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Dispersive analysis of low energyγN→πN process and studies on the N^*(890)resonance

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Chinese Physics C 2021年第1期45卷 252-264页

作者： yao ma Wen-Qi Niu De-Liang yao Han-Qing Zheng Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China School of Physics and Electronics Hunan UniversityChangsha 410082China Collaborative Innovation Center of Quantum matter Beijing 100871China

We present a dispersive representation of the γN→πN partial-wave amplitude based on unitarity and *** this representation,the right-hand-cut contribution responsible for πN final-state-interaction effects is taken into account via an Omnes formalism with elastic πN phase shifts as inputs,while the left-hand-cut contribution is estimated by invoking chiral perturbation *** fits are performed to pin down the involved subtraction *** fit quality can be achieved with only one free parameter,and the experimental data regarding the multipole amplitude E0+ in the energy region below the △(1232) are well ***,we extend the γN →μN partial-wave amplitude to the second Riemann sheet to extract the couplings of the N*(890).The modulus of the residue of the multipole amplitude E0+(S11pE) is 2.41 mfm·GeV2,and the partial width of N*(890)→ yN at the pole is approximately 0.369 MeV,which is almost the same as that of the N*(1535) resonance,indicating that N*(890) strongly couples to the πN system.

关键词： dispersive representation nucleon resonance pion photoproduction off the nucleon

How does the S11 N^*(890) state emerge from a naive K-matrix fit?

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Communications in Theoretical Physics 2020年第10期72卷 92-97页

作者： yao ma Wen-Qi Niu Yu-Fei Wang Han-Qing Zheng Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Helmholtz Institut für Strahlen-und Kernphysik University of BonnBonn D-53115Germany Collaborative Innovation Center of Quantum matter BeijingChina

We give a pedagogical analysis on K-matrix models describing theπN scattering amplitude,in S11 channel at low *** show how the correct use of analyticity in the s-channel and crossing symmetry in t-and u-channels leads to a much improved analytic behavior in the negative s region,in agreement with the prediction from chiral perturbation amplitudes in its validity *** analysis leads again to the conclusion that a genuine N^*(890)resonance exists.

关键词： pi N scattering subthreshold pole K-matrix N^*(890)

Simulation of anyons by cold atoms with induced electric dipole moment

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Chinese Physics B 2020年第8期29卷 157-161页

作者： Jian Jing yao-yao ma Qiu-Yue Zhang Qing Wang Shi-Hai Dong College of mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China College of Physics and Technology Xinjiang UniversityUrumqi 830046China Laboratorio de Información Cuántica CIDETECInstituto Politécnico NacionalUPALMCDMX 07700Mexico

We show that it is possible to simulate an anyon by a trapped atom which possesses an induced electric dipole moment in the background of electric and magnetic fields in a specific *** electric and magnetic fields we applied contain a magnetic and two electric *** find that when the atom is cooled down to the limit of the negligibly small kinetic energy,the atom behaves like an anyon because its angular momentum takes fractional *** fractional part of the angular momentum is determined by both the magnetic and one of the electric *** electric and magnetic fields played are analyzed.

关键词： anyons cold atoms induced electric dipole moment

Inhibition of microRNA-29b suppresses oxidative stress and reduces apoptosis in ischemic stroke

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Neural Regeneration Research 2022年第2期17卷 433-439页

作者： yao-Hua ma Wen-Jing Deng Zhi-Yi Luo Jing Jing Peng-Wei Pan yao-Bing yao Yan-Bo Fang Jun-Fang Teng Neurological Intensive Care Unit the First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina

MicroRNAs(miRNAs) regulate protein expression by antagonizing the translation of mRNAs and are effective regulators of normal nervous system development, function, and disease. Micro RNA-29 b(mi R-29 b) plays a broad and critical role in brain homeostasis. In this study, we tested the function of mi R-29 b in animal and cell models by inhibiting mi R-29 b expression. Mouse models of middle cerebral artery occlusion were established using the modified Zea-Longa suture method. Prior to modeling, 50 nmol/kg mi R-29 b antagomir was injected via the tail vein. Mi R-29 b expression was found to be abnormally increased in ischemic brain tissue. The inhibition of mi R-29 b expression decreased the neurological function score and reduced the cerebral infarction volume and cell apoptosis. In addition, the inhibition of mi R-29 b significantly decreased the malondialdehyde level, increased superoxide dismutase activity, and Bcl-2 expression, and inhibited Bax and Caspase3 expression. PC12 cells were treated with glutamate for 12 hours to establish in vitro cell models of ischemic stroke and then treated with the mi R-29 antagomir for 48 hours. The results revealed that mi R-29 b inhibition in PC12 cells increased Bcl-2 expression and inhibited cell apoptosis and oxidative damage. These findings suggest that the inhibition of mi R-29 b inhibits oxidative stress and cell apoptosis in ischemic stroke, producing therapeutic effects in ischemic stroke. This study was approved by the Laboratory Animal Care and Use Committee of the First Affiliated Hospital of Zhengzhou University(approval No. 201709276 S) on September 27, 2017.

关键词： Akt apoptosis cerebral artery occlusion ischemic stroke malondialdehyde microRNA-29b oxidative stress PI3K superoxide dismutase

Disastrous effects of climate change on High Mountain Asia

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Advances in Climate Change Research 2024年第3期15卷 365-366页

作者： Peng CUI yao-Ming ma Yan WANG Bin-BinWANG Institute of Geographic Sciences and Natural Resources Research The Chinese Academy of Sciences(CAS)Beijing 100101China Institute of Mountain Hazards and Environment CASChengdu 610041China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad 45320Pakistan State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchCASBeijing 100101China

High Mountain Asia(Hma),encompassing the Tibetan Plateau and the surrounding high mountain ranges of the Hindu Kush and Tianshan,is a region characterised by large terrain,complex topography and the interplay of vario... 详细信息

关键词： terrain Tianshan Tibetan

Links between winter dust over the Tibetan Plateau and preceding autumn sea ice variability in the Barents and Kara Seas

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Advances in Climate Change Research 2022年第6期13卷 896-908页

作者： Chao XU Jie-Hua ma Jian-Qi SUN Chao YOU yao-Ming ma Hui-Jun WANG Tao WANG Climate Change Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Cma Earth System Modeling and Prediction Centre(CEMC) China Meteorological AdministrationBeijing 100081China Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China College of Environment and Ecology Chongqing UniversityChongqing 400044China Land-Atmosphere Interaction and Its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth System and Resources Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Planetary Sciences University of Chinese Academy of ScienceBeijing 100049China Center for Pan-third Pole Environment Lanzhou UniversityLanzhou 730000China

The Tibetan Plateau(TP)is characterized by heavily local dust activities,however,the mechanism of interannual variations of winter dust frequency over the TP remain poorly *** studies showed the autumn Arctic sea ice could significantly influence the winter climate over *** autumn sea ice affects winter dust activity over the TP or not?Here,we used an integrated surface database to investigate possible mechanisms for interannual variability in the frequency of winter dust events above the *** variability,which is thought to be mainly caused by local dust emissions,shows significant correlations with sea ice concentration(SIC)in the Barents and Kara Seas during the preceding *** Barents-Kara SIC is accompanied by reduced snow depth over northern Eurasia between autumn and winter,which can enhance the Eurasian mid-latitude westerly jet *** strengthening increases the cyclogenesis and occurrence of strong surface wind speeds in winter,especially over the *** addition,a lower SIC is closely associated with reduced precipitation and snow cover in late autumn and winter over the TP,which in turn enhances warming of the land surface and reduces the area of frozen *** anomalies in atmospheric circulation patterns and local surface conditions promote dust events above the TP during *** ensemble means of Atmospheric Model Intercomparison Project experiments from Phase 6 of the Coupled Model Inter-comparison Project and the Community Atmosphere Model version 4 can generally reproduce the atmospheric circulation anomalies associated with decreased Barents-Kara *** study reveals the crucial effect that SIC anomalies in the Barents and Kara Seas have on winter dust activities over the TP.

关键词： Winter dust frequency Tibetan Plateau Sea ice concentration Barents and Kara Seas Snow anomalies

Advances in perovskite photodetectors

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Infomat 2020年第6期2卷 1247-1256页

作者： Chenglong Li yao ma Yifan Xiao Liang Shen Liming Ding State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchunChina Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijingChina

Perovskite photodetectors have gradually shown preeminent photoelectric performance due to the unique material *** recent years,lots of works have been reported in improving the sensitivity,changing detection spectrum range and enhancing long-term ***,we summarize the some efficient strategies for performance improvement and synchronously analyze severe issues exposed in ***,some reasonable proposals are put forward to solve future predicted *** addition,more prospective assumptions are proposed on the basis of the development trend in photoelectric detection *** hope this perspective will allow researchers to have a clearer understanding of recent studies based on perovskite photodetectors and inspire more meaningful work in the future.

关键词： detectivity perovskite photodetectors response speed stability

Electrochemical reduction of graphene oxide films:Preparation,characterization and their electrochemical properties

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Chinese Science Bulletin 2012年第23期57卷 3045-3050页

作者： ZHANG Xiong ZHANG DaCheng CHEN yao SUN XianZhong ma YanWei Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Graphene oxide (GO) film was electrochemically reduced by a cyclic voltammetry technique in 6 mol L-1 KOH aqueous *** reduced graphene oxide (ER-GO) film was characterized by X-ray diffraction,X-ray photoelectron spectroscopy,atomic force microscopy,and Raman *** oxygen content (with the O/C atomic ratio of 1.29%) was significantly decreased after electrochemical *** ER-GO film exhibited a specific capacitance of 152 F g-1 at the current density of 5 A g-1 and a good rate ***,the ER-GO film showed an excellent cycling *** capacitance retention remained 99% after 3000 cycles at the current density of 10 A g-1.

关键词： graphene, electrochemical reduction, electrochemical double-layer capacitor, electrode material

On Hom-groups and Hom-group Actions

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Acta mathematica Sinica,English Series 2023年第10期39卷 1887-1906页

作者： Liang Yun CHEN Tian Qi FENG yao ma Ripan SAHA Hong Yi ZHANG School of mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of mathematics Raiganj UniversityRaiganj 733134West BengalIndia School of mathematical Sciences Nankai UniversityTianjin 300071P.R.China

A Hom-group is the non-associative generalization of a group whose associativity and unitality are twisted by a compatible bijective *** this paper,we give some new examples of Hom-groups,and show the first,second and third isomorphism theorems of *** also introduce the notion of Hom-group action,and as an application,we prove the first Sylow theorem for Hom-groups along the line of group actions.

关键词： Hom-groups Hom-subgroups Hom-quotient groups isomorphism Hom-group actions first Sylow theorem