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Spin asymmetry and dipole moments inτ-pair production with ultraperipheral heavy ion collisions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 15-21页

作者： Dingyu Shao bin Yan Shu-Run Yuan Cheng Zhang Department of Physics Center for Field Theory and Particle PhysicsFudan UniversityShanghai 200433China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics National Natural Science Foundation of China(NSFC)and Fudan UniversityShanghai 200438China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics Peking UniversityBeijing 100871China

The anomalous magnetic(MDM)and electric(EDM)dipole moments of theτlepton serve as crucial indicators of new physics beyond the standard *** azimuthal angular asymmetry as a novel tool in ultraperipheral collisions(UPCs),we attain unparalleled precision in the study of these key *** by the highly linear polarization of coherent photons,this method uniquely enables both the MDM and EDM to contribute to the cos 2φangular distribution in similar ***,our approach substantially narrows the parameter space,excluding more than half of it compared to expected UPC-based measurements reliant solely on the total *** method not only provides improved constraints but also minimizes the need for additional theoretical assumptions,and offers a novel avenue to probe the EDM effects.

关键词： ultraperipheral collisions magnetic and electric dipole moments spin asymmetry

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Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions

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Plant Diversity 2024年第2期46卷 265-273页

作者： Ju Li Shu-bin Zhang Yang-Ping Li CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina University of Chinese Academy of Sciences Beijing 100049China

To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native ***,few studies have compared the photosynthetic dynamics between invasive and native species during light *** compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady *** photosynthetic dynamics and leaf traits differed among *** showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun ***,the slow induction response may be attributed to the longer stomatal length in *** had a significant effect on photosynthetic dynamics in *** and *** but not in *** shady habitat,*** had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in *** than in the two native *** contrast,*** had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic ***,in both habitats,*** had an overall higher carbon gain during light fluctuations than the two native *** results indicated that *** can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.

关键词： Invasive plant Photosynthetic induction Photosynthetic relaxation Carbon gain Stomatal traits Tithonia diversifolia

Security-Reliability Tradeoff Analysis for Jamming Aided Decode-and-Forward Relay Networks

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China Communications 2024年第5期21卷 218-228页

作者： Zou Ronggui Zou Yulong Zhu Jia Li bin School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

In this paper,we explore a cooperative decode-and-forward(DF)relay network comprised of a source,a relay,and a destination in the presence of an *** improve physical-layer security of the relay system,we propose a jamming aided decodeand-forward relay(JDFR)scheme combining the use of artificial noise and DF relaying which requires two stages to transmit a ***,in stage one,the source sends confidential message to the relay while the destination acts as a friendly jammer and transmits artificial noise to confound the *** stage two,the relay forwards its re-encoded message to the destination while the source emits artificial noise to confuse the *** addition,we analyze the security-reliability tradeoff(SRT)performance of the proposed JDFR scheme,where security and reliability are evaluated by deriving intercept probability(IP)and outage probability(OP),*** the purpose of comparison,SRT of the traditional decode-and-forward relay(TDFR)scheme is also *** results show that the SRT performance of the proposed JDFR scheme is better than that of the TDFR ***,it is shown that for the JDFR scheme,a better SRT performance can be obtained by the optimal power allocation(OPA)between the friendly jammer and user.

关键词： decode-and-forward relay friendly jammer physical layer security power allocation security-reliability tradeoff

Design of distributed dynamic absorbers for vibration suppression of panel structures

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Acta Mechanica Sinica 2024年第7期40卷 164-180页

作者： Liyuan Li bin Li Zehua Xu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China China Aero-Polytechnology Establishment Beijing 100028China

Distributed dynamic absorbers have many advantages such as wide frequency bandwidth for vibration suppression,strong detuning adaptability,and high system stability,making them very suitable for the vibration and noise control of continuous ***,they have broad application prospects in various fields such as transportation,aviation,and ***,there are still many challenges in the engineering applications of distributed dynamic absorbers for vibration suppression,including the engineering realization of the optimal damping of traditional optimal coherence dynamic absorbers,and the engineering applicability of the finite periodic array dynamic *** on the damping material properties obtained by the dynamic mechanical analyzer tests,this paper establishes the finite element model of the cantilever-beam-type dynamic absorber with constrained damping layers,aiming to realize the accurate determination of the optimal *** are conducted by attaching the traditional dynamic absorbers with the optimal damping to a thin-walled panel with four clamped *** show that the vibration of the panel is well suppressed,with the reduction of the frequency response peak larger than 14 dB and the reduction ratio of RMS larger than 58%within 500 ***,the periodically arrayed dynamic absorbers are designed according to the bandgap regulation *** tuning behavior of the arrayed dynamic absorbers by changing designing parameters is *** vibration reduction effect of arrayed dynamic absorbers is compared with that of the traditional dynamic absorbers under the same mass ratio through *** indicate that the arrayed dynamic absorbers are easier to design,and have a similar reduction effect on the modal vibration of the thin panel as the traditional dynamic absorbers within a narrow frequency range near the natural frequency,while they perform unsatisfactory in a broad ***,if t

关键词： Distributed dynamic absorbers Engineering realization of the optimal damping Vibration suppression Low-frequency and broadband

Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

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China Communications 2024年第6期21卷 23-39页

作者： Jiang Jie Lyu bin Chen Pengcheng Yang Zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

A method for extracting the preseismic gravity anomalies over the Tibetan Plateau based on the maximum shear strain using GRACE data

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Earth and Planetary Physics 2024年第4期8卷 589-608页

作者： Hui Wang DongMei Song XinJian Shan bin Wang College of Oceanography and Space Informatics China University of Petroleum(East China)Qingdao 266580China PCI Technology Group Co. Ltd.Guangzhou 510660China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266200China State Key Laboratory of Earthquake Dynamics Beijing 100029China

The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in *** Gravity Recovery And Climate Experiment(GRACE)satellite data can be used to detect gravity changes associated with large ***,previous GRACE satellite-based seismic gravity-change studies have focused more on coseismic gravity changes than on preseismic gravity ***,the noise of the north–south stripe in GRACE data is difficult to eliminate,thereby resulting in the loss of some gravity information related to tectonic *** explore the preseismic gravity anomalies in a more refined way,we first propose a method of characterizing gravity variation based on the maximum shear strain of gravity,inspired by the concept of crustal *** offset index method is then adopted to describe the gravity anomalies,and the spatial and temporal characteristics of gravity anomalies before earthquakes are analyzed at the scales of the fault zone and plate,*** this work,experiments are carried out on the Tibetan Plateau and its surrounding areas,and the following findings are obtained:First,from the observation scale of the fault zone,we detect the occurrence of large-area gravity anomalies near the epicenter,oftentimes about half a year before an earthquake,and these anomalies were distributed along the fault ***,from the observation scale of the plate,we find that when an earthquake occurred on the Tibetan Plateau,a large number of gravity anomalies also occurred at the boundary of the Tibetan Plateau and the Indian ***,the aforementioned experiments confirm that the proposed method can successfully capture the preseismic gravity anomalies of large earthquakes with a magnitude of less than 8,which suggests a new idea for the application of gravity satellite data to earthquake research.

关键词： Gravity Recovery And Climate Experiment(GRACE)data maximum shear strain offset index K preseismic gravity anomalies Tibetan Plateau fault zone

Resilience conferred by APOE-R136S:a defense bestowed by nature to combat Alzheimer’s disease

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Signal Transduction and Targeted Therapy 2024年第3期9卷 831-832页

作者： bin Xiao Joshua Kuruvilla Eng-King Tan Department of Neurology National Neuroscience InstituteSingaporeSingapore Neuroscience Academic Clinical Program Duke-NUS Medical SchoolSingaporeSingapore Neuroscience and Behavioural Disorders Program Duke-NUS Medical SchoolSingaporeSingapore

In two recent articles published in Nature Neuroscience and Cell,Nelson et al.1 and Chen et al.2 have shown that a rare APOE3 Christchurch(APOE3Ch)variant,R136S,has protective effects on neurodegeneration in various Alzheimer’s disease(AD)model systems through attenuating tau pathology and regulating its related neuroimmune *** et *** Chen et *** provided evidence that identifying the pathophysiologic clues and potential molecular targets from a protective variant such as APOE R136S,can be an attractive viable approach to develop AD therapeutics.

关键词： protective al. Alzheimer

Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter

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Research in Astronomy and Astrophysics 2024年第1期24卷 128-134页

作者： Hengjie Lin Yan Gong bin Yue Xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Science Center for China Space Station Telescope National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100871China

A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation ***,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR *** dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass *** provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization *** the other hand,the constraints on the properties of WDM can be derived from the JWST *** this work,we study WDM as a possible solution to reconcile the JWST stellar mass density of high-z massive galaxies and reionization *** find that,the JWST high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM *** using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWST high-z comoving cumulative stellar mass density and the reionization history.

关键词： Cosmology (cosmology:)dark matter (cosmology:)large-scale structure of universe

Flow characteristics and bubble statistics during the fragmentation process of the ingested main cavity in plunging breaking waves

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Journal of Hydrodynamics 2024年第3期36卷 546-555页

作者： Wen-bin Zhang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Plunging breaking waves play an important role in the exchange of heat,momentum,and mass between the atmosphere and *** this paper,a series of direct numerical simulations is conducted to investigate the fragmentation process of the ingested main cavity in plunging breaking *** two-phase Navier-Stokes equations are solved using the finite-volume method based on adaptive refinement *** free surface is captured using a geometrical volume of fluid *** 2-D,3-D simulations are *** flow fields at different stages of wave breaking are presented and quantitative analysis for bubbles is *** 2-D instantaneous vorticity field and local velocity field are visualized to discuss the general flow characteristics during the fragmentation *** a 2-D parametric study is conducted to investigate the differences in the flow characteristics during the fragmentation process under different wave parameters including initial wave steepness(ε),Bond number(Bo),and Reynolds number(Re).3-D vortex structures are shown to further investigate the mechanisms behind the differences in the flow *** bubble size distributions under two different initial wave steepness are also discussed with their relationship to the fragmentation process of the ingested main *** research offers a significant understanding of the distinct procedures and fundamental dynamics involved in wave breaking,enhancing our comprehension of this intricate event.

关键词： Plunging breaking waves multiphase flow bubble statistics