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Detection of a temporal salient object benefits from visual stimulus-specific adaptation in avian midbrain inhibitory nucleus

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Integrative Zoology 2024年第2期19卷 288-306页

作者： Jiangtao WANG Xiaoping RAO Shuman HUANG Zhizhong WANG Xiaoke NIU Minjie ZHU Songwei WANG Li SHI Department of Automation Zhengzhou University School of Electrical EngineeringZhengzhouChina State Key laboratory of magnetic resonance and atomic and molecular physics National Center for Magnetic Resonance in WuhanKey Laboratory of Magnetic Resonance in Biological SystemsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanChina Department of Automation Tsinghua UniversityBeijingChina

Food and predators are the most noteworthy objects for the basic survival of wild animals,and both are often deviant in both spatial and temporal domains and quickly attract an animal’s *** stimulus-specific adaptation(SSA)is considered a potential neural basis of salient sound detection in the temporal domain,related research on visual SSA is limited and its relationship with temporal saliency is *** avian nucleus isthmi pars magnocellularis(Imc),which is central to midbrain selective attention network,is an ideal site to investigate the neural correlate of visual SSA and detection of a salient object in the time ***,the constant order paradigm was applied to explore the visual SSA in the Imc of *** results showed that the firing rates of Imc neurons gradually decrease with repetitions of motion in the same direction,but recover when a motion in a deviant direction is presented,implying visual SSA to the direction of a moving ***,enhanced response for an object moving in other directions that were not presented ever in the paradigm is also *** verify the neural mechanism underlying these phenomena,we introduced a neural computation model involving a recoverable synaptic change with a“center-surround”pattern to reproduce the visual SSA and temporal saliency for the moving *** results suggest that the Imc produces visual SSA to motion direction,allowing temporal salient object detection,which may facilitate the detection of the sudden appearance of a predator.

关键词： adaptation attention model pigeon saliency

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Fluorinated [2]rotaxanes as sensitive 19F MRI agents: Threading for higher sensitivity

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Chinese Chemical Letters 2024年第10期35卷 405-408页

作者： Lan Yang Yu Li Mou Jiang Rui Zhou Hengjiang Cong Minghui Yang Lei Zhang Shenhui Li Yunhuang Yang Maili Liu Xin Zhou Zhong-Xing Jiang Shizhen Chen State Key laboratory of magnetic resonance and atomic and molecular physics National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics School of Pharmaceutical Sciences & College of Chemistry and molecular Sciences Wuhan University University of Chinese Academy of Sciences Optics Valley laboratory

As a promising imaging technology, the low sensitivity of fluorine-19 magnetic resonance imaging(19F MRI) severely hinders its biomedical applications. Herein, we have developed an unprecedented rotaxanebased strategy to improve the sensitivity of19F MRI agents. By threading the fluorinated macrocycle into2-blade pinwheel [2]rotaxanes, the19F longitudinal relaxation rate R1was dramatically increased, resulting in a significant19F MRI signal intensity enhancement of up to 79%. Through comparative molecular dynamics studies using a series of solution and solid-state1H/19F nuclear magnetic resonance(1H/19F NMR) and molecular dynamics simulations, it was found that the formation of mechanical bonds dramatically restricts the motion of the wheel fluorines and thus increasing the R1for higher19F MRI *** a novel strategy for improving19F MRI sensitivity, this study has established19F NMR/MRI as a valuable technology for monitoring the molecular dynamics of rotaxanes, which may shed new light on high-performance19F MRI agents and molecular devices.

关键词： 19F MRI Imaging agent Mechanical bond Relaxation rate Rotaxane

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In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms

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Chinese physics B 2024年第2期33卷 318-323页

作者：郭瑞军何晓东盛诚王坤鹏许鹏刘敏王谨孙晓红曾勇詹明生 Henan Key laboratory of Laser and Optoelectronic Information National Center for International Joint Research of Electronic Materials and SystemsSchool of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China State Key laboratory of magnetic resonance and atomic and molecular physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, especially at a low bias magnetic field strength, for the magic-intensity trapping of85Rb qubits. In this work, we present a method to calibrate the angle between the bias magnetic field and the trapping laser field with the compensating magnetic fields in the other two directions orthogonal to the bias magnetic field direction. Experimentally, with a constantdepth trap and a fixed bias magnetic field, we measure the respective resonant frequencies of the atomic qubits in a linearly polarized trap and a circularly polarized one via the conventional microwave Rabi spectra with different compensating magnetic fields and obtain the corresponding total magnetic fields via the respective resonant frequencies using the Breit–Rabi formula. With known total magnetic fields, the angle is a function of the other two compensating magnetic ***, the projection value of the angle on either of the directions orthogonal to the bias magnetic field direction can be reduced to 0(4)° by applying specific compensating magnetic fields. The measurement error is mainly attributed to the fluctuation of atomic temperature. Moreover, it also demonstrates that, even for a small angle, the effect is strong enough to cause large decoherence of Rabi oscillation in a magic-intensity trap. Although the compensation method demonstrated here is explored for the magic-intensity trapping technique, it can be applied to a variety of similar precision measurements with trapped neutral atoms.

关键词： quantization axis trapping laser angle compensating magnetic fields

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Modulation of zeolite surface realizes dynamic copper species redispersion

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Chinese Journal of Structural Chemistry 2024年第6期43卷 6-7页

作者： Guoliang Liu Zhiqiang Liu Anmin Zheng Interdisciplinary Institute of NMR and molecular Sciences School of Chemistry and Chemical EngineeringThe State Key Laboratory of Refractories and MetallurgyWuhan University of Science and TechnologyWuhan430081PR China State Key laboratory of magnetic resonance and atomic and molecular physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430071PR China

Zeolite-based metal nanoparticles(NPs)catalysts have shown promising applications in fuel production,petro-and fine-chemical manufacture,biomass refinery,and so *** of hydroxyl groups on the zeolite surface has proven to be effective in boosting catalytic reactions over metal-zeolite *** example,modifying the wettability of ZSM-5 and titanium silicalite-1(TS-1)crystals by surface hydrophobization drastically enhances catalytic performance of zeolites encapsulated AuPd[1]and Pt[2]NPs in methane oxidation and aldehydes/ketones hydrogenation,*** fact,two kinds of hydroxyl groups are present in zeolite materials,which refers to bridged hydroxyls[Si-O(H)-Al]and silanols[Si-O(H)].Both hydroxyl groups are defects of zeolite framework structures,which provides anchor points in dispersing metals[3].The former hydroxyl group is tunable to control acidity by adjusting Si/Al ratio in zeolite,whereas the role of silanols is not fully understood[4],particularly in the dispersion of metal NPs.

关键词： zeolite dispersion aldehydes

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Core level excitation spectra of La and Mn ions in LaMnO3

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Chinese physics B 2024年第3期33卷 327-332页

作者：李福建程新路张红 Institute of atomic and molecular physics Sichuan UniversityChengdu 610065Chin

Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic *** this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field *** analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 *** is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ***,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates.

关键词： lanthanum manganate the core level excitation spectra free-ion multiplet calculation oxidation state

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Strong-field photoelectron holography in the subcycle limit

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Light(Science & Applications) 2024年第6期13卷 1032-1040页

作者： Tsendsuren Khurelbaatar Jaewuk Heo ShaoGang Yu XuanYang Lai XiaoJun Liu Dong Eon Kim Center for Attosecond Science and Technology Department of PhysicsPohang University of Science and TechnologyPohangGyeongbuk37673Korea Max Planck POSTECH/KOREA Research Initiative PohangGyeongbuk37673Korea State Key laboratory of magnetic resonance and atomic and molecular physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences430071WuhanChina Wuhan Institute of Quantum Technology 430206WuhanChina

Strong-field photoelectron holography is promising for the study of electron dynamics and structure in atoms and molecules,with superior spatiotemporal resolution compared to conventional electron and X-ray ***,the application of strong-field photoelectron holography has been hindered by inter-cycle interference from multicycle ***,we address this challenge by employing a near-single-cycle field to suppress the inter-cycle *** observed and separated two distinct holographic patterns for the first *** measurements allow us not only to identify the Gouy phase effect on electron wavepackets and holographic patterns but also to correctly extract the internuclear separation of the target molecule from the holographic *** work leads to a leap jump from theory to application in the field of strong-field photoelectron holography-based ultrafast imaging of molecular structures.

关键词： photoelectron holographic cycle

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Building and characterizing a stylus ion-trap system

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Chinese physics B 2024年第4期33卷 122-127页

作者：崔太豪魏雅琪李冀袁泉戴双晴李沛东周飞张建奇郑驻军陈亮冯芒 State Key laboratory of magnetic resonance and atomic and molecular physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of the Chinese Academy of Sciences Beijing 100049China laboratory of Quantum Science and Engineering South China University of TechnologyGuangzhou 510641China Research Center for Quantum Precision Measurement Guangzhou Institute of Industry TechnologyGuangzhou 511458China Department of physics Zhejiang Normal UniversityJinhua 321004China

Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at *** stylus ion trap,formed by two concentric cylinders over a ground plane,holds the promise of relatively simple structure and larger solid angle for optical access and fluorescence collection in comparison with the conventional ion *** we report our fabrication and characterization of the first stylus ion trap constructed in China,aiming for studying quantum optics and sensing weak electric fields in the *** have observed the stable confinement of the ion in the trapping potential for more than two hours and measured the heating rate of the trap to be dε/dt=7.10±0.13 meV/s by the Doppler recooling *** work starts a way to building practical quantum sensors with high efficiency of optical collection and with ultimate goal for contributing to future quantum information technology.

关键词： stylus ion trap electric-field noises Doppler recooling method heating rate

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Chronic sleep deprivation induces alterations in DNA and RNA modifications by liquid chromatography-mass spectrometry analysis

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Chinese Chemical Letters 2024年第8期35卷 413-417页

作者： Tian Feng Yun-Ling Gao Di Hu Ke-Yu Yuan Shu-Yi Gu Yao-Hua Gu Si-Yu Yu Jun Xiong Yu-Qi Feng Jie Wang Bi-Feng Yuan School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Key laboratory of magnetic resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441000China Phase I Clinical Trial laboratory Zhongnan Hospital of Wuhan UniversityWuhan 430071China

Sleep deprivation(SD)is a widespread issue that disrupts the lives of millions of *** effects ini-tiate as changes within neurons,specifically at the DNA and RNA level,leading to disruptions in neuronal plasticity and the dysregulation of various cognitive functions,such as learning and *** acid epigenetic modifications that could regulate gene expression have been reported to play crucial roles in this ***,there is a lack of comprehensive research on the correlation of SD with nucleic acid epigenetic *** the current study,we aimed to systematically investigate the landscape of modifications in DNA as well as in small RNA molecules across multiple tissues,including the heart,liver,kidney,lung,hippocampus,and spleen,in response to chronic sleep deprivation(CSD).Using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis,we characterized the dynamic changes in DNA and RNA modification profiles in different tissues of mice under CSD ***,we ob-served a significant decrease in the level of 5-methylcytosine(5mC)and a significant increase in the level of 5-hydroxymethylcytosine(5hmC)in the kidney in CSD *** RNA modifications,we observed an overall increased trend for most of these significantly changed modifications across six tis-sues in CSD *** study sheds light on the significance of DNA and RNA modifications as crucial epigenetic markers in the context of CSD-induced stress.

关键词： Sleep deprivation Epigenetics Mass spectrometry DNA modification RNA modification Small RNA

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Human islet amyloid polypeptide oligomers stabilized and probed by MAS NMR

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magnetic resonance Letters 2024年第1期4卷 61-62页

作者： Ziwei Chang Zhengfeng Zhang Key laboratory of magnetic resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430071China

The capture and characterization of oligomers are extremely important in the studies of amyloid aggregation of proteins and *** are critical intermediates that can impact the structures of amyloid ***,it is widely accepted that oligomers are the most toxic species along the aggregation pathway[1e4].The studies of oligomers are believed to shed light on the molecular mechanism of amyloid fibrillation and probably the medical clues for related *** vitro investigations of amyloid oligomers are challenging due to their transient and polymorphic nature[5].This is particularly evident in the case of human type-2 diabetes-associated islet amyloid polypeptide(hIAPP),which tends to rapidly form polymorphic fibrils within minutes[6].Notably,hIAPP demonstrates a higher propensity for rapid aggregation compared to other amyloid proteins such as a-synuclein[7].

关键词： aggregation oligomer stabilized

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Optical two-dimensional coherent spectroscopy of excitons in transition-metal dichalcogenides

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Frontiers of physics 2024年第2期19卷 141-148页

作者： YanZuo Chen ShaoGang Yu Tao Jiang XiaoJun Liu XinBin Cheng Di Huang State Key laboratory of magnetic resonance and atomic and molecular physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China MOE Key laboratory of Advanced Micro-Structured Materials Shanghai Frontiers Science Center of Digital OpticsInstitute of Precision Optical Engineeringand School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China

Exciton physics in atomically thin transition-metal dichalcogenides(TMDCs)holds paramount importance for fundamental physics research and prospective ***,the experimental exploration of exciton physics,including excitonic coherence dynamics,exciton many-body interactions,and their optical properties,faces challenges stemming from factors such as spatial heterogeneity and intricate many-body *** this perspective,we elaborate upon how optical two-dimensional coherent spectroscopy(2DCS)emerges as an effective tool to tackle the challenges,and outline potential directions for gaining deeper insights into exciton physics in forthcoming experiments with the advancements in 2DCS techniques and new materials.

关键词： monolayer transition-metal dichalcogenides two-dimensional coherent spectroscopy

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