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Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun ren Jiang Yu Jing Wang ZuZheng Chen XiaoMan Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

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Influencing factors of fear of falling among glaucoma patients in west China:a cross-sectional study

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International Journal of Ophthalmology(English edition) 2023年第4期16卷 563-570页

作者： Jie ren xin Zhang Hong Lin Ji-Hong zeng Department of Ophthalmology West China HospitalSichuan University/West China School of NursingSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To investigate the current situation and influencing factors of fear of falling in glaucoma patients in western ***:In this cross-sectional study,glaucoma patients treated in the Ophthalmology Department of West China Hospital of Sichuan University were conducted to investigate the demographic data,visual acuity,visual field,activities of daily living,risk of falling,fear of falling and psychological *** linear model was used for multivariate analysis with fear of falling as dependent variable and other factors as independent ***:The mean score of the Chinese version modified Fall Efficacy Scale(MFES)was 7.52±2.09 *** analysis and multivariate analysis showed that the history of falls within one year,visual acuity,visual field,risk of falling,activities of daily living and psychological states had statistically difference on fear of falling(P<0.05).CONCLUSION:Glaucoma patients in west China have relatively high risk of fear of *** of falling within 1y,severe visual function impairment,high risk of falling,incapable of independence of daily living,and abnormal psychological state are risk factors of fear of falling among glaucoma patients.

关键词： glaucoma fear of falling influencing factors

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Influencing factors of self-management ability among dry eye patients in west China

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1621-1627页

作者： Jie ren xin Zhang Ji-Hong zeng Yun-Xia Gao Department of Ophthalmology West China HospitalSichuan University/West China School of NursingSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To investigate the current situation and influencing factors of self-management ability in dry eye patients in west ***:A total of 265 patients clinically diagnosed with dry eye received a convenience survey questionnaire at West China Hospital of Sichuan *** participants completed the rating scale of health self-management skill for adults(AHSMSRS),Huaxi Emotional-Distress Index(HEI),e-health literacy scale(e-HEALS)and Brief Illness Perception Questionnaire(Brief-IPQ).A generalized linear model was employed to establish a multivariate linear model with demographic data,psychological state,e-HEALS,and illness perception as independent variables and health selfmanagement skill score as the dependent ***:The mean score for health self-management skill was 165.58±*** analysis revealed that advanced age,better illness perception and improved psychological state were associated with better health selfmanagement ability among dry eye ***,the health self-management ability of patients with a disease duration less than 1y was found to be higher compared to those with a disease duration exceeding ***:The health self-management ability of dry eye patients in west China is relatively ***,duration of disease,illness perception and psychological state are the influencing factors on the health selfmanagement ability of dry eye patients.

关键词： dry eye self-management ability influencing factors

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Deep reinforcement learning using least-squares truncated temporal-difference

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 425-439页

作者： Junkai ren Yixing Lan xin Xu Yichuan Zhang Qiang Fang Yujun zeng College of Intelligence Science and Technology National University of Defense TechnologyChangshaChina State Key Laboratory of Astronautic Dynamics Xi'an Satellite Control CenterXi'anChina

Policy evaluation(PE)is a critical sub-problem in reinforcement learning,which estimates the value function for a given policy and can be used for policy ***,there still exist some limitations in current PE methods,such as low sample efficiency and local convergence,especially on complex *** this study,a novel PE algorithm called Least-Squares Truncated Temporal-Difference learning(LST2D)is *** LST2D,an adaptive truncation mechanism is designed,which effectively takes advantage of the fast convergence property of Least-Squares Temporal Difference learning and the asymptotic convergence property of Temporal Difference learning(TD).Then,two feature pre-training methods are utilised to improve the approximation ability of ***,an Actor-Critic algorithm based on LST2D and pre-trained feature representations(ACLPF)is proposed,where LST2D is integrated into the critic network to improve learning-prediction *** simulation studies were conducted on four robotic tasks,and the corresponding results illustrate the effectiveness of *** proposed ACLPF algorithm outperformed DQN,ACER and PPO in terms of sample efficiency and stability,which demonstrated that LST2D can be applied to online learning control problems by incorporating it into the actor-critic architecture.

关键词： Deep reinforcement learning policy evaluation temporal difference value function approximation

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T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1277-1292页

作者： Yuxiao Zheng Zilin ren Ying Liu Juntang Yan Congai Chen Yanhui He Yuyu Shi Fafeng Cheng Qingguo Wang Changxiang Li Xueqian Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Library Beijing University of Chinese MedicineBeijingChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue *** the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the *** an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune *** review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic *** found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic ***1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain ***2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain *** interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke *** trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic ***,such studies have been relatively infrequent,and clinical experience is still *** summary,in ischemic stroke,T cell subsets and activated micro

关键词： brain immune inflammation interaction ischemic stroke mechanism microglia neuron secondary injury T cells

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A solution to the puzzling symbiotic X-ray system 4U 1700+24

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Research in Astronomy and Astrophysics 2014年第6期14卷 617-624页

作者： ren-xin Xu School of Physics and State Key Laboratory of Nuclear Physics and Technology and Kavli Institute for Astronomy and Astrophysics Peking University

A circumstellar corona is proposed to explain a strange quark-cluster star during an accretion phase, which could be essential for understanding the observa- tions of the puzzling symbiotic X-ray system 4U 1700＋24. The state of cold matter at supranuclear density is still an important matter of debate, and one of the con- sequences of a strange star acting as a pulsar is the self-bound phenomenon on the surface, which makes extremely low-mass compact objects unavoidable. In principle, both the redshifted O VIII Ly-c~ emission line and the change in the blackbody radi- ation area could naturally be understood if 4U 1700＋24 is a low-mass quark-cluster star which exhibits wind accretion.

关键词： pulsars: individual (4U 1700+24) -- dense matter -- stars: neutron

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Toward an Understanding of the Periastron Puzzle of PSR B1259-63

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 572-578页

作者： ren-xin Xu Department of Astronomy School of Physics Peking University Beijing 100871

Efforts are made to understand the timing behaviors （e.g., the jumps in the projected pulsar semimajor axis at the periastron passages） observed in the 13-year monitoring of PSR B1259-63. Planet-like objects are suggested to orbit around the Be star, which may gravitationally perturb the （probably low mass） pulsar when it passes through periastron. An accretion disk should exist outside the pulsar＇s light cylinder, which creates a spindown torque on the pulsar due to the propeller effect. The observed negative braking index and the discrepant timing residuals close to periastron could be related to the existence of a disk with a varying accretion rate. A speculation is presented that the accretion rate may increase on a long timescale in order to explain the negative braking index.

关键词： pulsars individual PSR B1259-63 -- binaries general -- stars neutron -- stars early-type

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Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan Pei ren-Lin Li xin-Ran Song Qian-Qian Wan Yu-Ming Wang Han-Zhou Li Wei-Quan Xu Jia-Bao Liao Wei-Bo Wen Jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

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Pan-location mapping and localization for the in-situ science exploration of Zhurong Mars rover

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Science China(Information Sciences) 2022年第7期65卷 170-184页

作者： xingguo zeng Jianjun LIU xin ren Wei YAN Qiang FU xingye GAO Wangli CHEN Wei ZUO Chunlai LI Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences

On May 15, 2021, Tianwen-1 successfully landed in the Utopia Planitia of Mars, and its rover Zhurong began to carry out an in-situ science exploration of the Mars surface. To determine the location,driving direction, and exploration targets of the rover, it is necessary to provide decision support for the in-situ science exploration of the rover and ensure the achievement of the scientific objectives, which pose significant challenges to the ground science team. Based on the classical research on Lunar and planetary localization, navigation and exploration target selection, and the recent study of pan-location cartographic theory, a pan-location mapping method for an in-situ rover exploration is proposed. In addition, a panlocation reference system, mapping data model, and mapping method are designed to realize the localization and visualization of the landing platform, rover, and exploration targets. The mapping method has been successfully applied to the localization, navigation, and science exploration of the target selection involved in the in-situ exploration of the Zhurong rover. The results of this study not only provide vital support to the implementation of the Tianwen-1 mission; they can also be used as instructions for other future in-situ Lunar and planetary exploration missions.

关键词： pan-location mapping planetary exploration geo-visualization Tianwen-1 mission Zhurong rover

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A review on direct synthesis of dimethoxymethane

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Chinese Journal of Chemical Engineering 2022年第10期50卷 43-55页

作者： Jia ren Feng xin Yongsheng Xu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300050China

Polyoxymethylene dimethyl ethers are recognized as the prospective diesel additive to decrease the pollutant emission from the light-duty vehicles,which can be polymerize form the monomer of dimethoxymethane(DMM).The industrial synthesis of DMM is mainly involved two-step process:methanol is oxidized to form the formaldehyde in fixed bed reactor and then reacted with the generated formaldehyde through acetalization in continuous stirred-tank *** to huge energy consumption,this typical synthesis route of DMM needs to be upgraded and more green routes should be *** this review,four state-of-the-art one-step direct synthetic routes,including two upgrading routes(methanol direct oxidation and direct dehydrogenation)and two green routes(methanol diethyl ether direct oxidation and carbon oxides direct hydrogenation),have been summarized and *** with the reaction mechanism and catalytic performance on the different catalysts,the challenges and opportu nities for every synthetic route are *** relationships between catalyst structu re and property in different synthesis strategy are also investigated and then the suggestions of the design of catalyst are given about future research directions that efforts should be made ***,this review can bridge the gap between newly developed catalysts and synthesis technology to realize their commercial applications in the near future.

关键词： Dimethoxymethane(DMM) Direct synthesis Reaction mechanism Catalyst

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