides with the laser frequency as witnessed by the electron,betatron-like resonance occurs, resulting in hundreds of MeV electron generation.

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Attention Eraser and Quantitative Measures for Automated Bone Age Assessment

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Computers, Materials & Continua 2025年第1期82卷 627-644页

作者： Liuqiang Shu Lei yu College of Computer and Information Science Chongqing Normal UniversityChongqing401331China

Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological *** predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for *** this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained ***,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent *** is trained and validated on the RSNA,RHpE,and digital hand atlas datasets,which include images from various racial *** model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHpE *** to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(pth a reduction in MAE by 0.2±0.02 years across different racial ***,t-tests on the features also confirm the statistical significance of our approach(p<0.05).

关键词： Bone age assessment attention eraser quantitative feature metacarpal bones

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tilting homeostatic and dyshomeostatic microglial balance in health and disease:transforming growth factor-beta1 as a critical protagonist

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Neural Regeneration Research 2025年第10期20卷 2895-2897页

作者： Nicolas Hugues yu Luo Department of Molecular and Cellular Biosciences University of CincinnatiCincinnatiOHUSA Neuroscience Graduate program University of CincinnatiCincinnatiOHUSA Division of Immunobiology Cincinnati Children’s Hospital Medical CenterUniversity of Cincinnati College of MedicineCincinnatiOHUSA

Adult microglia,by continuously sensing changes in their environment and communicating with nearly all brain cell types,are considered to be the immune sentinels of the *** the healthy central nervous system(CNS),microglia display a unique molecular homeostatic signature(i.e.,tmem119,p2ry12,Sall1,Siglech,Gpr34,and Hexb)(Figure 1A).

关键词： Figure signature critical

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targeting trkB–pSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang yu-Wen Alvin Huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

tropomyosin receptor kinase B(trkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic trkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with trkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss trkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of trkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with trkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated trkB.t1 *** trkB agonists and antibodies that activate trkB are being intensively investigated,they cannot distinguish the multiple human trkB splicing isoforms or cell type-specific *** trkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost trkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity trkB

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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2p for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin peng yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2p by concurrently introducing B-doped atoms and p vacancies in Ni2p （Vp-B-Ni2p）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and p vacancies in Ni2p causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LipSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and p vacancies in Ni2p selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2p-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

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Integration of Electrical properties and polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang yuefeng Yan Zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang yu Zhou State Key Laboratory of precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIt Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

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Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao Zhang Zhanyu Li Yijia Lei Baozeng Sun Xiaoyu yu Zhe Wang College of Chemistry and Life Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional polymer Membrane Materials of Jilin province

the development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that ptI-ptF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on ptI-ptF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： potassium hydroxide

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Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei yu Yongxian Huang Guoyan Chen Xiaoqing Yang Canyi Du Yongkang Gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

to accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENEt),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENEt model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-term Memory(LStM),transformer,and Multi-Scale Residual Networks(MSRESNEt),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENEt model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENEt model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LStM and transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LStM and SENEt models using t-distributed Stochastic Neighbor Embedding(t-SNE)*** findings revealed that,in the LStMmodel,data points of the same type tended to cluster together with significant ***,in the SENEt model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENEt model engine misfire fault fault detection

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Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao yu-Gui peng peng Wu Zong-Lin Li Xue-Feng Zhu School of physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

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