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Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex 被引量:1
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作者 Zongqin Xiang Shu He +13 位作者 Rongjie Chen Shanggong Liu Minhui Liu Liang Xu Jiajun Zheng Zhouquan Jiang long ma Ying Sun Yongpeng Qin Yi Chen Wen Li Xiangyu Wang Gong Chen Wenliang Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1781-1788,共8页
Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for ... Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction. 展开更多
关键词 astrocyte-to-neuron conversion Ca2+imaging direct lineage conversion GLIA ASTROCYTE in vivo reprogramming lineage-tracing mice NeuroD1 NEURON two-photon imaging
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Low-energy spin dynamics in a Kitaev material Na_(3)Ni_(2)BiO_(6) investigated by nuclear magnetic resonance
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作者 史昕雨 崔祎 +11 位作者 上官艳艳 徐霄宇 吴占龙 胡泽 李硕 杜柯帆 陈颖 马龙 刘正鑫 温锦生 张金珊 于伟强 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期518-524,共7页
We perform ^(23)Na nuclear magnetic resonance(NMR) and magnetization measurements on an S=1,quasi-2D honeycomb lattice antiferromagnet Na_(3)Ni_(2)BiO_(6).A large positive Curie-Weiss constant of 22.9 K is observed.Th... We perform ^(23)Na nuclear magnetic resonance(NMR) and magnetization measurements on an S=1,quasi-2D honeycomb lattice antiferromagnet Na_(3)Ni_(2)BiO_(6).A large positive Curie-Weiss constant of 22.9 K is observed.The NMR spectra at low fields are consistent with a zigzag magnetic order,indicating a large easy-axis anisotropy.With the field applied along the c*axis,the NMR spectra confirm the existence of a 1/3-magnetization plateau phase between 5.1 T and 7.1 T.The transition from the zigzag order to the 1/3-magnetization plateau phase is also found to be a first-order type.A monotonic decrease of the spin gap is revealed in the 1/3-magnetization plateau phase,which reaches zero at a quantum critical field H_(C)≈8.35 T before entering the fully polarized phase.These data suggest the existence of exchange frustration in the system along with strong ferromagnetic interactions,hosting the possibility for Kitaev physics.Besides,well below the ordered phase,the 1/T_(1) at high fields shows either a level off or an enhancement upon cooling below 3 K,which suggests the existence of low-energy fluctuations. 展开更多
关键词 one–third magnetization plateau phase nuclear magnetic resonance honeycomb-lattice antiferromagnet Kitaev interaction
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Production and test of sPHENIX W/SciFiber electromagnetic calorimeter blocks in China
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作者 Xiao‑Zhou Yu Xi‑Yang Wang +11 位作者 Wei‑Hu ma Shi‑Hong Fu Peng‑Fei Sun Jin‑Xing Song Wan‑Bing He Yang Shen long ma Jin‑Hui Chen Huan‑Zhong Huang Si‑Guang Wang Jing Zhou Xiao‑Mei Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期167-176,共10页
The sPHENIX experiment is a new generation of large acceptance detectors at the relativistic heavy ion collider at Brookhaven National Laboratory,with scientific goals focusing on probing the strongly interacting Quar... The sPHENIX experiment is a new generation of large acceptance detectors at the relativistic heavy ion collider at Brookhaven National Laboratory,with scientific goals focusing on probing the strongly interacting Quark–Gluon plasma with hard probes of jets,open heavy flavor particles,andγproduction.The EMCal detector,which covers the pseudo-rapidity region of|η|≤1.1,is an essential subsystem of sPHENIX.In this study,we focused on producing and testing EMCal blocks covering a pseudo-rapidity of|η|∈[0.8,1.1].These,in conjunction with the central pseudo-rapidity EMCal blocks,significantly enhance the sPHENIX physics capability of the jet andγparticle measurements.In this paper,the detector module production and testing of sPHENIX W-powder/scintillating fiber(W/ScFi)electromagnetic calorimeter blocks are presented.The selection of the tungsten powder,mold fabrication,QA procedures,and cosmic ray test results are discussed. 展开更多
关键词 sPHENIX Tungsten/scintillating fiber electromagnetic calorimeter Cosmic ray test
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Characteristics of gravity anomalies and tectonic analysis of Enderby Land in East Antarctica and its adjacent areas
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作者 long ma Chenguang Liu +2 位作者 An Yang Baohua Liu Chenglong Xia 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期94-103,共10页
Enderby Land in East Antarctica and its adjacent areas,which are closely related to the Indian Plate in their geological evolution,have become one of the key zones for studies on how the Antarctic continent evolves.Ba... Enderby Land in East Antarctica and its adjacent areas,which are closely related to the Indian Plate in their geological evolution,have become one of the key zones for studies on how the Antarctic continent evolves.Based on the isostasy and flexure theories of the lithosphere and using the CRUST1.0 model as the depth constraint,this paper uses the gravity field model EIGEN-6C4 and topographic data to calculate the isostatic gravity anomalies of Enderby Land and its adjacent areas.Then,the crustal thickness of the study area is calculated,and three comprehensive geophysical interpretation profiles that vertically span the study area are plotted.The results show that the flexural isostatic gravity anomalies in Enderby Land and its adjacent areas are closely related to the regional tectonic setting,and the anomalies in different regions differ substantially,ranging from−50×10^(−5)m/s^(2)to 85×10^(−5)m/s^(2).A zone of high isostatic gravity anomalies(30×10^(−5)−80×10^(−5)m/s^(2))is distributed outside the Cooperation Sea and Queen Maud Land,which may be plate remnants generated by early rifting.Except for the Kerguelen Plateau,which was formed by a hotspot and has a crustal thickness of 15 km,the thickness of the oceanic crust in other parts of the study area changes slightly by approximately 4–9 km,with the thinnest part being in Enderby Basin.The thickness of the inland crust along the coastline increases with the elevation,with the maximum thickness reaching 34 km.The isostatic gravity anomalies corresponding to the zone of high magnetic anomalies along the continental margin of Queen Maud Land are negative and small,with an isostatic adjustment trend indicating Moho surface uplift,and those on the edge of central Enderby Land are near zero,approaching the isostatic state,which may be caused by the magmatism at the early stage of rifting.The continental-oceanic boundary should be close to the contour line of the crustal thickness 10–12 km on the outer edge of the coastline. 展开更多
关键词 Enderby Land and its adjacent areas flexural isostatic gravity anomalies crustal structure isostatic adjustment
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Gamma-,neutron-,and muon-induced environmental background simulations for 100Mo-based bolometric double-beta decay experiment at Jinping Underground Laboratory
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作者 Wei Chen long ma +1 位作者 Jin-Hui Chen Huan-Zhong Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第9期50-57,共8页
The sensitivity of an experiment to detect the Majorana neutrino mass via neutrinoless double-beta decay(0νββ) strongly depends on the rate of background events that can mimic this decay. One major source of this b... The sensitivity of an experiment to detect the Majorana neutrino mass via neutrinoless double-beta decay(0νββ) strongly depends on the rate of background events that can mimic this decay. One major source of this background is the radioactive emissions from the laboratory environment. In our study, we focused on assessing the background contributions from environmental gamma rays, neutrons, and underground muons to the Jinping bolometric demonstration experiment. This experiment uses an array of lithium molybdate crystal bolometers to probe the potential 0νββ decay of the100Mo isotope at the China Jinping Underground Laboratory. We also evaluated the shielding effectiveness of the experimental setup through an attenuation study. Our simulations indicate that the combined background from environmental gamma rays, neutrons, and muons in the relevant100Mo 0νββ Q-value region can be reduced to approximately 0.003 cts/kg/keV/yr. 展开更多
关键词 Neutrinoless double-beta decay GEANT4 CUPID
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Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature 被引量:3
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作者 Cuiping Li Dan Li +4 位作者 Shuai Zhang long ma Lei Zhang Jingwei Zhang Chunhong Gong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期147-160,共14页
Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently... Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering. 展开更多
关键词 TiN nanotubes Interface engineering Polarization loss Impedance matching Electromagnetic wave absorption performance
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The research progress of an E//B neutral particle analyzer 被引量:1
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作者 马龙 屈玉凡 +12 位作者 罗圆 谢德豪 汪彦熹 王硕 曲国峰 任培培 罗小兵 刘星泉 韩纪锋 Roy WADA 林炜平 臧临阁 朱敬军 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期10-16,共7页
An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of ... An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of fast ions in the HL-2A/3 tokamak.The E//B NPA contains three main units,i.e.the stripping unit,the analyzing unit and the detection unit.A gas stripping chamber was adopted as the stripping unit.The results of the simulations and beam tests for the stripping chamber are presented.Parallel electric and magnetic fields provided by a NdFeB permanent magnet and two parallel electric plates were designed and constructed for the analyzing unit.The calibration of the magnetic and electric fields was performed using a 50 kV electron cyclotron resonance ion source(ECRIS)platform.The detection unit consists of 32lutetium-yttrium oxyorthosilicate(LYSO)detector modules arranged in two rows.The response functions ofα,hydrogen ions(H^(+),H_(2)^(+)and H_(3)^(+))andγfor a detector module were measured with^(241)Am,^(137)Cs and^(152)Eu sources together with the 50 kV ECRIS platform.The overall results indicate that the designed E//B NPA device is capable of measuring the intensity of neutral hydrogen and deuteron atoms with energy higher than 20 keV. 展开更多
关键词 E//B neutral particle analyzer gas stripping lutetium-yttrium oxyorthosilicate electron cyclotron resonance ion source platform
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Spatial distribution of soil moisture,salinity and organic matter in Manas River watershed,Xinjiang,China 被引量:9
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作者 Jilili ABUDUWAILI Yang TANG +2 位作者 Mireban ABULIMITI DongWei LIU long ma 《Journal of Arid Land》 SCIE 2012年第4期441-449,共9页
With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas ... With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas River watershed. The results showed that the soil moisture data from all soil layers exhibited a normal distribution, with average values of 14.08%-21.55%. Geostatistical analysis revealed that the content of soil moisture had a moder- ate spatial autocorrelation with the ratios of nugget/sill ranging from 0.500 to 0.718, which implies that the spatial pattern of soil moisture is influenced by the combined effects of structural factors and random factors. Remarkable spatial distributions with stripped and mottled features were found for soil moisture in all different soil layers. The landform and crop planting had a relatively big influence on the spatial distribution of soil moisture; total soil salinity was high in east but low in west, and non-salinized soil and lightly salinized soil appeared at the northwest and southwest of the study area. Under the effect of reservoir leakage, the heavily salinized soils are widely distributed in the middle of the study area. The areas of the non-salinized and lightly salinized soils decreased gradually with soil depth increment, which is contrary to the case for saline soils that reached a maximum of 245.67 km2 at the layer of 50-70 cm. The types of soil salinization in Manas River watershed were classified into four classes: the sulfate, chloride-sulfate, sulfate-chloride and chloride. The sulfate salinized soil is most widely distributed in the surface layer. The areas of chloride-sulfate, sulfate-chloride, and chloride salinized soils increased gradually along with the increment of soil depth; the variation range of the average values of soil organic matter content was be- tween 7.48%-11.33%. The ratios of nugget/sill reduced gradually from 0.698 to 0.299 with soil depth increment, which shows that the content of soil organic matter has a moderate spatial autocorrelation. The soil organic matter in all soil layers met normal distribution after logarithmic transformation. The spatial distribution patterns of soil or- ganic matter and soil moisture were similar; the areas with high organic matter contents were mainly distributed in the south of the study area, with the lowest contents in the middle. 展开更多
关键词 soil water and salt organic matter spatial distribution Manas River watershed
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The climatic and hydrological changes and environmental responses recorded in lake sediments of Xinjiang,China 被引量:6
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作者 long ma JingLu WU Jilili Abuduwaili 《Journal of Arid Land》 SCIE 2011年第1期1-8,共8页
Based on the analyses of environmental proxy data in lake sediments and instrumental records of Xinjiang in northwest China, the Holocene climate and hydrological variability and its environmental responses were studi... Based on the analyses of environmental proxy data in lake sediments and instrumental records of Xinjiang in northwest China, the Holocene climate and hydrological variability and its environmental responses were studied in different time scales and regions. The results showed that the Holocene climate variability had obvious differences between the north and south of Xinjiang. In northern Xinjiang, the Holocene climate was dry in the early period, humid in the middle period, and then changed to dry in the late period. However, the climate transition times were not consistent in different regions. In southern Xin- jiang, although there were many different types of climate change patterns inferred from different catch- ments, the warm and wet climate was recorded in most lake sediments in the middle Holocene. According to comparisons of some millennium scale records in lake sediments, the climate was warm and dry in the past 100 years. It can be concluded the climate showed a trend of aridity in Holocene. Especially in recent 50 years, the lake area has been shrinking rapidly because of the population growth and social economic development, which brings some environmental problems. Lake level and area changes were sensitively affected by the climate variation in geological history of Xinjiang and the lake level will continue to shrink because of the drought climate and strengthened human activities. 展开更多
关键词 HOLOCENE climate variation lake level lake sediment arid environment
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Involvement of NLRP3-inflammasome pathway in noise-induced hearing loss 被引量:3
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作者 Na Sai Yuan-Yuan Yang +4 位作者 long ma Da Liu Qing-Qing Jiang Wei-Wei Guo Wei-Ju Han 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第12期2750-2754,共5页
The inflammasome is a multiprotein oligomer in the cell cytoplasm and is part of the innate immune system.It plays a crucial role in the pathological process of noise-induced hearing loss(NIHL).However,the mechanisms ... The inflammasome is a multiprotein oligomer in the cell cytoplasm and is part of the innate immune system.It plays a crucial role in the pathological process of noise-induced hearing loss(NIHL).However,the mechanisms of NLR family pyrin domain containing 3(NLRP3)inflammasome activation in NIHL have not been clearly demonstrated.In this study,miniature pigs were exposed to white noise at 120 dB(A)and auditory brainstem response measurements were used to measure their hearing function.Immunofluorescence staining,confocal laser scanning microscopy,western blot assay,and quantitative reverse transcription-polymerase chain reaction were used to analyze inflammasome-related protein distribution and expression.NLRP3,interleukin-1β,interleukin-18,and cleaved-caspase-1 were highly expressed in the cochlea after 120 dB(A)white noise exposure.Our findings suggest that NLRP3-inflammasomes in the cochlea may be activated after acoustic trauma,which may be an important mechanism of noise-induced hearing loss. 展开更多
关键词 acoustic injury INFLAMMASOME INTERLEUKIN-1Β miniature pig NLR family pyrin domain containing 3(NLRP3) noise-induced hearing loss sensorineural hearing loss
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Alignment calibration and performance study of the STAR PXL detector 被引量:2
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作者 long ma Xin Dong +2 位作者 Hao Qiu Spiros margetis Yu-Gang ma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第2期61-69,共9页
We report in this paper the alignment calibration of the STAR pixel detector(PXL) prototype for the RHIC2013 run and performance study of the full PXL detector installed and commissioned in the RHIC 2014 run. PXL dete... We report in this paper the alignment calibration of the STAR pixel detector(PXL) prototype for the RHIC2013 run and performance study of the full PXL detector installed and commissioned in the RHIC 2014 run. PXL detector is the innermost two silicon layers of the STAR heavy flavor tracker aiming at high-precision reconstruction of secondary decay vertex of heavy flavor particles. To achieve the physics goals, the calibration work was done on the detector with high precision. A histogram-based method was successfully applied for the alignment calibration, and the detector efficiency after alignment was studied using both p t p collision data and cosmic ray data. 展开更多
关键词 ALIGNMENT CALIBRATION Heavy FLAVOR TRACKER STAR
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Explicit Symplectic Geometric Algorithms for Quaternion Kinematical Differential Equation 被引量:1
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作者 Hong-Yan Zhang Zi-Hao Wang +3 位作者 Lu-Sha Zhou Qian-Nan Xue long ma Yi-Fan Niu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第2期479-488,共10页
Solving quaternion kinematical differential equations(QKDE) is one of the most significant problems in the automation, navigation, aerospace and aeronautics literatures. Most existing approaches for this problem neith... Solving quaternion kinematical differential equations(QKDE) is one of the most significant problems in the automation, navigation, aerospace and aeronautics literatures. Most existing approaches for this problem neither preserve the norm of quaternions nor avoid errors accumulated in the sense of long term time. We present explicit symplectic geometric algorithms to deal with the quaternion kinematical differential equation by modelling its time-invariant and time-varying versions with Hamiltonian systems and adopting a three-step strategy. Firstly,a generalized Euler's formula and Cayley-Euler formula are proved and used to construct symplectic single-step transition operators via the centered implicit Euler scheme for autonomous Hamiltonian system. Secondly, the symplecticity, orthogonality and invertibility of the symplectic transition operators are proved rigorously. Finally, the explicit symplectic geometric algorithm for the time-varying quaternion kinematical differential equation, i.e., a non-autonomous and non-linear Hamiltonian system essentially, is designed with the theorems proved. Our novel algorithms have simple structures, linear time complexity and constant space complexity of computation. The correctness and efficiencies of the proposed algorithms are verified and validated via numerical simulations. 展开更多
关键词 Index Terms-Linear time-varying system navigation system quaternion kinematical differential equation (QKDE) real-timecomputation symplectic method.
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Comment on “Outcomes of different minimally invasive surgical treatments for vertebral compression fractures: An observational study”
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作者 long ma Zhi-Wen Luo Ya-Ying Sun 《World Journal of Clinical Cases》 SCIE 2022年第12期3966-3968,共3页
Recently we read the article entitled“Outcomes of different minimally invasive surgical treatments for vertebral compression fractures:An observational study”.This was an observational study that reviewed the safety... Recently we read the article entitled“Outcomes of different minimally invasive surgical treatments for vertebral compression fractures:An observational study”.This was an observational study that reviewed the safety and efficacy of different cement augmentation modalities for vertebral compression fractures under osteoporotic condition.Overall,this is a valuable study that can provide a reference for clinical practice.On the other hand,we also noticed some points in the article and are willing to share our views.Further studies with a higher level of evidence can add more knowledge regarding relevant concerns. 展开更多
关键词 Vertebral compression fractures OSTEOPOROSIS Study design Observational study Randomize
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Incommensurate Magnetic Order in Sm_(3)BWO_(9)with Distorted Kagome Lattice
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作者 Kai-Yue Zeng Fang-Yuan Song +5 位作者 Lang-Sheng Ling Wei Tong Shi-Liang Li Zhao-Ming Tian long ma Li Pi 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第10期39-44,共6页
We investigate the magnetic ground state of Sm_(3)BWO_(9)with a distorted kagome lattice.A magnetic phase transition is identified at T_(N)=0.75 K from the temperature dependence of specific heat.From 11B nuclear magn... We investigate the magnetic ground state of Sm_(3)BWO_(9)with a distorted kagome lattice.A magnetic phase transition is identified at T_(N)=0.75 K from the temperature dependence of specific heat.From 11B nuclear magnetic resonance measurements,an incommensurate magnetic order is shown by the double-horn type spectra under a c-axis magnetic field,and absence of line splitting is observed for field oriented within the ab-plane,indicating the incommensurate modulation of the internal field strictly along𝑐c-axis.From the spin dynamics,the critical slowing-down behavior is observed in the temperature dependence of 1/T_(1)with𝜇_(μ0)H⊥c-axis,which is completely absent in the case with𝜇_(μ0)H||c-axis.Based on the local symmetry of 11B sites,we analyze the hyperfine coupling tensors and propose two constraints on the possible magnetic structure.The single ion anisotropy should play an important role in determination of contrasting ground states of Sm_(3)BWO_(9) and Pr_(3)BWO_(9). 展开更多
关键词 STRUCTURE incommensurate SYMMETRY
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ORPOM model for optimum distribution of tree ring sampling based on the climate observation network
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作者 long ma TingXi Liu +3 位作者 YanYun Luo HongLan Ji ShiQiang Li JunXiao Shi 《Research in Cold and Arid Regions》 2010年第6期547-554,共8页
Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree... Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this article.In this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main principle.Taking the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme. 展开更多
关键词 CLIMATE monitoring network tree ring sampling site optimum model Horqin Sandy Land
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Effect of climatic change on surface environments in the typical region of Horqin Sandy Land
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作者 long ma TingXi Liu +2 位作者 HongLan Ji YanYun Luo LiMin Duan 《Research in Cold and Arid Regions》 2010年第2期143-153,共11页
The town of Agura,a typical region in Horqin Sandy Land,was selected as the study area in this paper.Using 12 remote sensing images and climatic data from the past 20 years,the effects of climate change on surface env... The town of Agura,a typical region in Horqin Sandy Land,was selected as the study area in this paper.Using 12 remote sensing images and climatic data from the past 20 years,the effects of climate change on surface environments were analyzed.The impact indices of climatic factors,along with their corresponding ranks,were used to characterize the responses of different types of surface environments to climate change.Results show that in the past 20 years,the surface environments of the study area have been deteriorating.Furthermore,there is a positive relationship between the changes in surface environments and those in climatic factors.Various climatic factors influence surface environments in different ways and at different levels.The most sensitive factor is relative humidity,followed by precipitation and evaporation.Overall,moisture is the key factor that affects the changes in surface environments of arid and semi-arid areas. 展开更多
关键词 Horqin Sandy Land typical region surface environment climatic change RESPONSE climatic factor impact index
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Comparative Analysis of Nutritional Components in Muscles between Wild and Cultured Masu Salmon Oncorhynchus masou
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作者 Kai WEI Wei ZHENG +2 位作者 Yan GENG long ma Chunshan CHEN 《Asian Agricultural Research》 2021年第1期64-67,74,共5页
In this paper,approximate nutritional components and amino acid content were determined in muscles of female wild population(WP)with body weight of 2500-3000 g and female cultured population(CP)with body weight of 750... In this paper,approximate nutritional components and amino acid content were determined in muscles of female wild population(WP)with body weight of 2500-3000 g and female cultured population(CP)with body weight of 750-1250 g masu salmon Oncorhynchus masou in the gonadal development stage IV by conventional method.The results showed that there were significantly higher crude protein and significantly lower crude fat in fresh muscle of WP than that in CP(P<0.05),but not significant differences in the contents of moisture and crude ash between WP and CP(P>0.05).Eighteen kinds of amino acids were detected in muscles of WP and CP,with higher total content of amino acids(TAA),essential amino acids(EAA)and four kinds of delicious amino acids(DAA)in WP than those in CP(P<0.05).The amino acid score(AAS)and chemical score(CS)revealed that the first limiting amino acid was tryptophan in two populations,with essential amino acid index(EAAI)of 75.59%in WP and 70.77%in CP.The findings indicated that the amino acid contents in muscles of CP are lower than that of WP,but the amino acid nutritional value evaluation indicators of both populations are very close,and both have high nutritional value. 展开更多
关键词 Oncorhynchus masou Wild population Cultured population Amino acid composition
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A highly effective incubation strategy enhanced the urban bird hatch success
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作者 long ma Yuancheng Liu +9 位作者 Wenjing Lu Zheng Zhang Wanyou Li Ziwei Zhang Xueli Zhang Chaoying Zhu Junpeng Bai Zhifeng Xu Yuqing Han Luzhang Ruan 《Avian Research》 SCIE CSCD 2023年第1期25-32,共8页
Urbanization is currently considered one of the most rapid types of global environmental change.Urban habitats are biotically and abiotically different from their rural areas,i.e.,the ambient temperature,predator,and ... Urbanization is currently considered one of the most rapid types of global environmental change.Urban habitats are biotically and abiotically different from their rural areas,i.e.,the ambient temperature,predator,and food availability.These novel challenges create new selection pressures,which allow one to investigate ecoevolutionary responses to contemporary environmental change.A total of 118 breeding nests were monitored for nest predation in both urban and rural areas from 2018 to 2020.We used environmental factors from urban and rural areas and behavioral data from 439 Chinese Blackbird(Turdus mandarinus)valid incubation days to understand the impact of urbanization on the incubation behavior of blackbirds and its adaptation mechanism to the urban environment.Cities have warmer ambient temperatures and lower predation pressures than rural areas.Urban blackbirds chose the incubation strategy with shorter and more bouts,while rural blackbirds selected the incubation strategy with longer and fewer bouts.The plasticity of incubation behavior of urban blackbirds was higher than that of rural areas,and the range of egg temperature was also higher than that of rural areas.In addition,incubation temperature and the number of bouts per day were the key factors affecting the day survival rate of blackbirds,and the hatching rate of urban blackbirds was higher than that of rural blackbirds.Our results provide evidence for behavioral shifts in blackbirds during adaptation to urbanization and support the central role of behavioral adaptation in the successful colonization of new environments by wildlife.These help us understand the behavioral characteristics required for wildlife to live in cities and the urban adaptors faced environmental pressures. 展开更多
关键词 Ambient temperature Inaubation behavior Parental care Phenotypic plasticity Predation risk
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Distributed Containment Control of Networked Nonlinear Second-order Systems With Unknown Parameters 被引量:3
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作者 long ma Haibo Min +2 位作者 Shicheng Wang Yuan Liu Zhiguo Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第1期232-239,共8页
In this paper, we study the containment control problem for nonlinear second-order systems with unknown parameters and multiple stationary/dynamic leaders. The topologies that characterize the interaction among the le... In this paper, we study the containment control problem for nonlinear second-order systems with unknown parameters and multiple stationary/dynamic leaders. The topologies that characterize the interaction among the leaders and the followers are directed graphs. Necessary and sufficient criteria which guarantee the control objectives are established for both stationary leaders(regulation case) and dynamic leaders(dynamic tracking case) based protocols. The final states of all the followers are exclusively determined by the initial values of the leaders and the topology structures. In the regulation case, all the followers converge into the convex hull spanned by the leaders,while in the dynamic tracking case, not only the positions of the followers converge into the convex hull but also the velocities of the followers converge into the velocity convex hull of the leaders.Finally, all the theoretical results are illustrated by numerical simulations. 展开更多
关键词 Containment control directed network topology multi-agent systems nonlinear second-order systems
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Study of a background reconstruction method for the measurement of D-meson azimuthal angular correlations 被引量:3
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作者 long ma Xin Dong +1 位作者 Huan-Zhong Huang Yu-Gang ma 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第6期63-69,共7页
We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA simulation.The like-sign(LS)and side-band(SB)background methods,which are widely used in the experiment... We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA simulation.The like-sign(LS)and side-band(SB)background methods,which are widely used in the experimental measurements of single D-meson production yields,were deployed for correlation study.It was found that the LS method,which describes the combinatorial background of single D^(0) meson yields,fails to reproduce the correlated background in the D^(0)-D^(0) correlation measurement,while the SB background method yields a good description of the background for both single D^(0) yields and the correlated background of the D^(0)-D^(0) correlation measurement.We further examined the validity of the correlation methods under different signal-to-background ratios,providing direct references for experimental measurements. 展开更多
关键词 Heavy flavor Azimuthal correlation PYTHIA
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